The Neutron Cross Section Standards, Evaluations and Applications
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Neutron Interactions and Dosimetry Outline Introduction Tissue
Outline • Neutron dosimetry Neutron Interactions and – Thermal neutrons Dosimetry – Intermediate-energy neutrons – Fast neutrons Chapter 16 • Sources of neutrons • Mixed field dosimetry, paired dosimeters F.A. Attix, Introduction to Radiological • Rem meters Physics and Radiation Dosimetry Introduction Tissue composition • Consider neutron interactions with the majority tissue elements H, O, C, and N, and the resulting absorbed dose • Because of the short ranges of the secondary charged particles that are produced in such interactions, CPE is usually well approximated • Since no bremsstrahlung x-rays are generated, the • The ICRU composition for muscle has been assumed in absorbed dose can be assumed to be equal to the most cases for neutron-dose calculations, lumping the kerma at any point in neutron fields at least up to 1.1% of “other” minor elements together with oxygen to an energy E ~ 20 MeV make a simple four-element (H, O, C, N) composition Neutron kinetic energy Neutron kinetic energy • Neutron fields are divided into three • Thermal neutrons, by definition, have the most probable categories based on their kinetic energy: kinetic energy E=kT=0.025eV at T=20C – Thermal (E<0.5 eV) • Neutrons up to 0.5eV are considered “thermal” due to simplicity of experimental test after they emerge from – Intermediate-energy (0.5 eV<E<10 keV) moderator material – Fast (E>10 keV) • Cadmium ratio test: • Differ by their primary interactions in tissue – Gold foil can be activated through 197Au(n,)198Au interaction and resulting biological effects -
Neutron Activation System for Spectral Measurements of Pulsed Ion Diode Neutron Production
Q-,? \^ <A \ SAND79-2196 Unlimited Rtlciie UC-37 #^ Neutron Activation System for Spectral Measurements of Pulsed Ion Diode Neutron Production Dwid L. Hanton, Ly(# W. Kniw 1 I. Introduction The ability to characterize neutron energy spectra is essential for the application of intense pulsed neutron sources to radiation effects simulation and fusion materials damage studies. However, the problems of neutron detection are par ticularly severe in the environment of relativistic electron beam (REB) accelerators where intense electromagnetic and bremsstrahlung x-ray pulses are generated. A system for de tecting neutrons in such a harsh radiation environment has been developed for use with Sandia's pulsed accelerators and is described in a previous report. The essential components of this system are: (1) total neutron yield detectors (Ag activation 2 counters) to determine the total number of neutrons from a pulse; (2) a fast response time, high efficiency time-of- flight (TOF) spectrometer, consisting of a shielded liquid scintillator and gated photo- multiplier of special design, to characterize the time distribution and approximate energy spectrum of the neutrons; and (3) a neutron activation system to accurately de termine the neutron energy spectrum. This integrated diagnostic system is able to provide a complete picture of the time and energy di s*-ribution of neutrons produced in a REB diode shot. However, the neutron activation system of Ref. 1 made use a Nal(Tlj well crystal 5 to detect residual activity and was severely limited in its effectiveness by coincidence sum effects. The purpose of the present report is to describe the design of a much improved neutron activation system and its application as a neutron spectrometer in a recent series of Hermes II neutron produc tion experiments. -
MASTER 9700 South Cass Avenue Argonne, Illinois 60439 USA
ANL/KDH—SO DE84 001440 ANL/NDM-80 NEUTRON TOTAL CROSS SECTION MEASUREMENTS IN THE ENERGY REGION FROM 47 key to 20 MeV* by W. P. Poenitz and J. F. Whalon Applied Physics Division May, 1983 *This work supported by the U.S. Department of Energy Argonne National Laboratory MASTER 9700 South Cass Avenue Argonne, Illinois 60439 USA fflSTRtBtfUOU OF miS DOCUMENT IS UNLIMITED NUCLEAR DATA AMD MEASUREMENTS SERIES The Nuclear Data and Measurements Series presents results of studies in the field of microscopic nuclear data. The primary objective is the dissemination of information in the comprehensive form required for nuclear technology applications. This Series is devoted to: a) measured microscopic nuclear parameters, b) experimental techniques and facilities employed in measurements, c) the analysis, correlation and interpretation of nuclear data, and d) the evaluation of nuclear data. Contributions to this Series are reviewed to assure technical competence and, unless otherwise stated, the contents can be formally referenced. This Series does not supplant formal journal publication but it does provide the more extensive informa- tion required for technological applications (e.g., tabulated numerical data) in a timely manner. DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or retpoosi- bility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Refer- ence herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recom- mendation, or favoring by the United States Government or any agency thereof. -
Neutron-Induced Fission Cross Section of 240,242Pu up to En = 3 Mev
Neutron-induced fission cross section of 240;242Pu Paula Salvador-Castineira~ Supervisors: Dr. Franz-Josef Hambsch Dr. Carme Pretel Doctoral dissertation PhD in Nuclear Engineering and Ionizing Radiation Barcelona, September 2014 Curs acadèmic: Acta de qualificació de tesi doctoral Nom i cognoms Programa de doctorat Unitat estructural responsable del programa Resolució del Tribunal Reunit el Tribunal designat a l'efecte, el doctorand / la doctoranda exposa el tema de la seva tesi doctoral titulada __________________________________________________________________________________________ _________________________________________________________________________________________. Acabada la lectura i després de donar resposta a les qüestions formulades pels membres titulars del tribunal, aquest atorga la qualificació: NO APTE APROVAT NOTABLE EXCEL·LENT (Nom, cognoms i signatura) (Nom, cognoms i signatura) President/a Secretari/ària (Nom, cognoms i signatura) (Nom, cognoms i signatura) (Nom, cognoms i signatura) Vocal Vocal Vocal ______________________, _______ d'/de __________________ de _______________ El resultat de l’escrutini dels vots emesos pels membres titulars del tribunal, efectuat per l’Escola de Doctorat, a instància de la Comissió de Doctorat de la UPC, atorga la MENCIÓ CUM LAUDE: SÍ NO (Nom, cognoms i signatura) (Nom, cognoms i signatura) President de la Comissió Permanent de l’Escola de Doctorat Secretària de la Comissió Permanent de l’Escola de Doctorat Barcelona, _______ d'/de ____________________ de _________ Universitat Politecnica` -
Neutron Activation and Prompt Gamma Intensity in Ar/CO $ {2} $-Filled Neutron Detectors at the European Spallation Source
Neutron activation and prompt gamma intensity in Ar/CO2-filled neutron detectors at the European Spallation Source E. Diana,b,c,∗, K. Kanakib, R. J. Hall-Wiltonb,d, P. Zagyvaia,c, Sz. Czifrusc aHungarian Academy of Sciences, Centre for Energy Research, 1525 Budapest 114., P.O. Box 49., Hungary bEuropean Spallation Source ESS ERIC, P.O Box 176, SE-221 00 Lund, Sweden cBudapest University of Technology and Economics, Institute of Nuclear Techniques, 1111 Budapest, M}uegyetem rakpart 9. dMid-Sweden University, SE-851 70 Sundsvall, Sweden Abstract Monte Carlo simulations using MCNP6.1 were performed to study the effect of neutron activation in Ar/CO2 neutron detector counting gas. A general MCNP model was built and validated with simple analytical calculations. Simulations and calculations agree that only the 40Ar activation can have a considerable effect. It was shown that neither the prompt gamma intensity from the 40Ar neutron capture nor the produced 41Ar activity have an impact in terms of gamma dose rate around the detector and background level. Keywords: ESS, neutron detector, B4C, neutron activation, 41Ar, MCNP, Monte Carlo simulation 1. Introduction Ar/CO2 is a widely applied detector counting gas, with long history in ra- diation detection. Nowadays, the application of Ar/CO2-filled detectors is ex- tended in the field of neutron detection as well. However, the exposure of arXiv:1701.08117v2 [physics.ins-det] 16 Jun 2017 Ar/CO2 counting gas to neutron radiation carries the risk of neutron activa- tion. Therefore, detailed consideration of the effect and amount of neutron ∗Corresponding author Email address: [email protected] (E. -
An Exploration of Neutron Detection in Semiconducting Boron Carbide
University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Theses, Dissertations, and Student Research: Department of Physics and Astronomy Physics and Astronomy, Department of 4-2012 An Exploration of Neutron Detection in Semiconducting Boron Carbide Nina Hong University of Nebraska-Lincoln, [email protected] Follow this and additional works at: https://digitalcommons.unl.edu/physicsdiss Part of the Physics Commons Hong, Nina, "An Exploration of Neutron Detection in Semiconducting Boron Carbide" (2012). Theses, Dissertations, and Student Research: Department of Physics and Astronomy. 20. https://digitalcommons.unl.edu/physicsdiss/20 This Article is brought to you for free and open access by the Physics and Astronomy, Department of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Theses, Dissertations, and Student Research: Department of Physics and Astronomy by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. An Exploration of Neutron Detection in Semiconducting Boron Carbide by Nina Hong A DISSERTATION Presented to the Faculty of The Graduate College of the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Doctor of Philosophy Major: Physics & Astronomy Under the Supervision of Professor Shireen Adenwalla Lincoln, Nebraska April, 2012 An Exploration of Neutron Detection in Semiconducting Boron Carbide Nina Hong, Ph.D. University of Nebraska, 2012 Advisor: Shireen Adenwalla The 3He supply problem in the U.S. has necessitated the search for alternatives for neutron detection. The neutron detection efficiency is a function of density, atomic composition, neutron absorption cross section, and thickness of the neutron capture material. The isotope 10B is one of only a handful of isotopes with a high neutron absorption cross section—3840 barns for thermal neutrons. -
Concrete Analysis by Neutron-Capture Gamma Rays Using Californium 252
CONCRETE ANALYSIS BY NEUTRON-CAPTURE GAMMA RAYS USING CALIFORNIUM 252 Dick Duffey, College of Engineering, University of Maryland; Peter F. Wiggins, Naval Systems Engineering Department, U.S. Naval Academy; Frank E. Senftle, U.S. Geological Survey; and A. A. El Kady, United Arab Republic Atomic Energy Establishment, Cairo The feasibility of analyzing concrete and cement by a measurement of the neutron-capture or prompt gamma rays was investigated; a 100-ug californium-252 source was used to supply the neutrons. A lithium drifted germanium crystal detected the capture gamma rays emitted. The capture gamma rays from cement, sand, and 3 coarse aggregates-quartzite gravel, limestone, and diabase--:were studied. Concrete blocks made from these materials were then tested. The capture gamma ray response of the calcium, silicon, and iron in the concrete blocks was in accord with the elements identified in the mix materials. The principal spectral lines used were the 6.42 MeV line of calcium, the 4.93 MeV line of silicon, and the doublet of iron at about 7 .64 MeV. The aluminum line at 7. 72 MeV was ob served in some cases but at a lower intensity with the limited electronic equipment available. This nuclear spectroscopic technique offers a possi ble method of determining the components of sizable concrete samples in a nondestructive, in situ manner. In addition, the neutron-capture gamma ray technique might find application in control of the concrete and cement processes and furnish needed information on production operations and inventories. • FROM THE point of view of the geochemical analyst, concrete may be considered as rock relocated and reformed at the convenience of the engineer. -
Uses of Isotopic Neutron Sources in Elemental Analysis Applications
EG0600081 3rd Conference on Nuclear & Particle Physics (NUPPAC 01) 20 - 24 Oct., 2001 Cairo, Egypt USES OF ISOTOPIC NEUTRON SOURCES IN ELEMENTAL ANALYSIS APPLICATIONS A. M. Hassan Department of Reactor Physics Reactors Division, Nuclear Research Centre, Atomic Energy Authority. Cairo-Egypt. ABSTRACT The extensive development and applications on the uses of isotopic neutron in the field of elemental analysis of complex samples are largely occurred within the past 30 years. Such sources are used extensively to measure instantaneously, simultaneously and nondestruclively, the major, minor and trace elements in different materials. The low residual activity, bulk sample analysis and high accuracy for short lived elements are improved. Also, the portable isotopic neutron sources, offer a wide range of industrial and field applications. In this talk, a review on the theoretical basis and design considerations of different facilities using several isotopic neutron sources for elemental analysis of different materials is given. INTRODUCTION In principle there are two ways to use neutrons for elemental and isotopic abundance analysis in samples. One is the neutron activation analysis which we call it the "off-line" where the neutron - induced radioactivity is observed after the end of irradiation. The other one we call it the "on-line" where the capture gamma-rays is observed during the neutron bombardment. Actually, the sequence of events occurring during the most common type of nuclear reaction used in this analysis namely the neutron capture or (n, gamma) reaction, is well known for the people working in this field. The neutron interacts with the target nucleus via a non-elastic collision, a compound nucleus forms in an excited state. -
PGNAA Neutron Source Moderation Setup Optimization
Submitted to ‘Chinese Physics C PGNAA neutron source moderation setup optimization Zhang Jinzhao1(张金钊)Tuo Xianguo1(庹先国) (1.Chengdu University of Technology Applied Nuclear Techniques in Geoscience Key Laboratory of Sichuan Province,Chengdu 610059,China) Abstract: Monte Carlo simulations were carried out to design a prompt γ-ray neutron activation analysis (PGNAA) thermal neutron output setup using MCNP5 computer code. In these simulations the moderator materials, reflective materials and structure of the PGNAA 252Cf neutrons of thermal neutron output setup were optimized. Results of the calcuations revealed that the thin layer paraffin and the thick layer of heavy water moderated effect is best for 252Cf neutrons spectrum. The new design compared with the conventional neutron source design, the thermal neutron flux and rate were increased by 3.02 times and 3.27 times. Results indicate that the use of this design should increase the neutron flux of prompt gamma-ray neutron activation analysis significantly. Key word: PGNAA; neutron source; thermal neutron; moderation; reflection 1. Introduction study, Monte Carlo calculation was carried out for the Prompt gamma ray neutron activation analysis design of a 252Cf neutron source moderation setup for the (PGNAA) is a rapid, nondestructive, powerful analysis cement samples[7]. The model of Monte Carlo multielemental analysis technique, large samples of some simulation was verified by experiment[8, 9].We improve minor, trace light elements and is used in industrial the thermal neutron source yield rate of 252Cf neutron by control[1-5]. In a PGNAA analysis, the sample nuclear the PGNAA neutron source structure to the design. The composition is determined from prompt gamma rays calculation results for the new design were compared which produced through neutron inelastic scattering and with the previous, example: themal neutron flux rate, fast thermal neutron capture. -
Arxiv:1506.05417V2 [Physics.Ins-Det] 28 Jul 2016
http://dx.doi.org/10.1016/j.apradiso.2016.06.032 A precise method to determine the activity of a weak neutron source using a germanium detector M. J. M. Dukea, A. L. Hallinb, C. B. Kraussb, P. Mekarskib,∗, L. Sibleyb aSLOWPOKE Nuclear Reactor Facility, University of Alberta, Edmonton, AB T6G 2G7, Canada bDepartment of Physics, University of Alberta, Edmonton, AB T6G 2E1, Canada Abstract A standard high purity germanium (HPGe) detector was used to determine the previously unknown neutron activity of a weak americium-beryllium (AmBe) neutron source. γ rays were created through 27Al(n,n0), 27Al(n,γ) and 1H(n,γ) reactions induced by the neutrons on aluminum and acrylic disks, respectively. These γ rays were measured using the HPGe detector. Given the unorthodox experimental arrangement, a Monte Carlo simulation was developed to model the efficiency of the detector system to determine the neutron activity from the measured γ rays. The activity of our neutron source was determined to be 307.4 ± 5.0 n/s and is consistent for the different neutron-induced γ rays. Keywords: neutron activation, germanium detector, simulation, spectroscopy, activity determination 1. Introduction As neutrons are difficult to detect, determining the absolute activity of a neutron source is challenging. This difficulty increases as the activity of the source decreases. Sophisticated techniques exist for neutron activity measure- ments, including the manganese bath technique[1], proton recoil techniques[2] and the use of 3He proportional counters[3]; nevertheless, the development of a method utilizing commonly available high purity germanium (HPGe) detectors would be advantageous. HPGe's are an industry standard for measuring γ ray energies to high preci- sion. -
1663-29-Othernuclearreaction.Pdf
it’s not fission or fusion. It’s not alpha, beta, or gamma dosimeter around his neck to track his exposure to radiation decay, nor any other nuclear reaction normally discussed in in the lab. And when he’s not in the lab, he can keep tabs on his an introductory physics textbook. Yet it is responsible for various experiments simultaneously from his office computer the existence of more than two thirds of the elements on the with not one or two but five widescreen monitors—displaying periodic table and is virtually ubiquitous anywhere nuclear graphs and computer codes without a single pixel of unused reactions are taking place—in nuclear reactors, nuclear bombs, space. Data printouts pinned to the wall on the left side of the stellar cores, and supernova explosions. office and techno-scribble densely covering the whiteboard It’s neutron capture, in which a neutron merges with an on the right side testify to a man on a mission: developing, or atomic nucleus. And at first blush, it may even sound deserving at least contributing to, a detailed understanding of complex of its relative obscurity, since neutrons are electrically neutral. atomic nuclei. For that, he’ll need to collect and tabulate a lot For example, add a neutron to carbon’s most common isotope, of cold, hard data. carbon-12, and you just get carbon-13. It’s slightly heavier than Mosby’s primary experimental apparatus for doing this carbon-12, but in terms of how it looks and behaves, the two is the Detector for Advanced Neutron Capture Experiments are essentially identical. -
THERMAL NEUTRON DETECTION by ACTIVATION of Caso4dy + Kbr THERMOLUMINESCENT PHOSPHORS
THERMAL NEUTRON DETECTION BY ACTIVATION OF CaSO4Dy + KBr THERMOLUMINESCENT PHOSPHORS Ana Maria Pinho Leite Goidon and R. Muccillo PUBLICAÇÃO IEA 527 MAIO/1979 IEA-Pub-527 CONSELHO DELIBERATIVO MEMBROS Klaus Riinach - Pmidann Roberto D'Utra Vaz Helcio Modatto da Ceuta Ivano Humbart Marchati Admar Ctrvellini PARTICIPANTES Ragina Elisabet* Azevedo Btratta FléVio Gori SUPERINTENDENTE Hômulo Ribeiro Piaroni PUBLICAÇÃO IEA 627 MAIO/1078 IEA-Pub-627 THERMAL NEUTRON DETECTION BY ACTIVATION OF CtóO40y + KBr THERMOLUMMESCENT PHOSPHORS Am Mtrla Pbtho Ltttt Gordon md R. MuecHIo CENTRO DE PROTEÇÃO RAOIOLÓGICA E OOSIMETRIA CPRDAMD 041 oi INMOIA ATÔMICA PAULO - MAML S*i* PUBLICAÇÃO IEA INIS Ctttgoriw and Dticripmri E4t B26 Thtrinolumfntfctnt dotimvtry Nfutfon dctictlon CUchim wHam Tiwrmoluml NOM: A **m. ***** • HMMttM THERMAL NEUTRON DETECTION BY ACTIVATION OF CaSO4£ry THERMOLUMINESCF.NT PHOSPHORS* Ana Maria Pinho Leite Gofdon and R. Muceillo ABSTRACT Thermolumineicenoe (TLI itudiei to detect thermal neutron» were performed in cold pressed CsS04:0,1%Dy • KBr eemplei. The detection it bewd on the Mil irradietion of the CeSO^Dy TL phosphor by the Br iiotopet activeted by exposure to a mixed neutrongemme field. In 1970 a new method for the detection of thermal neutrons by .the Thermoluminescence |TL) auto-activation technique was proposed . It consists in the measurement of the TL output of a phosphor previously exposed to a neutron-gamma field, thermally annealed to bleach the radiation effects, ang stored to undergo self-irradiation due to the decay of the thremal neutron activation products. The TL output can then be related to the activation of the phosphor and consequently to the thermal neutron fluence.