Nuclear Data Sheets最新文献

{"title":"Nuclear Data Sheets for A=123","authors":"Jun Chen","doi":"10.1016/j.nds.2021.05.001","DOIUrl":"10.1016/j.nds.2021.05.001","url":null,"abstract":"<div><p>Experimental nuclear structure and decay data are evaluated for all of 15 known nuclides of mass 123 (Ru, Rh, Pd, Ag, Cd, In, Sn, Sb, Te, I, Xe, Cs, Ba, La, Ce). For each nuclide, detailed evaluated spectroscopic information is presented in each reaction and decay, and the best values combining all available data are recommended for level properties, <em>γ</em> and <em>β</em> radiations, and other spectroscopic properties. No excited states have been identified in ¹²³Ru, ¹²³Rh and ¹²³Pd. For ¹²³Ag, the long-predicted 1/2⁻ <em>β</em>-emitting isomer has been identified at 60-keV by 2019Ch24 recently, resolving unknown excitation energies in the level scheme that was previously available only from isomeric decays of two isomers (202 ns and 393 ns) with the position and spin-parity of the former remaining unknown. Significant discrepancies exist between data on high-spin sequences based on 11/2⁽⁻⁾ isomer in ¹²³Cd (2002Hw01 and 2016Re05), which needs to be resolved with further experimental investigation. In ¹²³Cs, the 114-ns isomer as the <em>π</em>g_9/2 bandhead proposed at 231.6+x by 2000Gi12 has been resolved by 2004Si26 and 2004Si27 to be the 328-keV level that is proposed by 2000Gi12 as a separate level. Excited states in ¹²³La and ¹²³Ce have only been studied via (HI, xn<em>γ</em>) reactions, with their base levels and thus excitation energies remaining unknown. The <em>β</em>⁻ decay schemes for daughter nuclide ¹²³Cd, ¹²³In and ¹²³Sn and the <em>ε</em> decay schemes for ¹²³Xe, ¹²³Cs and ¹²³Ba are considered incomplete due to large gaps between the highest observed excited levels and the Q-values. ¹²³Sn, ¹²³Sb, ¹²³Te and ¹²³I are the most extensively studied nuclides via various reactions and decays. This work supersedes earlier full evaluations of A=123 by 2004Oh11, 1993Oh12, 1980Ta02 and 1972Au10.</p></div>","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.nds.2021.05.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44704580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nuclear Data Sheets Symbols and Abbreviations","authors":"","doi":"10.1016/S0090-3752(21)00031-4","DOIUrl":"https://doi.org/10.1016/S0090-3752(21)00031-4","url":null,"abstract":"","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0090-3752(21)00031-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91779556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extensive Study of the Quality of Fission Yields from Experiment, Evaluation and GEF for Antineutrino Studies and Applications","authors":"K.-H. Schmidt ,&nbsp;M. Estienne ,&nbsp;M. Fallot ,&nbsp;S. Cormon ,&nbsp;A. Cucoanes ,&nbsp;T. Shiba ,&nbsp;B. Jurado ,&nbsp;K. Kern ,&nbsp;Ch. Schmitt","doi":"10.1016/j.nds.2021.04.004","DOIUrl":"10.1016/j.nds.2021.04.004","url":null,"abstract":"<div><p>The understanding of the antineutrino production in fission and the theoretical calculation of the antineutrino energy spectra in different, also future, types of fission reactors rely on the application of the summation method, where the individual contributions from the different radioactive nuclides that undergo a beta decay are estimated and summed up. The most accurate estimation of the independent fission-product yields is essential to this calculation. This is a complex task because the yields depend on the fissioning nucleus and on the energy spectrum of the incident neutrons.</p><p>In the present contribution, the quality of different sources of information on the fission yields is investigated, and the benefit of a combined analysis is demonstrated. The influence on antineutrino predictions is discussed.</p><p>In a systematic comparison, the quality of fission-product yields emerging from different experimental techniques is analyzed. The traditional radiochemical method, which is almost exclusively used for evaluations, provides an unambiguous identification in <em>Z</em> and <em>A</em>, but it is restricted to a limited number of suitable targets, is slow, and the accuracy suffers from uncertainties in the spectroscopic nuclear properties. Experiments with powerful spectrometers, for example at LOHENGRIN, provide very accurate mass yields and a <em>Z</em> resolution for light fission products from thermal-neutron-induced fission of a few suitable target nuclei.</p><p>On the theoretical side, the general fission model GEF has been developed. It combines a few general theorems, rules and ideas with empirical knowledge. GEF covers almost all fission observables and is able to reproduce measured data with high accuracy while having remarkable predictive power by establishing and exploiting unexpected systematics and hidden regularities in the fission observables. In this article, we have coupled for the first time the GEF predictions for the fission yields to fission-product beta-decay data in a summation calculation of reactor antineutrino energy spectra. The first comparisons performed between the spectra from GEF and those obtained with the evaluated nuclear databases exhibited large discrepancies that highlighted the exigency of the modelisation of the antineutrino spectra and showing their usefulness in the evaluation of nuclear data. Additional constraints for the GEF model were thus needed in order to reach the level of accuracy required by the antineutrino energy spectra. The combination of a careful study of the independent isotopic yields and the adjunction of the LOHENGRIN fission-yield data as additional constraints led to a substantially improved agreement between the antineutrino spectra computed with GEF and with the evaluated data. The comparison of inverse beta-decay yields computed with GEF with those measured by the Daya Bay experiment shows the excellent level of predictiveness of the GEF model for the fundamen","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.nds.2021.04.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86080505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conception and Software Implementation of a Nuclear Data Evaluation Pipeline","authors":"G. Schnabel ,&nbsp;H. Sjöstrand ,&nbsp;J. Hansson ,&nbsp;D. Rochman ,&nbsp;A. Koning ,&nbsp;R. Capote","doi":"10.1016/j.nds.2021.04.007","DOIUrl":"10.1016/j.nds.2021.04.007","url":null,"abstract":"<div><p>We discuss the design and software implementation of a nuclear data evaluation pipeline applied for a fully reproducible evaluation of neutron-induced cross sections of ⁵⁶Fe above the resolved resonance region using the nuclear model code TALYS combined with relevant experimental data. The emphasis of this paper is on the mathematical and technical aspects of the pipeline and not on the evaluation of ⁵⁶Fe, which is tentative. The mathematical building blocks combined and employed in the pipeline are discussed in detail. In particular, an intuitive and unified representation of experimental data, systematic and statistical errors, model parameters and defects enables the application of the Generalized Least Squares (GLS) and its natural extension, the Levenberg-Marquardt (LM) algorithm, on a large collection of experimental data without the need for data reduction techniques as a preparatory step. The LM algorithm tailored to nuclear data evaluation takes into account the exact non-linear physics model to determine best estimates of nuclear quantities. Associated uncertainty information is derived from a second-order Taylor expansion at the maximum of the posterior distribution. We also discuss the pipeline in terms of its IT (=information technology) building blocks, such as those to efficiently manage and retrieve experimental data of the EXFOR library, which facilitates their appropriate correction, and to distribute computations on a scientific cluster. Relying on the mathematical and IT building blocks, we elaborate on the sequence of steps in the pipeline to perform the evaluation, such as the retrieval of experimental data, the correction of experimental uncertainties using marginal likelihood optimization (MLO) and after a screening of thousand TALYS parameters—including Gaussian process priors on energy dependent parameters—the fitting of about 150 parameters using the LM algorithm. The code of the pipeline including a manual and a Dockerfile for a simplified installation is available at <span>www.nucleardata.com</span><svg><path></path></svg>.</p></div>","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.nds.2021.04.007","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41934403","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Reference Database for Beta-Delayed Neutron Emission","authors":"P. Dimitriou ,&nbsp;I. Dillmann ,&nbsp;B. Singh ,&nbsp;V. Piksaikin ,&nbsp;K.P. Rykaczewski ,&nbsp;J.L. Tain ,&nbsp;A. Algora ,&nbsp;K. Banerjee ,&nbsp;I.N. Borzov ,&nbsp;D. Cano-Ott ,&nbsp;S. Chiba ,&nbsp;M. Fallot ,&nbsp;D. Foligno ,&nbsp;R. Grzywacz ,&nbsp;X. Huang ,&nbsp;T. Marketin ,&nbsp;F. Minato ,&nbsp;G. Mukherjee ,&nbsp;B.C. Rasco ,&nbsp;A. Sonzogni ,&nbsp;N.D. Scielzo","doi":"10.1016/j.nds.2021.04.006","DOIUrl":"https://doi.org/10.1016/j.nds.2021.04.006","url":null,"abstract":"<div><p>Beta-delayed neutron emission is important for nuclear structure and astrophysics as well as for reactor applications. Significant advances in nuclear experimental techniques in the past two decades have led to a wealth of new measurements that remain to be incorporated in the databases.</p><p>We report on a coordinated effort to compile and evaluate all the available <em>β</em>-delayed neutron emission data. The different measurement techniques have been assessed and the data have been compared with semi-microscopic and microscopic-macroscopic models. The new microscopic database has been tested against aggregate total delayed neutron yields, time-dependent group parameters in 6-and 8-group re-presentation, and aggregate delayed neutron spectra. New recommendations of macroscopic delayed-neutron data for fissile materials of interest to applications are also presented. The new Reference Database for Beta-Delayed Neutron Emission Data is available online at: <span>http://www-nds.iaea.org/beta-delayed-neutron/database.html</span><svg><path></path></svg>.</p></div>","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.nds.2021.04.006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138208064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dr. Cecil Lubitz (1925–2021)","authors":"CSEWG,&nbsp;Tim Trumbull,&nbsp;Mike Zerkle,&nbsp;Tom Sutton,&nbsp;Dave Brown","doi":"10.1016/j.nds.2021.04.001","DOIUrl":"10.1016/j.nds.2021.04.001","url":null,"abstract":"","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.nds.2021.04.001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41260440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Results from Recent NNSA and CEA Measurements of the 239Pu(n, f) Prompt Fission Neutron Spectrum","authors":"K.J. Kelly ,&nbsp;P. Marini ,&nbsp;J. Taieb ,&nbsp;M. Devlin ,&nbsp;D. Neudecker ,&nbsp;R.C. Haight ,&nbsp;G. Bélier ,&nbsp;B. Laurent ,&nbsp;P. Morfouace ,&nbsp;J.M. O'Donnell ,&nbsp;E. Bauge ,&nbsp;M.B. Chadwick ,&nbsp;A. Chatillon ,&nbsp;D. Etasse ,&nbsp;P. Talou ,&nbsp;M.C. White ,&nbsp;C.Y. Wu ,&nbsp;E.A. Bennett","doi":"10.1016/j.nds.2021.04.003","DOIUrl":"10.1016/j.nds.2021.04.003","url":null,"abstract":"<div><p>The National Nuclear Security Administration (NNSA)/DP French Alternative Energies and Atomic Energy Commission (CEA)/DAM agreement on cooperation on fundamental science is a U.S.-French collaborative effort to combine intellectual and experimental resources and further the relevant nuclear science. Recently, both the NNSA and CEA experimental teams performed high-statistics measurements of the ²³⁹Pu(n, f) prompt fission neutron spectrum (PFNS) at the Los Alamos Neutron Science Center, both of which were recently published in the journal Physical Review C. These separate measurements used the same experimental area and a common neutron detector array, but differ in many aspects, including background assessments, data acquisition systems and philosophies, fission detectors, and PFNS extraction techniques. Hence, some aspects of the experimental methods and associated uncertainties are highly correlated while others are independent. The results from both measurements broke new ground for PFNS measurements given their higher accuracy and more detailed study of corrections necessary for the measured quantity compared to existing literature measurements, and both will significantly impact PFNS nuclear data evaluations for the foreseeable future. The focus of this work is to document a comparison of the results from these distinct measurements in terms of the acquired data, the PFNS results, and the measured average PFNS energies. While systematic differences between the PFNS results are present on the 1–3% level, the acquired data relative to each respective measurement at low incident neutron energies are in remarkable agreement, as are the conclusions regarding the magnitude and position of features in the PFNS relating to second-chance fission, third-chance fission, and pre-equilibrium neutron emission.</p></div>","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.nds.2021.04.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44595358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Upgrade of IAEA recommended data of selected nuclear reactions for production of PET and SPECT isotopes","authors":"A. Hermanne ,&nbsp;F.T. Tárkányi ,&nbsp;A.V. Ignatyuk ,&nbsp;S. Takács ,&nbsp;R. Capote","doi":"10.1016/j.nds.2021.04.008","DOIUrl":"10.1016/j.nds.2021.04.008","url":null,"abstract":"<div><p>An IAEA research project was dedicated to the compilation, evaluation and recommendation of cross-section data for the accelerator production of ¹¹C, ¹³N, ¹⁵O, ¹⁸F, ⁶⁴Cu, and ¹²⁴I positron-emitting radionuclides clinically used for PET imaging, and for the accelerator production of two gamma emitters, ⁸¹Rb and ¹²³I, used in SPECT imaging. Cross sections for 19 charged-particle induced reactions that can be employed for radionuclide accelerator production were evaluated including uncertainties. The resulting reference cross-section data were obtained from Padé fits to selected and corrected experimental data, and integral thick target yields were subsequently deduced. Uncertainties in the fitted results were estimated via a Padé least-squares method with the addition of a 4% assessed systematic uncertainty to the estimated experimental uncertainty. Experimental data were also compared with comprehensive predictions available from the TENDL library that reflects the current status of theoretical modelling. All of the numerical reference cross-section data with their corresponding uncertainties and deduced integral thick target yields are available on-line at the IAEA-NDS medical portal <span>www-nds.iaea.org/medportal/</span><svg><path></path></svg> and also at the IAEA-NDS web page <span>www-nds.iaea.org/medical/</span><svg><path></path></svg>.</p></div>","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.nds.2021.04.008","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90487512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Newly Evaluated Neutron Reaction Data on Chromium Isotopes","authors":"G.P.A. Nobre ,&nbsp;M.T. Pigni ,&nbsp;D.A. Brown ,&nbsp;R. Capote ,&nbsp;A. Trkov ,&nbsp;K.H. Guber ,&nbsp;R. Arcilla ,&nbsp;J. Gutierrez ,&nbsp;A. Cuadra ,&nbsp;G. Arbanas ,&nbsp;B. Kos ,&nbsp;D. Bernard ,&nbsp;P. Leconte","doi":"10.1016/j.nds.2021.04.002","DOIUrl":"10.1016/j.nds.2021.04.002","url":null,"abstract":"<div><p>Neutron reaction data for the set of major chromium isotopes were reevaluated from the thermal energy range up to 20 MeV. In the low energy region, updates to the thermal values together with an improved R-matrix analysis of the resonance parameters characterizing the cluster of large s-wave resonances for ^50,53Cr isotopes were performed. In the intermediate and high energy range up to 20 MeV, the evaluation methodology used statistical nuclear reaction models implemented in the EMPIRE code within the Hauser-Feshbach framework to evaluate the reaction cross sections and angular distributions. Exceptionally, experimental data were used to evaluate relevant cross sections above the resonance region up to 5 MeV in the major 52Cr isotope. Evaluations were benchmarked with Monte Carlo simulations of a small suite of critical assemblies highly sensitive to Chromium data, and with the Oktavian shielding benchmark to judge deep penetration performance with a 14-MeV D-T neutron source. A significant improvement in performance is demonstrated compared to existing evaluations.</p></div>","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.nds.2021.04.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"98642991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nuclear Data Sheets Symbols and Abbreviations","authors":"","doi":"10.1016/S0090-3752(21)00022-3","DOIUrl":"https://doi.org/10.1016/S0090-3752(21)00022-3","url":null,"abstract":"","PeriodicalId":49735,"journal":{"name":"Nuclear Data Sheets","volume":null,"pages":null},"PeriodicalIF":3.7,"publicationDate":"2021-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/S0090-3752(21)00022-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138208063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}