2018 High Power Targetry Workshop
Monday 04 June 2018 - Friday 08 June 2018
Book of Abstracts
Contents
Progress of specimen cutout and damage inspection for used mercury target vessel at J- PARC 0 ...... 1
Blister formation at subcritical doses in Tungsten irradiated by MeV protons 1 ...... 1
Development of High-Radiation-Tolerant Fiber-Optic Sensors for SNS Mercury Target Strain Measurement 3 ...... 1
Commissioning of Gas Injection at SNS 4 ...... 2
Thermal Simulations method for rotated target 5 ...... 2
Criticalities on the maintenance of the Target Assembly for IFMIF-DONES 6 ...... 2
Spallation Neutron Source Target Module Design Improvements 7 ...... 2
Targets for S3: design, fabrication and control under irradiation 8 ...... 3
Progress with manufacturing the first target module for ISIS TS1 Project 9 ...... 3
ISIS Second Target Station 2 Extracted Proton Beam Window Replacement 10 ...... 3
Measurements of Target Strain Mitigation by Gas Injection 11 ...... 4
Microstructural Characterization of Proton-Irradiated Ti-15V-3Cr-3Sn-3Al and SiC-Coated Graphite 12 ...... 4
Design and Thermo-mechanical shock wave computations for beam stoppers at FAIR13 . 4
Spallation Neutron Source Status Update 14 ...... 5
Preliminary Thermomechanical Assessment of DONES Lithium Target System 15 . . . . 5
Status Update of PIE Irradiated Materials from BLIP at PNNL 16 ...... 5
Design and prototyping of the CERN Proton Synchrotron Internal Dump in the Framework of the LHC Injectors Upgrade Project 17 ...... 6
Analysis and Operational Feedback on the Current High Energy Beam Dump in the CERN SPS 18 ...... 6
Design and construction of SPS to LHC transfer lines collimators and LHC collider colli- mators in the framework of the LHC Injectors Upgrade and High Luminosity Projects 19 ...... 7
Design of the Future High Energy Beam Dump for the CERN SPS 20 ...... 7
iii An engineering review of the ISIS facility extracted proton beam windows. 21 ...... 7
Investigation of radiation damage effect on advanced materials under different irradiation conditions 22 ...... 8
Handling, Storage, & Disposal of Neutrino Beam Components at Fermilab 23 ...... 8
Fluidised Tungsten Powder Studies at Rutherford Appleton Laboratory 24 ...... 8
Measuring Residual Strain after Hot Isostatic Pressing of ISIS Target Plates 25 ...... 9
High Power ISOL Target Remote Handling Developments at TRIUMF 26 ...... 9
TRIUMF High-Power Targets - Novel Concepts and Operational Experience 27 ...... 9
Status of large area disk target development for ISOL facility of RAON 28 ...... 10
Challenges in alignment design for the ARIEL electron target station at TRIUMF 29 . . . 10
Perspective of muon production target at J-PARC MLF MUSE 30 ...... 11
High power Beam dump for SARAF phase II 31 ...... 11
Design and development of Super-FRS target area components and remote handling 32 . 12
Beam Dump Facility (BDF) at CERN radiological and environmental assessment 33 . . . . 12
High-power converters for RIB production 34 ...... 12
A first integrated CERN-ISOLDE spallation source operated at 2000℃ with GW instanta- neous beam power for isotope production 35 ...... 13
Characterization of Cavitation-Induced Erosion Damage to Spallation Neutron Source Tar- get Modules Via Laser-Line Scanning 36 ...... 14
A high power density beam dump for ISOL@MYRRHA 37 ...... 14
Remote Replacement of SNS Inner Reflector Plug 38 ...... 15
SNS Core Vessel Water Leak Saga 39 ...... 15
Mark IV Upper Target Design for the Lujan Center 1L Target at LANSCE 40 ...... 16
Improvised electrsopinning set up for mass producing thicker ceramic nanofiber mat for high power targets 41 ...... 16
NOVA Medium energy target ME-1 autopsy, procedure and equipment 42 ...... 16
Thermal diffusivity of proton and spallation neutron irradiated tungsten 43 ...... 17
SNS Hot Cell Design Philosophy 44 ...... 17
Design and Operation of the Mu2e Target Remote Handling System 45 ...... 18
Ion irradiation damage in commercially pure Titanium and Ti-6Al-4V: Characterization of the microstructure and mechanical properties 46 ...... 18
Post-irradiation examinations of SINQ Target-11 47 ...... 19 Optimization of the LBNF Neutrino Beam 48 ...... 19
RaDIATE thermal shock experiments at CERN’s HiRadMat facility 49 ...... 20
Last updates of the R&D activities for the redesign of the CERN’s AD-Target 50 . . . . . 20
Preliminary design study of the integration and remote handling processes for the Beam Dump Facility Target Complex 51 ...... 21
Beam Dump Facility target: design status, beam tests in 2018 and material studies 52 . . . 22
Detailed design, prototyping activities and beam irradiation tests for the new n_TOF neu- tron spallation target 53 ...... 22
Research of Materials in Target Environment at European Spallation Source 54 ...... 23
In-situ studies of phase transition related Pb transport in the SINQ target rods with use of the NEUTRA imaging instrument at PSI 55 ...... 23
Thermo-mechanical analysis of NuMI Horn-1 for NuMI upgrade AIP56 ...... 24
IAEA Activities in Support of the Accelerator Based Simulation and Modelling of Radiation Damage Effects 57 ...... 25
Physics Beyond Colliders at CERN 58 ...... 25
Multi-Physics coupling to model the TMRS Mark IV Middle Tungsten Target Stack 59 . . 25
The LIEBE high-power target: Offline commissioning results. 60 ...... 26
Tungsten Oxidation AeroSol Transport (TOAST) Experiments 61 ...... 26
Diffusion of tritium produced in a graphite and SiC target 62 ...... 27
Exploratory study for the production of Sc beams at the ISOL facility of MYRRHA 63 . . 28
Neutron Source Manufacturing at SNS 64 ...... 28
J-PARC neutrino beam-line and radiation damage studies on Titanium alloys 65 . . . . . 29
Target system maintenance experience in hot cell at J-PARC 66 ...... 29
The ESSnuSB Target Station 67 ...... 29
Techniques and Accomplishments of the Post Irradiation Examination Program at the Spal- lation Neutron Source 68 ...... 30
The Influence of High Energy Proton Irradiation on Fine-Grained Isotropic Graphite Grades: A Summary of Recent RaDIATE Results 69 ...... 30
Compact Sealed lithium target for accelerator-driven BNCT system 70 ...... 31
Targets for the SPES project and its applications: material selection and release simulations 71 ...... 32
HiRadMat: A Unique Facility Testing Materials with High Power Pulsed Beam 72 . . . . 32
Design of high temperature ISOL targets 73 ...... 33 Energy deposition in Candidate Materials for the Whole-Beam Dumps for the Advanced Photon Source Upgrade 74 ...... 33
Design, study and tests of the Beam Dump for the SPES cyclotron commissioning 75 . . . 34
Design Optimization of the Mu2e Production Target 76 ...... 34
Recent developments of Hot Isostatic Pressing diffusion bonding technologies to enhance cooling efficiency and reliability of proton beam targets and dumps atCERN77 . . . 35
High Power Liquid Lead-bismuth Targetry for Intense Fast Neutron Sources Using a Super- conducting Electron Linac 78 ...... 35
High Power Capability of the Primary Beam Dump Drum for FRIB – Simulation and Ex- perimental Study 79 ...... 36
FRIB Radiation Studies: Damage, Component Lifetimes, Hands-on Accessibility 80 . . . . 36
Conceptual design of the granular 81 ...... 37
Operation of and Upgrade Plans for the LANSCE Pulsed Neutron Sources 82 ...... 37
Radiation Protection at CERN - learn from the past and prepare for the future 86 . . . . . 38
Isotope Harvesting at FRIB 87 ...... 38
Welcome Talk 91 ...... 39
High Power Targetry at FRIB 92 ...... 39
Targets for the SPES project and its applications: material selection and release simulations 93 ...... 39 2018 High Power Targetry Workshop / Book of Abstracts
Session 3-Post Irradiation Examination / 0
Progress of specimen cutout and damage inspection for used mer- cury target vessel at J-PARC
Author: Takashi Naoe1
Co-authors: Hidetaka Kinoshita 1; Hiroshi Takada 1; Hiroyuki Kogawa 1; Katsuhiro Haga 1; Takashi Wakui 1
1 Japan Atomic Energy Agency
Corresponding Author: [email protected]
J-PARC mercury target vessel was cut in 2017. Prior to the target cutting, cutting tests were con- ducted to optimize cutting conditions based on the experienced difficulties in previous cutting.Im- provement in specimen cutout by remote handling and results of cavitation damage observation will be reported.
Session 2-Radiation Damage in Target Material and Related Simulations / 1
Blister formation at subcritical doses in Tungsten irradiated by MeV protons
Author: Inbal Gavish Segev1
Co-author: Ido Silverman 2
1 Soreq NRC 2 Soreq
Corresponding Author: [email protected]
Tungsten response to MeV protons irradiation has been studied experimentally, in particular with re- spect to bubbles and blister formation. Large, well-developed blisters are observed at 10ˆ17protons/cm2, below the reported critical dose from kev irradiations.
Session 7-Operation of Targets and Beam Dumps / 3
Development of High-Radiation-Tolerant Fiber-Optic Sensors for SNS Mercury Target Strain Measurement
Author: Yun Liu1
Co-authors: Bernard Riemer 1; Cary Long 1; Drew Winder 1; Mark Wendel 1; Willem Blokland 2
1 Oak Ridge National Laboratory 2 ORNL
Corresponding Author: [email protected]
A low-coherence interferometer-based fiber-optic sensor has been developed to measure thedy- namic strains in the SNS mercury target. Measurement bandwidth and radiation tolerance are an order of magnitude higher than commercial products. Measurement performance in the recent SNS target is described.
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Session 7-Operation of Targets and Beam Dumps / 4
Commissioning of Gas Injection at SNS
Author: Charlotte Barbier1 Co-authors: Bernard Riemer 2; Mark Wendel 1
1 ORNL 2 Oak Ridge National Laboratory
Corresponding Author: [email protected]
Details of the commissioning plan phases and the goals of each steps, observations and lessons learned during the commissioning will be presented. Finally, the path to include gas injection into routing operation and to potentially inject more gas will be also presented.
Poster Session and Reception / 5
Thermal Simulations method for rotated target
Author: Matthieu Michel1
1 CNRS-GANIL
Corresponding Author: [email protected]
Rotating target FEA methods
6 Criticalities on the maintenance of the Target Assembly for IFMIF- DONES
Author: Gioacchino Miccichè1 Co-authors: Angel Ibarra 2; Davide Bernardi 1; Fabrizio Frascati 1; Luciano Lorenzelli 1
1 ENEA 2 CIEMAT
Corresponding Author: [email protected]
The maintenance of lithium target of the DEMO Oriented NEutrons Source (DONES) isarather complex activity requiring the employment of sophisticated remote handling technologies. Critical- ities on the maintenance tasks to be performed and solutions adopted are discussed in the presenta- tion/poster.
Session 4-Target Design, Analysis, Validation of Concepts / 7
Spallation Neutron Source Target Module Design Improvements
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Author: Drew Winder1
1 Oak Ridge National Laboratory
Corresponding Author: [email protected]
The Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory produces neutrons for scientific research by striking mercury with a short-pulse (0.7 μs) proton beam with a 60Hzrate. The mercury material flows through a stainless-steel target vessel, which is subjected to cyclicload- ings and cavitation erosion. The target vessels are consumable components, but their reliability is critical to overall SNS reliability. The SNS has operated 18 target vessels. Of those, 7 have developed mercury leaks during operation. A mercury leak results in an unexpected target end-of-life which interrupts the scheduled user program. After two targets developed leaks in 2014, a significant effort was undertaken to improve understand- ing of the targets and to implement new design features. These efforts are bearing fruit, as improved target designs have now been operating and more information is available for further improvements. The current state of SNS target vessel design will be presented along with recent performance data. Future designs for targets will be presented, including targets intended for use at 1.4 MW which are in various stages of fabrication and design, as well as conceptual designs for a target intended to operate at 2.0 MW. The overall multi-year operational plan for SNS target fabrication and operation will also be presented.
Session 7-Operation of Targets and Beam Dumps / 8
Targets for S3: design, fabrication and control under irradiation
Author: Christelle STODEL1 Co-author: Thierry Lefrou 2
1 Grand Accélérateur National d’Ions Lourds 2 GANIL
Corresponding Author: [email protected]
A major experimental concern of thin targets is their behavior under highly intense heavy ion beams. We propose to report on the experimental set-up under consideration (electron gun and infrared camera) and to discuss on the present results.
Session 6-Construction, Fabrication, Inspection, Quality Assurance / 9
Progress with manufacturing the first target module for ISIS TS1 Project
Author: Leslie Jones1
1 ISIS Synchrotron
Corresponding Author: [email protected]
ISIS has its own Target Manufacturing Facility for making the W/Ta target plates. I will share the experience and challenges of making the first new design target plates and other main components of the TS1 Project Target. There have been some lessons learned along the way.
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Session 5-Target Facility Challenges / 10
ISIS Second Target Station 2 Extracted Proton Beam Window Re- placement
Author: DAN COATES1
1 STFC\UKRI\RAL\ISIS
Corresponding Author: [email protected]
ISIS uses proton beam windows for both its two target stations as means of separation between the target void vessel environment and accelerator vacuum. The window with an expected life time of 20 years failed prematurely on the 19th of October 2017 after only 9 years of operation.
Session 1-R&D to Support Concepts / 11
Measurements of Target Strain Mitigation by Gas Injection
Author: Willem Blokland1 Co-authors: Drew Winder 2; Yun Liu 2
1 ORNL 2 Oak Ridge National Laboratory
Corresponding Author: [email protected]
Strain measurements were taken at multiple locations on the SNS stainless-steel. mercury filled target with and without gas injection at beam pulse energies up to 23.3 kJ. The strain was also measured as a function of the gas injection rate.
Poster Session and Reception / 12
Microstructural Characterization of Proton-Irradiated Ti-15V-3Cr- 3Sn-3Al and SiC-Coated Graphite
Author: David Senor1 Co-authors: Alan Schemer-Kohrn 1; Andrew Casella 2; Dan Edwards 1; Dan Schreiber 1; Eiichi Wakai 3; Karen Kruska 1; Ramprashad Prabhakaran 1; Shunsuke Makimura 4; Taku Ishida 4
1 Pacific Northwest National Laboratory 2 PNNL 3 JAEA 4 J-PARC/KEK
Corresponding Author: [email protected]
The presentation will address post-irradiation microstructural characterization of a Ti-15V-3Cr-3Sn- 3Al OTR foil irradiated by 30 GeV protons at the J-PARC neutrino beamline to 0.4 dpa, and SiC-coated graphite samples irradiated by 180 MeV protons at the BLIP facility to 0.05 dpa.
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13 Design and Thermo-mechanical shock wave computations for beam stoppers at FAIR
Author: Amit Kumar1
Co-authors: Abhiijit Mahapatra 1; Avik Chatterjee 1; Helmut Weick 2
1 CSIR-Central Mechanical Engineering Research Institute 2 GSI Helmholtzzentrum
Corresponding Author: [email protected]
The design of beam stoppers for the Super-FRS at FAIR will be presented. The transient thermo- mechanical shock wave computations for pulse form deposition (fast extraction) as well as thermal performance, design optimization for pulsed and quasi DC deposition (slow extraction) shall be pre- sented.
Session 7-Operation of Targets and Beam Dumps / 14
Spallation Neutron Source Status Update
Author: Bernard Riemer1
1 Oak Ridge National Laboratory
Corresponding Author: [email protected]
This presentation will highlight Spallation Neutron Source (SNS) achievements and difficulties since the High Power Targetry Workshop in April of 2016.
15 Preliminary Thermomechanical Assessment of DONES Lithium Target System
Author: Davide Bernardi1
Co-authors: Francesco Saverio Nitti 1; Gioacchino Miccichè 1; Manuela Frisoni 1; Pietro Alessandro Di Maio 2; Pietro Arena 2
1 ENEA 2 University of Palermo
Corresponding Author: [email protected]
A preliminary thermomechanical analysis of the target system of DEMO-Oriented early NEutron Source (DONES) under steady state conditions was performed within the EUROfusion workpackage WPENS. Results obtained are presented here showing that the structural integrity of the system is guaranteed.
Session 3-Post Irradiation Examination / 16
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Status Update of PIE Irradiated Materials from BLIP at PNNL
Author: Andy Casella1 Co-authors: Bob Orton 1; David Senor 1; Shawn Riechers 1; TS Byun 1
1 PNNL
Corresponding Author: [email protected]
PNNL has received three irradiated capsules; fabricated and tested a capsule opener; designed a tensile test fixture; and commissioned a new AFM. Opener installation; capsule opening andsam- ple sorting; tensile and hardness tests are imminent with results anticipated in time for this meet- ing.
Session 5-Target Facility Challenges / 17
Design and prototyping of the CERN Proton Synchrotron Inter- nal Dump in the Framework of the LHC Injectors Upgrade Project
Authors: Francois-Xavier Nuiry1; Giulia Romagnoli1; Jaakko Esala1; Jose Briz Monago1 Co-authors: Alessandro Masi 1; Alexander Huschauer 1; Didier Steyaert 1; Edouard Grenier-Boley 1; Klaus Hanke 1; Marco Calviani 1; Mark Butcher 1; Vasilis Vlachoudis 1; Yannick Coutron 1
1 CERN
Corresponding Author: francois-xavier.nuiry@cern.ch
Proton Beam Dump, Copper alloy, Isostatic Graphite, Radhard Mechanism, Hot Isostatic Pressing, water cooling
Session 7-Operation of Targets and Beam Dumps / 18
Analysis and Operational Feedback on the Current High Energy Beam Dump in the CERN SPS
Author: Antonio Perillo-Marcone1 Co-authors: Didier Steyaert 1; Jerome Humbert 1; Jose Antonio Briz Monago 1; Marco Calviani 1; Stefano Sgobba 1
1 CERN
Corresponding Author: [email protected]
The CERN Super Proton Synchrotron (SPS) high-energy internal dump (TIDVG) is used tointercept beam dumps from 102.2 to 450 GeV. The previous device featured an absorbing core composed of different materials (graphite, aluminium, copper and a tungsten alloy) surrounded by a water cooled copper jacket. An inspection in 2013 revealed significant beam induced damage to the aluminium absorbing block, resulting in operational limitations to minimise the risk of reproducing this phe- nomenon. Additionally, in 2016 a vacuum leak was detected in the dump assembly, which imposed further restrictions to operations, i.e. a reduction of the beam intensity that could be dumped. In the winter stop of 2016-2017, a new version of the TIDVG (featuring several design modifications) was installed. With the proposed design, an average beam power of 60 kW can be dumped continuously (approximately 90% of the beam power is actually absorbed by the dump-shielding assembly).
Page 6 2018 High Power Targetry Workshop / Book of Abstracts
This paper analyses the design of the new device and its performance observed during the commis- sioning period and subsequent operation in 2017. The temperature measurements recorded during this time were used to benchmark numerical models that allow predicting the behaviour of the dump under different conditions. After several iterations, a good agreement between simulations andreal measurements was obtained; resulting in numerical models that can produce reliable results for this and other devices with similar design.
19 Design and construction of SPS to LHC transfer lines collimators and LHC collider collimators in the framework of the LHC Injec- tors Upgrade and High Luminosity Projects
Authors: Francois-Xavier Nuiry1; Inigo Lamas Garcia1; Maxime Bergeret1; Ricardo Illian Fiastre1 Co-authors: Anton Lechner 1; Luca Gentini 1; Marco Calviani 1; Matthias Frankl 1; Oliver Aberle 1; Stefano Pianese 1
1 CERN
Corresponding Author: [email protected]
Proton beam collimators, 3D and 2D Carbon/carbon, Isostatic Graphite, Molybdenum-graphite
Poster Session and Reception / 20
Design of the Future High Energy Beam Dump for the CERN SPS
Author: Antonio Perillo-Marcone1 Co-authors: Damien Grenier 1; Didier Steyaert 1; Jerome Humbert 1; Jose Antonio Briz Monago 1; Marco Calviani 1; Philipp Heckmann 1; Stefano Pianese 1; Stefano Sgobba 1
1 CERN
Corresponding Author: [email protected]
The future CERN Super Proton Synchrotron (SPS) internal dump (Target Internal Dump Vertical Graphite, known as TIDVG#5), to be installed during CERN’s Long Shutdown 2 (LS2, 2019-2020), will be required to intercept beam dumps from 14 to 450 GeV, with increased intensity and repeti- tion rates with respect to its predecessor (TIDVG#4). The new dump will be installed at a different location in the accelerator (LSS5) as this areaprovides more space and hence increased flexibility for a new design (including a massive shielding) capable of coping with the upgraded beams expected after LS2. The average beam power to be managed by the dump will be as high as 236 kW (hence, almostfour times higher than presently). This increased power produces new challenges in terms of design inor- der to fulfil the highly demanding specification, which is based on guaranteeing a good performance of the machine with little or no limitations imposed by the dump itself (to note that approximately 90% of the beam power is actually absorbed by the dump-shielding assembly). This paper presents the proposed design, including material selection, manufacturing techniques and thermo-mechanical simulations under different operational scenarios expected during the lifetime of the device.
Session 5-Target Facility Challenges / 21
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An engineering review of the ISIS facility extracted proton beam windows.
Author: Daniel Blanco Lopez1
1 UKRI/STFC, RAL, ISIS
Corresponding Author: [email protected]
The extracted proton beam (EPB) windows separating the proton beam transfer lines fromeach neutron target stations are key components in the ISIS neutron spallation source. This work focuses on the different designs employed and their challenges on operation and replacement.
Session 2-Radiation Damage in Target Material and Related Simulations / 22
Investigation of radiation damage effect on advanced materials under different irradiation conditions
Author: CARLOTTA ACCETTURA1 Co-authors: Alessandro Bertarelli 2; Anton Lechner 2; Federico Carra 2; Marilena Tomut 3
1 Politecnico di Milano and CERN 2 CERN 3 GSI
Corresponding Author: [email protected]
This talk will summarize the irradiation tests performed on novel collimator materials. In particular, it will focus on the radiation induced microstructural changes that affect the macroscopic properties such as electrical and thermal conductivity.
Session 5-Target Facility Challenges / 23
Handling, Storage, & Disposal of Neutrino Beam Components at Fermilab
Author: Cory Crowley1
1 Fermi National Accelerator Lab
Corresponding Author: [email protected]
Continued operation of Fermilab target facilities yields a waste stream of radioactive components at the end of their usable life. These components must be removed, stored, and disposed ofinan environmentally sound and legally compliant manner. Methods for achieving this at Fermilab are discussed.
Poster Session and Reception / 24
Fluidised Tungsten Powder Studies at Rutherford Appleton Lab- oratory
Page 8 2018 High Power Targetry Workshop / Book of Abstracts
Author: Dan Wilcox1
1 RAL
Corresponding Author: [email protected]
A test rig for fluidised tungsten powder was built at RAL. The rig demonstrates all the powderhan- dling processes necessary for operating a future facility using this promising new target technol- ogy.
Session 6-Construction, Fabrication, Inspection, Quality Assurance / 25
Measuring Residual Strain after Hot Isostatic Pressing of ISIS Tar- get Plates
Author: Dan Wilcox1
1 RAL
Corresponding Author: [email protected]
A novel method was used to measure residual stress in tantalum-clad tungsten after manufacture via Hot Isostatic Pressing. A significant tensile tress was measured in the cladding, as predicted by FEA simulations. This will be an important consideration in the design of future spallation tar- gets.
Session 5-Target Facility Challenges / 26
High Power ISOL Target Remote Handling Developments at TRI- UMF
Author: Grant Minor1
Co-author: Alexander Gottberg 1
1 TRIUMF
Corresponding Author: gminor@triumf.ca
TRIUMF maintains a high power ISOL target facility called ISAC (Isotope Separator and Accelerator), which generates about 10 waste targets per year with dose rates up to 1 Sv/h at 1 m. TRIUMF has re- mote handling infrastructure in place for servicing the ISAC target modules, including a hot cell and remote bridge crane. Upgrades underway include a second hot cell and a crane rotation redundancy system. These improvements will permit routine target exchanges and extended module repairsin parallel, increasing the reliability of the facility. TRIUMF is also developing a new ISOL target facil- ity called ARIEL (Advanced Rare IsotopE Laboratory). TRIUMF will make use of modern technology and apply lessons learned from ISAC to the ARIEL remote handling facility design. Recent ARIEL developments include a maintenance and waste-processing hot cell, as well as a crane-based remote handling system for a novel target module, which is a hybrid of the CERN ISOLDE and TRIUMF ISAC systems.
27
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TRIUMF High-Power Targets - Novel Concepts and Operational Experience
Author: Alexander Gottberg1
1 TRIUMF
Corresponding Author: [email protected]
The ISOL (Isotope Separation OnLine) technique delivers exotic radioisotopes for a wide rangeof experiments. TRIUMF’s current flagship project - Advanced Rare IsotopE Laboratory (ARIEL) - will not only dra- matically increase the availability of pure radioisotope but also enable the delivery of three radioiso- tope beams simultaneously - a worldwide unprecedented technology - enhancing the scientific out- put of the laboratory. In addition to three target stations that will be served by 50 kW, 500 MeV pro- tons, a second independent driver will supply a fourth target station. Here, high-power electrons (up to 500 kW) will be converted into gamma rays inducing photonuclear reactions in the target. Since the intrinsic properties of 35-50 MeV electrons are fundamentally different than of MeV neutrons or 0.1 to 2 GeV protons, commonly used for ISOL, the design of the ARIEL electron target stations and its adjacent systems will differ radically from any exiting ISOL target design.
Poster Session and Reception / 28
Status of large area disk target development for ISOL facility of RAON
Author: MIJOUNG JOUNG1 Co-authors: B.H. Kang 1; J.W. Jeong 1; Jang Youl Kim 2; S.G. Hong 1; S.H. Na 3; W. Hwang 1
1 IBS 2 Institute for basic science 3 KAERI
Corresponding Author: [email protected]
The compound of uranium carbide (UCx-C) target will be used for ISOL facility of RAON. However, Lanthanum de-carbide (LaC2) was used to carry out advanced research for optimal condition of fabrication instead of UCx-C because the uranium is radio-active material and lanthanum carbide has a similar properties to uranium carbide. A compound disk of lanthanum carbide (LaC2-C) of 50 mm in diameter, which lanthanum de-carbide with Multi-Wall Carbon Nano-Tube (MWCNT) was fabricated and tested. The long-term high temperature test was carried out at 1600℃, 1800℃ and 2000℃. Test duration was 20 hrs and 48 hrs respectively. The disks were analyzed in terms of weight, diameter, micro-structure, composition and density. Research and development for UCx-C based on the result of LaC2-C test is carrying out, the status will be introduced with the TIS (Target and Ion Source) system in this presentation.
29 Challenges in alignment design for the ARIEL electron target sta- tion at TRIUMF
Author: Kevin Chen1 Co-author: ARIEL Development Team 1
1 TRIUMF
Page 10 2018 High Power Targetry Workshop / Book of Abstracts
Corresponding Author: [email protected]
ARIEL will add two new independent production targets and driver beamlines (electron and proton) to increase RIB productions at TRIUMF. Presently, the ARIEL building is complete, and an e-Linac (up to 10 mA) with 30 MeV capability (upgradeable to 50MeV) has been installed as the driver for the electron target station. The ARIEL Electron Station East (AETE) is being developed and tested and faces some unique challenges to meet the alignment requirements of repeatable alignment be- tween the ion source and the extraction electrode to within a positional tolerance of +/-0.5mm and a rotational tolerance of <5mRad. This alignment is affected by a variety of factors, including thermal expansion due to heat loads from gamma radiation, as well as the design of the remote connection system between the ion source and extraction electrode. The alignment and remote coupling design will be presented.
Session 7-Operation of Targets and Beam Dumps / 30
Perspective of muon production target at J-PARC MLF MUSE
Author: Shunsuke Makimura1
1 J-PARC/KEK
Corresponding Author: [email protected]
A pulsed muon beam with unprecedented intensity will be generated by a 3-GeV 333-microA proton beam on a muon target made of 20-mm thick isotropic graphite at J-PARC MLF MUSE (Muon Science Establishment). The muon rotating target was newly installed in September of 2014, anditwas confirmed that the rotating target could stand up to 500-kW proton beam operation. Subsequently, continuous and stable operation has been successfully performed for three years and four months. Further upgrade of beam power up to 1 MW is expected. We must prepare for the high power operation. Recently, new developments of muon target for further higher power operation are in progress. The investigation or the developments of SiC coated graphite, SiC composite material, and ductile tungsten as a new target material is in progress. The perspective of the muon production target at J-PARC MLF MUSE will be introduced inthis presentation.
Session 4-Target Design, Analysis, Validation of Concepts / 31
High power Beam dump for SARAF phase II
Authors: Arenshtam Alex1; Barami Eli1; Bukai Moshe1; Eliyahu Ilan1; Gavish Inbal1; Kreisel Arik1; Moreno Daniel1; Rodnizki Jacob1; Vaintraub Sergey1
1 Soreq Nuclear Research Center
Corresponding Author: [email protected]
Soreq Applied Research Accelerator Facility (SARAF) is based on a proton/deuteron RF supercon- ducting linear accelerator. Phase I, has already been completed and allows acceleration of 1 mA CW, 4 MeV proton beams and low duty cycle acceleration of 5 MeV deuterons. Phase II of the project is under way and includes the development of the accelerator to its final specifications: energy of 40MeV proton/deuteron, and a current of up to 5mA. A beam dump will be required at the commis- sioning stage and for daily operations. The beam dump must be designed to stop a beam witha maximum power of 200 kW. To avoid radiation damage and improve heat transfer, a design concept of liquid metal target is suggested, based on our vast experience with the Lithium target at SARAF. The suggested liquid is a Ga-In-Sn metal alloy (Gallinstan) with a melting point of 10oC, designedto dissipate beam powers of 200 kW. The setup is based on a high-velocity windowless Gallium-Indium jet
Page 11 2018 High Power Targetry Workshop / Book of Abstracts
Session 5-Target Facility Challenges / 32
Design and development of Super-FRS target area components and remote handling
Author: Faraz Amjad1
Co-authors: Abhijit Mahapatra 2; Amit Kumar 2; Avik Chatterjee 3; Catherine Rigollet 4; Christos Karagiannis 1; Ekaterina Kozlova 1; Helmut Weick 5; Henk Smit 4; Michel Lindemulde 4; Nasser Kalantar 4
1 GSI Helmholtzzentrum für Schwerionenforschung GmbH 2 CSIR-Central Mechanical Engineering Research Institute 3 CSIR, Central Mechanical Engineering Research Institute 4 KVI-CART, University of Groningen 5 GSI Helmholtzzentrum
Corresponding Author: [email protected]
With the Super-conducting Fragment Separator (Super-FRS) at FAIR, rare isotopes of all elements up to uranium will be produced via fission or fragmentation in flight. The primary beam iscon- verted in a graphite wheel target and separated in the following magnetic separator. The separator is surrounded by many meters of shielding with gaps for the beam line vacuum chambers, which are connected by up to 1.2 m wide pillow seals. Inside the chambers, various devices (target, beam diagnostic detectors, a collimator, and beam dumps) are mounted on shielding plugs. The target and the beam dump suffer from radiation damage due to the heavy-ion beam and regular mainte- nance will be required. To conduct the remote maintenance, the plugs will be transported from the beamline using a 60 ton (5.8 m high) shielding flask to a hot cell. The hot cell will be equipped with master-slave manipulators and a power manipulator to replace the consumable parts and carry out the remote maintenance.
Session 5-Target Facility Challenges / 33
Beam Dump Facility (BDF) at CERN radiological and environmen- tal assessment
Authors: Claudia Strabel1; Heinz Vincke1; Mirkoantonio Casolino1; Stefan Roesler1
Co-authors: Edmundo Lopez Sola 1; Jean-Louis Grenard 1; Joao Pedro Canhoto Espadal 1; Josep Busom 1; Keith Kershaw 1; Marco Calviani 1; Mike Lamont 1; Pietro Avigni 1; Richard Jacobsson 1
1 CERN
Corresponding Author: [email protected]
The Beam Dump Facility (BDF), currently in its design phase, is a proposed fixed target facility at CERN, dedicated to the Search for Hidden Particles (SHiP). In order to isolate possibly existing hidden particles a high-density and high-Z target is used to fully absorb the hadronic and electro- magnetic particle cascade caused by the impact of a high-intensity 400 GeV/c proton beam. Due to such experimental conditions, high levels of material activation is expected. The evaluation of radiation protection hazards is a challenging aspect for the design of this facility. In particular, high prompt and residual dose rates call for considerable shielding and remote-handling interventions in the target area. Moreover, the risk of an environmental impact stemming from air, water and soil ac- tivation heavily influences the design. This paper discusses the results of a radiological study, using FLUKA MC simulations and the ActiWiz code, to assess the above-mentioned radiation protection aspects.
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Session 4-Target Design, Analysis, Validation of Concepts / 34
High-power converters for RIB production
Author: Luca Egoriti1
Co-authors: ARIEL DEVELOMPENT TEAM 1; collaboration p2n 2
1 TRIUMF 2 TRIUMF, ISOLDE, SCK-CEN
Corresponding Author: [email protected]
TRIUMF is developing two target assemblies for radioisotope production based on the conversion of primary charged particle beams into neutral particle fluxes, which consequently induce fission ina uranium carbide (UCx) target. One is a proton-to-neutron converter made out of a 2 cm thick tungsten core clamped by copper brackets to dissipate up to 7.5 kW deposited by a 500 MeV, 100 uA proton beam. The high-energy isotropic neutrons will then induce cold fission in an annular UCx target material upstream ofthe converter. The other is an electron-to-gamma converter made out of a thin tantalum layer deposited onan aluminum backing. A 35 MeV electron beam of up to 100 kW will impinge on the tantalum surface and produce a gamma-ray flux, principally in the forward direction of a downstream UCx target. This contribution focuses on some of the design challenges resulting from the extreme conditions in terms of power density, temperature and radiation.
Session 1-R&D to Support Concepts / 35
A first integrated CERN-ISOLDE spallation source operated at 2000°C with GW instantaneous beam power for isotope production
Author: J.P. Ramos1
Co-authors: A. Gottberg 2; D. Houngbo 3; L. Egoriti 2; Lucia Popescu 3; M. Ballan 4; M. Dierckx 3; R.S. Augusto 1; Sebastian Rothe 1; Stefano Marzari 1; Thierry Stora 1
1 CERN 2 TRIUMF 3 SCK-CEN 4 INFN-LNL
Corresponding Author: [email protected]
Neutron-rich fission fragments are readily available at CERN-ISOLDE. However, if produced bydi- rect irradiation (1.4GeV - 2μA pulsed protons) of a uranium carbide (UCx) target, the desired isotopes come with very high isobaric neutron-deficient fission fragments. Instead, irradiating a W spalla- tion source, the neutrons produced irradiate the target producing high purity neutron-rich fission fragments. However, scattered protons from the W hit the target producing impurities, and asmall solid angle intercepting the target causes a reduced beam intensity. A converter design optimization has been proposed before and a simplified version has been tested[1], where in both current and tested prototype designs, the converter is positioned just below the target. A solution where the converter is positioned inside of the target is, for the first time, being studied in a collaboration with SCK-CEN and TRIUMF. This solution presents the advantage of using the full solid angle of the emitted neutrons, and have the highest possible neutron flux by being in close prox- imity with the UCx target. However, challenges arise from the coupling of the converter and heating of the target, nominally operated at 2000℃ or higher. A much larger target oven/heat screens are as well needed as well as chemical stability of the full assembly at 2000℃. Furthermore, from the
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pulsed proton beam, up to 700W (2.8kW - 1.2GW instantaneous power) are deposited in the target, while submitting the W to severe thermo-mechanical stresses. Since the W converter sits insideof the target oven, it acts as an internal heat source which needs to be compensated to avoid target degradation and promote isotope release. This concept will be designed to accommodate alsothe ISOLDE upgrade to 2GeV - 6μA. [1] A. Gottberg, et al., NIMB 336 (2014) 143–148.
36 Characterization of Cavitation-Induced Erosion Damage to Spal- lation Neutron Source Target Modules Via Laser-Line Scanning
Author: David McClintock1
1 Oak Ridge National Laboratory
Corresponding Author: [email protected]
During operation, the interior mercury-facing surfaces of targets at the Spallation Neutron Source (SNS) are damaged via cavitation-induced erosion. While leaks have occurred in SNS targets during the first nine years of operation, it wasn’t until September 2015 that SNS Target 12 leakeddueto cavitation-induced erosion. After the Target 12 leak occurred efforts were made to characterize the extend of erosion damage to specimens removed from SNS targets. A noncontact measurement technique called laser-line scanning was investigated and eventually implemented to scan samples removed from beam entrance region of SNS target modules. The scans provided a high-density point cloud of the specimen surfaces with a resolution of ±25 microns. The high resolution topography data produced by the laser-line scanner has facilitated the calculation of metrics to characterize the extent and severity of erosion to the target vessel surfaces. These metrics have provided a better understanding of the relationship(s) between operating power, total absorbed energy, and erosion damage. In addition to characterization of erosion damage, the laser-line scanning technique can also be used for many different reverse engineering and topographical characterization needs. The utilization of the laser-line scanning technique for SNS target samples, associated data analysis, and results will be presented during this talk.
Session 4-Target Design, Analysis, Validation of Concepts / 37
A high power density beam dump for ISOL@MYRRHA
Author: Donald HOUNGBO1
Co-authors: Lucia Popescu 1; Marc Dierckx 1
1 SCK-CEN
Corresponding Author: [email protected]
Similar to other next generation RIB facilities, ISOL@MYRRHA is based on a high intensity proton beam in order to meet users’ requirements of a significant increase of isotope yields. In the first phase of the MYRRHA project, the combination of the beam intensity (0.5 mA) and energy (100 MeV), delivered by the MYRRHA linac, together with a beam spot of a few mm in radius, results in a beam dump facing heat deposition density values significantly above to those of high energy beam facilities currently in operation. In order to reduce heat deposition densities, conical- or wedge-shape beam dump concepts have been proposed and are mainly suited for beam spots larger than those foreseen at ISOL@MYRRHA.
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In addition, a beam expansion is not readily feasible for a beam dump placed after an ISOL target irradiated with a 100 MeV proton beam. Moreover, the beam dump would have to fit two dissimilar enveloping cases: i) a full focused beam, ii) a partially defocused beam due to interaction with the target. An innovative multiple-foil concept of beam dump design is thus proposed here. A major aspect of this concept is that it relies on radiative cooling of the dump material. A tight contact between the dump material and the cooling liquid is thus avoided so that when needed the low activity cooling circuit can be easily separated from the dump material for maintenance or end-of-life disposal. The details of the material selection will be presented, through a material comparison covering aspects like radiation hazards, material activation, heat deposition, heat removal ability and the radiation- induced production of low-solubility gases like tritium. Finally, the design optimization results obtained through investigation of gradually improved concepts will be presented, along with the current design of the dump.
38 Remote Replacement of SNS Inner Reflector Plug
Author: Michael Dayton1
1 ORNL-SNS
Corresponding Author: [email protected]
ORNL’s Spallation Neutron Source (SNS) recently completed the first remote replacement of the In- ner Reflector Plug (IRP). This IRP was initially installed during construction and operated formore than 40 GW-hrs. Replacement of the large and highly-activated IRP presents significant challenges that are compounded by the critical nature of this component to SNS operation. Details of the IRP configuration and installation will be discussed along with the planning and preparations forthere- placement operation. An overview of the remote handling tooling, shielded casks and the details of the remote operations will be presented. Neutronics analyses performed to support the replacement operation predicted dose rates in excess of those experienced during previous remote operations leading to significant ALARA planning. An overview of this planning, the resulting precautions im- plemented during the operation and the actual radiological conditions encountered will be discussed. Installation and alignment operations associated with the new IRP will be discussed. Challenges, un- expected events and lessons learned will be covered.
Session 5-Target Facility Challenges / 39
SNS Core Vessel Water Leak Saga
Author: Michael Dayton1
1 ORNL-SNS
Corresponding Author: [email protected]
ORNL’s Spallation Neutron Source (SNS) operates its Core Vessel with a helium atmosphere in part to mitigate potential corrosion of critical components. Components within the Core Vessel are cooled by three independent water cooling loops. For the first time since SNS operations began in 2006, the presence of liquid water was detected in a Core Vessel drain in September 2016. While the design of the Core Vessel system provides a means to remove leaking water, the presence of liquid water represents an operational risk making it imperative to mitigate or eliminate the source of the leak. Following this leak indication in 2016, SNS engineering and operations personnel embarked on a journey to understand and solve this problem. Discovery of the initial leak will be discussed along with efforts to quantify the leak rate and origin. A subsequent maintenance outage enabled removal of the Core Vessel lid for further investigation revealing a source of the leak. An innovative
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solution to this leak was developed to remove the water the Core Vessel and return it directly to the cooling loop. Details of this solution will be discussed. Despite these efforts, leaks have persisted resulting in several operational impacts. Recent replacement of the Inner Reflector Plug provided the opportunity to perform a visual inspection of the Core Vessel. The results and findings of this inspection will be discussed along with potential actions.
Session 4-Target Design, Analysis, Validation of Concepts / 40
Mark IV Upper Target Design for the Lujan Center 1L Target at LANSCE
Author: Keith Woloshun1 Co-authors: Angela Naranjo 1; Eric Olivas 1
1 LANL
Corresponding Author: [email protected]
The Los Alamos Neutron Scattering Center target at the Lujan Center is now operating its 3rdtarget. This is comprised of 2 targets, the first “upper” target is a stack of Ta-clad W disks of varyingthick- ness, the 2nd is a Ta-clad W cylinder located below. The 800 MeV proton beam strikes the upper target on the flat faces of the disks. To accommodate changing experimental needs, anewupper target has been designed that is comprised of one of the Mark III upper target disks but turned on edge, so that the proton beam strikes the curved edge. In addition, 2 cm of water moderator are incorporated on one face of this target. This target orientation, configuration and resulting beam heating profile (approximately 14 kWth on the edge of a 1.8 cm thick disk) requires a novel target housing design that ensures adequate cooling. This paper will detail the target design and supporting analysis.
Poster Session and Reception / 41
Improvised electrsopinning set up for mass producing thicker ce- ramic nanofiber mat for high power targets
Author: Sujit Bidhar1 Co-author: Kris Anderson 2
1 FNAL 2 Fermilab
Corresponding Author: [email protected]
A compact nanofiber production unit with capability to produce variety of ceramic nanofibers using very low power output low voltage DC input inexpensive DC-DC voltage converter with dual polar- ity high voltage DC supply has been developed. The device is much smaller light weight and simpli- fier than conventional electrospinning unit. The device is much safer to use as it limits theoutput power to only few watts and can be operated out of a 9V battery as well as 12V DC adapter. System is a versatile unit employing syringe needled spinneret for prototype nanofiber and a customized 3d printed delivery system with spiked helical spinneret for mass production. It also produces thicker nanofiber mat using corona ionizer.
Session 3-Post Irradiation Examination / 42
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NOVA Medium energy target ME-1 autopsy, procedure and equip- ment
Author: Vladimir Sidorov1
1 Fermilab
Corresponding Author: [email protected]
The purpose of the Medium energy target autopsy is the observation of the graphite fins.The graphite fins are major component of the target that are taking beam during operation. Thetar- get ME-1 is cooled down more than one year, but is still high radioactive. The target is delivered to the C-0 Remote Handling facility and placed on the stands inside the work cell by crane and aligned with the fixture. The work cell is equipped with manipulators, lead glass window and video cameras. The fixture has the high torque power tool that is used for a removing the target downstream end flange. The cart with video cameras is inserted into the opened target canister by manipulator and traveling there observing target fins. The video is translated to the video center located outsideof the work cell.
Session 3-Post Irradiation Examination / 43
Thermal diffusivity of proton and spallation neutron irradiated tungsten
Author: Jemila Habainy1 Co-authors: Srinivasan Iyengar 2; Yong Dai 3; Yong Joong Lee 4
1 European Spallation Source ERIC 2 Div. of Materials Engineering, Lund University 3 Paul Scherrer Institut 4 ESS
Corresponding Author: [email protected]
Thermal properties of pure tungsten, irradiated in the Swiss neutron spallation source at thePaul Scherrer Institut, have been studied in the temperature range 25-500 ℃. Disk-shaped specimens were prepared from a tungsten sheet which was irradiated with approximately 550 MeV protons. The specimens tested in this work received total damages of maximum 3.9 and 5.8 dpa ataverage irradiation temperatures of 115 and 140 ℃, respectively. The thermal diffusivity of the irradiated tungsten was measured using the conventional flash method. For both specimens, the results show a significant decrease in thermal diffusivity after irradiation; attaining a value of around 35mmˆ2/s throughout the test temperature range. Relative to unirradiated tungsten, the irradiated samples show thermal diffusivity values which are 28-51% lower, depending on temperature. Annealing of the irradiated specimen at 1000 ℃ for 1 h resulted in a slight recovery of thermal diffusivity. In addition, thermal conductivity values were calculated from the observed thermal diffusivity data. The effect of decreasing thermal conductivity on the of dynamic thermal stress in the targetofthe European Spallation Source has also been studied.
Session 5-Target Facility Challenges / 44
SNS Hot Cell Design Philosophy
Author: Michael Dayton1
1 ORNL-SNS
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Corresponding Author: [email protected]
ORNL’s Spallation Neutron Source (SNS) utilizes liquid mercury as its spallation target material. The requisite infrastructure to support the operation and maintenance of the mercury process system must be reliable and robust to support safe neutron production operations, yet versatile and flexible to react to contingencies and adapt to changing operational requirements. Due to the unique hazards associated with liquid mercury, the entire process system is housed within a heavily-shielded hot cell. The philosophy of the SNS hot cell design is predicated on fully remote operations with nohands-on human involvement. Basic details of the hot cell design itself will be covered highlighting features that support both the facility safety basis and the nominal operational requirements. All aspects of hot cell operation and maintenance rely on the use of a complex dual-arm servomanipulator system supplemented by conventional master-slave through-the-wall manipulators and an in-cell overhead crane. Design and operational features of the servomanipulator system will be discussed. An overview of nominal hot cell operations will be discussed along with the expanding role of Post- Irradiation Examination (PIE) and mercury process system enhancements. Significant operational experience has resulted in an evolution of the operational philosophy since initial beam-on-target in 2006. A discussion of this evolution and the hardware and operational risks associated with this design philosophy will be presented.
Session 5-Target Facility Challenges / 45
Design and Operation of the Mu2e Target Remote Handling Sys- tem
Author: Michael Campbell1
1 FNAL
Corresponding Author: [email protected]
The Mu2e experiment currently being designed and built at Fermilab will utilize a small tungsten target located in the middle of a long cylindrical vacuum chamber, which is then located inside a large superconducting solenoid. The radioactivity level of the target is very high at 3.3kSv/hr (contact) and the frequency for replacing this target is planned to be once per year. To perform this task, a remote handling system is being developed at Fermilab that utilizes 2 robotic machines - one to remove/replace the access window, and another to remove/replace the target. The design of the Mu2e remote handling system will be presented. Additionally, the most recent progress made to build the target handling machine will be discussed, including videos of the machine in autonomous operation both installing and removing targets.
Poster Session and Reception / 46
Ion irradiation damage in commercially pure Titanium and Ti- 6Al-4V: Characterization of the microstructure and mechanical properties
Author: AIDA Amroussia1 Co-authors: Boopathy Kombaiah 2; Clara Grygiel 3; Daniel Robertson 4; Edward Stech 4; Florent Durantel 3; Frederique Pellemoine 5; Isabelle Monnet 3; Mikhail Avilov 6; Tan Ahn 4; Wolfgang Mittig 7; carl boehlert 8
1 MICHIGAN STATE UNIVERSITY 2 Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 3 CIMAP-CIRIL, BP 5133, 14070 CAEN CEDEX 5, France 4 Department of Physics, University of Notre Dame, Notre Dame, IN 46556 5 Michigan State University - Facility for Rare Isotope Beams
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6 FRIB Michigan State University 7 MSU-NSCL 8 michigan state university
Corresponding Author: [email protected]
Due to their low activation, corrosion resistance, good mechanical properties, and their commercial availability, Ti-alloys, especially the α+β alloy Ti-6Al-4V (wt%), are considered for different applica- tions in nuclear industry. Ti-6Al-4V is also being considered as a structural material for the beam dump for the Facility for Rare Isotope Beams (FRIB) at Michigan State University- a new generation accelerator with high power heavy ion beams. In this study, samples of commercially pure (CP) Ti and Ti-6Al-4V that were processed through two different thermomechanical processes: powder metallurgy (PM) rolled and additive manufacturing (AM) were utlilized. The as-received samples exhibited two distinctly different microstructures. The powder metallurgy (PM) rolled sample had equiaxed α-phase grains with the β-phase typically present at the grain boundaries whereas the additive-manufactured sample showed a lamellar α +β microstructure. The samples were irradiated at Notre Dame University using 4 MeV Ar ion beam at 25℃ and 350℃. For the samples irradiated at RT, similar final dose of 7.3 dpa within the depth of 1 µm from the surface was obtained usingtwo different dose rates of 0.8 dpa/h and 13.4 dpa/h. Nano-indentation measurements were carriedout on the surface of the bulk samples to estimate the irradiation hardening. While CP-Ti exhibited the highest irradiation induced hardening, the nano-hardness of the additive-manufactured Ti-6Al-4V was found to be sensitive to the dose rate effect. To better understand the defect structure in the ir- radiated samples, 3 mm thin foils were prepared for the ongoing Transmission Electron Microscopy (TEM) characterization.
Session 3-Post Irradiation Examination / 47
Post-irradiation examinations of SINQ Target-11
Author: Yong Dai1
1 Paul Scherrer Institute
Corresponding Author: [email protected]
SINQ Target-11 was in operation in 2015 and 2016. It was shut-down due to an incident in June 2016, during which the pressure drop in the cooling water loop increased significantly, and meanwhile, the activity of the cooling water also increased tremendously. The evidence indicated a serious failure of the target. As this is the first severe failure since SINQ was in operation in 1997, the target hasto be investigated by detailed post-irradiation examinations (PIE). The target was opened in a hot-cell next to the SINQ target station (ATEC) in June2017.After removing the AlMg3 safety container, it was observed that lead (Pb) was melted and leaking out from the bottom of the target-block. The empty tubes in the first row of the target werebroken. During extracting some target rods for PIE, it was found that the rods in the lower part of the target could not be pulled out. This implies the core of the target was broken and the Pb was meltedand froze the rods in this part. The rods/tubes selected for PIE are those which could be removed from the target and whichhavea relatively high irradiation dose. Neutron radiography inspection was conducted to reveal the status of Pb in the rods. Afterwards, these rods/tubes were sent to PSI’s hot laboratory for detailed PIE, including: (1) Hardness measurement, (2) Metallography (with etching for viewing hydrides), (3) Electron Probe Microanalysis (EPMA), (4) Ring compression and tension testing, (5) Transmission Electron Microscopy (TEM) observations. Up to date, the first three PIE items have been done. In this presentation the available results will be shown in detail and the potential failure mechanisms will be briefly discussed.
Session 1-R&D to Support Concepts / 48
Optimization of the LBNF Neutrino Beam
Page 19 2018 High Power Targetry Workshop / Book of Abstracts
Author: Laura FieldsNone
Corresponding Author: [email protected]
The Long Baseline Neutrino Facility (LBNF) will use high energy protons impinging on agraphite target to produce kaons and pions, which will be focused by a set of magnetized focusing horns and directed into a decay pipe where they will decay, producing an intense neutrino beam. The neutrino energy spectrum can be tuned by changing a variety of parameters in the beamline such as horn and target shapes. Recent advances in computing power coupled with the development of complex optimization algorithms enable identification of parameters that are precisely tuned to optimize physics parameter sensitivity. An optimization of the LBNF beam parameters for sensitivity to CP violation has been performed. The resulting beam design and its physics performance will be discussed, as well as engineering modifications to that design and re-optimization incorporating these engineering constraints.
Session 1-R&D to Support Concepts / 49
RaDIATE thermal shock experiments at CERN’s HiRadMat facil- ity
Author: Kavin Ammigan1
Co-authors: Andrew Casella 2; Chris Densham 3; Claudio Torregrosa 4; David Senor 5; Eiichi Wakai 6; Glenn Waver 7; Katsuya Yonehara 7; Keith Anderson 7; Keith Kershaw 4; Marco Calviani 4; Mark Butcher 4; Patrick Hurh 8; Regis Seidenbinder 4; Shunsuke Makimura 9; Sujit Bidhar 8; Taku Ishida 9; Viacheslav Kuksenko 10
1 Fermi National Accelerator Laboratory 2 PNNL 3 STFC Rutherford Appleton Laboratory 4 CERN 5 Pacific Northwest National Laboratory 6 JAEA 7 Fermilab 8 FNAL 9 J-PARC/KEK 10 University of Oxford
Corresponding Author: [email protected]
With increasing beam intensities of future accelerator facilities, it is critical to understand the ther- mal shock response of conventional and novel materials used as accelerator beam windows and secondary particle production targets in order to successfully design and operate these components. As a result, experiments initiated by the RaDIATE collaboration, have been carried out and are be- ing designed at CERN’s HiRadMat facility where single-shot high intensity proton beams probe and investigate the thermal shock response and limit of relevant materials. The BeGrid (HRMT24) exper- iment, composed of various grades of beryllium specimens and exposed to varying beam intensities, was successfully executed in 2015. Results from the BeGrid Post-Irradiation-Examination (PIE) work and numerical simulation benchmarking efforts will be presented in this talk. In addition, an update on the upcoming BeGrid2 (HRMT43) experiment will be provided. The BeGrid2 experiment will be carried out later this year and will comprise of conventional accelerator materials as well as novel electro-spun nano-fiber materials. The difference in thermal shock response of non-irradiated and previously irradiated specimens will be investigated, as well as real-time measurements of beam- induced dynamic stresses.
Poster Session and Reception / 50
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Last updates of the R&D activities for the redesign of the CERN’s AD-Target
Author: Claudio Torregrosa Martin1 Co-authors: Antonio Perillo-Marcone 1; Joao Canhoto Espadanal 1; Lucian-Mircea Grec 1; Marco Calviani 1; Mark Butcher 1; Nicola Solieri 1; Romain Ferriere 1
1 CERN
Corresponding Author: [email protected]
This study presents the last updates regarding the R&D activities for the redesign of theCERN’s Antiproton Decelerator (AD) production target, which are taking place in the context of the AD- Target area Consolidation project. These updates include the manufacturing of a first scaled prototype of the target, constituted bya sliced core of 8 mm diameter Ta rods embedded in a compressed expanded graphite (EG) matrix, and its testing under proton beam impacts at the CERN’s HiRadMat facility in 2017, within the so called HRMT-42 experiment. The experiment counted on online instrumentation recording the velocity at the target´s periphery, providing information of its dynamic response and damping properties of the EG matrix. Furthermore, x-ray and neutron topographies have been complementarily used to inspect the target after irradiation, suggesting that the EG matrix can successfully adapt tothe swelling of the Ta core due to extensive plastic deformation induced by the dynamic stresses. The neutron tomography reveals the presence of voids inside the Ta core, differently from what it was observed in the previous HiRadMat experiment (HRMT-27), in which the Ta was subjected to only a few high intensity pulses. Following the guidelines drawn by this and previous experiments, the current configuration of the new AD-Target design is presented, including its pressurized air-cooled Ti-6Al-4V envelope. In addition, the PROTAD-HiRadMat experiment -foreseen in 2018- is introduced. This experiment will aim at testing six prototypes of such new design, containing different core geometries and mate- rials configurations, as a last step for its final validation before installation in the areain2020.
Session 5-Target Facility Challenges / 51
Preliminary design study of the integration and remote handling processes for the Beam Dump Facility Target Complex
Authors: Edmundo Lopez Sola1; Jean-Louis Grenard1; Keith Kershaw1; Marco Calviani1
1 CERN
Corresponding Author: [email protected]
CERN has launched a work programme to evaluate the feasibility of a new facility for fixed target physics and dark matter searches (the “Beam Dump Facility”, BDF). In the proposed facility, apro- duction target/dump, will be capable of absorbing the entire energy of the beam extracted from the Super Proton Synchrotron. The target will produce weakly interacting particles for investigation by a suite of particle detectors downstream of the target complex. High levels of radiation (both prompt and residual) will be produced: the total cumulated dose fore- seen near the target is around 500 MGy/year. The target will be underground and all handling op- erations on the target and surrounding equipment will be carried out remotely. The target complex will house the target and its services; a new extraction tunnel and an experimental complex will complete the BDF. Conceptual design work on the target complex had previously been carried out at CERN in support of a technical proposal to obtain funding for the current BDF study phase. The first goal of the preliminary design study covered by this presentation was to demonstrate the feasibility of the construction, operation, maintenance of the BDF target complex. The second goal of the study was to produce integration-level designs of the target complex to allow development of
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civil engineering designs and further design of technical services by other specialist teams as part of the work to evaluate the feasibility and estimated cost of the BDF facility. The study has been conducted with the support of an external remote handling design company working in close collaboration with CERN. After briefly introducing the BDF, the presentation out- lines organisation of the study then describes the resulting target complex designs. Further work, currently underway, to complete the integration design for the CDR is introduced.
Session 1-R&D to Support Concepts / 52
Beam Dump Facility target: design status, beam tests in 2018 and material studies
Author: Edmundo Lopez Sola1
Co-authors: Antonio Perillo-Marcone 1; Heinz Vincke 1; Josep Busom Descarrega 1; Keith Kershaw 1; Marco Calviani 1; Matthew Fraser 1; Mirkoantonio Casolino 1; Pietro Avigni 1
1 CERN
Corresponding Author: [email protected]
The Beam Dump Facility (BDF) Project, currently in its design phase, is a proposed general-purpose fixed target facility at CERN, dedicated to the Search for Hidden Particles (SHiP) experiment inits initial phase. At the core of the installation resides the target/dump assembly, whose aim is to fully absorb the high intensity 400 GeV/c SPS beam and produce charmed mesons for the SHiP experiment. In addition to high thermo-mechanical loads generated by the pulsed beam, the most challenging aspects of the proposed installation reside in very high energy and power density deposition that are reached during operation. In addition, 320 kW are deposited in the target/dump assembly. In order to validate the design of the BDF target, a scaled prototype is going to be tested during 2018 in the North Area at CERN, upstream the existing beryllium primary targets, with an expected deposited power of 20 kW. The prototype testing under representative beam scenarios will permit an insight of the material response in an unprecedented regime. Online monitoring and an extensive Post Irradiation Experimental (PIE) campaign are foreseen. A complementary extensive material R&D is carried out in parallel, dedicated to the study of cladded refractory metal targets, and focusing mainly in the performance of the bonding between the cladding and core materials. The current contribution will detail the design of the BDF target/dump core and the designand construction of the prototype target assembly, as well as the ongoing R&D studies on cladded targets, including an insight of radiation damage effects.
Session 6-Construction, Fabrication, Inspection, Quality Assurance / 53
Detailed design, prototyping activities and beam irradiation tests for the new n_TOF neutron spallation target
Author: Marco Calviani1
Co-authors: Antonio Perillo-Marcone 1; Marc Timmins 1; Raffaele Esposito 1; Rui Franqueira Ximenes 1; Vincent Maire 1
1 CERN
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Corresponding Author: [email protected]
A third-generation neutron spallation target for the CERN neutron time-of-flight (n_TOF) facility is currently in the detailed design and prototyping phase. This “atypical” neutron source is subjected to short (7 ns) and high-intensity (1*1013 ppp) proton pulses, resulting in extremely high dynamical effects. Construction is foresee in 2019 and installation in 2020. The design focuses on improving reliability, increasing average and instantaneous proton intensity on target and avoiding some issues encountered in the current target, among which the contamina- tion of cooling system water with radioactive spallation products and creep phenomena. After a preliminary design and initial prototyping stage, a design review on different design solu- tions took place in June 2017. A subsequent detailed design stage is ongoing for two solutions. They consist in a water-cooled Ti-6Al-4V-contained pure Pb monolithic target core as well as in a nitrogen cooled pure Pb massive slices. This contribution details the following intimately related aspects, which are critical for the success of the Project:
1. Prototyping activity carried out to optimize the cladding process between Ti-6Al-4V and Pb, in order to guarantee the required heat dissipation from the target core; 2. Robustness studies for accidental scenarios (interruption of water circulation, loss of contact at the interface between Ti-6Al-4V and Pb); 3. Design of a beam irradiation test on target prototypes in the HiRadMat facility at CERN, in order to validate the different design solutions, which will take place in August 2018.
Session 1-R&D to Support Concepts / 54
Research of Materials in Target Environment at European Spalla- tion Source
Author: Yong Joong Lee1
1 ESS
Corresponding Author: [email protected]
The ESS Target Station consists mainly of proton beam intercepting systems and other components exposed to high intensity radiation. The functionalities of these systems degrade with accumulated radiation damage in the constituent materials. It is important to have a clear understanding of prop- erties of irradiated materials in making the materials selections and the operations and maintenance plan of the facility. At the European Spallation Source (ESS), a number of research projects on irra- diated materials are undergoing. The research program includes post irradiation examination (PIE) of tungsten as spallation material, PIE of aluminum alloys as proton beam window material, charac- terization of beryllium as reflector material, in-beam characterization of chromium doped alumina as luminescent coating material, chemical kinetics of selected catalyzers for ortho-to-para hydrogen conversion, and PIE of radiation resistant elastomer and lubricants. A number of irradiation cam- paign and PIE activities are in progress, in collaboration. In this presentation, current status of the materials research projects is reported. Furthermore, a prospect of future materials research in the target environments at ESS is presented.
Session 4-Target Design, Analysis, Validation of Concepts / 55
In-situ studies of phase transition related Pb transport in the SINQ target rods with use of the NEUTRA imaging instrument at PSI
Page 23 2018 High Power Targetry Workshop / Book of Abstracts
Author: Sergejs Dementjevs1
Co-authors: Bertrand Blau 1; Daniela Kiselev 1; Michael Wohlmuther 1; Normunds Jekabsons 2; Peter Vontobel 1
1 Paul Scherrer Institut 2 Latvia University
Corresponding Author: [email protected]
The key element in the SINQ target of the neutron spallation source at the Paul Scherrer Institute (PSI) is a bundle of rods fabricated from Zr-alloy tubes filled with Pb. A proton beam initiates a spallation reaction, which is accompanied with a powerful local heat release (mainly in Pb). Despite an effective convective cooling of the rods surfaces with heavy water, the temperature ofPb in some rods may rise above the Pb melting point. Our measurements of temperatures in the SINQ targets rods bundles (in Pb and in heavy water) confirm this assumption. Our laboratory experiments (in which the processes occurring in the rod are visualized by means of the NEUTRA imaging instrument in SINQ) show that the process of Pb melting – solidification is accompanied by migration of Pb inside the rods. Neutron images of some of the irradiated rods from dismantled rods bundles assemblies of decommissioned targets show a similar pattern. An initial study of phenomena is performed. Both, experiments and simulations, show, that the Pb migration can create conditions leading to mechanical stressing and plastic deformation of the Zr- alloy tubes due to internal pressure from Pb. Some aspects of stress-strain state and mass transport were simulated and findings were compared with the experiments. The paper discusses the method and results of the temperature measurements during theopera- tion of SINQ targets; method and results of laboratory experiments aimed at studying of possible physical mechanisms of the Pb migration in the rods and of the Zr-alloy pipes stressing and plastic deformation.
56
Thermo-mechanical analysis of NuMI Horn-1 for NuMI upgrade AIP
Author: Yun He1
Co-author: Cory Crowley 1
1 Fermi National Accelerator Lab
Corresponding Author: [email protected]
This report gives a summary of thermo-mechanical analysis of the NuMI Upgrade AIP focusing Horn- 1 for operating at a maximum beam power of 1 MW. The Horn-1 is identical to the one currently running at 700 kW for NOvA beam operations. Horn cooling radioactive water (RAW) system will be upgraded for removing the increased heating loads. Horn conductors must be able to endure combined thermal loads from electrical resistive heating due to Joule losses and beam heating due to secondary particle interactions with the materials. In addition, current pulsing generates electromagnetic forces on the conductors. Horns are required to withstand repetitive thermal and magnetic loadings over millions of current/beam pulses. The analysis are performed with ANSYS, and include temperature and stress studies for several load- ing scenarios: steady state, immediately after beam spills, immediately after current pulse, current pulsing only, thermal loading only, and beam cold start-up. The horn fatigue strength is evaluated for 100 million pulses.
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Session 2-Radiation Damage in Target Material and Related Simulations / 57
IAEA Activities in Support of the Accelerator Based Simulation and Modelling of Radiation Damage Effects
Author: Danas Ridikas1
Co-authors: Ian Swainson 1; Sehila Sehila Gonzalez-De-Vicente 1
1 IAEA
Corresponding Author: [email protected]
Promotion of nuclear applications for peaceful purposes and related capacity building is among the missions of the IAEA. In this context, accelerator applications and nuclear instrumentation is one of the thematic areas, where the IAEA supports its Member States in strengthening their capabilities to adopt and benefit from the usage of accelerators. A number of activities are being implemented focusing on accelerator based research and applications in multiple disciplines, facilitating access to accelerator facilities for the countries without such capabilities, and also development and capacity building in associated nuclear instrumentation. Specifically, under the topical area of this workshop “Radiation Damage in Target Material and Related Simulations”, some results will be reported on ion beam irradiation as a promising technique capable of emulating the effects of radiation damage in fission and fusion reactors, and therefore as a possible rapid screening technique prior toin-core testing. (for an extended abstract please see attached file)
Session 8-Multipurpose Use of Targets and Beam Dumps / 58
Physics Beyond Colliders at CERN
Author: Mike Lamont1
1 CERN
Corresponding Author: [email protected]
It is an interesting time for particle physics. There is strong evidence for Dark Matter, and little sign of deviations from the Standard Model at the LHC. This is fermenting a growing interest in precision studies and searches for novel forces at wide range of energies and couplings. In 2016 CERN established a Physics Beyond Collider initiative, an exploratory study aimed at exploiting the full scientific potential of CERN’s accelerator complex and its scientific infrastructure through projects complementary to the LHC, HL-LHC and other possible future colliders. Following an brief recap of the motivations, an overview of the options being explored is presented. These range from a beam dump facility, an all-electrostatic ring to measure the electric dipolemo- ment of the proton, to solar axion searches. Particular attention is given to the fixed target options which primarily aim to harness the potential of the SPS.
59 Multi-Physics coupling to model the TMRS Mark IV Middle Tung- sten Target Stack
Author: Eric Olivas1
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Co-authors: Joel Montross 1; Keith Woloshun 2; Michal Mocko 1
1 Los Alamos National Laboratory 2 LANL
Corresponding Author: [email protected]
A computational model has been developed to simulate the thermal hydraulic and thermal mechan- ical performance of the LANSCE TMRS Mark IV Middle Tungsten Target Stack, which consists of six tungsten targets that are 10.16 cm in diameter and vary in thickness that are tantalum cladded. Target cooling gaps of 1.524 mm separate the target disks, while water flows at 690 cc/sec at an inlet pressure of 1.37 MPa. The methodology involves coupling particle transport, thermal hydraulic and thermal mechanical codes to determine the thermal hydraulic and thermal mechanical behavior of the target stack to optimize target performance.
Session 4-Target Design, Analysis, Validation of Concepts / 60
The LIEBE high-power target: Offline commissioning results.
Author: Ferran Boix Pamies1 Co-authors: Alexandre Beynel 1; Andres Veitez Suarez 1; Antje Behrens 1; Donald HOUNGBO 2; Ferran Barozier 1; Kalvis Kravalis 3; Laurent Prever-Loiri 1; Linards Goldsteins 3; Lucia Popescu 2; Lukasz Lacny 1; Melanie Delonca 1; Michael Guinchard 1; Susanta Lahiri 4; Tania Melo Mendonca 5; Thierry Feniet 1; Thierry Stora 1
1 CERN 2 SCK-CEN 3 IPUL 4 Saha Institute of Nuclear Physics 5 CERN - European Organization for Nuclear Research
Corresponding Author: [email protected]
With the aim of increasing the primary beam intensity in the next generation of Radioactive Ion Beam facilities, a major challenge is the production of targets capable of dissipating the high de- posited beam power. In that context, LIEBE is a high-power target dedicated to the production of short-lived isotopes. The design consists of a loop of molten lead-bismuth eutectic, in which the deposited primarybeam power is dissipated by a water-cooled heat exchanger. The circulation of the liquid metal is achieved by an electromagnetic pump coupled to the loop. Additionally, the target includes a diffusion cham- ber next to the irradiation chamber to promote the creation of droplets through a grid. The extraction of short-lived isotopes is then enhanced by the shorter diffusion paths of the droplets compared to the ones of a liquid bath. The LIEBE prototype is now fully assembled and before operating the target online at ISOLDE, the safety and operation conditions have to be reviewed. An offline commissioning phase has started, in which several non-conformities could be identified and solved. The flow established by theelec- tromagnetic pump has been evaluated in a LIEBE replica, the stability of the target/pump coupling has been assessed through alignment and vibration measurements and the thermal control system has been tested. The final test will foresee the full operation of the prototype on the offline isotope separator.
Session 1-R&D to Support Concepts / 61
Tungsten Oxidation AeroSol Transport (TOAST) Experiments
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Author: Per Nilsson1
Co-authors: Anders Gudmundsson 2; Jens Klingmann 2; Karin Loven 2
1 European Spallation Source 2 Lund University, Faculty of Engineering
Corresponding Author: [email protected]
The TOAST experiments were performed to investigate how much tungsten becomes airborne by tungsten oxidation at temperatures up to above 1400 C. The mass fraction of the oxidised amount that is airborne after passage through the system, was measured to be up to50%. In these experiments, large tungsten blocks of 0.25 - 0.5 kg are oxidised, compared to the smaller filaments or rods such as used in other tungsten oxidation experiments described in the references. The blocks are inductively heated in a controlled air flow with speeds of the order of1m/s.Then the oxide laden flow is led through an about 4 m long system of 1.5 inch stainless piping, whichhas similarities with a possible escape path from a high power spallation target. The piping has vertical and horizontal sections as well as several bends, in order to promote and study aerosol deposition by different phenomena. A HEPA filter is placed at the end of the system. The blocks and the filter are weighed beforeandafter the tests in order to calculate the release fraction. Several other variables are measured in the tests, such as block and air temperature and wall deposition. The aerosols are measured with an impactor at the end of the system and by a Fast Aerosol Mobility Size Spectrometer at two extraction points in the system. Transmission Electron Microscopy is also used to study the generated particles. The purpose of the tests is to simulate bulk conditions, i.e. full size and flow, hence the largeblocks. The conditions are intended to be realistic for highly improbable accident events in neutron spalla- tion targets, i.e. events were the beam is continuously on and no safety systems or confinements are functional.
Poster Session and Reception / 62
Diffusion of tritium produced in a graphite and SiC target
Author: Naritoshi Kawamura1
Co-authors: Atsushi Yabuuchi 2; Shiro Matoba 1; Shunsuke Makimura 3
1 KEK/J-PARC 2 Kyoto University 3 J-PARC/KEK
Corresponding Author: [email protected]
Tritium is known to be generated in a target material like graphite by a nuclear reaction due to hadron beam irradiation. It is pointed out that such a tritium diffuses in the high temperature graphite exposed by a high power beam, and then evaporates to the beam line vacuum. Hence such a tritium has possibility to cause an unexpected leakage and/or contamination trouble. In a sense of radiation safety, the knowledge of tritium diffusion is essential to develop the target inhigh power beam facilities like J-PARC Muon Facility. As a candidate material of the first wall of nuclear fusion reactor, many studies were performed on the hydrogen isotope diffusion in graphite, although the diffusion coefficient shows thestrong dependence on samples, i.e. single or poly crystal, grain size of crystal, concentration of the va- cancies and so on. Such sample dependence can be explained by the tritium diffusion through the grain boundaries and trap in the vacancies. However, we are still far from the comprehensive and quantitative understanding, and this puts an uncertain risk factor to the development of the next- generation target system as well as the operation trouble at present. We are planning to perform a study of hydrogen isotope diffusion in graphite using a muon and
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a positron beam. A positively-charged muon injected into a material acts as a light isotope of hy- drogen, and thus muon informs the microscopic behavior of the hydrogen isotope. In addition, a positron gives the information about the concentration of the hydrogen trapped in a vacancy by the change in its life time due to the enhancement of annihilation by the trapped hydrogen. We will present the details of the planned study about the hydrogen isotope diffusion in graphite and also SiC.
Poster Session and Reception / 63
Exploratory study for the production of Sc beams at the ISOL fa- cility of MYRRHA
Author: Martin Ashford1 Co-authors: Donald HOUNGBO 2; Hamid Ait Abderrahim 2; Lucia Popescu 2; Marc Dierckx 1
1 SCK•CEN 2 SCK-CEN
Corresponding Author: [email protected]
The design of high-power targets for production of Radioactive Ion Beams (RIBs) at an IsotopeSep- aration On-Line (ISOL) facility requires a full overview of the physical processes occurring in the target: nuclear reactions, thermal effects, isotope diffusion and effusion. Such high-power targets are nowadays a requisite as they constitute one of the means to significantly increase the yields of certain RIBs to the levels required by the users. In the first phase of the MYRRHA project, the ISOL@MYRRHA facility will make use of a high-power proton beam (100-MeV & 0.5 mA) in combi- nation with high-power targets in order to produce high intensity RIBs of various isotopes. These high power targets require specific R&D to tackle engineering challenges like heat dissipation issues while maintaining the high isotope yields that are obtained with thick targets. For this, an algorithmic method is in development that will combine the particle transport calcu- lations, thermo-mechanical simulations, and an isotope release model, in order to determine the optimal target design for the production of a specific isotope. In this contribution, the exploratory study for the production of Sc beams at the ISOL facility of MYRRHA will be presented. The short lived isotopes like 41Sc would be of interest for beta-decay spectroscopy while the long lived ones like 44,47Sc are useful for medical applications.
Session 6-Construction, Fabrication, Inspection, Quality Assurance / 64
Neutron Source Manufacturing at SNS
Author: Peter Rosenblad1
1 Oak Ridge National Laboratory
Corresponding Author: [email protected]
The Source Development and Engineering (SDE) group at the Spallation Neutron Source (SNS)is responsible for all engineering aspects of neutron source components. This includes research and development, conceptual design, detailed design and analysis, manufacturing, operations support, and post irradiation examination. Within the group, a manufacturing team is dedicated to procuring the specialized source components. These components are primarily Target Modules, Inner Reflector Plugs, and Proton Beam Windows. In all cases, there are an array of specialized manufacturing processes required to complete the components, including electron beam (EB) welding, wire electron discharge machining (EDM), conventional EDM, gun drilling, and complex conventional machining. Experience has proven that these components are too complex for a hands off procurement approach. Therefore, SDE manufacturing team members are integrally involved in the development ofthe
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processes and provide extensive oversight and quality assurance through completion. This paper will describe the processes used to by the SDE manufacturing team. It will describe some of the historical challenges that the team has overcome. Finally, it will outline manufacturing plans and changes that are planned in the future.
Session 2-Radiation Damage in Target Material and Related Simulations / 65
J-PARC neutrino beam-line and radiation damage studies on Ti- tanium alloys
Author: Taku Ishida1
1 J-PARC/KEK
Corresponding Author: [email protected]
I will overview the operational status of the J-PARC neutrino beam-line since last HPTW meeting (2016), and will present upgrade prospect towards >1MW beam operation. I also present about the status and plan of radiation damage studies on Titanium alloys led by RaDIATE collaboration.
Session 7-Operation of Targets and Beam Dumps / 66
Target system maintenance experience in hot cell at J-PARC
Author: Hidetaka Kinoshita1
Co-authors: Hiroshi Takada 1; Hiroyuki Kogawa 1; Katsuhiro Haga 1; Makoto Teshigawara 1; Takashi Naoe 1; Takashi Wakui 1; Tetsuya Kai 1
1 Japan Atomic Energy Agency
Corresponding Author: [email protected]
At the Japan Proton Accelerator Research Complex (J-PARC), a mercury target system has been in operation as a neutron production target of the spallation neutron source driven by 3-GeV protons. It is loaded on a big target trolley that has a dimension of 12.2 m in length, 2.6 m in width and 4 m in height and moves horizontally on a rail in a hot cell. The volume of the hot cell is as large as L43 × W12 × H15 m. Half area of the hot cell is used for the maintenance of the mercury target system and the floor is covered by a stainless lining considering a leak of liquid mercury. Theother half area is used for the replacement of the proton beam window and moderators. Target vessel replacement is performed with full-remote handling devices such as a 6-axis power manipulator, 3 pairs of master/slave manipulators, an in-cell overhead 20 t crane and radiation resistant cameras. Since a large amount of radioactive gaseous nuclides are generated in mercury via the spallation reactions, they should be transferred from the surge tank of the mercury circulation system to an off-gas processing system before removing the used target vessel. The off-gas processing systemis installed in a room nearby the hot cell. It is also operated during target replacement work to suppress the release of tritium in the mercury target system to open air . The used target vessel is contained in a stainless steel container and moved to a storage room on the basement floor with the overhead crane. More detailed design of hot cell and experiences on the target system maintenance will be presented.
Session 4-Target Design, Analysis, Validation of Concepts / 67
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The ESSnuSB Target Station
Author: Piotr Cupial1
Co-authors: Elian Bouquerel 2; Eric Baussan 2; Etam Noah 3; Jacques Wurtz 2; Marcos Dracos 2; Nicolaos Vas- silopoulos 4; Pascal Poussot 2
1 AGH University of Science and Technology, Krakow, Poland 2 IPHC/CNRS, Universite de Strasbourg, France 3 University of Geneva, Switzerland 4 Institute of High Energy Physics, Beijing, China
Corresponding Author: [email protected]
The ESSνSB project, recently granted by the EU H2020 programme for a 4-year design study,pro- poses to use the protons produced by the linac (2 GeV, 5 MW) of the European Spallation Source (ESS) currently in construction in Lund (Sweden) to deliver a neutrino super beam. It follows the studies made by the FP7 Design Study EUROν[1] (2008-2012), regarding future neutrino facilities. The primary proton beam line completing the linear accelerator will consist of one or several accu- mulator rings and a proton beam switchyard. The secondary beam line producing neutrinos will consist of a four-horn/target station, a decay tunnel and a beam dump. A challenging component of this project is the enormous target heat-load generated by the 5 MW proton beam. In order to reduce this heat-load there will be four targets, which will be hit in sequence by the compressed proton pulses, thereby reducing the beam power on each target to 1.25 MW. Following the EUROν studies, a packed bed of titanium spheres cooled with helium gas has become the baseline design for a Super Beam based on a 2-5 GeV proton beam with a power of up to 1 MW per target, with other targets being considered for comparison. The hadron collection will be performed by four hadron collectors (magnetic horns), one for each target. Each of these target/hadron-collector assemblies will receive proton pulses three times more frequently than in present projects, and by an average beam power of 1.25 MW, which is twice as high as in present neutrino projects. The feasibility of the target/horn station for the ESSνSB project is discussed here.
Session 3-Post Irradiation Examination / 68
Techniques and Accomplishments of the Post Irradiation Exami- nation Program at the Spallation Neutron Source
Author: David McClintock1
1 Oak Ridge National Laboratory
Corresponding Author: [email protected]
During operation several components at the Spallation Neutron Source (SNS) are exposed to high energy radiation that alter mechanical and physical properties, which limits their useful lifetime. Components are also occasionally removed from service due to leaks or another failure mechanisms that prohibit reliable operation. The SNS maintains a rigorous post irradiation examination (PIE) pro- gram, and have developed a wide array of capabilities to sample and inspect irradiated components after service. Techniques developed include remote sampling of components, videoprobe inspec- tion, remote identification of leak locations, high-resolution hotcell photography, and non-contact topography characterization. These techniques have provided invaluable information on component performance to design engineers and management, which have facilitated improved component de- signs and more predicable operation. This presentation will outline the PIE techniques utilized at the SNS and summarize some of the impacts the results have had on operation of the SNS.
Session 2-Radiation Damage in Target Material and Related Simulations / 69
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The Influence of High Energy Proton Irradiation on Fine-Grained Isotropic Graphite Grades: A Summary of Recent RaDIATE Re- sults
Author: Patrick Hurh1
Co-authors: Andrew Casella 2; David Senor 3; Dong Liu 4; Kavin Ammigan 5; Nikolaos Simos 6
1 FNAL 2 PNNL 3 Pacific Northwest National Laboratory 4 Oxford University 5 Fermi National Accelerator Laboratory 6 BNL
Corresponding Author: [email protected]
Fine-grained isotopic graphite has become a material of choice for neutrino beam targets subjected to high energy, pulsed proton irradiation, such as the NuMI-NOvA beamline with 700 kW of pri- mary beam power. Graphite has been chosen for its stability at high temperature, the physical and mechanical properties that make it particularly resilient to thermal shock conditions, and low atomic mass that helps generate a high yield of secondary particles with the desired energy spec- trum for the downstream neutrino experiments. However, the physical and mechanical properties are highly affected by the irradiation conditions, impacting the expected lifetime of the target mate- rial, especially considering the higher beam powers of near-future neutrino beamlines, such as the LBNF-DUNE beamline with up to 2.4 MW of primary beam power. Selected results of radiation dam- age studies on graphite conducted by RaDIATE researchers over the past decade will be presented. Significant changes in physical and mechanical properties (e.g. 60-80% increase in elastic modulus) and lattice swelling are reported and shown to be highly irradiation temperature dependent. The results, especially lattice swelling, are shown to be very similar to those from reactor based irradia- tions. These results indicate that data from previous reactor low-energy neutron irradiation studies can be correlated to the high-energy proton irradiation regime, as well as quantitatively reinforce the conclusion that correct selection of the operating temperature for a graphite target is critical to maximizing the target lifetime.
Session 8-Multipurpose Use of Targets and Beam Dumps / 70
Compact Sealed lithium target for accelerator-driven BNCT sys- tem
Author: Kazuki Tsuchida1
Co-author: Yoshiaki Kiyanagi 1
1 Nagoya University
Corresponding Author: [email protected]
An accelerator-based neutron source for Boron Neutron Capture Therapy is under developing with a combination of a DC accelerator (IBA Dynamitron, 2.8MeV, 15mA) and a compact sealed lithium target. Low energy protons incident on lithium target are one of the most suitable reaction for accelerator-based BNCT. However, metallic lithium has several difficulties in chemical properties (low melting point, high chemical activity and 7Be production) as a target material. For resolving those issues, we are developing a compact and sealed Li target. The sealed lithium target contains a thin lithium layer (2mm) between a thin titanium foil and an embossed structure on a tantalum base plate. Then, the liquid lithium and radio isotopes (Be-7, T) can be confined in the target.The low-energy and high current proton beam is passing through a titanium foil and irradiated to the lithium layer. Such a high beam flux (More than 7MW/m2) can be removed by a strong turbulent flow arose with ribs in cooling water channels of the target.
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Neutrons with the energies of less than 1MeV are produced due to the 7Li(p,n)7Be reaction by the irradiation of the 2.8MeV proton beams and could be moderated using a compact beam shaping assembly to meet all the conditions indicated in the IAEA-TECDOC-1223. Sealed lithium target will be replaced routinely after cancer treatments of more than one hundred by a remote handling system. We are constructing a compact accelerator-driven neutron source in the Nagoya University and confirm the practical reliability of the sealed lithium target for the BNCT application.
Poster Session and Reception / 71
Targets for the SPES project and its applications: material selec- tion and release simulations
Author: Michele Ballan1 Co-authors: Alberto Andrighetto 1; Alberto Monetti 1; Enrico Bagli 2; Francesca Borgna 1; Mattia Manzolaro 1; Stefano Corradetti 1
1 INFN-LNL 2 INFN-FE
Corresponding Author: [email protected]
The SPES (Selective Production of Exotic Species) ISOL facility at INFN-LNL will produce Radioactive Ion Beams (RIBs) by impinging a multi-foil uranium carbide target with a proton beam, accelerated up to 70 MeV by a cyclotron. The produced nuclei will be employed in many fields of research, ranging from astrophysics to material science and nuclear medicine. In order to increase the RIBs availability different target materials (i.e. SiC, TiC and ZrGe) are currently under investigation with Monte Carlo simulations using different codes for both isotopes production yield (FLUKA, GEANT4) and nuclear cross section studies (TALYS). Such materials were selected taking into account both the available proton beam energies and the expected working temperature (2000℃). In addition, the release from the target of the produced isotopes is under investigation through the definition of a new custom GEANT4 Monte Carlo model. Such a model is capable of simulating the nuclide diffusion and effusion processes, allowing the estimation of the mean release time for each produced specie. This work will include yield calculations for SiC, TiC, ZrGe and uranium carbide targets and a dedicated study of the nuclear cross section for the reaction natGe(p,X)64/67Cu, a promising alternative for the production of copper nuclides of medical interest. Regarding the custom GEANT4 model some preliminary numerical results will be shown. In particular, the release of rubidium isotopes from the uranium carbide target was simulated at different working temperatures.
Poster Session and Reception / 72
HiRadMat: A Unique Facility Testing Materials with High Power Pulsed Beam
Author: Fiona Harden1 Co-authors: Aymeric Bouvard 1; Nikolaos CHARITONIDIS 1; Yacine Kadi 1
1 CERN
Corresponding Author: [email protected]
The advancement of high power targets and accelerator components is dependent on the exploitation of irradiation facilities to assess these constituents for R&D purposes. HiRadMat (High Radiation to Materials) is an irradiation facility at CERN designed to provide material testing capabilities to a range of R&D projects using pulsed high energy, high intensity, proton and ion beams. Since its
Page 32 2018 High Power Targetry Workshop / Book of Abstracts
commissioning in 2011, HiRadMat has successfully delivered single pulsed proton beams to a multi- tude of novel experiments. The beam obtained directly from the TT60 line of the SPS, comparable to that extracted by the LHC, is at 440 GeV/c. A 1σ r.m.s. beam radius of 0.25 – 2 mm with a range of 1 to 288 protons per pulse at 1.2x10ˆ11 protons per bunch maximum (equivalent lead/argon ion beams available) can currently be delivered. Over 30 experiments have utilised this unique envi- ronment to test not only materials, but electronic devices, detectors and optical systems. Through Transnational Access support, currently under WP10 of ARIES, financial assistance can be provided to external users enabling an increase in the use of this irradiation facility by global institutes. The future strategy of HiRadMat is currently under examination. Facility consolidations, considering the increasing experimental demands from experiments and with the upgrade to High-Luminosity LHC with up to 2.3x10ˆ11 protons per bunch expected for LIU beams (LHC-Injector Upgrade), will be presented. Similarly, expansion into scientific areas beyond the accelerator physics community are to be discussed.
Session 5-Target Facility Challenges / 73
Design of high temperature ISOL targets
Author: Mattia Manzolaro1
Co-authors: Alberto Andrighetto 1; Alberto Monetti 1; Daniele Scarpa 1; Fabio D’Agostini 1; Francesca Borgna 1; Giovanni Meneghetti 2; Massimo Rossignoli 1; Michele Ballan 1; Stefano Corradetti 1
1 INFN-LNL 2 Università degli Studi di Padova
Corresponding Author: [email protected]
In the facilities for the production of radioactive ion beams based on the isotope separation on line (ISOL) technique, the target system is surely one of the most critical objects. Thick targets are widely used worldwide and they operate mainly in combination with high energy high intensity protons. High intensities are usually necessary to fulfill the most important target requirement, that isto produce as much isotopes as possible. In the specific case of the selective production of exotic species (SPES) facility, a uranium carbide target is impinged by a 40 MeV, 200 µA proton beam produced by a cyclotron proton driver. Under these conditions, a fission rate of approximately 10ˆ13 fissions per second is expected. Thetarget is composed of seven uranium carbide co-axial disks (closed inside a cylindrical graphite box), ap- propriately spaced in the axial direction in order to dissipate by thermal radiation the considerable amount of power deposited by the proton beam. The average working temperature is around 2000℃ with the aim to enhance both the diffusion and the effusion processes for the produced isotopes. So- phisticated heating systems were adopted to satisfy the aforementioned thermal specifications, and an integrated electrical-thermal-structural design was required to obtain a reliable target system for long term operation at high temperature. In the worldwide ISOL scenario other interesting and prestigious target architectures were devel- oped, and they are constantly updated and improved by dedicated working groups of physicists and engineers. In this work all the aforementioned points will be accurately described and commented, together with a general overview on new or recent developments for high power ISOL targets.
Poster Session and Reception / 74
Energy deposition in Candidate Materials for the Whole-Beam Dumps for the Advanced Photon Source Upgrade
Author: Jeff Dooling1
Co-authors: Bradley Micklich 2; Michael Borland 3
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1 Argonne National Laboratory/Advanced Photon Source 2 Argonne National Laboratory 3 Advanced Photon Source, Argonne National Laboratory
Corresponding Author: [email protected]
The APS-U will generate high-brightness x-rays using small, intense, 6-GeV electron beams with transverse dimensions of 0.010-0.015 mm, rms. Full beam aborts in the APS-U storage ring will sometimes be required for machine and personnel protection. These involve removing power from the accelerating cavities, which allows the beam to spiral in until it hits a whole beam dump (WBD). Simulations with MARS show that any solid material subject to a full beam abort (720 nC, 6 GeV) will be damaged and pushed into a hydrodynamic regime (>15 MGy). As a result, the WBD must be re-positioned after each full beam abort to expose new surface. Aside from choosing the appropriate material, an understanding of how the material behaves during the beam abort is required both for personnel and machine protection. A significant change to the WBD density during a beam abort will modify its ability to absorb energy during the later stages of the loss event. As examples, we evaluate the dose in four candidate materials: aluminum, titanium alloy, copper, and tungsten. We show that static simulations coupled with simple back-of-the-envelope calculations strongly suggest the generation of shocks in high-density, high-Z materials, likely making them unsuitable for the WBD. The need to couple a hydrodynamics code with the static dose simulation is discussed.
75 Design, study and tests of the Beam Dump for the SPES cyclotron commissioning
Author: Alberto Monetti1 Co-authors: Alberto Andrighetto 1; Aldo Zenoni 2; Antonietta Donzella 2; Augusto Lombardi 1; Carlo Roncolato 1; Daniela Benini 1; Daniele Scarpa 1; Davide Turcato 1; Enrico Boratto 1; Fabio D’Agostini 1; Flavio Pasquato 1; Francesca Borgna 1; Gianfranco Prete 1; Juan Esposito 1; Lorenzo Pranovi 1; Luca De Ruvo 1; Mario Maggiore 1; Massimo Rossignoli 1; Matteo Ferrari 2; Mattia Manzolaro 1; Michele Ballan 1; Piergiorgio Antonini 1; Stefano Corradetti 1
1 LNL-INFN 2 Università degli Studi di Brescia
Corresponding Author: [email protected]
The SPES project (Selective Production of Exotic Species) is a second-generation ISOL facility un- der construction at the LNL. The aim is the production of radioactive ion beams on the neutron rich side of the nuclide chart for nuclear structure and reaction studies, astrophysics research and interdisciplinary applications. The driver of the primary beam is a commercial cyclotron provided by BEST® Theratronics and installed during 2015. The commissioning of the cyclotron startedin 2016 sending the beam to a water cooled stationary beam dump in order to absorb the full beam power of 52.5 kW at 70 MeV. In this work, the design phase of the beam dump will be presented: starting from the input design data, which are beam shape and energy, thermo-mechanical analyses were performed in order to fulfil the requisites. In particular, the mechanical stresses and strains, caused by thermal expansion, turned out to be the most stringent requirements that could determine the beam dump failure. Then shields were implemented in order to reduce activation of theroom and doses for the future decommissioning phase. Finally, some experimental measures of the beam dump temperatures taken during the cyclotron commissioning will be presented.
76 Design Optimization of the Mu2e Production Target
Author: Kevin Lynch1
Page 34 2018 High Power Targetry Workshop / Book of Abstracts
1 York College/CUNY
Corresponding Author: [email protected]
Currently under construction at Fermilab, the Mu2e experiment will search for the neutrinoless coherent conversion of a muon to an electron in the field of an aluminum nucleus. Mu2e will produce its secondary beams using a radiation cooled tungsten primary target to intercept the 8 GeV, 7.3 kW proton beam from the Mu2e accelerator conference. We will present the design studies we have performed to understand muon yields and to optimize the design parameters of the target. We will also discuss simulation studies of possible future extensions to the Mu2e program - dubbed Mu2e-II - that could be performed with the PIP-II upgrades to the Fermilab complex.
77 Recent developments of Hot Isostatic Pressing diffusion bonding technologies to enhance cooling efficiency and reliability of pro- ton beam targets and dumps at CERN
Authors: Antonio Perillo-Marcone1; Josep Busom Descarrega1; Marco Calviani1
Co-authors: Ana Teresa Pérez Fontenla 1; Edmundo Lopez Sola 1; Stefano Sgobba 1; Thomas Schubert 2
1 CERN 2 Fraunhofer - IFAM
Corresponding Author: [email protected]
The LHC Injector Upgrade (LIU) project will imply higher intensity beams circulating intheCERN accelerator complex and therefore on the beam intercepting devices. Facilities concerning fixed- targets (e.g. AD, n_TOF) and dumps (e.g. SPS dump), which require several improvements, will be adapted to the new beam energies. In parallel, design and installation of new facilities is also fore- seen. New Beam Dump Facilities (BDF), a fixed-target/dump hybrid facility being studied at CERN, will also require dealing with large energy deposition. Evacuating the energy deposited by beams of such high intensity involves cooling with deminer- alized water at high pressure and velocity. Thus, excessive erosion corrosion might be induced on the target materials, that have to be protected with suitable claddings while insuring effective heat conductivity. The investigations carried out for two facilities are presented: a) for BDF, the application ofTabased claddings (1.5 mm thick) diffusion bonded to the target material to prevent erosion-corrosion and b) for the new SPS dump, the diffusion bonding between the Cu based cooling plate and embedded stainless steel cooling pipes. In both cases, high quality interfaces have only been achieved by means of Hot Isostatic Pressing (HIP) assisted diffusion bonding. Extensive studies have been carried out with the purpose of assessing the microstructural, mechan- ical and thermal properties of the different involved materials (W, Mo, Ta alloys for BDF; Cu alloys and stainless steels for SPS dump) after the HIP cycles, as well as of the relevant diffusion bonded interfaces. To this aim, prototypes at different scales were produced in order to investigate the influence of various HIP parameters and heat treatments on the microstructure of the differentma- terials involved and bonding quality. The effect of the addition of interlayer materials has alsobeen studied.
Session 8-Multipurpose Use of Targets and Beam Dumps / 78
High Power Liquid Lead-bismuth Targetry for Intense Fast Neu- tron Sources Using a Superconducting Electron Linac
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Author: Mayir Mamtimin1
1 Niowave Inc.
Niowave, in a close collaboration with the experts at LANL, is developing a forced-flow liquid metal based high power neutron target that can generate 1014 n/s source neutrons with a 40 MeV 50 kW electron beam. This neutron target not only drives Niowave’s subcritical uranium assembly forits medical isotope production facility, it also provides a fast-spectrum neutron environment for mate- rial irradiation studies for next generation reactor development. In this target, a high energy electron from Niowave’s superconducting electron linac generates bremsstrahlung in a high Z material then fission-like photoneutrons are produced via photonuclear reactions. Lead bismuth eutectic (LBE, Tmelt = 125 ℃) is chosen to efficiently convert electrons to neutrons and to dissipate heat when operating at high power since majority of beam power is deposited as heat in the target. Small quantities (few grams) of uranium can be added in LBE to increase neutron yield due to fission neutrons from photofission reaction. The system is equipped with an LBE mechanical pump, sealed LBE container, heat exchanger, and converter chamber where electron beam interacts with flowing LBE. Various sensors and instruments are being developed to monitor LBE temperature, flow rate, and oxygen content in this system. In parallel, Niowave de- signed and built a corrosion test station to investigate the corrosion behavior of various materials in high temperature LBE. Several samples (HT9, MA956, 304L, 316L, Ti, Ti alloy, Nb) were submerged in LBE for up to a month at a constant temperature ranging from 500 to 700 ℃. In this talk, we will present Niowave’s high power liquid metal target development activities includ- ing design, thermomechanical analysis, testing, concept validation, and future work. Versatility of the liquid metal target and its relevance to high power targetry development activities for nuclear physics research at FRIB will be discussed.
Session 4-Target Design, Analysis, Validation of Concepts / 79
High Power Capability of the Primary Beam Dump Drum for FRIB – Simulation and Experimental Study
Author: Mikhail Avilov1 Co-authors: Barrie Phillips 2; Frederique Pellemoine 2; Michael Schein 3; Wolfgang Mittig 4
1 FRIB Michigan State University 2 Michigan State University - Facility for Rare Isotope Beams 3 MSU-FRIB 4 MSU-NSCL
Corresponding Author: [email protected]
The Facility for Rare Isotope Beams (FRIB) is presently under construction at Michigan StateUni- versity. It is based on heavy ion accelerator which produces the primary ion beams from 16O to 238U with up to 400 kW power. For the rare isotope production the in-flight technique and frag- ment separation is used with over 300 kW of unreacted primary beam needing to be absorbed in the beam dump. The basic concept of the beam dump for FRIB assumes a rotating thin-wall drumfilled with water. Flowing water is used to both cool down the wall and stop the beam penetrating this 0.5 mm thick wall made of Ti-6Al-4V alloy. Under the extreme operational conditions the effects of high power density are significant and need detailed study, so the extensive thermal, mechanical and fluid flow analysis was performed taking into account the beam power deposited both inwater and drum wall. It appears that an intense water cooling is required to dissipate the power deposited in the wall, which for the heaviest 238U beam can reach 70 kW. The results of tests and simulations will be discussed in this paper. This material is based upon work supported by the U.S. Department of Energy Office ofScience under Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State Univer- sity.
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Session 2-Radiation Damage in Target Material and Related Simulations / 80
FRIB Radiation Studies: Damage, Component Lifetimes, Hands- on Accessibility
Author: Dali Georgobiani1
Co-authors: Georg Bollen 2; Mikhail Kostin 3
1 FRIB/MSU 2 Michigan State University 3 Facility for Rare Isotope Beams (FRIB), Michigan State University
Corresponding Author: [email protected]
The Facility for Rare Isotope Beams (FRIB), a project supported by the US DOE Office ofScience,is in the final stage of construction at Michigan State University. The project will use projectile frag- mentation and induced in-flight fission of heavy ion beams at energies of 200 MeV/u and higher, and at a beam power of up to 400 kW, to produce rare isotope beams for nuclear physics experiments. This work is focused on the target and beam dump modules located in the FRIB target hall. About 25% of the total beam power is absorbed by the target, creating high radiation environment. Another 75% of the beam is dissipated in the beam dump. We use radiologically bounding beams to estimate target graphite disk and titanium alloy beam dump drum radiation damage, and discuss their life- times. We calculate absorbed doses in target module and beam dump module parts and estimate component lifetimes. Radiation-tolerant materials will be used in the locations where high radia- tion occurs. We analyze hands-on accessibility to the top parts of the modules where utilities will be connected and disconnected. Further scenarios of the target module and beam dump evolution (removal, movement, repair, storage, and disposal) are briefly discussed. This material is based on work supported by the U.S. Department of Energy Office of Scienceunder Cooperative Agreement DE-SC0000661, the State of Michigan and Michigan State University. Michi- gan State University designs and establishes FRIB as a DOE Office of Science National User Facility in support of the mission of the Office of Nuclear Physics.
81 Conceptual design of the granular
Author: Yaling Zhang1
Co-authors: Lei Yang 2; Yanlin Li 3
1 Institute of Modern Physics, CAS 2 IMPCAS 3 No
The compact materials irradiation facility (CMIF) project aims at providing a compact high-energy & high-flux neutron source for fusion material research. Different from the International Fusion Materials Irradiation Facility (IFMIF), CMIF is a Be(d, xn) neutron source driven by a 10 mA @ 50 MeV continuous wave (CW) deuteron beam bombarding on a granular beryllium target. With a neutron flux of up to 10e19 m-2s-1, the irradiation damage of 10 60 dpa/fpy can be produced intest specimens. This paper presents the conceptual design of the CMIF target. The working mechanism and the stability of the granular flow target are investigated. The design of the key parameters ofthis facility including the beam spot as well as the corresponding neutron flux and irradiation damage level are performed. The heat deposition and transfer in the target are investigated numerically in detail. The operating requirements for the back plate are discussed.
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Session 4-Target Design, Analysis, Validation of Concepts / 82
Operation of and Upgrade Plans for the LANSCE Pulsed Neutron Sources
Author: Eric Pitcher1 Co-author: Michal Mocko 1
1 Los Alamos National Laboratory
The Los Alamos Neutron Science Center operates two pulsed neutron sources: the Lujan Centerand the Weapons Neutron Research (WNR) facility. Both are driven by 800-MeV LANSCE proton linear accelerator. The Lujan Center delivers moderated neutrons to seven flight paths serving both nuclear science and materials science applications, while the unmoderated neutron source at WNR serves six flight paths measuring nuclear data, electronics effects testing, and fast neutron radiography. The Lujan Center target-moderator-reflector-shield (TMRS) system was last replaced in 2010with the so-called Mark III target, and is due to be replaced in 2020 with a Mark IV target. This replace- ment provides an opportunity to optimize the TMRS design to the evolving missions that the Lujan Center serves. The Mark IV target design takes advantage of the Lujan Center’s two-tiered designto optimize the lower tier for cold and thermal neutron beams serving materials science instruments, and the upper tier for epithermal neutron beams serving nuclear science instruments. The Mark III target installed in 2010 was the first Lujan Center target to employ claddingaround the tungsten, which is resulted in drastic reductions in radiation levels in the water cooling sys- tem. In 2014, the WNR target was inadvertently operated without active water cooling, resulting in target overheating. A follow-on management assessment of this incident determined that the flow sensor that was tied to the Run Permit system did not indicate a fault condition due to improper design.
Session 7-Operation of Targets and Beam Dumps / 86
Radiation Protection at CERN - learn from the past and prepare for the future
Author: Heinz Vincke1
1 CERN
Corresponding Author: [email protected]
CERN is one of the world-leading laboratories for particle physics and was founded more than 60 years ago. The 600 MeV Synchrocyclotron (SC), built in 1957, was CERN’s first accelerator that provided beams for CERN’s first experiments in particle and nuclear physics. Since then several more powerful, more intense and also much larger accelerators have been built like the Large Hadron collider (LHC) which has started operation in 2008. Protection of people from ionising radiation as well as of the environment has always been a very important task of the Radiation Protection Group at CERN. This goes together with more restrictive radiation protection limits nowadays compared to the ones in force during the operation of CERNs first accelerators and even compared to the limits at the end of the last century. This talk will give an overview of the tasks and developments inthe RP group at CERN and will also address the challenges ahead of us in the future.
Session 8-Multipurpose Use of Targets and Beam Dumps / 87
Isotope Harvesting at FRIB
Page 38 2018 High Power Targetry Workshop / Book of Abstracts
Author: Gregory Severin1
1 Facility for Rare Isotope Beams
Inside the high-power beamstop at FRIB, nuclear reactions between the fast heavy-ion beam and water will create a large number of by-product radionuclides. Many of them are valuable for ap- plied and basic-science research if they can be efficiently recovered from the beamstop water. We are currently designing and testing the systems that will allow collection and purification of these radionuclides, and one major concern is that many of the envisioned processes will be influenced by the unique radiolysis environment inside of the cooling system. Varied redox potentials and a pulsed time-dependent pH in the cooling water will potentially lead to unpredictable speciation of aqueous ions and the inclusion of corrosion products. Meanwhile the sensitivity of the cooling sys- tem to chemical alterations precludes intervention, except to maintain the physical integrity of the cooling system components. Despite the challenges, preliminary testing at the NSCL shows that harvesting is feasible and is an important path towards obtaining the unique radionuclides created by heavy-ion interactions with water.
91 Welcome Talk
92 High Power Targetry at FRIB
Corresponding Author: [email protected]
93 Targets for the SPES project and its applications: material selec- tion and release simulations
Author: Michele Ballan1
1 INFN-LNL
Corresponding Author: [email protected]
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