DOCSLIB.ORG

Activation Cross Sections for Reactions Induced by 14 Mev Neutrons On

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Activation Cross Sections for Reactions Induced by 14 Mev Neutrons On Radiochim. Acta 93, 311–326 (2005) by Oldenbourg Wissenschaftsverlag, München Activation cross sections for reactions induced by 14 MeV neutrons on natural tin and enriched 112Sn targets with reference to 111In production via radioisotope generator 112Sn(n,2n)111Sn → 111In By Emil Betˇ ak´ 1,2,∗, Renata Mikołajczak3 , Joanna Staniszewska3, Stefan Mikołajewski4 and Edward Rurarz4 1 Institute of Physics, Slovak Academy of Sciences, 84511 Bratislava, Slovakia 2 Faculty of Philosophy and Sciences, Silesian University, 74601 Opava, Czech Rep. 3 Radioisotope Centre, 05-400 Otwock-Swierk,´ Poland 4 Sołtan Institute for Nuclear Studies, 05-400 Otwock-Swierk,´ Poland (Received March 20, 2004; accepted in final form January 10, 2005) Activation cross sections / Ge detector / medicine. Due to the short half-life of 113mIn its application Neutron-induced reactions / γ-ray spectroscopy / is limited to rapid physiological studies that can be scanned Tin region / Neutron generator within a maximum of 4 to 8 hours. It is still in use, because it also allows repeated investigations within few hours. The preparation of 113Sn → 113mIn generator requires the use of γ Summary. We measured activation cross sections via -ray high-flux reactor and a strongly enriched 112Sn target in the spectroscopy using high-purity germanium detectors for 16 reaction 112Sn(n,γ)113Sn. reactions induced by (14.4 ±0.2) MeV neutrons on isotopes of tin. The cross sections are: An alternative is the use of the longer-lived (carrier- free) 111In. Medical investigators have shown that 111In is σ(112 ( , )111 ) = ( ± ) Sn n 2n Sn 1104 43 mb, an important radionuclide for locating and imaging cer- σ(112Sn(n, p)112mIn) = (33.6 ±2.1) mb, tain tumors, visualization of the lymphatic system etc., σ(112Sn(n, p)112gIn) = (42.7±3.1) mb, σ(114Sn(n, 2n)113Sn) = (1270 ±115) mb, and is applied in myriad of labeling. For several in-vivo σ(114Sn(n, p)114m2In) = (20.5 ±1.1) mb, studies (e.g. the study of slow biological processes, for σ(115Sn(n, p)115mIn) = (35.2 ±2.6) mb, which the observation periods of 1 to 3 days after the σ(116Sn(n, p)116m2In) = (11.1 ±0.5) mb, administration are necessary), 111In has very favourable σ(117Sn(n, np)116m2In) = (1.35 ±0.11) mb, decay characteristics [1–3]. Its half-life is 2.8 days. The σ(117Sn(n, p)117mIn) = (4.5 ±0.4) mb, 100% electron-capture decay leads to an excited state σ(117Sn(n, p)117gIn) = (12.8±0.7) mb, of 111Cd. This state is deexcited by the cascade of the σ(117 ( , )117m ) = ( ± ) Sn n n Sn 246 21 mb, 171.3 keV and 245.4 keV gamma-rays having intensities σ(118 ( , )117m ) = ( ± ) Sn n 2n Sn 816 70 mb, of 90.3% and 94%, respectively. The relevant average en- σ(118Sn(n,α)115gCd) = (1.26 ±0.16) mb, σ(120 ( ,α)117m ) = ( . ± . ) ergies (and intensities) of conversion electrons are low, Sn n Cd 0 27 0 04 mb, . σ(120Sn(n,α)117gCd) = (0.29 ±0.06) mb and namely 144 6 keV (10%) and 218 6 keV (6%). The energy σ(124Sn(n, 2n)123mSn) = (590 ±26) mb. of the Auger electrons is only about 20 keV. These gamma- ray energies are in the optimum range of the photo-peak Two 112Sn targets enriched to 62.5% and 84%, respectively, were used for these measurements in addition to the natural efficiency for commercially available gamma cameras or tin. The cross sections were compared with experimental data scanners. They can be imaged either separately or jointly found in the literature, with published empirical formulae and (184 photons per 100 EC disintegrations). In the latter case with model calculations including also the pre-equilibrium an improved statistics or more rapid data accumulation is contribution. For reactions which do not involve protons from achieved. below the closed Z = 50 shell, the agreement to the data is As summarized in Table 11, the isotope 111In can be pro- reasonable, it is somewhat weaker for the (n, p) reactions duced either directly or indirectly via precursors: 111Sb and and still worse in the case of (n,α), where, however, the 111Sn. The list of reactions given in this table is not exhaus- pre-equilibrium component is not described properly by the tive; other reactions, may come into use in the future. models included so far. The possibility of production of The isotope 111In is usually produced by 4He bombard- 111Sn → 111In generator system is considered. ment of a silver target via the 109Ag(4He, 2n)111In reaction, by deuteron bombardment of a cadmium target (natural or 1. Introduction enriched), the nuclear reactions are there 110Cd(d, n)111In 111 ( , )111 113m and Cd d 2n In, or by proton bombardment of cad- Carrier-free In, which is commercially available from mium (natural and enriched), the nuclear reactions in this 113 = → the radioisotope generator system Sn (T1/2 115 d) 111,112,113,114 ( , )111 = 113m case are Cd p xn In (x 1–4) [6, 7]. In (T1/2 = 100 min), is being used extensively in nuclear *Author for correspondence (E-mail: [email protected]). 1 Table 1 has been constructed using the data of Refs. [4, 5]. 312 E. Betˇ ak´ et al. Table 1. Thresholds and Coulomb barri- ers for reactions leading to production of Reaction Nat. abund. Q-value Threshold Coulomb 111In. of target energy barrier (per cent) (MeV) (MeV) (MeV) 111Cd(p, n)111In 12.75 −1.644 1.66 8.49 112Cd(p, 2n)111In 24.07 −11.039 11.14 8.47 113Cd(p, 3n)111In 12.26 −17.579 17.73 8.45 114Cd(p, 4n)111In 28.86 −26.622 26.86 8.43 110Cd(d, n)111In 12.39 3.107 0 8.15 111Cd(d, 2n)111In 12.75 −3.868 3.94 8.13 109Ag(3He, n)111In 48.65 6.533 0 15.52 109Ag(4He, 2n)111In 48.65 −14.044 14.56 15.17 + + EC,β EC,β 112Sn(p, 2n)111Sb −→ 111Sn −→ 111In 0.95 −16.627 16.78 8.82 75 s 35 m 110Cd(3He, 2n)111Sn → 111In 12.39 −5.619 5.77 15.82 112Sn(γ, n)111Sn → 111In 0.95 −10.788 10.79 − 112Sn(n, 2n)111Sn → 111In 0.95 −10.788 10.89 − The yields of 111In from nuclear reactions induced However, 109Ag(3He, n)111In reaction is unsuitable for the by 4He on Ag are much lower than from reactions in production of 111In because its yield is too low [about which Cd (irrespective of whether enriched or natural) is 7.4 × 104 Bq (2 µCi)/µA h at EOB] for 40 MeV bombard- bombarded by protons [2.22 × 106 Bq (60 µCi)/µAh for ing 3He particles [6]. Comparative study on the above ways 109 4 111 111 Ag( He, 2n) In reaction at E4He = 24 MeV compared leading to In for a medium size medical cyclotrons shows to 2.22 × 108 Bq (6000 µCi)/µAh for 112Cd(p, 2n)111In that the highest yield is obtained in the two reactions on reaction with cadmium target enriched to 97% and to highly enriched 112,113Cd targets, namely 112Cd(p, 2n)111In 7 113 111 3.7 × 10 Bq (1000 µCi)/µA h for natural cadmium target (Ep ≤ 30 MeV) and Cd(p, 3n) In (Ep ≤ 60 MeV) [6]. at Ep = 22 MeV] [6]. The reason for our choice of an en- Due to the lack of relevant nuclear data, not much can be riched 113Cd target is the advantage of a larger yield, namely said about indirect methods of the 111In production (the last 6.1 × 108 Bq (16 500 µCi)/µAh forthe(p, 3n) reaction at four reactions in Table 1). 65 MeV compared to the yield of the (p, 2n) reaction on the The radionuclide 111In can be produced by 112Sn(γ, n) enriched 112Cd at 26 MeV and to the yield of the (p, n) reac- 111Sn → 111In using medium-energy electron accelerators. tion on an enriched 111Cd target using 16 MeV protons [6, 7]. The achieved production scale of tens of MBq of no- When preparation of 111In is carried out by bombard- carrier-added (NCA) 111In per several hours run [8 × 107 Bq ing the cadmium target with protons (deuterons), the 111In (2.2mCi)/µA h] is sufficient for many types of applica- activity at the end of bombardment (EOB) contains undesir- tions [9]. Small scale production of 111In (tens of kBq) has able contaminations of other indium radionuclides, namely been reported [10] for reactor irradiations utilizing the fast 109 110m 114m 112 111 In (T1/2 = 4.3h), In (T1/2 = 4.9h),and In (T1/2 = component of the neutron spectrum in the Sn(n, 2n) Sn 49.5 d). The first two of them have relatively short half-lives → 111In reaction. Another potential possibility of 111In pro- and a suitable waiting period is required after EOB to let di- duction is to make use of fast neutrons produced by neutron minish drastically their activities. The chemical separation generators, which are commonly used in many laboratories. of 111In from irradiated cadmium target cannot be performed The aim of this work is to obtain information on 111In before at least 99% of these radioisotopes has decayed. activities induced by 14 MeV neutrons bombarding 112Sn 114m The third mentioned nuclide In (with major Eγ in keV targets. Production rates and achievable radionuclidic pu- and Iγ in per cent: 191.6 (16.7), 558 (3.6), 725.2 (3.5)) has rity after chemical separation were determined.
Load more

Recommended publications
  • Specification for Low Alpha Lead in Wafer Bump Applications
    Application Notes 47 Molter Street Cranston, Rhode Island 02910-1032 401-781-6100 • [email protected] • www.technic.com Specification for Low Alpha Lead in Wafer Bump Applications Background Alpha particles are positively charged nuclear particles consisting of two protons bound to two neutrons. Alpha particles are emitted spontaneously in some types of radioactive decay. Although alpha particle emissions are capable of penetrating only short distances, they are pernicious in creating computer memory or logic faults known as “soft faults”. Soft faults are individual events that are difficult to detect and isolate. Intel engineers working with IBM Fishkill, NY first identified the problem in 1979. The C-DIP’s (ceramic package DRAM) of that era were plated with gold and the alpha emissions were traced to the gold plated kovar package lids. Uranium or thorium decay and generate alpha particles with energies as high as 8.78 MeV. A flux of 5 MeV is capable of penetrating 25 um of silicon, resulting in 1.4 M electron hole pairs. If the electron accumulation exceeds a specific charge depending on the operating voltage and well design of the device, the cell may switch from “1” to “0”. There is no permanent damage and therefore the defect is referred to as a “soft” error. Design projections indicate that as device voltages decrease their sensitivity to alpha emissions increases. Alpha emissions are also common from tin lead deposited in the form of bumps for flip chip applications. The potential is significant for tin lead bumps due to the number of bumps and their close proximity to the sensitive IC well structure.
    [Show full text]
  • (RAPID) Method to Nuclear Materials
    University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 5-2020 Development and Applications of the Rapid Analysis of Post- Irradiation Debris (RAPID) Method to Nuclear Materials Emilie Fenske University of Tennessee, [email protected] Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Recommended Citation Fenske, Emilie, "Development and Applications of the Rapid Analysis of Post-Irradiation Debris (RAPID) Method to Nuclear Materials. " PhD diss., University of Tennessee, 2020. https://trace.tennessee.edu/utk_graddiss/5883 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Emilie Fenske entitled "Development and Applications of the Rapid Analysis of Post-Irradiation Debris (RAPID) Method to Nuclear Materials." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Nuclear Engineering. Howard Hall, Major Professor We have read this dissertation and recommend its acceptance: Steven Skutnik, Alan Icenhour, Robert Counce, Benjamin Roach, Cole Hexel Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) Development and Applications of the Rapid Analysis of Post-Irradiation Debris (RAPID) Method to Nuclear Materials A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Emilie Fenske May 2020 Copyright © 2020 by Emilie Kiersten Fenske All rights reserved.
    [Show full text]
  • Thesis Front Matter
    Research Report on Development of analytical strategies to measure radioisotopes of tin in the environment Prepared by Mohammad Majibur Rahman Graduate Program (PhD) Supervisor: Dr. Ian Clark Co-supervisor: Dr. Liam Kieser Earth and Environmental Sciences: Specialization in Chemical and Environmental Toxicology Submitted to The Office of Graduate and Postdoctoral Studies Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Earth and Environmental Sciences: Specialization in Chemical and Environmental Toxicology DECEMBER 13, 2018 © Mohammad Majibur Rahman, Ottawa, Canada, 2018 This page has intentionally been left blank. Abstract Quantification of tin isotopes in environmental samples, particularly the radioactive 126Sn, is important for processes such as the biomonitoring of organotin species, long-term nuclear waste storage and treatment planning. The detection of 126Sn by mass spectrometric methods is, however, hampered by the presence of the stable 126Te isotope. Therefore, separation of tin from tellurium is crucial to minimize isobaric interferences that limit the quantification of 126Sn by Accelerator Mass Spectrometry (AMS) and other instrumental techniques. In the present study, three major accomplishments are discussed: i) development of an analytical strategy to separate tin from tellurium, ii) monitoring of anionic interferences in the separation of tin from tellurium, and iii) suppression of 126Te background to allow the detection of 126Sn by AMS. Section I (Chapter 2): In the first phase of the project, an analytical survey was carried out using four Eichrom resins (TRU, TEVA, UTEVA, and DGA) to identify a suitable solid phase chromatographic material to separate tin from tellurium. Standard metal solutions were spiked on batch tests in two acids (HCl and HNO3) at concentrations ranging from 0.20 to 6.0 mol L–1, and the spiked analytes in solution were measured by ICP-MS.
    [Show full text]
  • Arxiv:1006.4033V2 [Nucl-Ex] 8 Sep 2010
    Discovery of Calcium, Indium, Tin, and Platinum Isotopes S. Amos, J. L. Gross, M. Thoennessen∗ National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA Abstract Currently, twenty-four calcium, thirty-eight indium, thirty-eight tin and thirty-nine platinum isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented. arXiv:1006.4033v2 [nucl-ex] 8 Sep 2010 ∗Corresponding author. Email address: [email protected] (M. Thoennessen) Preprint submitted to Atomic Data and Nuclear Data Tables November 1, 2018 Contents 1. Introduction . 4 2. Discovery of 35−58Ca ................................................................................... 5 2.1. 36Ca ............................................................................................ 5 2.2. 37Ca ............................................................................................ 7 2.3. 38Ca ............................................................................................ 7 2.4. 39Ca ............................................................................................ 7 2.5. 40Ca ............................................................................................ 7 2.6. 41Ca ............................................................................................ 8 2.7. 42;43Ca .........................................................................................
    [Show full text]
  • Arxiv:2006.05774V1 [Nucl-Ex] 10 Jun 2020 Bevddi Observed Aoaois Hl Ie,Cnd 0 1P0 K0J Canada River, Chalk Laboratories, Keywords: Pairs
    Systematic reduction of the proton-removal cross section in neutron-rich medium-mass nuclei J. D´ıaz-Cort´esa, J. Benlliurea, J.L. Rodr´ıguez-S´ancheza, H. Alvarez-Pol´ a, T. Aumannb, C.A. Bertulanic, B. Blankd, E. Casarejosa,1, D. Cortina-Gila, D. Dragosavaca, V. F¨ohre, A. Garganof, M. Gasc´ona, W. Gawlikowiczh, A. Heinzi, K. Helariuttaj, A. Keli´c-Heile, S. Luki´ce, F. Montese,2, D. P´erez-Loureiroa,3, L. Pie´nkowskig, K-H. Schmidte, M. Stanioue, K. Suboti´ck, K. S¨ummerere, J. Taiebl, A. Trzci´nskag aIGFAE, Universidade de Santiago de Compostela, E-15782 Spain bInstitut f¨ur Kernphysik, Technische Universit¨at Darmstadt, 64289 Darmstadt, Germany cTexas A&M University-Commerce, 75428 Commerce, Texas, United States of America dCentre d’Etudes Nucleaires, F-33175 Bordeaux-Gradignan Cedex, France eGSI Helmholtzzentrum f¨ur Schwerionenforschung, D-64291 Darmstadt, Germany fIstituto Nazionale di Fisica Nucleare, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy gHeavy Ion Laboratory, University of Warsaw, PL-02-093 Warsaw, Poland hCardinal Stefan Wyszynski University, PL-01-938 Warsaw, Poland iChalmers University of Technology, SE-41296 Gothenburg, Sweden jUniversity of Helsinki, FI-00014 Helsinki, Finland kInstitute of Nuclear Sciences Vinˇca, University of Belgrade, 11001 Belgrade, Serbia lCEA, DAM, DIF F-91297 Arpajon, France Abstract Single neutron- and proton-removal cross sections have been systematically measured for 72 medium-mass neutron- rich nuclei around Z=50 and energies around 900A MeV using the FRagment Separator (FRS) at GSI. Neutron- removal cross sections are described by considering the knock-out process together with initial- and final-state inter- actions.
    [Show full text]
  • Radiation Therapy and Dosing Material Transport Methodology Robert O'brien University of Nevada, Las Vegas, [email protected]
    UNLV Theses, Dissertations, Professional Papers, and Capstones 12-1-2016 Radiation Therapy and Dosing Material Transport Methodology Robert O'brien University of Nevada, Las Vegas, [email protected] Follow this and additional works at: https://digitalscholarship.unlv.edu/thesesdissertations Part of the Biomechanical Engineering Commons, Biomedical Commons, and the Biomedical Devices and Instrumentation Commons Repository Citation O'brien, Robert, "Radiation Therapy and Dosing Material Transport Methodology" (2016). UNLV Theses, Dissertations, Professional Papers, and Capstones. 2891. https://digitalscholarship.unlv.edu/thesesdissertations/2891 This Dissertation is brought to you for free and open access by Digital Scholarship@UNLV. It has been accepted for inclusion in UNLV Theses, Dissertations, Professional Papers, and Capstones by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. RADIATION THERAPY AND DOSING MATERIAL TRANSPORT METHODOLOGY By Robert James O’Brien Master of Science, Materials and Nuclear Engineering University of Nevada, Las Vegas 2006 Bachelor of Science, Mechanical Engineering University of Nevada, Las Vegas 2005 Bachelor of Science, Applied Physics University of Nevada, Las Vegas 2005 A dissertation submitted in partial fulfillment of the requirements for the Doctor of Philosophy in Engineering – Mechanical Engineering Department of Mechanical Engineering Howard R. Hughes College of Engineering The Graduate College University of Nevada, Las Vegas December 2016 Copyright by Robert O’Brien, 2017 All Rights Reserved Dissertation Approval The Graduate College The University of Nevada, Las Vegas November 16, 2016 This dissertation prepared by Robert James O’Brien entitled Radiation Therapy and Dosing Material Transport Methodology is approved in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Engineering – Mechanical Engineering Department of Mechanical Engineering William Culbreth, Ph.D.
    [Show full text]
  • A New Method of Pure 111In Production by Proton-Induced Nuclear Reactions with Enriched 112Sn 19 Consequently with Low Activity)
    NUKLEONIKA 2007;52(1):17−27 ORIGINAL PAPER 111 A new method of pure In production Emil Bìták, Edward Rurarz, by proton-induced nuclear reactions Stefan Mikołajewski, with enriched 112Sn Jolanta Wojtkowska Abstract. We aimed at finding out a simple and reliable way of 111In production with the highest radionuclide purity from its grand parent 111Sb and parent 111Sn nuclei, produced by the 112Sn(p,2n)111Sb and 112Sn(p,pn)111Sn reactions, respectively. The target was a metallic 112Sn sample enriched to 84%. We have measured activation cross sections for seven reactions on an enriched 112Sn sample induced by 23.6 ± 0.8 MeV energy protons. Gamma-ray spectroscopy with 55 60 high-purity germanium detectors has been used. We also identified the activities of Co (T1/2 = 17.5 h) and Cu (T1/2 = 23.7 min) in proton beam monitoring Ni foils, induced in the natNi(p,X)55Co and natNi(p,X)60Cu reactions at 22.8 MeV proton energy. The cross sections determined for these reactions are: σ[natNi(p,X)55Co] = 36.6 ± 4 mb and σ[natNi(p,X)60Cu] = 64.4 ± 7 mb. The measured cross sections of reactions on tin isotopes are: σ[112Sn(p,n)112Sb] = 4 ± 0.8 mb; σ[112Sn(p,2n)111Sb] = 182 ± 26 mb; σ[112Sn(p,pn)111Sn] = 307 ± 35 mb; σ[114Sn(p,2n)113Sb] = 442 ± 52 mb; σ[117Sn(p,n)117Sb] = 15 ± 3 mb; σ[117Sn(p,p’γ)117mSn] = 0.37 ± 0.06 mb; σ[115Sn(p,2p)114m2In] = 0.01 ± 0.002 mb.
    [Show full text]
  • Stdin (Ditroff)
    50Ma02 The Hyper®ne Structure of the Stable Isotopes of Indium A. K. Mann, P. Kusch, Phys. Rev. 77, 427 (1950). 50Ma03 The Beta-Spectrum of Ca45 P. Macklin, L. Feldman, L. Lidofsky, C. S. Wu, Phys. Rev. 77, 137 (1950). 50Ma05 Study of Neodymium and Promethium Activities Induced by Neutron Irradiation of Neodymium J. A. Marinsky, L. E. Glendenin, NNES 9, 1264 (1950). 50Ma14 New Isotope of Neptunium L. B. Magnusson, S. G. Thompson, G. T. Seaborg, Phys. Rev. 78, 363 (1950). 50Ma15 The Fission Yield of Xe133 and Fine Structure in the Mass Yield Curve J. Macnamara, C. B. Collins, H. G. Thode, Phys. Rev. 78, 129(1950). 50Ma27 D. G. E. Martin, H. O. W. Richardson, Proc. Phys. Soc. (London) 63A, 223 (1950). 50Ma29 Neutron De®cient Isotopes of Iodine L. Marquez, I. Perlman, Phys. Rev. 78, 189 (1950). 50Ma50 A Table of Nuclear Moments, January 1950 J. E. Mack, Revs. Modern Phys. 22, 64 (1950). 50Ma65 R. Malm, W. W. Buechner, Phys. Rev. 80, 771 (1950). 50Ma76 The Natural Radioactivity of In115 E. A. Martell, W. F. Libby, Phys. Rev. 80, 977 (1950). 50Mc12 Radiation from Au197*(7x10-9 sec) F. K. McGowan, Phys. Rev. 78, 325A (1950). 50Mc22 Short-Lived Isomers F. K. McGowan, ORNL-694, p. 19 (1950). 50Mc60 A 5.7 x 10-9 sec Isomeric State in Ir191 F. K. McGowan, Phys. Rev. 79, 404 (1950). 50Mc64 A3x10-9 sec. Isomeric State in Eu153 F. K. McGowan, Phys. Rev. 80, 482 (1950). 50Mc79 A 1.7 x 10-9 sec Isomeric State in Er166 F.
    [Show full text]
  • Stable Isotope Separation in Calutrons
    Printed ill tho llnitzd Statss ot 4mcm 4vailsble frurii Nations' Technical Information Service U S :3ep?rtmelli uf Commerce 5285 Port 4oyal Cosd Spririizflald Viryinis 22161 NTlS ptwiodes P~III~~Copy ,498, Microfiche P,C1 I his rcpoti \*!is prspxed as an account of >,dSi-k sponsored by a3 agsncy of the United Sraies Governr;,ent. Neither thc !J nited Skiics i<n.~cti $IK~: nor any agency th2reof. no? any of thzir employoes, (ciakc?.Aijy ivarranty, express or irripiled, or assunias any legal liability or responsibility for ihe accuracy. compleienass, or usefulness of any inforriraiton. ;p ius, product, or process disclosed, or represents that its usewould not infr privately o-v?d ilghts Rcferencc herein to ai-y specific commercial product, process, or service by trade nziile, Zi'adei*lark, manufacturer, or otherwise, does not necsssarily constitute or imply its enduisemcat, recorn,n faVOiii-,g by ille United States(;ovc;riiiie!ii 01- any Zgency thereof Th opinions of auiihols cxp:essed here:!: d~ ~iui neccssarily statc or refisc?!host of the United Sta?ezGovernmer:?or any ngcncy therccf. ____ ___________... ..... .____ ORNL/TM-10356 OPERATIONS DIVISION STABLE ISOTOPE SEPARATION IN CALUTRONS: FORTY YEARS OF PRODUCTION AND DISTRIBUTION W. A. Bell J. G. Tracy Date Published: November 1987 Prepared by the OAK RIDGE NATIONAL LABORATORY Oak Ridge, Tennessee 37831 operated by MARTIN MARIETTA ENERGY SYSTEMS, INC. for the U.S. DEPARTMENT OF ENERGY under Contract No. DE-AC05-840R21400 iti CONTENTS Page ACKNOWLEDGMENTS ................................................. iv I. INTRODUCTION .............................................. 1 11. PROGRAM EVOLUTION ......................................... 1 111. RESEARCH AND DEVELOPMENT .................................. 5 IV. CHEMISTRY ................................................. 8 V.
    [Show full text]
  • Francis W. Aston
    FRANCIS W. A STON Mass spectra and isotopes Nobel Lecture, December 12, 1922 Dalton’s statement of the Atomic Theory, which has been of such incalcu- lable value in the development of chemistry, contained the postulate that "atoms of the same element are similar to one another, and equal in weight". The second part of this postulate cannot, in general, be tested by chemical methods, for numerical ratios are only to be obtained in such methods by the use of quantities of the element containing countless myriads of atoms. At the same time it is somewhat surprising, when we consider the complete absence of positive evidence in its support, that no theoretical doubts were publicly expressed until late in the nineteenth century. There are two methods by which the postulate can be tested experi- mentally, either by comparing the weights of the individual atoms, or al- ternatively by demonstrating that samples of an element can exist which though chemically identical yet have different atomic weights. The latter method, by which the existence of isotopes was first proved, has been fully dealt with in the previous lecture by Professor Soddy. The more direct method, with which this lecture is concerned, can be applied by means of the analysis of positive rays. The condition for the development of these rays is briefly ionization at low pressure in a strong electric field. Ionization, which may be due to col- lisions or radiation, means in its simplest case the detachment of one electron from a neutral atom. The two resulting fragments carry charges of electricity of equal quantity but of opposite sign.
    [Show full text]
  • The Radiochemistry of Indium
    E958r i C.9.. National Academy v“ of Sciences 1National Research Council NUCLEAR SCIENCE SERIES The Radiochemistry of Iridium 3“#L7 :, ,fy% COMMITTEE ON NUCLEAR SCIENCE L.F.CUR~, Chafrman ROBLEY D.EVANS,ViceChuirmun NationalBureauofStadarde MaeeachueetteInetituteofTechnology J.A.DeJUREN,Secretury WeMnghouee ElectricCorporation H.J.CURTIS W. WAYNE MEINKE BrookhavenNationalLaboratog UniversityofMichigan SAMUEL EPSTELN ROBERT L.PLAT ZMAN Callforn.laInetItuteofTechuol~ ArgonoeNationalLeboratmg HERBERT GOLDSTEIN A. H.SNELL NwlearDevelopmentCorporationof Of&RidgeNationalLaboratory America E.A.UEHLING H.JoGOMBERG Unlveret@ofWaehlngton UnlvereltyofMlcldgan D.M. VAN PATTER E.D.KLEMA BartolReeearchFoundation NorthweetarnUniveretty G.G.MANOV Tmcerleb,Inc. LIAISON MEMBERS PAUL C.AEBERSOLD W. D.URRY AtomicEne~ Commieaion U.S.AlrForce J.HOWARD MaMILLEN WILLIAM E.WRIGHT NationalscienceFoudatkon OfficeofNavalReseamh SUBCOMMIllEE ON RADIOCHEMISTRY W. WAYNE MEINKE,Chutrwaam HAROLD SURBY UnlvereityofMichtsan MoundLahoretory GREGORY R.CHOPPIN GEORGE LEDDICOTTE FlorklaStateUnlvereity OakRidgeNationalLaboratory GEORGE A.COWAN JULIAN NTELSEN LoeAlamoeSckmtlflcLaboratog Hanfod Lahoratoriee ARTHUR W. FAIRHALL ELLISP.STEINBERG UnlvereltyofWashington ArgonneNationalLaboratory JEROME HUDIS PETER C.STEVENSON Brddmven NationalLaboratory UniversityofCaltfornta(Llvemore) EARL HYDE LEO YAFFE UnlvereltyofCalifornia(Bgrkeley) McGU1 Unlvereity CONSULTANTS NATHAN BALLOU WILLIAM MARLOW Naval~iologlcalDefeneeLaboratory NationalBureauofStandamie JAMES DeVOE UntveieityofMhhigan
    [Show full text]
  • Tail As the .:J:J Ref~ Ax; ¥10 'T:"-T Dfgtj..Tl ~ ,..U~ [.!Lt·V
    Anomalies in the Fermi Effect • ... be conbi~e~,.CL bjvsome as equally probable, or even more ~:Sa"b ~ s tfi:aR the fixst=aite"!'f'l'autive •. While we "ffhal.l ~ 4 ~ a.~.a,.fyf---c __.,. emphasize the pas si bili ty o 4his eeeond vie'fvj~we will · t.A----~ . (J ¢::6 d.t"ia: -; ~~.... ~. ,,-..A( ~ not discuss £? in ~ etail as the .:j:j rEf~ ax; ¥10 't:"-t dfGtJ..tL ~ ,..u~ [.!lt·v ...... ~YJ ~- ~. r/ ~ This unequal treatment is not due to a biased opinion in . ~,.,,,~ . ~ !-'. ' 'M·•/. favour of one of e ·· ' views, and seems -t;o-..b€ just'fied (/~A rt• f.-# £r.~- .-/ ~ e.e i.o I~,_,_ "-!- H . .t:/ ,d"~ t~t .vrlk t.~ 1 ~-.. a : . , . - · by t h e fact that the f1Fst VJ:ew- leads \ to a number of p otentially pas si ble ~l r ( • (-(;;-- -~~ "1:1 /experiments wnich may decide / 3:-rr~~~ , ·o-: a ~ n. ~ , I~ - "/Z,_ - /t , .y /I(, " ,. /.. ' . .... I /7<Vt.. (,_.1' ~~ whereas it se5!ms to be diffipul t to think of cn ~. t'- ,.. (, ...... 1 #t.r t~- ....-.~..., "'<../ t<t.,.-< ""'"' t t( /'l'n J ( "t·C experiments,. ~t'O a:mc t · decision o·n-~ a - - - "' ANOMALIB.S IN TilE FERMI EFFECT 1) Amaldi, D'Agostino and Segre have found that neutrons Which have been slowed down by paraffin wax induce in indium two radio­ active half-life periods (16 eea. and 54 min.). T.A. Cha~ers and 2) I have subsequently reported that indium can also be comparatively strongly activated with a third period of several hours if irradiated by neutrons from a radon alpha-particle beryllium source in the ab- sence of hydrogen-containing substances, and we raised the question whether its existence can be satisfactorily explained without a new assumption.
    [Show full text]