ICANS XXI Dawn of High Power Neutron Sources and Science Applications
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A Search for Free Oscillations at the ESS N
A search for free n → n oscillations at t he ESS π π ? n n π π π D. Milstead Stockholm University Why baryon number violation ? Why baryon number violation ? • Baryon number is not a ”sacred” quantum number – Approximate conservation of BN in SM • ”Accidental” global symmetry at perturbative level – Depends on specific matter content of the SM • BNV in SM by non-perturbative processes –Sphalerons – B-L conserved in SM, not B,L separately. – Generic BNV in BSM theories, eg, SUSY. – BNV a Sakharov condition for baryogenesis Why n→ n ? n→ n • Theory • Baryogenesis via BNV (Sakharov condition) • SM extensions from TeV mass scales scale-upwards • Complementarity with open questions in neutrino physics • Experiment • One of the few means of looking for pure BNV • Stringent limit on stability of matter Neutron oscillations – models • Back-of-envelope dimensional reasoning: cΛ6 6 q operator for ∆B =2, ∆ L = 0⇒ δ m= QCD ⇒ M ∼ 1000 TeV n→ n M 5 • R-parity violating supersymmetry • Unification models: M ∼ 1015 GeV • Extra dimensions models • Post-sp haleron baryogenesis • etc, etc: []arXiv:1410.1100 High precision n→ n search ⇒ Scan over wide range of phase space for generic BNV + ⇒ model constai nts. Extend sensitivity in RPV-SUSY ATLAS multijet ATLAS CMS dijet CMS ESS Arxiv:1602.04821 (hep-ph) Displaced jets RPV-SUSY – TeV-scale sensitivity Neutrino physics ⇔ neutron oscillations Neutrinoless 2β -decay n→ n Eg seesaw mechanism for light ν Eg Unification models ∆L =2, ∆ B = 0, ∆L =0, ∆ B = 2, 2 ∆()B − L = 2 ∆()B − L = Neutrinoless 2β -decay ⇔ nn → linked under BL - viol ation. -
Three Dimensional Polarimetric Neutron Tomography of Magnetic
www.nature.com/scientificreports OPEN Three Dimensional Polarimetric Neutron Tomography of Magnetic Fields Received: 25 April 2017 Morten Sales 1, Markus Strobl 2,3, Takenao Shinohara4, Anton Tremsin5, Luise Theil Kuhn 6, Accepted: 18 January 2018 William R. B. Lionheart7, Naeem M. Desai 7, Anders Bjorholm Dahl8 & Søren Schmidt 1 Published: xx xx xxxx Through the use of Time-of-Flight Three Dimensional Polarimetric Neutron Tomography (ToF 3DPNT) we have for the frst time successfully demonstrated a technique capable of measuring and reconstructing three dimensional magnetic feld strengths and directions unobtrusively and non- destructively with the potential to probe the interior of bulk samples which is not amenable otherwise. Using a pioneering polarimetric set-up for ToF neutron instrumentation in combination with a newly developed tailored reconstruction algorithm, the magnetic feld generated by a current carrying solenoid has been measured and reconstructed, thereby providing the proof-of-principle of a technique able to reveal hitherto unobtainable information on the magnetic felds in the bulk of materials and devices, due to a high degree of penetration into many materials, including metals, and the sensitivity of neutron polarisation to magnetic felds. The technique puts the potential of the ToF time structure of pulsed neutron sources to full use in order to optimise the recorded information quality and reduce measurement time. Te spin of a neutron passing through a magnetic feld will undergo an amount of precession proportional to the strength of the magnetic feld and the time spent by the neutron in the magnetic feld. Te time is proportional to the neutron wavelength, λ, and the path length through the magnetic feld, L. -
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Φ()Edeat∆≡ Nedeavt () [ ∆ ] (2)
22.54 Neutron Interactions and Applications (Spring 2002) Lecture Notes on Neutronics of Multiplying Media This is a set of notes for the four lectures on neutron interactions in a reactor system in which a neutron population can change as a result of capture and fission reactions, in addition to scattering. We will discuss the concept of criticality as a way of describing any self-sustaining chain reaction which, in principle, can be just as well chemical in nature, and focus on the fundamental understanding of neutron diffusion and slowing down, and the interplay between materials constants (expressed through cross sections) and geometric factors (system size and shape) in determining criticality. The four lectures are: Lec 14. Neutronics of Multiplying Media – criticality, moderation, leakage Lec 15. Elements of Neutron Diffusion Theory Lec 16. Neutron Slowing Down Lec.17. The Two-Group Two-Region Reactor As a start the following references are recommended for supplemental reading: J. Lemarsh, Introduction to Nuclear Reactor Theory K. M. Case, F. deHoffmann, G. Placzek, Introduction to The Theory of Neutron Diffusion, vol. 1, LASL, 1953. I. Some Basic Notions of Neutron Multiplication Consider a homogeneous beam of neutrons having a distribution of energies. Define distribution function n(E) such that n(E)dE = expected no, of neutrons with energies in dE about E per cm3 (1) Suppose we ask how many neutrons in a certain energy range will cross an area during a time interval ∆t. Call this number φ()EdEAt∆≡ nEdEAvt () [ ∆ ] (2) since all the neutrons in a certain volume Av ∆t will cross during ∆t. -
Application of 3D Neutron Imaging and Tomography in Cultural Heritage Research
F1-RC-1219.1 LIMITED DISTRIBUTION International Atomic Energy Agency Coordinated Research Project on Application of 3D Neutron Imaging and Tomography in Cultural Heritage Research Report of the first Research Co-ordination Meeting Vienna, Austria 07 - 11 May 2012 Reproduced by the IAEA Vienna, Austria, 2012 NOTE The material reproduced here has been supplied by the authors and has not been edited by the IAEA. The views expressed remain the responsibility of the named authors and do not necessarily reflect those of the government(s) of the designating Member State(s). In particular, neither the IAEA nor any other organization or body sponsoring the meeting can be held responsible for this material CONTENTS 1. FOREWORD .................................................................................................................... 1 2. EXECUTIVE SUMMARY ............................................................................................... 2 3. INTRODUCTION ............................................................................................................. 3 4. CRP OBJECTIVES ........................................................................................................... 4 4.1. Objectives of the CRP ............................................................................................ 4 4.2. Objectives of 1st RCM meeting ............................................................................. 4 4.3 Working groups: .................................................................................................... -
Conceptual Design Report Jülich High
General Allgemeines ual Design Report ual Design Report Concept Jülich High Brilliance Neutron Source Source Jülich High Brilliance Neutron 8 Conceptual Design Report Jülich High Brilliance Neutron Source (HBS) T. Brückel, T. Gutberlet (Eds.) J. Baggemann, S. Böhm, P. Doege, J. Fenske, M. Feygenson, A. Glavic, O. Holderer, S. Jaksch, M. Jentschel, S. Kleefisch, H. Kleines, J. Li, K. Lieutenant,P . Mastinu, E. Mauerhofer, O. Meusel, S. Pasini, H. Podlech, M. Rimmler, U. Rücker, T. Schrader, W. Schweika, M. Strobl, E. Vezhlev, J. Voigt, P. Zakalek, O. Zimmer Allgemeines / General Allgemeines / General Band / Volume 8 Band / Volume 8 ISBN 978-3-95806-501-7 ISBN 978-3-95806-501-7 T. Brückel, T. Gutberlet (Eds.) Gutberlet T. Brückel, T. Jülich High Brilliance Neutron Source (HBS) 1 100 mA proton ion source 2 70 MeV linear accelerator 5 3 Proton beam multiplexer system 5 4 Individual neutron target stations 4 5 Various instruments in the experimental halls 3 5 4 2 1 5 5 5 5 4 3 5 4 5 5 Schriften des Forschungszentrums Jülich Reihe Allgemeines / General Band / Volume 8 CONTENT I. Executive summary 7 II. Foreword 11 III. Rationale 13 1. Neutron provision 13 1.1 Reactor based fission neutron sources 14 1.2 Spallation neutron sources 15 1.3 Accelerator driven neutron sources 15 2. Neutron landscape 16 3. Baseline design 18 3.1 Comparison to existing sources 19 IV. Science case 21 1. Chemistry 24 2. Geoscience 25 3. Environment 26 4. Engineering 27 5. Information and quantum technologies 28 6. Nanotechnology 29 7. Energy technology 30 8. -
THE SPALLATION NEUTRON SOURCE (SNS) PROJECT Jose Alonso
THE SPALLATION NEUTRON SOURCE (SNS) PROJECT Jose Alonso The SNS is currently the US Department of Energy's activation and residual-radiation levels in the tunnels are largest accelerator construction project, and is being low enough to allow quick access and hands-on carried out by a partnership of five DOE National maintenance, and is driven by the very high reliability and Laboratories for building the world's most powerful availability specifications associated with the strong user- accelerator-based pulse spallation source. At its planned orientation of the SNS facility. Areas where unusable 2 MW operating level, it will produce neutron fluxes at beam is diverted (so-called "controlled" beam-loss least a factor of ten greater than Rutherford Appleton points), such as collimators, scrapers and dumps, must be Laboratory’s ISIS, currently the world’s leading spallation designed to collect these particles in a way that contribute source. The current design of the SNS, shown in Figure only minimally to background levels in the tunnels where 1, calls for a full-energy (1 GeV) linac delivering 1 ms access is required. Normal loss mechanisms must receive pulses to an Accumulator Ring which compresses these particular attention to meet this specification. This into 600 ns proton pulses that strike a liquid mercury implies very tight control over beam emittance, and target at a 60 Hz rate. Room-temperature and cryogenic emittance growth; designing for the largest-possible stay- moderators produce beams of slow neutrons suitable for clear apertures in linac, transport and ring structures; materials research with an initial suite of at least 10 understanding of space-charge and halo effects in linac and ring; ensuring highest-possible vacuum in areas neutron-scattering instruments. -
The HIBEAM Experiment for the European Spallation Source
The HIBEAM Experiment for the European Spallation Source n ? n D. Milstead Stockholm University Outline 1. The aims of the experiment 2. The physics case 3. The proposed program at the ESS 4. Status HIBEAM High Intensity Baryon Extraction and Measurement Search for • 푛 → 푛ത • 푛 → 푛′ (mirror neutrons) Also measurements of weak nucleon-nucleon interactions. Baryon and lepton number violation • BN,LN ”accidental” SM symmetries at perturbative level – BNV, LNV in SM non-perturbatively (eg instantons) – B-L is conserved, not B, L separately. • BNV, LNV needed for baryogenesis and leptogenesis • BNV,LNV generic features of SM extensions (eg SUSY) nn Dimensional reasoning: c6 6q operator for B 2, L 0 m QCD M 1000 TeV nn M 5 R-parity violating supersymmetry Unification theories: M 1015 GeV Extra dimensions models Post-sphaleron baryogenesis etc, etc: arXiv:1410.1100 High precision n n search Scan over wide range of phase space for generic BNV + model constaints. RPV-SUSY Super-K ILL LHC, flavour Constraints vanish for >> TeV masses nnbar@ESS: extends mass range by up to ~400 TeV cf Super-K : pushes into the PeV scale Complementary B,L-violation observables BL 1, BL 2, 0, BL 0, 2, BL 0 BL 2 BL 2 Symbiosis n n , NN decay. Nucleon decay Stable proton. 0 Few pure BNV searches Neutron oscillations – an experimentalist’s view Hypothesis: baryon number is weakly violated. How do we look for BNV? Single nucleon decay searches, eg, pe 0 ? L-violation, another (likely weakly) violated quantity. Decays without leptons, eg, p , impossible due to angular momentum conservation. -
Instrumental Aspects
EPJ Web of Conferences 155, 00002 (2017) DOI: 10.1051/epjconf/201715500002 JDN 22 Instrumental aspects Navid Qureshi Institut Laue Langevin, 38000 Grenoble, France Abstract. Every neutron scattering experiment requires the choice of a suited neutron diffractometer (or spectrometer in the case of inelastic scattering) with its optimal configuration in order to accomplish the experimental tasks in the most successful way. Most generally, the compromise between the incident neutron flux and the instrumental resolution has to be considered, which is depending on a number of optical devices which are positioned in the neutron beam path. In this chapter the basic instrumental principles of neutron diffraction will be explained. Examples of different types of experiments and their respective expectable results will be shown. Furthermore, the production and use of polarized neutrons will be stressed. 1. Introduction A successful neutron scattering experiment requires a thorough plan of which instrument to use and how to set up its configuration in order to obtain the best possible results. Optimally, the decision of the set-up is taken beforehand, but in many cases the instrument parameters are modified on-the-fly after analyzing the first results. Due to the different experimental tasks – reaching from magnetic or nuclear structure investigation to the mapping of phase diagrams – and the different sample dimensions (both the crystal size and the lattice parameters), which can be investigated at one and the same instrument, it becomes obvious that the versatility of some instruments has to be adjusted to satisfy the experimental tasks. Obviously, the sample state (powder, single crystal, liquid, etc.) limits the choice of instruments, however, you can find powder diffractometers which differ from each other concerning the used neutron wavelength and particular devices in the beam path in order to maximize the efficiency for a type of experiment. -
Small Angle Scattering in Neutron Imaging—A Review
Journal of Imaging Review Small Angle Scattering in Neutron Imaging—A Review Markus Strobl 1,2,*,†, Ralph P. Harti 1,†, Christian Grünzweig 1,†, Robin Woracek 3,† and Jeroen Plomp 4,† 1 Paul Scherrer Institut, PSI Aarebrücke, 5232 Villigen, Switzerland; [email protected] (R.P.H.); [email protected] (C.G.) 2 Niels Bohr Institute, University of Copenhagen, Copenhagen 1165, Denmark 3 European Spallation Source ERIC, 225 92 Lund, Sweden; [email protected] 4 Department of Radiation Science and Technology, Technical University Delft, 2628 Delft, The Netherlands; [email protected] * Correspondence: [email protected]; Tel.: +41-56-310-5941 † These authors contributed equally to this work. Received: 6 November 2017; Accepted: 8 December 2017; Published: 13 December 2017 Abstract: Conventional neutron imaging utilizes the beam attenuation caused by scattering and absorption through the materials constituting an object in order to investigate its macroscopic inner structure. Small angle scattering has basically no impact on such images under the geometrical conditions applied. Nevertheless, in recent years different experimental methods have been developed in neutron imaging, which enable to not only generate contrast based on neutrons scattered to very small angles, but to map and quantify small angle scattering with the spatial resolution of neutron imaging. This enables neutron imaging to access length scales which are not directly resolved in real space and to investigate bulk structures and processes spanning multiple length scales from centimeters to tens of nanometers. Keywords: neutron imaging; neutron scattering; small angle scattering; dark-field imaging 1. Introduction The largest and maybe also broadest length scales that are probed with neutrons are the domains of small angle neutron scattering (SANS) and imaging. -
Use of Neutron Beams for Low and Medium Flux Research Reactors: Radiography and Materials Characterization
IAEA-TECDOC-837 Use of neutron beams for low and medium flux research reactors: radiography and materials characterization Report Technicala of Committee meeting held in Vienna, 4-7 May 1993 INTERNATIONAL ATOMIC ENERGY AGENCY The originating Sectio f thino s publicatio IAEe th An i was: Physics Section International Atomic Energy Agency Wagramerstrasse 5 0 10 x P.OBo . A-1400 Vienna, Austria USE OF NEUTRON BEAMS FOR LOW AND MEDIUM FLUX RESEARCH REACTORS: RADIOGRAPH MATERIALD YAN S CHARACTERIZATION IAEA, VIENNA, 1995 IAEA-TECDOC-837 ISSN 1011-4289 ©IAEA, 1995 Printe IAEe th AustriAn i y d b a October 1995 FOREWORD Research reactors have been playing an important role in the development of scientific and technological infrastructure and in training of manpower for the introduction of nuclear power in many countries. Currently, there are 284 operational research reactors in the world, includindevelopin9 3 n i 8 g8 g countries numbee th ; f reactoro r developinn si g countries si increasin s morga e countries embar programmen ko nuclean i s r scienc technologyd ean . However, full utilization of these facilities for fundamental and applied research has seldom been achieved. In particular, the utilization of beam ports has been quite low. Neutron beam based researce mosth f t o s regardeimportani he on s a d t research programme carriee sb than dca t out, eve mediud nan witw mhlo flux reactors range Th .f eo activities possibl n thii e s wido s fiel s e i d s generall i tha t i t y feasibl o defint D e R& e programmes suite specifio dt c need conditionsd san therefors i t I . -
Viii-I. Summary of Research Activities
VIII-I. SUMMARY OF RESEARCH ACTIVITIES VIII-I-1. MEETINGS AND SEMINARS Specialists’ Meetings Held in the FY 2013 1. Issues in Radiogenic Circulatory Disease and Cataracts 2. Proceedings of Workshop on Reactor Physics 3. The Results and Future Prospects of Activation Analysis Using KUR" 4. Workshop on Materials Irradiation Effects and Applications 5. Proceedings of the Specialist Research Meeting on Science and Engineering of Unstable Nuclei and Their Uses on Condensed Matter Physics III 6. Proceedings of the Specialist Research Meeting on “Abnormal Protein Aggregation and the Folding Diseases, and their Protection and Repair System” (VI) 7. Proceedings of the Symposium on Present and Future Statuses of Criticality Safety Research 8. Novel Development of BNCT - From Special to General - 9. Proceedings of the Specialists' Meeting on the Chemistry and Technology of Actinide Elements Proceedings of the Specialist Research Meeting on Science and Engineering of Unstable Nuclei and Their 10. Technological Development, Operation, and Data Analysis of Radiation Mapping Systems in Affected Area of Nuclear Accident 11. Proceedings of the Specialist Meeting on Positron Annihilation Study for Science and Engineering 2013 12. Proceedings of the Specialists' Meeting on Radioactive Wastes Management 13. Neutron Imaging Workshops Organized in the FY 2013 1. Promotion of Leading Research toward Effective Utilization of Multidisciplinary Nuclear Science and Technology 2. Workshop of Next Neutron Source for Beam Utilization after KUR II Special Meeting Held in the FY2013 Meeting on the Future Project of the Kyoto University Research Reactor Institute VIII-I-2. COLLABORATION RESEARCH AND VISITING SCIENTISTS Visiting Scientists The number of project researches .................................................. 11 (The number of allotted research subject) ............................... -
Nist Center for Neutron Research Accomplishments and Opportunities
RXC NATL INST. OF STAND & TECH WIST PUBLICATIONS A111QS 6=11773- m ON THE COVER Part of the 913-detector array of the new Disk Chopper Spectrometer (DCS) that will be available to users in 2000. To view the detectors as found in the instrument, the picture should be rotated 90°. Information about the DCS and other instruments at NCNR is available at http://www.ncnr.nist.gov/. Photo: Mark Heifer NCNR 1999 NIST CENTER FOR NEUTRON RESEARCH ACCOMPLISHMENTS AND OPPORTUNITIES NIST Special Publication 944 J. Michael Rowe, Director Ronald L. Cappelletti, Editor Linda K. Clutter, Assistant Editor January 2000 U.S. DEPARTMENT OF COMMERCE William M. Daley, Secretary Technology Administration Dr. Cheryl L. Shavers, Under Secretary of Commerce for Technology National Institute of Standards and Technology Raymond G. Kammer, Director DISCLAIMER Certain commercial equipment, instruments, or materials are identified in this report to foster understanding. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose. National Institute of Standards and Technology Special Publication 944 Natl. Inst. Stand. Technol. Spec. Publ. 944, 80 pages (January 2000) CODEN: NSPUE2 U.S. GOVERNMENT PRINTING OFFICE - WASHINGTON: 2000 For Sale by the Superintendent of Documents, U.S. Government Printing Office Washington, DC 20402-9325 CONTENTS Foreword iv Introduction to the NIST Center for Neutron Research