Cosmogenic Nuclide Analysis
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Hetc-3Step Calculations of Proton Induced Nuclide Production Cross Sections at Incident Energies Between 20 Mev and 5 Gev
JAERI-Research 96-040 JAERI-Research—96-040 JP9609132 JP9609132 HETC-3STEP CALCULATIONS OF PROTON INDUCED NUCLIDE PRODUCTION CROSS SECTIONS AT INCIDENT ENERGIES BETWEEN 20 MEV AND 5 GEV August 1996 Hiroshi TAKADA, Nobuaki YOSHIZAWA* and Kenji ISHIBASHI* Japan Atomic Energy Research Institute 2 G 1 0 1 (T319-11 l This report is issued irregularly. Inquiries about availability of the reports should be addressed to Research Information Division, Department of Intellectual Resources, Japan Atomic Energy Research Institute, Tokai-mura, Naka-gun, Ibaraki-ken, 319-11, Japan. © Japan Atomic Energy Research Institute, 1996 JAERI-Research 96-040 HETC-3STEP Calculations of Proton Induced Nuclide Production Cross Sections at Incident Energies between 20 MeV and 5 GeV Hiroshi TAKADA, Nobuaki YOSHIZAWA* and Kenji ISHIBASHP* Department of Reactor Engineering Tokai Research Establishment Japan Atomic Energy Research Institute Tokai-mura, Naka-gun, Ibaraki-ken (Received July 1, 1996) For the OECD/NEA code intercomparison, nuclide production cross sections of l60, 27A1, nalFe, 59Co, natZr and 197Au for the proton incidence with energies of 20 MeV to 5 GeV are calculated with the HETC-3STEP code based on the intranuclear cascade evaporation model including the preequilibrium and high energy fission processes. In the code, the level density parameter derived by Ignatyuk, the atomic mass table of Audi and Wapstra and the mass formula derived by Tachibana et al. are newly employed in the evaporation calculation part. The calculated results are compared with the experimental ones. It is confirmed that HETC-3STEP reproduces the production of the nuclides having the mass number close to that of the target nucleus with an accuracy of a factor of two to three at incident proton energies above 100 MeV for natZr and 197Au. -
EXTRACTION of BERYLLIUM-10 from SOIL by FUSION Summary
EXTRACTION OF BERYLLIUM-10 FROM SOIL BY FUSION Summary This method is used to separate Be from soil and sediment samples, for AMS analysis. After adding Be carrier, the sample is fused with KHF2. Be is extracted from the fusion cake with hot water. K is removed by precipitation, the sample is dried to expel fluoride, and Be is recovered as Be(OH)2. Yields are typically 70-80 %, but can be increased by additional leaching of the fusion cake. Version Written by John Stone, 1996-2002. This version revised May 2004 by Greg Balco. Available at: http://depts.washington.edu/cosmolab/chem.html References If you use this method, please cite: Stone, J.O.H. (1998). A rapid fusion method for the extraction of Be-10 from soils and silicates. Geochimica et Cosmochimica Acta (Scientific comment) 62, 555-561. Sampling and grinding Mix and grind an unbiased ∼ 50-100 g sample of the material. If possible, mix the original sample bag before opening and take representative proportions of coarse and fine material. Fine soil, carbonate nodules, clay lumps, rock fragments, etc., all have different 10Be concentrations. Grinding homogenises the sample and ensures that these components are evenly represented in the small subsample used for the analysis. If the sample is wet, you will need to dry it before grinding. Initial sample drying Samples are best run in batches of four. This is because we currently have four Pt crucibles. Given more crucibles and sufficient hotplate space, batches of 8 or even 12 are equally feasible. ————————————————— UW Cosmogenic Nuclide Lab – 10Be fusion process 1 – Label and tare four disposable aluminum foil drying dishes and transfer a few grams of ground sediment to each with a steel spatula. -
Isotopegeochemistry Chapter4
Isotope Geochemistry W. M. White Chapter 4 GEOCHRONOLOGY III: OTHER DATING METHODS 4.1 COSMOGENIC NUCLIDES 4.1.1 Cosmic Rays in the Atmosphere As the name implies, cosmogenic nuclides are produced by cosmic rays colliding with atoms in the atmosphere and the surface of the solid Earth. Nuclides so created may be stable or radioactive. Radio- active cosmogenic nuclides, like the U decay series nuclides, have half-lives sufficiently short that they would not exist in the Earth if they were not continually produced. Assuming that the production rate is constant through time, then the abundance of a cosmogenic nuclide in a reservoir isolated from cos- mic ray production is simply given by: −λt N = N0e 4.1 Hence if we know N0 and measure N, we can calculate t. Table 4.1 lists the radioactive cosmogenic nu- clides of principal interest. As we shall, cosmic ray interactions can also produce rare stable nuclides, and their abundance can also be used to measure geologic time. A number of different nuclear reactions create cosmogenic nuclides. “Cosmic rays” are high-energy (several GeV up to 1019 eV!) atomic nuclei, mainly of H and He (because these constitute most of the matter in the universe), but nuclei of all the elements have been recognized. To put these kinds of ener- gies in perspective, the previous gen- eration of accelerators for physics ex- Table 4.1. Data on Cosmogenic Nuclides periments, such as the Cornell Elec- -1 tron Storage Ring produce energies in Nuclide Half-life, years Decay constant, yr the 10’s of GeV (1010 eV); while 14C 5730 1.209x 10-4 CERN’s Large Hadron Collider, 3H 12.33 5.62 x 10-2 mankind’s most powerful accelerator, 10Be 1.500 × 106 4.62 x 10-7 located on the Franco-Swiss border 26Al 7.16 × 105 9.68x 10-5 near Geneva produces energies of 36Cl 3.08 × 105 2.25x 10-6 ~10 TeV range (1013 eV). -
An Octad for Darmstadtium and Excitement for Copernicium
SYNOPSIS An Octad for Darmstadtium and Excitement for Copernicium The discovery that copernicium can decay into a new isotope of darmstadtium and the observation of a previously unseen excited state of copernicium provide clues to the location of the “island of stability.” By Katherine Wright holy grail of nuclear physics is to understand the stability uncover its position. of the periodic table’s heaviest elements. The problem Ais, these elements only exist in the lab and are hard to The team made their discoveries while studying the decay of make. In an experiment at the GSI Helmholtz Center for Heavy isotopes of flerovium, which they created by hitting a plutonium Ion Research in Germany, researchers have now observed a target with calcium ions. In their experiments, flerovium-288 previously unseen isotope of the heavy element darmstadtium (Z = 114, N = 174) decayed first into copernicium-284 and measured the decay of an excited state of an isotope of (Z = 112, N = 172) and then into darmstadtium-280 (Z = 110, another heavy element, copernicium [1]. The results could N = 170), a previously unseen isotope. They also measured an provide “anchor points” for theories that predict the stability of excited state of copernicium-282, another isotope of these heavy elements, says Anton Såmark-Roth, of Lund copernicium. Copernicium-282 is interesting because it University in Sweden, who helped conduct the experiments. contains an even number of protons and neutrons, and researchers had not previously measured an excited state of a A nuclide’s stability depends on how many protons (Z) and superheavy even-even nucleus, Såmark-Roth says. -
Compilation and Evaluation of Fission Yield Nuclear Data Iaea, Vienna, 2000 Iaea-Tecdoc-1168 Issn 1011–4289
IAEA-TECDOC-1168 Compilation and evaluation of fission yield nuclear data Final report of a co-ordinated research project 1991–1996 December 2000 The originating Section of this publication in the IAEA was: Nuclear Data Section International Atomic Energy Agency Wagramer Strasse 5 P.O. Box 100 A-1400 Vienna, Austria COMPILATION AND EVALUATION OF FISSION YIELD NUCLEAR DATA IAEA, VIENNA, 2000 IAEA-TECDOC-1168 ISSN 1011–4289 © IAEA, 2000 Printed by the IAEA in Austria December 2000 FOREWORD Fission product yields are required at several stages of the nuclear fuel cycle and are therefore included in all large international data files for reactor calculations and related applications. Such files are maintained and disseminated by the Nuclear Data Section of the IAEA as a member of an international data centres network. Users of these data are from the fields of reactor design and operation, waste management and nuclear materials safeguards, all of which are essential parts of the IAEA programme. In the 1980s, the number of measured fission yields increased so drastically that the manpower available for evaluating them to meet specific user needs was insufficient. To cope with this task, it was concluded in several meetings on fission product nuclear data, some of them convened by the IAEA, that international co-operation was required, and an IAEA co-ordinated research project (CRP) was recommended. This recommendation was endorsed by the International Nuclear Data Committee, an advisory body for the nuclear data programme of the IAEA. As a consequence, the CRP on the Compilation and Evaluation of Fission Yield Nuclear Data was initiated in 1991, after its scope, objectives and tasks had been defined by a preparatory meeting. -
Heavy Element Nucleosynthesis
Heavy Element Nucleosynthesis A summary of the nucleosynthesis of light elements is as follows 4He Hydrogen burning 3He Incomplete PP chain (H burning) 2H, Li, Be, B Non-thermal processes (spallation) 14N, 13C, 15N, 17O CNO processing 12C, 16O Helium burning 18O, 22Ne α captures on 14N (He burning) 20Ne, Na, Mg, Al, 28Si Partly from carbon burning Mg, Al, Si, P, S Partly from oxygen burning Ar, Ca, Ti, Cr, Fe, Ni Partly from silicon burning Isotopes heavier than iron (as well as some intermediate weight iso- topes) are made through neutron captures. Recall that the prob- ability for a non-resonant reaction contained two components: an exponential reflective of the quantum tunneling needed to overcome electrostatic repulsion, and an inverse energy dependence arising from the de Broglie wavelength of the particles. For neutron cap- tures, there is no electrostatic repulsion, and, in complex nuclei, virtually all particle encounters involve resonances. As a result, neutron capture cross-sections are large, and are very nearly inde- pendent of energy. To appreciate how heavy elements can be built up, we must first consider the lifetime of an isotope against neutron capture. If the cross-section for neutron capture is independent of energy, then the lifetime of the species will be ( )1=2 1 1 1 µn τn = ≈ = Nnhσvi NnhσivT Nnhσi 2kT For a typical neutron cross-section of hσi ∼ 10−25 cm2 and a tem- 8 9 perature of 5 × 10 K, τn ∼ 10 =Nn years. Next consider the stability of a neutron rich isotope. If the ratio of of neutrons to protons in an atomic nucleus becomes too large, the nucleus becomes unstable to beta-decay, and a neutron is changed into a proton via − (Z; A+1) −! (Z+1;A+1) + e +ν ¯e (27:1) The timescale for this decay is typically on the order of hours, or ∼ 10−3 years (with a factor of ∼ 103 scatter). -
A Guide to Naturally Occurring Radioactive Materials (NORM)
ABOUT NORM SOME NORM NUCLIDES OF SPECIAL INTEREST A Guide to Naturally There are three types of NORM: Occurring Radioactive • Cosmogenic – NORM produced by cosmic rays interacting with the Earth’s Materials (NORM) Beryllium 7 atmosphere; the most important Developed by the 3 7 14 examples are H (tritium), Be, and C. 7Be is being continuously formed in the DHS Secondary Reachback Program • Primordial – Sufficiently long-lived atmosphere by cosmic rays. Jet engines can March 2010 NORM for some to have survived from accumulate enough 7Be to set off before the formation of the Earth; there radiological alarms when being cleaned. are 20 primordial NORM nuclides with As defined by the International Atomic the most important being 40K, 232Th, Energy Agency (IAEA), Naturally 235U, and 238U. Polonium 210 Occurring Radioactive Materials • Daughters – When 232Th, 235U and 238U In the 238U decay chain 210Po is a distant (NORM) include all natural radioactive decay 42 different radioactive nuclides daughter of 226Ra. 210Po gained notoriety in materials where human activities have are formed (see below) with the most the 1960s as a radioactive trace component increased the potential for exposure in important being 222Rn, 226Ra, 228Ra and in cigarette smoke. Heavy use of phosphate comparison with the unaltered natural 228 Ac. fertilizers (which have trace amounts of out here. fold Next situation. If processing has increased 226Ra) can triple the amount of 210Po found the concentrations of radionuclides in a When 232Th, 235U and 238U decay a in tobacco. material then it is Technologically radioactive “daughter” nuclide is formed, Enhanced NORM (TE-NORM). -
Meteoric Be and Be As Process Tracers in the Environment
Chapter 5 Meteoric 7Be and 10Be as Process Tracers in the Environment James M. Kaste and Mark Baskaran 7 10 Abstract Be (T1/2 ¼ 53 days) and Be (T1/2 ¼ occurring Be isotopes of use to Earth scientists are the 7 1.4 Ma) form via natural cosmogenic reactions in the short-lived Be (T1/2 ¼ 53.1 days) and the longer- 10 atmosphere and are delivered to Earth’s surface by wet lived Be (T1/2 ¼ 1.4 Ma; Nishiizumi et al. 2007). and dry deposition. The distinct source term and near- Because cosmic rays that cause the initial cascade of constant fallout of these radionuclides onto soils, vege- neutrons and protons in the upper atmosphere respon- tation, waters, ice, and sediments makes them valuable sible for the spallation reactions are attenuated by tracers of a wide range of environmental processes the mass of the atmosphere itself, production rates of operating over timescales from weeks to millions of comsogenic Be are three orders of magnitude higher in years. Beryllium tends to form strong bonds with oxygen the stratosphere than they are at sea-level (Masarik and atoms, so 7Be and 10Be adsorb rapidly to organic and Beer 1999, 2009). Most of the production of cosmo- inorganic solid phases in the terrestrial and marine envi- genic Be therefore occurs in the upper atmosphere ronment. Thus, cosmogenic isotopes of beryllium can be (5–30 km), although there is trace, but measurable used to quantify surface age, sediment source, mixing production as oxygen atoms in minerals at the Earth’s rates, and particle residence and transit times in soils, surface are spallated (in situ produced; see Lal 2011, streams, lakes, and the oceans. -
Beryllium-10 Terrestrial Cosmogenic Nuclide Surface Exposure Dating of Quaternary Landforms in Death Valley
Geomorphology 125 (2011) 541–557 Contents lists available at ScienceDirect Geomorphology journal homepage: www.elsevier.com/locate/geomorph Beryllium-10 terrestrial cosmogenic nuclide surface exposure dating of Quaternary landforms in Death Valley Lewis A. Owen a,⁎, Kurt L. Frankel b, Jeffrey R. Knott c, Scott Reynhout a, Robert C. Finkel d,e, James F. Dolan f, Jeffrey Lee g a Department of Geology, University of Cincinnati, Cincinnati, Ohio, USA b School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA c Department of Geological Sciences, California State University, Fullerton, California, USA d Department of Earth and Planetary Science Department, University of California, Berkeley, Berkeley, CA 94720-4767, USA e CEREGE, BP 80 Europole Méditerranéen de l'Arbois, 13545 Aix en Provence Cedex 4, France f Department of Earth Sciences, University of Southern California, Los Angeles, California, USA g Department of Geological Sciences, Central Washington University, Ellensburg, Washington, USA article info abstract Article history: Quaternary alluvial fans, and shorelines, spits and beach bars were dated using 10Be terrestrial cosmogenic Received 10 March 2010 nuclide (TCN) surface exposure methods in Death Valley. The 10Be TCN ages show considerable variance on Received in revised form 3 October 2010 individual surfaces. Samples collected in the active channels date from ~6 ka to ~93 ka, showing that there is Accepted 18 October 2010 significant 10Be TCN inheritance within cobbles and boulders. This -
Production and Properties Towards the Island of Stability
This is an electronic reprint of the original article. This reprint may differ from the original in pagination and typographic detail. Author(s): Leino, Matti Title: Production and properties towards the island of stability Year: 2016 Version: Please cite the original version: Leino, M. (2016). Production and properties towards the island of stability. In D. Rudolph (Ed.), Nobel Symposium NS 160 - Chemistry and Physics of Heavy and Superheavy Elements (Article 01002). EDP Sciences. EPJ Web of Conferences, 131. https://doi.org/10.1051/epjconf/201613101002 All material supplied via JYX is protected by copyright and other intellectual property rights, and duplication or sale of all or part of any of the repository collections is not permitted, except that material may be duplicated by you for your research use or educational purposes in electronic or print form. You must obtain permission for any other use. Electronic or print copies may not be offered, whether for sale or otherwise to anyone who is not an authorised user. EPJ Web of Conferences 131, 01002 (2016) DOI: 10.1051/epjconf/201613101002 Nobel Symposium NS160 – Chemistry and Physics of Heavy and Superheavy Elements Production and properties towards the island of stability Matti Leino Department of Physics, University of Jyväskylä, PO Box 35, 40014 University of Jyväskylä, Finland Abstract. The structure of the nuclei of the heaviest elements is discussed with emphasis on single-particle properties as determined by decay and in- beam spectroscopy. The basic features of production of these nuclei using fusion evaporation reactions will also be discussed. 1. Introduction In this short review, some examples of nuclear structure physics and experimental methods relevant for the study of the heaviest elements will be presented. -
The Discoverers of the Ruthenium Isotopes
•Platinum Metals Rev., 2011, 55, (4), 251–262• The Discoverers of the Ruthenium Isotopes Updated information on the discoveries of the six platinum group metals to 2010 http://dx.doi.org/10.1595/147106711X592448 http://www.platinummetalsreview.com/ By John W. Arblaster This review looks at the discovery and the discoverers Wombourne, West Midlands, UK of the thirty-eight known ruthenium isotopes with mass numbers from 87 to 124 found between 1931 and 2010. Email: [email protected] This is the sixth and fi nal review on the circumstances surrounding the discoveries of the isotopes of the six platinum group elements. The fi rst review on platinum isotopes was published in this Journal in October 2000 (1), the second on iridium isotopes in October 2003 (2), the third on osmium isotopes in October 2004 (3), the fourth on palladium isotopes in April 2006 (4) and the fi fth on rhodium isotopes in April 2011 (5). An update on the new isotopes of palladium, osmium, iridium and platinum discovered since the previous reviews in this series is also included. Naturally Occurring Ruthenium Of the thirty-eight known isotopes of ruthenium, seven occur naturally with the authorised isotopic abun- dances (6) shown in Table I. The isotopes were fi rst detected in 1931 by Aston (7, 8) using a mass spectrograph at the Cavendish Laboratory, Cambridge University, UK. Because of diffi cult experimental conditions due to the use of poor quality samples, Aston actually only detected six of the isotopes and obtained very approximate Table I The Naturally Occurring Isotopes of Ruthenium Mass number Isotopic Abundance, % 96Ru 5.54 98Ru 1.87 99Ru 12.76 100Ru 12.60 101Ru 17.06 102Ru 31.55 104Ru 18.62 251 © 2011 Johnson Matthey http://dx.doi.org/10.1595/147106711X592448 •Platinum Metals Rev., 2011, 55, (4)• percentage abundances. -
Important Fission Product Nuclides Identification Method for Simplified Burnup Chain Construction
Title Important fission product nuclides identification method for simplified burnup chain construction Author(s) Chiba, Go; Tsuji, Masashi; Narabayashi, Tadashi; Ohoka, Yasunori; Ushio, Tadashi Journal of nuclear science and technology, 52(7-8), 953-960 Citation https://doi.org/10.1080/00223131.2015.1032381 Issue Date 2015-08 Doc URL http://hdl.handle.net/2115/62612 This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of nuclear science and Rights technology on 4 Aug 2015, available online: http://www.tandfonline.com/10.1080/00223131.2015.1032381 Type article (author version) File Information paper.pdf Instructions for use Hokkaido University Collection of Scholarly and Academic Papers : HUSCAP ARTICLE Typeset with jnst.cls <ver.1.84> Important fission product nuclides identification method for simplified burnup chain construction Go Chiba1 ∗, Masashi Tsuji1, Tadashi Narabayashi1, Yasunori Ohoka2, Tadashi Ushio2 1Graduate School of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628, Japan; 2Nuclear Fuel Industries, Ltd., 950 Asashiro-Nishi 1-chome, Kumatori, Osaka 590-0481, Japan A method of identifying important fission product (FP) nuclides which are included in a simplified burnup chain is proposed. This method utilizes adjoint nuclide number densities and contribution functions which quantify importance of nuclide number densities to the target nuclear characteristics: number densities of specific nuclides after burnup. Numer- ical tests with light water reactor (LWR) fuel pin-cell problems reveal that this method successfully identifies important FP nuclides included in a simplified burnup chain, with which number densities of target nuclides after burnup are well reproduced. A simpli- fied burnup chain consisting of 138 FP nuclides is constructed using this method, and its good performance for predictions of number densities of target nuclides and reac- tivity is demonstrated against LWR pin-cell problems and multi-cell problem including gadolinium-bearing fuel rod.