WorldWideScience

Sample records for cross sections systematic

  1. Systematics of fission cross sections at the intermediate energy region

    Energy Technology Data Exchange (ETDEWEB)

    Fukahori, Tokio; Chiba, Satoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    The systematics was obtained with fitting experimental data for proton induced fission cross sections of Ag, {sup 181}Ta, {sup 197}Au, {sup 206,207,208}Pb, {sup 209}Bi, {sup 232}Th, {sup 233,235,238}U, {sup 237}Np and {sup 239}Pu above 20 MeV. The low energy cross section of actinoid nuclei is omitted from systematics study, since the cross section has a complicated shape and strongly depends on characteristic of nucleus. The fission cross sections calculated by the systematics are in good agreement with experimental data. (author)

  2. Charged particle cross-section data and their systematization

    International Nuclear Information System (INIS)

    Nassif, S.

    1982-07-01

    The reaction cross-sections and the thick target yields of (α,αxn) and (α,xn), induced by the alpha particles from the Buenos Aires 60 inch synchrocyclotron for Cu, Y, Zr, Rh, Te, Ta, Au and Pb were obtained. The ''stocked foil'' method was applied. The ''nuclear spin density'' parameter was determined using a phenomenological approximation from the cross section data for 181 Ta(α,n) reaction producing isomeric pairs of sup(184m)Re and sup(184g)Re. The systematic behaviour of the present result and the results of other authors were demonstrated

  3. Photoneutron cross sections for {sup 59}Co. Systematic uncertainties of data from various experiments

    Energy Technology Data Exchange (ETDEWEB)

    Varlamov, V.V. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); Davydov, A.I. [Lomonosov Moscow State University, Physics Faculty, Moscow (Russian Federation); Ishkhanov, B.S. [Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); Lomonosov Moscow State University, Physics Faculty, Moscow (Russian Federation)

    2017-09-15

    Data on partial photoneutron reaction cross sections (γ, 1n), (γ, 2n), and (γ, 3n) for {sup 59}Co obtained in two experiments carried out at Livermore (USA) were analyzed. The sources of radiation in both experiments were the monoenergetic photon beams from the annihilation in flight of relativistic positrons. The total yield was sorted by the neutron multiplicity, taking into account the difference in the neutron energy spectra for different multiplicity. The two quoted studies differ in the method of determining the neutron. Significant systematic disagreements between the results of the two experiments exist. They are considered to be caused by large systematic uncertainties in partial cross sections, since they do not satisfy physical criteria for reliability of the data. To obtain reliable cross sections of partial and total photoneutron reactions a new method combining experimental data and theoretical evaluation was used. It is based on the experimental neutron yield cross section which is rather independent of neutron multiplicity and the transitional neutron multiplicity functions of the combined photonucleon reaction model (CPNRM). The model transitional multiplicity functions were used for the decomposition of the neutron yield cross section into the contributions of partial reactions. The results of the new evaluation noticeably differ from the partial cross sections obtained in the two experimental studies are under discussion. (orig.)

  4. Contacting of authors by systematic reviewers: protocol for a cross-sectional study and a survey.

    Science.gov (United States)

    Meursinge Reynders, Reint; Ladu, Luisa; Di Girolamo, Nicola

    2017-12-08

    Synthesizing outcomes of underreported primary studies can pose a serious threat to the validity of outcomes and conclusions of systematic reviews. To address this problem, the Cochrane Collaboration recommends reviewers to contact authors of eligible primary studies to obtain additional information on poorly reported items. In this protocol, we present a cross-sectional study and a survey to assess (1) how reviewers of new Cochrane intervention reviews report on procedures and outcomes of contacting of authors of primary studies to obtain additional data, (2) how authors reply, and (3) the consequences of these additional data on the outcomes and quality scores in the review. All research questions and methods were pilot tested on 2 months of Cochrane reviews and were subsequently fine-tuned. Eligibility criteria are (1) all new (not-updates) Cochrane intervention reviews published in 2016, (2) reviews that included one or more primary studies, and (3) eligible interventions refer to contacting of authors of the eligible primary studies included in the review to obtain additional research data (e.g., information on unreported or missing data, individual patient data, research methods, and bias issues). Searching for eligible reviews and data extraction will be conducted by two authors independently. The cross-sectional study will primarily focus on how contacting of authors is conducted and reported, how contacted authors reply, and how reviewers report on obtained additional data and their consequences for the review. The same eligible reviews for the cross-sectional study will also be eligible for the survey. Surveys will be sent to the contact addresses of these reviews according to a pre-defined protocol. We will use Google Forms as our survey platform. Surveyees are asked to answer eight questions. The survey will primarily focus on the consequences of contacting authors of eligible primary studies for the risk of bias and Grading of Recommendations

  5. The contribution of databases to the results of systematic reviews: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Lisa Hartling

    2016-09-01

    Full Text Available Abstract Background One of the best sources for high quality information about healthcare interventions is a systematic review. A well-conducted systematic review includes a comprehensive literature search. There is limited empiric evidence to guide the extent of searching, in particular the number of electronic databases that should be searched. We conducted a cross-sectional quantitative analysis to examine the potential impact of selective database searching on results of meta-analyses. Methods Our sample included systematic reviews (SRs with at least one meta-analysis from three Cochrane Review Groups: Acute Respiratory Infections (ARI, Infectious Diseases (ID, Developmental Psychosocial and Learning Problems (DPLP (n = 129. Outcomes included: 1 proportion of relevant studies indexed in each of 10 databases; and 2 changes in results and statistical significance of primary meta-analysis for studies identified in Medline only and in Medline plus each of the other databases. Results Due to variation across topics, we present results by group (ARI n = 57, ID n = 38, DPLP n = 34. For ARI, identification of relevant studies was highest for Medline (85 % and Embase (80 %. Restricting meta-analyses to trials that appeared in Medline + Embase yielded fewest changes in statistical significance: 53/55 meta-analyses showed no change. Point estimates changed in 12 cases; in 7 the change was less than 20 %. For ID, yield was highest for Medline (92 %, Embase (81 %, and BIOSIS (67 %. Restricting meta-analyses to trials that appeared in Medline + BIOSIS yielded fewest changes with 1 meta-analysis changing in statistical significance. Point estimates changed in 8 of 31 meta-analyses; change less than 20 % in all cases. For DPLP, identification of relevant studies was highest for Medline (75 % and Embase (62 %. Restricting meta-analyses to trials that appeared in Medline + PsycINFO resulted in only one change in

  6. Systematic reviews: a cross-sectional study of location and citation counts

    Directory of Open Access Journals (Sweden)

    Morgan Douglas

    2003-11-01

    Full Text Available Abstract Background Systematic reviews summarize all pertinent evidence on a defined health question. They help clinical scientists to direct their research and clinicians to keep updated. Our objective was to determine the extent to which systematic reviews are clustered in a large collection of clinical journals and whether review type (narrative or systematic affects citation counts. Methods We used hand searches of 170 clinical journals in the fields of general internal medicine, primary medical care, nursing, and mental health to identify review articles (year 2000. We defined 'review' as any full text article that was bannered as a review, overview, or meta-analysis in the title or in a section heading, or that indicated in the text that the intention of the authors was to review or summarize the literature on a particular topic. We obtained citation counts for review articles in the five journals that published the most systematic reviews. Results 11% of the journals concentrated 80% of all systematic reviews. Impact factors were weakly correlated with the publication of systematic reviews (R2 = 0.075, P = 0.0035. There were more citations for systematic reviews (median 26.5, IQR 12 – 56.5 than for narrative reviews (8, 20, P Conclusions A few clinical journals published most systematic reviews. Authors cited systematic reviews more often than narrative reviews, an indirect endorsement of the 'hierarchy of evidence'.

  7. Epidemiology and Reporting Characteristics of Systematic Reviews of Biomedical Research: A Cross-Sectional Study.

    Directory of Open Access Journals (Sweden)

    Matthew J Page

    2016-05-01

    Full Text Available Systematic reviews (SRs can help decision makers interpret the deluge of published biomedical literature. However, a SR may be of limited use if the methods used to conduct the SR are flawed, and reporting of the SR is incomplete. To our knowledge, since 2004 there has been no cross-sectional study of the prevalence, focus, and completeness of reporting of SRs across different specialties. Therefore, the aim of our study was to investigate the epidemiological and reporting characteristics of a more recent cross-section of SRs.We searched MEDLINE to identify potentially eligible SRs indexed during the month of February 2014. Citations were screened using prespecified eligibility criteria. Epidemiological and reporting characteristics of a random sample of 300 SRs were extracted by one reviewer, with a 10% sample extracted in duplicate. We compared characteristics of Cochrane versus non-Cochrane reviews, and the 2014 sample of SRs versus a 2004 sample of SRs. We identified 682 SRs, suggesting that more than 8,000 SRs are being indexed in MEDLINE annually, corresponding to a 3-fold increase over the last decade. The majority of SRs addressed a therapeutic question and were conducted by authors based in China, the UK, or the US; they included a median of 15 studies involving 2,072 participants. Meta-analysis was performed in 63% of SRs, mostly using standard pairwise methods. Study risk of bias/quality assessment was performed in 70% of SRs but was rarely incorporated into the analysis (16%. Few SRs (7% searched sources of unpublished data, and the risk of publication bias was considered in less than half of SRs. Reporting quality was highly variable; at least a third of SRs did not report use of a SR protocol, eligibility criteria relating to publication status, years of coverage of the search, a full Boolean search logic for at least one database, methods for data extraction, methods for study risk of bias assessment, a primary outcome, an

  8. Systematic determination of absolute absorption cross-section of individual carbon nanotubes.

    Science.gov (United States)

    Liu, Kaihui; Hong, Xiaoping; Choi, Sangkook; Jin, Chenhao; Capaz, Rodrigo B; Kim, Jihoon; Wang, Wenlong; Bai, Xuedong; Louie, Steven G; Wang, Enge; Wang, Feng

    2014-05-27

    Optical absorption is the most fundamental optical property characterizing light-matter interactions in materials and can be most readily compared with theoretical predictions. However, determination of optical absorption cross-section of individual nanostructures is experimentally challenging due to the small extinction signal using conventional transmission measurements. Recently, dramatic increase of optical contrast from individual carbon nanotubes has been successfully achieved with a polarization-based homodyne microscope, where the scattered light wave from the nanostructure interferes with the optimized reference signal (the reflected/transmitted light). Here we demonstrate high-sensitivity absorption spectroscopy for individual single-walled carbon nanotubes by combining the polarization-based homodyne technique with broadband supercontinuum excitation in transmission configuration. To our knowledge, this is the first time that high-throughput and quantitative determination of nanotube absorption cross-section over broad spectral range at the single-tube level was performed for more than 50 individual chirality-defined single-walled nanotubes. Our data reveal chirality-dependent behaviors of exciton resonances in carbon nanotubes, where the exciton oscillator strength exhibits a universal scaling law with the nanotube diameter and the transition order. The exciton linewidth (characterizing the exciton lifetime) varies strongly in different nanotubes, and on average it increases linearly with the transition energy. In addition, we establish an empirical formula by extrapolating our data to predict the absorption cross-section spectrum for any given nanotube. The quantitative information of absorption cross-section in a broad spectral range and all nanotube species not only provides new insight into the unique photophysics in one-dimensional carbon nanotubes, but also enables absolute determination of optical quantum efficiencies in important

  9. FEMA DFIRM Cross Sections

    Data.gov (United States)

    Minnesota Department of Natural Resources — FEMA Cross Sections are required for any Digital Flood Insurance Rate Map database where cross sections are shown on the Flood Insurance Rate Map (FIRM). Normally...

  10. Neutron cross sections

    CERN Document Server

    Hughes, Donald J; Dunworth, J V

    1957-01-01

    Neutron Cross Sections presents the principles of cross-section measurement and use, as well as sufficient theory so that the general behavior of cross sections is made understandable. This compilation is a direct result of experiences connected with the collection and evaluation of cross-section data during the past eight years at """"Sigma Centre"""", Brookhaven National Laboratory. Here, experimental results received from laboratories throughout the world are carefully evaluated and compiled in the curves and tables of the large volume Neutron Cross Sections, The most recent version of the

  11. Systematics of neutron-induced fission cross sections over the energy range 0.1 through 15 MeV, and at 0.0253 eV

    International Nuclear Information System (INIS)

    Behrens, J.W.

    1977-01-01

    Recent studies have shown straightforward systematic behavior as a function of constant proton and neutron number for neutron-induced fission cross sections of the actinide elements in the incident-neutron energy range 3 to 5 MeV. In this report, the second in a series, fission cross-section values are studied over the MeV incident-neutron energy range, and at 0.0253 eV. Fission-barrier heights and neutron-binding energies are correlated by constant proton and neutron number; however, these systematic behaviors alone do not explain the trends observed in the fission cross-section values

  12. Training practitioners in preparing systematic reviews: a cross-sectional survey of participants in the Australasian Cochrane Centre training program

    Directory of Open Access Journals (Sweden)

    Silagy Chris

    2002-06-01

    Full Text Available Abstract Background Although systematic reviews of health care interventions are an invaluable tool for health care providers and researchers, many potential authors never publish reviews. This study attempts to determine why some people with interest in performing systematic reviews do not subsequently publish a review; and what steps could possibly increase review completion. Methods Cross-sectional survey by email and facsimile of the 179 participants in Australasian Cochrane Centre training events between 1998 and 2000. Results Ninety-two participants responded to the survey (51 percent. Response rate of deliverable surveys was 82 percent (92/112. The remainder of the participants had invalid or no contact information on file. More than 75 percent of respondents felt that the current workshops met their needs for training. The most critical barriers to completion of a Cochrane review were: lack of time (80 percent, lack of financial support (36 percent, methodological problems (23 percent and problems with group dynamics (10 percent. Conclusions Strategies to protect reviewer time and increase the efficiency of the review process may increase the numbers of trained reviewers completing a systematic review.

  13. Contacting of authors by systematic reviewers: protocol for a cross-sectional study and a survey

    NARCIS (Netherlands)

    Meursinge Reynders, Reint; Ladu, Luisa; Di Girolamo, Nicola

    2017-01-01

    Synthesizing outcomes of underreported primary studies can pose a serious threat to the validity of outcomes and conclusions of systematic reviews. To address this problem, the Cochrane Collaboration recommends reviewers to contact authors of eligible primary studies to obtain additional information

  14. Contacting of authors by systematic reviewers: protocol for a cross-sectional study and a survey

    NARCIS (Netherlands)

    Meursinge Reynders, R.; Ladu, L.; Di Girolamo, N.

    2017-01-01

    BACKGROUND: Synthesizing outcomes of underreported primary studies can pose a serious threat to the validity of outcomes and conclusions of systematic reviews. To address this problem, the Cochrane Collaboration recommends reviewers to contact authors of eligible primary studies to obtain additional

  15. Mesenteric panniculitis: systematic review of cross-sectional imaging findings and risk of subsequent malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Halligan, Steve; Plumb, Andrew; Taylor, Stuart [University College London UCL, Centre for Medical Imaging, 3rd Floor East, London (United Kingdom)

    2016-12-15

    Systematic review to determine any association between imaging features of idiopathic mesenteric panniculitis (MP) and subsequent malignancy. Two researchers searched primary literature independently for imaging studies of MP. They extracted data focusing on methodology for unbiased patient accrual and capability to determine a link between MP and subsequent malignancy. They noted imaging features of MP. Data were accrued and meta-analysis intended. Fourteen of 675 articles were eligible; 1,226 patients. Only three (21 %) accrued patients prospectively. Twelve (86 %) studies described CT features. Follow-up varied widely; 1 month to 8 years. Prevalence of MP was influenced by accrual: 0.2 % for keyword search versus 1.7 % for consecutive series. Accrual bias affected nine (64 %) studies. 458 (38 %) of 1,209 patients had malignancy at accrual but varied widely (8-89 %), preventing meta-analysis. Sixty (6.4 %) of 933 patients developed new malignancy subsequently, also varying widely (0-11 %). Of just four studies that determined the proportion of unselected, consecutive patients with MP developing subsequent malignancy, three were retrospective and the fourth excluded patients with lymphadenopathy, likely excluding patients with MP. Studies were heterogeneous, with biased accrual. No available study can determine an association between MP and subsequent malignancy with certainty. (orig.)

  16. Floodplain Cross Section Lines

    Data.gov (United States)

    Department of Homeland Security — This table is required for any Digital Flood Insurance Rate Map database where cross sections are shown on the Flood Insurance Rate Map (FIRM). Normally any FIRM...

  17. How do authors of systematic reviews deal with research malpractice and misconduct in original studies? A cross-sectional analysis of systematic reviews and survey of their authors.

    Science.gov (United States)

    Elia, Nadia; von Elm, Erik; Chatagner, Alexandra; Pöpping, Daniel M; Tramèr, Martin R

    2016-03-02

    To study whether systematic reviewers apply procedures to counter-balance some common forms of research malpractice such as not publishing completed research, duplicate publications, or selective reporting of outcomes, and to see whether they identify and report misconduct. Cross-sectional analysis of systematic reviews and survey of their authors. 118 systematic reviews published in four journals (Ann Int Med, BMJ, JAMA, Lancet), and the Cochrane Library, in 2013. Number (%) of reviews that applied procedures to reduce the impact of: (1) publication bias (through searching of unpublished trials), (2) selective outcome reporting (by contacting the authors of the original studies), (3) duplicate publications, (4) sponsors' and (5) authors' conflicts of interest, on the conclusions of the review, and (6) looked for ethical approval of the studies. Number (%) of reviewers who suspected misconduct are reported. The procedures applied were compared across journals. 80 (68%) reviewers confirmed their data. 59 (50%) reviews applied three or more procedures; 11 (9%) applied none. Unpublished trials were searched in 79 (66%) reviews. Authors of original studies were contacted in 73 (62%). Duplicate publications were searched in 81 (69%). 27 reviews (23%) reported sponsors of the included studies; 6 (5%) analysed their impact on the conclusions of the review. Five reviews (4%) looked at conflicts of interest of study authors; none of them analysed their impact. Three reviews (2.5%) looked at ethical approval of the studies. Seven reviews (6%) suspected misconduct; only 2 (2%) reported it explicitly. Procedures applied differed across the journals. Only half of the systematic reviews applied three or more of the six procedures examined. Sponsors, conflicts of interest of authors and ethical approval remain overlooked. Research misconduct is sometimes identified, but rarely reported. Guidance on when, and how, to report suspected misconduct is needed. Published by the BMJ

  18. A systematics of optical model compound nucleus formation cross sections for neutrons, proton, deuteron, 3He and alpha particle incidents

    International Nuclear Information System (INIS)

    Murata, Toru

    2000-01-01

    Simple formulae to reproduce the optical model compound nucleus formation cross sections for neutron, proton, deuteron, triton, 3 He and alpha particles are presented for target nuclei of light to medium weight mass region. (author)

  19. Measurements and systematics studies of the (n,p), (n,α) and (n,2n) reactions cross-sections at 14.5 MeV neutrons

    International Nuclear Information System (INIS)

    Osman, Khalda

    2000-01-01

    Accurate knowledge of the cross-sections for fast neutron-induced reactions utilizing the D-T reaction is important not only because of the wide spread of data observed in the literature, but also because of the world wide demand and requests for such data, in view of the increasing interest in the fusion reactor technology, which is based on the same reactions. Cross-sections are needed also for various practical purposes, including neutron activation analysis and dosimetry. In this work the (n.p), (n,2n) and (n,α) reactions cross-sections were measured at 14.5 MeV for isotopes of the elements: Cr, Ti, Ni, Co, Zr, and Mo using the activation method. The measured cross-sections were compared with recently published data. Good agreement was observed for most of the measurements. The discrepancies observed were attributed to difficulties related to the long half-life of the product nuclei and small abundances of the target isotopes. Attempts were also made to study the dependence of the (n,p), (n,2n) and (n,α) reactions cross-sections on the on the asymmetry parameter (N-Z)/A. The results confirmed the trend theoretically suggested by Levkovskii and experimentally realized by Qaim and co-workers. The isotopic dependence of (n,p) reaction cross-sections and the variation of the ration σ n ,p/σ n ,α with Z-number of the target isotopes were also studied in this work and the results obtained were found to be in agreement with theoretical predictions. In this work studies carried out for the systematics of the (n,p), (n,2n) and (n,α) reactions cross-sections at 14 MeV neutrons and formula based on the statistical model presented, with the aim of improving the systematics of these cross-sections. Comparison of present proposed systematics were for the (n,p), (n,2n) and (n,α) reactions cross-sections with the cross-section values measured in this work was made. Good agreement was generally noted, but some discrepancies were also observed. These discrepancies were

  20. SUSY Production cross sections.

    Energy Technology Data Exchange (ETDEWEB)

    Berger, E. L.; Harris, B.; Klasen, M.; Tait, T.

    1999-03-19

    We summarize the status of next-to-leading order perturbative quantum chromodynamics (pQCD) calculations of the cross sections for the production of squarks, gluinos, neutralinos, charginos, and sleptons as a function of the produced particle masses in proton-antiproton collisions at the hadronic center-of-mass energy 2 TeV.

  1. Evaluation of the association between acne and smoking: systematic review and meta-analysis of cross-sectional studies

    Directory of Open Access Journals (Sweden)

    Alice Mannocci

    2010-09-01

    Full Text Available

    Background: Acne vulgaris is one of the most common skin diseases with a multifactorial pathogenesis. Examination of the literature regarding the contribution of smoking to acne shows contradictory results. The aim of this study was to undertake a systematic review of the literature and meta-analysis about the association between acne and smoking.

    Methods: A systematic review and meta-analysis, when possible were performed. The literature review was based on Pubmed, Scopus and Google Scholar searches using the keywords “(smoking OR tobacco OR nicotine OR cigarettes AND acne”. Only cross-sectional studies were included. Meta-analyses were performed using the RevMan software version 5 for Windows. Four different meta-analyses were carried out: one evaluating the association between smoking habit and acne, one including data stratified by gender, one for studies with a quality score > 6, and one relating to acne classification.

    Results: Six studies were selected. The first meta-analysis, including all studies, showed a non significant role of smoke in the development of acne: OR 1.05 (95% CI: 0.66–1.67 with random effect estimate. The second meta-analyses, including data stratified by gender, showed a OR=0.99 (95% CI: 0.57–1.73 for males and a OR of 1.45 (95% CI: 0.08–24.64 for females, using random effect for the heterogeneity in both cases. The third meta-analysis, included studies with a quality score >6 resulted in an estimated OR= 0.69 (95% CI: 0.55–0.85: in this case it was possible to use the fixed effect estimate. The last meta-analysis, concerning the severity grading, showed a non-significant result: OR=1.09 (95% CI: 0.61–1.95 using the random effect approach.

    Conclusions: The first two meta-analyses found no signification association between smoking and

  2. Radar cross section

    CERN Document Server

    Knott, Gene; Tuley, Michael

    2004-01-01

    This is the second edition of the first and foremost book on this subject for self-study, training, and course work. Radar cross section (RCS) is a comparison of two radar signal strengths. One is the strength of the radar beam sweeping over a target, the other is the strength of the reflected echo sensed by the receiver. This book shows how the RCS ?gauge? can be predicted for theoretical objects and how it can be measured for real targets. Predicting RCS is not easy, even for simple objects like spheres or cylinders, but this book explains the two ?exact? forms of theory so well that even a

  3. Systematic study of three-nucleon force effects in the cross section of the deuteron-proton breakup at 130 MeV

    International Nuclear Information System (INIS)

    St. Kistryn; E. Stephan; A. Biegun; K. Bodek; A. Deltuva; E. Epelbaum; K. Ermisch; W. Gloeckle; J. Golak; N. Kalantar-Nayestanaki; H. Kamada; M. Kis; B. Klos; A. Kozela; J. Kuros-Zolnierczuk; M. Mahjour-Shafiei; U.-G. Meissner; A. Micherdzinska; A. Nogga; P. U. Sauer; R. Skibinski; R. Sworst; H. Witala; J. Zejma; W. Zipper

    2005-01-01

    High precision cross-section data of the deuteron-proton breakup reaction at 130 MeV are presented for 72 kinematically complete configurations. The data cover a large region of the available phase space, divided into a systematic grid of kinematical variables. They are compared with theoretical predictions, in which the full dynamics of the three-nucleon (3N) system is obtained in three different ways: realistic nucleon-nucleon (NN) potentials are combined with model 3N forces (3NF's) or with an effective 3NF resulting from explicit treatment of the Delta-isobar excitation. Alternatively, the chiral perturbation theory approach is used at the next-to-next-to-leading order with all relevant NN and 3N contributions taken into account. The generated dynamics is then applied to calculate cross-section values by rigorous solution of the 3N Faddeev equations. The comparison of the calculated cross sections with the experimental data shows a clear preference for the predictions in which the 3NF's are included. The majority of the experimental data points is well reproduced by the theoretical predictions. The remaining discrepancies are investigated by inspecting cross sections integrated over certain kinematical variables. The procedure of global comparisons leads to establishing regularities in disagreements between the experimental data and the theoretically predicted values of the cross sections. They indicate deficiencies still present in the assumed models of the 3N system dynamics

  4. Fast, accurate photon beam accelerator modeling using BEAMnrc: A systematic investigation of efficiency enhancing methods and cross-section data

    Energy Technology Data Exchange (ETDEWEB)

    Fragoso, Margarida; Kawrakow, Iwan; Faddegon, Bruce A.; Solberg, Timothy D.; Chetty, Indrin J. [Henry Ford Health System, Detroit, Michigan 48202 (United States); National Research Council of Canada, Ottawa, Ontario K1A OR6 (Canada); University of California, San Francisco, California 94143-0226 (United States); UT Southwestern Medical Center, Dallas, Texas 75390-9183 (United States); Henry Ford Health System, Detroit, Michigan 48202 (United States)

    2009-12-15

    In this work, an investigation of efficiency enhancing methods and cross-section data in the BEAMnrc Monte Carlo (MC) code system is presented. Additionally, BEAMnrc was compared with VMC++, another special-purpose MC code system that has recently been enhanced for the simulation of the entire treatment head. BEAMnrc and VMC++ were used to simulate a 6 MV photon beam from a Siemens Primus linear accelerator (linac) and phase space (PHSP) files were generated at 100 cm source-to-surface distance for the 10x10 and 40x40 cm{sup 2} field sizes. The BEAMnrc parameters/techniques under investigation were grouped by (i) photon and bremsstrahlung cross sections, (ii) approximate efficiency improving techniques (AEITs), (iii) variance reduction techniques (VRTs), and (iv) a VRT (bremsstrahlung photon splitting) in combination with an AEIT (charged particle range rejection). The BEAMnrc PHSP file obtained without the efficiency enhancing techniques under study or, when not possible, with their default values (e.g., EXACT algorithm for the boundary crossing algorithm) and with the default cross-section data (PEGS4 and Bethe-Heitler) was used as the ''base line'' for accuracy verification of the PHSP files generated from the different groups described previously. Subsequently, a selection of the PHSP files was used as input for DOSXYZnrc-based water phantom dose calculations, which were verified against measurements. The performance of the different VRTs and AEITs available in BEAMnrc and of VMC++ was specified by the relative efficiency, i.e., by the efficiency of the MC simulation relative to that of the BEAMnrc base-line calculation. The highest relative efficiencies were {approx}935 ({approx}111 min on a single 2.6 GHz processor) and {approx}200 ({approx}45 min on a single processor) for the 10x10 field size with 50 million histories and 40x40 cm{sup 2} field size with 100 million histories, respectively, using the VRT directional bremsstrahlung

  5. Microscopic cross sections: An utopia?

    Energy Technology Data Exchange (ETDEWEB)

    Hilaire, S. [CEA Bruyeres-le-Chatel, DIF 91 (France); Koning, A.J. [Nuclear Research and Consultancy Group, PO Box 25, 1755 ZG Petten (Netherlands); Goriely, S. [Institut d' Astronomie et d' Astrophysique, Universite Libre de Bruxelles, Campus de la Plaine, CP 226, 1050 Brussels (Belgium)

    2010-07-01

    The increasing need for cross sections far from the valley of stability poses a challenge for nuclear reaction models. So far, predictions of cross sections have relied on more or less phenomenological approaches, depending on parameters adjusted to available experimental data or deduced from systematical relations. While such predictions are expected to be reliable for nuclei not too far from the experimentally known regions, it is clearly preferable to use more fundamental approaches, based on sound physical bases, when dealing with very exotic nuclei. Thanks to the high computer power available today, all major ingredients required to model a nuclear reaction can now be (and have been) microscopically (or semi-microscopically) determined starting from the information provided by a nucleon-nucleon effective interaction. We have implemented all these microscopic ingredients in the TALYS nuclear reaction code, and we are now almost able to perform fully microscopic cross section calculations. The quality of these ingredients and the impact of using them instead of the usually adopted phenomenological parameters will be discussed. (authors)

  6. Microscopic cross sections: An utopia?

    International Nuclear Information System (INIS)

    Hilaire, S.; Koning, A.J.; Goriely, S.

    2010-01-01

    The increasing need for cross sections far from the valley of stability poses a challenge for nuclear reaction models. So far, predictions of cross sections have relied on more or less phenomenological approaches, depending on parameters adjusted to available experimental data or deduced from systematical relations.While such predictions are expected to be reliable for nuclei not too far from the experimentally known regions, it is clearly preferable to use more fundamental approaches, based on sound physical bases, when dealing with very exotic nuclei. Thanks to the high computer power available today, all major ingredients required to model a nuclear reaction can now be (and have been) microscopically (or semi-microscopically) determined starting from the information provided by a nucleon-nucleon effective interaction. We have implemented all these microscopic ingredients in the TALYS nuclear reaction code, and we are now almost able to perform fully microscopic cross section calculations. The quality of these ingredients and the impact of using them instead of the usually adopted phenomenological parameters will be discussed. (authors)

  7. Systematic study of (n, p) reaction cross sections from the reaction threshold to 20 MeV

    NARCIS (Netherlands)

    Lalremruata, B.; Otuka, N.; Tambave, G. J.; Mulik, V. K.; Patil, B. J.; Dhole, S. D.; Saxena, A.; Ganesan, S.; Bhoraskar, V. N.

    2012-01-01

    The cross sections of Cr-nat(n, x)V-52, Cr-52(n, p)V-52, Cr-nat(n, x)V-53, Cr-53(n, p)V-53, Zn-nat(n, x)Cu-66, Zn-66(n, p)Cu-66, Zn-nat(n, x)Cu-68(m), Zn-68(n, p)Cu-68(m), Mo-nat(n, x)Nb-97(g), Mo-97(n, p)Nb-97(g), Mo-nat(n, x)Nb-97(m), Mo-97(n, p)Nb-97(m), Sn-nat(n, x)In-116(m1+m2), Sn-116(n,

  8. The tbar-t cross-section at 1.8 and 1.96 TeV: a study of the systematics due to parton densities and scale dependence

    International Nuclear Information System (INIS)

    Cacciari, M.; Frixione, S.; Mangano, M.L.; Nason, P.; Ridolfi, G.

    2004-01-01

    We update the theoretical predictions for the tbar-t production cross-section at the Tevatron, taking into account the most recent determinations of systematic uncertainties in the extraction of the proton parton densities. (author)

  9. The t-tbar cross-section at 1.8 and 1.96 TeV a study of the systematics due to parton densities and scale dependence

    CERN Document Server

    Cacciari, M; Mangano, Michelangelo L; Nason, P; Ridolfi, G

    2004-01-01

    We update the theoretical predictions for the t-tbar production cross-section at the Tevatron, taking into account the most recent determinations of systematic uncertainties in the extraction of the proton parton densities.

  10. Factors influencing citations to systematic reviews in skin diseases: a cross-sectional study through Web of Sciences and Scopus.

    Science.gov (United States)

    Manriquez, Juan; Cataldo, Karina; Harz, Isidora

    2015-01-01

    Disseminating information derived from systematic reviews is a fundamental step for translating evidence into practice. To determine which features of dermatological SR are associated with systematic review dissemination, using citation rates as an indicator. Dermatological systematic reviews published between 2008 and 2012 were obtained from Scopus, the ISI Web of Sciences and the Cochrane Skin Group. Bibliometric data of every systematic review were collected and analyzed. A total of 320 systematic reviews were analyzed. Univariable analysis showed that the journal impact factor, number of authors, and total references cited were positively associated with the number of citations. There was a significant difference in the median number of citations with regard to the corresponding author's country, type of skin disease, type of funding, and presence of international collaboration. Cochrane reviews were significantly associated with a lower number of citations. Multivariable analysis found that the number of authors, number of references cited and the corresponding author from United Kingdom were independently correlated with many citations. Cochrane systematic reviews tended to be independently associated with a lower number of citations. Citation number to systematic reviews may be improving by increasing the number of authors, especially collaborative authors, and the number of cited references. The reasons for the association of Cochrane SRs with fewer citations should be addressed in future studies.

  11. Factors influencing citations to systematic reviews in skin diseases: a cross-sectional study through Web of Sciences and Scopus*

    Science.gov (United States)

    Manriquez, Juan; Cataldo, Karina; Harz, Isidora

    2015-01-01

    BACKGROUND Disseminating information derived from systematic reviews is a fundamental step for translating evidence into practice. OBJECTIVE To determine which features of dermatological SR are associated with systematic review dissemination, using citation rates as an indicator. METHODS Dermatological systematic reviews published between 2008 and 2012 were obtained from Scopus, the ISI Web of Sciences and the Cochrane Skin Group. Bibliometric data of every systematic review were collected and analyzed. RESULTS A total of 320 systematic reviews were analyzed. Univariable analysis showed that the journal impact factor, number of authors, and total references cited were positively associated with the number of citations. There was a significant difference in the median number of citations with regard to the corresponding author's country, type of skin disease, type of funding, and presence of international collaboration. Cochrane reviews were significantly associated with a lower number of citations. Multivariable analysis found that the number of authors, number of references cited and the corresponding author from United Kingdom were independently correlated with many citations. Cochrane systematic reviews tended to be independently associated with a lower number of citations. CONCLUSIONS Citation number to systematic reviews may be improving by increasing the number of authors, especially collaborative authors, and the number of cited references. The reasons for the association of Cochrane SRs with fewer citations should be addressed in future studies. PMID:26560209

  12. Is the information of systematic reviews published in nursing journals up-to-date? a cross-sectional study.

    Science.gov (United States)

    Tam, Wilson W S; Lo, Kenneth K H; Khalechelvam, Parames; Seah, Joey; Goh, Shawn Y S

    2017-11-25

    An up-to-date systematic review is important for researchers to decide whether to embark on new research or continue supporting ongoing studies. The aim of this study is to examine the time taken between the last search, submission, acceptance and publication dates of systematic reviews published in nursing journals. Nursing journals indexed in Journal Citation Reports were first identified. Thereafter, systematic reviews published in these journals in 2014 were extracted from three databases. The quality of the systematic reviews were evaluated by the AMSTAR. The last search, submission, acceptance, online publication, full publication dates and other characteristics of the systematic reviews were recorded. The time taken between the five dates was then computed. Descriptive statistics were used to summarize the time differences; non-parametric statistics were used to examine the association between the time taken from the last search and full publication alongside other potential factors, including the funding support, submission during holiday periods, number of records retrieved from database, inclusion of meta-analysis, and quality of the review. A total of 107 nursing journals were included in this study, from which 1070 articles were identified through the database search. After screening for eligibility, 202 systematic reviews were included in the analysis. The quality of these reviews was low with the median score of 3 out of 11. A total of 172 (85.1%), 72 (35.6%), 153 (75.7%) and 149 (73.8%) systematic reviews provided their last search, submission, acceptance and online published dates respectively. The median numbers of days taken from the last search to acceptance and to full publication were, respectively, 393 (IQR: 212-609) and 669 (427-915) whereas that from submission to full publication was 365 (243-486). Moreover, the median number of days from the last search to submission and from submission to online publication were 167.5 (53.5-427) and 153

  13. Value of systematic detection of physical child abuse at emergency rooms: a cross-sectional diagnostic accuracy study.

    Science.gov (United States)

    Sittig, Judith S; Uiterwaal, Cuno S P M; Moons, Karel G M; Russel, Ingrid M B; Nievelstein, Rutger A J; Nieuwenhuis, Edward E S; van de Putte, Elise M

    2016-03-22

    The aim of our diagnostic accuracy study Child Abuse Inventory at Emergency Rooms (CHAIN-ER) was to establish whether a widely used checklist accurately detects or excludes physical abuse among children presenting to ERs with physical injury. A large multicentre study with a 6-month follow-up. 4 ERs in The Netherlands. 4290 children aged 0-7 years attending the ER because of physical injury. All children were systematically tested with an easy-to-use child abuse checklist (index test). A national expert panel (reference standard) retrospectively assessed all children with positive screens and a 15% random sample of the children with negative screens for physical abuse, using additional information, namely, an injury history taken by a paediatrician, information provided by the general practitioner, youth doctor and social services by structured questionnaires, and 6-month follow-up information. Physical child abuse. Injury due to neglect and need for help. 4253/4290 (99%) parents agreed to follow-up. At a prevalence of 0.07% (3/4253) for inflicted injury by expert panel decision, the positive predictive value of the checklist was 0.03 (95% CI 0.006 to 0.085), and the negative predictive value 1.0 (0.994 to 1.0). There was 100% (93 to 100) agreement about inflicted injury in children, with positive screens between the expert panel and child abuse experts. Rare cases of inflicted injury among preschool children presenting at ERs for injury are very likely captured by easy-to-use checklists, but at very high false-positive rates. Subsequent assessment by child abuse experts can be safely restricted to children with positive screens at very low risk of missing cases of inflicted injury. Because of the high false positive rate, we do advise careful prior consideration of cost-effectiveness and clinical and societal implications before de novo implementation. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence

  14. The cross-sectional associations between objectively measured sedentary time and cardiometabolic health markers in adults - a systematic review with meta-analysis component.

    Science.gov (United States)

    Powell, C; Herring, M P; Dowd, K P; Donnelly, A E; Carson, B P

    2018-03-01

    Sedentary time is viewed as an independent risk factor for adverse cardiometabolic health (CMH). No systematic review and meta-analysis on the cross-sectional associations between objectively measured sedentary time and CMH markers has been conducted. PubMed, Scopus and Web of Science Core Collection were searched for papers that examined the cross-sectional association between objectively measured sedentary time and CMH markers in adults. Forty-six papers met the inclusion criteria. The included papers had a combined sample size of 70,576 and an age range of 18-87 years. To examine the effect of increased levels of sedentary time on CMH markers, data on effect sizes and moderators were extracted, where possible. By pooling the unadjusted data from the included papers, increased sedentary time was shown to have a significant detrimental association with fasting glucose (Δ = 0.12, 95% confidence interval [CI]: 0.02, 0.23), fasting insulin (Δ = 0.19, 95% CI: 0.06, 0.32), triglycerides (Δ = 0.25, 95% CI: 0.14, 0.37), high-density lipoprotein cholesterol (Δ = -0.20, 95% CI: -0.28, -0.13) and waist circumference (Δ = 0.25, 95% CI: 0.15, 0.35). How sedentary time was quantified and the device used to measure sedentary time significantly influence the size of the effect reported. Future interventions focused on both decreasing sedentary time and increasing physical activity may be the most effective strategy to improve CMH. © 2017 World Obesity Federation.

  15. Differential cross section of He

    Indian Academy of Sciences (India)

    Angular distribution; differential cross section; electronic excitation; ionization of molecules. PACS Nos 34.50.Fa; 34.80.Dp. 1. Introduction. It is well known that ... proper accounting of electron–electron correlation in the final state, there are complica- tions due to the multi-electron structure of the target and the residual ion.

  16. Endorsement of PRISMA statement and quality of systematic reviews and meta-analyses published in nursing journals: a cross-sectional study.

    Science.gov (United States)

    Tam, Wilson W S; Lo, Kenneth K H; Khalechelvam, Parames

    2017-02-07

    Systematic reviews (SRs) often poorly report key information, thereby diminishing their usefulness. Previous studies evaluated published SRs and determined that they failed to meet explicit criteria or characteristics. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement was recommended as a reporting guideline for SR and meta-analysis (MA), but previous studies showed that adherence to the statement was not high for SRs published in different medical fields. Thus, the aims of this study are twofold: (1) to investigate the number of nursing journals that have required or recommended the use of the PRISMA statement for reporting SR, and (2) to examine the adherence of SRs and/or meta-analyses to the PRISMA statement published in nursing journals. A cross-sectional study. Nursing journals listed in the ISI journal citation report were divided into 2 groups based on the recommendation of PRISMA statement in their 'Instruction for Authors'. SRs and meta-analyses published in 2014 were searched in 3 databases. 37 SRs and meta-analyses were randomly selected in each group. The adherence of each item to the PRISMA was examined and summarised using descriptive statistics. The quality of the SRs was assessed by Assessing the Methodological Quality of Systematic Reviews. The differences between the 2 groups were compared using the Mann-Whitney U test. Out of 107 nursing journals, 30 (28.0%) recommended or required authors to follow the PRISMA statement when they submit SRs or meta-analyses. The median rates of adherence to the PRISMA statement for reviews published in journals with and without PRISMA endorsement were 64.9% (IQR: 17.6-92.3%) and 73.0% (IQR: 59.5-94.6%), respectively. No significant difference was observed in any of the items between the 2 groups. The median adherence of SRs and meta-analyses in nursing journals to PRISMA is low at 64.9% and 73.0%, respectively. Nonetheless, the adherence level of nursing journals to the

  17. Systematic effects on cross section data derived from reaction rates in reactor spectra and a re-analysis of 241Am reactor activation measurements

    Science.gov (United States)

    Žerovnik, Gašper; Schillebeeckx, Peter; Becker, Björn; Fiorito, Luca; Harada, Hideo; Kopecky, Stefan; Radulović, Vladimir; Sano, Tadafumi

    2018-01-01

    Methodologies to derive cross section data from spectrum integrated reaction rates were studied. The Westcott convention and some of its approximations were considered. Mostly measurements without and with transmission filter are combined to determine the reaction cross section at thermal energy together with the resonance integral. The accuracy of the results strongly depends on the assumptions that are made about the neutron energy distribution, which is mostly parameterised as a sum of a thermal and an epi-thermal component. Resonance integrals derived from such data can be strongly biased and should only be used in case no other data are available. The cross section at thermal energy can be biased for reaction cross sections which are dominated by low energy resonances. The amplitude of the effect is related to the lower energy limit that is used for the epi-thermal component of the neutron energy distribution. It is less affected by the assumptions on the shape of the energy distribution. When the energy dependence of the cross section is known and information about the neutron energy distribution is available, a method to correct for a bias on the cross section at thermal energy is proposed. Reactor activation measurements to determine the thermal 241Am(n, γ) cross section reported in the literature were reviewed. In case enough information was available, the results were corrected to account for possible biases and included in a least squares fit. These data combined with results of time-of-flight measurements give a capture cross section 720 (14) b for 241Am(n, γ) at thermal energy.

  18. Negative ion detachment cross sections

    International Nuclear Information System (INIS)

    Champion, R.L.; Doverspike, L.D.

    1992-10-01

    The authors have measured absolute cross sections for electron detachment and charge exchange for collision of O and S with atomic hydrogen, have investigated the sputtering and photodesorption of negative ions from gas covered surfaces, and have begun an investigation of photon-induced field emission of electrons from exotic structures. Brief descriptions of these activities as well as future plans for these projects are given below

  19. Terahertz radar cross section measurements

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd

    2010-01-01

    We perform angle- and frequency-resolved radar cross section (RCS) measurements on objects at terahertz frequencies. Our RCS measurements are performed on a scale model aircraft of size 5-10 cm in polar and azimuthal configurations, and correspond closely to RCS measurements with conventional rad...... information and also allows for identification of scattering points such as weaponry attached to the aircraft. The shapes of the models and positions of reflecting parts are retrieved by the filtered back projection algorithm....

  20. Obsessive-Compulsive Disorder and quality of life outcomes: protocol for a systematic review and meta-analysis of cross-sectional case-control studies

    Directory of Open Access Journals (Sweden)

    Anna Coluccia

    2015-06-01

    Full Text Available Background. Obsessive-compulsive Disorder (OCD is a chronic disabling psychological condition, which can severely affect quality of life (QOL. Growing interest has been dedicated to assessing which domains of QOL are more severely affected in patients with OCD. However, research yielded conflicting findings. Investigating QOL in OCD could suggest the need for integration of interventions aimed at improving those specific domains more severely impaired by obsessions and compulsions.Methods. We will conduct a systematic review of cross-sectional case-control studies according to PRISMA guidelines, where patients with a primary OCD diagnosis were compared on QOL outcomes with healthy controls. Primary objectives will be to examine differences in QOL outcomes between patients with OCD and healthy controls, and to assess which QOL domains are more severely impaired in patients compared with controls, particularly subjective well-being, social and interpersonal functioning, work functioning, and family functioning. Subsequently, the study will investigate potential moderators of QOL in OCD, including participants characteristics (age, sex, presence of comorbid personality disorders, OCD symptom severity, severity of concurrent depressive symptoms, duration of OCD symptoms, and generational cohort, and study characteristics (date of publication and methodological quality of the studies. Online databases will be searched (PsycINFO, PubMED, Science Direct, Cinahl, Biological Abstracts, Psyclit, Embase, The Cochrane Central Register of Controlled Trials, and Google Scholar. To locate unpublished records, conference abstracts, doctoral dissertations and theses will be handsearched, and experts will be contacted. Statistical analyses will be performed though random effect model meta-analysis. Risk of bias assessments will be conducted using the instrument Methodological Index for Non-Randomized Studies.

  1. Wind Turbine Radar Cross Section

    Directory of Open Access Journals (Sweden)

    David Jenn

    2012-01-01

    Full Text Available The radar cross section (RCS of a wind turbine is a figure of merit for assessing its effect on the performance of electronic systems. In this paper, the fundamental equations for estimating the wind turbine clutter signal in radar and communication systems are presented. Methods of RCS prediction are summarized, citing their advantages and disadvantages. Bistatic and monostatic RCS patterns for two wind turbine configurations, a horizontal axis three-blade design and a vertical axis helical design, are shown. The unique electromagnetic scattering features, the effect of materials, and methods of mitigating wind turbine clutter are also discussed.

  2. [Fast neutron cross section measurements

    International Nuclear Information System (INIS)

    1991-01-01

    In the 14 MeV Neutron Laboratory, we have continued the development of a facility that is now the only one of its kind in operation in the United States. We have refined the klystron bunching system described in last year's report to the point that 1.2 nanosecond pulses have been directly measured. We have tested the pulse shape discrimination capability of our primary NE 213 neutron detector. We have converted the RF sweeper section of the beamline to a frequency of 1 MHz to replace the function of the high voltage pulser described in last year's report which proved to be difficult to maintain and unreliable in its operation. We have also overcome several other significant experimental difficulties, including a major problem with a vacuum leak in the main accelerator column. We have completed additional testing to prove the remainder of the generation and measurement systems, but overcoming some of these experimental difficulties has delayed the start of actual data taking. We are now in a position to begin our first series of ring geometry elastic scattering measurements, and these will be underway before the end of the current contract year. As part of our longer term planning, we are continuing the conceptual analysis of several schemes to improve the intensity of our current pulsed beam. These include the provision of a duoplasmatron ion source and/or the provision of preacceleration bunching. Additional details are given later in this report. A series of measurements were carried out at the Tandem Dynamatron Facility involving the irradiation of a series of yttrium foils and the determination of activation cross sections using absolute counting techniques. The experimental work has been completed, and final analysis of the cross section data will be completed within several months

  3. Differential white blood cell count and type 2 diabetes: systematic review and meta-analysis of cross-sectional and prospective studies.

    Directory of Open Access Journals (Sweden)

    Effrossyni Gkrania-Klotsas

    2010-10-01

    Full Text Available Biological evidence suggests that inflammation might induce type 2 diabetes (T2D, and epidemiological studies have shown an association between higher white blood cell count (WBC and T2D. However, the association has not been systematically investigated.Studies were identified through computer-based and manual searches. Previously unreported studies were sought through correspondence. 20 studies were identified (8,647 T2D cases and 85,040 non-cases. Estimates of the association of WBC with T2D were combined using random effects meta-analysis; sources of heterogeneity as well as presence of publication bias were explored.The combined relative risk (RR comparing the top to bottom tertile of the WBC count was 1.61 (95% CI: 1.45; 1.79, p = 1.5*10(-18. Substantial heterogeneity was present (I(2 = 83%. For granulocytes the RR was 1.38 (95% CI: 1.17; 1.64, p = 1.5*10(-4, for lymphocytes 1.26 (95% CI: 1.02; 1.56, p = 0.029, and for monocytes 0.93 (95% CI: 0.68; 1.28, p = 0.67 comparing top to bottom tertile. In cross-sectional studies, RR was 1.74 (95% CI: 1.49; 2.02, p = 7.7*10(-13, while in cohort studies it was 1.48 (95% CI: 1.22; 1.79, p = 7.7*10(-5. We assessed the impact of confounding in EPIC-Norfolk study and found that the age and sex adjusted HR of 2.19 (95% CI: 1.74; 2.75 was attenuated to 1.82 (95% CI: 1.45; 2.29 after further accounting for smoking, T2D family history, physical activity, education, BMI and waist circumference.A raised WBC is associated with higher risk of T2D. The presence of publication bias and failure to control for all potential confounders in all studies means the observed association is likely an overestimate.

  4. K+ nucleus total cross sections

    International Nuclear Information System (INIS)

    Sawafta, R.

    1990-01-01

    The scattering of K + mesons from nuclei has attracted considerable interest in the last few years. The K + holds a very special position as the weakest of all strongly interaction probes. The average cross section is not larger than about 10 mb at lab momenta below 800 MeV/c, corresponding to a mean free path in the nucleus larger than 5 fm. Thus the K + is capable of probing the entire volume of the nucleus. Single scattering of the K + with a nucleon in the nucleus dominates the nuclear scattering, and only small and calculable higher order corrections are needed. The nucleon is a dynamical entity and its internal structure can, in principle, be altered by its surrounding nuclear environment. This work reports an experiment in which the K + is used to compare the nucleon in the nucleus with a free nucleon

  5. Prevalence rates of drug use among school bullies and victims: A systematic review and meta-analysis of cross-sectional studies

    OpenAIRE

    Valdebenito, Sara; Ttofi, Maria; Eisner, Manuel

    2015-01-01

    This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.avb.2015.05.004 Bullying is a common aggressive behaviour in school, with a number of cross-sectional studies showing that it exhibits a high comorbidity with other problem behaviours. The present study aims to estimate the comorbidity of school bullying (perpetration and victimisation) with drug use by incorporating and meta-analysing all available evidence on the cross-sec...

  6. Nuclear Forensics and Radiochemistry: Cross Sections

    Energy Technology Data Exchange (ETDEWEB)

    Rundberg, Robert S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-08

    The neutron activation of components in a nuclear device can provide useful signatures of weapon design or sophistication. This lecture will cover some of the basics of neutron reaction cross sections. Nuclear reactor cross sections will also be presented to illustrate the complexity of convolving neutron energy spectra with nuclear excitation functions to calculate useful effective reactor cross sections. Deficiencies in the nuclear database will be discussed along with tools available at Los Alamos to provide new neutron cross section data.

  7. Neutron cross sections: Book of curves

    International Nuclear Information System (INIS)

    McLane, V.; Dunford, C.L.; Rose, P.F.

    1988-01-01

    Neuton Cross Sections: Book of Curves represents the fourth edition of what was previously known as BNL-325, Neutron Cross Sections, Volume 2, CURVES. Data is presented only for (i.e., intergrated) reaction cross sections (and related fission parameters) as a function of incident-neutron energy for the energy range 0.01 eV to 200 MeV. For the first time, isometric state production cross sections have been included. 11 refs., 4 figs

  8. ASCAP. Resonance Region Cross Section Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.R.; Young, R.C. [EG and G Idaho Inc., Idaho Falls, ID (United States)

    1972-09-01

    ACSAP may be used to compute neutron cross section data from neutron resonance input. Total, fission, capture, or scattering cross section data may be computed. Experimental data may be compared by means of a wide selection of representations. ACSAP can also determine cross section resonance parameters from input experimental data.

  9. Integral nucleus-nucleus cross sections

    International Nuclear Information System (INIS)

    Barashenkov, V.S.; Kumawat, H.

    2003-01-01

    Expressions approximating the experimental integral cross sections for elastic and inelastic interactions of light and heavy nuclei at the energies up to several GeV/nucleon are presented. The calculated cross sections are inside the corridor of experimental errors or very close to it. Described in detail FORTRAN code and a numerical example of the cross section approximation are also presented

  10. SNL RML recommended dosimetry cross section compendium

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, P.J.; Kelly, J.G.; Luera, T.F. [Sandia National Labs., Albuquerque, NM (United States); VanDenburg, J. [Science and Engineering Associates, Inc., Albuquerque, NM (United States)

    1993-11-01

    A compendium of dosimetry cross sections is presented for use in the characterization of fission reactor spectrum and fluence. The contents of this cross section library are based upon the ENDF/B-VI and IRDF-90 cross section libraries and are recommended as a replacement for the DOSCROS84 multigroup library that is widely used by the dosimetry community. Documentation is provided on the rationale for the choice of the cross sections selected for inclusion in this library and on the uncertainty and variation in cross sections presented by state-of-the-art evaluations.

  11. [Fast neutron cross section measurements

    International Nuclear Information System (INIS)

    Knoll, G.F.

    1992-01-01

    From its inception, the Nuclear Data Project at the University of Michigan has concentrated on two major objectives: (1) to carry out carefully controlled nuclear measurements of the highest possible reliability in support of the national nuclear data program, and (2) to provide an educational opportunity for students with interests in experimental nuclear science. The project has undergone a successful transition from a primary dependence on our photoneutron laboratory to one in which our current research is entirely based on a unique pulsed 14 MeV fast neutron facility. The new experimental facility is unique in its ability to provide nanosecond bursts of 14 MeV neutrons under conditions that are ''clean'' and as scatter-free as possible, and is the only one of its type currently in operation in the United States. It has been designed and put into operation primarily by graduate students, and has met or exceeded all of its important initial performance goals. We have reached the point of its routine operation, and most of the data are now in hand that will serve as the basis for the first two doctoral dissertations to be written by participating graduate students. Our initial results on double differential neutron cross sections will be presented at the May 1993 Fusion Reactor Technology Workshop. We are pleased to report that, after investing several years in equipment assembly and optimization, the project has now entered its ''data production'' phase

  12. Reaction cross section for Ne isotopes

    International Nuclear Information System (INIS)

    Panda, R.N.; Sahu, B.K.; Patra, S.K.

    2012-01-01

    In the present contribution, first the bulk properties are calculated, such as binding energy (BE), root mean square charge radius r ch , matter radius r m and quadrupole deformation parameter β 2 for 18-32 Ne isotopes in the Relativistic mean field (RMF) and effective field theory motivated RMF (E-RMF) formalisms . Then the total nuclear reaction cross section σR is analyzes for the scattering of 20 Ne and 28-32 Ne from a 12 C target at 240 MeV/nucleon by using the RMF model. Thus the objective of the present study is to calculate the bulk properties as well as a systematic analysis of σR over a range of neutron rich nuclei in the frame work of Glauber model

  13. The physical environment as a fall risk factor in older adults: Systematic review and meta-analysis of cross-sectional and cohort studies.

    Science.gov (United States)

    Letts, Lori; Moreland, Julie; Richardson, Julie; Coman, Liliana; Edwards, Mary; Ginis, Kathleen Martin; Wilkins, Seanne; Wishart, Laurie

    2010-02-01

    Evidence that the physical environment is a fall risk factor in older adults is inconsistent. The study evaluated and summarised evidence of the physical environment as a fall risk factor. Eight databases (1985-2006) were searched. Investigators evaluated quality of two categories (cross-sectional and cohort) of studies, extracted and analysed data. Cross-sectional: falls occur in a variety of environments; gait aids were present in approximately 30% of falls. Home hazards increased fall risk (odds ratio (OR) = 1.15; 95% confidence interval (CI): 0.97-1.36) although not significantly. When only the high quality studies were included, the OR = 1.38 (95% CI: 1.03-1.87), which was statistically significant. Use of mobility aids significantly increased fall risk in community (OR = 2.07; 95% CI: 1.59-2.71) and institutional (OR = 1.77; 95% CI: 1.66-1.89) settings. Home hazards appear to be a significant risk factor in older community-dwelling adults, although they may present the greatest risk for persons who fall repeatedly. Future research should examine relationships between mobility impairments, use of mobility aids and falls.

  14. Scattering cross section for various potential systems

    Energy Technology Data Exchange (ETDEWEB)

    Odsuren, Myagmarjav; Khuukhenkhuu, Gonchigdorj; Davaa, Suren [Nuclear Research Center, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar (Mongolia); Kato, Kiyoshi [Nuclear Reaction Data Centre, Faculty of Science, Hokkaido University, Sapporo (Japan)

    2017-08-15

    We discuss the problems of scattering in this framework, and show that the applied method is very useful in the investigation of the effect of the resonance in the observed scattering cross sections. In this study, not only the scattering cross sections but also the decomposition of the scattering cross sections was computed for the α–α system. To obtain the decomposition of scattering cross sections into resonance and residual continuum terms, the complex scaled orthogonality condition model and the extended completeness relation are used. Applying the present method to the α–α and α–n systems, we obtained good reproduction of the observed phase shifts and cross sections. The decomposition into resonance and continuum terms makes clear that resonance contributions are dominant but continuum terms and their interference are not negligible. To understand the behavior of observed phase shifts and the shape of the cross sections, both resonance and continuum terms are calculated.

  15. Scattering cross section for various potential systems

    Directory of Open Access Journals (Sweden)

    Myagmarjav Odsuren

    2017-08-01

    Full Text Available We discuss the problems of scattering in this framework, and show that the applied method is very useful in the investigation of the effect of the resonance in the observed scattering cross sections. In this study, not only the scattering cross sections but also the decomposition of the scattering cross sections was computed for the α–α system. To obtain the decomposition of scattering cross sections into resonance and residual continuum terms, the complex scaled orthogonality condition model and the extended completeness relation are used. Applying the present method to the α–α and α–n systems, we obtained good reproduction of the observed phase shifts and cross sections. The decomposition into resonance and continuum terms makes clear that resonance contributions are dominant but continuum terms and their interference are not negligible. To understand the behavior of observed phase shifts and the shape of the cross sections, both resonance and continuum terms are calculated.

  16. Photoelectric cross sections around the K edge

    International Nuclear Information System (INIS)

    Lingam, S.C.; Babu, K.S.; Reddy, D.V.K.

    1983-01-01

    Total attenuation cross sections for four elements, Ta, W, Au and Pb, were measured at the photon energies 32.1, 52, 72.1, 84.3, 145.4 and 279.2 keV. A good narrow beam geometry with two NaI (Tl) scintillation counters in conjunction with a single-channel analyser was used for the detection of low and medium energy photons. The measured total attenuation cross sections are compared with the theoretical compilations of Storm and Israel and the available earlier investigations. The scattering cross sections obtained by interpolation using the atomic data tables of Storm and Israel were subtracted from the measured total cross sections to obtain the photoelectric cross sections. The photoelectric cross sections thus derived are compared with the latest theoretical values of Scofield. (orig.)

  17. Background-cross-section-dependent subgroup parameters

    CERN Document Server

    Yamamoto, T

    2003-01-01

    A new set of subgroup parameters was derived that can reproduce the self-shielded cross section against a wide range of background cross sections. The subgroup parameters are expressed with a rational equation which numerator and denominator are expressed as the expansion series of background cross section, so that the background cross section dependence is exactly taken into account in the parameters. The advantage of the new subgroup parameters is that they can reproduce the self-shielded effect not only by group basis but also by subgroup basis. Then an adaptive method is also proposed which uses fitting procedure to evaluate the background-cross-section-dependence of the parameters. One of the simple fitting formula was able to reproduce the self-shielded subgroup cross section by less than 1% error from the precise evaluation. (author)

  18. Cross-section methodology in SIMMER

    International Nuclear Information System (INIS)

    Soran, P.D.

    1975-11-01

    The cross-section methodology incorporated in the SIMMER code is described. Data base for all cross sections is the ENDF/B system with various progressing computer codes to group collapse and modify the group constants which are used in SIMMER. Either infinitely dilute cross sections or the Bondarenko formalism can be used in SIMMER. Presently only a microscopic treatment is considered, but preliminary macroscopic algorithms have been investigated

  19. Measurements of neutron capture cross sections

    International Nuclear Information System (INIS)

    Nakajima, Yutaka

    1984-01-01

    A review of measurement techniques for the neutron capture cross sections is presented. Sell transmission method, activation method, and prompt gamma-ray detection method are described using examples of capture cross section measurements. The capture cross section of 238 U measured by three different prompt gamma-ray detection methods (large liquid scintillator, Moxon-Rae detector, and pulse height weighting method) are compared and their discrepancies are resolved. A method how to derive the covariance is described. (author)

  20. Cross Sections for Electron Collisions with Methane

    Energy Technology Data Exchange (ETDEWEB)

    Song, Mi-Young, E-mail: mysong@nfri.re.kr; Yoon, Jung-Sik [Plasma Technology Research Center, National Fusion Research Institute, 814-2 Osikdo-dong, Gunsan, Jeollabuk-do 573-540 (Korea, Republic of); Cho, Hyuck [Department of Physics, Chungnam National University, Daejeon 305-764 (Korea, Republic of); Itikawa, Yukikazu [Institute of Space and Astronautical Science, Sagamihara 252-5210 (Japan); Karwasz, Grzegorz P. [Faculty of Physics, Astronomy and Applied Informatics, University Nicolaus Copernicus, Grudziadzka 5, 87100 Toruń (Poland); Kokoouline, Viatcheslav [Department of Physics, University of Central Florida, Orlando, Florida 32816 (United States); Nakamura, Yoshiharu [6-1-5-201 Miyazaki, Miyamae, Kawasaki 216-0033 (Japan); Tennyson, Jonathan [Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT (United Kingdom)

    2015-06-15

    Cross section data are compiled from the literature for electron collisions with methane (CH{sub 4}) molecules. Cross sections are collected and reviewed for total scattering, elastic scattering, momentum transfer, excitations of rotational and vibrational states, dissociation, ionization, and dissociative attachment. The data derived from swarm experiments are also considered. For each of these processes, the recommended values of the cross sections are presented. The literature has been surveyed through early 2014.

  1. pp Partial cross sections at low energy

    International Nuclear Information System (INIS)

    Benedettini, A.; Bertin, A.; Bruschi, M.; Capponi, M.; Collamati, A.; D'Antone, I.; De Castro, S.; Dona, R.; Ferretti, A.; Galli, D.; Giacobbe, B.; Marconi, U.; Massa, I.; Piccinini, M.

    1997-01-01

    New measurements of the pp total annihilation cross-section at very low momenta (around 50 MeV/c) confirm the previous results obtained by the OBELIX collaboration. The measured values are in general agreement with the scattering length approximation of the annihilation cross-section, where the pp scattering lengths are obtained from measurement of the protonium shifts and widths and which accounts for the Coulomb interaction. Partial annihilation cross-sections and annihilation frequencies for some channels have been measured too. The values of the total and partial cross sections at the lowest p momentum show an unexpected behaviour. (orig.)

  2. Curves and tables of neutron cross sections

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo; Asami, Tetsuo; Yoshida, Tadashi

    1990-07-01

    Neutron cross-section curves from the Japanese Evaluated Nuclear Data Library version 3, JENDL-3, are presented in both graphical and tabular form for users in a wide range of application areas in the nuclear energy field. The contents cover cross sections for all the main reactions induced by neutrons with an energy below 20 MeV including; total, elastic scattering, capture, and fission, (n,n'), (n,2n), (n,3n), (n,α), (n,p) reactions. The 2200 m/s cross-section values, resonance integrals, and Maxwellian- and fission-spectrum averaged cross sections are also tabulated. (author)

  3. Damage cross-section library DAMSIG81

    International Nuclear Information System (INIS)

    Zijp, W.L.; Nolthenius, H.J.; Rieffe, H.Ch.

    1981-11-01

    The damage cross-section library DAMSIG81 is an updated and extended version of the damage cross-section library (DAMSIG77). The library contains energy dependent group cross section data for a number of materials to facilitate the calculations of damage production (based on displacements of atoms), the calculation of probable zones and the calculation of gas production due to (n,α) and (n,p) reactions. The group cross-section data are given for a fine group structure of the SAND-II type with 640 groups. This library contains for some materials more than one cross-section set originating from different evaluations. Cross section data sets for the activation reactions 54 Fe(n,p), 58 Ni(n,p), and 63 Cu(n,α), which reactions are commonly used to determine thermal and fast neutron fluences, have been included also. Moreover also some artificial cross-sections are incorporated in this library which can be used to calculate values for some physical quantities characterizing neutron spectra, such as mean lethargy , mean energy . Also cross-sections for B, Al, and Cd are included; these are required to reach compatibility with other libraries in the SAND-II format

  4. Total cross section of highly excited strings

    International Nuclear Information System (INIS)

    Lizzi, F.; Senda, I.

    1990-01-01

    The unpolarized total cross section for the joining of two highly excited strings is calculated. The calculation is performed by taking the average overall states in the given excitation levels of the initial strings. We find that the total cross section grows with the energy and momentum of the initial states. (author). 8 refs, 1 fig

  5. Compilation of cross-sections. Pt. 4

    International Nuclear Information System (INIS)

    Alekhin, S.I.; Ezhela, V.V.; Lugovsky, S.B.; Tolstenkov, A.N.; Yushchenko, O.P.; Baldini, A.; Cobal, M.; Flaminio, V.; Capiluppi, P.; Giacomelli, G.; Mandrioli, G.; Rossi, A.M.; Serra, P.; Moorhead, W.G.; Morrison, D.R.O.; Rivoire, N.

    1987-01-01

    This is the fourth volume in our series of data compilations on integrated cross-sections for weak, electromagnetic, and strong interaction processes. This volume covers data on reactions induced by photons, neutrinos, hyperons, and K L 0 . It contains all data published up to June 1986. Plots of the cross-sections versus incident laboratory momentum are also given. (orig.)

  6. Compilation of cross-sections. Pt. 1

    International Nuclear Information System (INIS)

    Flaminio, V.; Moorhead, W.G.; Morrison, D.R.O.; Rivoire, N.

    1983-01-01

    A compilation of integral cross-sections for hadronic reactions is presented. This is an updated version of CERN/HERA 79-1, 79-2, 79-3. It contains all data published up to the beginning of 1982, but some more recent data have also been included. Plots of the cross-sections versus incident laboratory momentum are also given. (orig.)

  7. Total cross section results for deuterium electrodisintegration

    International Nuclear Information System (INIS)

    Skopik, D.M.; Murphy, J.J. II; Shin, Y.M.

    1976-01-01

    Theoretical total cross sections for deuterium electrodisintegration are presented as a function of incident electron energy. The cross section has been calculated using virtual photon theory with Partovi's photodisintegration calculation for E/subx/ > 10 MeV and effective range theory for E/subx/ 2 H(e, n) reaction in Tokamak reactors

  8. Recommended evaluation procedure for photonuclear cross section

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young-Ouk; Chang, Jonghwa; Fukahori, Tokio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-03-01

    In order to generate photonuclear cross section library for the necessary applications, data evaluation is combined with theoretical evaluation, since photonuclear cross sections measured cannot provide all necessary data. This report recommends a procedure consisting of four steps: (1) analysis of experimental data, (2) data evaluation, (3) theoretical evaluation and, if necessary, (4) modification of results. In the stage of analysis, data obtained by different measurements are reprocessed through the analysis of their discrepancies to a representative data set. In the data evaluation, photonuclear absorption cross sections are evaluated via giant dipole resonance and quasi-deutron mechanism. With photoabsorption cross sections from the data evaluation, theoretical evaluation is applied to determine various decay channel cross sections and emission spectra using equilibrium and preequilibrium mechanism. After this, the calculated results are compared with measured data, and in some cases the results are modified to better describe measurements. (author)

  9. Technology-assisted risk of bias assessment in systematic reviews: a prospective cross-sectional evaluation of the RobotReviewer machine learning tool.

    Science.gov (United States)

    Gates, Allison; Vandermeer, Ben; Hartling, Lisa

    2018-04-01

    To evaluate the reliability of RobotReviewer's risk of bias judgments. In this prospective cross-sectional evaluation, we used RobotReviewer to assess risk of bias among 1,180 trials. We computed reliability with human reviewers using Cohen's kappa coefficient and calculated sensitivity and specificity. We investigated differences in reliability by risk of bias domain, topic, and outcome type using the chi-square test in meta-analysis. Reliability (95% CI) was moderate for random sequence generation (0.48 [0.43, 0.53]), allocation concealment (0.45 [0.40, 0.51]), and blinding of participants and personnel (0.42 [0.36, 0.47]); fair for overall risk of bias (0.34 [0.25, 0.44]); and slight for blinding of outcome assessors (0.10 [0.06, 0.14]), incomplete outcome data (0.14 [0.08, 0.19]), and selective reporting (0.02 [-0.02, 0.05]). Reliability for blinding of participants and personnel (P risk of bias (P Risk of bias appraisal is subjective. Compared with reliability between author groups, RobotReviewer's reliability with human reviewers was similar for most domains and better for allocation concealment, blinding of participants and personnel, and overall risk of bias. Copyright © 2018 Elsevier Inc. All rights reserved.

  10. Developing cross section sets for fluorocarbon etchants

    International Nuclear Information System (INIS)

    Winstead, Carl; McKoy, Vincent

    2002-01-01

    Successful modeling of plasmas used in materials processing depends on knowledge of a variety of collision cross sections and reaction rates, both within the plasma and at the surface. Electron-molecule collision cross sections are especially important, affecting both electron transport and the generation of reactive fragments by dissociation and ionization. Because the supply of cross section data is small and measurements are difficult, computational approaches may make a valuable contribution, provided they can cope with the significant challenges posed. In particular, a computational method must deal with the full complexity of low-energy electron-molecule interactions, must treat polyatomic molecules, and must be capable of computing cross sections for electronic excitation. These requirements imply that the method will be numerically intensive and thus must exploit high-performance computers to be practical. We have developed an ab initio computational method, the Schwinger multichannel (SMC) method, that possesses the characteristics just described, and we have applied it to compute cross sections for a variety of molecules, with particular emphasis on fluorocarbon and hydrofluorocarbon etchants used in the semiconductor industry. A key aspect of this work has been an awareness that cross section sets, validated when possible against swarm data, are more useful than individual cross sections. To develop such sets, cross section calculations must be integrated within a focused collaborative effort. Here we describe electron cross section calculations carried out within the context of such a focused effort, with emphasis on fluorinated hydrocarbons including CHF3 (trifluoromethane), c-C4F8 (octafluorocyclobutane), and C2F4 (tetrafluoroethene)

  11. Differential Top Cross-section Measurements

    CERN Document Server

    Fenton, Michael James; The ATLAS collaboration

    2017-01-01

    The top quark is the heaviest known fundamental particle. The measurement of the differential top-quark pair production cross-section provides a stringent test of advanced perturbative QCD calculations. The ATLAS collaboration has performed detailed measurements of those differential cross sections at a centre-of-mass energy of 13 TeV. This talk focuses on differential cross-section measurements in the lepton+jets final state, including using boosted top quarks to probe our understanding of top quark production in the TeV regime.

  12. NNLO jet cross sections by subtraction

    International Nuclear Information System (INIS)

    Somogyi, G.; Bolzoni, P.; Trocsanyi, Z.

    2010-06-01

    We report on the computation of a class of integrals that appear when integrating the so-called iterated singly-unresolved approximate cross section of an earlier NNLO subtraction scheme over the factorised phase space of unresolved partons. The integrated approximate cross section itself can be written as the product of an insertion operator (in colour space) times the Born cross section. We give selected results for the insertion operator for processes with two and three hard partons in the final state. (orig.)

  13. Compilation of cross-sections. Pt. 3

    International Nuclear Information System (INIS)

    Flaminio, V.; Moorhead, W.G.; Morrison, D.R.O.; Rivoire, N.

    1984-01-01

    A compilation of integrated cross-sections for hadronic reactions is presented. This is an updated version of CERN/HERA 79-1, 79-2, 79-3. It contains all data published up to the beginning of 1982, but some more recent data, particularly those from the CERN Collider, have also been included. Plots of the cross-sections versus incident laboratory momentum are also given. This volume III contains cross-sections for p and anti p induced reactions. (orig.)

  14. Pion-nucleus cross sections approximation

    International Nuclear Information System (INIS)

    Barashenkov, V.S.; Polanski, A.; Sosnin, A.N.

    1990-01-01

    Analytical approximation of pion-nucleus elastic and inelastic interaction cross-section is suggested, with could be applied in the energy range exceeding several dozens of MeV for nuclei heavier than beryllium. 3 refs.; 4 tabs

  15. Status of neutron dosimetry cross sections

    International Nuclear Information System (INIS)

    Griffin, P.J.; Kelly, J.G.

    1992-01-01

    Several new cross section libraries, such as ENDF/B-VI(release 2), IRDF-90,JEF-2.2, and JENDL-3 Dosimetry, have recently been made available to the dosimetry community. the Sandia National Laboratories (SNL) Radiation Metrology Laboratory (RML) has worked with these libraries since pre-release versions were available. this paper summarizes the results of the intercomparison and testing of dosimetry cross sections. As a result of this analysis, a compendium of the best dosimetry cross sections was assembled from the available libraries for use within the SNL RML. this library, referred to as the SNLRML Library, contains 66 general dosimetry sensors and 3 special dosimeters unique to the RML sensor inventory. The SNLRML cross sections have been put into a format compatible with commonly used spectrum determination codes

  16. Fission cross section measurements at intermediate energies

    International Nuclear Information System (INIS)

    Laptev, Alexander

    2005-01-01

    The activity in intermediate energy particle induced fission cross-section measurements of Pu, U isotopes, minor actinides and sub-actinides in PNPI of Russia is reviewed. The neutron-induced fission cross-section measurements are under way in the wide energy range of incident neutrons from 0.5 MeV to 200 MeV at the GNEIS facility. In number of experiments at the GNEIS facility, the neutron-induced fission cross sections were obtained for many nuclei. In another group of experiments the proton-induced fission cross-section have been measured for proton energies ranging from 200 to 1000 MeV at 100 MeV intervals using the proton beam of PNPI synchrocyclotron. (author)

  17. Measurement of multinucleon transfer cross-sections

    Indian Academy of Sciences (India)

    Keywords. Ni(C, ), Fe(C, ), =C, C, B, B, Be, Be, Be, Be, Li, Li; = 60 MeV; measured reaction cross-section; elastic scattering angular distribution; deduced transfer probabilities and enhancement factors.

  18. The hadronic cross section measurement at KLOE

    International Nuclear Information System (INIS)

    Aloisio, A.; Ambrosino, F.; Antonelli, A.; Antonelli, M.; Bacci, C.; Barva, M.; Bencivenni, G.; Bertolucci, S.; Bini, C.; Bloise, C.; Bocci, V.; Bossi, F.; Branchini, P.; Bulychjov, S.A.; Caloi, R.; Campana, P.; Capon, G.; Capussela, T.; Carboni, G.; Ceradini, F.; Cervelli, F.; Cevenini, F.; Chiefari, G.; Ciambrone, P.; Conetti, S.; De Lucia, E.; De Santis, A.; De Simone, P.; De Zorzi, G.; Dell'Agnello, S.; Denig, A.; Di Domenico, A.; Di Donato, C.; Di Falco, S.; Di Micco, B.; Doria, A.; Dreucci, M.; Erriquez, O.; Farilla, A.; Felici, G.; Ferrari, A.; Ferrer, M.L.; Finocchiaro, G.; Forti, C.; Franzini, P.; Gatti, C.; Gauzzi, P.; Giovannella, S.; Gorini, E.; Graziani, E.; Incagli, M.; Kluge, W.; Kulikov, V.; Lacava, F.; Lanfranchi, G.; Lee-Franzini, J.; Leone, D.; Lu, F.; Martemianov, M.; Martini, M.; Matsyuk, M.; Mei, W.; Merola, L.; Messi, R.; Miscetti, S.; Moulson, M.; Mueller, S.; Murtas, F.; Napolitano, M.; Nguyen, F.; Palutan, M.; Pasqualucci, E.; Passalacqua, L.; Passeri, A.; Patera, V.; Perfetto, F.; Petrolo, E.; Pontecorvo, L.; Primavera, M.; Santangelo, P.; Santovetti, E.; Saracino, G.; Schamberger, R.D.; Sciascia, B.; Sciubba, A.; Scuri, F.; Sfiligoi, I.; Sibidanov, A.; Spadaro, T.; Spiriti, E.; Tabidze, M.; Testa, M.; Tortora, L.; Valente, P.; Valeriani, B.; Venanzoni, G.; Veneziano, S.; Ventura, A.; Versaci, R.; Villella, I.; Xu, G.

    2005-01-01

    KLOE uses the radiative return to measure cross section σ(e + e - ->π + π - γ) at the electron-positron collider DAΦNE. Divinding by a theoretical radiator function, we obtain the cross section σ(e + e - ->π + π - γ) for the mass range 0.35 π 2 . We calculate the hadronic contribution to the muon anomaly for the given mass range: a μ =388.7+/-0.8 stat +/-3.5syst+/-3.5 th

  19. Actinide cross section program at ORELA

    International Nuclear Information System (INIS)

    Dabbs, J.W.T.

    1980-01-01

    The actinide cross section program at ORELA, the Oak Ridge Electron Linear Accelerator, is aimed at obtaining accurate neutron cross sections (primarily fission, capture, and total) for actinide nuclides which occur in fission reactors. Such cross sections, measured as a function of neutron energy over as wide a range of energies as feasible, comprise a data base that permits calculated predictions of the formation and removal of these nuclides in reactors. The present program is funded by the Division of Basic Energy Sciences of DOE, and has components in several divisions at ORNL. For intensively α-active nuclides, many of the existing fission cross section data have been provided by underground explosions. New measurement techniques, developed at ORELA, now permit linac measurements on fissionable nuclides with alpha half-lives as short as 28 years. Capture and capture-plus-fission measurements utilize scintillation detectors (of capture γ rays and fission neutrons) in which pulse shape discrimination plays an important role. Total cross sections can be measured at ORELA on samples of only a few milligrams. A simultaneous program of chemical and isotopic analyses of samples irradiated in EBR-II is in progress to provide benchmarks for the existing differential measurements. These analyses are being studied with updated versions of ORIGEN and with sensitivity determinations. Calculations of the sensitivity to cross section changes of various aspects of the nuclear fuel cycle are also being made. Even in this relatively mature field, many cross sections still require improvements to provide an adequate data base. Examples of recent techniques and measurements are presented. 12 figures, 3 tables

  20. Neutron cross sections for 3He at epithermal energies

    International Nuclear Information System (INIS)

    Keith, C.D.; Chowdhuri, Z.; Rich, D.R.; Snow, W.M.; Bowman, J.D.; Penttilae, S.L.; Smith, D.A.; Leuschner, M.B.; Pomeroy, V.R.; Jones, G.L.; Sharapov, E.I.

    2004-01-01

    High accuracy, absolute measurements of the neutron total cross section for 3 He are reported for incident neutron energies 0.1-400 eV. The measurements were performed at the LANSCE short-pulse neutron spallation source. Using the previously determined cross section for neutron elastic scattering, 3.367±0.019 b, we extract a new value for the energy dependence of the 3 He(n,p) 3 He reaction cross section, σ np =(849.77±0.14±1.02)E -1/2 -(1.253±0.00± -0.049 +0.008 )b, where the neutron energy is expressed in eV. The first uncertainty is statistical, the second systematic.

  1. Top quark production cross-section measurements

    CERN Document Server

    Chen, Ye; The ATLAS collaboration

    2017-01-01

    Measurements of the inclusive and differential cross-sections for top-quark pair and single top production cross sections in proton-proton collisions with the ATLAS detector at the Large Hadron Collider are presented at center-of-mass energies of 8 TeV and 13 TeV. The inclusive measurements reach high precision and are compared to the best available theoretical calculations. These measurements, including results using boosted tops, probe our understanding of top-pair production in the TeV regime. The results are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers and NLO QCD calculations. For the t-channel single top measurement, the single top-quark and anti-top-quark total production cross-sections, their ratio, as well as differential cross sections are also presented. A measurement of the production cross-section of a single top quark in association with a W boson, the second largest single-top production mode, is also presented. Finally, measurements of ...

  2. Neutrino–nucleus cross sections for oscillation experiments

    Science.gov (United States)

    Katori, Teppei; Martini, Marco

    2018-01-01

    Neutrino oscillations physics is entering an era of high precision. In this context, accelerator-based neutrino experiments need a reduction in systematic errors to the level of a few percent. Today, one of the most important sources of systematic errors are neutrino–nucleus cross sections which, in the energy region of hundreds of MeV to a few GeV, are known to a precision not exceeding 20%. In this article we review the present experimental and theoretical knowledge of neutrino–nucleus interaction physics. After introducing neutrino-oscillation physics and accelerator-based neutrino experiments, we give an overview of general aspects of neutrino–nucleus cross sections, from both the theoretical and experimental point of view. Then, we focus on these cross sections in different reaction channels. We start with the quasi-elastic and quasi-elastic-like cross section, placing a special emphasis on the multinucleon emission channel, which has attracted a lot of attention in the last few years. We review the main aspects of the different microscopic models for this channel by discussing analogies and the differences among them. The discussion is always driven by a comparison with the experimental data. We then consider the one-pion production channel where agreement between data and theory remains highly unsatisfactory. We describe how to interpret pion data, and then analyze, in particular, the puzzle related to the difficulty of theoretical models and Monte Carlo to simultaneously describe MiniBooNE and MINERvA experimental results. Inclusive cross sections are also discussed, as well as the comparison between the {ν }μ and {ν }e cross sections, relevant for the charge-conjugation-parity violation experiments. The impact of nuclear effects on the reconstruction of neutrino energy and on the determination of the neutrino-oscillation parameters is also reviewed. Finally, we look to the future by discussing projects and efforts in relation to future detectors

  3. Improving activation cross section data with TALYS

    Science.gov (United States)

    Dzysiuk, Nataliia; Koning, Arjan

    2017-09-01

    Needs for accurate (n,x) activation cross sections for fusion technology have been considered with reference to the current status of the TENDL library. The current work is focused on improving activation cross section data for nuclear reactions relevant mainly for fusion and astrophysical needs. The fits have been performed with the TALYS-1.8 code by means of nuclear model parameter variation, mostly for the optical model and level densities, followed by comparison to recent experimental data taken from EXFOR and other evaluated nuclear databases. The updated cross section data are going to be adopted into the new version of TENDL. The improvements have been performed both for differential as well as integral data sets.

  4. Prospects for Precision Neutrino Cross Section Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Harris, Deborah A. [Fermilab

    2016-01-28

    The need for precision cross section measurements is more urgent now than ever before, given the central role neutrino oscillation measurements play in the field of particle physics. The definition of precision is something worth considering, however. In order to build the best model for an oscillation experiment, cross section measurements should span a broad range of energies, neutrino interaction channels, and target nuclei. Precision might better be defined not in the final uncertainty associated with any one measurement but rather with the breadth of measurements that are available to constrain models. Current experience shows that models are better constrained by 10 measurements across different processes and energies with 10% uncertainties than by one measurement of one process on one nucleus with a 1% uncertainty. This article describes the current status of and future prospects for the field of precision cross section measurements considering the metric of how many processes, energies, and nuclei have been studied.

  5. Top Quark Production Cross Section Measurements

    CERN Document Server

    Massa, Lorenzo; The ATLAS collaboration

    2017-01-01

    Measurements of the inclusive and differential cross-sections for top-quark pair and single top production cross sectionsinproton-proton collisions with the ATLAS detector at the Large Hadron Collider are presented at centre of mass energies of 8 TeV and 13 TeV. The inclusive measurements reach high precision and are compared to the best available theoretical calculations. These measurements, including results using boosted tops, probe our understanding of top-pair production in the TeV regime. The results are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers and NLO QCD calculations. For the t-channel single top measurement, the single top-quark and anti-top-quark total production cross-sections, their ratio, as well as differential cross sections are also presented. A measurement of the production cross section of a single top quark in association witha W boson, the second largest single-top production mode, is also presented. Finally, measurements of t...

  6. Optical Model and Cross Section Uncertainties

    Energy Technology Data Exchange (ETDEWEB)

    Herman,M.W.; Pigni, M.T.; Dietrich, F.S.; Oblozinsky, P.

    2009-10-05

    Distinct minima and maxima in the neutron total cross section uncertainties were observed in model calculations using spherical optical potential. We found this oscillating structure to be a general feature of quantum mechanical wave scattering. Specifically, we analyzed neutron interaction with 56Fe from 1 keV up to 65 MeV, and investigated physical origin of the minima.We discuss their potential importance for practical applications as well as the implications for the uncertainties in total and absorption cross sections.

  7. The hadronic cross section measurement at KLOE

    Energy Technology Data Exchange (ETDEWEB)

    Aloisio, A.; Ambrosino, F.; Antonelli, A.; Antonelli, M.; Bacci, C.; Barva, M.; Bencivenni, G.; Bertolucci, S.; Bini, C.; Bloise, C.; Bocci, V.; Bossi, F.; Branchini, P.; Bulychjov, S.A.; Caloi, R.; Campana, P.; Capon, G.; Capussela, T.; Carboni, G.; Ceradini, F.; Cervelli, F.; Cevenini, F.; Chiefari, G.; Ciambrone, P.; Conetti, S.; De Lucia, E.; De Santis, A.; De Simone, P.; De Zorzi, G.; Dell' Agnello, S.; Denig, A.; Di Domenico, A.; Di Donato, C.; Di Falco, S.; Di Micco, B.; Doria, A.; Dreucci, M.; Erriquez, O.; Farilla, A.; Felici, G.; Ferrari, A.; Ferrer, M.L.; Finocchiaro, G.; Forti, C.; Franzini, P.; Gatti, C.; Gauzzi, P.; Giovannella, S.; Gorini, E.; Graziani, E.; Incagli, M.; Kluge, W.; Kulikov, V.; Lacava, F.; Lanfranchi, G.; Lee-Franzini, J.; Leone, D. [Institut fuer Experimentelle Kernphysik, Universitaet Karlsruhe Postfach 3640, D-76021 Karlsruhe (Germany); Lu, F.; Martemianov, M.; Martini, M.; Matsyuk, M.; Mei, W.; Merola, L.; Messi, R.; Miscetti, S.; Moulson, M.; Mueller, S.; Murtas, F.; Napolitano, M.; Nguyen, F.; Palutan, M.; Pasqualucci, E.; Passalacqua, L.; Passeri, A.; Patera, V.; Perfetto, F.; Petrolo, E.; Pontecorvo, L.; Primavera, M.; Santangelo, P.; Santovetti, E.; Saracino, G.; Schamberger, R.D.; Sciascia, B.; Sciubba, A.; Scuri, F.; Sfiligoi, I.; Sibidanov, A.; Spadaro, T.; Spiriti, E.; Tabidze, M.; Testa, M.; Tortora, L.; Valente, P.; Valeriani, B.; Venanzoni, G.; Veneziano, S.; Ventura, A.; Versaci, R.; Villella, I.; Xu, G

    2005-07-15

    KLOE uses the radiative return to measure cross section {sigma}(e{sup +}e{sup -}->{pi}{sup +}{pi}{sup -}{gamma}) at the electron-positron collider DA{phi}NE. Divinding by a theoretical radiator function, we obtain the cross section {sigma}(e{sup +}e{sup -}->{pi}{sup +}{pi}{sup -}{gamma}) for the mass range 0.35

  8. Covariance Evaluation Methodology for Neutron Cross Sections

    Energy Technology Data Exchange (ETDEWEB)

    Herman,M.; Arcilla, R.; Mattoon, C.M.; Mughabghab, S.F.; Oblozinsky, P.; Pigni, M.; Pritychenko, b.; Songzoni, A.A.

    2008-09-01

    We present the NNDC-BNL methodology for estimating neutron cross section covariances in thermal, resolved resonance, unresolved resonance and fast neutron regions. The three key elements of the methodology are Atlas of Neutron Resonances, nuclear reaction code EMPIRE, and the Bayesian code implementing Kalman filter concept. The covariance data processing, visualization and distribution capabilities are integral components of the NNDC methodology. We illustrate its application on examples including relatively detailed evaluation of covariances for two individual nuclei and massive production of simple covariance estimates for 307 materials. Certain peculiarities regarding evaluation of covariances for resolved resonances and the consistency between resonance parameter uncertainties and thermal cross section uncertainties are also discussed.

  9. Neutron Capture Cross Section of 239Pu

    Science.gov (United States)

    Mosby, S.; Arnold, C.; Bredeweg, T. A.; Couture, A.; Jandel, M.; O'Donnell, J. M.; Rusev, G.; Ullmann, J. L.; Chyzh, A.; Henderson, R.; Kwan, E.; Wu, C. Y.

    2014-09-01

    The 239Pu(n,γ) cross section has been measured over the energy range 10 eV - 10 keV using the Detector for Advanced Neutron Capture Experiments (DANCE) as part of a campaign to produce precision (n,γ) measurements on 239Pu in the keV region. Fission coincidences were measured with a PPAC and used to characterize the prompt fission γ-ray spectrum in this region. The resulting spectra will be used to better characterize the fission component of another experiment with a thicker target to extend the (n,γ) cross section measurement well into the keV region.

  10. Updated ozone absorption cross section will reduce air quality compliance

    Directory of Open Access Journals (Sweden)

    E. D. Sofen

    2015-12-01

    et al. (2015 as 1.8 % smaller than the accepted value (Hearn, 1961 used for the preceding 50 years. Thus, ozone measurements that applied the older cross section systematically underestimate the amount of ozone in air. We correct the reported historical surface data from North America and Europe and find that this modest change in cross section has a significant impact on the number of locations that are out of compliance with air quality regulations if the air quality standards remain the same. We find 18, 23, and 20 % increases in the number of sites that are out of compliance with current US, Canadian, and European ozone air quality health standards for the year 2012. Should the new cross-section value be applied, it would impact attainment of air quality standards and compliance with relevant clean air acts, unless the air quality target values themselves were also changed proportionately. We draw attention to how a small change in gas metrology has a global impact on attainment and compliance with legal air quality standards. We suggest that further laboratory work to evaluate the new cross section is needed and suggest three possible technical and policy responses should the new cross section be adopted.

  11. Cross Sections From Scalar Field Theory

    Science.gov (United States)

    Norbury, John W.; Dick, Frank; Norman, Ryan B.; Nasto, Rachel

    2008-01-01

    A one pion exchange scalar model is used to calculate differential and total cross sections for pion production through nucleon- nucleon collisions. The collisions involve intermediate delta particle production and decay to nucleons and a pion. The model provides the basic theoretical framework for scalar field theory and can be applied to particle production processes where the effects of spin can be neglected.

  12. Single top quark cross sections at ATLAS

    CERN Document Server

    Finelli, Kevin Daniel; The ATLAS collaboration

    2018-01-01

    This presentation covers single top production in the t-channel, s-channel, tW, and tZq production modes. Differential cross-sections for t-channel and tW are covered, as well as the latest inclusive measurements in s-channel and tZq.

  13. Validation of evaluated neutron standard cross sections

    International Nuclear Information System (INIS)

    Badikov, S.; Golashvili, T.

    2008-01-01

    Some steps of the validation and verification of the new version of the evaluated neutron standard cross sections were carried out. In particular: -) the evaluated covariance data was checked for physical consistency, -) energy-dependent evaluated cross-sections were tested in most important neutron benchmark field - 252 Cf spontaneous fission neutron field, -) a procedure of folding differential standard neutron data in group representation for preparation of specialized libraries of the neutron standards was verified. The results of the validation and verification of the neutron standards can be summarized as follows: a) the covariance data of the evaluated neutron standards is physically consistent since all the covariance matrices of the evaluated cross sections are positive definite, b) the 252 Cf spectrum averaged standard cross-sections are in agreement with the evaluated integral data (except for 197 Au(n,γ) reaction), c) a procedure of folding differential standard neutron data in group representation was tested, as a result a specialized library of neutron standards in the ABBN 28-group structure was prepared for use in reactor applications. (authors)

  14. Elastic and inelastic neutron cross-sections

    International Nuclear Information System (INIS)

    Wilmore, D.

    1967-01-01

    Computer programmes have been developed for the calculation of elastic and inelastic scattering of particles from nuclei. These programmes are written in the S2 dialect of FORTRAN, and run on an IBM-7030 computer. One programme calculates the shape elastic cross-section, the total cross-section and the absorption cross-section according to the optical model. The time taken in performing an optical calculation depends mainly upon the efficiency of the method used to perform the integration of the radial Schroedinger equation. A method is used which takes advantage of the absence of the first derivative term, and this gives a great improvement over more general methods. A least-squares fitting procedure is used which enables any number of parameters to be varied. The number of optical model calculations which are needed for a least-squares fit is less than with usual methods. Another programme will calculate compound nucleus reactions according to the Hauser-Feshbach theory, with or without the fluctuation correction. This programme will accept target and projectiles of any spin and parity, so that deuteron and alpha channels, as well as nucleon channels, may be taken into account. A third programme enables least-squares fits of elastic scattering to be done by taking into account the compound elastic contribution as calculated by the Hauser-Feshbach theory. The use of these programmes is illustrated by the analysis of the inelastic scattering of neutrons from 238 U. The elastic scattering cross-sections were used to obtain optical potentials by a least-squares fitting method. These potentials were subsequently used to predict the inelastic cross-sections to a large number of excited states. The results using the fluctuation correction are in good agreement with experiment. A further example of their use is shown in the analysis of neutron and proton scattering from light nuclei. Proton cross-sections were analysed to obtain potentials which were then used to

  15. Absolute np and pp cross section determinations aimed at improving the standard for cross section measurements

    International Nuclear Information System (INIS)

    Laptev, Alexander B.; Haight, Robert C.; Tovesson, Fredrik; Arndt, Richard A.; Briscoe, William J.; Paris, Mark W.; Strakovsky, Igor I.; Workman, Ron L.

    2010-01-01

    Purpose of present research is a keeping improvement of the standard for cross section measurements of neutron-induced reactions. The cross sections for np and pp scattering below 1000 MeV are determined based on partial-wave analyses (PW As) of nucleon-nucleon scattering data. These cross sections are compared with the most recent ENDF/B-V11.0 and JENDL-4.0 data files, and the Nijmegen PWA. Also a comparison of evaluated data with recent experimental data was made to check a quality of evaluation. Excellent agreement was found between the new experimental data and our PWA predictions.

  16. Electron-collision cross sections for iodine

    International Nuclear Information System (INIS)

    Zatsarinny, O.; Bartschat, K.; Garcia, G.; Blanco, F.; Hargreaves, L.R.; Jones, D.B.; Murrie, R.; Brunton, J.R.; Brunger, M.J.; Hoshino, M.; Buckman, S.J.

    2011-01-01

    We present results from a joint experimental and theoretical study of elastic electron scattering from atomic iodine. The experimental results were obtained by subtracting known cross sections from the measured data obtained with a pyrolyzed mixed beam containing a variety of atomic and molecular species. The calculations were performed using both a fully relativistic Dirac B-spline R-matrix (close-coupling) method and an optical model potential approach. Given the difficulty of the problem, the agreement between the two sets of theoretical predictions and the experimental data for the angle-differential and the angle-integrated elastic cross sections at 40 eV and 50 eV is satisfactory.

  17. Cross sections required for FMIT dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Gold, R.; McElroy, W.N.; Lippincott, E.P.; Mann, F.M.; Oberg, D.L.; Roberts, J.H.; Ruddy, F.H.

    1980-05-02

    The Fusion Materials Irradiation Test (FMIT) facility, currently under construction, is designed to produce a high flux of high energy neutrons for irradiation effects experiments on fusion reactor materials. Characterization of the flux-fluence-spectrum in this rapidly varying neutron field requires adaptation and extension of currently available dosimetry techniques. This characterization will be carried out by a combination of active, passive, and calculational dosimetry. The goal is to provide the experimenter with accurate neutron flux-fluence-spectra at all positions in the test cell. Plans have been completed for a number of experimental dosimetry stations and provision for these facilities has been incorporated into the FMIT design. Overall needs of the FMIT irradiation damage program delineate goal accuracies for dosimetry that, in turn, create new requirements for high energy neutron cross section data. Recommendations based on these needs have been derived for required cross section data and accuracies.

  18. Test of RIPL-2 cross section calculations

    International Nuclear Information System (INIS)

    Herman, M.

    2002-01-01

    The new levels and optical segments and microscopic HF-BCS level densities (part of the density segment) were tested in practical calculations of cross sections for neutron induced reactions on 22 targets (40-Ca, 47-Ti, 52-Cr, 55-Mn, 58-Ni, 63-Cu, 71-Ga, 80-Se, 92-Mo, 93-Nb, 100-Mo, 109-Ag, 114-Cd, 124-Sn, 127-I, 133-Cs, 140-Ce, 153-Eu, 169-Tm, 186-W, 197-Au, 208-Pb). For each target all reactions involving up to 3 neutron, 1 proton and 1 α-particle emissions (subject to actual reaction thresholds) were considered in the incident energy range from 1 keV up to 20 MeV (in some cases up to 27 MeV). In addition, total, elastic, and neutron capture cross sections were calculated

  19. Neutron cross section measurements at WNR

    International Nuclear Information System (INIS)

    Lisowski, P.W.; Archampaugh, G.F.; Moore, M.S.; Morgan, G.L.; Shamu, R.E.

    1980-01-01

    The Weapons Neutron Research Facility has been used to obtain moderate-resolution total neutron cross section data for H, C, 208 Pb, 232 Th, 238 U, and 242 Pu over the energy range 5 to 200 MeV. Neutrons were produced by bombarding a 2.5-cm diam by 15-cm long Ta target with an 800 MeV pulsed proton beam from LAMPF. A 10.2-cm diam by 15.2-cm thick NE110 proton recoil detector was used at a flight path of 32 meters, giving a time-of-flight resolution of 60 ps/m. The total cross section results are compared to ENDF/BV evaluations and to previous data where possible

  20. Elliptical cross section fuel rod study II

    International Nuclear Information System (INIS)

    Taboada, H.; Marajofsky, A.

    1996-01-01

    In this paper it is continued the behavior analysis and comparison between cylindrical fuel rods of circular and elliptical cross sections. Taking into account the accepted models in the literature, the fission gas swelling and release were studied. An analytical comparison between both kinds of rod reveals a sensible gas release reduction in the elliptical case, a 50% swelling reduction due to intragranular bubble coalescence mechanism and an important swelling increase due to migration bubble mechanism. From the safety operation point of view, for the same linear power, an elliptical cross section rod is favored by lower central temperatures, lower gas release rates, greater gas store in ceramic matrix and lower stored energy rates. (author). 6 refs., 8 figs., 1 tab

  1. Cross section of the CMS solenoid

    CERN Multimedia

    Tejinder S. Virdee, CERN

    2005-01-01

    The pictures show a cross section of the CMS solenoid. One can see four layers of the superconducting coil, each of which contains the superconductor (central part, copper coloured - niobium-titanium strands in a copper coating, made into a "Rutherford cable"), surrounded by an ultra-pure aluminium as a magnetic stabilizer, then an aluminium alloy as a mechanical stabilizer. Besides the four layers there is an aluminium mechanical piece that includes pipes that transport the liquid helium.

  2. Cross sections for multistep direct reactions

    International Nuclear Information System (INIS)

    Demetriou, Paraskevi; Marcinkowski, Andrzej; Marianski, Bohdan

    2002-01-01

    Inelastic scattering and charge-exchange reactions have been analysed at energies ranging from 14 to 27 MeV using the modified multistep direct reaction theory (MSD) of Feshbach, Kerman and Koonin. The modified theory considers the non-DWBA matrix elements in the MSD cross section formulae and includes both incoherent particle-hole excitations and coherent collective excitations in the continuum, according to the prescriptions. The results show important contributions from multistep processes at all energies considered. (author)

  3. Fully double-logarithm-resummed cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Albino, S.; Bolzoni, P.; Kniehl, B.A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Kotikov, A. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Joint Inst. of Nuclear Research, Moscow (Russian Federation). Bogoliubov Lab. of Theoretical Physics

    2011-04-15

    We calculate the complete double logarithmic contribution to cross sections for semi-inclusive hadron production in the modified minimal-subtraction (MS) scheme by applying dimensional regularization to the double logarithm approximation. The full double logarithmic contribution to the coefficient functions for inclusive hadron production in electron-positron annihilation is obtained in this scheme for the first time. Our result agrees with all fixed order results in the literature, which extend to next-next-to-leading order. (orig.)

  4. Fully double-logarithm-resummed cross sections

    International Nuclear Information System (INIS)

    Albino, S.; Bolzoni, P.; Kniehl, B.A.; Kotikov, A.; Joint Inst. of Nuclear Research, Moscow

    2011-04-01

    We calculate the complete double logarithmic contribution to cross sections for semi-inclusive hadron production in the modified minimal-subtraction (MS) scheme by applying dimensional regularization to the double logarithm approximation. The full double logarithmic contribution to the coefficient functions for inclusive hadron production in electron-positron annihilation is obtained in this scheme for the first time. Our result agrees with all fixed order results in the literature, which extend to next-next-to-leading order. (orig.)

  5. Inclusive jet cross section at D0

    International Nuclear Information System (INIS)

    Bhattacharjee, M.

    1996-09-01

    Preliminary measurement of the central (|η| ≤ 0.5) inclusive jet cross sections for jet cone sizes of 1.0, 0.7, and 0.5 at D null based on the 1992-1993 (13.7 pb -1 ) and 1994-1995 (90 pb -1 ) data samples are presented. Comparisons to Next-to-Leading Order (NLO) Quantum Chromodynamics (QCD) calculations are made

  6. Measurements of Fission Cross Sections of Actinides

    CERN Multimedia

    Wiescher, M; Cox, J; Dahlfors, M

    2002-01-01

    A measurement of the neutron induced fission cross sections of $^{237}$Np, $^{241},{243}$Am and of $^{245}$Cm is proposed for the n_TOF neutron beam. Two sets of fission detectors will be used: one based on PPAC counters and another based on a fast ionization chamber (FIC). A total of 5x10$^{18}$ protons are requested for the entire fission measurement campaign.

  7. K+ nucleus total cross section experiment and nuclear medium effects

    International Nuclear Information System (INIS)

    Weiss, Ruth.

    1992-11-01

    The low momentum K + is the weakest of the available strongly interacting particles. It has a mean bee path in nuclear matter of about 6 fm which makes it a good probe for studying properties of the nuclear interior. It allows one to build a good microscopic optical potential which can be used to calculate K + nucleus elastic and total cross sections. In the latter case the calculated ratio R T =[σ tot (K + A)/A]/[σ tot (K + d)/2] can be expected to be more reliable because some uncertainties in K + N phase shifts will cancel. This ratio can also be measured more reliably than the total cross sections themselves because of cancellation of some systematic errors. We measured the total cross sections of K + on D, 6 Li, 12 C, 28 Si and 40 Ca from 488 to 714 MeV/c. The emphasis was placed on extracting values of R T with a precision of better than 2 percent. The total cross section ratios are found to lie significantly above those predicted by optical potential calculations with the usual nuclear medium corrections. This suggests that novel phenomena are taking place within the nucleus. Several models which incorporate such phenomena are discussed, including nucleon 'swelling', mass rescaling, nuclear pions, and relativistic effects. (author) 31 refs., 27 figs., 21 tabs.,

  8. MXS cross-section preprocessor user's manual

    International Nuclear Information System (INIS)

    Parker, F.; Ishikawa, M.; Luck, L.

    1987-03-01

    The MXS preprocessor has been designed to reduce the execution time of programs using isotopic cross-section data and to both reduce the execution time and improve the accuracy of shielding-factor interpolation in the SIMMER-II accident analysis program. MXS is a dual-purpose preprocessing code to: (1) mix isotopes into materials and (2) fit analytic functions to the shelf-shielding data. The program uses the isotope microscopic neutron cross-section data from the CCCC standard interface file ISOTXS and the isotope Bondarenko self-shielding data from the CCCC standard interface file BRKOXS to generate cross-section and self-shielding data for materials. The materials may be a mixture of several isotopes. The self-shielding data for the materials may be the actual shielding factors or a set of coefficients for functions representing the background dependence of the shielding factors. A set of additional data is given to describe the functions necessary to interpolate the shielding factors over temperature

  9. Neutron capture cross sections of Kr

    Science.gov (United States)

    Fiebiger, Stefan; Baramsai, Bayarbadrakh; Couture, Aaron; Krtička, Milan; Mosby, Shea; Reifarth, René; O'Donnell, John; Rusev, Gencho; Ullmann, John; Weigand, Mario; Wolf, Clemens

    2018-01-01

    Neutron capture and β- -decay are competing branches of the s-process nucleosynthesis path at 85Kr [1], which makes it an important branching point. The knowledge of its neutron capture cross section is therefore essential to constrain stellar models of nucleosynthesis. Despite its importance for different fields, no direct measurement of the cross section of 85Kr in the keV-regime has been performed. The currently reported uncertainties are still in the order of 50% [2, 3]. Neutron capture cross section measurements on a 4% enriched 85Kr gas enclosed in a stainless steel cylinder were performed at Los Alamos National Laboratory (LANL) using the Detector for Advanced Neutron Capture Experiments (DANCE). 85Kr is radioactive isotope with a half life of 10.8 years. As this was a low-enrichment sample, the main contaminants, the stable krypton isotopes 83Kr and 86Kr, were also investigated. The material was highly enriched and contained in pressurized stainless steel spheres.

  10. Measurement of actinide neutron cross sections

    International Nuclear Information System (INIS)

    Firestone, Richard B.; Nitsche, Heino; Leung, Ka-Ngo; Perry, DaleL.; English, Gerald

    2003-01-01

    The maintenance of strong scientific expertise is critical to the U.S. nuclear attribution community. It is particularly important to train students in actinide chemistry and physics. Neutron cross-section data are vital components to strategies for detecting explosives and fissile materials, and these measurements require expertise in chemical separations, actinide target preparation, nuclear spectroscopy, and analytical chemistry. At the University of California, Berkeley and the Lawrence Berkeley National Laboratory we have trained students in actinide chemistry for many years. LBNL is a leader in nuclear data and has published the Table of Isotopes for over 60 years. Recently, LBNL led an international collaboration to measure thermal neutron capture radiative cross sections and prepared the Evaluated Gamma-ray Activation File (EGAF) in collaboration with the IAEA. This file of 35, 000 prompt and delayed gamma ray cross-sections for all elements from Z=1-92 is essential for the neutron interrogation of nuclear materials. LBNL has also developed new, high flux neutron generators and recently opened a 1010 n/s D+D neutron generator experimental facility

  11. Radar cross section measurements using terahertz waves

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Heiselberg, Henning; Jepsen, Peter Uhd

    2010-01-01

    Radar cross sections at terahertz frequencies are measured on scale models of aircrafts. A time domain broadband THz system generates freely propagating THz pulses measured with sub-picosecond time resolution. The THz radiation is generated using fs laser pulses by optical rectification in a lith......Radar cross sections at terahertz frequencies are measured on scale models of aircrafts. A time domain broadband THz system generates freely propagating THz pulses measured with sub-picosecond time resolution. The THz radiation is generated using fs laser pulses by optical rectification...... in a lithium niobate crystal with application of the tilted wave front method, resulting in high electric field THz pulses with a broad band spectrum from 100 GHz up to 4 THz. The corresponding wave lengths are two orders of magnitude smaller than normal radars and we therefore use scale models of size 5-10 cm...... in order to measure realistic radar cross sections. RCS polar and azimuthal angle plots of F-16 and F-35 are presented....

  12. Neutron capture cross sections of Kr

    Directory of Open Access Journals (Sweden)

    Fiebiger Stefan

    2017-01-01

    Full Text Available Neutron capture and β− -decay are competing branches of the s-process nucleosynthesis path at 85Kr [1], which makes it an important branching point. The knowledge of its neutron capture cross section is therefore essential to constrain stellar models of nucleosynthesis. Despite its importance for different fields, no direct measurement of the cross section of 85Kr in the keV-regime has been performed. The currently reported uncertainties are still in the order of 50% [2, 3]. Neutron capture cross section measurements on a 4% enriched 85Kr gas enclosed in a stainless steel cylinder were performed at Los Alamos National Laboratory (LANL using the Detector for Advanced Neutron Capture Experiments (DANCE. 85Kr is radioactive isotope with a half life of 10.8 years. As this was a low-enrichment sample, the main contaminants, the stable krypton isotopes 83Kr and 86Kr, were also investigated. The material was highly enriched and contained in pressurized stainless steel spheres.

  13. ENDF Cross Sections are not Uniquely Defined

    Energy Technology Data Exchange (ETDEWEB)

    Cullen, D. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2010-06-11

    Most evaluated data that is coded into the ENDF format [1] does not uniquely define cross sections, because the evaluator defined total is not equal to the sum of evaluator defined partial cross sections, i.e., the total is not equal to elastic plus capture, etc. So we have always had the question: What is the correct total cross section? This is not a new problem; it has existed since the very beginning of ENDF over forty years ago. It is a problem that is periodically discussed and apparently handled, only to have it pop up again every ten years or so, as we have the next generation of ENDF format users who are not aware of the problem. See the Appendices for a summary of the differences that exist today for the ENDF/B-VII.0 (Appendix C), JEFF- 3.1(Appendix D), JENDL-3.3 (Appendix E), and CENDL-3.1 (Appendix F) data libraries. For use in our application we need consistent, unique data. To accomplish this for decades we [2, 3] have been ignoring the evaluator defined total, and re-defining it as equal to the sum of its evaluator defined parts. This has never been completely satisfactory to us, because we have been doing this without consulting evaluators, or obtaining their approval, so that the data we actually use in our applications may or may not be what the evaluators intended.

  14. Antineutrino-nucleon total cross section and ratio of antineutrino cross section on neutrons and protons

    CERN Document Server

    Erriquez, O; Bisi, V; Bonetti, S; Bullock, F W; Cavalli, D; Engel, J P; Eranzinetti, C; Escubes, B; Esten, M J; Fogli-Muciaccia, M T; Gamba, D; Guyonnet, J L; Halsteinslid, A; Henderson, R C W; Huss, D; Jones, T W; Marzari-Chiesa, A; Mauri, F; Myklebost, K; Natali, S; Nuzzo, S; Paty, M; Pullia, A; Racca, C; Ramzan, F A; Riccati, L; Riester, J L; Rognebakke, A; Rollier, M; Romero, A; Skjeggestad, O

    1979-01-01

    On a selected sample of 2171 events, observed in the heavy liquid bubble chamber Gargamelle at CERN, the charged current total cross section for antineutrino on nucleons has been determined to the laboratory energy 8 GeV. (7 refs).

  15. Cross sections of deuteron induced nuclear reactions on metal targets

    International Nuclear Information System (INIS)

    Tarkanyi, F.; Ditroi, F.; Takacs, S.

    2005-01-01

    Integral excitation functions for the production of residual nuclides with light charged particles are basic data for different applications. The proton induced nuclear reactions are the most widely used and their cross section data are extensively studied. For practical applications these reactions are followed in importance by deuteron induced reactions. Due to the stripping process the production yield of the deuteron induced reactions is significant. High intensity deuteron beams can be produced relatively simply by accelerators. Deuteron induced reactions play an important role in secondary fast neutron sources, in thin layer activation technology, etc. The search of the literature shows that the cross section database for deuteron induced reactions is very poor (very few data above 15-20 MeV). No systematical study has been performed earlier. In addition the published data (except for a few well measured monitor and medically important reactions) show large discrepancies. To meet the requirements of these applications we performed a systematical experimental study of deuteron induced activation cross sections for different targets up to 50 MeV deuteron energy during the last years. Here we summarize the results for the most widely used technological materials: i.e. for metals. The targets were irradiated with external beams of the cyclotrons of Debrecen, Brussels and Sendai, Residual nuclei were measured by X- and gamma-spectrometry without chemical separation. The investigation includes a few hundred reactions induced on the following 20 target elements: Al, Ti, Fe, Ni, Cu, Zn, Y, Zr, Nb, Mo, Rh, Pd, Ag, Cd, Sn, Te, W, Ir, Pt, Pb. A significant part of the measured data is new. The measured excitation functions were compared with the theory by using the ALICE-IPPE and TALYS codes. For a few elements, isotopic cross sections were measured on highly enriched targets ( 100 Mo, 122,123 Te, 114 Cd) for medical radioisotope production Applications in the field of

  16. Mechanized evaluation of neutron cross-sections

    International Nuclear Information System (INIS)

    Horsley, A.; Parker, J.B.

    1967-01-01

    The evaluation work to provide accurate and consistent neutron cross-section data for multigroup neutronics calculations is not fully exploiting the available theoretical and experimental results; this has been so particularly since the introduction of on-line data handling techniques enabled experimenters to turn out vast quantities of numbers. This situation can be radically improved only by mechanizing the evaluation processes. Systems such as the SC1SRS tape will not only largely overcome the task of collecting data but will provide speedy access to it; by using computers and graph-plotting machines to tabulate and display this data, the labour of evaluation can be very greatly reduced. With some types of cross-section there is hope that by using modern curve-fitting techniques the actual evaluation and statistical accounting of the data can be performed automatically. Some areas where automatic evaluation would seem likely to succeed are specified and a discussion of the mathematical difficulties incurred, such as the elimination of anomalous data, is given. Particularly promising is the use of splines in the mechanized evaluation of data. Splines are the mathematical analogues of the draughtsman's spline used in drawing smooth curves. Their principal properties are the excellent approximations they give to the derivatives of a function; in contrast to conventional polynomial fitting, this feature ensures good interpolation and, when required, stable extrapolation. Various methods of using splines in data graduation and the problem of marrying these methods to standard statistical procedures are examined. The results of work done at AWRE with cubic splines on the mechanized evaluation of neutron scattering total cross-section and angular distribution data are presented. (author)

  17. Neutron capture cross section of $^{93}$Zr

    CERN Multimedia

    We propose to measure the neutron capture cross section of the radioactive isotope $^{93}$Zr. This project aims at the substantial improvement of existing results for applications in nuclear astrophysics and emerging nuclear technologies. In particular, the superior quality of the data that can be obtained at n_TOF will allow on one side a better characterization of s-process nucleosynthesis and on the other side a more accurate material balance in systems for transmutation of nuclear waste, given that this radioactive isotope is widely present in fission products.

  18. Fission cross section measurements for minor actinides

    Energy Technology Data Exchange (ETDEWEB)

    Fursov, B. [IPPE, Obninsk (Russian Federation)

    1997-03-01

    The main task of this work is the measurement of fast neutron induced fission cross section for minor actinides of {sup 238}Pu, {sup 242m}Am, {sup 243,244,245,246,247,248}Cm. The task of the work is to increase the accuracy of data in MeV energy region. Basic experimental method, fissile samples, fission detectors and electronics, track detectors, alpha counting, neutron generation, fission rate measurement, corrections to the data and error analysis are presented in this paper. (author)

  19. LEP vacuum chamber, cross-section

    CERN Multimedia

    CERN PhotoLab

    1983-01-01

    Cross-section of the final prototype for the LEP vacuum chamber. The elliptic main-opening is for the beam. The small channel to the left is for the cooling water, to carry away the heat deposited by the synchrotron radiation. The square channel to the right houses the Non-Evaporable Getter (NEG) pump. The chamber is made from extruded aluminium. Its outside is clad with lead, to stop the synchrotron radiation emitted by the beam. For good adherence between Pb and Al, the Al chamber was coated with a thin layer of Ni. Ni being slightly magnetic, some resulting problems had to be overcome. See also 8301153.

  20. Measurement of thermal neutron capture cross section

    International Nuclear Information System (INIS)

    Huang Xiaolong; Han Xiaogang; Yu Weixiang; Lu Hanlin; Zhao Wenrong

    2001-01-01

    The thermal neutron capture cross sections of 71 Ga(n, γ) 72 Ga, 94 Zr(n, γ) 95 Zr and 191 Ir(n, γ) 192 Ir m1+g,m2 reactions were measured by using activation method and compared with other measured data. Meanwhile the half-life of 72 Ga was also measured. The samples were irradiated with the neutron in the thermal column of heavy water reactor of China Institute of Atomic Energy. The activities of the reaction products were measured by well-calibrated Ge(Li) detector

  1. Empirical continuation of the differential cross section

    International Nuclear Information System (INIS)

    Borbely, I.

    1978-12-01

    The theoretical basis as well as the practical methods of empirical continuation of the differential cross section into the nonphysical region of the cos theta variable are discussed. The equivalence of the different methods is proved. A physical applicability condition is given and the published applications are reviewed. In many cases the correctly applied procedure turns out to provide nonsignificant or even incorrect structure information which points to the necessity for careful and statistically complete analysis of the experimental data with a physical understanding of the analysed process. (author)

  2. Pion production cross sections and associated parameters

    International Nuclear Information System (INIS)

    Bradbury, J.N.

    1985-01-01

    Negative pions have been used for radiotherapy at the meson factories LAMPF (USA), SIN (Switzerland), and TRIUMF (Canada) and have been planned for use at new meson facilities under construction (USSR) and at proposed dedicated medical facilities. Providing therapeutically useful dose rates of pions requires a knowledge of the pion production cross sections as a function of primary proton energy (500 to 1000 MeV), pion energy (less than or equal to100 MeV), production angle, and target material. The current status of the data base in this area is presented including theoretical guidelines for extrapolation purposes. The target material and geometry, as well as the proton and pion beam parameters, will affect the electron (and muon) contamination in the beam which may have an important effect on both the LET characteristics of the dose and the dose distribution. In addition to cross-section data, channel characteristics such as length of pion trajectory, solid-angle acceptance, and momentum analysis will affect dose rate, distribution, and quality. Such considerations are briefly addressed in terms of existing facilities and proposed systems. 16 refs., 6 figs

  3. Calculation of cross sections for heavy isotopes

    International Nuclear Information System (INIS)

    Caner, M.

    1976-04-01

    In the present work an integrated system of codes for basic neutron data evaluation were assembled and built. Complete evaluations for the isotopes 240 Pu, 241 Pu, 242 Pu and 238 Pu were performed. The following cross sections: total, elastic, radiative capture, fission, total inelastic, partial inelastic, (n,2n), (n,3n) and differential elastic were evaluated as well as the average number of neutrons per neutron-induced fission and the average elastic scattering cosine in the lab system.The data for the plutonium isotopes were incorporated into the German KEDAK file. A method was developed for calculating the energy distributions of the second and third secondary neutrons from the A(n,2n) and (n,3n) reactions in the framework of the compound nucleus theory, and utilizing the nuclear data of the nuclei A, A-1, A-2. This method was used to generate the 238 U secondary neutron energy distributions in the incident neutron energy range of 6 to 15 MeV. A nuclear data evaluation for 237 U in the resolved inelastic scattering range (10-700 keV) was performed. The compound elastic and partial inelastic scattering cross sections were used in the 238 U secondary neutron energy distribution calculations. (B.G.)

  4. Compilation of electron collision excitation cross sections for neutro argon

    International Nuclear Information System (INIS)

    Blanco Ramos, F.

    1993-01-01

    The present work presents a compilation and critical analysis of the available data on electron collision excitation cross sections for neutral Argon levels. This study includes: 1.- A detailed description in intermediate coupling for all the levels belonging the 20 configurations 3p''5 ns(n=4 to 12), np(n=4 to 8) and nd(n=3 to 8) of neutral Argon. 2.- Calculation of the electron collision excitation cross sections in Born and Born-Oppenheimer-Ochkur approximations for all the levels in the 14 configurations 3p''5 ns(n=4 to 7), np(n=4 to 7) and nd(n=3 to 8). 3.- Comparison and discussion of the compiled data. These are the experimental and theoretical values available from the literature, and those from this work. 4.- Analysis of the regularities and systematic behaviors in order to determine which values can be considered more reliable. It is show that the concept of one electron cross section results quite useful for this purpose. In some cases it has been possible to obtain in this way approximate analytical expressions interpolating the experimental data. 5.- All the experimental and theoretical values studied are graphically presented and compared. 6.- The last part of the work includes a listing of several general purpose programs for Atomic Physics calculations developed for this work. (Author)

  5. Compilation of electron collision excitation cross sections for neutral argon

    International Nuclear Information System (INIS)

    Blanco, F.

    1993-01-01

    The present work presents a compilation and critical analysis of the available data on electron collision excitation cross sections for neutral Argon levels. This study includes: 1.- A detailed description in intermediate coupling for all the levels belonging the 20 configurations 3p5 ns (n=4to 12), np(n=4to8) and nd(n=3to8)of neutral Argon. 2.- Calculation of the electron collision excitation cross sections in Born and Born-Oppenheimer-Ochkur approximations for all the levels in the 14 configurations 3p5 ns (n=4 to 7), np (n=4 to 7) and nd (n=3 to 8). 3.- comparison and discussion of the compiled data. These are the experimental and theoretical values available from the literature, and those from this work. 4.- Analysis of the regularities and systematic behaviors in order to determine which values can be considered more reliable. It is show that the concept of one electron cross section results quite useful for this purpose. In some cases it has been possible to obtain in this way approximate analytical expressions interpolating the experimental data. 5.- All the experimental and theoretical values studied are graphically presented and compared. 6.- The last part of the work includes a listing of several general purpose programs for Atomic Physics calculations developed for this work. (Author) 35 refs

  6. Differences between LASL- and ANL-processed cross sections

    International Nuclear Information System (INIS)

    Kidman, R.B.; MacFarlane, R.E.; Becker, M.

    1978-03-01

    As part of the Los Alamos Scientific Laboratory (LASL) cross-section processing development, LASL cross sections and results from MINX/1DX system are compared to the Argonne National Laboratory cross sections and results from the ETOE-2/MC 2 -2 system for a simple reactor problem. Exact perturbation theory is used to establish the eigenvalue effect of every isotope group cross-section difference. Cross sections, cross-section differences, and their eigenvalue effects are clearly and conveniently displayed and compared on a group-by-group basis

  7. Cross section homogenization analysis for a simplified Candu reactor

    International Nuclear Information System (INIS)

    Pounders, Justin; Rahnema, Farzad; Mosher, Scott; Serghiuta, Dumitru; Turinsky, Paul; Sarsour, Hisham

    2008-01-01

    The effect of using zero current (infinite medium) boundary conditions to generate bundle homogenized cross sections for a stylized half-core Candu reactor problem is examined. Homogenized cross section from infinite medium lattice calculations are compared with cross sections homogenized using the exact flux from the reference core environment. The impact of these cross section differences is quantified by generating nodal diffusion theory solutions with both sets of cross sections. It is shown that the infinite medium spatial approximation is not negligible, and that ignoring the impact of the heterogeneous core environment on cross section homogenization leads to increased errors, particularly near control elements and the core periphery. (authors)

  8. Classifications for cesarean section: a systematic review.

    Directory of Open Access Journals (Sweden)

    Maria Regina Torloni

    Full Text Available BACKGROUND: Rising cesarean section (CS rates are a major public health concern and cause worldwide debates. To propose and implement effective measures to reduce or increase CS rates where necessary requires an appropriate classification. Despite several existing CS classifications, there has not yet been a systematic review of these. This study aimed to 1 identify the main CS classifications used worldwide, 2 analyze advantages and deficiencies of each system. METHODS AND FINDINGS: Three electronic databases were searched for classifications published 1968-2008. Two reviewers independently assessed classifications using a form created based on items rated as important by international experts. Seven domains (ease, clarity, mutually exclusive categories, totally inclusive classification, prospective identification of categories, reproducibility, implementability were assessed and graded. Classifications were tested in 12 hypothetical clinical case-scenarios. From a total of 2948 citations, 60 were selected for full-text evaluation and 27 classifications identified. Indications classifications present important limitations and their overall score ranged from 2-9 (maximum grade =14. Degree of urgency classifications also had several drawbacks (overall scores 6-9. Woman-based classifications performed best (scores 5-14. Other types of classifications require data not routinely collected and may not be relevant in all settings (scores 3-8. CONCLUSIONS: This review and critical appraisal of CS classifications is a methodologically sound contribution to establish the basis for the appropriate monitoring and rational use of CS. Results suggest that women-based classifications in general, and Robson's classification, in particular, would be in the best position to fulfill current international and local needs and that efforts to develop an internationally applicable CS classification would be most appropriately placed in building upon this

  9. Classifications for cesarean section: a systematic review.

    Science.gov (United States)

    Torloni, Maria Regina; Betran, Ana Pilar; Souza, Joao Paulo; Widmer, Mariana; Allen, Tomas; Gulmezoglu, Metin; Merialdi, Mario

    2011-01-20

    Rising cesarean section (CS) rates are a major public health concern and cause worldwide debates. To propose and implement effective measures to reduce or increase CS rates where necessary requires an appropriate classification. Despite several existing CS classifications, there has not yet been a systematic review of these. This study aimed to 1) identify the main CS classifications used worldwide, 2) analyze advantages and deficiencies of each system. Three electronic databases were searched for classifications published 1968-2008. Two reviewers independently assessed classifications using a form created based on items rated as important by international experts. Seven domains (ease, clarity, mutually exclusive categories, totally inclusive classification, prospective identification of categories, reproducibility, implementability) were assessed and graded. Classifications were tested in 12 hypothetical clinical case-scenarios. From a total of 2948 citations, 60 were selected for full-text evaluation and 27 classifications identified. Indications classifications present important limitations and their overall score ranged from 2-9 (maximum grade =14). Degree of urgency classifications also had several drawbacks (overall scores 6-9). Woman-based classifications performed best (scores 5-14). Other types of classifications require data not routinely collected and may not be relevant in all settings (scores 3-8). This review and critical appraisal of CS classifications is a methodologically sound contribution to establish the basis for the appropriate monitoring and rational use of CS. Results suggest that women-based classifications in general, and Robson's classification, in particular, would be in the best position to fulfill current international and local needs and that efforts to develop an internationally applicable CS classification would be most appropriately placed in building upon this classification. The use of a single CS classification will facilitate

  10. Calculated cross sections for elastic scattering of slow positrons by silane

    Science.gov (United States)

    Barbosa, Alessandra Souza; Bettega, Márcio H. F.

    2017-10-01

    In this work we investigate elastic collisions of low-energy positrons with silane (SiH4). We employed the Schwinger multichannel method to calculate integral and differential cross sections for impact energies up to 10 eV. The calculations were performed within the static plus polarization approximation. We carried out a systematic study employing different schemes to account for the polarization effects of the target due the presence of the incoming positron. We investigate how the inclusion of extra functions in different extra (chargeless) centers affects the calculated cross sections and the physical phenomena such as the Ramsauer-Townsend minimum and the virtual state formation. Our results are compared with available experimental total cross sections and with integral and differential cross sections computed with a model correlation-polarization potential. In particular, our integral cross section agrees well with the experiment at low energies and our differential cross sections agree well with the results from previous calculations.

  11. Topological supersymmetric structure of hadron cross sections

    International Nuclear Information System (INIS)

    Gauron, P.; Nicolescu, B.; Ouvry, S.

    1980-12-01

    Recently a way of fully implementing unitarity in the framework of a Dual Topological Unitarization theory, including not only mesons but also baryons, was found. This theory consists in the topological description of hadron interactions involving confined quarks in terms of two 2-dimensional surfaces (a closed 'quantum' surface and a bounded 'classical' surface). We show that this description directly leads, at the zeroth order of the topological expansion, to certain relations between hadron cross-sections, in nice agreement with experimental data. A new topological suppression mechanism is shown to play an important dynamical role. We also point out a new topological supersymmetry property, which leads to realistic experimental consequences. A possible topological origin of the rho and ω universality relations emerges as a by-product of our study

  12. Partial cross sections in H- photodetachment

    International Nuclear Information System (INIS)

    Halka, M.

    1993-04-01

    This dissertation reports experimental measurements of partial decay cross sections in the H - photodetachment spectrum. Observed decays of the 1 P 0 H -** (n) doubly-excitedresonances to the H(N=2) continuum are reported for n=2,3, and 4 from 1990 runs in which the author participated. A recent analysis of 1989 data revealing effects of static electric fields on the partial decay spectrum above 13.5 eV is also presented. The experiments were performed at the High Resolution Atomic Beam Facility. the Los Alamos Meson Physics Facility, with a relativistic H - beam (β=0.842)intersecting a ND:YAG laser. Variation of the intersection angle amounts to Doppler-shifting the photon energy, allowing continuous tuning of the laser energy as viewed from the moving ions' frame

  13. Angle-averaged Compton cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Nickel, G.H.

    1983-01-01

    The scattering of a photon by an individual free electron is characterized by six quantities: ..cap alpha.. = initial photon energy in units of m/sub 0/c/sup 2/; ..cap alpha../sub s/ = scattered photon energy in units of m/sub 0/c/sup 2/; ..beta.. = initial electron velocity in units of c; phi = angle between photon direction and electron direction in the laboratory frame (LF); theta = polar angle change due to Compton scattering, measured in the electron rest frame (ERF); and tau = azimuthal angle change in the ERF. We present an analytic expression for the average of the Compton cross section over phi, theta, and tau. The lowest order approximation to this equation is reasonably accurate for photons and electrons with energies of many keV.

  14. Plasma-based radar cross section reduction

    CERN Document Server

    Singh, Hema; Jha, Rakesh Mohan

    2016-01-01

    This book presents a comprehensive review of plasma-based stealth, covering the basics, methods, parametric analysis, and challenges towards the realization of the idea. The concealment of aircraft from radar sources, or stealth, is achieved through shaping, radar absorbing coatings, engineered materials, or plasma, etc. Plasma-based stealth is a radar cross section (RCS) reduction technique associated with the reflection and absorption of incident electromagnetic (EM) waves by the plasma layer surrounding the structure. A plasma cloud covering the aircraft may give rise to other signatures such as thermal, acoustic, infrared, or visual. Thus it is a matter of concern that the RCS reduction by plasma enhances its detectability due to other signatures. This needs a careful approach towards the plasma generation and its EM wave interaction. The book starts with the basics of EM wave interactions with plasma, briefly discuss the methods used to analyze the propagation characteristics of plasma, and its generatio...

  15. Differential cross section of atomic hydrogen photoionization

    International Nuclear Information System (INIS)

    Kondratovich, V.D.; Ostrovskij, V.N.

    1986-01-01

    Differential cross-section of atomic hydrogen photoeffect in external electric field was investigated in semiclassical approximation. Interference was described. It occurred due to the fact that infinite number of photoelectron trajectories leads to any point of classically accessible motion region. Interference picture can reach macroscopic sizes. The picture is determined by location of function nodes, describing finite electron motion along one of parabolic coordinates. The squares of external picture rings are determined only by electric field intensity in the general case at rather high energies. Quantum expression for photocurrent density was obtained using Green function in superposition of Coulomb and uniform field as well as semiclassical approximation. Possible applications of macroscopic interference picture to specification of atom ionization potentials, selective detection of atoms or particular molecules, as well as weak magnetic field and observation of Aaronov-Bom effect are discussed

  16. K sup + nucleus total cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Sawafta, R.

    1990-01-01

    The scattering of K{sup +} mesons from nuclei has attracted considerable interest in the last few years. The K{sup +} holds a very special position as the weakest of all strongly interaction probes. The average cross section is not larger than about 10 mb at lab momenta below 800 MeV/c, corresponding to a mean free path in the nucleus larger than 5 fm. Thus the K{sup +} is capable of probing the entire volume of the nucleus. Single scattering of the K{sup +} with a nucleon in the nucleus dominates the nuclear scattering, and only small and calculable higher order corrections are needed. The nucleon is a dynamical entity and its internal structure can, in principle, be altered by its surrounding nuclear environment. This work reports an experiment in which the K{sup +} is used to compare the nucleon in the nucleus with a free nucleon.

  17. ISSUES IN NEUTRON CROSS SECTION COVARIANCES

    Energy Technology Data Exchange (ETDEWEB)

    Mattoon, C.M.; Oblozinsky,P.

    2010-04-30

    We review neutron cross section covariances in both the resonance and fast neutron regions with the goal to identify existing issues in evaluation methods and their impact on covariances. We also outline ideas for suitable covariance quality assurance procedures.We show that the topic of covariance data remains controversial, the evaluation methodologies are not fully established and covariances produced by different approaches have unacceptable spread. The main controversy is in very low uncertainties generated by rigorous evaluation methods and much larger uncertainties based on simple estimates from experimental data. Since the evaluators tend to trust the former, while the users tend to trust the latter, this controversy has considerable practical implications. Dedicated effort is needed to arrive at covariance evaluation methods that would resolve this issue and produce results accepted internationally both by evaluators and users.

  18. Total Neutron Cross Section Instrumentation at UML

    Science.gov (United States)

    Seo, P.-N.; Egan, J. J.; Kegel, G. H. R.; Mittler, A.; Tedesco, J.

    1997-10-01

    The UML type CN Van de Graaff accelerator incorporates a terminal pulsing system operating at 5 MHz. Proton bursts are Mobley-compressed to subnanosecond durations. When used with a thick metallic Li target, a pulsed pseudo-white neutron spectrum is produced suitable for neutron total cross section measurements. The spectrum is characterized by its sharp high energy cut-off, e.g. at 500 keV. Precautions are necessary because neutrons of different energies are recorded in the same time bin if their flight times differ by 200 ns. Pulse height discrimination may be used to eliminate lower energy neutrons; this is inefficient because higher energy neutron signals are also eliminated, to some degree. Two-dimensional data acquisition is the preferred approach. We review two systems of this type and we describe the system in use at UML.

  19. Angle-averaged Compton cross sections

    International Nuclear Information System (INIS)

    Nickel, G.H.

    1983-01-01

    The scattering of a photon by an individual free electron is characterized by six quantities: α = initial photon energy in units of m 0 c 2 ; α/sub s/ = scattered photon energy in units of m 0 c 2 ; β = initial electron velocity in units of c; phi = angle between photon direction and electron direction in the laboratory frame (LF); theta = polar angle change due to Compton scattering, measured in the electron rest frame (ERF); and tau = azimuthal angle change in the ERF. We present an analytic expression for the average of the Compton cross section over phi, theta, and tau. The lowest order approximation to this equation is reasonably accurate for photons and electrons with energies of many keV

  20. Sudakov resummation of multiparton QCD cross sections

    CERN Document Server

    Bonciani, R; Mangano, Michelangelo L; Nason, P

    2003-01-01

    We present the general expressions for the resummation, up to next-to-leading logarithmic accuracy, of Sudakov-type logarithms in processes with an arbirtrary number of hard-scattering partons. These results document the formulae used by the authors in several previous phenomenological studies. The resummation formulae presented here, which are valid for phase-space factorizable observables, determine the resummation correction in a process-independent fashion. All process dependence is encoded in the colour and flavour structure of the leading order and virtual one-loop amplitudes, and in Sudakov weights associated to the cross section kinematics. We explicitly illustrate the application to the case of Drell--Yan and prompt-photon production.

  1. Chronic malnutrition: a cross-section analysis

    Directory of Open Access Journals (Sweden)

    Emely Beatriz García González

    2014-01-01

    Full Text Available ABSTRACT Introduction: The objective of the study was to determine the main causes of chronic malnutrition worldwide. Materials and Methods: A cross-sectional study was employed to analyze the main determinants of chronic malnutrition in a sample of 86 countries. The variables used are based on the UNICEF conceptual framework of malnutrition. This framework classifies the determinants of malnutrition in three main causes: basic, immediate, and underlying. Findings: Droughts, floods, and extreme temperatures, and GDP per capita are the main basic determinants of malnutrition in the sample of countries. In addition one underlying determinant had a major impact in the prevalence of malnutrition: improved sanitation facilities. Conclusions: The findings of this study demonstrated that the variables within the basic and underlying cause classification are the ones with a greater impact on chronic malnutrition.

  2. Chronic malnutrition: a cross-section analysis

    Directory of Open Access Journals (Sweden)

    Emely Beatriz García González

    2014-01-01

    Full Text Available Introduction: The objective of the study was to determine the main causes of chronic malnutrition worldwide. Materials and Methods: A cross-sectional study was employed to analyze the main determinants of chronic malnutrition in a sample of 86 countries. The variables used are based on the UNICEF conceptual framework of malnutrition. This framework classifies the determinants of malnutrition in three main causes: basic, immediate, and underlying. Findings: Droughts, floods, and extreme temperatures, and GDP per capita are the main basic determinants of malnutrition in the sample of countries. In addition one underlying determinant had a major impact in the prevalence of malnutrition: improved sanitation facilities. Conclusions: The findings of this study demonstrated that the variables within the basic and underlying cause classification are the ones with a greater impact on chronic malnutrition.

  3. Neutron scattering cross sections of uranium-238

    International Nuclear Information System (INIS)

    Beghian, L.E.; Kegel, G.H.R.; Marcella, T.V.; Barnes, B.K.; Couchell, G.P.; Egan, J.J.; Mittler, A.; Pullen, D.J.; Schier, W.A.

    1979-01-01

    The University of Lowell high-resolution time-of-flight spectrometer was used to measure angular distributions and 90-deg excitation functions for neutrons scattered from 238 U in the energy range from 0.9 to 3.1 MeV. This study was limited to the elastic and the first two inelastic groups, corresponding to states of 238 U at 45 keV (2 + ) and 148 keV (4 + ). Angular distributions were measured at primary neutron energies of 1.1, 1.9, 2.5, and 3.1 MeV for the same three neutron groups. Whereas the elastic data are in fair agreement with the evaluation in the ENDF/B-IV file, there is substantial disagreement between the inelastic measurements and the evaluated cross sections. 12 figures

  4. Contribution to uncertainties evaluation for fast reactors neutronic cross sections

    International Nuclear Information System (INIS)

    Privas, Edwin

    2015-01-01

    The thesis has been motivated by a wish to increase the uncertainty knowledge on nuclear data, for safety criteria. It aims the cross sections required by core calculation for sodium fast reactors (SFR), and new tools to evaluate its.The main objective of this work is to provide new tools in order to create coherent evaluated files, with reliable and mastered uncertainties. To answer those problematic, several methods have been implemented within the CONRAD code, which is developed at CEA of Cadarache. After a summary of all the elements required to understand the evaluation world, stochastic methods are presented in order to solve the Bayesian inference. They give the evaluator more information about probability density and they also can be used as validation tools. The algorithms have been successfully tested, despite long calculation time. Then, microscopic constraints have been implemented in CONRAD. They are defined as new information that should be taken into account during the evaluation process. An algorithm has been developed in order to solve, for example, continuity issues between two energy domains, with the Lagrange multiplier formalism. Another method is given by using a marginalization procedure, in order to either complete an existing evaluation with new covariance or add systematic uncertainty on an experiment described by two theories. The algorithms are well performed along examples, such the 238 U total cross section. The last parts focus on the integral data feedback, using methods of integral data assimilation to reduce the uncertainties on cross sections. This work ends with uncertainty reduction on key nuclear reactions, such the capture and fission cross sections of 238 U and 239 Pu, thanks to PROFIL and PROFIL-2 experiments in Phenix and the Jezebel benchmark. (author) [fr

  5. Single-level resonance parameters fit nuclear cross-sections

    Science.gov (United States)

    Drawbaugh, D. W.; Gibson, G.; Miller, M.; Page, S. L.

    1970-01-01

    Least squares analyses of experimental differential cross-section data for the U-235 nucleus have yielded single level Breit-Wigner resonance parameters that fit, simultaneously, three nuclear cross sections of capture, fission, and total.

  6. Resonance capture cross section of 207Pb

    CERN Document Server

    Domingo-Pardo, C.; Aerts, G.; Alvarez-Pol, H.; Alvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Becvar, F.; Berthoumieux, E.; Bisterzo, S.; Calvino, F.; Cano-Ott, D.; Capote, R.; Carrapico, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Colonna, N.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillman, I.; Dolfini, R.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Segura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fitzpatrick, L.; Frais-Koelbl, H.; Fujii, K.; Furman, W.; Gallino, R.; Goncalves, I.; Gonzalez-Romero, E.; Goverdovski, A.; Gramegna, F.; Griesmayer, E.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Isaev, S.; Jericha, E.; Kadi, Y.; Kappeler, F.; Karamanis, D.; Karadimos, D.; Kerveno, M.; Ketlerov, V.; Koehler, P.; Konovalov, V.; Kossionides, E.; Krticka, M.; Lamboudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Mastinu, P.; Mengoni, A.; Milazzo, P.M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; Oshima, M.; O'Brien, S.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rosetti, M.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J.L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M.C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wendler, H.; Wiescher, M.; Wisshak, K.

    2006-01-01

    The radiative neutron capture cross section of 207Pb has been measured at the CERN neutron time of flight installation n_TOF using the pulse height weighting technique in the resolved energy region. The measurement has been performed with an optimized setup of two C6D6 scintillation detectors, which allowed us to reduce scattered neutron backgrounds down to a negligible level. Resonance parameters and radiative kernels have been determined for 16 resonances by means of an R-matrix analysis in the neutron energy range from 3 keV to 320 keV. Good agreement with previous measurements was found at low neutron energies, whereas substantial discrepancies appear beyond 45 keV. With the present results, we obtain an s-process contribution of 77(8)% to the solar abundance of 207Pb. This corresponds to an r-process component of 23(8)%, which is important for deriving the U/Th ages of metal poor halo stars.

  7. Graphs of the cross sections in the recommended Monte Carlo cross-section library at the Los Alamos Scientific Laboratory

    International Nuclear Information System (INIS)

    Soran, P.D.; Seamon, R.E.

    1980-05-01

    Graphs of all neutron cross sections and photon production cross sections on the Recommended Monte Carlo Cross Section (RMCCS) library have been plotted along with local neutron heating numbers. Values for anti ν, the average number of neutrons per fission, are also given

  8. Preparation of next generation set of group cross sections. 3

    International Nuclear Information System (INIS)

    Kaneko, Kunio

    2002-03-01

    This fiscal year, based on the examination result about the evaluation energy range of heavy element unresolved resonance cross sections, the upper energy limit of the energy range, where ultra-fine group cross sections are produced, was raised to 50 keV, and an improvement of the group cross section processing system was promoted. At the same time, reflecting the result of studies carried out till now, a function producing delayed neutron data was added to the general-purpose group cross section processing system , thus the preparation of general purpose group cross section processing system has been completed. On the other hand, the energy structure, data constitution and data contents of next generation group cross section set were determined, and the specification of a 151 groups next generation group cross section set was defined. Based on the above specification, a concrete library format of the next generation cross section set has been determined. After having carried out the above-described work, using the general-purpose group cross section processing system , which was complete in this study, with use of the JENDL-3. 2 evaluated nuclear data, the 151 groups next generation group cross section of 92 nuclides and the ultra fine group resonance cross section library for 29 nuclides have been prepared. Utilizing the 151 groups next generation group cross section set and the ultra-fine group resonance cross-section library, a bench mark test calculation of fast reactors has been performed by using an advanced lattice calculation code. It was confirmed, by comparing the calculation result with a calculation result of continuous energy Monte Carlo code, that the 151 groups next generation cross section set has sufficient accuracy. (author)

  9. Measurement of the antiproton-nucleus annihilation cross-section at low energy

    Science.gov (United States)

    Aghai-Khozani, H.; Bianconi, A.; Corradini, M.; Hayano, R.; Hori, M.; Leali, M.; Lodi Rizzini, E.; Mascagna, V.; Murakami, Y.; Prest, M.; Vallazza, E.; Venturelli, L.; Yamada, H.

    2018-02-01

    Systematic measurements of the annihilation cross sections of low energy antinucleons were performed at CERN in the 80's and 90's. However the antiproton data on medium-heavy and heavy nuclear targets are scarce. The ASACUSA Collaboration at CERN has measured the antiproton annihilation cross section on carbon at 5.3 MeV: the value is (1.73 ± 0.25) barn. The result is compared with the antineutron experimental data and with the theoretical previsions.

  10. Cross-Sections Classes of Structural Steel Members

    Directory of Open Access Journals (Sweden)

    Daniela Preda

    2007-01-01

    Full Text Available Cross-sectional classification, introduced in EUROCODE 3, is destined to comply with any type of cross-section, disregarding the slenderness of cross-sectional wall plates. From practical reasons, this classification refers to cross-sections considered as a general matter. But in the same cross-section, the plates loaded with compression stresses, thus exposed to local buckling can belong to different classes of sections depending upon the loads acting on that cross-section. Furthermore, the stress diagrams corresponding to these cross-sectional plates are themselves closely related to applied loads and they influence directly the degrees of sensitivity to local buckling. On the other hand, the different degrees of sensitivity to local buckling depend on the slenderness of cross-sectional plates. A cross-section is normally classified by quoting the highest (least favourable class of its compression elements. The strength calculation (and general stability of structural members depends on the cross-section classes.

  11. Development of radar cross section analysis system of naval ships

    Science.gov (United States)

    Kim, Kookhyun; Kim, Jin-Hyeong; Choi, Tae-Muk; Cho, Dae-Seung

    2012-03-01

    A software system for a complex object scattering analysis, named SYSCOS, has been developed for a systematic radar cross section (RCS) analysis and reduction design. The system is based on the high frequency analysis methods of physical optics, geometrical optics, and physical theory of diffraction, which are suitable for RCS analysis of electromagnetically large and complex targets as like naval ships. In addition, a direct scattering center analysis function has been included, which gives relatively simple and intuitive way to discriminate problem areas in design stage when comparing with conventional image-based approaches. In this paper, the theoretical background and the organization of the SYSCOS system are presented. To verify its accuracy and to demonstrate its applicability, numerical analyses for a square plate, a sphere and a cylinder, a weapon system and a virtual naval ship have been carried out, of which results have been compared with analytic solutions and those obtained by the other existing software.

  12. Development of radar cross section analysis system of naval ships

    Directory of Open Access Journals (Sweden)

    Kookhyun Kim

    2012-03-01

    Full Text Available A software system for a complex object scattering analysis, named SYSCOS, has been developed for a systematic radar cross section (RCS analysis and reduction design. The system is based on the high frequency analysis methods of physical optics, geometrical optics, and physical theory of diffraction, which are suitable for RCS analysis of electromagnetically large and complex targets as like naval ships. In addition, a direct scattering center analysis function has been included, which gives relatively simple and intuitive way to discriminate problem areas in design stage when comparing with conventional image-based approaches. In this paper, the theoretical background and the organization of the SYSCOS system are presented. To verify its accuracy and to demonstrate its applicability, numerical analyses for a square plate, a sphere and a cylinder, a weapon system and a virtual naval ship have been carried out, of which results have been compared with analytic solutions and those obtained by the other existing software.

  13. Neutron cross section standards and instrumentation: Annual report

    International Nuclear Information System (INIS)

    1987-01-01

    This annual report from the National Bureau of Standards contains a summary of the results of the Neutron Cross Section Standards and Instrumentation Program. The technical measurements for the past year are given along with the proposed program and budget needs for the next three years. The neutron standards measurements have concentrated on the most important 235 U(n,f) cross section in the thermal to 20 MeV energy range along with the development of neutron detectors required for these measurements. The NBS measurements have made a significant contribution to the improvement in the understanding of this reaction. Measurements were performed with numerous neutron detectors at overlapping energies and at different neutron sources in order to reduce the systematic errors to achieve the required accuracy in this important neutron standard. Significant progress was also made in the development of a detector to utilize the 3 He(n,p) reaction as a standard in the eV to MeV energy region. Improvements in data acquisition systems as well as additional studies of advanced neutron sources were accomplished. Contacts with private industry were maintained and coordination of the neutron standards evaluation was continued. The report also includes biographical listings of the research staff along with copies of a few of our recent publications. 13 figs., 1 tab

  14. Unified description of neutron-, proton- and photon-induced fission cross sections in intermediate energy region

    International Nuclear Information System (INIS)

    Fukahori, Tokio; Iwamoto, Osamu; Chiba, Satoshi

    2003-01-01

    For an accelerator-driven nuclear waste transmutation system, it is very important to estimate sub-criticality of core system for feasibility and design study of the system. The fission cross section in the intermediate energy range has an important role. A program FISCAL has been developed to calculate neutron-, proton- and photon-induced fission cross sections in the energy region from several tens of MeV to 3 GeV. FISCAL adopts the systematics considering experimental data for Ag- 243 Am. It is found that unified description of neutron-, proton- and photon-induced fission cross sections is available. (author)

  15. Experiments on Antiprotons: Cross Sections of Complex Nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Agnew, Jr., Lewis E.; Chamberlain, Owen; Keller, Donald V.; Mermod, Ronald; Rogers, Ernest H.; Steiner, Herbert M.; Wiegand, Clyde

    1957-07-22

    Experiments are described that have been designed to measure separately annihilation and reaction cross sections for antiprotons of approximately 450 MeV on oxygen, copper, silver, and lead. A new and more luminous spectrograph has been built for this experiment. The antiproton cross sections a r e compared with total proton cross sections, and are found to be larger by a factor varying from 1.74 for oxygen to 1.39 for silver. Calculations based on the optical model give a reasonable connection between these cross sections and the 6-p and 6-n cross sections. Finally, the information available on antiproton production cross sections is collected. There are indications that a free nucleon is several times as effective as a bound one for producing antiprotons.

  16. Total cross sections for heavy flavour production at HERA

    CERN Document Server

    Frixione, Stefano; Nason, P; Ridolfi, G; Frixione, S; Mangano, M L; Nason, P; Ridolfi, G

    1995-01-01

    We compute total cross sections for charm and bottom photoproduction at HERA energies, and discuss the relevant theoretical uncertainties. In particular we discuss the problems arising from the small-x region, the uncertainties in the gluon parton density, and the uncertainties in the hadronic component of the cross section. Total electroproduction cross sections, calculated in the Weizs\\"acker-Williams approximation, are also given.

  17. Microscopic cross-section measurements by thermal neutron activation

    International Nuclear Information System (INIS)

    Avila L, J.

    1987-08-01

    Microscopic cross sections measured by thermal neutron activation using RP-0 reactor at the Peruvian Nuclear Energy Institute. The method consists in measuring microscopic cross section ratios through activated samples, requiring being corrected in thermal and epithermal energetic range by Westcott formalism. Furthermore, the comptage ratios measured for each photopeak to its decay fraction should be normalized from interrelation between both processes above, activation microscopic cross sections are obtained

  18. Damage energy and displacement cross sections: survey and sensitivity. [Neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Doran, D.G.; Parkin, D.M.; Robinson, M.T.

    1976-10-01

    Calculations of damage energy and displacement cross sections using the recommendations of a 1972 IAEA Specialists' Meeting are reviewed. The sensitivity of the results to assumptions about electronic energy losses in cascade development and to different choices respecting the nuclear cross sections is indicated. For many metals, relative uncertainties and sensitivities in these areas are sufficiently small that adoption of standard displacement cross sections for neutron irradiations can be recommended.

  19. Differential neutron cross section for free interstitial production in copper

    International Nuclear Information System (INIS)

    Goldstone, J.A.; Parkin, D.M.; Simpson, H.M.

    1979-01-01

    Free interstitials produced by monoenergetic neutrons were monitored by changes in Young's modulus of a vibrating foil specimen. These changes can be related to the number of pinners on dislocations which depends on the number of defects produced. The pinning rate is compared with displacement cross section calculations and agrees with the Norgett--Robinson--Torrens (NRT) model. Electron irradiations on the same sample yield estimates of the free interstitial production cross section to be approx. 1% of the NRT cross section

  20. Damage energy and displacement cross sections: survey and sensitivity

    International Nuclear Information System (INIS)

    Doran, D.G.; Parkin, D.M.; Robinson, M.T.

    1976-10-01

    Calculations of damage energy and displacement cross sections using the recommendations of a 1972 IAEA Specialists' Meeting are reviewed. The sensitivity of the results to assumptions about electronic energy losses in cascade development and to different choices respecting the nuclear cross sections is indicated. For many metals, relative uncertainties and sensitivities in these areas are sufficiently small that adoption of standard displacement cross sections for neutron irradiations can be recommended

  1. Singular gauge fields in inclusive and differential cross sections

    International Nuclear Information System (INIS)

    Ore, F.R. Jr.; Sterman, G.

    1981-01-01

    We study differential and inclusive cross sections for the creation of massless fermions in the presence of a static external non-Abelian field A/sub c1/. We calculate to all orders in A/sub cl/ the correction to the quantum cross section which is suppressed by one power of the energy. Corrections of this type are found to be important even at high energy for sufficiently exclusive cross sections if the classical field has singularities along a line. Their contribution to inclusive cross sections, on the other hand, remains small at high energies

  2. Neutron-capture Cross Sections from Indirect Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Escher, J E; Burke, J T; Dietrich, F S; Ressler, J J; Scielzo, N D; Thompson, I J

    2011-10-18

    Cross sections for compound-nuclear reactions play an important role in models of astrophysical environments and simulations of the nuclear fuel cycle. Providing reliable cross section data remains a formidable task, and direct measurements have to be complemented by theoretical predictions and indirect methods. The surrogate nuclear reactions method provides an indirect approach for determining cross sections for reactions on unstable isotopes, which are difficult or impossible to measure otherwise. Current implementations of the method provide useful cross sections for (n,f) reactions, but need to be improved upon for applications to capture reactions.

  3. Cross sections for atomic processes, vol. 2

    International Nuclear Information System (INIS)

    Takayanagi, Kazuo; Suzuki, Hiroshi; Otani, Shunsuke

    1977-09-01

    This data collection book contains the data on all processes involving hydrogen and helium isotopes, their ions, electrons and photons, collected systematically and comprehensively, and is compiled subsequently to Vol. 1 as one of the works of the data collection study group in the Institute of Plasma Physics, Nagoya University, Japan. The items of the contents will include energy level, multiplicately excited state, radiation process, electron collision, ionic collision, recombination, collision of neutral atoms, colliding process involving molecules, and other processes. However, the first edition this time contains energy level, radiation process, electron collision and ionic collision, and the data on remaining items are now under collection. Though some criticisms have been heard about Vol. 1, the authors consider that such comprehensive collection based on systematic classification is the foundation of making a generalized data bank expected to become necessary in future. Thus the data collection book includes all relevant processes, and records the experimental data and theoretically calculated results in principle without modification by selecting them systematically. This year, investigation on data evaluation is taken up also as one of the tasks of the study group. (Wakatsuki, Y.)

  4. Evaluation of the 56Fe(n,p)56Mn cross sections for ENDF/B-III

    International Nuclear Information System (INIS)

    Dudey, N.D.; Kennerley, R.

    1975-01-01

    The literature examined in this review includes all references in CINDA 71 and its supplements plus some very recent measurements near the reaction threshold. All reference cross sections have been renormalized to ENDF/B-III cross sections and weighted least-squared fitting routines were used to systematize the evaluations

  5. Isospin dependence of capture cross sections: The S36+Pb208 reaction

    Science.gov (United States)

    Yanez, R.; Loveland, W.; Vinodkumar, A. M.; Sprunger, P. H.; Prisbrey, L.; Peterson, D.; Zhu, S.; Kolata, J. J.; Villano, A.; Liang, J. F.

    2010-11-01

    The capture-fission cross section for the S36+Pb208 reaction was measured for seven center-of-mass energies ranging from 147.5 to 210.2 MeV. A comparison of the deduced interaction barriers from “distribution of barriers” measurements and simple 1/Ec.m. plots for 13 well-characterized systems shows the validity of the latter approach for deducing interaction barriers, especially for reaction systems involving radioactive beams where the former measurements are not currently feasible. Application of the 1/Ec.m. plot technique for the S36+Pb208 reaction gives an interaction barrier height of 140.4±1.4 MeV. This value as well as the deduced interaction barriers for all known studies of capture cross sections with radioactive beams are in good agreement with recent predictions of an improved isospin-dependent quantum molecular dynamics model and a modified version of capture cross-section systematics by Swiatecki The deduced barriers for these n-rich systems are lower than one would expect from semiempirical systematics based upon the Bass potential. In addition to the barrier lowering, there is an enhanced subbarrier cross section in these n-rich systems not predicted by the Bass potential systematics. These enhanced subbarrier cross sections may be important in the synthesis of the heaviest nuclei.

  6. Methods and procedures for evaluation of neutron-induced activation cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, M.A.

    1981-09-01

    One cannot expect measurements alone to supply all of the neutron-induced activation cross-section data required by the fission reactor, fusion reactor, and nuclear weapons development communities, given the wide ranges of incident neutron energies, the great variety of possible reaction types leading to activation, and targets both stable and unstable. Therefore, the evaluator must look to nuclear model calculations and systematics to aid in fulfilling these cross-section data needs. This review presents some of the recent developments and improvements in the prediction of neutron activation cross sections, with specific emphasis on the use of empirical and semiempirical methods. Since such systematics require much less nuclear informaion as input and much less computational time than do the multistep Hauser-Feshbach codes, they can often provide certain cross-section data at a sufficient level of accuracy within a minimum amount of time. The cross-section information that these systematics can and cannot provide and those cases in which they can be used most reliably are discussed.

  7. The effect of the decay data on activation cross section

    International Nuclear Information System (INIS)

    Huang Xiaolong

    2002-01-01

    The effect of the decay data on evaluation of activation cross section is investigated. Present work shows that these effects must be considered carefully when activation cross section is evaluated. Sometime they are main reason for causing the discrepancies among the experimental data

  8. determination of neutron-induced activation cross sections using nirr ...

    African Journals Online (AJOL)

    DR. AMINU

    2010-06-01

    Jun 1, 2010 ... Keywords: RNAA, Thermal capture cross section, Resonance integral, k0-factors. INTRODUCTION. A database of activation cross sections for neutron energies (of up to 20MeV) is required for the design of a D-T fusion reactor, neutron dosimetry and neutron shielding in a reactor facility, and for confirming.

  9. Nuclear characteristics of Pu fueled LWR and cross section sensitivities

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Toshikazu [Osaka Univ., Suita (Japan). Faculty of Engineering

    1998-03-01

    The present status of Pu utilization to thermal reactors in Japan, nuclear characteristics and topics and cross section sensitivities for analysis of Pu fueled thermal reactors are described. As topics we will discuss the spatial self-shielding effect on the Doppler reactivity effect and the cross section sensitivities with the JENDL-3.1 and 3.2 libraries. (author)

  10. Temperature dependence of the HNO3 UV absorption cross sections

    Science.gov (United States)

    Burkholder, James B.; Talukdar, Ranajit K.; Ravishankara, A. R.; Solomon, Susan

    1993-01-01

    The temperature dependence of the HNO3 absorption cross sections between 240 and 360 K over the wavelength range 195 to 350 nm has been measured using a diode array spectrometer. Absorption cross sections were determined using both (1) absolute pressure measurements at 298 K and (2) a dual absorption cell arrangement in which the absorption spectrum at various temperatures is measured relative to the room temperature absorption spectrum. The HNO3 absorption spectrum showed a temperature dependence which is weak at short wavelengths but stronger at longer wavelengths which are important for photolysis in the lower stratosphere. The 298 K absorption cross sections were found to be larger than the values currently recommended for atmospheric modeling (DeMore et al., 1992). Our absorption cross section data are critically compared with the previous measurements of both room temperature and temperature-dependent absorption cross sections. Temperature-dependent absorption cross sections of HNO3 are recommended for use in atmospheric modeling. These temperature dependent HNO3 absorption cross sections were used in a two-dimensional dynamical-photochemical model to demonstrate the effects of the revised absorption cross sections on loss rate of HNO3 and the abundance of NO2 in the stratosphere.

  11. Fusion cross sections from measurements of delayed X-rays

    International Nuclear Information System (INIS)

    Pacheco, A.J.; Gregorio, D.E. di; Fernandez Niello, J.O; Elgue, M.

    1988-01-01

    The program XRAY is a FORTRAN 77 computer code for the extraction of fusion cross sections from delayed X-ray measurements. This is accomplished by calculating the theoretical expressions of the time dependence of the evaporation-residue cross sections and taking them as adjustable parameters in a χ 2 minimization procedure. (orig.)

  12. Evaluation of covariance for 238U cross sections

    International Nuclear Information System (INIS)

    Kawano, Toshihiko; Nakamura, Masahiro; Matsuda, Nobuyuki; Kanda, Yukinori

    1995-01-01

    Covariances of 238 U are generated using analytic functions for representation of the cross sections. The covariances of the (n,2n) and (n,3n) reactions are derived with a spline function, while the covariances of the total and the inelastic scattering cross section are estimated with a linearized nuclear model calculation. (author)

  13. Learning of Cross-Sectional Anatomy Using Clay Models

    Science.gov (United States)

    Oh, Chang-Seok; Kim, Ji-Young; Choe, Yeon Hyeon

    2009-01-01

    We incorporated clay modeling into gross anatomy and neuro-anatomy courses to help students understand cross-sectional anatomy. By making clay models, cutting them and comparing cut surfaces to CT and MR images, students learned how cross-sectional two-dimensional images were created from three-dimensional structure of human organs. Most students…

  14. The 10B(n,α)7Li cross section

    International Nuclear Information System (INIS)

    1997-01-01

    The data base relevant to an evaluation of the 10 B(n,α) standard cross sections have been improved through interlaboratory collaboration. Changes in the evaluated 10 B(n,α) cross sections resulted form the measurements made since the ENDF/B-VI evaluation have been estimated. 12 refs, 4 figs

  15. pp production cross sections and the constraint method

    International Nuclear Information System (INIS)

    Anjos, J.C.; Santoro, A.F.S.; Souza, M.H.G.

    1983-01-01

    A method of constructing production cross sections that satisfy the constraints represented by the first few moments is shown to give an excellent account of the data when applied to the high energy pp production cross section ν sub(n) (s) plotted as functions of n. (Author) [pt

  16. An empirical fit to estimated neutron emission cross sections from ...

    Indian Academy of Sciences (India)

    Neutron emission cross section for various elements from 9Be to 209Bi have been calculated using the hybrid model code ALICE-91 for proton induced reactions in the energy range 25 MeV to 105 MeV. An empirical expression relating neutron emission cross section to target mass number and incident proton energy has ...

  17. Graphs of neutron cross section data for fusion reactor development

    International Nuclear Information System (INIS)

    Asami, Tetsuo; Tanaka, Shigeya

    1979-03-01

    Graphs of neutron cross section data relevant to fusion reactor development are presented. Nuclides and reaction types in the present compilation are based on a WRENDA request list from Japan for fusion reactor development. The compilation contains various partial cross sections for 55 nuclides from 6 Li to 237 Np in the energy range up to 20 MeV. (author)

  18. Measurement of neutron-induced activation cross-sections using ...

    Indian Academy of Sciences (India)

    Manish Sharma et al. Table 1. Geometrical details of Co- and Ta-activation detectors used in Gam- ma-2 experiment. Element. 181Ta. 59Co. Cross-sectional area. 2.64 cm2 ... the details of the activated detectors, Au, Bi, and Th as well as the methodology of analysis for the estimation of 'one group cross-section'. Further ...

  19. Is Nurses' Professional Competence Related to Their Personality and Emotional Intelligence? A Cross-Sectional Study

    OpenAIRE

    Abbas Heydari; Hossein Kareshki; Mohammad Reza Armat

    2016-01-01

    Introduction: Nurses' professional competence is a crucial factor in clinical practice. Systematic evaluation of nurses’ competence and its related factors are essential for enhancing the quality of nursing care. This study aimed to assess the nurses’ competence level and its possible relationship with their personality and emotional intelligence. Methods: Using a cross-sectional survey design, three instruments including Nurse Competence Scale, sh...

  20. Low-energy electron impact cross-sections and rate constants of NH2

    Indian Academy of Sciences (India)

    This systematic study reports various electron impact cross-sections, rate constants and transport properties of N H 2 radical in the low-energy limit. The collision study is based on R ... This theoretical study provides a pathway to understand collision dynamics and generates data required in various fields of applied physics.

  1. Evaluation of neutron cross-sections for 242Cm to obtain a complete file

    International Nuclear Information System (INIS)

    Bakhanovich, L.A.; Klepetskij, A.B.; Maslov, V.M.; Porodzinskij, Yu.V.; Sukhovitskij, E.Sh.

    1994-01-01

    Experimental fission, capture, inelastic scattering, (n2n), (n3n) and other cross-sections are scarce or unavailable. As a consequence, theoretical models and parameters systematics have been used extensively in the calculation of these data. Data obtained in this work are compared with previous evaluations. Severe discrepancies were found. (author). 10 refs, 2 figs, 2 tabs

  2. Measurement of the π- proton total cross section from 5 to 15 GeV/c

    International Nuclear Information System (INIS)

    Lelouch, Daniel.

    1979-01-01

    An original method for total cross-section measurement based on a fast microcomputer processing events on line is described. An excellent accuracy is reached by a systematical control of numerous biases. It is shown that the experiment is a first approach to the study of narrow baryonic resonances a multiquark states ('color chemics') [fr

  3. Low-energy electron impact cross-sections and rate constants of

    Indian Academy of Sciences (India)

    Anand Bharadvaja

    2017-07-24

    Jul 24, 2017 ... This systematic study reports various electron impact cross-sections, rate constants and transport properties of NH2 radical in the low-energy limit. The collision study is based on R-matrix formalism ... tion and exchange effects are considered in the inner region. The target and continuum orbitals are repre-.

  4. Photoneutron reaction cross sections from various experiments - analysis and evaluation using physical criteria of data reliability

    Science.gov (United States)

    Varlamov, Vladimir; Ishkhanov, Boris; Orlin, Vadim; Peskov, Nikolai; Stepanov, Mikhail

    2017-09-01

    The majority of photonuclear reaction cross sections important for many fields of science and technology and various data files (EXFOR, RIPL, ENDF, etc.) supported by the IAEA were obtained in experiments using quasimonoenergetic annihilation photons. There are well-known systematic discrepancies between the partial photoneutron reactions (γ, 1n), (γ, 2n), (γ, 3n). For analysis of the data reliability the objective physical criteria were proposed. It was found out that the experimental data for many nuclei are not reliable because of large systematic uncertainties of the neutron multiplicity sorting method used. The experimentally-theoretical method was proposed for evaluating the reaction cross sections data satisfying the reliability criteria. The partial and total reaction cross sections were evaluated for many nuclei. In many cases evaluated data differ noticeably from both the experimental data and the data evaluated before for the IAEA Photonuclear Data Library. Therefore it became evident that the IAEA Library needs to be revised and updated.

  5. Electron collision cross section sets of TMS and TEOS vapours

    Science.gov (United States)

    Kawaguchi, S.; Takahashi, K.; Satoh, K.; Itoh, H.

    2017-05-01

    Reliable and detailed sets of electron collision cross sections for tetramethylsilane [TMS, Si(CH3)4] and tetraethoxysilane [TEOS, Si(OC2H5)4] vapours are proposed. The cross section sets of TMS and TEOS vapours include 16 and 20 kinds of partial ionization cross sections, respectively. Electron transport coefficients, such as electron drift velocity, ionization coefficient, and longitudinal diffusion coefficient, in those vapours are calculated by Monte Carlo simulations using the proposed cross section sets, and the validity of the sets is confirmed by comparing the calculated values of those transport coefficients with measured data. Furthermore, the calculated values of the ionization coefficient in TEOS/O2 mixtures are compared with measured data to confirm the validity of the proposed cross section set.

  6. Classical scattering cross section in sputtering transport theory

    International Nuclear Information System (INIS)

    Zhang Zhulin

    2002-01-01

    For Lindhard scaling interaction potential scattering commonly used in sputtering theory, the authors analyzed the great difference between Sigmund's single power and the double power cross sections calculated. The double power cross sections can give a much better approximation to the Born-Mayer scattering in the low energy region (m∼0.1). In particular, to solve the transport equations by K r -C potential interaction given by Urbassek few years ago, only the double power cross sections (m∼0.1) can yield better approximate results for the number of recoils. Therefore, the Sigmund's single power cross section might be replaced by the double power cross sections in low energy collision cascade theory

  7. Fission cross section measurements of actinides at LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Tovesson, Fredrik [Los Alamos National Laboratory; Laptev, Alexander B [Los Alamos National Laboratory; Hill, Tony S [INL

    2010-01-01

    Fission cross sections of a range of actinides have been measured at the Los Alamos Neutron Science Center (LANSCE) in support of nuclear energy applications. By combining measurement at two LANSCE facilities, Lujan Center and the Weapons Neutron Research center (WNR), differential cross sections can be measured from sub-thermal energies up to 200 MeV. Incident neutron energies are determined using the time-of-flight method, and parallel-plate ionization chambers are used to measure fission cross sections relative to the {sup 235}U standard. Recent measurements include the {sup 233,238}U, {sup 239,242}Pu and {sup 243}Am neutron-induced fission cross sections. In this paper preliminary results for cross section data of {sup 243}Am and {sup 233}U will be presented.

  8. Elastic and inelastic cross section measurements with the ATLAS detector

    CERN Document Server

    Stark, Simon Holm; The ATLAS collaboration

    2017-01-01

    The total pp cross section is a fundamental property of the strong interaction which can not be calculated in perturbative QCD but only described based on phenomenological models. The ATLAS collaboration has measured the total inelastic proton-proton cross section and the diffractive part of the inelastic cross section at 13 TeV in special data sets taken with low beam currents and using forward scintillators. More precise measurements of the total pp cross section and the elastic and inelastic contributions have been extracted from measurements of the differential elastic cross section using the optical theorem. The ATLAS Collaboration has performed this measurement in elastic data collected with high beta* optics at 8 TeV centre-of-mass energy with the ALFA Roman Pot detector.

  9. Applications of the BEam Cross section Analysis Software (BECAS)

    DEFF Research Database (Denmark)

    Blasques, José Pedro Albergaria Amaral; Bitsche, Robert; Fedorov, Vladimir

    2013-01-01

    A newly developed framework is presented for structural design and analysis of long slender beam-like structures, e.g., wind turbine blades. The framework is based on the BEam Cross section Analysis Software – BECAS – a finite element based cross section analysis tool. BECAS is used for the gener......A newly developed framework is presented for structural design and analysis of long slender beam-like structures, e.g., wind turbine blades. The framework is based on the BEam Cross section Analysis Software – BECAS – a finite element based cross section analysis tool. BECAS is used...... for the generation of beam finite element models which correctly account for effects stemming from material anisotropy and inhomogeneity in cross sections of arbitrary geometry. These type of modelling approach allows for an accurate yet computationally inexpensive representation of a general class of three...

  10. Temperature-dependent absorption cross sections for hydrogen peroxide vapor

    Science.gov (United States)

    Nicovich, J. M.; Wine, P. H.

    1988-01-01

    Relative absorption cross sections for hydrogen peroxide vapor were measured over the temperature ranges 285-381 K for lambda = 230 nm-295 nm and 300-381 K for lambda = 193 nm-350 nm. The well established 298 K cross sections at 202.6 and 228.8 nm were used as an absolute calibration. A significant temperature dependence was observed at the important tropospheric photolysis wavelengths lambda over 300 nm. Measured cross sections were extrapolated to lower temperatures, using a simple model which attributes the observed temperature dependence to enhanced absorption by molecules possessing one quantum of O-O stretch vibrational excitation. Upper tropospheric photodissociation rates calculated using the extrapolated cross sections are about 25 percent lower than those calculated using currently recommended 298 K cross sections.

  11. Benchmark of neutron production cross sections with Monte Carlo codes

    Science.gov (United States)

    Tsai, Pi-En; Lai, Bo-Lun; Heilbronn, Lawrence H.; Sheu, Rong-Jiun

    2018-02-01

    Aiming to provide critical information in the fields of heavy ion therapy, radiation shielding in space, and facility design for heavy-ion research accelerators, the physics models in three Monte Carlo simulation codes - PHITS, FLUKA, and MCNP6, were systematically benchmarked with comparisons to fifteen sets of experimental data for neutron production cross sections, which include various combinations of 12C, 20Ne, 40Ar, 84Kr and 132Xe projectiles and natLi, natC, natAl, natCu, and natPb target nuclides at incident energies between 135 MeV/nucleon and 600 MeV/nucleon. For neutron energies above 60% of the specific projectile energy per nucleon, the LAQGMS03.03 in MCNP6, the JQMD/JQMD-2.0 in PHITS, and the RQMD-2.4 in FLUKA all show a better agreement with data in heavy-projectile systems than with light-projectile systems, suggesting that the collective properties of projectile nuclei and nucleon interactions in the nucleus should be considered for light projectiles. For intermediate-energy neutrons whose energies are below the 60% projectile energy per nucleon and above 20 MeV, FLUKA is likely to overestimate the secondary neutron production, while MCNP6 tends towards underestimation. PHITS with JQMD shows a mild tendency for underestimation, but the JQMD-2.0 model with a modified physics description for central collisions generally improves the agreement between data and calculations. For low-energy neutrons (below 20 MeV), which are dominated by the evaporation mechanism, PHITS (which uses GEM linked with JQMD and JQMD-2.0) and FLUKA both tend to overestimate the production cross section, whereas MCNP6 tends to underestimate more systems than to overestimate. For total neutron production cross sections, the trends of the benchmark results over the entire energy range are similar to the trends seen in the dominate energy region. Also, the comparison of GEM coupled with either JQMD or JQMD-2.0 in the PHITS code indicates that the model used to describe the first

  12. Universal trend for heavy-ion total reaction cross sections at energies above the Coulomb barrier

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, O.A.P.; Medeiros, E.L., E-mail: emil@cbpf.b [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil); Morcelle, V. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

    2010-06-15

    Heavy-ion total reaction cross section measurements for more than one thousand one hundred reaction cases covering 61 target nuclei in the range {sup 6}Li-{sup 238}U, and 158 projectile nuclei from {sup 2}H up to {sup 84}Kr (mostly exotic ones) have been analysed in a systematic way by using an empirical, three-parameter formula which is applicable to cases for projectile kinetic energies above the Coulomb barrier. The analysis has shown that the average total nuclear binding energy per nucleon of the interacting nuclei and their radii are the chief quantities which describe the cross section patterns. A great number of cross section data (87%) has been quite satisfactorily reproduced by the proposed formula, therefore total reaction cross section predictions for new, not yet experimentally investigated reaction cases can be obtained within 25 percent (or much less) of uncertainty (author)

  13. Cross-section adjustment techniques for BWR adaptive simulation

    Science.gov (United States)

    Jessee, Matthew Anderson

    Computational capability has been developed to adjust multi-group neutron cross-sections to improve the fidelity of boiling water reactor (BWR) modeling and simulation. The method involves propagating multi-group neutron cross-section uncertainties through BWR computational models to evaluate uncertainties in key core attributes such as core k-effective, nodal power distributions, thermal margins, and in-core detector readings. Uncertainty-based inverse theory methods are then employed to adjust multi-group cross-sections to minimize the disagreement between BWR modeling predictions and measured plant data. For this work, measured plant data were virtually simulated in the form of perturbed 3-D nodal power distributions with discrepancies with predictions of the same order of magnitude as expected from plant data. Using the simulated plant data, multi-group cross-section adjustment reduces the error in core k-effective to less than 0.2% and the RMS error in nodal power to 4% (i.e. the noise level of the in-core instrumentation). To ensure that the adapted BWR model predictions are robust, Tikhonov regularization is utilized to control the magnitude of the cross-section adjustment. In contrast to few-group cross-section adjustment, which was the focus of previous research on BWR adaptive simulation, multigroup cross-section adjustment allows for future fuel cycle design optimization to include the determination of optimal fresh fuel assembly designs using the adjusted multi-group cross-sections. The major focus of this work is to efficiently propagate multi-group neutron cross-section uncertainty through BWR lattice physics calculations. Basic neutron cross-section uncertainties are provided in the form of multi-group cross-section covariance matrices. For energy groups in the resolved resonance energy range, the cross-section uncertainties are computed using an infinitely-dilute approximation of the neutron flux. In order to accurately account for spatial and

  14. Nuclear Data for Reactor Physics: Cross sections and level densities in the actinide region

    Directory of Open Access Journals (Sweden)

    Bernstein L.

    2010-03-01

    Full Text Available Nuclear data in the actinide region are particularly important because they are basis behind all simulations of nuclear reactor core behaviour over both long time scales (fuel depletion and waste production and short time scales (accident scenarios. Nuclear reaction cross sections must be known as precisely as possible so that core reaction rates can be accurately calculated. Although cross section measurements in this region have been widely performed, for certain nuclei, particularly those with short half lives, direct measurements are either very difficult or impossible and thus reactor simulations must rely on theoretical calculations or extrapolations from neighbouring nuclei. The greatest uncertainty in theoretical cross section calculations comes from the lack of knowledge of level densities, for which predicted values can often be incorrect by a factor of two or more. Therefore there is a strong case for a systematic experimental study of level densities in the actinide region for the purpose of a providing a stringent test of theoretical cross section calculations for nuclei where experimental cross section data are available and b for providing better estimations of cross sections for nuclei in which no cross section data are available.

  15. Cross section data for ionization of important cyanides

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, Jaspreet; Antony, Bobby, E-mail: bka.ism@gmail.com

    2015-11-15

    Highlights: • Multi centre spherical complex optical potential formalism used to find the CS. • Effective method (CSP-ic) to derive ionization contribution from inelastic CS. • Result shows excellent accord with previous results and consistent behaviour. • Maiden attempt to find CS for many cyanide molecules. • Strong correlation observed between peak of ionization with target properties. - Abstract: This article presents cross section calculations for interactions of important cyanides with electrons possessing energies beginning from ionization threshold of the target molecule to 5 keV. These data are pursued to meet the ever increasing demand for cross sections by the relevant atomic and molecular community for modelling astrophysical, atmospheric and technological domains. The calculations have been executed using an amalgam of multi centre spherical complex optical potential (MSCOP) formalism and complex scattering potential-ionization contribution (CSP-ic) method. Cross sections are compared with experimental and theoretical data wherever available. Strong correlations are observed for the cross sections which affirms consistent and reliable cross sections. Isomeric effect has been interpreted using variation of cross section with structure and target properties. Our cross sections will be tabulated in atomic collision database for use in modelling various statistical and dynamical quantities.

  16. Neutron standard cross sections in reactor physics - Need and status

    International Nuclear Information System (INIS)

    Carlson, A.D.

    1990-01-01

    The design and improvement of nuclear reactors require detailed neutronics calculations. These calculations depend on comprehensive libraries of evaluated nuclear cross sections. Most of the cross sections that form the data base for these evaluations have been measured relative to neutron cross-section standards. The use of these standards can often simplify the measurement process by eliminating the need for a direct measurement of the neutron fluence. The standards are not known perfectly, however; thus the accuracy of a cross-section measurement is limited by the uncertainty in the standard cross section relative to which it is measured. Improvements in a standard cause all cross sections measured relative to that standard to be improved. This is the reason for the emphasis on improving the neutron cross-section standards. The continual process of measurement and evaluation has led to improvements in the accuracy and range of applicability of the standards. Though these improvements have been substantial, this process must continue in order to obtain the high-quality standards needed by the user community

  17. Parameterized representation of macroscopic cross section for PWR reactor

    International Nuclear Information System (INIS)

    Fiel, João Cláudio Batista; Carvalho da Silva, Fernando; Senra Martinez, Aquilino; Leal, Luiz C.

    2015-01-01

    Highlights: • This work describes a parameterized representation of the homogenized macroscopic cross section for PWR reactor. • Parameterization enables a quick determination of problem-dependent cross-sections to be used in few group calculations. • This work allows generating group cross-section data to perform PWR core calculations without computer code calculations. - Abstract: The purpose of this work is to describe, by means of Chebyshev polynomials, a parameterized representation of the homogenized macroscopic cross section for PWR fuel element as a function of soluble boron concentration, moderator temperature, fuel temperature, moderator density and 235 92 U enrichment. The cross-section data analyzed are fission, scattering, total, transport, absorption and capture. The parameterization enables a quick and easy determination of problem-dependent cross-sections to be used in few group calculations. The methodology presented in this paper will allow generation of group cross-section data from stored polynomials to perform PWR core calculations without the need to generate them based on computer code calculations using standard steps. The results obtained by the proposed methodology when compared with results from the SCALE code calculations show very good agreement

  18. Review of electron impact excitation cross sections for copper atom

    Energy Technology Data Exchange (ETDEWEB)

    Winter, N.W.; Hazi, A.U.

    1982-02-01

    Excitation of atomic copper by electron impact plays an important role in the copper vapor laser and accurate cross sections are needed for understanding and modeling laser performance. During the past seven years, there have been several attempts to normalize the relative elastic and inelastic cross sections measured by Trajmar and coworkers. However, each of these efforts have yielded different cross sections, and the uncertainty in the correct normalization of the data has been a source of confusion and concern for the kinetic modeling efforts. This difficulty has motivated us to review previous work on the electron impact excitation of copper atom and to perform new calculations of the inelastic cross sections using the impact parameter method. In this memorandum we review the previous attempts to normalize the experimental data and provide a critical assessment of the accuracy of the resulting cross sections. We also present new theoretical cross sections for the electron impact excitation of the /sup 2/S ..-->.. /sup 2/P/sup 0/ and /sup 2/S ..-->.. /sup 2/D transitions in copper. When the experimental cross sections are renormalized to the results of the impact parameter calculations, they are a factor of three smaller than those published in the latest paper of Trajmar et. al. At impact energies above 60 eV the excitation cross sections obtained with the impact parameter method agree well with the results of the very recent, unpublished, close-coupling calculations of Henry. This agreement suggests that the present normalization of the experimental cross sections is probably the most reliable one obtained to date.

  19. On the contradiction between the microscopic and integral data for fast neutron absorption cross-section for 238U nuclei

    International Nuclear Information System (INIS)

    Van'kov, A.A.

    1994-01-01

    The contradiction between a measured integral neutron absorption cross-section averaged over a fast reactor spectrum and the corresponding value which was calculated with the use of evaluated microscopic cross-sections and a theoretical neutron spectrum has been investigated. The possible systematic error of a correction factor which takes into account multiple resonance neutron scattering in samples used in the measurement of the absorption cross-section is investigated. It is proposed that this error may be one of the main reason for the contradiction mentioned above which arises in the measurement of the 236 U neutron absorption cross-section. (author). 13 refs, 3 figs

  20. Ionization cross section of partially ionized hydrogen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Baimbetov, F B; Kudyshev, Z A [Department of Physics, al - Farabi Kazakh National University, Almaty (Kazakhstan)], E-mail: Bfb77@kazsu.kz, E-mail: Z.Kudyshev@mail.ru

    2008-05-01

    In present work the electron impact ionization cross section is considered. The electron impact ionization cross section is calculated, based on pseudopotential model of interaction between plasma particles which accounts correlation effects. It is calculated with help of two methods: classical and quantum - mechanical (Born approximation). The ionization cross section is compared with corresponding results of other authors and experimental data. It has been shown that it is very important to take into account an influence of the surrounding during consideration of ionization processes.

  1. Comparison of fission and capture cross sections of minor actinides

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo; Iwamoto, Osamu

    2003-01-01

    The fission and capture cross sections of minor actinides given in JENDL-3.3 are compared with other evaluated data and experimental data. The comparison was made for 32 nuclides of Th-227, 228, 229, 230, 233, 234, Pa-231, 232, 233, U-232, 234, 236, 237, Np-236, 237, 238, Pu-236, 237, 238, 242, 244, Am-241, 242, 242m, 243, Cm-242, 243, 244, 245, 246, 247 and 248. Given in the present report are figures of these cross sections and tables of cross sections at 0.0253 eV and resonance integrals. (author)

  2. Habit, Production, and the Cross-Section of Stock Returns

    OpenAIRE

    Chen, Andrew Y.

    2014-01-01

    Solutions to the equity premium puzzle should inform us about the cross-section of stock returns. An external habit model with heterogeneous firms reproduces numerous stylized facts about both the equity premium and the value premium. The equity premium is large, time-varying, and linked with consumption volatility. The cross-section of expected returns is log-linear in B/M, and the slope matches the data. The explanation for the value premium lies in the interaction between the cross-section...

  3. A method for measuring light ion reaction cross-sections

    International Nuclear Information System (INIS)

    Carlson, R.F.; Ingemarsson, A.; Lantz, M.; Arendse, G.J.; Auce, A.; Cox, A.J.; Foertsch, S.V.; Jacobs, N.M.; Johansson, R.; Nyberg, J.; Peavy, J.; Renberg, P.-U.; Sundberg, O.; Stander, J.A.; Steyn, G.F.; Tibell, G.; Zorro, R.

    2005-01-01

    An experimental procedure for measuring reaction cross-sections of light ions in the energy range 20-50 MeV/nucleon, using a modified attenuation technique, is described. The detection method incorporates a forward detector that simultaneously measures the reaction cross-sections for five different sizes of the solid angle in steps from 99.1% to 99.8% of the total solid angle. The final reaction cross-section values are obtained by extrapolation to the full solid angle

  4. Neutron total scattering cross sections of elemental antimony

    International Nuclear Information System (INIS)

    Smith, A.B.; Guenther, P.T.; Whalen, J.F.

    1982-11-01

    Neutron total cross sections are measured from 0.8 to 4.5 MeV with broad resolutions. Differential-neutron-elastic-scattering cross sections are measured from 1.5 to 4.0 MeV at intervals of 50 to 200 keV and at scattering angles distributed between 20 and 160 degrees. Lumped-level neutron-inelastic-scattering cross sections are measured over the same angular and energy range. The exPerimental results are discussed in terms of an optical-statistical model and are compared with respective values given in ENDF/B-V

  5. LHCb cross-section measurements with heavy flavour jets

    CERN Multimedia

    Michielin, Emanuele

    2017-01-01

    Cross-section measurements of jets originating from the hadronization of beauty ($b$) and charm ($c$) quarks at LHCb give the unique opportunity to probe Parton Distribution Functions (PDFs) at low and large momentum fraction and to test the Standard Model in the forward region. In this poster the production of $t\\bar{t}$ pairs in the forward region, the measurement of the $W+b\\bar{b}$ and $W+c\\bar{c}$ cross-section and the measurement of the $Z\\rightarrow b\\bar{b}$ cross-section are presented.

  6. Actinide neutron-induced fission cross section measurements at LANSCE

    Energy Technology Data Exchange (ETDEWEB)

    Tovesson, Fredrik K [Los Alamos National Laboratory; Laptev, Alexander B [Los Alamos National Laboratory; Hill, Tony S [INL

    2010-01-01

    Fission cross sections of a range of actinides have been measured at the Los Alamos Neutron Science Center (LANSCE) in support of nuclear energy applications in a wide energy range from sub-thermal energies up to 200 MeV. A parallel-plate ionization chamber are used to measure fission cross sections ratios relative to the {sup 235}U standard while incident neutron energies are determined using the time-of-flight method. Recent measurements include the {sup 233,238}U, {sup 239-242}Pu and {sup 243}Am neutron-induced fission cross sections. Obtained data are presented in comparison with ex isting evaluations and previous data.

  7. Fission cross sections in the intermediate energy region

    International Nuclear Information System (INIS)

    Lisowski, P.W.; Gavron, A.; Parker, W.E.; Ullmann, J.L.; Balestrini, S.J.; Carlson, A.D.; Wasson, O.A.; Hill, N.W.

    1991-01-01

    Until recently there has been very little cross section data for neutron-induced fission in the intermediate energy region, primarily because no suitable neutron source has existed. At Los Alamos, the WNR target-4 facility provides a high-intensity source of neutrons nearly ideal for fission measurements extending from a fraction of a MeV to several hundred MeV. This paper summarizes the status of fission cross section data in the intermediate energy range (En > 30 MeV) and presents our fission cross section data for 235 U and 238 U compared to intranuclear cascade and statistical model predictions

  8. Fission cross sections in the intermediate energy region

    Energy Technology Data Exchange (ETDEWEB)

    Lisowski, P.W.; Gavron, A.; Parker, W.E.; Ullmann, J.L.; Balestrini, S.J. (Los Alamos National Lab., NM (USA)); Carlson, A.D.; Wasson, O.A. (National Inst. of Standards and Technology, Gaithersburg, MD (USA)); Hill, N.W. (Oak Ridge National Lab., TN (USA))

    1991-01-01

    Until recently there has been very little cross section data for neutron-induced fission in the intermediate energy region, primarily because no suitable neutron source has existed. At Los Alamos, the WNR target-4 facility provides a high-intensity source of neutrons nearly ideal for fission measurements extending from a fraction of a MeV to several hundred MeV. This paper summarizes the status of fission cross section data in the intermediate energy range (En > 30 MeV) and presents our fission cross section data for {sup 235}U and {sup 238}U compared to intranuclear cascade and statistical model predictions.

  9. Cross sections and transport properties for Na+ in (DXE gas

    Directory of Open Access Journals (Sweden)

    Nikitović Željka D.

    2016-01-01

    Full Text Available In this work we select most probable reactions of alkali metal ion Na+ with dimethoxyethane (DXE molecule. Appropriate gas phase enthalpies of formation for the products were used to calculate scattering cross section as a function of kinetic energy with Denpoh-Nanbu theory. Calculated cross sections were compared with existing experimental results obtained by guided ion beam tandem mass spectrometry. Three body association reactions of ions with DXE is studied and compared to experimental results. Calculated cross sections were used to obtain transport parameters for alkali metal ion in DXE gas. [Projekat Ministarstva nauke Republike Srbije, br. ON 171037 i br. III 410011

  10. Drell-Yan cross section in the jet calculus scheme

    International Nuclear Information System (INIS)

    Tanaka, Hidekazu; Kobayashi, Hirokazu

    2009-01-01

    We calculate factorized cross sections for lepton pair production mediated by a virtual photon in hadron-hadron collisions using the jet calculus scheme, in which a kinematical constraint due to parton radiation is taken into account. This method guarantees a proper phase space boundary for subtraction terms. Some properties of the calculated cross sections are examined. We also discuss matching between the hard scattering cross sections and parton showers at the next-to-leading logarithmic (NLL) order of quantum chromodynamics (QCD). (author)

  11. Parameterized total cross sections for pion production in nuclear collisions

    International Nuclear Information System (INIS)

    Norbury, John W.; Townsend, Lawrence W.

    2007-01-01

    Total inclusive cross sections for neutral and charged pion production in proton-nucleus and nucleus-nucleus reactions have been calculated and compared to experiment. Nucleon-nucleon theoretical cross sections have been scaled up to nuclear collisions using a scaling factor similar to (A P A T ) 2/3 , where A P and A T are the nucleon numbers of the projectile and target nuclei. Variations in the power of this scaling factor have been studied and a good fit to experiment is obtained with a small modification of the power. Theoretical cross sections are written in a form that is very suitable for immediate input into transport codes

  12. Statistical Model Analysis of (n, α Cross Sections for 4.0-6.5 MeV Neutrons

    Directory of Open Access Journals (Sweden)

    Khuukhenkhuu G.

    2016-01-01

    Full Text Available The statistical model based on the Weisskopf-Ewing theory and constant nuclear temperature approximation is used for systematical analysis of the 4.0-6.5 MeV neutron induced (n, α reaction cross sections. The α-clusterization effect was considered in the (n, α cross sections. A certain dependence of the (n, α cross sections on the relative neutron excess parameter of the target nuclei was observed. The systematic regularity of the (n, α cross sections behaviour is useful to estimate the same reaction cross sections for unstable isotopes. The results of our analysis can be used for nuclear astrophysical calculations such as helium burning and possible branching in the s-process.

  13. A genetic algorithm to reduce stream channel cross section data

    Science.gov (United States)

    Berenbrock, C.

    2006-01-01

    A genetic algorithm (GA) was used to reduce cross section data for a hypothetical example consisting of 41 data points and for 10 cross sections on the Kootenai River. The number of data points for the Kootenai River cross sections ranged from about 500 to more than 2,500. The GA was applied to reduce the number of data points to a manageable dataset because most models and other software require fewer than 100 data points for management, manipulation, and analysis. Results indicated that the program successfully reduced the data. Fitness values from the genetic algorithm were lower (better) than those in a previous study that used standard procedures of reducing the cross section data. On average, fitnesses were 29 percent lower, and several were about 50 percent lower. Results also showed that cross sections produced by the genetic algorithm were representative of the original section and that near-optimal results could be obtained in a single run, even for large problems. Other data also can be reduced in a method similar to that for cross section data.

  14. Topological Optimization of Beam Cross Section by Employing Extrusion Constraint

    Science.gov (United States)

    Zuberi, Rehan H.; Zhengxing, Zuo; Kai, Long

    2010-05-01

    Optimal cross-section design of beams plays a characteristic role which signifies the rigidity of the member in bending, shear and torsion load conditions. Practically modern overhead crane girders, railway bridge girders or rail tracks etc. require constant cross-section along the axial direction. Conventional topological optimization modeling procedures in such cases prove inadequate for the reason that these procedures generate non-uniform topologies along the axis of the bending member. To examine optimal topology of those structural bending members which commonly possess constant cross-section along the axis the topology optimization with extrusion constraint is more appropriate. The extrusion constraint method suggests a fresh approach to investigate optimal topologies of beam cross-section under the influence of realistic loading condition across the section at the beginning of design cycle. Presented study is focused upon the influence of various configuration and location of the load and boundary conditions on the topology of the of the beam cross-section which was not possible prior to the materialization of the extrusion or stamping constraint method. Several realistic loads and boundary conditions have been applied on the 3D beam model and optimal cross-section topologies obtained have uniform compliance history and convergent solutions. The lowest compliance criteria have been suggested to choose topologies as furthers shape and size optimization candidates during beam design process.

  15. Total cross sections for positron and electron scattering from pyrimidine

    International Nuclear Information System (INIS)

    Zecca, A; Chiari, L; Trainotti, E; GarcIa, G; Blanco, F; Brunger, M J

    2010-01-01

    In this paper we report original measurements of total cross sections for positron scattering from the important biomolecule pyrimidine. The energy range of these measurements was 0.3-45 eV, while the energy resolution was ∼260 meV. In addition, we report theoretical results, calculated within the independent atom-screened additivity rule (IAM-SCAR) formalism, for the corresponding electron impact total cross sections. In that case the energy range is 1-10 000 eV. Total cross sections are very important input data for codes that seek to simulate charged-particle tracks in matter, as they define the mean-free path between collisions. As the present data and computations are to the best of our knowledge the first total cross sections to be reported for either positron or electron scattering from pyrimidine, they fill an important void in our available knowledge in the literature.

  16. Models for photon-photon total cross-sections

    International Nuclear Information System (INIS)

    Godbole, R.M.; Grau, A.; Pancheri, G.

    1999-01-01

    The paper presents here a brief overview of recent models describing the photon-photon cross-section into hadrons. It shall be showed in detail results from the eikonal minijet model, with and without soft gluon summation

  17. Evaluation of FP cross sections for JENDL-3

    International Nuclear Information System (INIS)

    Kawai, Masayoshi

    1988-01-01

    Evaluation work of cross sections of fission product nuclides for JENDL-3 is in progress as an activity in JNDC FPND sub-working group. Compared to JENDL-2, the number of FP nuclides is extended to 172 by adding As, Se, Br, Sn and Te isotopes and short lived nuclides. Threshold reaction cross sections are also newly contained in the scope of genearal applications. Resonance parameters are evaluated by taking account of recent experimental data up to 1987. The nuclear model parameters are determined for calculating neutron cross sections with the spherical optical model and the statistical theory. The (n,2n), (n,p), (n,α), (n,np) and (n,nα) cross sections are evaluated for all FP nuclides by using the simple evaporation and preequilibrium model. In this paper, evaluation scope and its present status are described. (author)

  18. Generalized reorientation cross section for cylindrically symmetric velocity distributions

    International Nuclear Information System (INIS)

    Generalized reorientation cross sections are derived for the case of atom--molecule collisions where the molecules initially have a velocity distribution cylindrically symmetric about an axis in the laboratory reference frame. This spatial ordering of the velocity can come about, for instance, by exciting molecular electronic states with a light source whose linewidth is much narrower than the Doppler-broadened absorption line. A simple kinetic theory can be set up in terms of state multipoles that are not completely irreducible; the resulting reorientation cross sections are only slightly more complex than the cross sections occurring in a spherically symmetric velocity field. Two approximations are investigated: a McGuire--Kouri m/sub j/-conserving model and a semiclassical model where the orientation of the rotation plane is conserved. The import of the generalized cross sections for several types of experiment and the applicability of the approximate models are discussed

  19. Highlights of top quark cross-section measurements at ATLAS

    Directory of Open Access Journals (Sweden)

    Berta Peter

    2017-01-01

    Full Text Available The highlights of the measurements of top quark production in proton-proton collisions at the Large Hadron Collider with the ATLAS detector are presented. The inclusive measurements of the top-pair production cross section have reached high precision and are compared to the best available theoretical calculations. The differential cross section measurements, including results using boosted top quarks, probe our understanding of top-pair production in the TeV regime. The results are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers. Measurements of the single top quark production cross section are presented in the t-channel and s-channel, and with associated production with a W boson. For the t-channel production, results on the ratio between top quark and antitop quark production cross sections and differential measurements are also included.

  20. Nonelastic-scattering cross sections of elemental nickel

    International Nuclear Information System (INIS)

    Smith, A.B.; Guenther, P.T.; Whalen, J.F.

    1980-06-01

    Neutron total cross sections of elemental nickel were measured from 1.3 to 4.5 MeV, at intervals of approx. 50 keV, with resolutions of 30 to 50 keV and to accuracies of 1 to 2.5%. Neutron differential-elastic-scattering cross sections were measured from 1.45 to 3.8 MeV, at intervals and with resolutions comparable to those of the total cross sections, and to accuracies of 3 to 5%. The nonelastic-scattering cross section is derived from the measured values to accuracies of greater than or equal to 6%. The experimental results are compared with previously reported values as represented by ENDF/B-V, and areas of consistency and discrepancy, noted. The measured results are shown to be in good agreement with the predictions of a model previously reported by the authors. 4 figures, 1 table

  1. Highlights of top quark cross-section measurements at ATLAS

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00349738; The ATLAS collaboration

    2017-01-01

    The highlights of the measurements of top quark production in proton-proton collisions at the Large Hadron Collider with the ATLAS detector are presented. The inclusive measurements of the top-pair production cross section have reached high precision and are compared to the best available theoretical calculations. The differential cross section measurements, including results using boosted top quarks, probe our understanding of top-pair production in the TeV regime. The results are compared to Monte Carlo generators implementing LO and NLO matrix elements matched with parton showers. Measurements of the single top quark production cross section are presented in the t-channel and s-channel, and with associated production with a W boson. For the t-channel production, results on the ratio between top quark and antitop quark production cross sections and differential measurements are also included.

  2. Fully differential cross sections for heavy particle impact ionization

    Energy Technology Data Exchange (ETDEWEB)

    McGovern, M; Walters, H R J [Department of Applied Mathematics and Theoretical Physics, Queen' s University, Belfast BT7 1NN (United Kingdom); Assafrao, D; Mohallem, J R [Laboratorio de Atomos e Moleculas Especiais, Departamento de Fisica, ICEx, Universidade Federal de Minas Gerais, P.O Box 702, 30123-970 Belo Horizonte, MG (Brazil); Whelan, Colm T, E-mail: mmcgovern06@qub.ac.u [Department of Physics, Old Dominion University, Norfolk, VA 23529-0116 (United States)

    2009-11-15

    We describe a procedure for extracting fully differential ionization cross sections from an impact parameter coupled pseudostate treatment of the collision. Some examples from antiproton impact ionization of atomic Hydrogen are given.

  3. Handbook of LHC Higgs Cross Sections: 2. Differential Distributions

    CERN Document Server

    Dittmaier, S; Passarino, G; Tanaka, R; Alekhin, S; Alwall, J; Bagnaschi, E A; Banfi, A; Blumlein, J; Bolognesi, S; Chanon, N; Cheng, T; Cieri, L; Cooper-Sarkar, A M; Cutajar, M; Dawson, S; Davies, G; De Filippis, N; Degrassi, G; Denner, A; D'Enterria, D; Diglio, S; Di Micco, B; Di Nardo, R; Ellis, R K; Farilla, A; Farrington, S; Felcini, M; Ferrera, G; Flechl, M; de Florian, D; Forte, S; Ganjour, S; Garzelli, M V; Gascon-Shotkin, S; Glazov, S; Goria, S; Grazzini, M; Guillet, J -Ph; Hackstein, C; Hamilton, K; Harlander, R; Hauru, M; Heinemeyer, S; Hoche, S; Huston, J; Jackson, C; Jimenez-Delgado, P; Jorgensen, M D; Kado, M; Kallweit, S; Kardos, A; Kauer, N; Kim, H; Kovac, M; Kramer, M; Krauss, F; Kuo, C -M; Lehti, S; Li, Q; Lorenzo, N; Maltoni, F; Mellado, B; Moch, S O; Muck, A; Muhlleitner, M; Nadolsky, P; Nason, P; Neu, C; Nikitenko, A; Oleari, C; Olsen, J; Palmer, S; Paganis, S; Papadopoulos, C G; Petersen, T C; Petriello, F; Petrucci, F; Piacquadio, G; Pilon, E; Potter, C T; Price, J; Puljak, I; Quayle, W; Radescu, V; Rebuzzi, D; Reina, L; Rojo, J; Rosco, D; Salam, G P; Sapronov, A; Schaarschmidt, J; Schonherr, M; Schumacher, M; Siegert, F; Slavich, P; Spira, M; Stewart, I W; Stirling, W J; Stockli, F; Sturm, C; Tackmann, F J; Thorne, R S; Tommasini, D; Torrielli, P; Tramontano, F; Trocsanyi, Z; Ubiali, M; Uccirati, S; Acosta, M Vazquez; Vickey, T; Vicini, A; Waalewijn, W J; Wackeroth, D; Warsinsky, M; Weber, M; Wiesemann, M; Weiglein, G; Yu, J; Zanderighi, G

    2012-01-01

    This Report summarises the results of the second year's activities of the LHC Higgs Cross Section Working Group. The main goal of the working group was to present the state of the art of Higgs Physics at the LHC, integrating all new results that have appeared in the last few years. The first working group report Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables (CERN-2011-002) focuses on predictions (central values and errors) for total Higgs production cross sections and Higgs branching ratios in the Standard Model and its minimal supersymmetric extension, covering also related issues such as Monte Carlo generators, parton distribution functions, and pseudo-observables. This second Report represents the next natural step towards realistic predictions upon providing results on cross sections with benchmark cuts, differential distributions, details of specific decay channels, and further recent developments.

  4. Radiative neutron capture cross sections on 176Lu at DANCE

    Science.gov (United States)

    Roig, O.; Jandel, M.; Méot, V.; Bond, E. M.; Bredeweg, T. A.; Couture, A. J.; Haight, R. C.; Keksis, A. L.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.

    2016-03-01

    The cross section of the neutron capture reaction 176Lu(n ,γ ) has been measured for a wide incident neutron energy range with the Detector for Advanced Neutron Capture Experiments at the Los Alamos Neutron Science Center. The thermal neutron capture cross section was determined to be (1912 ±132 ) b for one of the Lu natural isotopes, 176Lu. The resonance part was measured and compared to the Mughabghab's atlas using the R -matrix code, sammy. At higher neutron energies the measured cross sections are compared to ENDF/B-VII.1, JEFF-3.2, and BRC evaluated nuclear data. The Maxwellian averaged cross sections in a stellar plasma for thermal energies between 5 keV and 100 keV were extracted using these data.

  5. Advantages and disadvantages : longitudinal vs. repeated cross-section surveys

    Science.gov (United States)

    1996-06-20

    The benefits of a longitudinal analysis over a repeated cross-sectional study include increased statistical power and the capability to estimate a greater range of conditional probabilities. With the Puget Sound Transportation Panel (PSTP), and any s...

  6. Electron Swarm Parameters and Electron Collision Cross Sections

    International Nuclear Information System (INIS)

    Nakamura, Yoshiharu

    2012-01-01

    Electron collision cross section data for atoms and molecules and electron swarm data in respective gases are important for quantitative modeling of related plasmas. This fact and wide application of plasmas in various fields boos data collection and evaluation activities worldwide. We have been measuring electron swarm parameters (drift velocity, longitudinal diffusion coefficient, ionization/attachment coefficients, and so on) over a wide E/N range (where E is the electric field and N the gas number density) in a number of gases. We also derived a set of electron collision cross sections for each gas so that the set was consistent with our experimental swarm data. Our speciality in studying molecular target is to measure swarm parameters not only in the pure molecular gas but also in dilute molecular gas-argon gas mixtures, the mix rations of the molecule are 0.5-5.0%. The swarm parameters in pure molecular gas depend primarily on the elastic momentum transfer cross section of the molecule and its vibrational excitation cross sections. Those in the mixtures, on the other hand, depend mainly on the elastic momentum transfer cross section of major argon atom and the vibrational cross sections of minor admixed molecule. Alternative use of swarm parameters in pure molecular gas and those in the mixtures enable us to derive the momentum transfer cross section and vibrational cross sections for the molecule separately. Combination of the Ramsauer-Townsend minimum of argon atom and sharp structures in vibrational cross sections of the molecule frequently gives rise prominent E/N dependences in swarm parameters, which can be used to determine the position and magnitude of resonances in the vibrational excitation cross sections. Detailed accounts of the procedure, including estimated uncertainty in our electron swarm data and also in the resultant set of electron collision cross sections, will be given in the presentation by referring to our recent results. Stress will be

  7. Differential double capture cross sections in p+He collisions

    International Nuclear Information System (INIS)

    Schulz, M.; Brand, J. A.; Vajnai, T.

    2007-01-01

    We have measured differential double capture cross sections for 15 to 150 keV p+He collisions. We also analyzed differential double to single capture ratios, where we find pronounced peak structures. An explanation of these structures probably requires a quantum-mechanical description of elastic scattering between the projectile and the target nucleus. Strong final-state correlations have a large effect on the magnitude of the double capture cross sections

  8. Neutron capture cross section standards for BNL 325, Fourth Edition

    International Nuclear Information System (INIS)

    Holden, N.E.

    1981-01-01

    This report evaluates the experimental data and recommends values for the thermal neutron cross sections and resonance integrals for the neutron capture reactions: 55 Mn(n,γ), 59 Co(n,γ) and 197 Au(n,γ). The failure of lithium and boron as standards due to the natural variation of the absorption cross sections of these elements is discussed. The Westcott convention, which describes the neutron spectrum as a thermal Maxwellian distribution with an epithermal component, is also discussed

  9. MINERvA - neutrino nucleus cross section experiment

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    Recent results from MINERvA, a neutrino cross section experiment at Fermilab, are presented. MINERVA has the goal of providing precision results which will have important impact on oscillation experiments.  Initial data runs for muon neutrino and antineutrino beams of ~3.5 GeV have produced a large number of new results. This seminar will introduce the experiment and describe results for quasielastic, pion production, and inclusive cross sections.

  10. Differential cross sections for neutrino scattering on 12C

    International Nuclear Information System (INIS)

    Kolbe, E.

    1996-01-01

    Differential cross sections for neutrino scattering on 12 C are calculated within the (continuum) random phase approximation model. The charged current (ν e ,e - ) and (ν μ ,μ - ) capture reactions on 12 C are measured by the LSND Collaboration at LAMPF. We investigate and discuss the merits of such studies, especially the information that can be extracted from data for differential neutrino scattering cross sections. copyright 1996 The American Physical Society

  11. Single Boson Production Cross Section Measurements in CMS

    CERN Document Server

    INSPIRE-00571407

    2017-01-01

    Measurements of single boson production cross sections are presented. They are based on proton-proton collision data at 8 and 13 TeV recorded with the CMS detector at the LHC. Inclusive and differential cross sections with respect to various observables are measured in various phase spaces.These measurements are compared to perturbative QCD predictions and generally show good agreement with the prediction.

  12. Electromagnetic-gravitational conversion cross sections in external electromagnetic fields

    International Nuclear Information System (INIS)

    Hoang Ngoc Long; Dang Van Soa; Tuan Tran, A.

    1994-09-01

    The classical processes: the conversion of photons into gravitons in the static electromagnetic fields are considered by using Feynman perturbation techniques. The differential cross sections are presented for the conversion in the electric field of the flat condenser and the magnetic field of the solenoid. A numerical evaluation shows that the cross sections may have the observable value in the present technical scenario. (author). 11 refs

  13. An Ada environment for relativistic cross section calculations

    International Nuclear Information System (INIS)

    Nilsson, E.

    1990-01-01

    We have developed an Ada environment adapted to relativistic cross section calculations. Objects such as four-vectors, γ- matrices and propagators are defined as well as operations between these objects. In this environment matrix elements can be expressed in a compact and readable way as Ada code. Unpolarized cross sections are calculated numerically by explicitly summing and averaging over spins and polarizations. A short presentation of the technique is given

  14. On effective cross section fluctuations in unitary theory

    International Nuclear Information System (INIS)

    Lyuboshits, V.L.; Podgoretskij, M.I.

    1975-01-01

    In the framework of a single-channel theory of overlapping resonances, satisfying the unitarity condition, there were studied the fluctuations of the effective cross sections and the structure of the correlation coefficients for the amplitudes and cross sections. It is shown that at a high overlapping of the resonance levels the characteristic correlation period is determined by an average distance between the levels, but not by the width. The obtained results differ from the conclusions of the statistical Erikson theory

  15. Measurements of the electron and muon inclusive cross-sections

    Indian Academy of Sciences (India)

    We present the measurements of the differential cross-sections for inclusive electron and muon production in proton–proton collisions at a centre-of-mass energy of s = 7 TeV, using ∼ 1.4 pb-1 of data collected by the ATLAS detector at the Large Hadron Collider. The muon cross-section is measured as a function of muon ...

  16. Summary of activation cross section measurements at FNS

    International Nuclear Information System (INIS)

    Ikeda, Y.; Konno, C.; Kasugai, Y.; Kumar, A.

    1996-01-01

    Neutron activation cross sections around 14 MeV for seventeen reactions have been measured at the FNS facility in JAERI in order to provide experimental data meeting the requirement in the radioactive wastes disposal assessment in the D-T fusion reactor. This report summarizes contributing data measured in several phases of experiments to the IAEA-CRP on ''Activation Cross sections for the Generation of Long-Lived radionuclides of Importance in Fusion Reactor Technology''. (author). 18 refs, 1 tab

  17. Ionization of molecules by electron impact: Differential and total cross sections

    International Nuclear Information System (INIS)

    Rezkallah, Z.; Houamer, S.; Dal Cappello, C.; Charpentier, I.; Roy, A.C.

    2011-01-01

    The first Born approximation is applied to calculate differential and total ionization cross sections of a set of small molecules, namely, HF, H 2 O, NH 3 and CH 4 by electron impact. The molecular targets are described by single center molecular orbitals consisting of linear combinations of atomic orbitals (MO-LCAO). First, we have considered electron momentum spectroscopy experiments to check the accuracy of the wave functions. The triply, doubly, singly differential and total cross sections are then evaluated in a systematic way for a variety of kinematics. The results are discussed and compared with experiments.

  18. Proton induced nuclide production cross section by HETC-3STEP/FRG-R

    Energy Technology Data Exchange (ETDEWEB)

    Shigyo, Nobuhiro; Ishibashi, Kenji [Kyushu Univ., Fukuoka (Japan); Yoshizawa, Nobuaki; Takada, Hiroshi

    1998-03-01

    High Energy Transport Code (HETC) based on the intranuclear-cascade-evaporation model is modified to calculate the fragmentation cross section. The exciton model is adopted for improvement of backward nucleon-emission cross section for low-energy nucleon-incident events. The level density parameter depending on the excitation energy is taken in the evaporation process. The fragmentation reaction is incorporated into HETC as a subroutine set by the use of the systematics of the reaction. The modified HETC (HETC-3STEP/FRG-R) reproduces experimental fragment yields to a reasonable degree. (author)

  19. Neutron total cross section measurements of gold and tantalum at the nELBE photoneutron source

    CERN Document Server

    Hannaske, Roland; Beyer, Roland; Junghans, Arnd; Bemmerer, Daniel; Birgersson, Evert; Ferrari, Anna; Grosse, Eckart; Kempe, Mathias; Kögler, Toni; Marta, Michele; Massarczyk, Ralph; Matic, Andrija; Schramm, Georg; Schwengner, Ronald; Wagner, Andreas

    2014-01-01

    Neutron total cross sections of 197 Au and nat Ta have been measured at the nELBE photoneutron source in the energy range from 0.1 - 10 MeV with a statistical uncertainty of up to 2 % and a total systematic uncertainty of 1 %. This facility is optimized for the fast neutron energy range and combines an excellent t ime structure of the neutron pulses (electron bunch width 5 ps) with a short flight path of 7 m. Because of the low instantaneous neutron flux transmission measurements of neutron total cross sections are possible, that exhibit very different beam and back ground conditions than found at other neutron sources.

  20. Measurements of low-energy e+--Ne and e+-Ar total scattering cross sections

    International Nuclear Information System (INIS)

    Charlton, M.; Laricchia, G.; Griffith, T.C.; Wright, G.L.; Heyland, G.R.

    1984-01-01

    Measurements of positron and electron-Ne total scattering cross sections are reported in the energy range 2-50 eV. e + -Ar total cross sections are presented in the energy range 2-20 eV. In both the e + -Ne and e + -Ar cases marked discrepancies are found with other recent measurements and these are discussed along with possible systematic errors which may affect the data. The e - -Ne measurements are found to be in excellent agreement with recent experiments. (author)

  1. Ionization of molecules by electron impact: Differential and total cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Rezkallah, Z. [Laboratoire de Physique Quantique et Systemes Dynamiques, Departement de physique, Faculte des sciences, Universite Ferhat Abbas, Setif 19000 (Algeria); Houamer, S., E-mail: hosalim@yahoo.com [Laboratoire de Physique Quantique et Systemes Dynamiques, Departement de physique, Faculte des sciences, Universite Ferhat Abbas, Setif 19000 (Algeria); Dal Cappello, C. [Laboratoire de Physique Moleculaire et des Collisions, Universite Paul Verlaine-Metz, Institut de Physique, 1 Boulevard Arago, 57078 Metz Cedex 3 (France); Charpentier, I. [Laboratoire de Physique et Mecanique des Materiaux, Universite Paul Verlaine-Metz UMR 7554, ile du Saulcy, 57045 Metz Cedex 1 (France); Roy, A.C. [School of Mathematical Sciences, Ramakrishna Mission Vivekananda University, Belur Math 711202, West Bengal (India)

    2011-12-01

    The first Born approximation is applied to calculate differential and total ionization cross sections of a set of small molecules, namely, HF, H{sub 2}O, NH{sub 3} and CH{sub 4} by electron impact. The molecular targets are described by single center molecular orbitals consisting of linear combinations of atomic orbitals (MO-LCAO). First, we have considered electron momentum spectroscopy experiments to check the accuracy of the wave functions. The triply, doubly, singly differential and total cross sections are then evaluated in a systematic way for a variety of kinematics. The results are discussed and compared with experiments.

  2. Measurement of the inclusive jet cross section with the ATLAS detector at the Large Hadron Collider

    CERN Document Server

    Doglioni, Caterina

    2011-01-01

    This thesis presents the measurement of the inclusive jet cross section using data collected in 2010 by the ATLAS detector, with a particular focus on the reconstruction and calibration techniques used for jets in this measurement and on the estimate of the systematic uncertainty on their energy scale. The inclusive jet cross section measurement is used as input to fits of parton distribution functions. Although the PDF analysis in this thesis is preliminary and its main purpose is to serve as a proof of principle for future studies, improvements in the knowledge of the gluon density are observed thanks to the inclusion of ATLAS data.

  3. Porosity effects in the neutron total cross section of graphite

    International Nuclear Information System (INIS)

    Santisteban, J. R; Dawidowski, J; Petriw, S. N

    2009-01-01

    Graphite has been used in nuclear reactors since the birth of the nuclear industry due to its good performance as a neutron moderator material. Graphite is still an option as moderator for generation IV reactors due to its good mechanical and thermal properties at high operation temperatures. So, there has been renewed interest in a revision of the computer libraries used to describe the neutron cross section of graphite. For sub-thermal neutron energies, polycrystalline graphite shows a larger total cross section (between 4 and 8 barns) than predicted by existing theoretical models (0.2 barns). In order to investigate the origin of this discrepancy we measured the total cross section of graphite samples of three different origins, in the energy range from 0.001 eV to 10 eV. Different experimental arrangements and sample treatments were explored, to identify the effect of various experimental parameters on the total cross section measurement. The experiments showed that the increase in total cross section is due to neutrons scattered around the forward direction. We associate these small-angle scattered neutrons (SANS) to the porous structure of graphite, and formulate a very simple model to compute its contribution to the total cross section of the material. This results in an analytic expression that explicitly depends on the density and mean size of the pores, which can be easily incorporated in nuclear library codes. [es

  4. Muscle quality and age: cross-sectional and longitudinal comparisons.

    Science.gov (United States)

    Metter, E J; Lynch, N; Conwit, R; Lindle, R; Tobin, J; Hurley, B

    1999-05-01

    We addressed whether muscle quality (force per unit muscle mass) changes with age in cross-sectional and longitudinal analyses from three groups from the Baltimore Longitudinal Study of Aging: (1) Isometric arm strength studied cross-sectionally in 617 subjects with muscle mass estimated by cross-sectional area (CSA) from arm circumference and by 24-hour urinary creatinine excretion (CREAT); (2) longitudinal study for 10 to 25 years in 412 men using the same measures as the first group; and (3) isometric knee extensor strength studied cross-sectionally in 675 subjects; muscle mass estimated by CREAT, CSA from thigh circumference, and leg nonosseous fat free mass (FFM) from dual energy x-ray absorptiometry. Muscle quality declined in both arm and leg with age in cross-sectional analyses using CSA and FFM, but not CREAT. No age-associated arm muscle quality declines were observed longitudinally using CREAT or CSA. The relationship between muscle quality and age is dependent on how muscle mass is estimated and on whether subjects are studied cross-sectionally or longitudinally. In addition, CREAT may measure a muscle property not accounted for by CSA or FFM.

  5. Measurement of the elastic cross section for positive pions on carbon at 142 MeV

    International Nuclear Information System (INIS)

    Oyer, A.T.

    1976-12-01

    A measurement of the elastic cross section dsigma/dΩ was made for the reaction π + + 12 C → π + + 12 C with 142 MeV pions at ten angles ranging from 35 to 85 0 in the laboratory. This experiment was done at the Los Alamos Meson Physics Facility. A double focusing magnetic spectrometer observed a cylindrical styrofoam target. The resulting momentum spectra were recorded by an array of nineteen totally depleted surface barrier detectors located at the spectrometer's focal plane. The spectra from the styrofoam were composed of peaks representing proton elastic, carbon elastic, carbon inelastic, and carbon quasi-elastic channels. A function made of Gaussians representing the two body channels and a distribution representing the quasi-elastic channel was fit to the data using a nonlinear least squares algorithm. The ratio of the carbon elastic to proton elastic cross sections was calculated from the areas of the corresponding Gaussians and then multiplied by the proton elastic cross section of Bugg et al eliminating several sources of systematic errors such as beam normalization. The differential cross sections were found to have the usual diffraction structure with a forward peak and a minimum near 55 0 . Finally, the carbon elastic cross sections were compared to similar π - + 12 C cross sections of Binon et al using the optical model

  6. Activation cross section and isomeric cross section ratios for the (n ,2 n ) reaction on 153Eu

    Science.gov (United States)

    Luo, Junhua; Jiang, Li; Li, Suyuan

    2017-10-01

    The 153Eu(n ,2 n ) m1,m2,g152Eu cross section was measured by means of the activation technique at three neutron energies in the range 13-15 MeV. The quasimonoenergetic neutron beam was formed via the 3H(d ,n ) 4He reaction, in the Pd-300 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). The activities induced in the reaction products were measured using high-resolution γ-ray spectroscopy. The cross section of the population of the second high-spin (8-) isomeric state was measured along with the reaction cross section populating both the ground (3-) and the first isomeric state (0-). Cross sections were also evaluated theoretically using the numerical code TALYS-1.8, with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

  7. Models for Pooled Time-Series Cross-Section Data

    Directory of Open Access Journals (Sweden)

    Lawrence E Raffalovich

    2015-07-01

    Full Text Available Several models are available for the analysis of pooled time-series cross-section (TSCS data, defined as “repeated observations on fixed units” (Beck and Katz 1995. In this paper, we run the following models: (1 a completely pooled model, (2 fixed effects models, and (3 multi-level/hierarchical linear models. To illustrate these models, we use a Generalized Least Squares (GLS estimator with cross-section weights and panel-corrected standard errors (with EViews 8 on the cross-national homicide trends data of forty countries from 1950 to 2005, which we source from published research (Messner et al. 2011. We describe and discuss the similarities and differences between the models, and what information each can contribute to help answer substantive research questions. We conclude with a discussion of how the models we present may help to mitigate validity threats inherent in pooled time-series cross-section data analysis.

  8. Measurements of neutron cross sections of radioactive waste nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Katoh, Toshio [Gifu College of Medical Technology, Seki, Gifu (Japan); Harada, Hideo; Nakamura, Shoji; Tanase, Masakazu; Hatsukawa, Yuichi

    1998-01-01

    Accurate nuclear reaction cross sections of radioactive fission products and transuranic elements are required for research on nuclear transmutation methods in nuclear waste management. Important fission products in the nuclear waste management are {sup 137}Cs, {sup 135}Cs, {sup 90}Sr, {sup 99}Tc and {sup 129}I because of their large fission yields and long half-lives. The present authors have measured the neutron capture cross sections and resonance integrals of {sup 137}Cs, {sup 90}Sr and {sup 99}Tc. The purpose of this study is to measure the neutron capture cross sections and resonance integrals of nuclides, {sup 129}I and {sup 135}Cs accurately. Preliminary experiments were performed by using Rikkyo University Reactor and JRR-3 reactor at Japan Atomic Energy Research Institute (JAERI). Then, it was decided to measure the cross section and resonance integral of {sup 135}Cs by using the JRR-3 Reactor because this measurement required a high flux reactor. On the other hand, those of {sup 129}I were measured at the Rikkyo Reactor because the product nuclides, {sup 130}I and {sup 130m}I, have short half-lives and this reactor is suitable for the study of short lived nuclide. In this report, the measurements of the cross section and resonance integral of {sup 135}Cs are described. To obtain reliable values of the cross section and resonance integral of {sup 135}Cs(n, {gamma}){sup 136}Cs reaction, a quadrupole mass spectrometer was used for the mass analysis of nuclide in the sample. A progress report on the cross section of {sup 134}Cs, a neighbour of {sup 135}Cs, is included in this report. A report on {sup 129}I will be presented in the Report on the Joint-Use of Rikkyo University Reactor. (author)

  9. Measurement of the 242Pu neutron capture cross section

    Science.gov (United States)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.; Chyzh, A.; Dance Collaboration

    2015-10-01

    Precision (n,f) and (n, γ) cross sections are important for the network calculations of the radiochemical diagnostic chain for the U.S. DOE's Stockpile Stewardship Program. 242Pu(n, γ) cross section is relevant to the network calculations of Pu and Am. Additionally, new reactor concepts have catalyzed considerable interest in the measurement of improved cross sections for neutron-induced reactions on key actinides. To date, little or no experimental data has been reported on 242Pu(n, γ) for incident neutron energy below 50 keV. A new measurement of the 242Pu(n, γ) reaction was performed with the DANCE together with an improved PPAC for fission-fragment detection at LANSCE during FY14. The relative scale of the 242Pu(n, γ) cross section spans four orders of magnitude for incident neutron energies from thermal to ~ 30 keV. The absolute scale of the 242Pu(n, γ) cross section is set according to the measured 239Pu(n,f) resonance at 7.8 eV; the target was spiked with 239Pu for this measurement. The absolute 242Pu(n, γ) neutron capture cross section is ~ 30% higher than the cross section reported in ENDF for the 2.7 eV resonance. Latest results to be reported. Funded by U.S. DOE Contract No. DE-AC52-07NA27344 (LLNL) and DE-AC52-06NA25396 (LANL). U.S. DOE/NNSA Office of Defense Nuclear Nonproliferation Research and Development. Isotopes (ORNL).

  10. View-CXS neutron and photon cross-sections viewer

    International Nuclear Information System (INIS)

    Subbaiah, K.V.; Sunil Sunny, C.

    2004-01-01

    A graphical user-friendly interface is developed in Visual Basic (VB)-6 to view the variation of neutron and photon interaction cross-sections of different isotopes as a function of energy. VB subroutines developed read the binary data files of cross-sections created in MCNP-ACE (Briesmeister, J.F., 1993. MCNP - a general purpose Monte Carlo N-Particle Transport code. Version 4A. LANL, USA), ANISN-DLC (Engle W.W. Jr., 1967, A User's Manual for ANISN, K-1693; ORNL, 1974. 100 group neutron cross section data based on ENDF/B-III. Oak Ridge National Laboratory, USA) and KENO-AMPX (Petrie, L.M., Landers, N.F., 1984 KENO-Va- An Improved Monte Carlo Criticality Program with Super Grouping. RSICC-CCC-548, USA) formats using LAHEY-77 Fortran Compiler. The information on isotopes present in each library will be displayed with the help of database files prepared using Micro-Soft ACESS. The cross-section data can be viewed in different presentation styles namely, line graphs, bar graphs, histograms etc., with different color and symbol options. The cross-section plots generated can be saved as Bit-Map file to embed in any other text files. This software enables inter comparison of cross-sections from different type of libraries for isotopes as well as mixtures. Provision is made to view the cross-sections for nuclear reactions such as (n,γ), (n,f), (n,α), etc. The software can be obtained from Radiation Safety Information and Computational Centre (RSICC), ORNL, USA with the code package identification number PSR-514. The software package needs a hard disk space of about 80 MB when installed and works in WINDOWS-95/98/2000 operating systems

  11. CrossFit Overview: Systematic Review and Meta-analysis.

    Science.gov (United States)

    Claudino, João Gustavo; Gabbett, Tim J; Bourgeois, Frank; Souza, Helton de Sá; Miranda, Rafael Chagas; Mezêncio, Bruno; Soncin, Rafael; Cardoso Filho, Carlos Alberto; Bottaro, Martim; Hernandez, Arnaldo Jose; Amadio, Alberto Carlos; Serrão, Julio Cerca

    2018-02-26

    CrossFit is recognized as one of the fastest growing high-intensity functional training modes in the world. However, scientific data regarding the practice of CrossFit is sparse. Therefore, the objective of this study is to analyze the findings of scientific literature related to CrossFit via systematic review and meta-analysis. Systematic searches of the PubMed, Web of Science, Scopus, Bireme/MedLine, and SciELO online databases were conducted for articles reporting the effects of CrossFit training. The systematic review followed the PRISMA guidelines. The Oxford Levels of Evidence was used for all included articles, and only studies that investigated the effects of CrossFit as a training program were included in the meta-analysis. For the meta-analysis, effect sizes (ESs) with 95% confidence interval (CI) were calculated and heterogeneity was assessed using a random-effects model. Thirty-one articles were included in the systematic review and four were included in the meta-analysis. However, only two studies had a high level of evidence at low risk of bias. Scientific literature related to CrossFit has reported on body composition, psycho-physiological parameters, musculoskeletal injury risk, life and health aspects, and psycho-social behavior. In the meta-analysis, significant results were not found for any variables. The current scientific literature related to CrossFit has few studies with high level of evidence at low risk of bias. However, preliminary data has suggested that CrossFit practice is associated with higher levels of sense of community, satisfaction, and motivation.

  12. Hartree-Fock calculation of the differential photoionization cross sections of small Li clusters.

    Science.gov (United States)

    Galitskiy, S A; Artemyev, A N; Jänkälä, K; Lagutin, B M; Demekhin, Ph V

    2015-01-21

    Cross sections and angular distribution parameters for the single-photon ionization of all electron orbitals of Li2-8 are systematically computed in a broad interval of the photoelectron kinetic energies for the energetically most stable geometry of each cluster. Calculations of the partial photoelectron continuum waves in clusters are carried out by the single center method within the Hartree-Fock approximation. We study photoionization cross sections per one electron and analyze in some details general trends in the photoionization of inner and outer shells with respect to the size and geometry of a cluster. The present differential cross sections computed for Li2 are in a good agreement with the available theoretical data, whereas those computed for Li3-8 clusters can be considered as theoretical predictions.

  13. Total fragmentation cross section of 158A GeV lead projectiles in Cu target

    International Nuclear Information System (INIS)

    Mukhtar Ahmed Rana; Shahid Manzoor

    2008-01-01

    Total fragmentation cross section for the reaction 158A Pb ions + Cu target is measured using the most sensitive track detector CR-39. Measured values are compared with calculations. Exposures of target-detector stack with 158A Pb projectiles are made at CERN-SPS beam facility. Results of calibration of CR-39 detector in a charge region (63≤Z≤83) are also reported, which can be used for high energy particle identification using CR-39 and in determination of partial charge changing cross sections. The charge resolution σ Z achieved by this technique is about 0.2e. A systematic dependence of total fragmentation cross section on target properties is revealed and the corresponding results are presented. (authors)

  14. Total Fragmentation Cross Section of 158A GeV Lead Projectiles in Cu Target

    International Nuclear Information System (INIS)

    Rana, Mukhtar Ahmed

    2008-01-01

    Total fragmentation cross section for the reaction 158 A Pb ions + Cu target is measured using the most sensitive track detector CR-39. Measured values are compared with calculations. Exposures of target-detector stack with 158A Pb projectiles are made at CERN-SPS beam facility. Results of calibration of CR-39 detector in a charge region (63 ≤ Z ≤ 83) are also reported, which can be used for high energy particle identification using CR-39 and in determination of partial charge changing cross sections. The charge resolution σ z achieved by this technique is about 0.2e. A systematic dependence of total fragmentation cross section on target properties is revealed and the corresponding results are presented. (nuclear physics)

  15. Determination of alpha_s using jet cross section parameterizations at hadron colliders

    CERN Document Server

    Stenzel, H

    2001-01-01

    Precise measurements of the single inclusive jet cross section have been performed by the TEVATRON experiments and will be provided by the LHC experiments extending to larger values of transverse energy. Theoretical predictions of this observable at NLO in perturbative QCD depend both on the PDF parameterization set and on the value of the strong coupling constant alpha_s. In this paper the dependence of the jet cross section on alpha_s is investigated. A method is presented to extract alpha_s(E_T) from a cross section measurement based on a parameterization of the alpha_s dependence. Systematic uncertainties and the E_T-range of applicability are discussed. A comparative study is performed between the case of ppbar at sqrt{s}=1.8 TeV (TEVATRON) and pp scattering at sqrt{s}=14 TeV (LHC).

  16. Energy dependence of fusion evaporation-residue cross sections in the 28Si+12C reaction

    International Nuclear Information System (INIS)

    Vineyard, M.F.; Mateja, J.F.; Beck, C.; Atencio, S.E.; Dennis, L.C.; Frawley, A.D.; Henderson, D.J.; Janssens, R.V.F.; Kemper, K.W.; Kovar, D.G.; Maguire, C.F.; Padalino, S.J.; Prosser, F.W.; Stephans, G.S.F.; Tiede, M.A.; Wilkins, B.D.; Zingarelli, R.A.

    1993-01-01

    Fusion evaporation-residue cross sections for the 28 Si+ 12 C reaction have been measured in the energy range 18≤E c.m. ≤136 MeV using time-of-flight techniques. Velocity distributions of mass-identified reaction products were used to identify evaporation residues and to determine the complete-fusion cross sections at high energies. The data are in agreement with previously established systematics which indicate an entrance-channel mass-asymmetry dependence of the incomplete-fusion evaporation-residue process. The complete-fusion evaporation-residue cross sections and the deduced critical angular momenta are compared with earlier measurements and the predictions of existing models

  17. Cross-sectional vestibular nerve analysis in vestibular neuritis.

    Science.gov (United States)

    Fundakowski, Christopher E; Anderson, Joshua; Angeli, Simon

    2012-07-01

    We examined the association between the size and cross-sectional area of the superior vestibular nerve as measured on constructive interference in steady-state (CISS) parasagittal magnetic resonance imaging (MRI) and the vestibular nerve function as measured by electronystagmography. The retrospective observational cohort study took place at an academic tertiary referral center. Twenty-six patients who met established clinical and electronystagmographic criteria for vestibular neuritis and who underwent parasagittal CISS MRI were identified. Two blinded investigators measured vestibular nerve height and width bilaterally at the level of the fundus of the internal auditory canal and calculated the cross-sectional nerve areas. The inter-rater reliability and agreement were analyzed. Symptom duration, age, and gender were also examined. A statistically significant decrease was observed in both vestibular nerve cross-sectional area and height as compared to the contralateral vestibular nerve. A non-statistically significant trend was observed for a relative decreased cross-sectional nerve area with increased age, as well as a decrease in nerve area with an increase in symptom duration. Decreases in both vestibular nerve cross-sectional area and height are observed in patients with unilateral vestibular neuritis as measured on parasagittal CISS MRI.

  18. JENDL-2 fission-product cross section data file

    International Nuclear Information System (INIS)

    1985-01-01

    The evaluation of the new set of the fission-product cross section data for JENDL-2 was started in 1979 and completed in October 1984. This data file contains 100 nuclides (Z = 36 - 65) which make contributions of about 195 % of the total fission yield from Pu-239 fission, and 99.6 % of the total neutron capture by fission products in a typical fast breeder reactors. Cross section data in the neutron energy range of 10 -5 eV - 20 MeV for the following reactions are stored; total, capture, elastic and inelastic scattering. Recent resonance and KeV capture data and the integral test results on JENDL-1 library were reflected on the new evaluation. The evaluated 2200 m/s capture cross sections and resonance integrals are listed in a table. The values of 30 KeV capture cross sections multiplied by Pu-239 cumulative fission yield for long-lived fission products are also listed in decreasing order, representing the rough order of importance of nuclides for long burnup in a large fast breeder reactor. The integral tests and limited adjustment of cross sections based on integral data are planned as well as the extension of the number of nuclides. (Aoki, K.)

  19. Modelling interaction cross sections for intermediate and low energy ions

    International Nuclear Information System (INIS)

    Toburen, L.H.; Shinpaugh, J.L.; Justiniano, E.L.B.

    2002-01-01

    When charged particles slow in tissue they undergo electron capture and loss processes than can have profound effects on subsequent interaction cross sections. Although a large amount of data exists for the interaction of bare charged particles with atoms and molecules, few experiments have been reported for these 'dressed' particles. Projectile electrons contribute to an impact-parameter-dependent screening of the projectile charge that precludes straightforward scaling of energy loss cross sections from those of bare charged particles. The objective of this work is to develop an analytical model for the energy-loss-dependent effects of screening on differential ionisation cross sections that can be used in track structure calculations for high LET ions. As a first step a model of differential ionisation cross sections for bare ions has been combined with a simple screening model to explore cross sections for intermediate and low energy dressed ions in collisions with atomic and molecular gas targets. The model is described briefly and preliminary results compared to measured electron energy spectra. (author)

  20. 242Pu absolute neutron-capture cross section measurement

    Science.gov (United States)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Chyzh, A.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.

    2017-09-01

    The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. During target fabrication, a small amount of 239Pu was added to the active target so that the absolute scale of the 242Pu(n,γ) cross section could be set according to the known 239Pu(n,f) resonance at En,R = 7.83 eV. The relative scale of the 242Pu(n,γ) cross section covers four orders of magnitude for incident neutron energies from thermal to ≈ 40 keV. The cross section reported in ENDF/B-VII.1 for the 242Pu(n,γ) En,R = 2.68 eV resonance was found to be 2.4% lower than the new absolute 242Pu(n,γ) cross section.

  1. 242Pu absolute neutron-capture cross section measurement

    Directory of Open Access Journals (Sweden)

    Buckner M.Q.

    2017-01-01

    Full Text Available The absolute neutron-capture cross section of 242Pu was measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. During target fabrication, a small amount of 239Pu was added to the active target so that the absolute scale of the 242Pu(n,γ cross section could be set according to the known 239Pu(n,f resonance at En,R = 7.83 eV. The relative scale of the 242Pu(n,γ cross section covers four orders of magnitude for incident neutron energies from thermal to ≈ 40 keV. The cross section reported in ENDF/B-VII.1 for the 242Pu(n,γ En,R = 2.68 eV resonance was found to be 2.4% lower than the new absolute 242Pu(n,γ cross section.

  2. Progress on FP13 Total Cross Section Measurements Capability

    Energy Technology Data Exchange (ETDEWEB)

    Ullmann, John Leonard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Couture, Aaron Joseph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Koehler, Paul E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mocko, Michal [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mosby, Shea Morgan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wender, Stephen Arthur [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-26

    An accurate knowledge of the neutron capture cross section is important for many applications. Experimental measurements are important since theoretical calculations of capture have been notoriously difficult, with the ratio of measured to calculated cross sections often a factor of 2 or more in the 10 keV to 1 MeV region. However, a direct measurement of capture cannot be made on many interesting radioactive nuclides because of their short half-life or backgrounds caused by their nuclear decay. On the other hand, neutron transmission measurements of the total cross section are feasible for a wide range of radioactive nuclides since the detectors are far from the sample, and often are less sensitive to decay radiation. The parameters extracted from a total cross section measurement, which include the average resonance spacing, the neutron strength function, and the average total radiation width, (Γγ), provide tight constraints on the calculation of the capture cross section, and when applied produce much more accurate results. These measurements can be made using the intense epithermal neutron flux at the Lujan Center on relatively small quantities of target material. It was the purpose of this project to investigate and develop the capability to make these measurements. A great deal of progress was made towards establishing this capability during 2016, including setting up the flight path and obtaining preliminary results, but more work remains to be done.

  3. Penning ionization cross sections of excited rare gas atoms

    International Nuclear Information System (INIS)

    Ukai, Masatoshi; Hatano, Yoshihiko.

    1988-01-01

    Electronic energy transfer processes involving excited rare gas atoms play one of the most important roles in ionized gas phenomena. Penning ionization is one of the well known electronic energy transfer processes and has been studied extensively both experimentally and theoretically. The present paper reports the deexcitation (Penning ionization) cross sections of metastable state helium He(2 3 S) and radiative He(2 1 P) atoms in collision with atoms and molecules, which have recently been obtained by the authors' group by using a pulse radiolysis method. Investigation is made of the selected deexcitation cross sections of He(2 3 S) by atoms and molecules in the thermal collisional energy region. Results indicate that the cross sections are strongly dependent on the target molecule. The deexcitation probability of He(2 3 S) per collision increases with the excess electronic energy of He(2 3 S) above the ionization potential of the target atom or molecule. Another investigation, made on the deexcitation of He(2 1 P), suggests that the deexcitation cross section for He(2 1 P) by Ar is determined mainly by the Penning ionization cross section due to a dipole-dipole interaction. Penning ionization due to the dipole-dipole interaction is also important for deexcitation of He(2 1 P) by the target molecules examined. (N.K.)

  4. Cross-sections for inelastic collisions of fast charged particles with atoms and molecules

    International Nuclear Information System (INIS)

    Inokuti, M.

    1987-01-01

    Despite the long history of research, the current experimental data of the cross-sections, required for solving problems of radiological physics and dosimetry, are far from being complete or even satisfactory for tentative applications. Calculations are, in general, difficult and only in exceptional situations lead to reliable results. Thus, one practical approach to the cross-section determination is to test experimental data with general criteria. This is possible because cross-sections for various processes are related among themselves and with many other properties of atoms and molecules. For example, the Bethe theory indicates a close connection between photoabsorption and energy absorption by glancing collisions and puts many other useful constraints on the cross-section data. Development and use of these data constraints, first advanced by Platzman, can now be demonstrated in many examples. More recent studies concern the determination of the analytic expression most suitable for fitting the data on the oscillator strength distribution or the energy distribution of secondary electrons from ionizing collisions of charged particles. There are three areas to which major efforts should be directed: (1) Methods of absolute cross-section measurements, both for electron and ionic collisions, must be thoroughly reviewed so that sources of systematic errors may be identified and corrected. (2) Efforts should be devoted to the understanding of the data systematics, viz. the trends of cross-sections for a series of molecules. This is especially important because the variety of molecules relevant to radiological physics and radiation biology is so enormous that even the data presentation for each molecule will be impractical. (3) Electron and ionic collisions with molecules in condensed phases will be an important topic of study for years to come. Initial reports on efforts in this direction are encouraging. 49 refs

  5. Nucleus-neutron interactions in the region of lead and actinides from measurements of total cross sections, elastic scattering cross sections and inelastic scattering cross sections

    International Nuclear Information System (INIS)

    Lachkar, J.; Haouat, G.; Lagrange, C.; Cates, M.; Patin, Y.; Sigaud, J.; Jary, J.; Ferguson, S.; Shamu, R.E.

    1978-01-01

    In order to study the neutron-nucleus interaction for nuclei in the mass region from A=248 to A=240, neutron data have been taken which include total cross sections for 208 Pb, 232 Th, 235 U, 238 U and 239 Pu between 1.4 and 14 MeV, elastic scattering cross sections for 208 Pb at 2.5 and 3.4 MeV, and elastic and inelastic scattering cross sections for 208 Pb at 7.5 - 9.5 - 11.5 and 13.5 MeV, for 232 Th and 238 U at 0.7 - 2.5 and 3.4 MeV and for 235 U and 239 Pu at 0.7 and 3.4 MeV. These data have been analysed using the DWBA formalism for 208 Pb and the coupled-channels formalism for the actinides. Optical potential parameters and nuclear deformation parameters have been deduced from these analyses. (author) [fr

  6. Triply differential cross section and polarization correlations in electron bremsstrahlung emission

    International Nuclear Information System (INIS)

    Shaffer, C.D.; Tong, X.; Pratt, R.H.

    1996-01-01

    We report results from a reformulation of the relativistic bremsstrahlung code of Tseng and Pratt. This permits calculation of the triply differential cross section d 3 σ of bremsstrahlung (electron-photon coincidence measurements) in electron scattering on neutral atoms and ions. The cross section d 3 σ is viewed as a more sensitive test of the theory, and predictions are needed for comparison with the more systematic and accurate experiments which are now being undertaken. The reformulation represents an extension of the previous code (which only calculated the doubly differential cross section), again utilizing partial-wave and multipole expansions in a screened potential within the independent particle approximation, but differently organizing their summation. The best previous predictions for the triply differential cross sections are due to Elwert and Haug, under assumptions less restrictive than Born approximation yet valid for high-Z elements only at very high incident electron energy. While we confirm differences from the Elwert-Haug results, we do not see a systematic improvement in the agreement with the limited previous experimental data, and further experiments are awaited with interest. copyright 1996 The American Physical Society

  7. (237)Np(n,f) Cross Section: New Data and Present Status

    CERN Document Server

    Paradela, C; Carrapico, C; Eleftheriadis, C; Leeb, H; Calvino, F; Herrera-Martinez, A; Savvidis, I; Vlachoudis, V; Haas, B; Vannini, G; Le Naour, C; Gramegna, F; Wiescher, M; Pigni, M T; Audouin, L; Mengoni, A; Quesada, J; Becvar, F; Plag, R; Cennini, P; Mosconi, M; Duran, I; Rauscher, T; Couture, A; Capote, R; Sarchiapone, L; Vlastou, R; Domingo-Pardo, C; Dillmann, I; Pavlopoulos, P; Karamanis, D; Krticka, M; Jericha, E; Ferrari, A; Martinez, T; Trubert, D; Oberhummer, H; Karadimos, D; Plompen, A; Isaev, S; Terlizzi, R; Kaeppeler, F; Cortes, G; Cox, J; Voss, F; Pretel, C; Colonna, N; Berthoumieux, E; Vaz, P; Heil, M; Lopes, I; Lampoudis, C; Walter, S; Calviani, M; Gonzalez-Romero, E; Embid-Segura, M; Stephan, C; Igashira, M; Papachristodoulou, C; Aerts, G; Tavora, L; Berthier, B; Rudolf, G; Andrzejewski, J; Villamarin, D; Ferreira-Marques, R; Tain, J L; O'Brien, S; Gunsing, F; Reifarth, R; Perrot, L; Lindote, A; Neves, F; Poch, A; Kerveno, M; Rubbia, C; Koehler, P; Dahlfors, M; Wisshak, K; Salgado, J; Dridi, W; Ventura, A; Andriamonje, S; Assimakopoulos, P; Santos, C; Ferrant, L; Lozano, M; Patronis, N; Chiaveri, E; Guerrero, C; Kadi, Y; Vicente, M C; Praena, J; Baumann, P; Oshima, M; Rullhusen, P; Furman, W; David, S; Marrone, S; Tassan-Got, L; Cano-Ott, D; Pavlix, A; Alvarez-Velarde, F; Massimi, C; Mastinu, P; Pancin, J; Papadopoulos, C; Tagliente, G; Haight, R; Chepel, V; Kossionides, E; Badurek, G; Marganiec, J; Lukic, S; Tarrio, D; Alvarez, H

    2011-01-01

    In this document, we present the final result obtained at the n_TOF experiment; for the neutron-induced fission cross section of the (237)Np, from the fission threshold up to 1 GeV. The method applied to get tins result is briefly discussed. n_TOF data are compared to the last experimental measurements using other TOF facilities or the surrogate method, reported experiments performed with monoenergetic sources and the FISCAL systematic, including a discussion about the existing discrepancies.

  8. Evaluation of fission product neutron cross sections for JENDL

    International Nuclear Information System (INIS)

    1984-01-01

    The recent activities on the evaluation of fission product (FP) neutron cross sections for JENDL (Japanese Evaluated Nuclear Data Library) are presented briefly. The integral test of JENDL-1 FP cross section file was performed using the CFRMF sample activation data and the STEK sample reactivity data, and the ratio of experiment to calculation was nearly constant for all the samples in the STEK measurement. Therefore, a tentative analysis was performed by applying the correction to the calculated scattering reactivity component. Better agreement with the experiment was obtained after applying this correction in most cases. The evaluation work on the JENDL-2 FP neutron cross sections is now in progress. The improvement of the data evaluation is presented in an itemized form. The JENDL-2 FP file will contain the evaluated data for 100 nuclides from Kr to Tb. The improvement and the future scope of the integral test for JENDL-2 FP data are summarized. (Asami, T.)

  9. Proton-air and proton-proton cross sections

    Directory of Open Access Journals (Sweden)

    Ulrich Ralf

    2013-06-01

    Full Text Available Different attempts to measure hadronic cross sections with cosmic ray data are reviewed. The major results are compared to each other and the differences in the corresponding analyses are discussed. Besides some important differences, it is crucial to see that all analyses are based on the same fundamental relation of longitudinal air shower development to the observed fluctuation of experimental observables. Furthermore, the relation of the measured proton-air to the more fundamental proton-proton cross section is discussed. The current global picture combines hadronic proton-proton cross section data from accelerator and cosmic ray measurements and indicates a good consistency with predictions of models up to the highest energies.

  10. Cross-Sectional Transport Imaging in a Multijunction Solar Cell

    Energy Technology Data Exchange (ETDEWEB)

    Haegel, Nancy M.; Ke, Chi-Wen; Taha, Hesham; Guthrey, Harvey; Fetzer, C. M.; King, Richard

    2015-06-14

    Combining highly localized electron-beam excitation at a point with the spatial resolution capability of optical near-field imaging, we have imaged carrier transport in a cross-sectioned multijunction (GaInP/GaInAs/Ge) solar cell. We image energy transport associated with carrier diffusion throughout the full width of the middle (GaInAs) cell and luminescent coupling from point excitation in the top cell GaInP to the middle cell. Supporting cathodoluminescence and near-field photoluminescence measurements demonstrate excitation-dependent Fermi level splitting effects that influence cross-sectioned spectroscopy results as well as transport limitations on the spatial resolution of cross-sectional measurements.

  11. Reaction cross section calculation of some alkaline earth elements

    Science.gov (United States)

    Tel, Eyyup; Kavun, Yusuf; Sarpün, Ismail Hakki

    2017-09-01

    Reaction cross section knowledge is crucial to application nuclear physics such as medical imaging, radiation shielding and material evaluations. Nuclear reaction codes can be used if the experimental data are unavailable or are improbably to be produced because of the experimental trouble. In this study, there action cross sections of some target alkaline earth elements have been calculated by using pre-equilibrium and equilibrium nuclear reaction models for nucleon induced reactions. While these calculations, the Hybrid Model, the Geometry Dependent Hybrid Model, the Full Exciton Model, the Cascade Exciton Model for pre-equilibrium reactions and the Weisskopf-Ewing Model for equilibrium reactions have been used. The calculated cross sections have been discussed and compared with the experimental data taken from Experimental Nuclear Reaction Data library.

  12. Preparation of higher-actinide burnup and cross section samples

    International Nuclear Information System (INIS)

    Adair, H.L.; Kobisk, E.H.; Quinby, T.C.; Thomas, D.K.; Dailey, J.M.

    1981-01-01

    A joint research program involving the United States and the United Kingdom was instigated about four years ago for the purpose of studying burnup of higher actinides using in-core irradiation in the fast reactor at Dounreay, Scotland. Simultaneously, determination of cross sections of a wide variety of higher actinide isotopes was proposed. Coincidental neutron flux and energy spectral measurements were to be made using vanadium encapsulated dosimetry materials in the immediate region of the burnup and cross section samples. The higher actinide samples chosen for the burnup study were 241 Am and 244 Cm in the forms of Am 2 O 3 , Cm 2 O 3 , and Am 6 Cm(RE) 7 O 21 , where (RE) represents a mixture of lanthanide sesquioxides. It is the purpose of this paper to describe technology development and its application in the preparation of the fuel specimens and the cross section specimens that are being used in this cooperative program

  13. High Energy Measurement of the Deuteron Photodisintegration Differential Cross Section

    Energy Technology Data Exchange (ETDEWEB)

    Schulte, Elaine [Univ. of Illinois, Urbana-Champaign, IL (United States)

    2002-05-01

    New measurements of the high energy deuteron photodisintegration differential cross section were made at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia. Two experiments were performed. Experiment E96-003 was performed in experimental Hall C. The measurements were designed to extend the highest energy differential cross section values to 5.5 GeV incident photon energy at forward angles. This builds upon previous high energy measurements in which scaling consistent with the pQCD constituent counting rules was observed at 90 degrees and 70 degrees in the center of mass. From the new measurements, a threshold for the onset of constituent counting rule scaling seems present at transverse momentum approximately 1.3 GeV/c. The second experiment, E99-008, was performed in experimental Hall A. The measurements were designed to explore the angular distribution of the differential cross section at constant energy. The measurements were made symmetric about 90 degrees

  14. Fast-neutron total and scattering cross sections of niobium

    International Nuclear Information System (INIS)

    Smith, A.B.; Guenther, P.T.; Whalen, J.F.

    1982-07-01

    Neutron total cross sections of niobium were measured from approx. = 0.7 to 4.5 MeV at intervals of less than or equal to 50 keV with broad resolution. Differential-elastic-scattering cross sections were measured from approx. = 1.5 to 4.0 MeV at intervals of 0.1 to 0.2 MeV and at 10 to 20 scattering angles distributed between approx. = 20 and 160 degrees. Inelastically-scattered neutrons, corresponding to the excitation of levels at: 788 +- 23, 982 +- 17, 1088 +- 27, 1335 +- 35, 1504 +- 30, 1697 +- 19, 1971 +- 22, 2176 +- 28, 2456 +- (.), and 2581 +- (.) keV, were observed. An optical-statistical model, giving a good description of the observables, was deduced from the measured differential-elastic-scattering cross sections. The experimental-results were compared with the respective evaluated quantities given in ENDF/B-V

  15. Pion photoproduction cross section at large momentum transfer

    Energy Technology Data Exchange (ETDEWEB)

    Sjoegren, Johan [Univ. of Glasgow, Scotland, United Kingdom

    2015-02-27

    The Real Compton Scattering experiment was performed in Hall A at the Thomas Jefferson National Accelerator Facility. It was designed to measure, for Compton scattering and π0-photoproduction, the differential cross section over a range of kinematic points and the polarisation transfer to the proton at a single kinematic point. The full range of the experiment in Mandelstam variables t and s was 1.6-6.46 GeV2 and 4.82-10.92 GeV2 respectively with beam energies of 2-6 GeV. The motivation for the experiment is to test the cross section and polarisation transfer predictions of perturbative QCD versus that of predictions from Generalised Parton Distribution models. This thesis will give an overview of the pertinent theory, experimental setup in Hall A and the extracting of the π0-photoproduction cross section.

  16. Fast-neutron total and scattering cross sections of niobium

    Energy Technology Data Exchange (ETDEWEB)

    Smith, A.B.; Guenther, P.T.; Whalen, J.F.

    1982-07-01

    Neutron total cross sections of niobium were measured from approx. = 0.7 to 4.5 MeV at intervals of less than or equal to 50 keV with broad resolution. Differential-elastic-scattering cross sections were measured from approx. = 1.5 to 4.0 MeV at intervals of 0.1 to 0.2 MeV and at 10 to 20 scattering angles distributed between approx. = 20 and 160 degrees. Inelastically-scattered neutrons, corresponding to the excitation of levels at: 788 +- 23, 982 +- 17, 1088 +- 27, 1335 +- 35, 1504 +- 30, 1697 +- 19, 1971 +- 22, 2176 +- 28, 2456 +- (.), and 2581 +- (.) keV, were observed. An optical-statistical model, giving a good description of the observables, was deduced from the measured differential-elastic-scattering cross sections. The experimental-results were compared with the respective evaluated quantities given in ENDF/B-V.

  17. Radiative neutron capture cross section from 236U

    Science.gov (United States)

    Baramsai, B.; Jandel, M.; Bredeweg, T. A.; Bond, E. M.; Roman, A. R.; Rusev, G.; Walker, C. L.; Couture, A.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.; Kawano, T.

    2017-08-01

    The 236U(n ,γ ) reaction cross section has been measured for the incident neutron energy range from 10 eV to 800 keV by using the Detector for Advanced Neutron Capture Experiments (DANCE) γ -ray calorimeter at the Los Alamos Neutron Science Center. The cross section was determined with the ratio method, which is a technique that uses the 235U(n ,f ) reaction as a reference. The results of the experiment are reported in the resolved and unresolved resonance energy regions. Individual neutron resonance parameters were obtained below 1 keV incident energy by using the R -matrix code sammy. The cross section in the unresolved resonance region is determined with improved experimental uncertainty. It agrees with both ENDF/B-VII.1 and JEFF-3.2 nuclear data libraries. The results above 10 keV agree better with the JEFF-3.2 library.

  18. Development of Cross Section Library and Application Programming Interface (API)

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C. H. [Argonne National Lab. (ANL), Argonne, IL (United States); Marin-Lafleche, A. [Argonne National Lab. (ANL), Argonne, IL (United States); Smith, M. A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-04-09

    The goal of NEAMS neutronics is to develop a high-fidelity deterministic neutron transport code termed PROTEUS for use on all reactor types of interest, but focused primarily on sodium-cooled fast reactors. While PROTEUS-SN has demonstrated good accuracy for homogeneous fast reactor problems and partially heterogeneous fast reactor problems, the simulation results were not satisfactory when applied on fully heterogeneous thermal problems like the Advanced Test Reactor (ATR). This is mainly attributed to the quality of cross section data for heterogeneous geometries since the conventional cross section generation approach does not work accurately for such irregular and complex geometries. Therefore, one of the NEAMS neutronics tasks since FY12 has been the development of a procedure to generate appropriate cross sections for a heterogeneous geometry core.

  19. Total fusion cross section for the 160+160 system

    International Nuclear Information System (INIS)

    Tserruya, I.; Eisen, Y.; Pelte, D.; Gavron, A.; Oeschler, H.; Berndt, D.; Harney, H.L.

    1978-01-01

    Total fusion cross sections Σsub(F) have been measured for 16 0+ 16 0 at bombarding energies 27-66 MeV using the E-Δ or the time-of-flight techniques. The fusion excitation function shows oscillations in agreement with the resonances produced in the total reaction cross section by a surface-transparent potential. The results are compared to those obtained via the γ-ray technique and th importance of direct decay to ground states is discussed. Mass and total angular distributions are well reproduced by statistical model calculations which take angular momentum into account explicitly. Barrier and critical parameters are extracted from the average energy behavior of Σ sub(F). No evidence for shell effects as predicted by Glas and Mosel is found on the measured fusion cross sections. (author)

  20. Calculation of vibrational excitation cross-sections in resonant ...

    Indian Academy of Sciences (India)

    WINTEC

    grid Hamiltonian (FGH) approach29,30 to ECO(R). In. Figure 2. Calculated cross correlation functions 〈φn|ψ0(t)〉. [(a)–(e)] and corresponding vibrational excitation cross sections σn←0(E) [(f)–(j)] for e-CO scattering. time evolution of the ground vibrational state φ0(R) of the CO target under the influence of CO–Hamiltonian.

  1. Scattering cross section and stability of global monopoles

    Science.gov (United States)

    Pitelli, J. P. M.; Barroso, V. S.; Richartz, Maurício

    2017-11-01

    We study the scattering of scalar waves propagating on the global monopole background. Since the scalar wave operator in this topological defect is not essentially self-adjoint, its solutions are not uniquely determined until a boundary condition at the origin is specified. As we show, this boundary condition manifests itself in the differential cross section and can be inferred by measuring the amplitude of the backscattered wave. We further demonstrate that whether or not the spacetime is stable under scalar perturbations also depends on the chosen boundary condition. In particular, we identify a class of such boundary conditions that significantly affects the differential cross section without introducing an instability.

  2. Activities of the JILA Atomic Collisions Cross Sections Data Center

    International Nuclear Information System (INIS)

    Gallagher, J.W.

    1983-01-01

    The JILA Atomic Collisions Cross Sections Data Center compiles, critically evaluates, and reviews cross sections and rates for low energy (<100 keV) collisions of electrons, photons, and heavy particles with atoms, ions, and simple molecules. Reports are prepared which provide easily accessible recommended data with error limits, list the fundamental literature related to specific topics, identify regions where data are missing, and point out inconsistencies in existing data. The general methodology used in producing evaluated compilations is described. Recently completed projects and work in progress are reported

  3. Research on the display of nuclear cross-section library

    International Nuclear Information System (INIS)

    Huang Shien; Wang Kan; Yu Ganglin

    2008-01-01

    Minutely parsed the dot cross-section format (ACE format) data of the ENDF/ B-6.8 database, which is the foundation of the program that achieved the reading and related handling of ACE format data. This program achieved the plotting, zooming and comparing display functions of nuclear cross section-energy of ENDF/B-6.8 database. It also provides the standard picture formatting file output and/or standard text formatting file output of interesting nuclear data. It accomplished some appropriate validations of this program via the comparing between program results and reference data. (authors)

  4. Review of multigroup nuclear cross-section processing

    Energy Technology Data Exchange (ETDEWEB)

    Trubey, D.K.; Hendrickson, H.R. (comps.)

    1978-10-01

    These proceedings consist of 18 papers given at a seminar--workshop on ''Multigroup Nuclear Cross-Section Processing'' held at Oak Ridge, Tennessee, March 14--16, 1978. The papers describe various computer code systems and computing algorithms for producing multigroup neutron and gamma-ray cross sections from evaluated data, and experience with several reference data libraries. Separate abstracts were prepared for 13 of the papers. The remaining five have already been cited in ERA, and may be located by referring to the entry CONF-780334-- in the Report Number Index. (RWR)

  5. SU-E-I-43: Photoelectric Cross Section Revisited

    International Nuclear Information System (INIS)

    Haga, A; Nakagawa, K; Kotoku, J; Horikawa, Y

    2015-01-01

    Purpose: The importance of the precision in photoelectric cross-section value increases for recent developed technology such as dual energy computed tomography, in which some reconstruction algorithms require the energy dependence of the photo-absorption in each material composition of human being. In this study, we revisited the photoelectric cross-section calculation by self-consistent relativistic Hartree-Fock (HF) atomic model and compared with that widely distributed as “XCOM database” in National Institute of Standards and Technology, which was evaluated with localdensity approximation for electron-exchange (Fock)z potential. Methods: The photoelectric cross section can be calculated with the electron wave functions in initial atomic state (bound electron) and final continuum state (photoelectron). These electron states were constructed based on the selfconsistent HF calculation, where the repulsive Coulomb potential from the electron charge distribution (Hartree term) and the electron exchange potential with full electromagnetic interaction (Fock term) were included for the electron-electron interaction. The photoelectric cross sections were evaluated for He (Z=2), Be (Z=4), C (Z=6), O (Z=8), and Ne (Z=10) in energy range of 10keV to 1MeV. The Result was compared with XCOM database. Results: The difference of the photoelectric cross section between the present calculation and XCOM database was 8% at a maximum (in 10keV for Be). The agreement tends to be better as the atomic number increases. The contribution from each atomic shell has a considerable discrepancy with XCOM database except for K-shell. However, because the photoelectric cross section arising from K-shell is dominant, the net photoelectric cross section was almost insensitive to the different handling in Fock potential. Conclusion: The photoelectric cross-section program has been developed based on the fully self-consistent relativistic HF atomic model. Due to small effect on the Fock

  6. Determination of Ultimate Torque for Multiply Connected Cross Section Rod

    Directory of Open Access Journals (Sweden)

    V. L. Danilov

    2015-01-01

    Full Text Available The aim of this work is to determine load-carrying capability of the multiply cross-section rod. This calculation is based on the model of the ideal plasticity of the material, so that the desired ultimate torque is a torque at which the entire cross section goes into a plastic state.The article discusses the cylindrical multiply cross-section rod. To satisfy the equilibrium equation and the condition of plasticity simultaneously, two stress function Ф and φ are introduced. By mathematical transformations it has been proved that Ф is constant along the path, and a formula to find its values on the contours has been obtained. The paper also presents the rationale of the line of stress discontinuity and obtained relationships, which allow us to derive the equations break lines for simple interaction of neighboring circuits, such as two lines, straight lines and circles, circles and a different sign of the curvature.After substitution into the boundary condition at the end of the stress function Ф and mathematical transformations a formula is obtained to determine the ultimate torque for the multiply cross-section rod.Using the doubly connected cross-section and three-connected cross-section rods as an example the application of the formula of ultimate torque is studied.For doubly connected cross-section rod, the paper offers a formula of the torque versus the radius of the rod, the aperture radius and the distance between their centers. It also clearly demonstrates the torque dependence both on the ratio of the radii and on the displacement of hole. It is shown that the value of the torque is more influenced by the displacement of hole, rather than by the ratio of the radii.For the three-connected cross-section rod the paper shows the integration feature that consists in selection of a coordinate system. As an example, the ultimate torque is found by two methods: analytical one and 3D modeling. The method of 3D modeling is based on the Nadai

  7. Electron transport in silicon nanowires having different cross-sections

    Directory of Open Access Journals (Sweden)

    Muscato Orazio

    2016-06-01

    Full Text Available Transport phenomena in silicon nanowires with different cross-section are investigated using an Extended Hydrodynamic model, coupled to the Schrödinger-Poisson system. The model has been formulated by closing the moment system derived from the Boltzmann equation on the basis of the maximum entropy principle of Extended Thermodynamics, obtaining explicit closure relations for the high-order fluxes and the production terms. Scattering of electrons with acoustic and non polar optical phonons have been taken into account. The bulk mobility is evaluated for square and equilateral triangle cross-sections of the wire.

  8. Geodesic acoustic modes in noncircular cross section tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Sorokina, E. A., E-mail: sorokina.ekaterina@gmail.com; Lakhin, V. P. [National Research Center “Kurchatov Institute,” (Russian Federation); Konovaltseva, L. V. [People’s Friendship University of Russia (Russian Federation); Ilgisonis, V. I. [National Research Center “Kurchatov Institute,” (Russian Federation)

    2017-03-15

    The influence of the shape of the plasma cross section on the continuous spectrum of geodesic acoustic modes (GAMs) in a tokamak is analyzed in the framework of the MHD model. An expression for the frequency of a local GAM for a model noncircular cross section plasma equilibrium is derived. Amendments to the oscillation frequency due to the plasma elongation and triangularity and finite tokamak aspect ratio are calculated. It is shown that the main factor affecting the GAM spectrum is the plasma elongation, resulting in a significant decrease in the mode frequency.

  9. Emission and absorption cross section of thulium doped silica fibers

    DEFF Research Database (Denmark)

    Agger, Søren Dyøe; Povlsen, Jørn Hedegaard

    2006-01-01

    A thorough investigation of the emission and absorption spectra of the (F-3(4),H-3(6)) band in thulium doped silica fibers has been performed. All the basic parameters of thulium in silica have been extracted with the purpose of further analysis in laser and amplifier simulations. The experimental...... methods used to obtain the scaled cross sections have been carefully selected in order to avoid problems associated with calibrated measurements and knowledge of the radiative lifetime. The values of the absorption cross sections agree well with previously reported values, however the peak emission...

  10. Electromagnetic Cylindrical Transparent Devices with Irregular Cross Section

    Directory of Open Access Journals (Sweden)

    C. Yang

    2010-04-01

    Full Text Available Electromagnetic transparent device is very important for antenna protection. In this paper, the material parameters for the cylindrical transparent devices with arbitrary cross section are developed based on the coordinate transformation. The equivalent two-dimensional (2D transparent devices under TE plane and cylindrical wave irradiation is designed and studied by full-wave simulation, respectively. It shows that although the incident waves are distorted in the transformation region apparently, they return to the original wavefronts when passing through the device. All theoretical and numerical results validate the material parameters for the cylindrical transparent devices with arbitrary cross section we developed.

  11. PCS a code system for generating production cross section libraries

    International Nuclear Information System (INIS)

    Cox, L.J.

    1997-01-01

    This document outlines the use of the PCS Code System. It summarizes the execution process for generating FORMAT2000 production cross section files from FORMAT2000 reaction cross section files. It also describes the process of assembling the ASCII versions of the high energy production files made from ENDL and Mark Chadwick's calculations. Descriptions of the function of each code along with its input and output and use are given. This document is under construction. Please submit entries, suggestions, questions, and corrections to (ljc at sign llnl.gov) 3 tabs

  12. Inelastic cross sections from gamma-ray measurements

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Ronald Owen [Los Alamos National Laboratory

    2010-12-06

    Measurements of gamma rays following neutron induced reactions have been studied with the Germanium Array for Neutron-induced Excitations (GEANIE) at the Los Alamos Neutron Science Center (LANSCE) for many years. Gamma-ray excitation functions and coincidence studies provide insight into nuclear reaction mechanisms as well as expanding our knowledge of energy levels and gamma-rays. Samples studied with Ge detectors at LANSCE range from Be to Pu. Fe, Cr and Ti have been considered for use as reference cross sections. An overview of the measurements and efforts to create a reliable neutron-induced gamma-ray reference cross section will be presented.

  13. D meson branching ratios and hadronic charm production cross sections

    International Nuclear Information System (INIS)

    Aguilar-Benitez, M.; Ferrando, A.; Hernandez, J.; Allison, W.W.M.; Hughes, P.T.; Bagnaia, P.; Bizzarri, R.; Ciapetti, G.; Di Capua, E.; Gentile, S.; Iori, M.; Marzano, F.; Piredda, G.; Zanello, L.; Baland, J.; Herquet, P.; Pilette, P.; Poiret, C.; Bettini, A.; Checchia, P.; Gasparini, U.; Mazzucato, M.; Pinori, C.; Ventura, L.; Zotto, P.; Zumerle, G.; Boratov, M.; Duboc, J.; Nguyen, H.; Touchard, A.M.; Bruyant, F.; Dumarchez, J.; Johansson, K.E.; Leutz, H.; Montanet, L.; Nilsson, S.; Poppleton, A.; Reucroft, S.; Richardson, J.; Subramanian, A.; Touboul, M.C.; Wright, P.R.S.; Castelli, E.; Poropat, P.; Sessa, M.; Troncon, C.; Crennell, D.; Fisher, C.; MacDermott, M.; Kittel, W.; Stergiou, A.; Toet, D.; Bertrand-Coremans, G.; Lemonne, J.; Immerseel, M. van; Vilain, P.; Vonck, B.; Wickens, J.

    1984-01-01

    A determination of branching ratios for D meson decays into all charged particle final states is reported. The values obtained :(D + -> Ksup(+-)πsup(+-)πsup(+-)/all Dsup(+-)) = (14 +- 6)% and (anti D 0 /D 0 -> Ksup(+-)πsup(+-)ππ + π - /all anti D 0 /D 0 ) = (10 +- 4)%, are higher than those currently accepted. This result, if confirmed, implies a corresponding reduction in the accepted values for some total cross section measurements. Revised inclusive cross sections for D meson production in the forward hemisphere in π - p and pp interactions at 360 GeV/c, are presented. (orig.)

  14. Measurement of the W + Jets Production Cross Section with ATLAS

    CERN Document Server

    Jen-La Plante, I; The ATLAS collaboration

    2011-01-01

    The associated production of jets with a W-boson provides a proving ground for perturbative QCD predictions and an important background to other interesting processes in the Standard Model and beyond. In both the electron and muon decay modes of the W-boson, measurements using the ATLAS detector are presented. These include cross sections as a function of jet multiplicity, jet transverse momentum, and the sum of transverse momenta of energetic jets and leptons in each event, as well as ratios of cross sections. The results are corrected to particle level and compared with predictions from Monte Carlo simulations and next-to-leading order perturbative QCD calculations.

  15. Measurement of the W + Jets Production Cross Section with ATLAS

    CERN Document Server

    Jen-La Plante, I; The ATLAS collaboration

    2011-01-01

    The associated production of jets with a W-boson provides a proving ground for perturbative QCD predictions and a formidable background to other interesting processes in the Standard Model and beyond. In both the electron and muon decay modes of the W-boson, measurements using the ATLAS detector are presented. These include cross sections as a function of jet multiplicity, jet transverse momentum, and the sum of transverse momenta of energetic jets and leptons in each event, as well as ratios of cross sections. The results are corrected to particle level and compared with predictions from Monte Carlo simulations and next-to-leading order perturbative QCD calculations.

  16. Fast-neutron scattering cross sections of elemental zirconium

    International Nuclear Information System (INIS)

    Smith, A.B.; Guenther, P.T.

    1982-12-01

    Differential neturon-elastic-scattering cross sections of elemental zirconium are measured from 1.5 to 4.0 MeV at intervals of less than or equal to 200 keV. Inelastic-neutron-scattering cross sections corresponding to the excitation of levels at observed energies of: 914 +- 25, 1476 +- 37, 1787 +- 23, 2101 +- 26, 2221 +- 17, 2363 +- 14, 2791 +- 15 and 3101 +- 25 keV are determined. The experimental results are interpreted in terms of the optical-statistical model and are compared with corresponding quantities given in ENDF/B-V

  17. Evaluation of the 238U neutron total cross section

    International Nuclear Information System (INIS)

    Smith, A.; Poenitz, W.P.; Howerton, R.J.

    1982-12-01

    Experimental energy-averaged neutron total cross sections of 238 U were evaluated from 0.044 to 20.0 MeV using regorous numerical methods. The evaluated results are presented together with the associated uncertainties and correlation matrix. They indicate that this energy-averaged neutron total cross section is known to better than 1% over wide energy regions. There are somwewhat larger uncertainties at low energies (e.g., less than or equal to 0.2 MeV), near 8 MeV and above 15 MeV. The present evaluation is compard with values given in ENDF/B-V

  18. Continuum effects in electron-helium total cross sections

    International Nuclear Information System (INIS)

    McCarthy, I.E.; Ratnavelu, K.; Weigold, A.M.

    1988-06-01

    It is shown that total cross sections for the excitation of target states with large spectroscopic factors may be calculated accurately by representing the states by their leading independent-particle configurations. With this approximation coupled channels calculations agree only qualitatively with experimental total cross sections for the first five states of helium. R-matrix calculations using configuration interaction show better qualitative agreement. The complex polarisation potential for continuum excitations is described for two-electron atoms. When this is included in a coupled-channels optical calculation quantitative agreement with experiment is obtained for most states at 30, 50 and 100eV

  19. Partial photoneutron cross section measurements on 209Bi

    Directory of Open Access Journals (Sweden)

    Gheorghe Ioana

    2017-01-01

    Full Text Available New data of total and partial (γ,xn cross sections with x = 1–3 are proposed to be measured by direct neutron multiplicity sorting using Laser Compton scattering (LCS gamma ray beams at the ELI-NP to solve long standing discrepancies between existing Lawrence Livermore National Laboratory (USA and France Centre d'Etudes Nucleaires de Saclay photonuclear data. Pioneering experiments are currently performed at the NewSUBARU facility. We present here preliminary results on 209Bi(g,xn cross section measurements.

  20. New SCALE-4 features related to cross-section processing

    International Nuclear Information System (INIS)

    Petrie, L.M.; Landers, N.F.; Greene, N.M.; Parks, C.V.

    1991-01-01

    The SCALE code system has a standardized scheme for processing problem-dependent cross section from problem-independent waste libraries. Some improvements and new capabilities in the processing scheme have been incorporated into the new Version 4 release of the SCALE system. The new features include the capability to consider annular cylindrical and spherical unit cells, and improved Dancoff factor formulation, and changes to the NITAWL-II module to perform resonance self-shielding with reference to infinite dilute values. A review of these major changes in the cross-section processing scheme for SCALE-4 is presented in this paper

  1. Top quark pair cross section measurements in CMS

    CERN Document Server

    Brochero Cifuentes, Javier Andres

    2016-01-01

    This document presents the latest results in the measurement of the top-quark pair production cross section obtained with data collected by the CMS detector at LHC accelerator. The analyses are performed in the dilepton, single lepton and full hadronic decay modes. Additionally to the inclusive measurements of $\\mathrm{\\sigma_{\\mathrm{t\\bar{t}}}}$ at 7, 8 and 13$\\mathrm{\\;TeV}$, the CMS collaboration provides for the first time the cross section at 5.02$\\mathrm{\\;TeV}$. Results are confronted with the latest and most precise theoretical calculations.

  2. Total reaction cross section calculations in proton-nucleus scattering

    International Nuclear Information System (INIS)

    Wellisch, H.P.; Axen, D.

    1996-01-01

    We have developed a general semiempirical total reaction cross section formula for proton-nucleus reactions. It is applicable for all materials with nuclear charge Z greater than 5, and all proton kinetic energies from the lowest measured energies up to ≅20 GeV. While the regime of applicability is greatly enlarged, agreement between the calculated cross sections and the experimental data is comparable to or better than all earlier published results in their regime of applicability. copyright 1996 The American Physical Society

  3. Inclusive jet cross sections and jet shapes at CDF

    International Nuclear Information System (INIS)

    Wainer, N.

    1991-09-01

    The inclusive jet cross section and jet shapes at √s = 1.8 TeV have been measured by CDF at the Fermilab Tevatron Collider. results are compared to recent next-to-leading order QCD calculations, which predict variation of the cross section with cone size, as well as variation of the jet shape with energy. A lower limit on the parameter Λ c , which characterize a contact interaction associated with quark sub-structure is determined to be 1400 GeV at the 95% confidence level. 3 refs., 4 figs

  4. Propagation of sound waves in tubes of noncircular cross section

    Science.gov (United States)

    Richards, W. B.

    1986-01-01

    Plane-acoustic-wave propagation in small tubes with a cross section in the shape of a flattened oval is described. Theoretical descriptions of a plane wave propagating in a tube with circular cross section and between a pair of infinite parallel plates, including viscous and thermal damping, are expressed in similar form. For a wide range of useful duct sizes, the propagation constant (whose real and imaginary parts are the amplitude attenuation rate and the wave number, respectively) is very nearly the same function of frequency for both cases if the radius of the circular tube is the same as the distance between the parallel plates. This suggests that either a circular-cross-section model or a flat-plate model can be used to calculate wave propagation in flat-oval tubing, or any other shape tubing, if its size is expressed in terms of an equivalent radius, given by g = 2 x (cross-sectional area)/(length of perimeter). Measurements of the frequency response of two sections of flat-oval tubing agree with calculations based on this idea. Flat-plate formulas are derived, the use of transmission-line matrices for calculations of plane waves in compound systems of ducts is described, and examples of computer programs written to carry out the calculations are shown.

  5. Upsilon production cross section in pp collisions at $\\sqrt{s}$ = 7 TeV

    CERN Document Server

    Khachatryan, Vardan; Tumasyan, Armen; Adam, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hammer, Josef; Haensel, Stephan; Hartl, Christian; Hoch, Michael; Hörmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kasieczka, Gregor; Kiesenhofer, Wolfgang; Krammer, Manfred; Liko, Dietrich; Mikulec, Ivan; Pernicka, Manfred; Rohringer, Herbert; Schöfbeck, Robert; Strauss, Josef; Taurok, Anton; Teischinger, Florian; Waltenberger, Wolfgang; Walzel, Gerhard; Widl, Edmund; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Benucci, Leonardo; Ceard, Ludivine; Cerny, Karel; De Wolf, Eddi A.; Janssen, Xavier; Maes, Thomas; Mucibello, Luca; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Selvaggi, Michele; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Adler, Volker; Beauceron, Stephanie; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Devroede, Olivier; Gonzalez Suarez, Rebeca; Kalogeropoulos, Alexis; Maes, Joris; Maes, Michael; Tavernier, Stefaan; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Charaf, Otman; Clerbaux, Barbara; De Lentdecker, Gilles; Dero, Vincent; Gay, Arnaud; Hammad, Gregory Habib; Hreus, Tomas; Marage, Pierre Edouard; Thomas, Laurent; Vander Velde, Catherine; Vanlaer, Pascal; Wickens, John; Costantini, Silvia; Grunewald, Martin; Klein, Benjamin; Marinov, Andrey; Mccartin, Joseph; Ryckbosch, Dirk; Thyssen, Filip; Tytgat, Michael; Vanelderen, Lukas; Verwilligen, Piet; Walsh, Sinead; Zaganidis, Nicolas; Basegmez, Suzan; Bruno, Giacomo; Caudron, Julien; De Favereau De Jeneret, Jerome; Delaere, Christophe; Demin, Pavel; Favart, Denis; Giammanco, Andrea; Grégoire, Ghislain; Hollar, Jonathan; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Ovyn, Severine; Pagano, Davide; Pin, Arnaud; Piotrzkowski, Krzysztof; Quertenmont, Loic; Schul, Nicolas; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Alves, Gilvan; De Jesus Damiao, Dilson; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Carvalho, Wagner; Melo Da Costa, Eliza; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Mundim, Luiz; Nogima, Helio; Oguri, Vitor; Prado Da Silva, Wanda Lucia; Santoro, Alberto; Silva Do Amaral, Sheila Mara; Sznajder, Andre; De Almeida Dias, Flavia; Ferreira Dias, Marco Andre; Tomei, Thiago; De Moraes Gregores, Eduardo; Da Cunha Marinho, Franciole; Novaes, Sergio F.; Padula, Sandra; Darmenov, Nikolay; Dimitrov, Lubomir; Genchev, Vladimir; Iaydjiev, Plamen; Piperov, Stefan; Rodozov, Mircho; Stoykova, Stefka; Sultanov, Georgi; Tcholakov, Vanio; Trayanov, Rumen; Vankov, Ivan; Dyulendarova, Milena; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Marinova, Evelina; Mateev, Matey; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Wang, Jian; Wang, Jian; Wang, Xianyou; Wang, Zheng; Xu, Ming; Yang, Min; Zang, Jingjing; Zhang, Zhen; Ban, Yong; Guo, Shuang; Li, Wenbo; Mao, Yajun; Qian, Si-Jin; Teng, Haiyun; Zhang, Linlin; Zhu, Bo; Cabrera, Andrés; Gomez Moreno, Bernardo; Ocampo Rios, Alberto Andres; Osorio Oliveros, Andres Felipe; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Lelas, Karlo; Plestina, Roko; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Dzelalija, Mile; Brigljevic, Vuko; Duric, Senka; Kadija, Kreso; Morovic, Srecko; Attikis, Alexandros; Galanti, Mario; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A.; Rykaczewski, Hans; Assran, Yasser; Mahmoud, Mohammed; Hektor, Andi; Kadastik, Mario; Kannike, Kristjan; Müntel, Mait; Raidal, Martti; Rebane, Liis; Azzolini, Virginia; Eerola, Paula; Czellar, Sandor; Härkönen, Jaakko; Heikkinen, Mika Aatos; Karimäki, Veikko; Kinnunen, Ritva; Klem, Jukka; Kortelainen, Matti J.; Lampén, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindén, Tomas; Luukka, Panja-Riina; Mäenpää, Teppo; Tuominen, Eija; Tuominiemi, Jorma; Tuovinen, Esa; Ungaro, Donatella; Wendland, Lauri; Banzuzi, Kukka; Korpela, Arja; Tuuva, Tuure; Sillou, Daniel; Besancon, Marc; Choudhury, Somnath; Dejardin, Marc; Denegri, Daniel; Fabbro, Bernard; Faure, Jean-Louis; Ferri, Federico; Ganjour, Serguei; Gentit, François-Xavier; Givernaud, Alain; Gras, Philippe; Hamel de Monchenault, Gautier; Jarry, Patrick; Locci, Elizabeth; Malcles, Julie; Marionneau, Matthieu; Millischer, Laurent; Rander, John; Rosowsky, André; Shreyber, Irina; Titov, Maksym; Verrecchia, Patrice; Baffioni, Stephanie; Beaudette, Florian; Bianchini, Lorenzo; Bluj, Michal; Broutin, Clementine; Busson, Philippe; Charlot, Claude; Dahms, Torsten; Dobrzynski, Ludwik; Granier de Cassagnac, Raphael; Haguenauer, Maurice; Miné, Philippe; Mironov, Camelia; Ochando, Christophe; Paganini, Pascal; Sabes, David; Salerno, Roberto; Sirois, Yves; Thiebaux, Christophe; Wyslouch, Bolek; Zabi, Alexandre; Agram, Jean-Laurent; Andrea, Jeremy; Besson, Auguste; Bloch, Daniel; Bodin, David; Brom, Jean-Marie; Cardaci, Marco; Chabert, Eric Christian; Collard, Caroline; Conte, Eric; Drouhin, Frédéric; Ferro, Cristina; Fontaine, Jean-Charles; Gelé, Denis; Goerlach, Ulrich; Greder, Sebastien; Juillot, Pierre; Karim, Mehdi; Le Bihan, Anne-Catherine; Mikami, Yoshinari; Van Hove, Pierre; Fassi, Farida; Mercier, Damien; Baty, Clement; Beaupere, Nicolas; Bedjidian, Marc; Bondu, Olivier; Boudoul, Gaelle; Boumediene, Djamel; Brun, Hugues; Chanon, Nicolas; Chierici, Roberto; Contardo, Didier; Depasse, Pierre; El Mamouni, Houmani; Falkiewicz, Anna; Fay, Jean; Gascon, Susan; Ille, Bernard; Kurca, Tibor; Le Grand, Thomas; Lethuillier, Morgan; Mirabito, Laurent; Perries, Stephane; Sordini, Viola; Tosi, Silvano; Tschudi, Yohann; Verdier, Patrice; Xiao, Hong; Roinishvili, Vladimir; Anagnostou, Georgios; Edelhoff, Matthias; Feld, Lutz; Heracleous, Natalie; Hindrichs, Otto; Jussen, Ruediger; Klein, Katja; Merz, Jennifer; Mohr, Niklas; Ostapchuk, Andrey; Perieanu, Adrian; Raupach, Frank; Sammet, Jan; Schael, Stefan; Sprenger, Daniel; Weber, Hendrik; Weber, Martin; Wittmer, Bruno; Ata, Metin; Bender, Walter; Erdmann, Martin; Frangenheim, Jens; Hebbeker, Thomas; Hinzmann, Andreas; Hoepfner, Kerstin; Hof, Carsten; Klimkovich, Tatsiana; Klingebiel, Dennis; Kreuzer, Peter; Lanske, Dankfried; Magass, Carsten; Masetti, Gianni; Merschmeyer, Markus; Meyer, Arnd; Papacz, Paul; Pieta, Holger; Reithler, Hans; Schmitz, Stefan Antonius; Sonnenschein, Lars; Steggemann, Jan; Teyssier, Daniel; Bontenackels, Michael; Davids, Martina; Duda, Markus; Flügge, Günter; Geenen, Heiko; Giffels, Manuel; Haj Ahmad, Wael; Heydhausen, Dirk; Kress, Thomas; Kuessel, Yvonne; Linn, Alexander; Nowack, Andreas; Perchalla, Lars; Pooth, Oliver; Rennefeld, Jörg; Sauerland, Philip; Stahl, Achim; Thomas, Maarten; Tornier, Daiske; Zoeller, Marc Henning; Aldaya Martin, Maria; Behrenhoff, Wolf; Behrens, Ulf; Bergholz, Matthias; Borras, Kerstin; Cakir, Altan; Campbell, Alan; Castro, Elena; Dammann, Dirk; Eckerlin, Guenter; Eckstein, Doris; Flossdorf, Alexander; Flucke, Gero; Geiser, Achim; Glushkov, Ivan; Hauk, Johannes; Jung, Hannes; Kasemann, Matthias; Katkov, Igor; Katsas, Panagiotis; Kleinwort, Claus; Kluge, Hannelies; Knutsson, Albert; Krücker, Dirk; Kuznetsova, Ekaterina; Lange, Wolfgang; Lohmann, Wolfgang; Mankel, Rainer; Marienfeld, Markus; Melzer-Pellmann, Isabell-Alissandra; Meyer, Andreas Bernhard; Mnich, Joachim; Mussgiller, Andreas; Olzem, Jan; Parenti, Andrea; Raspereza, Alexei; Raval, Amita; Schmidt, Ringo; Schoerner-Sadenius, Thomas; Sen, Niladri; Stein, Matthias; Tomaszewska, Justyna; Volyanskyy, Dmytro; Walsh, Roberval; Wissing, Christoph; Autermann, Christian; Bobrovskyi, Sergei; Draeger, Jula; Enderle, Holger; Gebbert, Ulla; Kaschube, Kolja; Kaussen, Gordon; Klanner, Robert; Lange, Jörn; Mura, Benedikt; Naumann-Emme, Sebastian; Nowak, Friederike; Pietsch, Niklas; Sander, Christian; Schettler, Hannes; Schleper, Peter; Schröder, Matthias; Schum, Torben; Schwandt, Joern; Srivastava, Ajay Kumar; Stadie, Hartmut; Steinbrück, Georg; Thomsen, Jan; Wolf, Roger; Barth, Christian; Bauer, Julia; Buege, Volker; Chwalek, Thorsten; De Boer, Wim; Dierlamm, Alexander; Dirkes, Guido; Feindt, Michael; Gruschke, Jasmin; Hackstein, Christoph; Hartmann, Frank; Heindl, Stefan Michael; Heinrich, Michael; Held, Hauke; Hoffmann, Karl-Heinz; Honc, Simon; Kuhr, Thomas; Martschei, Daniel; Mueller, Steffen; Müller, Thomas; Niegel, Martin; Oberst, Oliver; Oehler, Andreas; Ott, Jochen; Peiffer, Thomas; Piparo, Danilo; Quast, Gunter; Rabbertz, Klaus; Ratnikov, Fedor; Renz, Manuel; Saout, Christophe; Scheurer, Armin; Schieferdecker, Philipp; Schilling, Frank-Peter; Schott, Gregory; Simonis, Hans-Jürgen; Stober, Fred-Markus Helmut; Troendle, Daniel; Wagner-Kuhr, Jeannine; Zeise, Manuel; Zhukov, Valery; Ziebarth, Eva Barbara; Daskalakis, Georgios; Geralis, Theodoros; Kesisoglou, Stilianos; Kyriakis, Aristotelis; Loukas, Demetrios; Manolakos, Ioannis; Markou, Athanasios; Markou, Christos; Mavrommatis, Charalampos; Petrakou, Eleni; Gouskos, Loukas; Mertzimekis, Theodoros; Panagiotou, Apostolos; Evangelou, Ioannis; Foudas, Costas; Kokkas, Panagiotis; Manthos, Nikolaos; Papadopoulos, Ioannis; Patras, Vaios; Triantis, Frixos A.; Aranyi, Attila; Bencze, Gyorgy; Boldizsar, Laszlo; Debreczeni, Gergely; Hajdu, Csaba; Horvath, Dezso; Kapusi, Anita; Krajczar, Krisztian; Laszlo, Andras; Sikler, Ferenc; Vesztergombi, Gyorgy; Beni, Noemi; Molnar, Jozsef; Palinkas, Jozsef; Szillasi, Zoltan; Veszpremi, Viktor; Raics, Peter; Trocsanyi, Zoltan Laszlo; Ujvari, Balazs; Bansal, Sunil; Beri, Suman Bala; Bhatnagar, Vipin; Dhingra, Nitish; Jindal, Monika; Kaur, Manjit; Kohli, Jatinder Mohan; Mehta, Manuk Zubin; Nishu, Nishu; Saini, Lovedeep Kaur; Sharma, Archana; Singh, Anil; Singh, Jas Bir; Singh, Supreet Pal; Ahuja, Sudha; Bhattacharya, Satyaki; Choudhary, Brajesh C.; Gupta, Pooja; Jain, Sandhya; Jain, Shilpi; Kumar, Ashok; Shivpuri, Ram Krishen; Choudhury, Rajani Kant; Dutta, Dipanwita; Kailas, Swaminathan; Kataria, Sushil Kumar; Mohanty, Ajit Kumar; Pant, Lalit Mohan; Shukla, Prashant; Suggisetti, Praveenkumar; Aziz, Tariq; Guchait, Monoranjan; Gurtu, Atul; Maity, Manas; Majumder, Devdatta; Majumder, Gobinda; Mazumdar, Kajari; Mohanty, Gagan Bihari; Saha, Anirban; Sudhakar, Katta; Wickramage, Nadeesha; Banerjee, Sudeshna; Dugad, Shashikant; Mondal, Naba Kumar; Arfaei, Hessamaddin; Bakhshiansohi, Hamed; Etesami, Seyed Mohsen; Fahim, Ali; Hashemi, Majid; Jafari, Abideh; Khakzad, Mohsen; Mohammadi, Abdollah; Mohammadi Najafabadi, Mojtaba; Paktinat Mehdiabadi, Saeid; Safarzadeh, Batool; Zeinali, Maryam; Abbrescia, Marcello; Barbone, Lucia; Calabria, Cesare; Colaleo, Anna; Creanza, Donato; De Filippis, Nicola; De Palma, Mauro; Dimitrov, Anton; Fiore, Luigi; Iaselli, Giuseppe; Lusito, Letizia; Maggi, Giorgio; Maggi, Marcello; Manna, Norman; Marangelli, Bartolomeo; My, Salvatore; Nuzzo, Salvatore; Pacifico, Nicola; Pierro, Giuseppe Antonio; Pompili, Alexis; Pugliese, Gabriella; Romano, Francesco; Roselli, Giuseppe; Selvaggi, Giovanna; Silvestris, Lucia; Trentadue, Raffaello; Tupputi, Salvatore; Zito, Giuseppe; Abbiendi, Giovanni; Benvenuti, Alberto; Bonacorsi, Daniele; Braibant-Giacomelli, Sylvie; Capiluppi, Paolo; Castro, Andrea; Cavallo, Francesca Romana; Cuffiani, Marco; Dallavalle, Gaetano-Marco; Fabbri, Fabrizio; Fanfani, Alessandra; Fasanella, Daniele; Giacomelli, Paolo; Giunta, Marina; Grandi, Claudio; Marcellini, Stefano; Meneghelli, Marco; Montanari, Alessandro; Navarria, Francesco; Odorici, Fabrizio; Perrotta, Andrea; Primavera, Federica; Rossi, Antonio; Rovelli, Tiziano; Siroli, Gianni; Travaglini, Riccardo; Albergo, Sebastiano; Cappello, Gigi; Chiorboli, Massimiliano; Costa, Salvatore; Tricomi, Alessia; Tuve, Cristina; Barbagli, Giuseppe; Ciulli, Vitaliano; Civinini, Carlo; D'Alessandro, Raffaello; Focardi, Ettore; Frosali, Simone; Gallo, Elisabetta; Genta, Chiara; Lenzi, Piergiulio; Meschini, Marco; Paoletti, Simone; Sguazzoni, Giacomo; Tropiano, Antonio; Benussi, Luigi; Bianco, Stefano; Colafranceschi, Stefano; Fabbri, Franco; Piccolo, Davide; Fabbricatore, Pasquale; Musenich, Riccardo; Benaglia, Andrea; De Guio, Federico; Di Matteo, Leonardo; Ghezzi, Alessio; Malberti, Martina; Malvezzi, Sandra; Martelli, Arabella; Massironi, Andrea; Menasce, Dario; Moroni, Luigi; Paganoni, Marco; Pedrini, Daniele; Ragazzi, Stefano; Redaelli, Nicola; Sala, Silvano; Tabarelli de Fatis, Tommaso; Tancini, Valentina; Buontempo, Salvatore; Carrillo Montoya, Camilo Andres; Cimmino, Anna; De Cosa, Annapaola; De Gruttola, Michele; Fabozzi, Francesco; Iorio, Alberto Orso Maria; Lista, Luca; Merola, Mario; Noli, Pasquale; Paolucci, Pierluigi; Azzi, Patrizia; Bacchetta, Nicola; Bellan, Paolo; Bisello, Dario; Branca, Antonio; Carlin, Roberto; Checchia, Paolo; De Mattia, Marco; Dorigo, Tommaso; Dosselli, Umberto; Fanzago, Federica; Gasparini, Fabrizio; Gasparini, Ugo; Giubilato, Piero; Gresele, Ambra; Lacaprara, Stefano; Lazzizzera, Ignazio; Margoni, Martino; Mazzucato, Mirco; Meneguzzo, Anna Teresa; Nespolo, Massimo; Perrozzi, Luca; Pozzobon, Nicola; Ronchese, Paolo; Simonetto, Franco; Torassa, Ezio; Tosi, Mia; Vanini, Sara; Zotto, Pierluigi; Zumerle, Gianni; Baesso, Paolo; Berzano, Umberto; Riccardi, Cristina; Torre, Paola; Vitulo, Paolo; Viviani, Claudio; Biasini, Maurizio; Bilei, Gian Mario; Caponeri, Benedetta; Fanò, Livio; Lariccia, Paolo; Lucaroni, Andrea; Mantovani, Giancarlo; Menichelli, Mauro; Nappi, Aniello; Santocchia, Attilio; Servoli, Leonello; Taroni, Silvia; Valdata, Marisa; Volpe, Roberta; Azzurri, Paolo; Bagliesi, Giuseppe; Bernardini, Jacopo; Boccali, Tommaso; Broccolo, Giuseppe; Castaldi, Rino; D'Agnolo, Raffaele Tito; Dell'Orso, Roberto; Fiori, Francesco; Foà, Lorenzo; Giassi, Alessandro; Kraan, Aafke; Ligabue, Franco; Lomtadze, Teimuraz; Martini, Luca; Messineo, Alberto; Palla, Fabrizio; Palmonari, Francesco; Sarkar, Subir; Serban, Alin Titus; Spagnolo, Paolo; Tenchini, Roberto; Tonelli, Guido; Venturi, Andrea; Verdini, Piero Giorgio; Barone, Luciano; Cavallari, Francesca; Del Re, Daniele; Di Marco, Emanuele; Diemoz, Marcella; Franci, Daniele; Grassi, Marco; Longo, Egidio; Organtini, Giovanni; Palma, Alessandro; Pandolfi, Francesco; Paramatti, Riccardo; Rahatlou, Shahram; Amapane, Nicola; Arcidiacono, Roberta; Argiro, Stefano; Arneodo, Michele; Biino, Cristina; Botta, Cristina; Cartiglia, Nicolo; Castello, Roberto; Costa, Marco; Demaria, Natale; Graziano, Alberto; Mariotti, Chiara; Marone, Matteo; Maselli, Silvia; Migliore, Ernesto; Mila, Giorgia; Monaco, Vincenzo; Musich, Marco; Obertino, Maria Margherita; Pastrone, Nadia; Pelliccioni, Mario; Romero, Alessandra; Ruspa, Marta; Sacchi, Roberto; Sola, Valentina; Solano, Ada; Staiano, Amedeo; Trocino, Daniele; Vilela Pereira, Antonio; Ambroglini, Filippo; Belforte, Stefano; Cossutti, Fabio; Della Ricca, Giuseppe; Gobbo, Benigno; Montanino, Damiana; Penzo, Aldo; Heo, Seong Gu; Chang, Sunghyun; Chung, Jin Hyuk; Kim, Dong Hee; Kim, Gui Nyun; Kim, Ji Eun; Kong, Dae Jung; Park, Hyangkyu; Son, Dohhee; Son, Dong-Chul; Kim, Jaeho; Kim, Jae Yool; Song, Sanghyeon; Choi, Suyong; Hong, Byung-Sik; Jo, Mihee; Kim, Hyunchul; Kim, Ji Hyun; Kim, Tae Jeong; Lee, Kyong Sei; Moon, Dong Ho; Park, Sung Keun; Rhee, Han-Bum; Seo, Eunsung; Shin, Seungsu; Sim, Kwang Souk; Choi, Minkyoo; Kang, Seokon; Kim, Hyunyong; Park, Chawon; Park, Inkyu; Park, Sangnam; Ryu, Geonmo; Choi, Young-Il; Choi, Young Kyu; Goh, Junghwan; Lee, Jongseok; Lee, Sungeun; Seo, Hyunkwan; Yu, Intae; Bilinskas, Mykolas Jurgis; Grigelionis, Ignas; Janulis, Mindaugas; Martisiute, Dalia; Petrov, Pavel; Sabonis, Tomas; Castilla Valdez, Heriberto; De La Cruz Burelo, Eduard; Lopez-Fernandez, Ricardo; Sánchez Hernández, Alberto; Villasenor-Cendejas, Luis Manuel; Carrillo Moreno, Salvador; Vazquez Valencia, Fabiola; Salazar Ibarguen, Humberto Antonio; Casimiro Linares, Edgar; Morelos Pineda, Antonio; Reyes-Santos, Marco A.; Allfrey, Philip; Krofcheck, David; Butler, Philip H.; Doesburg, Robert; Silverwood, Hamish; Ahmad, Muhammad; Ahmed, Ijaz; Asghar, Muhammad Irfan; Hoorani, Hafeez R.; Khan, Wajid Ali; Khurshid, Taimoor; Qazi, Shamona; Cwiok, Mikolaj; Dominik, Wojciech; Doroba, Krzysztof; Kalinowski, Artur; Konecki, Marcin; Krolikowski, Jan; Frueboes, Tomasz; Gokieli, Ryszard; Górski, Maciej; Kazana, Malgorzata; Nawrocki, Krzysztof; Romanowska-Rybinska, Katarzyna; Szleper, Michal; Wrochna, Grzegorz; Zalewski, Piotr; Almeida, Nuno; David Tinoco Mendes, Andre; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Sá Martins, Pedro; Musella, Pasquale; Nayak, Aruna; Ribeiro, Pedro Quinaz; Seixas, Joao; Silva, Pedro; Varela, Joao; Wöhri, Hermine Katharina; Belotelov, Ivan; Bunin, Pavel; Finger, Miroslav; Finger Jr., Michael; Golutvin, Igor; Kamenev, Alexey; Karjavin, Vladimir; Kozlov, Guennady; Lanev, Alexander; Moisenz, Petr; Palichik, Vladimir; Perelygin, Victor; Shmatov, Sergey; Smirnov, Vitaly; Volodko, Anton; Zarubin, Anatoli; Bondar, Nikolai; Golovtsov, Victor; Ivanov, Yury; Kim, Victor; Levchenko, Petr; Murzin, Victor; Oreshkin, Vadim; Smirnov, Igor; Sulimov, Valentin; Uvarov, Lev; Vavilov, Sergey; Vorobyev, Alexey; Andreev, Yuri; Gninenko, Sergei; Golubev, Nikolai; Kirsanov, Mikhail; Krasnikov, Nikolai; Matveev, Viktor; Pashenkov, Anatoli; Toropin, Alexander; Troitsky, Sergey; Epshteyn, Vladimir; Gavrilov, Vladimir; Kaftanov, Vitali; Kossov, Mikhail; Krokhotin, Andrey; Lychkovskaya, Natalia; Safronov, Grigory; Semenov, Sergey; Stolin, Viatcheslav; Vlasov, Evgueni; Zhokin, Alexander; Boos, Edouard; Dubinin, Mikhail; Dudko, Lev; Ershov, Alexander; Gribushin, Andrey; Kodolova, Olga; Lokhtin, Igor; Obraztsov, Stepan; Petrushanko, Sergey; Sarycheva, Ludmila; Savrin, Viktor; Snigirev, Alexander; Andreev, Vladimir; Azarkin, Maksim; Dremin, Igor; Kirakosyan, Martin; Rusakov, Sergey V.; Vinogradov, Alexey; Azhgirey, Igor; Bitioukov, Sergei; Grishin, Viatcheslav; Kachanov, Vassili; Konstantinov, Dmitri; Korablev, Andrey; Krychkine, Victor; Petrov, Vladimir; Ryutin, Roman; Slabospitsky, Sergey; Sobol, Andrei; Tourtchanovitch, Leonid; Troshin, Sergey; Tyurin, Nikolay; Uzunian, Andrey; Volkov, Alexey; Adzic, Petar; Djordjevic, Milos; Krpic, Dragomir; Milosevic, Jovan; Aguilar-Benitez, Manuel; Alcaraz Maestre, Juan; Arce, Pedro; Battilana, Carlo; Calvo, Enrique; Cepeda, Maria; Cerrada, Marcos; Colino, Nicanor; De La Cruz, Begona; Diez Pardos, Carmen; Domínguez Vázquez, Daniel; Fernandez Bedoya, Cristina; Fernández Ramos, Juan Pablo; Ferrando, Antonio; Flix, Jose; Fouz, Maria Cruz; Garcia-Abia, Pablo; Gonzalez Lopez, Oscar; Goy Lopez, Silvia; Hernandez, Jose M.; Josa, Maria Isabel; Merino, Gonzalo; Puerta Pelayo, Jesus; Redondo, Ignacio; Romero, Luciano; Santaolalla, Javier; Willmott, Carlos; Albajar, Carmen; Codispoti, Giuseppe; de Trocóniz, Jorge F; Cuevas, Javier; Fernandez Menendez, Javier; Folgueras, Santiago; Gonzalez Caballero, Isidro; Lloret Iglesias, Lara; Vizan Garcia, Jesus Manuel; Brochero Cifuentes, Javier Andres; Cabrillo, Iban Jose; Calderon, Alicia; Chamizo Llatas, Maria; Chuang, Shan-Huei; Duarte Campderros, Jordi; Felcini, Marta; Fernandez, Marcos; Gomez, Gervasio; Gonzalez Sanchez, Javier; Jorda, Clara; Lobelle Pardo, Patricia; Lopez Virto, Amparo; Marco, Jesus; Marco, Rafael; Martinez Rivero, Celso; Matorras, Francisco; Munoz Sanchez, Francisca Javiela; Piedra Gomez, Jonatan; Rodrigo, Teresa; Ruiz Jimeno, Alberto; Scodellaro, Luca; Sobron Sanudo, Mar; Vila, Ivan; Vilar Cortabitarte, Rocio; Abbaneo, Duccio; Auffray, Etiennette; Auzinger, Georg; Baillon, Paul; Ball, Austin; Barney, David; Bell, Alan James; Benedetti, Daniele; Bernet, Colin; Bialas, Wojciech; Bloch, Philippe; Bocci, Andrea; Bolognesi, Sara; Breuker, Horst; Brona, Grzegorz; Bunkowski, Karol; Camporesi, Tiziano; Cano, Eric; Cerminara, Gianluca; Christiansen, Tim; Coarasa Perez, Jose Antonio; Curé, Benoît; D'Enterria, David; De Roeck, Albert; Duarte Ramos, Fernando; Elliott-Peisert, Anna; Frisch, Benjamin; Funk, Wolfgang; Gaddi, Andrea; Gennai, Simone; Georgiou, Georgios; Gerwig, Hubert; Gigi, Dominique; Gill, Karl; Giordano, Domenico; Glege, Frank; Gomez-Reino Garrido, Robert; Gouzevitch, Maxime; Govoni, Pietro; Gowdy, Stephen; Guiducci, Luigi; Hansen, Magnus; Harvey, John; Hegeman, Jeroen; Hegner, Benedikt; Henderson, Conor; Hesketh, Gavin; Hoffmann, Hans Falk; Honma, Alan; Innocente, Vincenzo; Janot, Patrick; Karavakis, Edward; Lecoq, Paul; Leonidopoulos, Christos; Lourenco, Carlos; Macpherson, Alick; Maki, Tuula; Malgeri, Luca; Mannelli, Marcello; Masetti, Lorenzo; Meijers, Frans; Mersi, Stefano; Meschi, Emilio; Moser, Roland; Mozer, Matthias Ulrich; Mulders, Martijn; Nesvold, Erik; Nguyen, Matthew; Orimoto, Toyoko; Orsini, Luciano; Perez, Emmanuelle; Petrilli, Achille; Pfeiffer, Andreas; Pierini, Maurizio; Pimiä, Martti; Polese, Giovanni; Racz, Attila; Rolandi, Gigi; Rommerskirchen, Tanja; Rovelli, Chiara; Rovere, Marco; Sakulin, Hannes; Schäfer, Christoph; Schwick, Christoph; Segoni, Ilaria; Sharma, Archana; Siegrist, Patrice; Simon, Michal; Sphicas, Paraskevas; Spiga, Daniele; Spiropulu, Maria; Stöckli, Fabian; Stoye, Markus; Tropea, Paola; Tsirou, Andromachi; Tsyganov, Andrey; Veres, Gabor Istvan; Vichoudis, Paschalis; Voutilainen, Mikko; Zeuner, Wolfram Dietrich; Bertl, Willi; Deiters, Konrad; Erdmann, Wolfram; Gabathuler, Kurt; Horisberger, Roland; Ingram, Quentin; Kaestli, Hans-Christian; König, Stefan; Kotlinski, Danek; Langenegger, Urs; Meier, Frank; Renker, Dieter; Rohe, Tilman; Sibille, Jennifer; Starodumov, Andrei; Bortignon, Pierluigi; Caminada, Lea; Chen, Zhiling; Cittolin, Sergio; Dissertori, Günther; Dittmar, Michael; Eugster, Jürg; Freudenreich, Klaus; Grab, Christoph; Hervé, Alain; Hintz, Wieland; Lecomte, Pierre; Lustermann, Werner; Marchica, Carmelo; Martinez Ruiz del Arbol, Pablo; Meridiani, Paolo; Milenovic, Predrag; Moortgat, Filip; Nef, Pascal; Nessi-Tedaldi, Francesca; Pape, Luc; Pauss, Felicitas; Punz, Thomas; Rizzi, Andrea; Ronga, Frederic Jean; Rossini, Marco; Sala, Leonardo; Sanchez, Ann - Karin; Sawley, Marie-Christine; Stieger, Benjamin; Tauscher, Ludwig; Thea, Alessandro; Theofilatos, Konstantinos; Treille, Daniel; Urscheler, Christina; Wallny, Rainer; Weber, Matthias; Wehrli, Lukas; Weng, Joanna; Aguiló, Ernest; Amsler, Claude; Chiochia, Vincenzo; De Visscher, Simon; Favaro, Carlotta; Ivova Rikova, Mirena; Millan Mejias, Barbara; Regenfus, Christian; Robmann, Peter; Schmidt, Alexander; Snoek, Hella; Wilke, Lotte; Chang, Yuan-Hann; Chen, Kuan-Hsin; Chen, Wan-Ting; Dutta, Suchandra; Go, Apollo; Kuo, Chia-Ming; Li, Syue-Wei; Lin, Willis; Liu, Ming-Hsiung; Liu, Zong-Kai; Lu, Yun-Ju; Wu, Jing-Han; Yu, Shin-Shan; Bartalini, Paolo; Chang, Paoti; Chang, You-Hao; Chang, Yu-Wei; Chao, Yuan; Chen, Kai-Feng; Hou, George Wei-Shu; Hsiung, Yee; Kao, Kai-Yi; Lei, Yeong-Jyi; Lu, Rong-Shyang; Shiu, Jing-Ge; Tzeng, Yeng-Ming; Wang, Minzu; Adiguzel, Aytul; Bakirci, Mustafa Numan; Cerci, Salim; Dozen, Candan; Dumanoglu, Isa; Eskut, Eda; Girgis, Semiray; Gokbulut, Gul; Guler, Yalcin; Gurpinar, Emine; Hos, Ilknur; Kangal, Evrim Ersin; Karaman, Turker; Kayis Topaksu, Aysel; Nart, Alisah; Onengut, Gulsen; Ozdemir, Kadri; Ozturk, Sertac; Polatoz, Ayse; Sogut, Kenan; Tali, Bayram; Topakli, Huseyin; Uzun, Dilber; Vergili, Latife Nukhet; Vergili, Mehmet; Zorbilmez, Caglar; Akin, Ilina Vasileva; Aliev, Takhmasib; Bilmis, Selcuk; Deniz, Muhammed; Gamsizkan, Halil; Guler, Ali Murat; Ocalan, Kadir; Ozpineci, Altug; Serin, Meltem; Sever, Ramazan; Surat, Ugur Emrah; Yildirim, Eda; Zeyrek, Mehmet; Deliomeroglu, Mehmet; Demir, Durmus; Gülmez, Erhan; Halu, Arda; Isildak, Bora; Kaya, Mithat; Kaya, Ozlem; Ozkorucuklu, Suat; Sonmez, Nasuf; Levchuk, Leonid; Bell, Peter; Bostock, Francis; Brooke, James John; Cheng, Teh Lee; Clement, Emyr; Cussans, David; Frazier, Robert; Goldstein, Joel; Grimes, Mark; Hansen, Maria; Hartley, Dominic; Heath, Greg P.; Heath, Helen F.; Huckvale, Benedickt; Jackson, James; Kreczko, Lukasz; Metson, Simon; Newbold, Dave M.; Nirunpong, Kachanon; Poll, Anthony; Senkin, Sergey; Smith, Vincent J.; Ward, Simon; Basso, Lorenzo; Bell, Ken W.; Belyaev, Alexander; Brew, Christopher; Brown, Robert M.; Camanzi, Barbara; Cockerill, David J.A.; Coughlan, John A.; Harder, Kristian; Harper, Sam; Kennedy, Bruce W.; Olaiya, Emmanuel; Petyt, David; Radburn-Smith, Benjamin Charles; Shepherd-Themistocleous, Claire; Tomalin, Ian R.; Womersley, William John; Worm, Steven; Bainbridge, Robert; Ball, Gordon; Ballin, Jamie; Beuselinck, Raymond; Buchmuller, Oliver; Colling, David; Cripps, Nicholas; Cutajar, Michael; Davies, Gavin; Della Negra, Michel; Fulcher, Jonathan; Futyan, David; Guneratne Bryer, Arlo; Hall, Geoffrey; Hatherell, Zoe; Hays, Jonathan; Iles, Gregory; Karapostoli, Georgia; Lyons, Louis; Magnan, Anne-Marie; Marrouche, Jad; Nandi, Robin; Nash, Jordan; Nikitenko, Alexander; Papageorgiou, Anastasios; Pesaresi, Mark; Petridis, Konstantinos; Pioppi, Michele; Raymond, David Mark; Rompotis, Nikolaos; Rose, Andrew; Ryan, Matthew John; Seez, Christopher; Sharp, Peter; Sparrow, Alex; Tapper, Alexander; Tourneur, Stephane; Vazquez Acosta, Monica; Virdee, Tejinder; Wakefield, Stuart; Wardrope, David; Whyntie, Tom; Barrett, Matthew; Chadwick, Matthew; Cole, Joanne; Hobson, Peter R.; Khan, Akram; Kyberd, Paul; Leslie, Dawn; Martin, William; Reid, Ivan; Teodorescu, Liliana; Hatakeyama, Kenichi; Bose, Tulika; Carrera Jarrin, Edgar; Clough, Andrew; Fantasia, Cory; Heister, Arno; St. John, Jason; Lawson, Philip; Lazic, Dragoslav; Rohlf, James; Sperka, David; Sulak, Lawrence; Avetisyan, Aram; Bhattacharya, Saptaparna; Chou, John Paul; Cutts, David; Ferapontov, Alexey; Heintz, Ulrich; Jabeen, Shabnam; Kukartsev, Gennadiy; Landsberg, Greg; Narain, Meenakshi; Nguyen, Duong; Segala, Michael; Speer, Thomas; Tsang, Ka Vang; Borgia, Maria Assunta; Breedon, Richard; Calderon De La Barca Sanchez, Manuel; Cebra, Daniel; Chauhan, Sushil; Chertok, Maxwell; Conway, John; Cox, Peter Timothy; Dolen, James; Erbacher, Robin; Friis, Evan; Ko, Winston; Kopecky, Alexandra; Lander, Richard; Liu, Haidong; Maruyama, Sho; Miceli, Tia; Nikolic, Milan; Pellett, Dave; Robles, Jorge; Salur, Sevil; Schwarz, Thomas; Searle, Matthew; Smith, John; Squires, Michael; Tripathi, Mani; Vasquez Sierra, Ricardo; Veelken, Christian; Andreev, Valeri; Arisaka, Katsushi; Cline, David; Cousins, Robert; Deisher, Amanda; Duris, Joseph; Erhan, Samim; Farrell, Chris; Hauser, Jay; Ignatenko, Mikhail; Jarvis, Chad; Plager, Charles; Rakness, Gregory; Schlein, Peter; Tucker, Jordan; Valuev, Vyacheslav; Babb, John; Clare, Robert; Ellison, John Anthony; Gary, J William; Giordano, Ferdinando; Hanson, Gail; Jeng, Geng-Yuan; Kao, Shih-Chuan; Liu, Feng; Liu, Hongliang; Luthra, Arun; Nguyen, Harold; Pasztor, Gabriella; Satpathy, Asish; Shen, Benjamin C.; Stringer, Robert; Sturdy, Jared; Sumowidagdo, Suharyo; Wilken, Rachel; Wimpenny, Stephen; Andrews, Warren; Branson, James G.; Cerati, Giuseppe Benedetto; Dusinberre, Elizabeth; Evans, David; Golf, Frank; Holzner, André; Kelley, Ryan; Lebourgeois, Matthew; Letts, James; Mangano, Boris; Muelmenstaedt, Johannes; Padhi, Sanjay; Palmer, Christopher; Petrucciani, Giovanni; Pi, Haifeng; Pieri, Marco; Ranieri, Riccardo; Sani, Matteo; Sharma, Vivek; Simon, Sean; Tu, Yanjun; Vartak, Adish; Würthwein, Frank; Yagil, Avraham; Barge, Derek; Bellan, Riccardo; Campagnari, Claudio; D'Alfonso, Mariarosaria; Danielson, Thomas; Flowers, Kristen; Geffert, Paul; Incandela, Joe; Justus, Christopher; Kalavase, Puneeth; Koay, Sue Ann; Kovalskyi, Dmytro; Krutelyov, Vyacheslav; Lowette, Steven; Mccoll, Nickolas; Pavlunin, Viktor; Rebassoo, Finn; Ribnik, Jacob; Richman, Jeffrey; Rossin, Roberto; Stuart, David; To, Wing; Vlimant, Jean-Roch; Bornheim, Adolf; Bunn, Julian; Chen, Yi; Gataullin, Marat; Kcira, Dorian; Litvine, Vladimir; Ma, Yousi; Mott, Alexander; Newman, Harvey B.; Rogan, Christopher; Timciuc, Vladlen; Traczyk, Piotr; Veverka, Jan; Wilkinson, Richard; Yang, Yong; Zhu, Ren-Yuan; Akgun, Bora; Carroll, Ryan; Ferguson, Thomas; Iiyama, Yutaro; Jang, Dong Wook; Jun, Soon Yung; Liu, Yueh-Feng; Paulini, Manfred; Russ, James; Terentyev, Nikolay; Vogel, Helmut; Vorobiev, Igor; Cumalat, John Perry; Dinardo, Mauro Emanuele; Drell, Brian Robert; Edelmaier, Christopher; Ford, William T.; Heyburn, Bernadette; Luiggi Lopez, Eduardo; Nauenberg, Uriel; Smith, James; Stenson, Kevin; Ulmer, Keith; Wagner, Stephen Robert; Zang, Shi-Lei; Agostino, Lorenzo; Alexander, James; Chatterjee, Avishek; Das, Souvik; Eggert, Nicholas; Fields, Laura Johanna; Gibbons, Lawrence Kent; Heltsley, Brian; Hopkins, Walter; Khukhunaishvili, Aleko; Kreis, Benjamin; Kuznetsov, Valentin; Nicolas Kaufman, Gala; Patterson, Juliet Ritchie; Puigh, Darren; Riley, Daniel; Ryd, Anders; Shi, Xin; Sun, Werner; Teo, Wee Don; Thom, Julia; Thompson, Joshua; Vaughan, Jennifer; Weng, Yao; Winstrom, Lucas; Wittich, Peter; Biselli, Angela; Cirino, Guy; Winn, Dave; Abdullin, Salavat; Albrow, Michael; Anderson, Jacob; Apollinari, Giorgio; Atac, Muzaffer; Bakken, Jon Alan; Banerjee, Sunanda; Bauerdick, Lothar A.T.; Beretvas, Andrew; Berryhill, Jeffrey; Bhat, Pushpalatha C.; Bloch, Ingo; Borcherding, Frederick; Burkett, Kevin; Butler, Joel Nathan; Chetluru, Vasundhara; Cheung, Harry; Chlebana, Frank; Cihangir, Selcuk; Demarteau, Marcel; Eartly, David P.; Elvira, Victor Daniel; Esen, Selda; Fisk, Ian; Freeman, Jim; Gao, Yanyan; Gottschalk, Erik; Green, Dan; Gunthoti, Kranti; Gutsche, Oliver; Hahn, Alan; Hanlon, Jim; Harris, Robert M.; Hirschauer, James; Hooberman, Benjamin; James, Eric; Jensen, Hans; Johnson, Marvin; Joshi, Umesh; Khatiwada, Rakshya; Kilminster, Benjamin; Klima, Boaz; Kousouris, Konstantinos; Kunori, Shuichi; Kwan, Simon; Limon, Peter; Lipton, Ron; Lykken, Joseph; Maeshima, Kaori; Marraffino, John Michael; Mason, David; McBride, Patricia; McCauley, Thomas; Miao, Ting; Mishra, Kalanand; Mrenna, Stephen; Musienko, Yuri; Newman-Holmes, Catherine; O'Dell, Vivian; Popescu, Sorina; Pordes, Ruth; Prokofyev, Oleg; Saoulidou, Niki; Sexton-Kennedy, Elizabeth; Sharma, Seema; Soha, Aron; Spalding, William J.; Spiegel, Leonard; Tan, Ping; Taylor, Lucas; Tkaczyk, Slawek; Uplegger, Lorenzo; Vaandering, Eric Wayne; Vidal, Richard; Whitmore, Juliana; Wu, Weimin; Yang, Fan; Yumiceva, Francisco; Yun, Jae Chul; Acosta, Darin; Avery, Paul; Bourilkov, Dimitri; Chen, Mingshui; Di Giovanni, Gian Piero; Dobur, Didar; Drozdetskiy, Alexey; Field, Richard D.; Fisher, Matthew; Fu, Yu; Furic, Ivan-Kresimir; Gartner, Joseph; Goldberg, Sean; Kim, Bockjoo; Klimenko, Sergey; Konigsberg, Jacobo; Korytov, Andrey; Kropivnitskaya, Anna; Kypreos, Theodore; Matchev, Konstantin; Mitselmakher, Guenakh; Muniz, Lana; Pakhotin, Yuriy; Prescott, Craig; Remington, Ronald; Schmitt, Michael Houston; Scurlock, Bobby; Sellers, Paul; Skhirtladze, Nikoloz; Wang, Dayong; Yelton, John; Zakaria, Mohammed; Ceron, Cristobal; Gaultney, Vanessa; Kramer, Laird; Lebolo, Luis Miguel; Linn, Stephan; Markowitz, Pete; Martinez, German; Rodriguez, Jorge Luis; Adams, Todd; Askew, Andrew; Bandurin, Dmitry; Bochenek, Joseph; Chen, Jie; Diamond, Brendan; Gleyzer, Sergei V; Haas, Jeff; Hagopian, Sharon; Hagopian, Vasken; Jenkins, Merrill; Johnson, Kurtis F.; Prosper, Harrison; Sekmen, Sezen; Veeraraghavan, Venkatesh; Baarmand, Marc M.; Dorney, Brian; Guragain, Samir; Hohlmann, Marcus; Kalakhety, Himali; Ralich, Robert; Vodopiyanov, Igor; Adams, Mark Raymond; Anghel, Ioana Maria; Apanasevich, Leonard; Bai, Yuting; Bazterra, Victor Eduardo; Betts, Russell Richard; Callner, Jeremy; Cavanaugh, Richard; Dragoiu, Cosmin; Garcia-Solis, Edmundo Javier; Gerber, Cecilia Elena; Hofman, David Jonathan; Khalatyan, Samvel; Lacroix, Florent; O'Brien, Christine; Silvestre, Catherine; Smoron, Agata; Strom, Derek; Varelas, Nikos; Akgun, Ugur; Albayrak, Elif Asli; Bilki, Burak; Cankocak, Kerem; Clarida, Warren; Duru, Firdevs; Lae, Chung Khim; McCliment, Edward; Merlo, Jean-Pierre; Mermerkaya, Hamit; Mestvirishvili, Alexi; Moeller, Anthony; Nachtman, Jane; Newsom, Charles Ray; Norbeck, Edwin; Olson, Jonathan; Onel, Yasar; Ozok, Ferhat; Sen, Sercan; Wetzel, James; Yetkin, Taylan; Yi, Kai; Barnett, Bruce Arnold; Blumenfeld, Barry; Bonato, Alessio; Eskew, Christopher; Fehling, David; Giurgiu, Gavril; Gritsan, Andrei; Guo, Zijin; Hu, Guofan; Maksimovic, Petar; Rappoccio, Salvatore; Swartz, Morris; Tran, Nhan Viet; Whitbeck, Andrew; Baringer, Philip; Bean, Alice; Benelli, Gabriele; Grachov, Oleg; Murray, Michael; Noonan, Daniel; Radicci, Valeria; Sanders, Stephen; Wood, Jeffrey Scott; Zhukova, Victoria; Bolton, Tim; Chakaberia, Irakli; Ivanov, Andrew; Makouski, Mikhail; Maravin, Yurii; Shrestha, Shruti; Svintradze, Irakli; Wan, Zongru; Gronberg, Jeffrey; Lange, David; Wright, Douglas; Baden, Drew; Boutemeur, Madjid; Eno, Sarah Catherine; Ferencek, Dinko; Gomez, Jaime; Hadley, Nicholas John; Kellogg, Richard G.; Kirn, Malina; Lu, Ying; Mignerey, Alice; Rossato, Kenneth; Rumerio, Paolo; Santanastasio, Francesco; Skuja, Andris; Temple, Jeffrey; Tonjes, Marguerite; Tonwar, Suresh C.; Twedt, Elizabeth; Alver, Burak; Bauer, Gerry; Bendavid, Joshua; Busza, Wit; Butz, Erik; Cali, Ivan Amos; Chan, Matthew; Dutta, Valentina; Everaerts, Pieter; Gomez Ceballos, Guillelmo; Goncharov, Maxim; Hahn, Kristan Allan; Harris, Philip; Kim, Yongsun; Klute, Markus; Lee, Yen-Jie; Li, Wei; Loizides, Constantinos; Luckey, Paul David; Ma, Teng; Nahn, Steve; Paus, Christoph; Ralph, Duncan; Roland, Christof; Roland, Gunther; Rudolph, Matthew; Stephans, George; Sumorok, Konstanty; Sung, Kevin; Wenger, Edward Allen; Xie, Si; Yang, Mingming; Yilmaz, Yetkin; Yoon, Sungho; Zanetti, Marco; Cole, Perrie; Cooper, Seth; Cushman, Priscilla; Dahmes, Bryan; De Benedetti, Abraham; Dudero, Phillip Russell; Franzoni, Giovanni; Haupt, Jason; Klapoetke, Kevin; Kubota, Yuichi; Mans, Jeremy; Rekovic, Vladimir; Rusack, Roger; Sasseville, Michael; Singovsky, Alexander; Cremaldi, Lucien Marcus; Godang, Romulus; Kroeger, Rob; Perera, Lalith; Rahmat, Rahmat; Sanders, David A; Summers, Don; Bloom, Kenneth; Bose, Suvadeep; Butt, Jamila; Claes, Daniel R.; Dominguez, Aaron; Eads, Michael; Keller, Jason; Kelly, Tony; Kravchenko, Ilya; Lazo-Flores, Jose; Lundstedt, Carl; Malbouisson, Helena; Malik, Sudhir; Snow, Gregory R.; Baur, Ulrich; Godshalk, Andrew; Iashvili, Ia; Kharchilava, Avto; Kumar, Ashish; Shipkowski, Simon Peter; Smith, Kenneth; Alverson, George; Barberis, Emanuela; Baumgartel, Darin; Boeriu, Oana; Chasco, Matthew; Kaadze, Ketino; Reucroft, Steve; Swain, John; Wood, Darien; Zhang, Jinzhong; Anastassov, Anton; Kubik, Andrew; Odell, Nathaniel; Ofierzynski, Radoslaw Adrian; Pollack, Brian; Pozdnyakov, Andrey; Schmitt, Michael Henry; Stoynev, Stoyan; Velasco, Mayda; Won, Steven; Antonelli, Louis; Berry, Douglas; Hildreth, Michael; Jessop, Colin; Karmgard, Daniel John; Kolb, Jeff; Kolberg, Ted; Lannon, Kevin; Luo, Wuming; Lynch, Sean; Marinelli, Nancy; Morse, David Michael; Pearson, Tessa; Ruchti, Randy; Slaunwhite, Jason; Valls, Nil; Warchol, Jadwiga; Wayne, Mitchell; Ziegler, Jill; Bylsma, Ben; Durkin, Lloyd Stanley; Gu, Jianhui; Hill, Christopher; Killewald, Phillip; Kotov, Khristian; Ling, Ta-Yung; Rodenburg, Marissa; Williams, Grayson; Adam, Nadia; Berry, Edmund; Elmer, Peter; Gerbaudo, Davide; Halyo, Valerie; Hebda, Philip; Hunt, Adam; Jones, John; Laird, Edward; Lopes Pegna, David; Marlow, Daniel; Medvedeva, Tatiana; Mooney, Michael; Olsen, James; Piroué, Pierre; Quan, Xiaohang; Saka, Halil; Stickland, David; Tully, Christopher; Werner, Jeremy Scott; Zuranski, Andrzej; Acosta, Jhon Gabriel; Huang, Xing Tao; Lopez, Angel; Mendez, Hector; Oliveros, Sandra; Ramirez Vargas, Juan Eduardo; Zatserklyaniy, Andriy; Alagoz, Enver; Barnes, Virgil E.; Bolla, Gino; Borrello, Laura; Bortoletto, Daniela; Everett, Adam; Garfinkel, Arthur F.; Gecse, Zoltan; Gutay, Laszlo; Hu, Zhen; Jones, Matthew; Koybasi, Ozhan; Laasanen, Alvin T.; Leonardo, Nuno; Liu, Chang; Maroussov, Vassili; Merkel, Petra; Miller, David Harry; Neumeister, Norbert; Potamianos, Karolos; Shipsey, Ian; Silvers, David; Svyatkovskiy, Alexey; Yoo, Hwi Dong; Zablocki, Jakub; Zheng, Yu; Jindal, Pratima; Parashar, Neeti; Boulahouache, Chaouki; Cuplov, Vesna; Ecklund, Karl Matthew; Geurts, Frank J.M.; Liu, Jinghua H.; Morales, Jafet; Padley, Brian Paul; Redjimi, Radia; Roberts, Jay; Zabel, James; Betchart, Burton; Bodek, Arie; Chung, Yeon Sei; Covarelli, Roberto; de Barbaro, Pawel; Demina, Regina; Eshaq, Yossof; Flacher, Henning; Garcia-Bellido, Aran; Goldenzweig, Pablo; Gotra, Yury; Han, Jiyeon; Harel, Amnon; Miner, Daniel Carl; Orbaker, Douglas; Petrillo, Gianluca; Vishnevskiy, Dmitry; Zielinski, Marek; Bhatti, Anwar; Demortier, Luc; Goulianos, Konstantin; Lungu, Gheorghe; Mesropian, Christina; Yan, Ming; Atramentov, Oleksiy; Barker, Anthony; Duggan, Daniel; Gershtein, Yuri; Gray, Richard; Halkiadakis, Eva; Hidas, Dean; Hits, Dmitry; Lath, Amitabh; Panwalkar, Shruti; Patel, Rishi; Richards, Alan; Rose, Keith; Schnetzer, Steve; Somalwar, Sunil; Stone, Robert; Thomas, Scott; Cerizza, Giordano; Hollingsworth, Matthew; Spanier, Stefan; Yang, Zong-Chang; York, Andrew; Asaadi, Jonathan; Eusebi, Ricardo; Gilmore, Jason; Gurrola, Alfredo; Kamon, Teruki; Khotilovich, Vadim; Montalvo, Roy; Nguyen, Chi Nhan; Osipenkov, Ilya; Pivarski, James; Safonov, Alexei; Sengupta, Sinjini; Tatarinov, Aysen; Toback, David; Weinberger, Michael; Akchurin, Nural; Bardak, Cemile; Damgov, Jordan; Jeong, Chiyoung; Kovitanggoon, Kittikul; Lee, Sung Won; Mane, Poonam; Roh, Youn; Sill, Alan; Volobouev, Igor; Wigmans, Richard; Yazgan, Efe; Appelt, Eric; Brownson, Eric; Engh, Daniel; Florez, Carlos; Gabella, William; Johns, Willard; Kurt, Pelin; Maguire, Charles; Melo, Andrew; Sheldon, Paul; Velkovska, Julia; Arenton, Michael Wayne; Balazs, Michael; Boutle, Sarah; Buehler, Marc; Conetti, Sergio; Cox, Bradley; Francis, Brian; Hirosky, Robert; Ledovskoy, Alexander; Lin, Chuanzhe; Neu, Christopher; Yohay, Rachel; Gollapinni, Sowjanya; Harr, Robert; Karchin, Paul Edmund; Lamichhane, Pramod; Mattson, Mark; Milstène, Caroline; Sakharov, Alexandre; Anderson, Michael; Bachtis, Michail; Bellinger, James Nugent; Carlsmith, Duncan; Dasu, Sridhara; Efron, Jonathan; Gray, Lindsey; Grogg, Kira Suzanne; Grothe, Monika; Hall-Wilton, Richard; Herndon, Matthew; Klabbers, Pamela; Klukas, Jeffrey; Lanaro, Armando; Lazaridis, Christos; Leonard, Jessica; Lomidze, David; Loveless, Richard; Mohapatra, Ajit; Reeder, Don; Ross, Ian; Savin, Alexander; Smith, Wesley H.; Swanson, Joshua; Weinberg, Marc

    2011-01-01

    The Upsilon production cross section in proton-proton collisions at $\\sqrt{s}$ = 7 TeV is measured using a data sample collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 3.1 +/- 0.3 inverse picobarns. Integrated over the rapidity range |y|<2, we find the product of the Upsilon(1S) production cross section and branching fraction to dimuons to be sigma(pp to Upsilon(1S) X ) B(Upsilon(1S) to mu+ mu-) = 7.37 +/- 0.13^{+0.61}_{-0.42}pm 0.81 nb, where the first uncertainty is statistical, the second is systematic, and the third is associated with the estimation of the integrated luminosity of the data sample. This cross section is obtained assuming unpolarized Upsilon(1S) production. If the Upsilon(1S) production polarization is fully transverse or fully longitudinal the cross section changes by about 20%. We also report the measurement of the Upsilon(1S), Upsilon(2S), and Upsilon(3S) differential cross sections as a function of transverse momentum and rapidity.

  6. Cross section measurement of alpha particle induced nuclear reactions on natural cadmium up to 52 MeV

    OpenAIRE

    Ditrói, F.; Takács, S.; Haba, H.; Komori, Y.; Aikawa, M.

    2016-01-01

    Cross sections of alpha particle induced nuclear reactions have been measured on thin natural cadmium targets foils in the energy range from 11 to 51.2 MeV. This work was a part of our systematic study on excitation functions of light ion induced nuclear reactions on different target materials. Regarding the cross sections, the alpha induced reactions are not deeply enough investigated. Some of the produced isotopes are of medical interest, others have application in research and industry. Th...

  7. Display of cross sectional anatomy by nuclear magnetic resonance imaging

    International Nuclear Information System (INIS)

    Hinshaw, W.S.; Andrew, E.R.; Bottomley, P.A.; Holland, G.N.; Moore, W.S.; Worthington, B.S.

    1978-01-01

    High definition cross-sectional images produced by a new nuclear magnetic resonace (NMR) technique are shown. The images are a series of thin section scans in the coronal plane of the head of a rabbit. The NMR images are derived from the distribution of the density of mobile hydrogen atoms. Various tissue types can be distinguished and a clear registration of gross anatomy is demonstrated. No known hazards are associated with the technique. (author)

  8. Display of cross sectional anatomy by nuclear magnetic resonance imaging.

    Science.gov (United States)

    Hinshaw, W S; Andrew, E R; Bottomley, P A; Holland, G N; Moore, W S

    1978-04-01

    High definition cross-sectional images produced by a new nuclear magnetic resonance (NMR) technique are shown. The images are a series of thin section scans in the coronal plane of the head of a rabbit. The NMR images are derived from the distribution of the density of mobile hydrogen atoms. Various tissue types can be distinguished and a clear registration of gross anatomy is demonstrated. No known hazards are associated with the technique.

  9. Thermal Neutron Capture Cross Sections of the PalladiumIsotopes

    Energy Technology Data Exchange (ETDEWEB)

    Firestone, R.B.; Krticka, M.; McNabb, D.P.; Sleaford, B.; Agvaanluvsan, U.; Belgya, T.; Revay, Zs.

    2006-07-17

    Precise gamma-ray thermal neutron capture cross sectionshave been measured at the Budapest Reactor for all elements withZ=1-83,92 except for He and Pm. These measurements and additional datafrom the literature been compiled to generate the Evaluated Gamma-rayActivation File (EGAF), which is disseminated by LBNL and the IAEA. Thesedata are nearly complete for most isotopes with Z<20 so the totalradiative thermal neutron capture cross sections can be determineddirectly from the decay scheme. For light isotopes agreement with therecommended values is generally satisfactory although large discrepanciesexist for 11B, 12,13C, 15N, 28,30Si, 34S, 37Cl, and 40,41K. Neutroncapture decay data for heavier isotopes are typically incomplete due tothe contribution of unresolved continuum transitions so only partialradiative thermal neutron capture cross sections can be determined. Thecontribution of the continuum to theneutron capture decay scheme arisesfrom a large number of unresolved levels and transitions and can becalculated by assuming that the fluctuations in level densities andtransition probabilities are statistical. We have calculated thecontinuum contribution to neutron capture decay for the palladiumisotopes with the Monte Carlo code DICEBOX. These calculations werenormalized to the experimental cross sections deexciting low excitationlevels to determine the total radiative thermal neutron capture crosssection. The resulting palladium cross sections values were determinedwith a precision comparable to the recommended values even when only onegamma-ray cross section was measured. The calculated and experimentallevel feedings could also be compared to determine spin and parityassignments for low-lying levels.

  10. α-induced reaction cross sections in the mass range A ≈ 20 ‑ 50: a critical review

    Science.gov (United States)

    Mohr, Peter

    2018-01-01

    In a recent review it was shown that the cross sections of α-induced reactions in the A ≈ 20 ‑ 50 mass range follow a general and smooth trend in most cases. For comparison of cross sections of different targets at various energies the method of reduced cross sections σ red and reduced energies E red was used. Four outliers were identified: 36Ar and 40Ar with unusal small cross sections and 23Na and 33S with unusual huge cross sections. New data for 23Na were presented at this NPA-7 conference; contrary to the previous data, these new data fit into the general systematics. In addition, a relation between the most effective energy E 0 for astrophysical reaction rates (the so-called Gamow window) and the reduced energy E red is presented.

  11. Absolute measurements of chlorine Cl+ cation single photoionization cross section

    NARCIS (Netherlands)

    Hernandez, E. M.; Juarez, A. M.; Kilcoyne, A. L. D.; Aguilar, A.; Hernandez, L.; Antillon, A.; Macaluso, D.; Morales-Mori, A.; Gonzalez-Magana, O.; Hanstorp, D.; Covington, A. M.; Davis, V.; Calabrese, D.; Hinojosa, G.

    The photoionization of Cl+ leading to Cl2+ was measured in the photon energy range of 19.5-28.0 eV. A spectrum with a photon energy resolution of 15 meV normalized to absolute cross-section measurements is presented. The measurements were carried out by merging a Cl+ ion beam with a photon beam of

  12. Proton-Helium Elastic Electromagnetic Cross-Section

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Burn [Chinese Academy of Sciences (CAS), Lanzhou (China); Ng, Kingyuen B. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2015-11-01

    In the test facility of the C-ADS project, A 25-MeV proton beam is directed to hit a target consisting of 1-mm tungsten balls lubricated by 100-Pa helium gas. To estimate the power loss to the helium gas, an accurate collision cross section is computed.

  13. Cross section for inelastic neutron acceleration by 178Hfm2

    International Nuclear Information System (INIS)

    Karamyan, S.A.; Carroll, J.J.

    2009-01-01

    The scattering of thermal neutrons from isomeric nuclei may include events in which the outgoing neutrons have increased kinetic energy. This process has been called Inelastic Neutron Acceleration (INNA) and occurs when the final nucleus after emission of the neutron is left in a state with lower energy than that of the isomer. The result, therefore, is an induced depletion of the isomeric population to the ground state. A cascade of several gammas must accompany the neutron emission to release the high angular momentum of the initial isomeric state. INNA was previously observed in a few cases and the associated cross sections were only in modest agreement with theoretical estimates. The most recent measurement of an INNA cross section was σ INNA = (258 ± 58) b for neutron scattering by 177 Lu m . In the present work, an INNA cross section of σ INNA = 152 -36 +51 b was deduced from measurements of the total burn-up of the high-spin, four-quasiparticle isomer 178 Hf m2 during irradiation by thermal neutrons. Statistical estimates for the probability of different reaction channels past neutron absorption were used in the analysis, and the deduced σ INNA is compared to the theoretically predicted cross section

  14. Predictions of diffractive cross sections in proton-proton collisions

    Energy Technology Data Exchange (ETDEWEB)

    Goulianos, Konstantin [Rockefeller University, 1230 York Avenue, New York, NY 10065 (United States)

    2013-04-15

    We review our pre-LHC predictions of the total, elastic, total-inelastic, and diffractive components of proton-proton cross sections at high energies, expressed in the form of unitarized expressions based on a special parton-model approach to diffraction employing inclusive proton parton distribution functions and QCD color factors and compare with recent LHC results.

  15. Photon - axion conversion cross sections in an electromagnetic field

    International Nuclear Information System (INIS)

    Dang Van Soa; Ha Huy Bang

    1999-12-01

    Photon - axion conversions in static magnetic fields and in a periodic field with frequency equal to the axion mass are reconsidered in detail by Feynman methods. The differential cross sections are presented and numerical evaluations are given. It is shown that there is a resonant conversion for the considered process. Some estimates for experiments are given from our results. (author)

  16. XCOM: Photon cross sections on a personal computer

    International Nuclear Information System (INIS)

    Berger, M.J.; Hubbell, J.H.

    1987-07-01

    A computer program and data base are presented which can be used to calculate, with a personal computer, photon cross sections for scattering, photoelectric absorption and pair production, as well as total attenuation coefficients, in any element, compound or mixture, at energies from 1 keV to 100 GeV

  17. Generation of neutron scattering cross sections for silicon dioxide

    International Nuclear Information System (INIS)

    Ramos, R; Marquez Damian, J.I; Granada, J.R.; Cantargi, F

    2009-01-01

    A set of neutron scattering cross sections for silicon and oxygen bound in silicon dioxide were generated and validated. The cross sections were generated in the ACE format for MCNP using the nuclear data processing system NJOY, and the validation was done with published experimental data. This cross section library was applied to the calculation of five critical configurations published in the benchmark Critical Experiments with Heterogeneous Compositions of Highly Enriched Uranium, Silicon Dioxide and Polyethylene. The original calculations did not use the thermal scattering libraries generated in this work and presented significant differences with the experimental results. For this reason, the newly generated library was added to the input and the multiplication factor for each configuration was recomputed. The utilization of the thermal scattering libraries did not result in an improvement of the computational results. Based on this we conclude that integral experiments to validate this type of thermal cross sections need to be designed with a higher influence of thermal scattering in the measured result, and the experiments have to be performed under more controlled conditions. [es

  18. A New Measurement of Neutron Induced Fission Cross Sections

    Science.gov (United States)

    Magee, Joshua; Niffte Collaboration

    2017-09-01

    Neutron induced fission cross sections of actinides are of great interest in nuclear energy and stockpile stewardship. Traditionally, measurements of these cross sections have been made with fission chambers, which provide limited information on the actual fragments, and ultimately result in uncertainties on the order of several percent. The Neutron Induced Fission ragment Tracking Experiment (NIFFTE) collaboration designed and built a fission Time Projection Chamber (fissionTPC), which provides additional information on these processes, through 3-dimensional tracking, improved particle identification, and in-situ profiles of target and beam non-uniformities. Ultimately, this should provide sub-percent measurements of (n,f) cross-sections. During the 2016 run cycle, measurements of the 238U(n,f)/235U(n,f) cross section shape was performed at the Los Alamos Neutron Science Center (LANSCE) Weapons Neutron Research (WNR) facility. An overview of the fission TPC will be given, as well as these recently reported results. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  19. Scattering and absorption differential cross sections for double ...

    Indian Academy of Sciences (India)

    The scattering and absorption differential cross sections for nonlinear QED process such as double photon Compton scattering have been measured as a function of independent final photon energy. The incident gamma photons are of 0.662 MeV in energy as produced by an 8 Ci137Cs radioactive source and thin ...

  20. A cross-sectional survey on the lifestyle and healthseeking ...

    African Journals Online (AJOL)

    Objectives: The objectives of the study were to determine the level of practice of a healthy lifestyle, to assess the health education provided to patients with diabetes and to determine the prevalence of obesity among Basotho patients with diabetes. Design: A cross-sectional study enrolled 192 patients between November ...

  1. Measurement, calculation and evaluation of photon production cross-sections

    International Nuclear Information System (INIS)

    Kocherov, N.P.

    1990-11-01

    The meeting proceedings were divided into three sessions devoted to the following topics: Experimental measurement and techniques (3 papers), calculation of photon cross-sections (9 papers), and evaluation (2 papers). A separate abstract was prepared for each of these papers. Refs, figs and tabs

  2. Electron Impact Ionization Cross Sections of Gold, Chromium and Iron

    Science.gov (United States)

    1976-01-01

    daca ...................... 30 4. Repeatable hysteresis example ...................... 31 4 5. Unstable Au cross section data...The nature of the investigation requires evaporation of the experimental material in order to create an atomic beam. Some of the beam, of necessity ...unstable or otherwise malfunctioning. The investigation was further complicated and delayed by the necessity of movirng the entire experi- ment

  3. Cross-sectional study of health effects of cryolite production

    DEFF Research Database (Denmark)

    Friis, Henrik; Clausen, J; Gyntelberg, F

    1989-01-01

    A cross-sectional health study of 101 cryolite workers was performed, using spirometry and a questionnaire. Multiple regression analysis revealed a significant correlation between the index of smoking and a decrease in FEV1 (per cent). There was no significant correlation between work...... in relation to work, compared to 3.8 per cent of 1752 men participating in the Copenhagen Male Study....

  4. Electron Impact Multiple Ionization Cross Sections for Solar Physics

    Science.gov (United States)

    Hahn, M.; Savin, D. W.; Mueller, A.

    2017-12-01

    We have compiled a set of electron-impact multiple ionization (EIMI) cross sections for astrophysically relevant ions. EIMI can have a significant effect on the ionization balance of non-equilibrium plasmas. For example, it can be important if there is a rapid change in the electron temperature, as in solar flares or in nanoflare coronal heating. EIMI is also likely to be significant when the electron energy distribution is non-thermal, such as if the electrons follow a kappa distribution. Cross sections for EIMI are needed in order to account for these processes in plasma modeling and for spectroscopic interpretation. Here, we describe our comparison of proposed semiempirical formulae to the available experimental EIMI cross section data. Based on this comparison, we have interpolated and extrapolated fitting parameters to systems that have not yet been measured. A tabulation of the fit parameters is provided for thousands of EIMI cross sections. We also highlight some outstanding issues that remain to be resolved.

  5. Cross-sectional dependence in panel data analysis

    NARCIS (Netherlands)

    Sarafidis, V.; Wansbeek, T.J.

    2012-01-01

    This article provides an overview of the existing literature on panel data models with error cross-sectional dependence (CSD). We distinguish between weak and strong CSD and link these concepts to the spatial and factor structure approaches. We consider estimation under strong and weak exogeneity of

  6. Evaluated activation cross-sections and intercomparison of the ...

    Indian Academy of Sciences (India)

    For all isotopes and incident particles, the same methodology is applied to obtain the cross-section ... data library with mutually consistent reactions and covariance information for all isotopes. [24]. 2.3 EMPIRE ..... Medical Applications Statistical Theory of Nuclear Reactions, 30 September–4 October, 2013. [38] H Feshbach ...

  7. Measurement of MA fission cross sections at YAYOI

    Energy Technology Data Exchange (ETDEWEB)

    Ohkawachi, Yasushi; Ohki, Shigeo; Wakabayashi, Toshio [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-03-01

    Fission cross section ratios of minor actinide nuclides (Am-241, Am-243) relative to U-235 in the fast neutron energy region have been measured using a back-to-back (BTB) fission chamber at YAYOI fast neutron source reactor. A small BTB fission chamber was developed to measure the fission cross section ratios in the center of the core at YAYOI reactor. Dependence of the fission cross section ratios on neutron spectra was investigated by changing the position of the detector in the reactor core. The measurement results were compared with the fission cross sections in the JENDL-3.2, ENDF/B-VI and JEF-2.2 libraries. It was found that calculated values of Am-241 using the JENDL-3.2, ENDF/B-VI and JEF-2.2 data are lower by about 15% than the measured value in the center of the core (the neutron average energy is 1.44E+6(eV)). And, good agreement can be seen the measured value and calculated value of Am-243 using the JENDL-3.2 data in the center of the core (the neutron average energy is 1.44E+6)(eV), but calculated values of Am-243 using the ENDF/B-VI and JEF-2.2 data are lower by 11% and 13% than the measured value. (author)

  8. Radar cross sections for mesospheric echoes at Jicamarca

    Directory of Open Access Journals (Sweden)

    G. A. Lehmacher

    2009-07-01

    Full Text Available Radar cross sections (RCS of mesospheric layers at 50 MHz observed at Jicamarca, Peru, range from 10−18 to 10−16 m−1, three orders of magnitudes smaller than cross sections reported for polar mesospheric winter echoes during solar proton events and six orders of magnitude smaller than polar mesospheric summer echoes. Large RCS are found in thick layers around 70 km that also show wide radar spectra, which is interpreted as turbulent broadening. For typical atmospheric and ionospheric conditions, volume scattering RCS for stationary, homogeneous, isotropic turbulence at 3 m are also in the range 10−18 to 10−16 m−1, in reasonable agreement with measurements. Moreover, theory predicts maximum cross sections around 70 km, also in agreement with observations. Theoretical values are still a matter of order-of-magnitude estimation, since the Bragg scale of 3 m is near or inside the viscous subrange, where the form of the turbulence spectrum is not well known. In addition, steep electron density gradients can increase cross-sections significantly. For thin layers with large RCS and narrow spectra, isotropic turbulence theory fails and scattering or reflection from anisotropic irregularities may gain relevance.

  9. Neutrino cross-section in ultrahigh energy regime using double ...

    Indian Academy of Sciences (India)

    Kalpana Bora

    2017-10-05

    Oct 5, 2017 ... Abstract. Studies on neutrino–nucleon (νN) cross-sections have regained interest due to increasing importance of precision measurements, as they are needed as an ingredient in all neutrino experiments. In this work, we use the QCD-inspired double asymptotic limit fit of electron–proton structure function ...

  10. Plots of the experimental and evaluated photoneutron cross-sections

    International Nuclear Information System (INIS)

    Blokhin, A.I.; Nasyrova, S.M.

    1991-08-01

    Graphical plots of experimental data of photon induced nuclear reaction cross-sections are given for many elements and isotopes. The numerical data were taken from the international EXFOR data library which is available from the nuclear data centers. For selected nuclides evaluated data have been included in the plots. (author). Refs, 3 tabs

  11. Scattering and absorption differential cross sections for double ...

    Indian Academy of Sciences (India)

    absorption differential cross sections agree with theory within experimental estimated error. Keywords. ... have been given in a previous paper [2] to which we refer for literature on the theoretical studies on this process ... thick iron and 1 mm thick aluminium, with iron facing lead to absorb K x-rays emitted by lead shielding.

  12. Health Problems Among the Elderly: A Cross.Sectional Study ...

    African Journals Online (AJOL)

    Aims: To identify the geriatric health problems in samples drawn from a slum and a village, and also to explore any gender and urban.rural difference morbidity. Subject and. Methods: A community.based cross.sectional study was carried out by house to house survey of all people aged over 60 years in an urban slum and a ...

  13. Positron total scattering cross-sections for alkali atoms

    Science.gov (United States)

    Sinha, Nidhi; Singh, Suvam; Antony, Bobby

    2018-01-01

    Positron-impact total scattering cross-sections for Li, Na, K, Rb, Cs and Fr atoms are calculated in the energy range from 5-5000 eV employing modified spherical complex optical potential formalism. The main aim of this work is to apply this formalism to the less studied positron-target collision systems. The results are compared with previous theoretical and experimental data, wherever available. In general, the present data show overall agreement and consistency with other results. Furthermore, we have done a comparative study of the results to investigate the effect of atomic size on the cross-sections as we descend through the group in the periodic table. We have also plotted a correlation graph of the present total cross-sections with polarizability and number of target electrons. The two correlation plots confirm the credibility and consistency of the present results. Besides, this is the first theoretical attempt to report positron-impact total cross-sections of alkali atoms over such a wide energy range.

  14. Comparing Ranque tubes of circular and square cross section

    Directory of Open Access Journals (Sweden)

    Kabardin Ivan K.

    2017-01-01

    Full Text Available The efficiency of temperature end energy separation is compared for Ranque tubes of circular and square cross section, with the square side equal to the circle diameter. The “square” tube demonstrates approximately two times less efficiency, yet the separation effect still being evidently presented.

  15. Electron impact ionisation cross sections of iron oxides

    Science.gov (United States)

    Huber, Stefan E.; Mauracher, Andreas; Sukuba, Ivan; Urban, Jan; Maihom, Thana; Probst, Michael

    2017-12-01

    We report electron impact ionisation cross sections (EICSs) of iron oxide molecules, FexOx and FexOx+1 with x = 1, 2, 3, from the ionisation threshold to 10 keV, obtained with the Deutsch-Märk (DM) and binary-encounter-Bethe (BEB) methods. The maxima of the EICSs range from 3.10 to 9 . 96 × 10-16 cm2 located at 59-72 eV and 5.06 to 14.32 × 10-16 cm2 located at 85-108 eV for the DM and BEB approaches, respectively. The orbital and kinetic energies required for the BEB method are obtained by employing effective core potentials for the inner core electrons in the quantum chemical calculations. The BEB cross sections are 1.4-1.7 times larger than the DM cross sections which can be related to the decreasing population of the Fe 4s orbitals upon addition of oxygen atoms, together with the different methodological foundations of the two methods. Both the DM and BEB cross sections can be fitted excellently to a simple analytical expression used in modelling and simulation codes employed in the framework of nuclear fusion research. Supplementary material in the form of one pdf file available from the Journal web page at http://https://doi.org/10.1140/epjd/e2017-80308-2.

  16. Charm photoproduction cross section at 20GeV

    International Nuclear Information System (INIS)

    Abe, K.; Bacon, T.C.; Ballam, J.

    1983-05-01

    Forty seven charm events have been observed in an exposure of the SLAC Hybrid Facility to a 20 GeV backward scattered laser beam. Thirty seven events survive all the necessary cuts imposed. Based on this number the total charm cross section is calculated to be (63 +33 sub(-28))nb. (author)

  17. Neutron elastic and inelastic cross section measurements for 28Si

    Science.gov (United States)

    Derdeyn, E. C.; Lyons, E. M.; Morin, T.; Hicks, S. F.; Vanhoy, J. R.; Peters, E. E.; Ramirez, A. P. D.; McEllistrem, M. T.; Mukhopadhyay, S.; Yates, S. W.

    2017-09-01

    Neutron elastic and inelastic cross sections are critical for design and implementation of nuclear reactors and reactor equipment. Silicon, an element used abundantly in fuel pellets as well as building materials, has little to no experimental cross sections in the fast neutron region to support current theoretical evaluations, and thus would benefit from any contribution. Measurements of neutron elastic and inelastic differential scattering cross sections for 28Si were performed at the University of Kentucky Accelerator Laboratory for incident neutron energies of 6.1 MeV and 7.0 MeV. Neutrons were produced by accelerated deuterons incident on a deuterium gas cell. These nearly mono-energetic neutrons then scattered off a natural Si sample and were detected using liquid deuterated benzene scintillation detectors. Scattered neutron energy was deduced using time-of-flight techniques in tandem with kinematic calculations for an angular distribution. The relative detector efficiency was experimentally determined over a neutron energy range from approximately 0.5 to 7.75 MeV prior to the experiment. Yields were corrected for multiple scattering and neutron attenuation in the sample using the forced-collision Monte Carlo correction code MULCAT. Resulting cross sections will be presented along with comparisons to various data evaluations. Research is supported by USDOE-NNSA-SSAP: NA0002931, NSF: PHY-1606890, and the Donald A. Cowan Physics Institute at the University of Dallas.

  18. Event history analysis and the cross-section

    DEFF Research Database (Denmark)

    Keiding, Niels

    2006-01-01

    Examples are given of problems in event history analysis, where several time origins (generating calendar time, age, disease duration, time on study, etc.) are considered simultaneously. The focus is on complex sampling patterns generated around a cross-section. A basic tool is the Lexis diagram....

  19. Evaluation of the neutron cross sections for Pu-240

    International Nuclear Information System (INIS)

    Weston, L.W.; Arthur, E.D.

    1987-04-01

    The present evaluation is proposed to supersede the ENDF/B-V, Revision 2 file for 240 Pu. In this work, resonance parameters, cross sections, energy distributions, and angular distributions have been modified. These changes are outlined in detail and appropriate references included. 37 refs., 21 figs., 2 tabs

  20. Measurement of neutron capture cross sections of Tc-99

    International Nuclear Information System (INIS)

    Igashira, Masayuki

    2000-02-01

    For studies on nuclear transmutation of long-lived fission products(LLFPs) in a fast reactor, detailed characteristics of reactor core such as transmutation performance have to be investigated, so accurate neutron cross section data of LLFPs become necessary. Therefore, the keV-neutron capture cross sections of Tc-99, which is one of important LLFPs, were measured in the present study to obtain the accurate data. The measurement was relative to the standard capture cross sections of Au-197. A neutron time-of-flight method was adopted with a ns-pulsed neutron source by a Pelletron accelerator and a large anti-Compton Nal(Tl) gamma-ray detector. As a result, the capture cross sections of Tc-99 were obtained with the error of about 5% in the incident neutron energy region of 10 to 600 keV. The present data were compared with other experimental data and the evaluated values of JENDL-3.2, and it was found that the evaluations of JENDL-3.2 were 15-20% smaller than the present measurements. (author)

  1. The measurement of neutron scattering cross sections at small angles

    International Nuclear Information System (INIS)

    Qi, H.Q.; Liu, Y.C.; Chen, Z.P.; Wu, X.C.; Wang, W.H.; Zhang, J.

    1985-08-01

    A position sensitive neutron detector was used to measure the scattering cross sections of 14.7 MeV neutrons from Pb between 3 0 and 9 0 . The method to correct the effects of finite positional resolution by unfolding positional spectrum was studied. (author)

  2. Cross sectional evaluation of awareness of prevention of dental ...

    African Journals Online (AJOL)

    Cross sectional evaluation of awareness of prevention of dental caries among general paediatricians in Ghaziabad district, India. ... Pre‑tested, structured and self administered questionnaire was used in the survey and data analysis was done by using 'SPSS' software version 16.0 (IBM, United States). Results: Our study ...

  3. C+C Fusion Cross Sections Measurements for Nuclear Astrophysics

    International Nuclear Information System (INIS)

    Almaraz-Calderon, S.; Carnelli, P. F. F.; Rehm, K. E.; Albers, M.; Alcorta, M.; Bertone, P. F.; Digiovine, B.; Esbensen, H.; Fernandez Niello, J. O.; Jiang, C. L.; Lai, J.; Nusair, O.; Palchan-Hazan, T.; Pardo, R. C.; Paul, M.; Giardina, G.; Eidelman, S.; Venanzoni, G.; Battaglieri, M.; Mandaglio, G.

    2015-01-01

    Total fusion cross section of carbon isotopes were obtained using the newly developed MUSIC detector. MUSIC is a highly efficient, active target-detector system designed to measure fusion excitation functions with radioactive beams. The present measurements are relevant for understanding x-ray superbursts. The results of the first MUSIC campaign as well as the astrophysical implications are presented in this work

  4. Measured and evaluated fast neutron cross sections of elemental nickel

    International Nuclear Information System (INIS)

    Guenther, P.; Smith, A.; Smith, D.; Whalen, J.; Howerton, R.

    1975-07-01

    Fast neutron total and scattering cross sections of elemental nickel are measured. Differential elastic scattering cross sections are determined from incident energies of 0.3 to 4.0 MeV. The cross sections for the inelastic neutron excitation of states at: 1.156 +- 0.015, 1.324 +- 0.015, 1.443 +- 0.015, 2.136 +- 0.013, 2.255 +- 0.030, 2.449 +- 0.030, 2.614 +- 0.020 and 2.791 +- 0.025 MeV are measured to incident neutron energies of 4.0 MeV. The total neutron cross sections are determined from 0.25 to 5.0 MeV. The experimental results are discussed in the context of optical and statistical models. It is shown that resonance width-fluctuation and correlation effects are significant. The present experimental and theoretical results, together with previously reported values, are used to construct a comprehensive evaluated elemental data file in the ENDF format. Some comparisons are made with previously reported evaluated files. In addition, some selected reactions which are widely used in dosimetry and other applications are presented as supplemental evaluated isotopic-data files. The numerical quantities are presented in tabular form. (3 tables, 29 figures)

  5. Cross sectional survey of mange in traditional goats in Gwembe ...

    African Journals Online (AJOL)

    A cross-sectional study was conducted from December 2013 to March 2014 in all the nine veterinary camps in Gwembe district, Zambia in order to evaluate goat keepers‟ knowledge, attitude and practices in relation to mange using a structured questionnaire and to determine its prevalence in animals through clinical ...

  6. Capital yields assessment trough cross section production function

    Czech Academy of Sciences Publication Activity Database

    Kodera, Jan; Pánková, V.

    2001-01-01

    Roč. 8, č. 14 (2001), s. 79-87 ISSN 1212-074X R&D Projects: GA ČR GA402/00/0439 Institutional research plan: AV0Z1075907 Keywords : yield of capital * cross-section production function * maximisation of profit Subject RIV: AH - Economics

  7. Motorcycle-Related Trauma in South Sudan: a cross sectional ...

    African Journals Online (AJOL)

    Motorcycle-Related Trauma in South Sudan: a cross sectional observational study. Andrew Allan. Abstract. Motorcycle related trauma is a major cause of morbidity in those of working age in the developing world. One hundred and sixteen patients involved in motorcycle related accidents were identified over four weeks at ...

  8. On the treatment of resonance cross sections in thermal reactor ...

    African Journals Online (AJOL)

    This paper discusses the mathematical models and methods used for calculating resonance cross sections in the resonance region of the neutron energy spectrum. Particular attention has been paid to the treatment outlined in the WIMSD/4 version of the WIMS lattice transport code. The significance of the resonance ...

  9. Reference Cross Sections for Charged-particle Monitor Reactions

    Science.gov (United States)

    Hermanne, A.; Ignatyuk, A. V.; Capote, R.; Carlson, B. V.; Engle, J. W.; Kellett, M. A.; Kibédi, T.; Kim, G.; Kondev, F. G.; Hussain, M.; Lebeda, O.; Luca, A.; Nagai, Y.; Naik, H.; Nichols, A. L.; Nortier, F. M.; Suryanarayana, S. V.; Takács, S.; Tárkányi, F. T.; Verpelli, M.

    2018-02-01

    Evaluated cross sections of beam-monitor reactions are expected to become the de-facto standard for cross-section measurements that are performed over a very broad energy range in accelerators in order to produce particular radionuclides for industrial and medical applications. The requirements for such data need to be addressed in a timely manner, and therefore an IAEA coordinated research project was launched in December 2012 to establish or improve the nuclear data required to characterise charged-particle monitor reactions. An international team was assembled to recommend more accurate cross-section data over a wide range of targets and projectiles, undertaken in conjunction with a limited number of measurements and more extensive evaluations of the decay data of specific radionuclides. Least-square evaluations of monitor-reaction cross sections including uncertainty quantification have been undertaken for charged-particle beams of protons, deuterons, 3He- and 4He-particles. Recommended beam monitor reaction data with their uncertainties are available at the IAEA-NDS medical portal http://www-nds.iaea.org/medical/monitor_reactions.html.

  10. Measurement of photoexcitation cross-sections of uranium by ...

    Indian Academy of Sciences (India)

    Abstract. We report the measurement of photoexcitation cross-sections of three first- step uranium transitions (0 → 16900.38 cm−1, 0 → 17361.89 cm−1 and 620 → 17361.89 cm−1) using saturation method. These measurements were performed on a resonance ionization mass spectrometry (RIMS) set-up consisting of ...

  11. Measurement of photoexcitation cross-sections of uranium by ...

    Indian Academy of Sciences (India)

    We report the measurement of photoexcitation cross-sections of three first-step uranium transitions (0 → 16900.38 cm-1 , 0 → 17361.89 cm-1 and 620 → 17361.89 cm-1) using saturation method. These measurements were performed on a resonance ionization mass spectrometry (RIMS) set-up consisting of ...

  12. Experimental determination of vibrational cross sections for diatomic molecules

    International Nuclear Information System (INIS)

    Noqueira, J.C.; Iga, I.; Lee Mu Tao; Lopes, M.C.A.; Almeida, D.P. de

    1988-01-01

    To obtain inelastic differential cross sections from electronic and vibrational molecular excitations by electron impact, it was constructed a new spectrometer to operate in the energy range from 100 to 500 eV. The deceleration lenses as well as the analyser were tested for nitrogen molecule and 350 eV electrons. (A.C.A.S.) [pt

  13. A Cross-Sectional Study on Knowledge and Perceptions of ...

    African Journals Online (AJOL)

    Purpose: To assess the perceptions and knowledge of pharmacovigilance and adverse drug reactions (ADRs) reporting among Bachelor of Pharmacy (BPharm) and Doctor of Pharmacy (PharmD) students of selected tertiary institutions in Jordan. Methods: A cross-sectional study involving 434 pharmacy students from three ...

  14. Longitudinal and Cross Sectional Mix Data Approach to Impact ...

    African Journals Online (AJOL)

    Longitudinal and Cross Sectional Mix Data Approach to Impact Assessment: A Case Study of Community Based Natural Resource Management Programme, Nigeria. ... The Component Index Analysis, Productivity Index and Double Differencing techniques were employed for data analysis.The Component Index Analysis ...

  15. Benchmark experiments to test plutonium and stainless steel cross sections

    International Nuclear Information System (INIS)

    Jenquin, U.P.; Bierman, S.R.

    1978-06-01

    Neutronics calculations of physical systems containing fissionable material in various configurations are often necessary to assess criticality safety and economic parameters. Criticality safety of the material must be assured for all configurations in the fuel fabrication, spent fuel reprocessing, and transportation processes. Integral criticality experiments are utilized to evaluate neutron cross sections, test theoretical methods, and validate calculational procedures. The Nuclear Regulatory Commission (NRC) commissioned Battelle, Pacific Northwest Laboratory (PNL) to ascertain the accuracy of the neutron cross sections for the isotopes of plutonium and the constituents of stainless steel and determine if improvements can be made in application to criticality safety analysis. NRC's particular area of interest is in the transportation of light--water reactor spent fuel assemblies. The project was divided into two tasks. The first task was to define a set of integral experimental measurements (benchmarks). The second task is to use these benchmarks in neutronics calculations such that the accuracy of ENDF/B-IV plutonium and stainless steel cross sections can be assessed. The results of the second task should help to identify deficiencies in the neutron cross sections. The results of the first task are given

  16. On the maximum backscattering cross section of passive linear arrays

    DEFF Research Database (Denmark)

    Solymar, L.; Appel-Hansen, Jørgen

    1974-01-01

    The maximum backscattering cross section of an equispaced linear array connected to a reactive network and consisting of isotropic radiators is calculated forn = 2, 3, and 4 elements as a function of the incident angle and of the distance between the elements. On the basis of the results obtained...

  17. Scattering cross section of metal catalyst atoms in silicon nanowires

    DEFF Research Database (Denmark)

    Markussen, Troels; Rurali, R.; Cartoixa, X.

    2010-01-01

    strength of the different metal atoms. We find that Au, Ag, and Cu impurities have very similar scattering cross sections, while Al differs from the rest. Impurities located in the center of the wires scatter significantly more than impurities close to or at the surface. The results for nanowires...

  18. Nuclear structure effects on calculated fast neutron reaction cross sections

    International Nuclear Information System (INIS)

    Avrigeanu, V.

    1992-01-01

    The importance of accurate low-lying level schemes for reaction cross section calculation and need for microscopically calculated levels are proved with reference to fast neutron induced reactions in the A = 50 atomic mass range. The uses of the discrete levels both for normalization of phenomenological level density approaches and within Hauser-Feshbach calculations are discussed in this respect. (Author)

  19. Partial wave analysis for folded differential cross sections

    Science.gov (United States)

    Machacek, J. R.; McEachran, R. P.

    2018-03-01

    The value of modified effective range theory (MERT) and the connection between differential cross sections and phase shifts in low-energy electron scattering has long been recognized. Recent experimental techniques involving magnetically confined beams have introduced the concept of folded differential cross sections (FDCS) where the forward (θ ≤ π/2) and backward scattered (θ ≥ π/2) projectiles are unresolved, that is the value measured at the angle θ is the sum of the signal for particles scattered into the angles θ and π - θ. We have developed an alternative approach to MERT in order to analyse low-energy folded differential cross sections for positrons and electrons. This results in a simplified expression for the FDCS when it is expressed in terms of partial waves and thereby enables one to extract the first few phase shifts from a fit to an experimental FDCS at low energies. Thus, this method predicts forward and backward angle scattering (0 to π) using only experimental FDCS data and can be used to determine the total elastic cross section solely from experimental results at low-energy, which are limited in angular range.

  20. Calculation of vibrational excitation cross-sections in resonant ...

    Indian Academy of Sciences (India)

    WINTEC

    tron is re-emitted after the anion has completed at least one vibration, the nuclear wave function for A– exhibits a reflection from the right turning point, and there is vibrational structure in the resonant scattering cross-sections even for the lowest vibrational excita- tion of the target.1–5 The pronounced vibrational struc-.

  1. Differential cross sections of electron silver scattering at varying ...

    African Journals Online (AJOL)

    The differential scattering cross sections of electron - silver atom are calculated using the Eikonal approximation at incident energies of 50 eV, 60 eV and 70 eV, with the Lenz-Jensen potential. Results obtained are in good agreement with the NIST SRD 64 at scattering angles of about 80 to 180 degrees; and are in very ...

  2. Gender preferences among antenatal women: a cross-sectional ...

    African Journals Online (AJOL)

    Background: A balanced sex ratio is essential for a stable society. Objective: The main objective of the present research was to study the perceptions of women attending the antenatal care (ANC) facility regarding their gender preferences and family composition. Method: In this cross-sectional study 132 antenatal women ...

  3. Cross section parameterization in the resolved resonance region

    International Nuclear Information System (INIS)

    Larson, N.M.

    1992-01-01

    Experimental techniques, methods, and equipment have evolved to provide more accurate neutron cross section data with better energy resolution. Keeping pace with those developments has been a challenge for data analysts; commensurate improvements in analysis tools are required. In this paper, analysis techniques for neutron time-of-flight data in the resolved resonance region are discussed, with emphasis on contemporary needs

  4. Evaluation of nuclear reaction cross section of some isotopes of ...

    African Journals Online (AJOL)

    Coupled-channels optical model code OPTMAN is used as an alternative to experimental approach to evaluate the total reaction cross section for four different isotopes of Plutonium as an example of heavy rotational nuclei of the transuranium elements over an energy range of 10 to 20 MeV. The selected isotopes are the ...

  5. Reference Cross Sections for Charged-particle Monitor Reactions

    Czech Academy of Sciences Publication Activity Database

    Hermanne, A.; Ignatyuk, A. V.; Capote, R.; Carlson, B. V.; Engle, J. W.; Kellett, M. A.; Kibédi, T.; Kim, G.; Kondev, F. G.; Hussain, M.; Lebeda, Ondřej; Luca, A.; Nagai, Y.; Naik, H.; Nichols, A. L.; Nortier, F. M.; Suryanarayana, S. V.; Takacs, S.; Tarkanyi, F. T.; Verpelli, M.

    2018-01-01

    Roč. 148, SI (2018), s. 338-382 ISSN 0090-3752 Institutional support: RVO:61389005 Keywords : deuteron induced reactions * proton induced reactions * cross sections Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders OBOR OECD: Nuclear physics Impact factor: 1.146, year: 2016

  6. Measurement of proton inelastic scattering cross sections on fluorine

    Energy Technology Data Exchange (ETDEWEB)

    Chiari, M., E-mail: chiari@fi.infn.it [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy); Caciolli, A. [Department of Physics and Astronomy, University of Padua and INFN Padua, Padova (Italy); Calzolai, G. [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy); Climent-Font, A. [CMAM, Universidad Autonoma de Madrid, Madrid (Spain); Lucarelli, F.; Nava, S. [Department of Physics and Astronomy, University of Florence and INFN Florence, Sesto Fiorentino (Italy)

    2016-10-01

    Differential cross-sections for proton inelastic scattering on fluorine, {sup 19}F(p,p’){sup 19}F, from the first five excited levels of {sup 19}F at 110, 197, 1346, 1459 and 1554 keV were measured for beam energies from 3 to 7 MeV at a scattering angle of 150° using a LiF thin target (50 μg/cm{sup 2}) evaporated on a self-supporting C thin film (30 μg/cm{sup 2}). Absolute differential cross-sections were calculated with a method not dependent on the absolute values of collected beam charge and detector solid angle. The validity of the measured inelastic scattering cross sections was then tested by successfully reproducing EBS spectra collected from a thick Teflon (CF{sub 2}) target. As a practical application of these measured inelastic scattering cross sections in elastic backscattering spectroscopy (EBS), the feasibility of quantitative light element (C, N and O) analysis in aerosol particulate matter samples collected on Teflon by EBS measurements and spectra simulation is demonstrated.

  7. Evaluated activation cross-sections and intercomparison of the ...

    Indian Academy of Sciences (India)

    Evaluated activation cross-sections and intercomparison of the production parameters for the medically relevant radioisotopes 64Cu and 86Y ... Physics Department, Cyclotron Facility, Nuclear Research Centre, Atomic Energy Authority, Cairo 13759, Egypt; Department of Physics, Faculty of Science, Zagzig University, Ash ...

  8. Quantifying uncertainties in the high-energy neutrino cross-section

    Indian Academy of Sciences (India)

    2012-11-10

    differential) cross-sections. Meanwhile, the tabulated cross-sections for protons, neutrons and isoscalar targets are available from [33]; differential cross-sections are available upon request. Any measured deviation from these ...

  9. Evaluation of cross-section uncertainties using physical constraints for 238U, 239Pu

    International Nuclear Information System (INIS)

    De Saint Jean, Cyrille; Privas, Edwin; Archier, Pascal; Noguere, Gilles; Litaize, Olivier; Leconte, Pierre; Bernard, David

    2014-01-01

    Neutron-induced reactions between 0 eV and 20 MeV are based on various physical properties such as nuclear reaction models, microscopic and integral measurements. Most of the time, the evaluation work is done independently between the resolved resonance range and the continuum, giving rise to mismatches for the cross-sections, larger uncertainties on boundary and no cross-correlation between high-energy domain and resonance range. In addition the use of integral experiment is sometimes only related to central values (evaluation is 'working fine' on a dedicated set of benchmarks) and reductions of uncertainties are not straightforward on cross-sections themselves: working fine could be mathematically reflected by a reduced uncertainty. As the CIELO initiative is to bring experts in each field to propose/discuss these matters, after having presented the status of 238 U and 239 Pu cross-sections covariances evaluation (for JEFF-3.2 as well as the WPEC SG34 subgroup), this paper will present several methodologies that may be used to avoid such effects on covariances. A first idea based on the use of experiments overlapping two energy domains appeared in the near past. It was reviewed and extended to the use of systematic uncertainties (normalisation for example) and for integral experiments as well. In addition, we propose a methodology taking into account physical constraints on an overlapping energy domain where both nuclear reaction models are used (continuity of both cross-sections and derivatives for example). The use of Lagrange multiplier (related to these constraints) in a classical generalised least square procedure will be exposed. Some academic examples will then be presented for both point-wise and multi-group cross-sections to present the methodologies. In addition, new results for 239 Pu will be presented on resonance range and higher energies to reduce capture and fission cross-section uncertainties by using integral experiments (JEZEBEL experiment as

  10. Shear strength of reinforced concrete circular cross-section beams

    Directory of Open Access Journals (Sweden)

    P. W. G. N. Teixeira

    Full Text Available A proposed adequation of NBR 6118, Item 7.4, related to shear strength of reinforced concrete beams is presented with aims to application on circular cross-section. The actual expressions are most suitable to rectangular cross-section and some misleading occurs when applied to circular sections at determination of VRd2, Vc and Vsw, as consequence of bw (beam width and d (effective depth definitions as well as the real effectiveness of circular stirrups. The proposed adequation is based on extensive bibliographic review and practical experience with a great number of infrastructure elements, such as anchored retaining pile walls, where the use of circular reinforced concrete members is frequent.

  11. Fission fragment angular distributions and fission cross section validation

    International Nuclear Information System (INIS)

    Leong, Lou Sai

    2013-01-01

    The present knowledge of angular distributions of neutron-induced fission is limited to a maximal energy of 15 MeV, with large discrepancies around 14 MeV. Only 238 U and 232 Th have been investigated up to 100 MeV in a single experiment. The n-TOF Collaboration performed the fission cross section measurement of several actinides ( 232 Th, 235 U, 238 U, 234 U, 237 Np) at the n-TOF facility using an experimental set-up made of Parallel Plate Avalanche Counters (PPAC), extending the energy domain of the incident neutron above hundreds of MeV. The method based on the detection of the 2 fragments in coincidence allowed to clearly disentangle the fission reactions among other types of reactions occurring in the spallation domain. I will show the methods we used to reconstruct the full angular resolution by the tracking of fission fragments. Below 10 MeV our results are consistent with existing data. For example in the case of 232 Th, below 10 MeV the results show clearly the variation occurring at the first (1 MeV) and second (7 MeV) chance fission, corresponding to transition states of given J and K (total spin and its projection on the fission axis), and a much more accurate energy dependence at the 3. chance threshold (14 MeV) has been obtained. In the spallation domain, above 30 MeV we confirm the high anisotropy revealed in 232 Th by the single existing data set. I'll discuss the implications of this finding, related to the low anisotropy exhibited in proton-induced fission. I also explore the critical experiments which is valuable checks of nuclear data. The 237 Np neutron-induced fission cross section has recently been measured in a large energy range (from eV to GeV) at the n-TOF facility at CERN. When compared to previous measurements, the n-TOF fission cross section appears to be higher by 5-7 % beyond the fission threshold. To check the relevance of n-TOF data, we simulate a criticality experiment performed at Los Alamos with a 6 kg sphere of 237 Np. This

  12. Mid-IR Absorption Cross-Section Measurements of Hydrocarbons

    KAUST Repository

    Alrefae, Majed Abdullah

    2013-05-01

    Laser diagnostics are fast-response, non-intrusive and species-specific tools perfectly applicable for studying combustion processes. Quantitative measurements of species concentration and temperature require spectroscopic data to be well-known at combustion-relevant conditions. Absorption cross-section is an important spectroscopic quantity and has direct relation to the species concentration. In this work, the absorption cross-sections of basic hydrocarbons are measured using Fourier Transform Infrared (FTIR) spectrometer, tunable Difference Frequency Generation laser and fixed wavelength helium-neon laser. The studied species are methane, methanol, acetylene, ethylene, ethane, ethanol, propylene, propane, 1-butene, n-butane, n-pentane, n-hexane, and n-heptane. The Fourier Transform Infrared (FTIR) spectrometer is used for the measurements of the absorption cross-sections and the integrated band intensities of the 13 hydrocarbons. The spectral region of the spectra is 2800 – 3400 cm-1 (2.9 – 3.6 μm) and the temperature range is 673 – 1100 K. These valuable data provide huge opportunities to select interference-free wavelengths for measuring time-histories of a specific species in a shock tube or other combustion systems. Such measurements can allow developing/improving chemical kinetics mechanisms by experimentally determining reaction rates. The Difference Frequency Generation (DFG) laser is a narrow line-width, tunable laser in the 3.35 – 3.53 μm wavelength region which contains strong absorption features for most hydrocarbons due to the fundamental C-H vibrating stretch. The absorption cross-sections of propylene are measured at seven different wavelengths using the DFG laser. The temperature range is 296 – 460 K which is reached using a Reflex Cell. The DFG laser is very attractive for kinetic studies in the shock tube because of its fast time response and the potential possibility of making species-specific measurements. The Fixed wavelength

  13. Microscopic description of production cross sections including deexcitation effects

    Science.gov (United States)

    Sekizawa, Kazuyuki

    2017-07-01

    Background: At the forefront of the nuclear science, production of new neutron-rich isotopes is continuously pursued at accelerator laboratories all over the world. To explore the currently unknown territories in the nuclear chart far away from the stability, reliable theoretical predictions are inevitable. Purpose: To provide a reliable prediction of production cross sections taking into account secondary deexcitation processes, both particle evaporation and fission, a new method called TDHF+GEMINI is proposed, which combines the microscopic time-dependent Hartree-Fock (TDHF) theory with a sophisticated statistical compound-nucleus deexcitation model, GEMINI++. Methods: Low-energy heavy ion reactions are described based on three-dimensional Skyrme-TDHF calculations. Using the particle-number projection method, production probabilities, total angular momenta, and excitation energies of primary reaction products are extracted from the TDHF wave function after collision. Production cross sections for secondary reaction products are evaluated employing GEMINI++. Results are compared with available experimental data and widely used grazing calculations. Results: The method is applied to describe cross sections for multinucleon transfer processes in 40Ca+124Sn (Ec .m .≃128.54 MeV ), 48Ca+124Sn (Ec .m .≃125.44 MeV ), 40Ca+208Pb (Ec .m .≃208.84 MeV ), 58Ni+208Pb (Ec .m .≃256.79 MeV ), 64Ni+238U (Ec .m .≃307.35 MeV ), and 136Xe+198Pt (Ec .m .≃644.98 MeV ) reactions at energies close to the Coulomb barrier. It is shown that the inclusion of secondary deexcitation processes, which are dominated by neutron evaporation in the present systems, substantially improves agreement with the experimental data. The magnitude of the evaporation effects is very similar to the one observed in grazing calculations. TDHF+GEMINI provides better description of the absolute value of the cross sections for channels involving transfer of more than one proton, compared to the grazing

  14. Neutron cross section measurements on {sup 241}Am

    Energy Technology Data Exchange (ETDEWEB)

    Sage, C.; Gunsing, F. [CEA Saclay, DSM/IRFUISPhN, 91 - Gif-sur-Yvette (France); Sage, C.; Borella, A.; Kopecky, S.; Plompen, A.J.M.; Schillebeeckx, P.; Semkova, V.; Siegler, P. [European Commission, Joint Research Centre, Institute for Reference Materials and Measurements, Geel (Belgium); Sage, C.; Dessagne, P.; Rudolf, G. [IPHC Strasbourg, IN2P3, 67 - Strasbourg (France); Sage, C.; Bouland, O.; Noguere, G. [CEA Cadarache, DEN/CAD/DERISPRC/LEPh, 13 - St Paul-lez-Durance (France); Brossard, C.; Fernandez, A.; Holzhauser, M.; Nastren, C.; Ottmar, H.; Somers, J.; Wastin, F. [European Commission, Joint Research Centre, Institute for Transuranium elements, Karlsruhe (Germany); Bouland, O. [Los Alamos National Laboratory, Theoretical Division, Los Alamos, New Mexico (United States); Semkova, V. [Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Science, Sofia (Bulgaria)

    2009-07-01

    Several measurements of neutron induced reaction cross sections on {sup 241}Am have been performed at the JRC-IRMM in Geel, Belgium. Raw material coming from the Atalante facility of CEA Marcoule has been transformed by JRC-ITU Karlsruhe into suitable {sup 241}AmO{sub 2} samples embedded in Al{sub 2}O{sub 3} and Y{sub 2}O{sub 3} matrices. They were specifically designed for activation and time-of-flight measurements. The irradiations for the {sup 241}Am(n,2n){sup 240}Am reaction cross section were carried out at the 7 MV Van de Graaff accelerator using the activation technique. The measurements were performed in 4 sessions, using quasi mono-energetic neutrons with energies ranging from 8 to 21 MeV produced via the D(d,n){sup 3}He and the T(d,n){sup 4}He reactions. The {sup 241}Am(n,2n) reaction cross section was determined relative to the {sup 27}Al(n,{alpha}){sup 24}Na standard cross section and was investigated for the first time above 15 MeV. The induced activity was measured off-line after the irradiation by standard gamma-ray spectrometry using a high purity germanium detector. A different sample of the same isotope {sup 241}Am has been measured in transmission and capture experiments in the resonance region at the neutron time-of-flight facility Gelina. Concerning the transmission, the experiments were performed during two measurement campaigns, the second one after a recent upgrade of the data acquisition system. The neutron flux was measured using a Li-glass scintillator via the {sup 6}Li(n,{alpha}){sup 3}He reaction. The same sample was used for the capture measurement, in which the detection of the photons produced in the capture events was accomplished by two cylindrical C{sub 6}D{sub 6} detectors. The neutron flux shape was determined with a Frisch gridded {sup 10}B ionisation chamber. This paper will describe the results of the (n,2n) measurement campaign, compared with previously existing data and the current evaluated data libraries Jeff-3.1, BROND-2

  15. Developing Scientific Reasoning Through Drawing Cross-Sections

    Science.gov (United States)

    Hannula, K. A.

    2012-12-01

    Cross-sections and 3D models of subsurface geology are typically based on incomplete information (whether surface geologic mapping, well logs, or geophysical data). Creating and evaluating those models requires spatial and quantitative thinking skills (including penetrative thinking, understanding of horizontality, mental rotation and animation, and scaling). However, evaluating the reasonableness of a cross-section or 3D structural model also requires consideration of multiple possible geometries and geologic histories. Teaching students to create good models requires application of the scientific methods of the geosciences (such as evaluation of multiple hypotheses and combining evidence from multiple techniques). Teaching these critical thinking skills, especially combined with teaching spatial thinking skills, is challenging. My Structural Geology and Advanced Structural Geology courses have taken two different approaches to developing both the abilities to visualize and to test multiple models. In the final project in Structural Geology (a 3rd year course with a pre-requisite sophomore mapping course), students create a viable cross-section across part of the Wyoming thrust belt by hand, based on a published 1:62,500 geologic map. The cross-section must meet a number of geometric criteria (such as the template constraint), but is not required to balance. Each student tries many potential geometries while trying to find a viable solution. In most cases, the students don't visualize the implications of the geometries that they try, but have to draw them and then erase their work if it does not meet the criteria for validity. The Advanced Structural Geology course used Midland Valley's Move suite to test the cross-sections that they made in Structural Geology, mostly using the flexural slip unfolding algorithm and testing whether the resulting line lengths balanced. In both exercises, students seemed more confident in the quality of their cross-sections when the

  16. Surgical site infection and its associated factors following cesarean section: a cross sectional study from a public hospital in Ethiopia.

    Science.gov (United States)

    Gelaw, Kelemu Abebe; Aweke, Amlaku Mulat; Astawesegn, Feleke Hailemichael; Demissie, Birhanu Wondimeneh; Zeleke, Liknaw Bewket

    2017-01-01

    A cesarean section is a surgical procedure in which incisions are made through a woman's abdomen and uterus to deliver her baby. Surgical site infections are a common surgical complication among patients delivered with cesarean section. Further it caused to increase maternal morbidity, stay of hospital and the cost of treatment. Hospital based cross-sectional study was conducted to assess the magnitude of surgical site infection following cesarean Site Infections and its associated factors at Lemlem Karl hospital July 1, 2013 to June 30, 2016. Retrospective card review was done on 384 women who gave birth via cesarean section at Lemlem Karl hospital from July 1, 2013 to June 30, 2016. Systematic sampling technique was used to select patient medical cards. The data were entered by Epi info version 7.2 then analyzed using Statistical Package for Social Sciences windows version 20. Both bivariate and multivariate logistic regression was done to test association between predictors and dependent variables. P value of cesarean section, the magnitude of surgical site infection following cesarean section Infection was 6.8%. The identified independent risk factors for surgical site infections were the duration of labor AOR=3.48; 95%CI (1.25, 9.68), rupture of membrane prior to cesarean section AOR=3.678; 95%CI (1.13, 11.96) and the abdominal midline incision (AOR=5.733; 95%CI (2.05, 16.00). The magnitude of surgical site infection following cesarean section is low compare to other previous studies. The independent associated factors for surgical site infection after cesarean section in this study: Membranes rupture prior to cesarean section, duration of labor and sub umbilical abdominal incision. In addition to ensuring sterile environment and aseptic surgeries, use of WHO surgical safety checklist would appear to be a very important intervention to reduce surgical site infections.

  17. Cross sections for neutrino and antineutrino neutral current interactions

    International Nuclear Information System (INIS)

    Bosetti, P.C.; Deden, H.; Deutschmann, M.; Fritze, P.; Graessler, H.; Hasert, F.J.; Morfin, J.; Schulte, R.; Schultze, K.; Seyfert, H.; Banerjee, S.; Barnham, K.W.J.; Beuselinck, R.; Butterworth, I.; Clayton, E.F.; Miller, D.B.; Powell, K.J.; Davis, C.L.; Grossman, P.; McGow, R.; Mulvey, J.H.; Myatt, G.; Perkins, D.H.; Pons, R.; Radojicic, O.; Renton, P.; Saitta, B.; Stenger, V.

    1978-01-01

    The cross sections for γ and anti γ neutral current interactions for which the hadron energy is > 15 GeV have been measured. These results, and the ratios of neutral current to charged current sections, are in agreement with the Weinberg-Salam model. Values of sin 2 thetasub(w) have been obtained both with and without the use of a parametrisation for the hadronic part of the interaction; the values are in good agreement with each other and the preferred result, that obtained by the method independent of hadronic models, is sin 2 thetasub(w) = 0.22 +- 0.05. (Auth.)

  18. Vortex breakdown in closed containers with polygonal cross sections

    International Nuclear Information System (INIS)

    Naumov, I. V.; Dvoynishnikov, S. V.; Kabardin, I. K.; Tsoy, M. A.

    2015-01-01

    The vortex breakdown bubble in the confined flow generated by a rotating lid in closed containers with polygonal cross sections was analysed both experimentally and numerically for the height/radius aspect ratio equal to 2. The stagnation point locations of the breakdown bubble emergence and the corresponding Reynolds number were determined experimentally and in addition computed numerically by STAR-CCM+ CFD software for square, pentagonal, hexagonal, and octagonal cross section configurations. The flow pattern and the velocity were observed and measured by combining the seeding particle visualization and the temporal accuracy of laser Doppler anemometry. The vortex breakdown size and position on the container axis were determined for Reynolds numbers, ranging from 1450 to 2400. The obtained results were compared with the flow structure in the closed container of cubical and cylindrical configurations. It is shown that the measured evolution of steady vortex breakdown is in close agreement with the numerical results

  19. Highlights of top quark cross-section measurements at ATLAS

    CERN Document Server

    Wilk, Fabian; The ATLAS collaboration

    2018-01-01

    Measurements of inclusive and differential top-quark production cross sections in proton-proton collisions with the ATLAS detector at the Large Hadron Collider are presented at a center of mass energy of 8 TeV and 13 TeV. An inclusive measurements of top quark pair production as well as measurement of the cross section for single top production in association with a Z boson is is presented and both are compared to the best available theoretical calculations. Two differential measurement of the kinematic properties of top quark events are presented: one involving a single top produced in association with a W boson and one with top-antitop pair events which decay to an allhadronic final state.

  20. Cross sections for electron-C2 collisions

    International Nuclear Information System (INIS)

    Michelin, S.E.; Oliveira, H.L.; Soares, L.S.S.; Veiteinheimer, E.; Luz, C.A.R.; Mazon, K.T.; Fujimoto, M.M.; Lee, M.-T.

    2005-01-01

    In this work, we present a theoretical study on electron-C 2 collisions in the low and intermediate energy ranges. Calculated elastic differential, integral and momentum transfer cross sections as well as grand total (elastic + inelastic) and absorption cross sections are reported in the 0.1-1000 eV energy range. A complex optical potential is used to represent the electron-molecule interaction dynamics, whereas the Schwinger variational iterative method combined with the distorted-wave approximation is used to solve the scattering equations. Comparison of the present calculated results with the available experimental and theoretical data for electron-C 2 H 2 collisions has shown remarkable similarity for incident energies higher than 20 eV. In addition, a sharp shape resonance is located around 2.5 eV and is identified as due to the 1 Π g scattering channel

  1. Extinction cross-section suppression and active acoustic invisibility cloaking

    Science.gov (United States)

    Mitri, F. G.

    2017-10-01

    Invisibility in its canonical form requires rendering a zero extinction cross-section (or energy efficiency) from an active or a passive object. This work demonstrates the successful theoretical realization of this physical effect for an active cylindrically radiating acoustic body, undergoing periodic axisymmetric harmonic vibrations near a flat rigid boundary. Radiating, amplification and extinction cross-sections of the active source are defined. Assuming monopole and dipole modal oscillations of the circular source, conditions are found where the extinction energy efficiency factor of the active source vanishes, achieving total invisibility with minimal influence of the source size. It also takes positive or negative values, depending on its size and distance from the boundary. Moreover, the amplification energy efficiency factor is negative for the acoustically-active source. These effects also occur for higher-order modal oscillations of the active source. The results find potential applications in the development of acoustic cloaking devices and invisibility.

  2. Timoshenko beam element with anisotropic cross-sectional properties

    DEFF Research Database (Denmark)

    Stäblein, Alexander; Hansen, Morten Hartvig

    2016-01-01

    Beam models are used for the aeroelastic time and frequency domain analysis of wind turbines due to their computational efficiency. Many current aeroelastic tools for the analysis of wind turbines rely on Timoshenko beam elements with classical crosssectional properties (EA, EI, etc.). Those cross......-sectional properties do not reflect the various couplings arising from the anisotropic behaviour of the blade material. A twonoded, three-dimensional Timoshenko beam element was therefore extended to allow for anisotropic cross-sectional properties. For an uncoupled beam, the resulting shape functions are identical...... to the original formulation. The new element was implemented into a co-rotational formulation and validated against natural frequencies and several static load cases of previous works....

  3. Electron attachment cross sections obtained from electron attachment spectroscopy

    International Nuclear Information System (INIS)

    Popp, P.; Baumbach, J.I.; Leonhardt, J.W.; Mothes, S.

    1988-01-01

    Electron capture detectors have a high sensitivity for substances with high thermal electron attachment cross sections. The electron attachment spectroscopy makes it possible to change the mean electron energy in such a way that the maximum for dissociative electron attachment is reached. Thus, best operation modes of the detection system as well as significant dependencies of electron attachment coefficients are available. Cross sections for electron attachment as a function of the electron energy are obtained with the knowledge of electron energy distribution functions from Boltzmann equation analysis by a special computer code. A disadvantage of this electron attachment spectroscopy is the superposition of space charge effects due to the decrease of the electron drift velocity with increasing mean electron energy. These influences are discussed. (author)

  4. A dissociative electron attachment cross-section estimator

    International Nuclear Information System (INIS)

    Munro, James J; Harrison, Stephen; Fujimoto, Milton M; Tennyson, Jonathan

    2012-01-01

    Dissociative electron attachment (DEA) is the major process where molecules are destroyed in low-energy plasmas. DEA cross sections are therefore important for a whole variety of applications but are both hard to measure or compute accurately. A method for estimating DEA cross sections based a simple resonance plus survival model is presented. Test results are presented for DEA of molecular oxygen and molecular chlorine, for which experimental measurements are available for comparison, and SiBr and SiBr 2 , for which no previous data is available. The estimator has been implemented as part of Quantemol-N expert system which uses the R-matrix method to predict resonance positions and widths.

  5. Integral bounds for N-body total cross sections

    International Nuclear Information System (INIS)

    Osborn, T.A.; Bolle, D.

    1979-01-01

    We study the behavior of the total cross sections in the three- and N-body scattering problem. Working within the framework of the time-dependent two-Hilbert space scattering theory, we give a simple derivation of integral bounds for the total cross section for all processes initiated by the collision of two clusters. By combining the optical theorem with a trace identity derived by Jauch, Sinha, and Misra, we find, roughly speaking, that if the local pairwise interaction falls off faster than r -3 , then sigma/sub tot/(E) must decrease faster than E/sup -1/2/ at high energy. This conclusion is unchanged if one introduces a class of well-behaved three-body interactions

  6. Cross section generation for LWR pin lattices simulations

    Energy Technology Data Exchange (ETDEWEB)

    Velasquez, Carlos E.; Macedo, Anderson A.P.; Cardoso, Fabiano S.; Pereira, Claubia; Veloso, Maria Auxiliadora F.; Costa, Antonella L. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Instituto Nacional de Ciencia e Tecnologia de Reatores Nucleares Inovadores/CNPq, Brasilia, DF (Brazil); Barros, Graiciany de P. [Comissao Nacional de Energia Nuclear (CNEN), Rio de Janeiro, RJ (Brazil)

    2015-07-01

    The majority of the neutron data library provided with the MCNP code is set at room temperature. Therefore, it is important to generate continuous energy cross section library for MCNP code for different temperatures. To evaluate the methodology used, the criticality calculations obtained using MCNP with the cross section generated at DEN/UFMG, are compared with the criticality data from the International Handbook of Evaluated Reactor Physics Benchmarks Experiments about the PIN lattices for light water reactors. It was used nuclear data from the ENDF-VII.1, JEFF-3.1 and TENDL-2014, which were processed using the NJOY99 code for different energies and temperatures. This code provides the nuclear data in ACE libraries, which then are added to MCNP libraries to perform the simulations. The results indicate the methodology efficiency developed by DEN/UFMG. (author)

  7. Simultaneous Evaluation of Fission Cross Sections for Cm Isotopes

    Directory of Open Access Journals (Sweden)

    Lee Y.-O.

    2010-03-01

    Full Text Available Fission Cross Sections for a complete set of Cm-isotopes, 240-250Cm, have been calculated in the incident energy range from above resonance region to 20 MeV. This work aims at providing the fission cross sections with consistent set of model parameters for Cm isotopes, as a part of a complete evaluation including covariance files for several minor actinides which play a great role in the Advanced Fuel Cycle (AFC design and applications as well as the design of new generation of nuclear reactors (GEN-IV. This was accomplished by means of computational analyses carried out with the nuclear model code EMPIRE-2.19 which is the modular system of nuclear reaction codes. A Fission model of this work took into account transmission derived in the WKB approximation within an optical model through a double-humped fission barrier.

  8. 23Na(p,γ)24Mg Cross Section Measurements

    Science.gov (United States)

    Boeltzig, Axel; Best, Andreas; deBoer, Richard J.; DiLeva, Antonino; Imbriani, Gianluca; Junker, Matthias; Wiescher, Michael

    2018-01-01

    As a link between the NeNa and MgAl cycles in stellar burning, the reaction 23Na(p,γ)24Mg is of interest for various astrophysical scenarios, such as AGB stars. A combined effort at the Laboratory for Underground Nuclear Astrophysics (LUNA) and the Nuclear Science Laboratory (NSL) at the University of Notre Dame aims at a cross section determination for the this reaction, to constrain the astrophysical reaction rate by improving the knowledge of the resonance strengths and the non-resonant component. Experiments at LUNA benefit from the underground location at the Gran Sasso National Laboratory which allows for the measurement of resonances at low energies with high sensitivity in a low background environment. Measurements at the University of Notre Dame pursue a determination of the non-resonant cross section at higher energies. We present the two experiments and the status of the data analysis.

  9. Fast-neutron scattering cross sections of elemental silver

    International Nuclear Information System (INIS)

    Smith, A.B.; Guenther, P.T.

    1982-05-01

    Differential neutron elastic- and inelastic-scattering cross sections of elemental silver are measured from 1.5 to 4.0 MeV at intervals of less than or equal to 200 keV and at 10 to 20 scattering angles distributed between 20 and 160 0 . Inelastically-scattered neutron groups are observed corresponding to the excitation of levels at; 328 +- 13, 419 +- 50, 748 +- 25, 908 +- 26, 1150 +- 38, 1286 +- 25, 1507 +- 20, 1623 +- 30, 1835 +- 20 and 1944 +- 26 keV. The experimental results are used to derive an optical-statistical model that provides a good description of the observed cross sections. The measured values are compared with corresponding quantities given in ENDF/B-V

  10. Improved neutron capture cross section of Pu239

    Science.gov (United States)

    Mosby, S.; Bredeweg, T. A.; Chyzh, A.; Couture, A.; Henderson, R.; Jandel, M.; Kwan, E.; O'Donnell, J. M.; Ullmann, J.; Wu, C. Y.

    2014-03-01

    The 239Pu(n ,γ) cross section has been measured over the energy range 10 eV to 1 keV using the Detector for Advanced Neutron Capture Experiments (DANCE) at the Los Alamos Neutron Science Center as part of a campaign to produce precision (n ,γ) measurements on 239Pu. Fission coincidences were measured with a parallel-plate avalanche counter and used to measure the prompt fission γ-ray spectrum in this region to accurately characterize background. The resulting (n ,γ) cross section is generally in agreement with current evaluations. The experimental method utilizes much more detailed information than past measurements on 239Pu and can be used to extend the measurement to higher incident neutron energies.

  11. Fully hadronic ttbar cross section measurement with ATLAS detector

    CERN Document Server

    Bertella, C; The ATLAS collaboration

    2011-01-01

    The top quark pair production cross section in the fully hadronic final state is characterized by a six jet topology, two of which could be identified as originating from a b-quark using ATLAS b-tagging algorithms. Compared to other decay channels, this final state presents an advantageous larger branching ratio; on the other hand it suffers from a very large QCD multi-jet background, generally difficult to estimate from Monte Carlo simulation and therefore evaluated using data-driven techniques. It is essential, to efficiently trigger on these fully hadronic ttbar events, to use dedicated triggers. An overview of the analysis for ttbar production cross section measurement in the fully hadronic final state and the state-of-the-art of the b-jet trigger performance estimation are presented in this contribution.

  12. PIA and REWIND: Two New Methodologies for Cross Section Adjustment

    Energy Technology Data Exchange (ETDEWEB)

    Palmiotti, G.; Salvatores, M.

    2017-02-01

    This paper presents two new cross section adjustment methodologies intended for coping with the problem of compensations. The first one PIA, Progressive Incremental Adjustment, gives priority to the utilization of experiments of elemental type (those sensitive to a specific cross section), following a definite hierarchy on which type of experiment to use. Once the adjustment is performed, both the new adjusted data and the new covariance matrix are kept. The second methodology is called REWIND (Ranking Experiments by Weighting for Improved Nuclear Data). This new proposed approach tries to establish a methodology for ranking experiments by looking at the potential gain they can produce in an adjustment. Practical applications for different adjustments illustrate the results of the two methodologies against the current one and show the potential improvement for reducing uncertainties in target reactors.

  13. Assessment and modification of neutron cross sections via interactive graphics

    International Nuclear Information System (INIS)

    Danchak, M.

    1974-01-01

    A unique interactive graphics analysis system, RIGAS, was devised to allow a user to calculate, display, compare, manipulate, and modify his data without requiring any programming expertise on the part of that user. This was accomplished by establishing human primacy, through extensive human factor considerations, and designing a man--machine dialog. This system resulted in an instrument which maximizes man$s decision-making capability and the computer's speed to improve graphic communications and bring data analysis to a point commensurate with twentieth century technology. RIGAS was applied to neutron cross section assessment and modification, using continous slowing-down theory, to provide a technique which was previously considered feasible but impractical. The slowing-down parameters XI and Age were visually and interactively iterated and coupled with an on-line flux calculation to allow real-time matching of experimental and theoretical neutron spectra. The resulting slowing-down parameters then reflected areas of discrepancy in cross section sets and provided a basis from which recommendations for changes in these sets could be made. The resulting tool conservatively decreased analysis time by a factor of 80 and produced initial recommendations for changes to the cross section sets of depleted uranium and iron. It was found that ENDF/B-II overestimated the effects of inelastic scattering in the keV region for depleted uranium and requires modification of the secondary distributions. The self- shielded capture cross sections in the 10 to 40 keV region also require reduction. The Iron-1124 data set was likewise determined to have too strong a contribution from scattering in the high-keV-- low-MeV region. (U.S.)

  14. Measurement, calculation and evaluation of photon production cross-sections

    International Nuclear Information System (INIS)

    Kocherov, N.P.

    1990-03-01

    The IAEA Specialists' Meeting on Measurement, Calculation and Evaluation of Photon Production Cross-Sections was held in Smolenice, Czechoslovakia, 5-7 February 1990. The meeting was hosted by the Institute of Physics of the Electro-Physical Research Centre, Slovak Academy of Sciences, Bratislava. This report contains the conclusions and recommendations of this meeting. The papers which the participants have presented at the meeting will be published as an INDC Report. (author)

  15. Cross sections and kinematics of proton induced fragmentation of carbon

    International Nuclear Information System (INIS)

    Streibel, T.; Roecher, H.; Huentrup, G.; Heinrich, W.

    1997-01-01

    Charge changing fragmentation cross sections for C at a proton energy of about 70 MeV were measured. The discrepancies between measurement and model predictions indicate the necessity of further investigations. We have also measured distributions of fragment emission angles which can be described using a model with a momentum transfer to the fragmenting nucleus. The developed model leads to predictions for momentum distributions of proton induced target fragments of C at small energies. (orig.)

  16. Nuclear Astrophysics and Neutron Cross Section Measurements Using the ORELA

    Energy Technology Data Exchange (ETDEWEB)

    Winters, R. R.

    2000-08-25

    This is the final report for a research program which has been continuously supported by the AEC, ERDA, or USDOE since 1973. The neutron total and capture cross sections for n + {sup 88}Sr have been measured over the neutron energy range 100 eV to 1 MeV. The report briefly summaries our results and the importance of this work for nucleosynthesis and the optical model.

  17. Cross sections and kinematics of proton induced fragmentation of carbon

    Energy Technology Data Exchange (ETDEWEB)

    Streibel, T.; Roecher, H.; Huentrup, G.; Heinrich, W. [Siegen Univ. (Germany). Dept. of Physics

    1997-09-01

    Charge changing fragmentation cross sections for C at a proton energy of about 70 MeV were measured. The discrepancies between measurement and model predictions indicate the necessity of further investigations. We have also measured distributions of fragment emission angles which can be described using a model with a momentum transfer to the fragmenting nucleus. The developed model leads to predictions for momentum distributions of proton induced target fragments of C at small energies. (orig.)

  18. CROSS-SECTIONAL IMAGING EVALUATION OF RENAL REPLACEMENT LIPOMATOSIS (RRL

    Directory of Open Access Journals (Sweden)

    Deb Kumar Boruah

    2016-06-01

    Full Text Available BACKGROUND Renal replacement lipomatosis is an uncommon benign entity where abundance of fibrofatty tissue proliferation occurs in renal sinus with further extension of proliferated fatty tissues into renal hilum, perinephric and periureteric spaces. It is usually associated with renal atrophy and marked renal parenchymal destruction. Aim of our study was cross-sectional imaging evaluation of Renal Replacement Lipomatosis (RRL. METHODS A hospital based cross-sectional retrospective study was conducted. The study group comprised of 16 patients presenting to the Departments of Radio-diagnosis, Surgery and Urology in a tertiary care hospital from May 2014 to April 2016. All patients were initially evaluated clinically and ultrasonographically followed by cross-sectional imaging modality like Computed Tomography (CT, Magnetic Resonance Imaging (MRI or both. RESULTS Out of 16 patients of renal replacement lipomatosis, 15 patients (93.8% had associated renal pelvic or ureteric calculus while 1 patient (6.2% had left para-aortic mass without associated calculus. Out of fifteen patients of calculus related RRL, 8 patients (53.3% had calculus size more than 40 mm, followed by 4 patients (26.7% who had size from 20 to 40 mm and 3 patients (20% had size less than 20 mm. The mean CT HU value of calculus was 1334±84.5 in our study. Three patients (18.8% had only renal hilar fatty excessive deposition, 1 patient (6.2% had renal hilar and perinephric space fat depositions, 3 patients (18.8% had renal hilar, perinephric and periureteric spaces depositions and 9 patients (56.2% had renal hilar and periureteric excessive fatty depositions. Delayed renal functioning was noted in 9 patients (56%, followed by non-functioning in 5 patients (31.2% and 2 patients (12.5% had normally functioning kidneys. CONCLUSION Cross-sectional imaging like CT and MRI scan helps in diagnosing RRL and proper delineation of extensions of excessive fatty tissue proliferation.

  19. Updated Higgs cross section at approximate N3LO

    International Nuclear Information System (INIS)

    Bonvini, Marco; Ball, Richard D.; Marzani, Simone

    2014-04-01

    We update our estimate of the cross section for Higgs production in gluon fusion at next-to-next-to-next-to-leading order (N 3 LO) in α s in view of the recent full computation of the result in the soft limit for infinite top mass, which determines a previously unknown constant. We briefly discuss the phenomenological implications. Results are available through the updated version of the ggHiggs code.

  20. Updated Higgs cross section at approximate N3LO

    International Nuclear Information System (INIS)

    Bonvini, Marco; Ball, Richard D; Forte, Stefano; Marzani, Simone; Ridolfi, Giovanni

    2014-01-01

    We update our estimate of the cross section for Higgs production in gluon fusion at next-to-next-to-next-to-leading order in α s in view of the recent full computation of the result in the soft limit for infinite top mass, which determines a previously unknown constant. We briefly discuss the phenomenological implications. Results are available through the updated version of the ggHiggs code. (paper)

  1. Inclusive parton cross sections in photoproduction and photon structure

    International Nuclear Information System (INIS)

    Ahmed, T.; Aid, S.; Andreev, V.

    1995-04-01

    Photoproduction of 2-jet events is studied with the H1 detector at HERA. Parton cross sections are extracted from the data by an unfolding method using leading order parton-jet correlations of a QCD generator. The gluon distribution in the photon is derived in the fractional momentum range 0.04≤x≤1 at the average factorization scale 75 GeV 2 . (orig.)

  2. Nuclear Astrophysics and Neutron Cross Section Measurements Using the ORELA

    International Nuclear Information System (INIS)

    Winters, R. R.

    2000-01-01

    This is the final report for a research program which has been continuously supported by the AEC, ERDA, or USDOE since 1973. The neutron total and capture cross sections for n + 88 Sr have been measured over the neutron energy range 100 eV to 1 MeV. The report briefly summaries our results and the importance of this work for nucleosynthesis and the optical model

  3. Overview of recent U235 neutron cross section evaluation work

    International Nuclear Information System (INIS)

    Lubitz, C.

    1998-10-01

    This report is an overview (through 1997) of the U235 neutron cross section evaluation work at Oak Ridge National Laboratory (ORNL), AEA Technology (Harwell) and Lockheed Martin Corp.-Schenectady (LMS), which has influenced, or appeared in, ENDF/B-VI through Release 5. The discussion is restricted to the thermal and resolved resonance regions, apart from some questions about the unresolved region which still need investigation. The important role which benchmark testing has played will be touched on

  4. The total top-pair production cross section at NNLL

    Energy Technology Data Exchange (ETDEWEB)

    Beneke, M. [Physik Department T31, James-Franck-Straße, Technische Universität München, D-85748 Garching (Germany); Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen (Germany); Falgari, P., E-mail: p.falgari@uu.nl [Institute for Theoretical Physics and Spinoza Institute, Utrecht University, 3508 TD Utrecht (Netherlands); Klein, S. [Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen (Germany); Piclum, J. [Physik Department T31, James-Franck-Straße, Technische Universität München, D-85748 Garching (Germany); Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen (Germany); Schwinn, C. [Albert-Ludwigs Universität Freiburg, Physikalisches Institut, D-79104 Freiburg (Germany); Ubiali, M.; Yan, F. [Institut für Theoretische Teilchenphysik und Kosmologie, RWTH Aachen University, D-52056 Aachen (Germany)

    2013-01-15

    We present results for the total top-pair production cross section at the Tevatron and the LHC. Our predictions supplement fixed-order results with resummation of soft logarithms and Coulomb singularities to next-to-next-to-leading (NNLL) logarithmic accuracy and include top-antitop bound-state effects. The effects of resummation, the dependence on the PDF set used, the residual sources of theoretical uncertainty and their implication for measurements of the top-quark mass are discussed.

  5. Status of neutron cross sections for reactor dosimetry

    International Nuclear Information System (INIS)

    Vlasov, M.F.; Fabry, A.; McElroy, W.N.

    1977-03-01

    The status of current international efforts to develop standardized sets of evaluated energy-dependent (differential) neutron cross sections for reactor dosimetry is reviewed. The status and availability of differential data are considered, some recent results of the data testing of the ENDF/B-IV dosimetry file using 252 Cf and 235 U benchmark reference neutron fields are presented, and a brief review is given of the current efforts to characterize and identify dosimetry benchmark radiation fields

  6. Cross-section curvature effect in plasmonic ring lasers

    Science.gov (United States)

    Shi, Feifei; Liu, Xudong; Gong, Xin; Zhang, Zhaoyu

    2013-09-01

    Nanolasers have shown their potential in optical communication and information storage, due to their tiny footprint, potential high modulation rate and light spot under diffraction limit. In recent years, many structures use metal as whole or part of the cavity to achieve light confinement at subwavelength scale. In this paper, we propose and compare two novel types of hybrid plasmonic lasers, both with an ultrathin insulator layer sandwiched by a ring shape semiconductor and planar silver layer. The lasers differ in their cross-section curvature on the interface of metal and insulator. Finite difference time domain (FDTD) method is used to calculate and optimize these two ring laser structures. The resonant wavelength is set around 490 nm. The ultrathin thickness of the insulator layer makes photonic modes hybridize with surface plasmon plaritons (SPPs) at Ag-insulator interface, which confines the light field strongly in the ultrathin layer. The SPPs carry high momentum and high effective refractive index to TM mode. Whispering gallery mode is achieved according to strong feedback at the ring boundary by total internal reflection. The ring lasers have relatively high Q factors, approaching 100, at 250 nm radius and mode confinement around λ2/360. The mode volume can be shrunk to 0.1(λ/n)3 and 0.01(λ/n)3 respectively, which leads to Purcell factors around 70 for square cross-section and 380 for circle cross-section. We discuss the curvature effects on the mode volume and on the quality factor which accounts for the high Purcell factor for the circle cross-section.

  7. Removal cross section for 14 mev neutrons in constructional materials

    International Nuclear Information System (INIS)

    Vasvary, L.; Divos, F.; Peto, G.; Csikai, J.; Mumba, N.K.

    1985-01-01

    Using flight time difference the direct and scattered neutrons and gammas produced in the target head and samples were separated. With this method the attenuation of primary neutrons and gammas originating from the target head has been studied. Thickness dependence of the secondary gamma yield from extended samples of Al, Fe, Pb, paraffin and reinforced concrete was also measured. Results indicate a geometry dependence of the removal cross sections

  8. Thermal neutron scattering cross sections of beryllium and magnesium oxides

    International Nuclear Information System (INIS)

    Al-Qasir, Iyad; Jisrawi, Najeh; Gillette, Victor; Qteish, Abdallah

    2016-01-01

    Highlights: • Neutron thermalization in BeO and MgO was studied using Ab initio lattice dynamics. • The BeO phonon density of states used to generate the current ENDF library has issues. • The BeO cross sections can provide a more accurate ENDF library than the current one. • For MgO an ENDF library is lacking: a new accurate one can be built from our results. • BeO is a better filter than MgO, especially when cooled down to 77 K. - Abstract: Alkaline-earth beryllium and magnesium oxides are fundamental materials in nuclear industry and thermal neutron scattering applications. The calculation of the thermal neutron scattering cross sections requires a detailed knowledge of the lattice dynamics of the scattering medium. The vibrational properties of BeO and MgO are studied using first-principles calculations within the frame work of the density functional perturbation theory. Excellent agreement between the calculated phonon dispersion relations and the experimental data have been obtained. The phonon densities of states are utilized to calculate the scattering laws using the incoherent approximation. For BeO, there are concerns about the accuracy of the phonon density of states used to generate the current ENDF/B-VII.1 libraries. These concerns are identified, and their influences on the scattering law and inelastic scattering cross section are analyzed. For MgO, no up to date thermal neutron scattering cross section ENDF library is available, and our results represent a potential one for use in different applications. Moreover, the BeO and MgO efficiencies as neutron filters at different temperatures are investigated. BeO is found to be a better filter than MgO, especially when cooled down, and cooling MgO below 77 K does not significantly improve the filter’s efficiency.

  9. Cross-sectional transmission electron microscopy of semiconductors

    International Nuclear Information System (INIS)

    Sadana, D.K.

    1982-10-01

    A method to prepare cross-sectional (X) semiconductor specimens for transmission electron microscopy (TEM) has been described. The power and utility of XTEM has been demonstrated. It has been shown that accuracy and interpretation of indirect structural-defects profiling techniques, namely, MeV He + channeling and secondary ion mass spectrometry (SIMS) can be greatly enhanced by comparing their results with those obtained by XTEM from the same set of samples

  10. The Cross-Section of Expected Stock Returns.

    OpenAIRE

    Fama, Eugene F; French, Kenneth R

    1992-01-01

    Two easily measured variables, size and book-to-market equity, combine to capture the cross-sectional variation in average stock returns associated with market "beta", size, leverage, book-to-market equity, and earnings-price ratios. Moreover, when the tests allow for variation in "beta" that is unrelated to size, t he relation between market "beta" and average return is flat, even when "beta" is the only explanatory variable. Copyright 1992 by American Finance Association.

  11. The determination of thermal neutron cross section of 81Br

    International Nuclear Information System (INIS)

    Kovacs, Luciana; Zamboni, Cibele B.; Dalaqua Junior, Leonardo

    2009-01-01

    In this investigation several standard materials were used to determine the thermal neutron cross section of 81 Br. This nuclear parameter is an important data to perform several quantitative investigations, mainly in medical area. In other to confirm and to reduce the uncertainty, a new measurement was preformed using thermal neutron at IEA-R1 nuclear reactor of IPEN/CNEN-SP. The result obtained is compatible with the tabulated value and present small uncertainly. (author)

  12. ${\\rm t\\bar{t}}$ cross section measurements in CMS

    CERN Document Server

    Diez Pardos, C.

    2016-01-01

    An overview of the most recent measurements of inclusive top quark pair production cross section is presented. The results are obtained using data collected with the CMS experiment in proton-proton collisions at centre-of-mass energies of 5.02, 7, 8 and 13 TeV. The data are compared with the predictions from perturbative QCD calculations at full NNLO+NNLL accuracy.

  13. Modeled Neutron Induced Nuclear Reaction Cross Sections for Radiochemsitry in the region of Thulium, Lutetium, and Tantalum I. Results of Built in Spherical Symmetry in a Deformed Region

    Energy Technology Data Exchange (ETDEWEB)

    Hoffman, R. D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-09-06

    We have developed a set of modeled nuclear reaction cross sections for use in radiochemical diagnostics. Systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for targets ranging from Terbium (Z = 65) to Rhenium (Z = 75). Of particular interest are the cross sections on Tm, Lu, and Ta including reactions on isomeric targets.

  14. Estimation of (n,f) Cross-Sections by Measuring Reaction Probability Ratios

    Energy Technology Data Exchange (ETDEWEB)

    Plettner, C; Ai, H; Beausang, C W; Bernstein, L A; Ahle, L; Amro, H; Babilon, M; Burke, J T; Caggiano, J A; Casten, R F; Church, J A; Cooper, J R; Crider, B; Gurdal, G; Heinz, A; McCutchan, E A; Moody, K; Punyon, J A; Qian, J; Ressler, J J; Schiller, A; Williams, E; Younes, W

    2005-04-21

    Neutron-induced reaction cross-sections on unstable nuclei are inherently difficult to measure due to target activity and the low intensity of neutron beams. In an alternative approach, named the 'surrogate' technique, one measures the decay probability of the same compound nucleus produced using a stable beam on a stable target to estimate the neutron-induced reaction cross-section. As an extension of the surrogate method, in this paper they introduce a new technique of measuring the fission probabilities of two different compound nuclei as a ratio, which has the advantage of removing most of the systematic uncertainties. This method was benchmarked in this report by measuring the probability of deuteron-induced fission events in coincidence with protons, and forming the ratio P({sup 236}U(d,pf))/P({sup 238}U(d,pf)), which serves as a surrogate for the known cross-section ratio of {sup 236}U(n,f)/{sup 238}U(n,f). IN addition, the P({sup 238}U(d,d{prime}f))/P({sup 236}U(d,d{prime}f)) ratio as a surrogate for the {sup 237}U(n,f)/{sup 235}U(n,f) cross-section ratio was measured for the first time in an unprecedented range of excitation energies.

  15. Measurements of fusion cross section for 12C +63,65 Cu systems

    International Nuclear Information System (INIS)

    Rocha, C.A. da.

    1987-01-01

    Cross-section measurements for nuclear fusion in the 12 C+ 63.65 Cu system, at 12 C energy range from 0.9 to 1.8 times the Coulomb barrier are presented. In order to detect and to obtain the mass identification of the evaporation residues following the fusion process, the time of flight method was adopted in conjunction with an eletrostatic deflector capable of separating the evaporation residues from the beam particles. The limitation and advantadges of this method of measurement are discussed. The excitation functions were analysed using the unidimensional barrier penetration model with different nuclear potentials. Theoretical fusion cross-section values obtained from this analysis were systematically smaller than our measured values, in the energy region below the Coulomb barrier. In order to discover which channel enhances the fusion cross-section in this region, a coupled channel calculation was performed, with the CCFUS code. The experimental data for the above reactions were compared with the systems 16.18 O+ 63.65 Cu, measured by our group. In this comparison, it was noted that the systems 12 C+ 63.65 Cu, have greater fusion cross section below the Coulomb barrier. The comparison of velocity spectra of the evaporated residues for the two systems shows that 12 C+ 63 Cu has a strong reaction channel that was not present in the 12 C+ 65 Cu system. (author) [pt

  16. Handbook of LHC Higgs Cross Sections: 3. Higgs Properties

    Energy Technology Data Exchange (ETDEWEB)

    Heinemeyer, S; et al.

    2013-01-01

    This Report summarizes the results of the activities in 2012 and the first half of 2013 of the LHC Higgs Cross Section Working Group. The main goal of the working group was to present the state of the art of Higgs Physics at the LHC, integrating all new results that have appeared in the last few years. This report follows the first working group report Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables (CERN-2011-002) and the second working group report Handbook of LHC Higgs Cross Sections: 2. Differential Distributions (CERN-2012-002). After the discovery of a Higgs boson at the LHC in mid-2012 this report focuses on refined prediction of Standard Model (SM) Higgs phenomenology around the experimentally observed value of 125-126 GeV, refined predictions for heavy SM-like Higgs bosons as well as predictions in the Minimal Supersymmetric Standard Model and first steps to go beyond these models. The other main focus is on the extraction of the characteristics and properties of the newly discovered particle such as couplings to SM particles, spin and CP-quantum numbers etc.

  17. (n,α reactions cross section research at IPPE

    Directory of Open Access Journals (Sweden)

    Giorginis G.

    2012-02-01

    Full Text Available An experimental set-up based on an ionization chamber with a Frisch grid and wave form digitizer was used for (n,α cross section measurements. Use of digital signal processing allowed us to select a gaseous cell inside the sensitive area of the ionization chamber and determine the target atoms in it with high accuracy. This kind of approach provided us with a powerful method to suppress background arising from the detector structure and parasitic reactions on the working gas components. This method is especially interesting to study neutron reactions with elements for which solid target preparation is difficult (noble gases for example. In the present experiments we used a set of working gases which contained admixtures of nitrogen, oxygen, neon, argon and boron. Fission of 238U was used as neutron flux monitor. The cross section of the (n,α reaction for 16O, 14N, 20Ne, 36Ar, 40Ar and the yield ratio α0/α1 of 10B(n,α0 to 10B(n,α1 reactions was measured for neutron energies between 1.5 and 7 MeV. Additionally a measurement of the 50Cr(n,α cross section using a solid chromium target is also reported.

  18. Thermal neutron cross section measurements for technetium-99

    International Nuclear Information System (INIS)

    Yates, M.A.; Schroeder, N.C.; Fowler, M.M.

    1993-01-01

    Technetium, because of its long half-like (213,000 years) and ability to migrate in the environment, is a primary contributor to the long-term radioactivity related risk associated with geologic nuclear waste disposal. One proposal for converting technetium to an environmentally benign element investigating transmutation with an accelerator-based system, (i.e., Accelerator Transmutation of Waste, ATW). Planning for efficient processing of technetium through the transmuter will require knowledge of the thermal neutron cross section for the 99 Tc (n,γ) 100 Tc reaction. The authors have recently remeasured this cross section. Weighed aliquots (19-205 μg) of a NIST traceable 99 Tc standard were irradiated for 30-150 sec using the pneumatic open-quotes rabbitclose quotes system of LANL's Omega West Reactor. The two gamma rays from the 15.7-sec half-life product were measured immediately after irradiation on a high-resolution Ge detector. Thermal fluxes were measured using gold foils and Cd wrapped gold foils. The observation cross section is 19 ± 1 b. This agrees well with the 1977 value but has half the uncertainty

  19. Uranium, thorium and bismuth photofission cross sections at high energies

    International Nuclear Information System (INIS)

    Tavares, O.A.P.

    1973-01-01

    The U 238 , Th 232 and Bi 209 photofission using nuclear emulsion technique for fission fragments detection is presented. The photofission cross sections were measured using Bremsstrahlung photon which were produced irradiating thin tungsten radiators with electrons accelerated at the energy range from 1,0 to 5,5 GeV in the ''Deutsches Elektronen Synchrotron'' (Hamburg), and aluminium radiator with electrons accelarated at 16,0 GeV in Stanford Linear Accelerator Center. A special revelation technique for nuclear emulsion pellicles loaded with uranium and thorium, allowed the discrimination between alpha particles tracks and fission fragments tracks. The results show a decrease in the cross sections, which is in good agreement, within experimental errors, with the conclusions of other authors. The estimations from the two-step mechanism for high energy nuclear reactions (intranuclear cascade followed by fission-evaporation competition) show that, the primary interaction according to the photomesonic model and the quasi-deuteron photon interaction are sufficient to explain the general behavior exhibited by photofission cross sections for investigated nuclei. The calculations show a resonant structure around 300 MeV, with a width at half maximum of 200 MeV, and another not so pronounced, near to 700 MeV. (Author) [pt

  20. Fully hadronic ttbar cross section measurement with ATLAS detector

    CERN Document Server

    Bertella, Claudia

    2011-01-01

    The top quark pair production cross section in the fully hadronic final state is characterized by a six jet topology, two of which could be identified as originating from a b-quark using ATLAS b-tagging algorithms. Compared to other decay channels, this final state presents an advantageous larger branching ratio; on the other hand it suffers from a very large QCD multi-jet background, generally difficult to estimate from Monte Carlo simulation and therefore evaluated using data-driven techniques. The analysis is performed using 36pb-1 of pp collisions produced at the LHC with a center-of-mass energy of 7 TeV. The observed upper limit is set at 261 pb at 95% confidence level, where the expected Standard Model cross-section for the ttbar process is 165+11-16 pb. In the future, when the LHC luminosity increases, it is essential, to efficiently trigger on these fully hadronic ttbar events, to use dedicated triggers. An overview of the analysis for ttbar production cross section measurement in the fully hadronic f...

  1. Adiabatic theory of Wannier threshold laws and ionization cross sections

    International Nuclear Information System (INIS)

    Macek, J.H.; Ovchinnikov, S.Y.

    1994-01-01

    Adiabatic energy eigenvalues of H 2 + are computed for complex values of the internuclear distance R. The infinite number of bound-state eigenenergies are represented by a function ε(R) that is single valued on a multisheeted Riemann surface. A region is found where ε(R) and the corresponding eigenfunctions exhibit harmonic-oscillator structure characteristic of electron motion on a potential saddle. The Schroedinger equation is solved in the adiabatic approximation along a path in the complex R plane to compute ionization cross sections. The cross section thus obtained joins the Wannier threshold region with the keV energy region, but the exponent near the ionization threshold disagrees with well-accepted values. Accepted values are obtained when a lowest-order diabatic correction is employed, indicating that adiabatic approximations do not give the correct zero velocity limit for ionization cross sections. Semiclassical eigenvalues for general top-of-barrier motion are given and the theory is applied to the ionization of atomic hydrogen by electron impact. The theory with a first diabatic correction gives the Wannier threshold law even for this case

  2. Neutron method and apparatus for determining total cross-section

    International Nuclear Information System (INIS)

    Flaum, C.

    1984-01-01

    This invention relates to the determination of the macroscopic neutron absorption cross section of the geological formation surrounding a borehole. The method comprises passing a logging sonde through the borehole while continuously irradiating the formation with neutrons. The radiation emanating from the formation is monitored to generate a first signal indicative of thermal neutrons and a second signal indicative of epithermal neutrons. Output signals are generated indicative of the spatial distribution of thermal and epithermal neutrons, and are combined to generate a signal representative of the macroscopic neutron absorption cross section of the formation. The apparatus comprises a logging sonde adapted for movement through the borehole and carrying a neutron source; detector means on the sonde for monitoring radiation emanating from the formation to generate signals indicative of thermal and epithermal neutrons; means for generating output signals indicative of the spatial distribution of thermal and epithermal neutrons; and means for combining the two output signals to generate a signal indicative of the macroscopic neutron absorption cross section of the material

  3. The fission cross section of 228Th near threshold

    Science.gov (United States)

    James, G. D.; Syme, D. B.; Grainger, J.

    1984-05-01

    The fission cross section and fragment angular distribution for the reaction 228Th(n, f) have been measured over the neutron energy range 350 keV to 1200 keV at values of the neutron energy resolution in the range 20 keV to 37 keV. An absolute determination of the fission cross section at 1635 keV gave the value 370 ± 32 mb to which the data are normalised. Forty cross-section data points are available but only twenty-two of these allow a trustworthy anisotropy to be quoted. The data confirm the structure noted by Vorotnikov et al. near 450 keV and at 1.1 MeV but also reveal a pronounced resonance at 760 keV. The fragment anisotropy values are predominantly forward peaked and indicate a spin projection K = {1}/{2} for all resonance groups. The way in which the results reflect on our understanding of the fission potential barrier is noted.

  4. A method to obtain new cross-sections transport equivalent

    International Nuclear Information System (INIS)

    Palmiotti, G.

    1988-01-01

    We present a method, that allows the calculation, by the mean of variational principle, of equivalent cross-sections in order to take into account the transport and mesh size effects on reactivity variation calculations. The method validation has been made in two and three dimensions geometries. The reactivity variations calculated in three dimensional hexagonal geometry with seven points by subassembly using two sets of equivalent cross-sections for control rods are in a very good agreement with the ones of a transport, extrapolated to zero mesh size, calculation. The difficulty encountered in obtaining a good flux distribution has lead to the utilisation of a single set of equivalent cross-sections calculated by starting from an appropriated R-Z model that allows to take into account also the axial transport effects for the control rod followers. The global results in reactivity variations are still satisfactory with a good performance for the flux distribution. The main interest of the proposed method is the possibility to simulate a full 3D transport calculation, with fine mesh size, using a 3D diffusion code, with a larger mesh size. The results obtained should be affected by uncertainties, which do not exceed ± 4% for a large LMFBR control rod worth and for very different rod configurations. This uncertainty is by far smaller than the experimental uncertainties. (author). 5 refs, 8 figs, 9 tabs

  5. Absolute measurements of chlorine Cl+ cation single photoionization cross section

    International Nuclear Information System (INIS)

    Hernández, E.M.; Juárez, A.M.; Kilcoyne, A.L.D.; Aguilar, A.; Hernández, L.; Antillón, A.; Macaluso, D.; Morales-Mori, A.; González-Magaña, O.; Hanstorp, D.; Covington, A.M.; Davis, V.; Calabrese, D.; Hinojosa, G.

    2015-01-01

    The photoionization of Cl + leading to Cl 2+ was measured in the photon energy range of 19.5–28.0 eV. A spectrum with a photon energy resolution of 15 meV normalized to absolute cross-section measurements is presented. The measurements were carried out by merging a Cl + ion beam with a photon beam of highly monochromatic synchrotron radiation at the Advanced Light Source at Lawrence Berkeley National Laboratory. The measured photoionization of Cl + consists of several autoionization resonances surperimposed on the direct photoionization signal. Most of the prominent resonances are assigned to members of Rydberg series originating from the singlet ground state and from metastable triplet levels within the ground-state configuration of Cl + . The direct ionization cross section is no larger than 12 Mb. - Highlights: • The single photoionization absolute cross section of Cl + ion was measured. • Numerous resonances were identified as belonging to Rydberg series. • A large population of the metastable Cl + ( 1 D 2 ) was identified. • Identified resulting Cl 2+ state terms correspond to 2 D 5/2 and 2 D 3/2

  6. Monostatic radar cross section of flying wing delta planforms

    Directory of Open Access Journals (Sweden)

    Sevoor Meenakshisundaram Vaitheeswaran

    2017-04-01

    Full Text Available The design of the flying wing and its variants shapes continues to have a profound influence in the design of the current and future use of military aircraft. There is very little in the open literature available to the understanding and by way of comparison of the radar cross section of the different wing planforms, for obvious reasons of security and sensitivity. This paper aims to provide an insight about the radar cross section of the various flying wing planforms that would aid the need and amount of radar cross section suppression to escape detection from surveillance radars. Towards this, the shooting and bouncing ray method is used for analysis. In this, the geometric optics theory is first used for launching and tracing the electromagnetic rays to calculate the electromagnetic field values as the waves bounce around the target. The physical optics theory is next used to calculate the final scattered electric field using the far field integration along the observation direction. For the purpose of comparison, all the planform shapes are assumed to be having the same area, and only the aspect ratio and taper ratio are varied to feature representative airplanes.

  7. Origami tubes with reconfigurable polygonal cross-sections.

    Science.gov (United States)

    Filipov, E T; Paulino, G H; Tachi, T

    2016-01-01

    Thin sheets can be assembled into origami tubes to create a variety of deployable, reconfigurable and mechanistically unique three-dimensional structures. We introduce and explore origami tubes with polygonal, translational symmetric cross-sections that can reconfigure into numerous geometries. The tubular structures satisfy the mathematical definitions for flat and rigid foldability, meaning that they can fully unfold from a flattened state with deformations occurring only at the fold lines. The tubes do not need to be straight and can be constructed to follow a non-linear curved line when deployed. The cross-section and kinematics of the tubular structures can be reprogrammed by changing the direction of folding at some folds. We discuss the variety of tubular structures that can be conceived and we show limitations that govern the geometric design. We quantify the global stiffness of the origami tubes through eigenvalue and structural analyses and highlight the mechanical characteristics of these systems. The two-scale nature of this work indicates that, from a local viewpoint, the cross-sections of the polygonal tubes are reconfigurable while, from a global viewpoint, deployable tubes of desired shapes are achieved. This class of tubes has potential applications ranging from pipes and micro-robotics to deployable architecture in buildings.

  8. Determination of Optimum Cross-section for Oran Highway Revetment

    Science.gov (United States)

    Velioglu, Deniz; Sogut, Erdinc; Guler, Isikhan

    2017-04-01

    Revetments are shore parallel, sloping coastal structures which are built to provide protection from the negative effects of the sea. The revetment mentioned in this study is located in the City of Oran, Algeria and is currently under construction. This study investigates the determination of the optimum revetment cross section for Oran highway, considering both the hydraulic stability of the revetment and economy. The existence of cliffs in the region and the settlement of the City of Oran created a necessity to re-align Oran highway; therefore, it was shifted towards the Gulf of Oran. Approximately 1 km of the highway is to be constructed on the Mediterranean Sea due to the new alignment. In order to protect the sea side of the road from the adverse effects of the sea, a revetment was designed. The proposed cross section had an armour layer composed of 23 tons of antifer units and regular placement of armour units was recommended. In order to check the hydraulic stability of the proposed section, physical model tests were performed in the laboratory of LEM (Laboratoire d'Etudes Maritimes) in Algeria, using the pre-determined design wave conditions. The physical model tests revealed that the trunk of the revetment was totaly damaged. Accordingly, the proposed section was found insufficient and certain modifications were required. The first modification was made in the arrangement of armour units, changing them from regular to irregular. After testing the new cross section, it was observed that the revetment was vulnerable to breaking wave attack due to the toe geometry and thus the toe of the revetment had to be re-shaped. Therefore, the second option was to reduce the toe elevation. It was observed that even though the revetment trunk was safe, the damage in the toe was not in acceptable limits. The new cross section was found insufficient and as the final option, the weight of the antifer units used in the armour layer was increased, the toe length of the

  9. Grey literature in systematic reviews: a cross-sectional study of the contribution of non-English reports, unpublished studies and dissertations to the results of meta-analyses in child-relevant reviews.

    Science.gov (United States)

    Hartling, Lisa; Featherstone, Robin; Nuspl, Megan; Shave, Kassi; Dryden, Donna M; Vandermeer, Ben

    2017-04-19

    Systematic reviews (SRs) are an important source of information about healthcare interventions. A key component of a well-conducted SR is a comprehensive literature search. There is limited evidence on the contribution of non-English reports, unpublished studies, and dissertations and their impact on results of meta-analyses. Our sample included SRs from three Cochrane Review Groups: Acute Respiratory Infections (ARI), Infectious Diseases (ID), Developmental Psychosocial and Learning Problems (DPLP) (n = 129). Outcomes included: 1) proportion of reviews that searched for and included each study type; 2) proportion of relevant studies represented by each study type; and 3) impact on results and conclusions of the primary meta-analysis for each study type. Most SRs searched for non-English studies; however, these were included in only 12% of reviews and represented less than 5% of included studies. There was a change in results in only four reviews (total sample = 129); in two cases the change did not have an impact on the statistical or clinical significance of results. Most SRs searched for unpublished studies but the majority did not include these (only 6%) and they represented 2% of included studies. In most cases the impact of including unpublished studies was small; a substantial impact was observed in one case that relied solely on unpublished data. Few reviews in ARI (9%) and ID (3%) searched for dissertations compared to 65% in DPLP. Overall, dissertations were included in only nine SRs and represented less than 2% of included studies. In the majority of cases the change in results was negligible or small; in the case where a large change was noted, the estimate was more conservative without dissertations. The majority of SRs searched for non-English and unpublished studies; however, these represented a small proportion of included studies and rarely impacted the results and conclusions of the review. Inclusion of these study types may have an impact

  10. Grey literature in systematic reviews: a cross-sectional study of the contribution of non-English reports, unpublished studies and dissertations to the results of meta-analyses in child-relevant reviews

    Directory of Open Access Journals (Sweden)

    Lisa Hartling

    2017-04-01

    Full Text Available Abstract Background Systematic reviews (SRs are an important source of information about healthcare interventions. A key component of a well-conducted SR is a comprehensive literature search. There is limited evidence on the contribution of non-English reports, unpublished studies, and dissertations and their impact on results of meta-analyses. Methods Our sample included SRs from three Cochrane Review Groups: Acute Respiratory Infections (ARI, Infectious Diseases (ID, Developmental Psychosocial and Learning Problems (DPLP (n = 129. Outcomes included: 1 proportion of reviews that searched for and included each study type; 2 proportion of relevant studies represented by each study type; and 3 impact on results and conclusions of the primary meta-analysis for each study type. Results Most SRs searched for non-English studies; however, these were included in only 12% of reviews and represented less than 5% of included studies. There was a change in results in only four reviews (total sample = 129; in two cases the change did not have an impact on the statistical or clinical significance of results. Most SRs searched for unpublished studies but the majority did not include these (only 6% and they represented 2% of included studies. In most cases the impact of including unpublished studies was small; a substantial impact was observed in one case that relied solely on unpublished data. Few reviews in ARI (9% and ID (3% searched for dissertations compared to 65% in DPLP. Overall, dissertations were included in only nine SRs and represented less than 2% of included studies. In the majority of cases the change in results was negligible or small; in the case where a large change was noted, the estimate was more conservative without dissertations. Conclusions The majority of SRs searched for non-English and unpublished studies; however, these represented a small proportion of included studies and rarely impacted the results and conclusions of the

  11. FENDL/E-2.0. Evaluated nuclear data library of neutron-nucleus interaction cross sections and photon production cross sections and photon-atom interaction cross sections for fusion applications. Version 1, March 1997. Summary documentation

    International Nuclear Information System (INIS)

    Pashchenko, A.B.; Wienke, H.

    1998-01-01

    This document presents the description of a physical tape containing the basic evaluated nuclear data library of neutron-nucleus interaction cross sections, photon production cross sections and photon-atom interaction cross sections for fusion applications. It is part of the evaluated nuclear data library for fusion applications FENDL-2. The data are available cost-free from the Nuclear Data Section upon request. The data can also be retrieved by the user via online access through international computer networks. (author)

  12. Estimated 55Mn and 90Zr cross section covariances in the fast neutron energy region

    International Nuclear Information System (INIS)

    Pigni, M.T.; Herman, M.; Oblozinsky, P.

    2008-01-01

    We completed estimates of neutron cross section covariances for 55 Mn and 90 Zr, from keV range to 25 MeV, considering the most important reaction channels, total, elastic, inelastic, capture, and (n,2n). The nuclear reaction model code EMPIRE was used to calculate sensitivity to model parameters by perturbation of parameters that define the optical model potential, nuclear level densities and strength of the pre-equilibrium emission. The sensitivity analysis was performed with the set of parameters which reproduces the ENDF/B-VII.0 cross sections. The experimental data were analyzed and both statistical and systematic uncertainties were extracted from almost 30 selected experiments. Then, the Bayesian code KALMAN was used to combine the sensitivity analysis and the experiments to obtain the evaluated covariance matrices

  13. A Time Projection Chamber for High Accuracy and Precision Fission Cross-Section Measurements

    Energy Technology Data Exchange (ETDEWEB)

    T. Hill; K. Jewell; M. Heffner; D. Carter; M. Cunningham; V. Riot; J. Ruz; S. Sangiorgio; B. Seilhan; L. Snyder; D. M. Asner; S. Stave; G. Tatishvili; L. Wood; R. G. Baker; J. L. Klay; R. Kudo; S. Barrett; J. King; M. Leonard; W. Loveland; L. Yao; C. Brune; S. Grimes; N. Kornilov; T. N. Massey; J. Bundgaard; D. L. Duke; U. Greife; U. Hager; E. Burgett; J. Deaven; V. Kleinrath; C. McGrath; B. Wendt; N. Hertel; D. Isenhower; N. Pickle; H. Qu; S. Sharma; R. T. Thornton; D. Tovwell; R. S. Towell; S.

    2014-09-01

    The fission Time Projection Chamber (fissionTPC) is a compact (15 cm diameter) two-chamber MICROMEGAS TPC designed to make precision cross-section measurements of neutron-induced fission. The actinide targets are placed on the central cathode and irradiated with a neutron beam that passes axially through the TPC inducing fission in the target. The 4p acceptance for fission fragments and complete charged particle track reconstruction are powerful features of the fissionTPC which will be used to measure fission cross-sections and examine the associated systematic errors. This paper provides a detailed description of the design requirements, the design solutions, and the initial performance of the fissionTPC.

  14. High Precision Measurement of the differential W and Z boson cross-sections

    CERN Document Server

    Gasnikova, Ksenia; The ATLAS collaboration

    2017-01-01

    Measurements of the Drell-Yan production of W and Z/gamma bosons at the LHC provide a benchmark of our understanding of perturbative QCD and probe the proton structure in a unique way. The ATLAS collaboration has performed new high precision measurements at center-of-mass energies of 7. The measurements are performed for W+, W- and Z/gamma bosons integrated and as a function of the boson or lepton rapidity and the Z/gamma* mass. Unprecedented precision is reached and strong constraints on Parton Distribution functions, in particular the strange density are found. Z cross sections are also measured at a center-of-mass energies of 8TeV and 13TeV, and cross-section ratios to the top-quark pair production have been derived. This ratio measurement leads to a cancellation of several systematic effects and allows therefore for a high precision comparison to the theory predictions.

  15. Estimated 55Mn and 90Zr cross section covariances in the fast neutron energy region

    Energy Technology Data Exchange (ETDEWEB)

    Pigni,M.T.; Herman, M.; Oblozinsky, P.

    2008-06-24

    We completed estimates of neutron cross section covariances for {sup 55}Mn and {sup 90}Zr, from keV range to 25 MeV, considering the most important reaction channels, total, elastic, inelastic, capture, and (n,2n). The nuclear reaction model code EMPIRE was used to calculate sensitivity to model parameters by perturbation of parameters that define the optical model potential, nuclear level densities and strength of the pre-equilibrium emission. The sensitivity analysis was performed with the set of parameters which reproduces the ENDF/B-VII.0 cross sections. The experimental data were analyzed and both statistical and systematic uncertainties were extracted from almost 30 selected experiments. Then, the Bayesian code KALMAN was used to combine the sensitivity analysis and the experiments to obtain the evaluated covariance matrices.

  16. Re/Os cosmochronometer: measurement of neutron cross sections

    International Nuclear Information System (INIS)

    Mosconi, M.

    2007-01-01

    This experimental work is devoted to the improved assessment of the Re/Os cosmochronometer. The dating technique is based on the decay of 187 Re (t 1/2 =41.2 Gyr) into 187 Os and determines the age of the universe by the time of onset of nucleosynthesis. The nucleosynthesis mechanisms, which are responsible for the 187 Re/ 187 Os pair, provide the possibility to identify the radiogenic fraction of 187 Os exclusively by nuclear physics considerations. Apart from its radiogenic component, 187 Os can be synthesized otherwise only by the s process, which means that this missing fraction can be reliably determined and subtracted by proper s-process modeling. On the other hand, 187 Re is almost completely produced by the r process. The only information needed for the interpretation as a cosmic clock is the production rate of 187 Re as a function of time. The accuracy of the s-process calculations that are needed to determine the nucleosynthetic abundance of 187 Os depends on the quality of the neutron capture cross sections averaged over the thermal neutron spectrum at the s-process sites. Laboratory measurements of these cross sections have to be corrected for the effect of nuclear levels, which can be significantly populated at the high stellar temperatures during the s process. The neutron capture cross sections of 186 Os, 187 Os and 188 Os have been measured at the CERN n TOF facility in the range between 0.7 eV and 1 MeV. From these data, Maxwellian averaged cross sections have been determined for thermal energies from 5 to 100 keV with an accuracy around 4%, 3%, and 5% for 186 Os, 187 Os, and 188 Os, respectively. Since, the first excited state in 187 Os occurs at 9.75 keV, the cross section of this isotope requires a substantial correction for thermal population of low lying nuclear levels. This effect has been evaluated on the basis of resonance data derived in the (n, γ) experiments and by an improved measurements of the inelastic scattering cross section for

  17. Measurement of the Proton-Air Cross Section at root s=57 TeV with the Pierre Auger Observatory

    NARCIS (Netherlands)

    Abreu, P.; Aglietta, M.; Ahn, E. J.; Albuquerque, I. F. M.; Allard, D.; Allekotte, I.; Allen, J.; Allison, P.; Almeda, A.; Alvarez Castillo, J.; Alvarez-Muniz, J.; Ambrosio, M.; Aminaei, A.; Anchordoqui, L.; Andringa, S.; Anticic, T.; Aramo, C.; Arganda, E.; Arqueros, F.; Asorey, H.; Assis, P.; Aublin, J.; Ave, M.; Avenier, M.; Avila, G.; Baecker, T.; Balzer, M.; Barber, K. B.; Barbosa, A. F.; Bardenet, R.; Barroso, S. L. C.; Baughman, B.; Baeuml, J.; Beatty, J. J.; Becker, B. R.; Becker, K. H.; Belletoile, A.; Bellido, J. A.; BenZvi, S.; Berat, C.; Bertou, X.; Biermann, P. L.; Billoir, P.; Blanco, F.; Blanco, M.; Bleve, C.; Bluemer, H.; Bohacova, M.; Boncioli, D.; Bonifazi, C.; Bonino, R.; Borodai, N.; Brack, J.; Brogueira, P.; Brown, W. C.; Bruijn, R.; Buchholz, P.; Bueno, A.; Burton, R. E.; Caballero-Mora, K. S.; Caramete, L.; Caruso, R.; Castellina, A.; Catalano, O.; Cataldi, G.; Cazon, L.; Cester, R.; Chauvin, J.; Cheng, S. H.; Chiavassa, A.; Chinellato, J. A.; Diaz, J. Chirinos; Chudoba, J.; Clay, R. W.; Coluccia, M. R.; Conceicao, R.; Contreras, F.; Cook, H.; Cooper, M. J.; Coppens, J.; Cordier, A.; Coutu, S.; Covault, C. E.; Creusot, A.; Criss, A.; Cronin, J.; Curutiu, A.; Dagoret-Campagne, S.; Dallier, R.; Dasso, S.; Daumiller, K.; Dawson, B. R.; de Almeida, R. M.; De Domenico, M.; De Donato, C.; de Jong, S. J.; De La Vega, G.; de Mello Junior, W. J. M.; de Mello Neto, J. R. T.; De Mitri, I.; de Souza, V.; de Vries, K. D.; Decerprit, G.; del Peral, L.; del Rio, M.; Deligny, O.; Dembinski, H.; Dhital, N.; Di Giulio, C.; Diaz Castro, M. L.; Diep, P. N.; Dobrigkeit, C.; Docters, W.; D'Olivo, J. C.; Dong, P. N.; Dorofeev, A.; dos Anjos, J. C.; Dova, M. T.; D'Urso, D.; Dutan, I.; Ebr, J.; Engel, R.; Erdmann, M.; Escobar, C. O.; Espadanal, J.; Etchegoyen, A.; San Luis, P. Facal; Fajardo Tapia, I.; Falcke, H.; Farrar, G.; Fauth, A. C.; Fazzini, N.; Ferguson, A. P.; Ferrero, A.; Fick, B.; Filevich, A.; Filipcic, A.; Fliescher, S.; Fracchiolla, C. E.; Fraenkel, E. D.; Froehlich, U.; Fuchs, B.; Gaior, R.; Gamarra, R. F.; Gambetta, S.; Garcia, B.; Garcia-Gamez, D.; Garcia-Pinto, D.; Gascon, A.; Gemmeke, H.; Gesterling, K.; Ghia, P. L.; Giaccari, U.; Giller, M.; Glass, H.; Gold, M. S.; Golup, G.; Gomez Albarracin, F.; Gomez Berisso, M.; Goncalves, P.; Gonzalez, D.; Gonzalez, J. G.; Gookin, B.; Gora, D.; Gorgi, A.; Gouffon, P.; Gozzini, S. R.; Grashorn, E.; Grebe, S.; Griffith, N.; Grigat, M.; Grillo, A. F.; Guardincerri, Y.; Guarino, F.; Guedes, G. P.; Guzman, A.; Hague, J. D.; Hansen, P.; Harari, D.; Harmsma, S.; Harrison, T. A.; Harton, J. L.; Haungs, A.; Hebbeker, T.; Heck, D.; Herve, A. E.; Hojvat, C.; Hollon, N.; Holmes, V. C.; Homola, P.; Horandel, J. R.; Horneffer, A.; Horvath, P.; Hrabovsky, M.; Huege, T.; Insolia, A.; Ionita, F.; Italiano, A.; Jarne, C.; Jiraskova, S.; Josebachuili, M.; Kadija, K.; Kampert, K. H.; Karhan, P.; Kasper, P.; Kegl, B.; Keilhauer, B.; Keivani, A.; Kelley, J. L.; Kemp, E.; Kieckhafer, R. M.; Klages, H. O.; Kleifges, M.; Kleinfeller, J.; Knapp, J.; Koang, D-H.; Kotera, K.; Krohm, N.; Kroemer, O.; Kruppke-Hansen, D.; Kuehn, F.; Kuempel, D.; Kulbartz, J. K.; Kunka, N.; La Rosa, G.; Lachaud, C.; Lauer, R.; Lautridou, P.; Le Coz, S.; Leao, M. S. A. B.; Lebrun, D.; Lebrun, P.; Leigui de Oliveira, M. A.; Lemiere, A.; Letessier-Selvon, A.; Lhenry-Yvon, I.; Link, K.; Lopez, R.; Lopez Agueera, A.; Louedec, K.; Lozano Bahilo, J.; Lu, L.; Lucero, A.; Ludwig, M.; Lyberis, H.; Macolino, C.; Maldera, S.; Mandat, D.; Mantsch, P.; Mariazzi, A. G.; Marin, J.; Marin, V.; Maris, I. C.; Falcon, H. R. Marquez; Marsella, G.; Martello, D.; Martinez, H.; Martinez Bravo, O.; Mathes, H. J.; Matthews, J.; Matthews, J. A. J.; Matthiae, G.; Maurizio, D.; Mazur, P. O.; Medina-Tanco, G.; Melissas, M.; Melo, D.; Menichetti, E.; Menshikov, A.; Mertsch, P.; Meurer, C.; Micanovic, S.; Micheletti, M. I.; Miller, W.; Miramonti, L.; Molina-Bueno, L.; Mollerach, S.; Monasor, M.; Ragaigne, D. Monnier; Montanet, F.; Morales, B.; Morello, C.; Moreno, E.; Moreno, J. C.; Morris, C.; Mostafa, M.; Moura, C. A.; Mueller, S.; Muller, M. A.; Mueller, G.; Muenchmeyer, M.; Mussa, R.; Navarra, G.; Navarro, J. L.; Navas, S.; Necesal, P.; Nellen, L.; Nelles, A.; Neuser, J.; Nhung, P. T.; Niemietz, L.; Nierstenhoefer, N.; Nitz, D.; Nosek, D.; Nozka, L.; Nyklicek, M.; Oehlschlaeger, J.; Olinto, A.; Olmos-Gilbaja, V. M.; Ortiz, M.; Pacheco, N.; Selmi-Dei, D. Pakk; Palatka, M.; Pallotta, J.; Palmieri, N.; Parente, G.; Parizot, E.; Parra, A.; Parsons, R. D.; Pastor, S.; Paul, T.; Pech, M.; Pekala, J.; Pelayo, R.; Pepe, I. M.; Perrone, L.; Pesce, R.; Petermann, E.; Petrera, S.; Petrinca, P.; Petrolini, A.; Petrov, Y.; Petrovic, J.; Pfendner, C.; Phan, N.; Piegaia, R.; Pierog, T.; Pieroni, P.; Pimenta, M.

    2012-01-01

    We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail.

  18. Resistivity of epitaxial copper nanolines with trapezoidal cross-section

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Zonghuan; Frey, David M.; Merkh, Thomas; Lord, Robert; Washington, Morris A.; Lu, Toh-Ming

    2016-01-29

    The resistivity of epitaxial Cu nanolines with line width ranging from 20 to 180 nm and line height from 40 to 50 nm was measured using a four-point probe technique. The Cu nanolines were fabricated using ebeam lithography with a polymethyl methacrylate bilayer resist system for improved line edge smoothness. The cross-section profile of the lines was examined using the focused ion beam milling technique. The results indicate that the cross-section should be more accurately described as trapezoidal rather than as rectangular. Using the trapezoidal profile, the electrical resistivity was calculated from the measured resistance data. Modeling based on the Fuchs–Sondheimer (FS) theory using the trapezoidal profile was also carried out. The results were compared with the experimentally calculated resistivity data. For Cu lines with line width less than 30 nm, the measured resistivity was shown to be up to 20% higher than the value predicted by the FS theory. Further examination of Cu lines using atomic force microscopy and scanning electron microscopy was conducted to extract the surface roughness and line edge roughness information. Their contribution to the resistivity increase was estimated to be only up to 3% for the Cu nanolines fabricated, which did not significantly contribute to the overall resistivity for Cu lines with line width less than 30 nm. Other possible factors affecting the resistivity of the Cu nanolines were also discussed, including the oxide formation on the surface of the Cu lines. - Highlights: • Epitaxial copper nanolines were fabricated using ebeam lithography. • The effect of line cross-section profiles on electrical resistivity was studied. • Trapezoidal cross−section gives better resistivity estimation for lines down to 20 nm. • Impact of surface roughness and line edge roughness to resistivity is small. • Oxidization layer has an effect on the resistivity increase.

  19. Resistivity of epitaxial copper nanolines with trapezoidal cross-section

    International Nuclear Information System (INIS)

    Lu, Zonghuan; Frey, David M.; Merkh, Thomas; Lord, Robert; Washington, Morris A.; Lu, Toh-Ming

    2016-01-01

    The resistivity of epitaxial Cu nanolines with line width ranging from 20 to 180 nm and line height from 40 to 50 nm was measured using a four-point probe technique. The Cu nanolines were fabricated using ebeam lithography with a polymethyl methacrylate bilayer resist system for improved line edge smoothness. The cross-section profile of the lines was examined using the focused ion beam milling technique. The results indicate that the cross-section should be more accurately described as trapezoidal rather than as rectangular. Using the trapezoidal profile, the electrical resistivity was calculated from the measured resistance data. Modeling based on the Fuchs–Sondheimer (FS) theory using the trapezoidal profile was also carried out. The results were compared with the experimentally calculated resistivity data. For Cu lines with line width less than 30 nm, the measured resistivity was shown to be up to 20% higher than the value predicted by the FS theory. Further examination of Cu lines using atomic force microscopy and scanning electron microscopy was conducted to extract the surface roughness and line edge roughness information. Their contribution to the resistivity increase was estimated to be only up to 3% for the Cu nanolines fabricated, which did not significantly contribute to the overall resistivity for Cu lines with line width less than 30 nm. Other possible factors affecting the resistivity of the Cu nanolines were also discussed, including the oxide formation on the surface of the Cu lines. - Highlights: • Epitaxial copper nanolines were fabricated using ebeam lithography. • The effect of line cross-section profiles on electrical resistivity was studied. • Trapezoidal cross−section gives better resistivity estimation for lines down to 20 nm. • Impact of surface roughness and line edge roughness to resistivity is small. • Oxidization layer has an effect on the resistivity increase.

  20. Klein-Nishina electronic cross-section, Compton cross sections, and buildup factor of wax for radiation shielding and protection.

    Science.gov (United States)

    Alenezi, Manar; Stinson, Kayla R; Maqbool, Muhammad; Bolus, Norman

    2018-01-05

    Klein-Nishina scattering cross-sections, Compton scattering, mass attenuation and energy transfer cross-sections, linear attenuation coefficient and buildup factor of paraffin wax are calculated using 0.662 MeV, 0.835 MeV, 1.17 MeV and 1.33 MeV γ-rays. The mentioned γ-rays were obtained from Cs137, Mn54 and Co60 radioisotopes. Gamma rays obtained from these radioisotopes were passed through circular shaped wax slices and allowed to fall on a NaI detector. The thickness of wax slices were 0.33 cm to 2.9 cm with 6 cm diameter. Lead collimator of 1 cm diameter hole in the middle was used to obtain a collimated beam for narrow beam geometry. Broad beam geometry was used by removing collimator, to investigate buildup factor. Results show that Klein-Nishina electronic cross-section, Compton mass attenuation coefficient and Compton energy transfer coefficient all decrease with increasing photon energy. Slope of the thickness vs counts graph for narrow beam geometry gives linear attenuation coefficient μ = 0.0532 cm-1 for 1.17 MeV beam and μ = 0.0419 cm-1 for 1.33 MeV γ-rays. Variations in buildup factors are observed with increasing thickness of wax for 1.17 MeV and 1.33 MeV beams. © 2018 IOP Publishing Ltd.

  1. From ZZ to ZH : How Low Can These Cross Sections Go or Everybody, Let's Cross Section Limbo!

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Emanuel Alexandre [Stony Brook Univ., NY (United States)

    2009-08-01

    We report on two searches performed at the D0 detector at the Fermi National Laboratory. The first is a search for Z di-boson production with a theoretical cross section of 1.4 pb. The search was performed on 2.6 fb-1 of data and contributed to the first observation of ZZ production at a hadron collider. The second is a search for a low mass Standard Model Higgs in 4.2 fb-1 of data. The Higgs boson is produced in association with a Z boson where the Higgs decays hadronically and the Z decays to two leptons. The ZZ search was performed in both the di-electron and di-muon channels. For the ZH search, we will focus on the muonic decays where we expanded the traditional coverage by considering events in which one of the two muons fails the selection requirement, and is instead reconstructed as an isolated track. We consider Higgs masses between 100 and 150 GeV, with theoretical cross sections ranging from 0.17 to 0.042 pb, and set upper limits on the ZH production cross-section at 95% confidence level.

  2. WHEELSET AXLE WITH THE CAVITY OF UNIFORM CROSS SECTION

    Directory of Open Access Journals (Sweden)

    S. R. Kolesnykov

    2014-10-01

    Full Text Available Purpose. Due to operation in complex loading conditions, the rolling stock wheelsets should provide high reliability, since the train traffic safety largely depends on them. Design and technical condition of wheelsets affect the smoothness, intensity of forces generated by the interaction between the car and track, and the motion resistance. Specificity of the axle operation consists in the fact that it undergoes the bending stresses under loading. These stresses are unevenly distributed along the cross-sectional area, reaching the highest values in the outer fibers and the minimal values in the internal ones. This aspect sets the problem of replacement of the uniform cross section with the hollow cross section. The disadvantages of hollow axle design, which are used at the present time, should include a significant manufacturing complexity of the variable section cavity. The purpose is to develop a modernized design of the wheelset axle. Methodology. A construction of the hollow axle having an inner longitudinal cylindrical through hole of the constant diameter throughout its length was proposed. The item is made of steel seamless tube. The inner surface of the tube is treated by mechanical means to remove the voltage concentrations in the internal longitudinal cylindrical through hole, which has a constant diameter along the entire length of the axle. Findings. Application of this design will facilitate manufacturing of the hollow axle and the machining of the inner longitudinal through hole, while retaining all the use advantages of the hollow axle in the rolling stock wheel pairs. Another use advantage of the hollow axle of this design is the absence of partial heterogeneity of the metal, which is inevitably, occurs during the solid axles blanking. Originality. A new design of the wheelset hollow axle of railway rolling stock was proposed. Practical value. Introduction of the new design simplifying the manufacture and mechanical treatment of

  3. Curves and tables of neutron cross sections in JENDL-3.3

    CERN Document Server

    Nakagawa, T; Shibata, K

    2002-01-01

    Neutron cross sections of 337 nuclides in JENDL-3.3 are presented in figures and tables. In the tables, shown are cross sections at 0.0253 eV and 14 MeV, Maxwellian average cross sections (kT = 0.0253 eV), resonance integrals and fission spectrum average cross sections. The average cross sections calculated with typical reactor spectra are also tabulated. The numbers of delayed and total neutrons per fission are given in figures.

  4. New numerical methods for nuclear cross section processing

    International Nuclear Information System (INIS)

    Ferran, Ghislain

    2014-01-01

    Nuclear data allow to describe how a particle interacts with matter. These data are therefore at the basis of neutron transport and reactor physics calculations. Once measured and evaluated, they are given in libraries as a list of parameters. Before they can be used in neutron transport calculations, processing is required which includes taking into account several physical phenomena. This can be done by several softwares, such as NJOY, which all have the drawback to use old numerical methods derived from the same algorithms. For nuclear safety applications, it is important to rely on independent methods, to have a comparison point and to isolate the effects of the treatment on the final results. Moreover, it is important to properly master processing accuracy during its different steps. The objective of this PhD is then to develop independent numerical methods that can guarantee nuclear data processing within a given precision and to implement them practically, with the creation of the GAIA software. Our first step was the reconstruction of cross sections from the parameters given in libraries, with different approximations of the R-matrix theory. Reconstruction using the general formalism, without any approximation, has also been implemented, which has required the development of a new method to calculate the R-matrix. Tests have been performed on all existing formalisms, including the newest one. They have shown a good agreement between GAIA and NJOY. Reconstruction of angular differential cross sections directly from R-matrix parameters, using the Blatt-Biedenharn formula, has also been implemented and tested. The cross sections we have obtained at this point correspond to a target nucleus at absolute zero temperature. Because of thermal agitation, these cross sections are subject to a Doppler effect that is taken into account by integrating them with Solbrig's kernel. Our second step was then to calculate this integral. First, we have elaborated and

  5. Propionaldehyde infrared cross-sections and band strengths

    International Nuclear Information System (INIS)

    Köroğlu, Batikan; Loparo, Zachary; Nath, Janardan; Peale, Robert E.; Vasu, Subith S.

    2015-01-01

    The use of oxygenated biofuels reduces the greenhouse gas emissions; however, they also result in increased toxic aldehyde by-products, mainly formaldehyde, acetaldehyde, acrolein, and propionaldehyde. These aldehydes are carcinogenic and/or toxic and therefore it is important to understand their formation and destruction pathways in combustion and atmospheric systems. Accurate information about their infrared cross-sections and integrated strengths are crucially needed for development of quantitative detection schemes and modeling tools. Critical to the development of such diagnostics are accurate characterization of the absorption features of these species. In this study, the gas phase infrared spectra of propionaldehyde (also called propanal, CH 3 –CH 2 –CHO), a saturated three carbon aldehyde found in the exhaust emissions of biodiesel or diesel fuels, was studied using high resolution Fourier Transform Infrared (FTIR) spectroscopy over the wavenumber range of 750−3300 cm −1 and at room temperature 295 K. The absorption cross sections of propionaldehyde were recorded at resolutions of 0.08 and 0.096 cm −1 and at seven different pressures (4−33 Torr). The calculated band-strengths were reported and the integrated band intensity results were compared with values taken from the Pacific Northwest National Laboratory (PNNL) database (showing less than 2% discrepancy). The peak positions of the 19 different vibrational bands of propionaldehyde were also compared with previous studies taken at a lower resolution of 1 cm −1 . To the best of our knowledge, the current FTIR measurements provide the first highest resolution infrared cross section data for propionaldehyde. - Highlights: • High resolution IR spectra of propionaldehyde were measured by FTIR spectrometer. • The discrepancy between the present study and PNNL database was less than 2%. • The fundamental vibrational frequencies were reported at high resolution. • The rovibrational Q

  6. Propionaldehyde infrared cross-sections and band strengths

    Science.gov (United States)

    Köroğlu, Batikan; Loparo, Zachary; Nath, Janardan; Peale, Robert E.; Vasu, Subith S.

    2015-02-01

    The use of oxygenated biofuels reduces the greenhouse gas emissions; however, they also result in increased toxic aldehyde by-products, mainly formaldehyde, acetaldehyde, acrolein, and propionaldehyde. These aldehydes are carcinogenic and/or toxic and therefore it is important to understand their formation and destruction pathways in combustion and atmospheric systems. Accurate information about their infrared cross-sections and integrated strengths are crucially needed for development of quantitative detection schemes and modeling tools. Critical to the development of such diagnostics are accurate characterization of the absorption features of these species. In this study, the gas phase infrared spectra of propionaldehyde (also called propanal, CH3-CH2-CHO), a saturated three carbon aldehyde found in the exhaust emissions of biodiesel or diesel fuels, was studied using high resolution Fourier Transform Infrared (FTIR) spectroscopy over the wavenumber range of 750-3300 cm-1 and at room temperature 295 K. The absorption cross sections of propionaldehyde were recorded at resolutions of 0.08 and 0.096 cm-1 and at seven different pressures (4-33 Torr). The calculated band-strengths were reported and the integrated band intensity results were compared with values taken from the Pacific Northwest National Laboratory (PNNL) database (showing less than 2% discrepancy). The peak positions of the 19 different vibrational bands of propionaldehyde were also compared with previous studies taken at a lower resolution of 1 cm-1. To the best of our knowledge, the current FTIR measurements provide the first highest resolution infrared cross section data for propionaldehyde.

  7. Differences between cross-section libraries for neutron dosimetry

    International Nuclear Information System (INIS)

    Tardelli, T.C.; Stecher, L.C.; Coelho, T.S.; Castro, V.A. De; Cavalieri, T.A.; Menzel, F.; Giarola, R.S.; Domingos, D.B.; Yoriyaz, H.

    2013-01-01

    Absorbed dose calculations depend on a consistent set of nuclear data used in simulations in computer codes. Nuclear data are stored in libraries, however, the information available about the differences in dose caused by different libraries are rare. The libraries are processed by a computer system to be able to be used by a radiation transport code. One of the systems capable of processing nuclear data is the NJOY system. The objective of this study is to evaluate the nuclear data libraries for neutrons available in the literature, and to quantify the differences in absorbed dose obtained using the libraries JENDL 4.0, JEFF 3.3.1 and ENDF/B.VII. The absorbed dose calculation was performed on a simple geometric model, as spheres, and in anthropomorphic model of the human body based on the ICRP-110 for neutron transport simulation using the MCNP5 code. The results were compared with literature data. The results obtained with cross sections from the libraries JEFF and ENDF/B.VII have shown to be identical in most cases, except for one case where the difference has exceeded 10%. The results obtained with JENDL library has shown to be considerably different in most cases comparing to other two libraries. Some differences were over 200%. The dose calculations showed differences between the libraries, which is justified by differences in the cross sections. It has been observed that the cross sections values of certain nuclides assume quite different values in different libraries. These differences in turn cause considerable differences in dose calculations. (author)

  8. Noncircular Cross Sections Could Enhance Mixing in Sprays

    Science.gov (United States)

    Bellan, Josette; Abdel-Hameed, Hesham

    2003-01-01

    A computational study has shown that by injecting drops in jets of gas having square, elliptical, triangular, or other noncircular injection cross sections, it should be possible to increase (relative to comparable situations having circular cross section) the entrainment and dispersion of liquid drops. This finding has practical significance for a variety of applications in which it is desirable to increase dispersion of drops. For example, in chemical-process sprays, increased dispersion leads to increases in chemical- reaction rates; in diesel engines, increasing the dispersion of drops of sprayed fuel reduces the production of soot; and in household and paint sprays, increasing the dispersion of drops makes it possible to cover larger surfaces. It has been known for some years that single-phase fluid jets that enter flow fields through noncircular inlets entrain more fluid than do comparable jets entering through circular inlets. The computational study reported here was directed in part toward determining whether and how this superior mixing characteristic of noncircular single phase jets translates to a similar benefit in cases of two-phase jets (that is, sprays). The study involved direct numerical simulations of single- and two-phase free jets with circular, elliptical, rectangular, square, and triangular inlet cross sections. The two-phase jets consisted of gas laden with liquid drops randomly injected at the inlets. To address the more interesting case of evaporating drops, the carrier gas in the jets was specified to be initially unvitiated by the vapor of the liquid chemical species and the initial temperature of the drops was chosen to be smaller than that of the gas. The mathematical model used in the study was constructed from the conservation equations for the two-phase flow and included complete couplings of mass, momentum, and energy based on thermodynamically self-consistent specification of the enthalpy, internal energy, and latent heat of

  9. Hadronic Production of Ψ(2S) Cross section and Polarization

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Kwangzoo [Carnegie Mellon Univ., Pittsburgh, PA (United States)

    2008-05-01

    The hadronic production cross section and the polarization of Ψ(2S) meson are measured by using the data from p$\\bar{p}$ collisions at √s = 1.96 TeV collected by the Collider Detector at Fermilab. The datasets used correspond to integrated luminosity of 1.1 fb-1 and 800 pb-1, respectively. The decay Ψ(2S) → μ+μ- is used to reconstruct Ψ(2S) mesons in the rapidity range |y(Ψ(2S))| < 0.6. The coverage of the pT range is 2.0 GeV/c ≤ pT (Ψ(2S)) < 30 GeV/c for the cross section analysis and pT ≥ 5 GeV/c for the polarization analysis. For events with pT (Ψ(2S)) > 2 GeV/c the integrated inclusive cross section multiplied by the branching ratio for dimuon decay is 3.17 ± 0.04 ± 0.28 nb . This result agrees with the CDF Run I measurement considering the increased center-of-mass energy from 1.8 TeV to 1.96 TeV. The polarization of the promptly produced Ψ(2S) mesons is found to be increasingly longitudinal as pT increases from 5 GeV/c to 30 GeV/c. The result is compared to contemporary theory models.

  10. Neutron displacement damage cross sections for SiC

    International Nuclear Information System (INIS)

    Huang Hanchen; Ghoniem, N.

    1993-01-01

    Calculations of neutron displacement damage cross sections for SiC are presented. We use Biersack and Haggmark's empirical formula in constructing the electronic stopping power, which combines Lindhard's model at low PKA energies and Bethe-Bloch's model at high PKA energies. The electronic stopping power for polyatomic materials is computed on the basis of Bragg's Additivity Rule. A continuous form of the inverse power law potential is used for nuclear scattering. Coupled integro-differential equations for the number of displaced atoms j, caused by PKA i, are then derived. The procedure outlined above gives partial displacement cross sections, displacement cross sections for each specie of the lattice, and for each PKA type. The corresponding damage rates for several fusion and fission neutron spectra are calculated. The stoichiometry of the irradiated material is investigated by finding the ratio of displacements among various atomic species. The role of each specie in displacing atoms is also investigated by calculating the fraction of displacements caused by each PKA type. The study shows that neutron displacement damage rates of SiC in typical magnetic fusion reactor first walls will be ∝10-15 dpa MW -1 m 2 ; in typical lead-protected inertial confinement fusion reactor first walls they will be ∝15-20 dpa MW -1 m 2 . For fission spectra, we find that the neutron displacement damage rate of SiC is ∝74 dpa per 10 27 n/m 2 in FFTF, ∝39 dpa per 10 27 n/m 2 in HFIR, and 25 dpa per 10 27 n/m 2 in NRU. Approximately 80% of displacement atoms are shown to be of the carbon-type. (orig.)

  11. Mass Spectra and Ion Collision Cross Sections of Hemoglobin

    Science.gov (United States)

    Kang, Yang; Terrier, Peran; Douglas, D. J.

    2011-02-01

    Mass spectra of commercially obtained hemoglobin (Hb) show higher levels of monomer and dimer ions, heme-deficient dimer ions, and apo-monomer ions than hemoglobin freshly prepared from blood. This has previously been attributed to oxidation of commercial Hb. Further, it has been reported that that dimer ions from commercial bovine Hb have lower collision cross sections than low charge state monomer ions. To investigate these effects further, we have recorded mass spectra of fresh human Hb, commercial human and bovine Hb, fresh human Hb oxidized with H2O2, lyophilized fresh human Hb, fresh human Hb both lyophilized and chemically oxidized, and commercial human Hb oxidized with H2O2. Masses of α-monomer ions of all hemoglobins agree with the masses expected from the sequences within 3 Da or better. Mass spectra of the β chains of commercial Hb and oxidized fresh human Hb show a peak or shoulder on the high mass side, consistent with oxidation of the protein. Both commercial proteins and oxidized fresh human Hb produce heme-deficient dimers with masses 32 Da greater than expected and higher levels of monomer and dimer ions than fresh Hb. Lyophilization or oxidation of Hb both produce higher levels of monomer and dimer ions in mass spectra. Fresh human Hb, commercial human Hb, commercial bovine Hb, and oxidized commercial human Hb all give dimer ions with cross sections greater than monomer ions. Thus, neither oxidation of Hb or the difference in sequence between human and bovine Hb make substantial differences to cross sections of ions.

  12. Theory of neutron resonance cross sections for safety applications

    International Nuclear Information System (INIS)

    Froehner, F.H.

    1992-09-01

    Neutron resonances exert a strong influence on the behaviour of nuclear reactors, especially on their response to the temperature changes accompanying power excursions, and also on the efficiency of shielding materials. The relevant theory of neutron resonance cross sections including the practically important approximations is reviewed, both for the resolved and the unresolved resonance region. Numerical techniques for Doppler broadening of resonances are presented, and the construction of group constants and especially of self-shielding factors for neutronics calculations is outlined. (orig.) [de

  13. Direct photon cross section with conversions at CDF

    OpenAIRE

    CDF collaboration

    2004-01-01

    We present a measurement of the isolated direct photon cross section in p (p) over bar collisions at roots=1.8 TeV and \\eta\\ lt 0.9 using data collected between 1994 and 1995 by the Collider Detector at Fermilab (CDF). The measurement is based on events where the photon converts into an electron-positron pair in the material of the inner detector, resulting in a two track event signature. To remove pi(0)→gammagamma and eta→gammagamma events from the data we use a new background subtraction te...

  14. Artificial Neural Networks For Hadron Hadron Cross-sections

    International Nuclear Information System (INIS)

    ELMashad, M.; ELBakry, M.Y.; Tantawy, M.; Habashy, D.M.

    2011-01-01

    In recent years artificial neural networks (ANN ) have emerged as a mature and viable framework with many applications in various areas. Artificial neural networks theory is sometimes used to refer to a branch of computational science that uses neural networks as models to either simulate or analyze complex phenomena and/or study the principles of operation of neural networks analytically. In this work a model of hadron- hadron collision using the ANN technique is present, the hadron- hadron based ANN model calculates the cross sections of hadron- hadron collision. The results amply demonstrate the feasibility of such new technique in extracting the collision features and prove its effectiveness

  15. Evaluation and calculation of neutron transactinide cross-sections

    International Nuclear Information System (INIS)

    Konshin, V.A.

    1980-01-01

    This paper reviews the state of the art of nuclear theory and its application to the evaluation and calculation of neutron reaction cross sections of transactinium isotopes. In particular, the paper describes the current evaluation of the total files of neutron reaction data for 240 Pu and 241 Pu in the energy range between 10 -5 eV and 15 MeV based on a thorough analysis of available experimental data and on the use of modern theoretical concepts, and the work in progress on the evaluation of the total neutron reaction data file for 242 Pu and 241 Am. (author)

  16. Total cross sections for pion charge exchange on the proton

    Energy Technology Data Exchange (ETDEWEB)

    Breitschopf, J.

    2006-04-28

    This work describes the measurement of total SCX cross sections employing a new 4{pi} scintillation counter to perform transmission measurements in the incident pion energy range from about 38 to 250 MeV. A small 4{pi} detector box consisting of thin plastic scintillators has been constructed. The transmission technique, which was used, relates the number of transmitted charged pions to that of incident beam pions and this way effectively counts events with neutral products. The incoming negative pions were counted by three beam defining counters before they hit a target of very well known size and chemical composition. The target was placed in the box detector which was not sensitive to the neutral particles resulting from the SCX. The total cross section for emerging neutral particles was derived from the comparison of the numbers of the incoming and transmitted charged particles. The total SCX cross section on hydrogen was derived from the transmissions of a CH{sub 2} target, a carbon target and an empty target. For a detailed offline analysis all TDC, QDC and FADC information was recorded in an event by event mode for each triggered beam event. Various corrections had to be applied to the data, such as random correction, the detection of neutrals in the detector, Dalitz decay, pion decay and the radiative pion capture. This measurement covers, as the only experiment, the whole {delta}-resonance and the sp-interference region in one single experimental setup and improves the available data base for the SCX reaction. It is shown that the description of the SCX cross sections is improved if the s-wave amplitudes, that have been fixed essentially by elastic pion-nucleon scattering data, is reduced by (4{+-}1.5)%. The exact value depends on the SCX literature data included and on the parameters of the {delta}{sup 0} Breit-Wigner resonance describing the p{sub 33}-waves. This shows that p-wave as well as s-wave effects should be considered in studies of isospin

  17. Inelastic proton cross-section at 13 TeV

    CERN Document Server

    Myska, Miroslav; The ATLAS collaboration

    2016-01-01

    Poster describes the recent measurement of the inelastic cross-section at 13 TeV with the ATLAS detector, extracted with independent measurements of the rate of inelastic collisions and the LHC luminosity. The result of 79.3 $\\pm$ 2.9 mb has been obtained after extrapolation to the full phase space and is compared with a range of theoretical predictions. In addition, the fraction of diffractive events is measured using two event selections. The low-luminosity data of total integrated luminosity of 60.1 $\\mu b^{-1}$ recorded in June 2016 was used.

  18. Proton radiography, nuclear cross sections and multiple Coulomb scattering

    Energy Technology Data Exchange (ETDEWEB)

    Sjue, Sky K. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-04

    The principles behind proton radiography including multiple Coulomb scattering are discussed for a purely imaginary square well nucleus in the eikonal approximation. It is found that a very crude model can reproduce the angular dependence of the cross sections measured at 24 GeV/c. The largest differences are ~3% for the 4.56 mrad data, and ~4% for the 6.68 mrad data. The prospect of understanding how to model deterministically high-energy proton radiography over a very large range of energies is promising, but it should be tested more thoroughly.

  19. Nuclear fission and neutron-induced fission cross-sections

    CERN Document Server

    James, G D; Michaudon, A; Michaudon, A; Cierjacks, S W; Chrien, R E

    2013-01-01

    Nuclear Fission and Neutron-Induced Fission Cross-Sections is the first volume in a series on Neutron Physics and Nuclear Data in Science and Technology. This volume serves the purpose of providing a thorough description of the many facets of neutron physics in different fields of nuclear applications. This book also attempts to bridge the communication gap between experts involved in the experimental and theoretical studies of nuclear properties and those involved in the technological applications of nuclear data. This publication will be invaluable to those interested in studying nuclear fis

  20. Total cross sections for pion charge exchange on the proton

    International Nuclear Information System (INIS)

    Breitschopf, J.

    2006-01-01

    This work describes the measurement of total SCX cross sections employing a new 4π scintillation counter to perform transmission measurements in the incident pion energy range from about 38 to 250 MeV. A small 4π detector box consisting of thin plastic scintillators has been constructed. The transmission technique, which was used, relates the number of transmitted charged pions to that of incident beam pions and this way effectively counts events with neutral products. The incoming negative pions were counted by three beam defining counters before they hit a target of very well known size and chemical composition. The target was placed in the box detector which was not sensitive to the neutral particles resulting from the SCX. The total cross section for emerging neutral particles was derived from the comparison of the numbers of the incoming and transmitted charged particles. The total SCX cross section on hydrogen was derived from the transmissions of a CH 2 target, a carbon target and an empty target. For a detailed offline analysis all TDC, QDC and FADC information was recorded in an event by event mode for each triggered beam event. Various corrections had to be applied to the data, such as random correction, the detection of neutrals in the detector, Dalitz decay, pion decay and the radiative pion capture. This measurement covers, as the only experiment, the whole Δ-resonance and the sp-interference region in one single experimental setup and improves the available data base for the SCX reaction. It is shown that the description of the SCX cross sections is improved if the s-wave amplitudes, that have been fixed essentially by elastic pion-nucleon scattering data, is reduced by (4±1.5)%. The exact value depends on the SCX literature data included and on the parameters of the Δ 0 Breit-Wigner resonance describing the p 33 -waves. This shows that p-wave as well as s-wave effects should be considered in studies of isospin symmetry breaking. Interestingly

  1. Covariances for the 56Fe radiation damage cross sections

    Directory of Open Access Journals (Sweden)

    Simakov Stanislav P.

    2017-01-01

    Full Text Available The energy-energy and reaction-reaction covariance matrices were calculated for the n + 56Fe damage cross-sections by Total Monte Carlo method using the TENDL-2013 random files. They were represented in the ENDF-6 format and added to the unperturbed evaluation file. The uncertainties for the spectrum averaged radiation quantities in the representative fission, fusion and spallation facilities were first time assessed as 5–25%. Additional 5 to 20% have to be added to the atom displacement rate uncertainties to account for accuracy of the primary defects simulation in materials. The reaction-reaction correlation were shown to be 1% or less.

  2. Measurement of Beauty Particle Lifetimes and Hadroproduction Cross-Section

    CERN Multimedia

    2002-01-01

    We propose an experimental search for beauty particles produced in fixed target hadronic interactions. The essential feature of the proposed experimental technique is the use of two specially designed pieces of hardware~-~a high precision ``decay detector'' and a fast secondary vertex trigger processor. If these devices perform to our expectations, we should be able to obtain sufficient data sample to address several important physics issues, including measurements of the lifetimes of charged and neutral B~mesons, the B~hadroproduction cross-section, and possibly B$^0$- $ \\bar{B} ^0 $ mixing.

  3. Neutron cross section standards evaluations for ENDF/B-VI

    International Nuclear Information System (INIS)

    Carlson, A.D.; Poenitz, W.P.; Hale, G.M.; Peelle, R.W.

    1985-01-01

    The neutron cross section standards are now being evaluated as the initial phase in the development of the new ENDF/B-VI file. These standards evaluations are following a somewhat different process compared with that used for earlier versions of ENDF. The primary effort is concentrated on a simultaneous evaluation using a generalized least squares program, R-matrix evaluations, and a procedure for combining the results of these evaluations. The ENDF/B-VI standards evaluation procedure is outlined, and preliminary simultaneous evaluation and R-matrix results are presented. 16 refs., 7 figs

  4. SCAMPI: A code package for cross-section processing

    Energy Technology Data Exchange (ETDEWEB)

    Parks, C.V.; Petrie, L.M.; Bowman, S.M.; Broadhead, B.L.; Greene, N.M.; White, J.E.

    1996-04-01

    The SCAMPI code package consists of a set of SCALE and AMPX modules that have been assembled to facilitate user needs for preparation of problem-specific, multigroup cross-section libraries. The function of each module contained in the SCANTI code package is discussed, along with illustrations of their use in practical analyses. Ideas are presented for future work that can enable one-step processing from a fine-group, problem-independent library to a broad-group, problem-specific library ready for a shielding analysis.

  5. Scaling of cross sections in ion-atom collisions

    International Nuclear Information System (INIS)

    Differential electron emission at 15 degrees is investigated for 50-500 keV/amu hydrogen impacting on He and H targets. From hydrogen particles (H, H + , H 2 + , H 3 + ) ratios of cross sections relative to proton impact data, it is shown how bound projectile electrons influence the differential electron emission and where different ionization mechanisms are important. It is demonstrated that the H 2 + and H 3 + molecular ions interact as though they are composed of independent nuclei with the appropriate number of bound electrons, the electronic structure of the components appearing to be unimportant

  6. Estimation of the Human Absorption Cross Section Via Reverberation Models

    DEFF Research Database (Denmark)

    Steinböck, Gerhard; Pedersen, Troels; Fleury, Bernard Henri

    2018-01-01

    and compare the obtained results to those of Sabine's model. We find that the absorption by persons is large enough to be measured with a wideband channel sounder and that estimates of the human absorption cross section differ for the two models. The obtained values are comparable to values reported...... in the literature. We also suggest the use of controlled environments with low average absorption coefficients to obtain more reliable estimates. The obtained values can be used to predict the change of reverberation time with persons in the propagation environment. This allows prediction of channel characteristics...... relevant in communication systems, e.g. path loss and rms delay spread, for various population densities....

  7. Photodetachment cross sections for He-(4P0)

    International Nuclear Information System (INIS)

    Compton, R.N.; Alton, G.D.; Pegg, D.J.

    1980-01-01

    The first measurements are reported of photodetachment cross sections for He - (formed through charge exchange of He + with Ca vapor) over the photon energy range from 1.77 to 2.75 eV. The energies of autodetached electrons from the metastable He - beam have also been determined for the first time. The autodetached electron energy agrees within experimental error (+-0.25 eV) with the known 1s2s2p) 4 P 0 He - energy level. This taken with measurements for the lifetime of He - infers that charge exchange of He + with Ca vapor produces 4 P 0 He -

  8. Status of multigroup cross-section data for shielding applications

    International Nuclear Information System (INIS)

    Roussin, R.W.; Maskewitz, B.F.; Trubey, D.K.

    1983-01-01

    Multigroup cross-section libraries for shielding applications in formats for direct use in discrete ordinates or Monte Carlo codes have long been a part of the Data Library Collection (DLC) of the Radiation Shielding Information Center (RSIC). In recent years libraries in more flexible and comprehensive formats, which allow the user to derive his own problem-dependent sets, have been added to the collection. The current status of both types is described, as well as projections for adding data libraries based on ENDF/B-V

  9. Theory of neutron resonance cross sections for safety applications

    International Nuclear Information System (INIS)

    Froehner, F.H.

    1993-01-01

    Neutron resonances exert a strong influence on the behaviour of nuclear reactors, especially on their response to the temperature changes accompanying power excursions, and also on the efficiency of shielding materials. The relevant theory of neutron resonance cross sections including the practically important approximations is reviewed, both for the resolved and the unresolved resonance region. Numerical techniques for Doppler broadening of resonance are presented, and the construction of group constants and especially of self-shielding factors for neutronics calculations is outlined. (author). 75 refs, 14 figs, 3 tabs

  10. Market Skewness Risk and the Cross Section of Stock Returns

    DEFF Research Database (Denmark)

    Young Chang, Bo; Christoffersen, Peter F.; Jacobs, Kris

    2013-01-01

    The cross section of stock returns has substantial exposure to risk captured by higher moments of market returns. We estimate these moments from daily Standard & Poor's 500 index option data. The resulting time series of factors are genuinely conditional and forward-looking. Stocks with high...... exposure to innovations in implied market skewness exhibit low returns on average. The results are robust to various permutations of the empirical setup. The market skewness risk premium is statistically and economically significant and cannot be explained by other common risk factors such as the market...... excess return or the size, book-to-market, momentum, and market volatility factors, or by firm characteristics....

  11. Two-electron photoionization cross sections at high energies

    International Nuclear Information System (INIS)

    Amusia, M.Ya.; Krivec, R.; Mandelzweig, V.B.

    2003-01-01

    Double and single electron photoionization cross sections and their ratios at high and ultra-relativistic energies are calculated for H - , He and helium-like ions in ground and excited states including triplet states. The ratios contain shake-off and quasi-free terms. A high precision non-variational wave function is used. The quasi-free mechanism increases the ratios impressively: for He we get 0.0762 instead of 0.0164 in the non-relativistic case. Ratios are inversely proportional to Z 2 , with a factor increasing from 0.094 in the nonrelativistic to 0.595 in the ultra-relativistic limit. (author)

  12. Cross-sectional investigation of HEMS activities in Europe

    DEFF Research Database (Denmark)

    Di Bartolomeo, Stefano; Gava, Paolo; Truhlář, Anatolij

    2014-01-01

    .000 to 4.500.000. Of 158 requested primary missions, 62 (0.82 per base) resulted in landing. Cardiac aetiology (36%) and trauma (36%) prevailed, mostly of life-threatening severity (43%, 0.64 per mission). Had HEMS been not dispatched, patients would have been attended by another physician in 67% of cases...... and limits the generalizability of the results. Fortunately, because of its cross-sectional characteristics and the handy availability of the web platform, the study is easily repeatable with an enhanced network....

  13. Neutron cross-section determination in geological samples (U)

    International Nuclear Information System (INIS)

    Harris, J.M.; McDaniel, P.J.

    1982-01-01

    The Prompt Gamma Neutron Activation Analysis (PGAA) technique yields elemental composition data which can be used to calculate the macroscopic cross section for any sample. The Small Sample Reactivity Measurements (SSRM) technique yields the macroscopic thermal absorption directly. Experimentally, PGAA is somewhat more difficult because of the calibration and data handling than is SSRM. However, SSRM requires a mathematical model of the reactor which means a rather complicated analysis. Once the model and calibration are completed, data analysis is routine. The SSRM technique is production oriented. 9 figures

  14. Application of backpack Lidar to geological cross-section measurement

    Science.gov (United States)

    Lin, Jingyu; Wang, Ran; Xiao, Zhouxuan; Li, Lu; Yao, Weihua; Han, Wei; Zhao, Baolin

    2017-11-01

    As the traditional geological cross section measurement, the artificial traverse method was recently substituted by using point coordinates data. However, it is still the crux of the matter that how to acquire the high-precision point coordinates data quickly and economically. Thereby, the backpack Lidar is presented on the premise of the principle of using point coordinates in this issue. Undoubtedly, Lidar technique, one of booming and international active remote sensing techniques, is a powerful tool in obtaining precise topographic information, high-precision 3-D coordinates and building a real 3-D model. With field practice and date processing indoors, it is essentially accomplished that geological sections maps could be generated simply, accurately and automatically in the support of relevant software such as ArcGIS and LiDAR360.

  15. Association between maternal death and cesarean section in Latin America: A systematic literature review.

    Science.gov (United States)

    Fahmy, Walid Makin; Crispim, Cibele Aparecida; Cliffe, Susan

    2018-04-01

    it is critically important to explore a possible relationship between cesarean section and maternal mortality in Latin America, where the highest cesarean section rates in the world are found. Our aim was to conduct a systematic literature review on the relationship between maternal death and caesarean section in Latin America. we undertook a systematic review through six electronic databases. Studies that reported any association analysis between maternal mortality and the mode of delivery in Latin America were included. Papers that fulfilled the inclusion criteria were then read fully, and a quality assessment was conducted with the PROMPT tool. seven articles were identified for final analysis, all of which were observational studies. Most of the studies were retrospective (6) and one was prospective. Of the retrospective studies, 3 were case control and 3 were cross-sectional. Most of the publications on this topic suggest that there may be an increased risk of maternal mortality with cesarean section compared with vaginal birth (odds ratio ranging from 1.6 to 7.08). However, it is evident that there is a lack of studies with this subject, especially those that take into account the differences in risk between women delivered by cesarean section or by vaginal birth. most of the articles showed that there may be an increased risk of maternal mortality with cesarean section compared with vaginal birth. However, it is clear that there is a limited number of studies published on this issue. Additional studies with a better methodological design should be conducted. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Neutrino-nucleon cross section measurements in NOMAD

    CERN Document Server

    Wu, Qun

    2006-01-01

    The NOMAD (Neutrino Oscillation MAgnetic Detector) experiment, using the SPS (Super Proton Syncrotron) neutrino beam (1 GeV < E [nu] < 200 GeV) at CERN (European Organization for Nuclear Research), has collected more than 1.7 million neutrino induced charged and neutral current (CC and NC) events. This data is the largest high resolution neutrino nucleon scattering data to date and is ideal for precision measurements and searches in neutrino-physics. This thesis presents the precise measurement of the inclusive neutrino CC cross section in 2.5 GeV < E [nu] < 150 GeV region. The linear dependence of the inclusive CC cross section ([Special characters omitted.] ) versus the incoming neutrino energy ( E [nu] ) is observed in the high energy region of 30 GeV < E [nu] < 150 GeV. Especially, the measurement in 2.5 GeV < E [nu] < 30 GeV region provides the first precise determination of [Special characters omitted.] . The significant deviation from the linear dependence for [Special character...

  17. High order effects in cross section sensitivity analysis

    International Nuclear Information System (INIS)

    Greenspan, E.; Karni, Y.; Gilai, D.

    1978-01-01

    Two types of high order effects associated with perturbations in the flux shape are considered: Spectral Fine Structure Effects (SFSE) and non-linearity between changes in performance parameters and data uncertainties. SFSE are investigated in Part I using a simple single resonance model. Results obtained for each of the resolved and for representative unresolved resonances of 238 U in a ZPR-6/7 like environment indicate that SFSE can have a significant contribution to the sensitivity of group constants to resonance parameters. Methods to account for SFSE both for the propagation of uncertainties and for the adjustment of nuclear data are discussed. A Second Order Sensitivity Theory (SOST) is presented, and its accuracy relative to that of the first order sensitivity theory and of the direct substitution method is investigated in Part II. The investigation is done for the non-linear problem of the effect of changes in the 297 keV sodium minimum cross section on the transport of neutrons in a deep-penetration problem. It is found that the SOST provides a satisfactory accuracy for cross section uncertainty analysis. For the same degree of accuracy, the SOST can be significantly more efficient than the direct substitution method

  18. Neutron cross sections in the unresolved resonance region

    International Nuclear Information System (INIS)

    Janeva, N.; Lukyanov, A.; Koyumdjieva, N.; Volev, K.

    2005-01-01

    In this work a development of the characteristic function model, created to reveal the resonance cross section structure in the unresolved resonance region is presented. The main advantage of this model is the calculation of resonance averaged self-shielding factors analytically. To determine average values of the cross sections and their functionals the function of joint statistical distribution of the R-matrix real and imaginary parts should be used. The characteristic function of such distribution is determined and the resonance ladder for the unresolved region is optimized to calculate the group averaged functionals in the same way as it is in the resolved resonance region. The main advantage of this model is the calculation of resonance averaged self-shielding factors analytically. The neutron width energy dependence leads to some deformation in the shape of resonances. This deformation is most apparent near the inelastic scattering threshold. For the case when the inelastic channel momentum is zero we present the formula for level shape bellow and over the inelastic threshold and the calculated resonance deformation in dependence of the position of the resonance in respect to the threshold. (authors)

  19. Neutron cross section standards and instrumentation. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Wasson, O.A.

    1993-07-01

    The objective of this interagency program is to provide accurate neutron interaction measurements for the US Department of Energy nuclear programs which include waste disposal, fusion, safeguards, defense, fission, and personnel protection. These measurements are also useful to other energy programs which indirectly use the unique properties of the neutron for diagnostic and analytical purposes. The work includes the measurement of reference cross sections and related neutron data employing unique facilities and capabilities at NIST and other laboratories as required; leadership and participation in international intercomparisons and collaborations; the preservation of standard reference deposits and the development of improved neutron detectors and measurement methods. A related and essential element of the program is critical evaluation of neutron interaction data including international coordinations. Data testing of critical data for important applications is included. The program is jointly supported by the Department of Energy and the National Institute of Standards and Technology. This report from the National Institute of Standards and Technology contains a summary of the accomplishments of the Neutron Cross Section Standards and Instrumentation Project during the third year of this three-year interagency agreement. The proposed program and required budget for the following three years are also presented. The program continues the shifts in priority instituted in order to broaden the program base.

  20. Neutron cross section standards and instrumentation. Annual report

    International Nuclear Information System (INIS)

    Wasson, O.A.

    1993-01-01

    The objective of this interagency program is to provide accurate neutron interaction measurements for the US Department of Energy nuclear programs which include waste disposal, fusion, safeguards, defense, fission, and personnel protection. These measurements are also useful to other energy programs which indirectly use the unique properties of the neutron for diagnostic and analytical purposes. The work includes the measurement of reference cross sections and related neutron data employing unique facilities and capabilities at NIST and other laboratories as required; leadership and participation in international intercomparisons and collaborations; the preservation of standard reference deposits and the development of improved neutron detectors and measurement methods. A related and essential element of the program is critical evaluation of neutron interaction data including international coordinations. Data testing of critical data for important applications is included. The program is jointly supported by the Department of Energy and the National Institute of Standards and Technology. This report from the National Institute of Standards and Technology contains a summary of the accomplishments of the Neutron Cross Section Standards and Instrumentation Project during the third year of this three-year interagency agreement. The proposed program and required budget for the following three years are also presented. The program continues the shifts in priority instituted in order to broaden the program base

  1. Cross Sectional Attitudes of Public Sculpture Matrix in Southwestern Nigeria

    Directory of Open Access Journals (Sweden)

    Moses Akintunde Akintonde

    2016-06-01

    Full Text Available Public outdoor sculpture practice in the Southwestern Nigeria entails different types of attitudes. These attitudes are discernable from the stage of commissioning of work, its conceptualization to the display and uses in the public sphere generated diverse fundamental, constant technical issues. Some are explicitly alluring while others are absurd, fleeting and injurious to the practice. However, whatever attitude advanced in the public outdoor sculpture practice, it has not been discussed cross sectionally. The inadequate scholarship attention on the attitudinal issues in outdoor sculpture certainly created art historical gap apt to make the study of contemporary Nigeria art incoherent. Apparently, attitudinal studies certainly involve psychological measurement - a type of instrument that does not required descriptive survey. For this reason, the study was based on qualitative methods. The study categorised various attitudes in outdoor sculpture practice in the studied area into pre-unveiling, unveiling and post unveiling stages and critically examined them. Some attitudes in the practice of the art were observed to be stimulant for advancement; invariably others are clearly incongruous to the spirit of typical Yoruba societal value orientation in orderliness, therefore degrading and detrimental to the development of the outdoor sculpture in the public sphere.Keywords: Art patron; cross sectional attitude; outdoor sculpture; post-unveiling; pre-unveiling; public art; Southwestern Nigeria; unveiling.

  2. Neutron Scattering Differential Cross Sections for 12C

    Science.gov (United States)

    Byrd, Stephen T.; Hicks, S. F.; Nickel, M. T.; Block, S. G.; Peters, E. E.; Ramirez, A. P. D.; Mukhopadhyay, S.; McEllistrem, M. T.; Yates, S. W.; Vanhoy, J. R.

    2016-09-01

    Because of the prevalence of its use in the nuclear energy industry and for our overall understanding of the interactions of neutrons with matter, accurately determining the effects of fast neutrons scattering from 12C is important. Previously measured 12C inelastic neutron scattering differential cross sections found in the National Nuclear Data Center (NNDC) show significant discrepancies (>30%). Seeking to resolve these discrepancies, neutron inelastic and elastic scattering differential cross sections for 12C were measured at the University of Kentucky Acceleratory Laboratory for incident neutron energies of 5.58, 5.83, and 6.04 MeV. Quasi mono-energetic neutrons were scattered off an enriched 12C target (>99.99%) and detected by a C6D6 liquid scintillation detector. Time-of-flight (TOF) techniques were used to determine scattered neutron energies and allowed for elastic/inelastic scattering distinction. Relative detector efficiencies were determined through direct measurements of neutrons produced by the 2H(d,n) and 3H(p,n) source reactions, and absolute normalization factors were found by comparing 1H scattering measurements to accepted NNDC values. This experimental procedure has been successfully used for prior neutron scattering measurements and seems well-suited to our current objective. Significant challenges were encountered, however, with measuring the neutron detector efficiency over the broad incident neutron energy range required for these measurements. Funding for this research was provided by the National Nuclear Security Administration (NNSA).

  3. Photodetachment cross-section evaluation using asymptotic considerations

    Science.gov (United States)

    Babilotte, Philippe; Vandevraye, Mickael

    2017-06-01

    Mathematical calculations are given concerning the evaluation of the negative ions photodetachment cross-section σ , into a so-called saturation regime. The interaction between a negative ion particle beam and a laser beam is examined under theoretical aspects. A quantitative criterion S is proposed to define the saturation threshold between the linear and the saturated domains, which are both present in this saturation regime. The asymptotic behaviours extracted at the low and high energy limits are used to determine this threshold quantitative criterion S and to evaluate also the photodetachment cross-section σ . The case of a symmetric gaussian photodetachment laser beam shape is examined according to the proposed formalism, which can be used either for the photo-detachment or photo-ionization processes, and could be potentially used into technological solutions for negative ion neutralisation processes (such as neutral beam injector) in the future fusion energy devices. Estimations onto the errors related to the use of this methodology are given.

  4. Preparation of TEM specimen by cross-section technique

    International Nuclear Information System (INIS)

    Hamada, Shozo

    1986-01-01

    Transmission electron microscopy (TEM) is applied to the direct observation of the depth dependent damage structure in ion-irradiated stainless steel by using the cross-section technique; obtaining the TEM specimen from a slice of the irradiated stainless steel with thick Ni plating. Here has been developed the specimen preparation method of cross-section technique without heat treatment, which was necessary in the conventional method to strengthen the bonding between Ni and stainless steel. Nickel plating with good bonding to stainless steel is enabled by the following manner. First, the irradiated stainless steel is immersed in the Wood's nickel solution at room temperature for 60s to activate the surface, followed by the stricking for 300s at a current density of 300 A/m 2 in the solution to make fine and homogeneous nucleation of Ni on the stainless steel. Then, the sample is plated with Ni in the Watt's nickel plating solution at 333 K with current density of 900 ∼ 1,000 A/m 2 . The TEM disc is obtained by mechanical slicing from the specimen with Ni plating of more than 3 mm thickness. Electropolishing is accomplished by using both Ballmann method and jet electropolishing to perforate the disc accurately at the aimed point for the observation of the damage structure. (author)

  5. Spinal trauma: first aid from cross-sectional imaging

    International Nuclear Information System (INIS)

    Schueller, G.; Schueller-Weidekamm, C.

    2014-01-01

    The diagnosis of the traumatized spine is one of the key issues for trauma radiologists. The cross-sectional imaging procedures, computed tomography (CT) and magnetic resonance imaging (MRI) are the essential methods in spinal trauma radiology. These modalities are of great help in accurately assessing injury patterns and extent and in providing indications of patient outcome. In contrast to cross-sectional imaging, radiography has a role in the evaluation of minor spinal trauma only. It is generally accepted that trauma radiologists do not use typical classifications to evaluate the spine partly because such an ideal classification system does not yet exist. Not least because of this classification difficulty, eponyms and synonyms are widely used to describe traumatology of the spine as a high level of specific information is included in these various terms. The members of the trauma team should be aware of the strengths and limitations of the methods used in the assessment of the spine. This article provides a brief outline of fundamental knowledge about the diagnosis of spinal trauma. (orig.) [de

  6. A global analysis of inclusive diffractive cross sections at HERA

    International Nuclear Information System (INIS)

    Royon, C.; Schoeffel, L.; Sapeta, S.; Peschanski, R.; Sauvan, E.

    2006-10-01

    We describe the most recent data on the diffractive structure functions from the H1 and ZEUS Collaborations at HERA using four models. First, a Pomeron Structure Function (PSF) model, in which the Pomeron is considered as an object with parton distribution functions. Then, the Bartels Ellis Kowalski Wuesthoff (BEKW) approach is discussed, assuming the simplest perturbative description of the Pomeron using a two-gluon ladder. A third approach, the Bialas Peschanski (BP) model, based on the dipole formalism is then described. Finally, we discuss the Golec-Biernat-Wuesthoff (GBW) saturation model which takes into account saturation effects. The best description of all available measurements can be achieved with either the PSF based model or the BEKW approach. In particular, the BEKW prediction allows to include the highest β measurements, which are dominated by higher twists effects and provide an efficient and compact parametrisation of the diffractive cross section. The two other models also give a good description of cross section measurements at small x with a small number of parameters. The comparison of all predictions allows us to identify interesting differences in the behaviour of the effective pomeron intercept and in the shape of the longitudinal component of the diffractive structure functions. In this last part, we present some features that can be discriminated by new experimental measurements, completing the HERA program. (authors)

  7. Radar Cross Section measurements on the stealth metamaterial objects

    DEFF Research Database (Denmark)

    Iwaszczuk, Krzysztof; Fan, Kim; Strikwerda, Andrew C.

    Absorbing metamaterials (MM) offer the exciting possibility of near-unity absorption at specific resonance frequencies where the characteristic impedance Z(ω) is designed to match the free-space impedance and the imaginary part of the refractive index κ(ω) is as high as possible. Such materials...... have been realized in the form of thin, flexible metallized films of polyimide [1]. Here we apply a near-unity absorbing MM as a way to reduce the radar cross section of an object, and consider the real-life situation where the probe beam is significantly larger than the MM film and the object under...... investigation. We use a terahertz radar cross section (RCS) setup [2] for the characterization of the RCS of a real object covered with an absorbing MM film designed for high absorption in the THz frequency range, specifically at 0.8 THz. The results are in a form of 2D maps (sinograms), from which the RCS...

  8. Rosenbluth Separation of the π0 Electroproduction Cross Section

    Science.gov (United States)

    Defurne, M.; Mazouz, M.; Ahmed, Z.; Albataineh, H.; Allada, K.; Aniol, K. A.; Bellini, V.; Benali, M.; Boeglin, W.; Bertin, P.; Brossard, M.; Camsonne, A.; Canan, M.; Chandavar, S.; Chen, C.; Chen, J.-P.; de Jager, C. W.; de Leo, R.; Desnault, C.; Deur, A.; El Fassi, L.; Ent, R.; Flay, D.; Friend, M.; Fuchey, E.; Frullani, S.; Garibaldi, F.; Gaskell, D.; Giusa, A.; Glamazdin, O.; Golge, S.; Gomez, J.; Hansen, O.; Higinbotham, D.; Holmstrom, T.; Horn, T.; Huang, J.; Huang, M.; Huber, G. M.; Hyde, C. E.; Iqbal, S.; Itard, F.; Kang, Ho.; Kang, Hy.; Kelleher, A.; Keppel, C.; Koirala, S.; Korover, I.; LeRose, J. J.; Lindgren, R.; Long, E.; Magne, M.; Mammei, J.; Margaziotis, D. J.; Markowitz, P.; Martí Jiménez-Argüello, A.; Meddi, F.; Meekins, D.; Michaels, R.; Mihovilovic, M.; Muangma, N.; Muñoz Camacho, C.; Nadel-Turonski, P.; Nuruzzaman, N.; Paremuzyan, R.; Puckett, A.; Punjabi, V.; Qiang, Y.; Rakhman, A.; Rashad, M. N. H.; Riordan, S.; Roche, J.; Russo, G.; Sabatié, F.; Saenboonruang, K.; Saha, A.; Sawatzky, B.; Selvy, L.; Shahinyan, A.; Sirca, S.; Solvignon, P.; Sperduto, M. L.; Subedi, R.; Sulkosky, V.; Sutera, C.; Tobias, W. A.; Urciuoli, G. M.; Wang, D.; Wojtsekhowski, B.; Yao, H.; Ye, Z.; Zana, L.; Zhan, X.; Zhang, J.; Zhao, B.; Zhao, Z.; Zheng, X.; Zhu, P.; Jefferson Lab Hall A Collaboration

    2016-12-01

    We present deeply virtual π0 electroproduction cross-section measurements at xB=0.36 and three different Q2 values ranging from 1.5 to 2 GeV 2 , obtained from Jefferson Lab Hall A experiment E07-007. The Rosenbluth technique is used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component and, thus, is far from the asymptotic limit predicted by perturbative quantum chromodynamics. Nonetheless, an indication of a nonzero longitudinal contribution is provided by the measured interference term σL T. Results are compared with several models based on the leading-twist approach of generalized parton distributions (GPDs). In particular, a fair agreement is obtained with models in which the scattering amplitude includes convolution terms of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. This experiment, together with previous extensive unseparated measurements, provides strong support to the exciting idea that transversity GPDs can be accessed via neutral pion electroproduction in the high-Q2 regime.

  9. Near threshold electron impact ionization cross section for tellurium atoms

    International Nuclear Information System (INIS)

    Chipev, F.F.; Chernyshova, I.V.; Kontros, J.E.; Shpenik, O.B.

    2004-01-01

    Full text: Up today electron-impact ionization is one of the most intensively investigated processes in atomic and molecular physics [1]. These experiments however, are associated with difficulties: high temperatures and densities are required to produce atomic beams and monochromatic intensive electron beams. A crossed electron and atomic beams scattering geometry was employed to measure the ionization efficiency curve for tellurium atoms. Our electron spectrometer comprises two serially mounted hypocycloidal electron energy analyzers [2], the first being the monochromator and the second - the scattered electron analyzer. The whole spectrometer is immersed into the homogenous magnetic field. Great care was taken in selecting the value of the extracting potential at the electrode, mounted normally to the atomic beam direction. By careful choosing this potential as low as possible (∼1.4 V), its influence on the motion of the monochromatized electrons in the collision region was minimized and the full collection of the formed ions was reached. The atom beam was produced using a compact effusion source made of the stainless steel with a microchannel exit to minimise the angular divergency of the beam. The temperature of the microchannel plate was taken about 50 K higher than that of the metal vapour in the heated reservoir. This atomic beam source enabled to produce an atomic beam with the concentration of two orders of magnitude higher than that in the case of a standard effusion source. A typical value of the electron energy spread was 0.15 eV (FWHM) in the 0.1-15 eV energy range. The primary electron beam current was equal to 10 -7 A. Such values of electron energy spread and beam current for the primary electron beam passing through the collision chamber were chosen to provide identical conditions for carrying out all the measurements. The energy scale was calibrated with the accuracy of ± 0.05 eV. The measured ionization cross-section normalized to the results

  10. Curves and tables of neutron cross sections of fission product nuclei in JENDL-3

    International Nuclear Information System (INIS)

    Nakagawa, Tsuneo

    1992-06-01

    Neutron cross sections of 172 nuclei in the fission product region stored in JENDL-3 are shown in graphs and tables. The evaluation work of these nuclei was made by the Fission Product Nuclear Data Working Group of the Japanese Nuclear Data Committee, in the neutron energy region from 10 -5 eV to 20 MeV. Almost all the cross section data are reproduced in graphs in this report. The cross section averaged over 38 energy intervals are listed in a table. Shown in other tables are thermal cross sections, resonance integrals, Maxwellian neutron flux average cross sections, fission spectrum average cross sections, 14-MeV cross sections, one group average cross sections in neutron flux of typical types of fission reactors and average cross sections in the 30-keV Maxwellian spectrum. (author)

  11. Curves and tables of neutron cross sections of fission product nuclei in JENDL-3

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Tsuneo [ed.

    1992-06-15

    Neutron cross sections of 172 nuclei in the fission product region stored in JENDL-3 are shown in graphs and tables. The evaluation work of these nuclei was made by the Fission Product Nuclear Data Working Group of the Japanese Nuclear Data Committee, in the neutron energy region from 10{sup {minus}5} eV to 20 MeV. Almost of the cross section data reproduced in graphs in this report. The cross section averaged over 38 energy intervals are listed in a table. Shown in order tables are thermal cross sections, resonance integrals, Maxwellian neutron flux average cross sections, fission spectrum average cross sections, 14-MeV cross sections, one group average cross sections in neutron flux of typical types of fission reactors and average cross sections in the 30-keV Maxwellian spectrum.

  12. Reducing cross-sectional data using a genetic algorithm method and effects on cross-section geometry and steady-flow profiles

    Science.gov (United States)

    Berenbrock, Charles E.

    2015-01-01

    Reduction of cross-sectional data using a genetic algorithm method, and the effects of data reduction on channel geometry and steady-flow profiles, were analyzed. Two reduction methods─standard and genetic algorithms─were used to reduce cross-sectional data from the Kootenai River in northern Idaho. Cross sections that are representative of meander, straight, braided, and canyon reaches were used to evalutate the reduction methods. Visual and hydraulic analyses were used to assess the methods. The genetic algorithm-reduced cross sections approximated the shape of the original cross sections better than the standard-reduced cross sections. A greater number of cross-sectional data points were needed for reduced cross sections in the straight reach, and even more in the braided reach, because a greater amount of data points are needed to adequately define cross sections that have greater topographic varability. For the genetic algorithm-reduction method, about 40 data points were needed to adequately define the shape of a reduced cross section in the braided reach compared to 10 to 20 data points in the meander and canyon reaches. The standard-reduction method needed about 70 data points for the braided reach and more than 30 points for the meander and canyon reaches. The genetic algorithm can effectively reduce data while staying within the threshold set by the maximum number of points to be included in the reduced dataset.

  13. $^{62}$Ni($n,\\gamma$) and $^{63}$Ni($n,\\gamma$) cross sections measured at n_TOF/CERN

    CERN Document Server

    Lederer, C; Berthoumieux, E; Colonna, N; Dressler, R; Guerrero, C; Gunsing, F; Kappeler, F; Kivel, N; Pignatari, M; Reifarth, R; Schumann, D; Wallner, A; Altstadt, S; Andriamonje, S; Andrzejewski, J; Audouin, L; Barbagallo, M; Becares, V; Becvar, F; Belloni, F; Berthier, B; Billowes, J; Boccone, V; Bosnar, D; Brugger, M; Calviani, M; Calvino, F; Cano-Ott, D; Carrapico, C; Cerutti, F; Chiaveri, E; Chin, M; Cortes, G; Cortes-Giraldo, M A; Dillmann, I; Domingo-Pardo, C; Duran, I; Dzysiuk, N; Eleftheriadis, C; Fernandez-Ordonez, M; Ferrari, A; Fraval, K; Ganesan, S; A.R.Garc i; Giubrone, G; Gomez-Hornillos, M B; Goncalves, I F; Gonzalez-Romero, E; Gramegna, F; Griesmayer, E; Gurusamy, P; Harrisopulos, S; Heil, M; Ioannides, K; Jenkins, D G; Jericha, E; Kadi, Y; Karadimos, D; Korschinek, G; Krticka, M; Kroll, J; Langer, C; Lebbos, E; Leeb, H; Leong, L S; Losito, R; Lozano, M; Manousos, A; Marganiec, J; Marrone, S; Martinez, T; Mastinu, P F; Mastromarco, M; Meaze, M; Mendoza, E; Mengoni, A; Milazzo, P M; Mingrone, F; Mirea, M; Mondalaers, W; Paradela, C; Pavlik, A; Perkowski, J; Plag, R; Plompen, A; Praena, J; Quesada, J M; Rauscher, T; Riego, A; Roman, F; Rubbia, C; Sarmento, R; Schillebeeckx, P; Schmidt, S; Tagliente, G; Tain, J L; D.Tarr i; Tassan-Got, L; Tsinganis, A; Tlustos, L; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Vermeulen, M J; Versaci, R; Vlachoudis, V; Vlastou, R; Ware, T; Weigand, M; Weiss, C; Wright, T J; Zugec, P

    2014-01-01

    The cross section of the $^{62}$Ni($n,\\gamma$) reaction was measured with the time-of-flight technique at the neutron time-of-flight facility n_TOF at CERN. Capture kernels of 42 resonances were analyzed up to 200~keV neutron energy and Maxwellian averaged cross sections (MACS) from $kT=5-100$ keV were calculated. With a total uncertainty of 4.5%, the stellar cross section is in excellent agreement with the the KADoNiS compilation at $kT=30$ keV, while being systematically lower up to a factor of 1.6 at higher stellar temperatures. The cross section of the $^{63}$Ni($n,\\gamma$) reaction was measured for the first time at n_TOF. We determined unresolved cross sections from 10 to 270 keV with a systematic uncertainty of 17%. These results provide fundamental constraints on $s$-process production of heavier species, especially the production of Cu in massive stars, which serve as the dominant source of Cu in the solar system.

  14. Activation measurements of neutron-capture cross sections in the MeV region

    International Nuclear Information System (INIS)

    Andersson, P.

    1985-04-01

    Activation measurements in the MeV region are frequently disturbed by accompanying low-energy background neutrons. These neutrons are produced by nonelastic neutron reactions (e.g. (n.n'), (n,np) and (n,2n) reactions) in the irradiated sample and surrounding materials as well as by charged-particle reactions in the target materials. Capture measurements are particularly sensitive, and the contribution to the activation yield may be significant already at 1-2 MeV. Experimental techniques for cross-section measurements were developed in which the background influence was minimized by the appropriate choice of target materials and experimental arrangements. The remaining contributions were determined by systematically varying the experimental conditions. The methods were applied to capture cross-section measurements for 115 In and 197 Au in the neutron energy region 2.0-7.7 MeV, and for 23 Na, 55 Mn, 89 Y, 127 I, 138 Ba, 186 W and 197 Au at 14.7 MeV. Cross sections for the reactions 27 Al(n,np) 27 Mg, 27 Al(n,α) 24 Na, 115 In(n,n') 115 sup(m)In and 197 Au(n,2n) 198 Au were also measured at 14.9 MeV. Some of the results are compared with statistical model calculations. (Author)

  15. Measurement of Compton scattering cross section during PrimEx-II Experiment at Jefferson Lab

    Science.gov (United States)

    Ye, Li; PrimEx Collaboration

    2017-09-01

    The electron Compton scattering is the most known fundamental QED process, however, a precision measurement of its cross section for the beam energy above 1 GeV has been lacking up to now. An updated high precision measurement of the neutral pion lifetime via the Primakoff effect (PrimEx-II) experiment was performed in Hall B of Jefferson Lab in 2010. The experiment used small angle coherent photoproduction of π0's in the Coulomb field of a nucleus, i.e. the Primakoff effect, to determine the lifetime with a precision of less than 1.5 % . It therefore requires thorough understanding of the underlying systematic uncertainties. To facilitate that data for well known electromagnetic processes were taken concurrently with the photoproduction data. This analysis pertains to measuring the Compton scattering cross section, which occurs at similar kinematics as the primary process. The combination of the well established theory of this process with large collected statistics allowed to extract this cross section with high precision in an energy region of 4-5 GeV for 12C and 28Si targets. The results of this analysis will be presented. This work is supported in part by the U.S. Department of Energy under Contacts No. DE-FG02-03ER41528, NSF MRI PHY-0079840, Thomas Jefferson National Laboratory, Mississippi State University and PrimEx collaboration.

  16. Measurements of fusion cross sections of the 16O+46,50Ti systems

    International Nuclear Information System (INIS)

    Liguori Neto, R.

    1986-01-01

    Excitation functions for complete fusion of the systems 16 O + 46,50 Ti, with energies near and below the Coulomb barrier, were measured. With the use of the in-beam and out of beam γ spectroscopy, the formation of the compound nucleus was experimentally detected. The fusion cross section was then attained by the sum of all observed compound nucleus decay channels. The limitation and advantages of measurements methods are discussed. Theoretical analysis of the experimental results using the semi-classical barrier penetration model allowed us to obtain the fusion barrier height and radius for the studied systems. These values are in good agreement with others reported for this mass range. Using the unidimensional barrier penetration model with different nuclear potentials, describing the heavy ion interactions gave theoretical fusion cross section values systematically smaller than our measured values in the energy region below the Coulomb barrier. The introduction of the nuclear surface zero point vibrations enhances the theoretical fusion cross sections in the sub-Coulomb region, but simultaneously introduces an isotopic difference in the fusion excitation functions that is not observed experimentally. The statistical model predictions for the compound nucleus decay (calculated by the CASCADE program) show reasonable agreement for the more intense decay channels [pt

  17. 16O(n,α) cross section investigation using LENZ instrument at LANSCE

    Science.gov (United States)

    Lee, H. Y.; Mosby, S.; Haight, R. C.; White, M. C.

    2016-06-01

    Importance of studying the 16O(n,α) reaction is motivated by multiple nuclear applications. The Los Alamos Neutron Science Center (LANSCE) produces a white neutron spectrum ranging from thermal to several hundreds of MeV energies. We have recently developed the LENZ (Low Energy NZ-neutron induced charged particle detection) capability to measure high-precision (n,α) cross sections. In order to provide more reliable data, we have enhanced solid angle coverage, and improved signal-to-noise ratios and time-of-flight resolution by implementing digitizer waveform analysis. The LENZ was commissioned by studying the 59Co(n,α) reaction with neutron beams in early 2015. For the 16O(n,α) reaction, we investigate solid oxygen targets and make a relative measurement to a better known cross section, such as the 6Li(n,α) reaction in order to further reduce systematic uncertainty. We will discuss the progress of the 16O(n,α) study at LANSCE and the outlook for improving Hauser-Feshbah prediction on (n,p) reaction cross sections.

  18. 16O(n,α cross section investigation using LENZ instrument at LANSCE

    Directory of Open Access Journals (Sweden)

    Lee H.Y.

    2016-01-01

    Full Text Available Importance of studying the 16O(n,α reaction is motivated by multiple nuclear applications. The Los Alamos Neutron Science Center (LANSCE produces a white neutron spectrum ranging from thermal to several hundreds of MeV energies. We have recently developed the LENZ (Low Energy NZ-neutron induced charged particle detection capability to measure high-precision (n,α cross sections. In order to provide more reliable data, we have enhanced solid angle coverage, and improved signal-to-noise ratios and time-of-flight resolution by implementing digitizer waveform analysis. The LENZ was commissioned by studying the 59Co(n,α reaction with neutron beams in early 2015. For the 16O(n,α reaction, we investigate solid oxygen targets and make a relative measurement to a better known cross section, such as the 6Li(n,α reaction in order to further reduce systematic uncertainty. We will discuss the progress of the 16O(n,α study at LANSCE and the outlook for improving Hauser-Feshbah prediction on (n,p reaction cross sections.

  19. Measurement of the total photoabsorption cross sections of hydrogen and helium-3 in the resonance zone

    International Nuclear Information System (INIS)

    Mac Cormick, Marion

    1993-01-01

    This thesis describes an experimental study of the total photoabsorption cross sections of hydrogen and helium-3. The results shown for hydrogen are not only in agreement with the previously published data but are superior in precision with smaller statistical and systematic fluctuations. The results for helium-3 present the first measurement of the total cross section. These studies are part of a general systematic study devoted to the exploration of the resonance damping which is observed in the passage of photoabsorption by light nuclei to heavy nuclei. Extremely high quality data were obtained thanks to the excellent experimental conditions. The measurements were obtained with photons of 100-800 MeV provided by Bremsstrahlung of the electron beam of the MAMI accelerator (Mainz, Germany). Reaction products were detected in the large acceptance detector DAPHNE. Details of the experimental set-up, the analysis method and a discussion of the results form the main bulk of this thesis. However, some consideration is also given to recent developments in the theoretical models used to explain the resonance damping. (author)

  20. Neutron-induced cross-sections via the surrogate method

    International Nuclear Information System (INIS)

    Boutoux, G.

    2011-11-01

    The surrogate reaction method is an indirect way of determining neutron-induced cross sections through transfer or inelastic scattering reactions. This method presents the advantage that in some cases the target material is stable or less radioactive than the material required for a neutron-induced measurement. The method is based on the hypothesis that the excited nucleus is a compound nucleus whose decay depends essentially on its excitation energy and on the spin and parity state of the populated compound state. Nevertheless, the spin and parity population differences between the compound-nuclei produced in the neutron and transfer-induced reactions may be different. This work reviews the surrogate method and its validity. Neutron-induced fission cross sections obtained with the surrogate method are in general good agreement. However, it is not yet clear to what extent the surrogate method can be applied to infer radiative capture cross sections. We performed an experiment to determine the gamma decay probabilities for 176 Lu and 173 Yb by using the surrogate reactions 174 Yb( 3 He,pγ) 176 Lu * and 174 Yb( 3 He,αγ) 173 Yb * , respectively, and compare them with the well-known corresponding probabilities obtained in the 175 Lu(n,γ) and 172 Yb(n,γ) reactions. This experiment provides answers to understand why, in the case of gamma-decay, the surrogate method gives significant deviations compared to the corresponding neutron-induced reaction. In this work, we have also assessed whether the surrogate method can be applied to extract capture probabilities in the actinide region. Previous experiments on fission have also been reinterpreted. Thus, this work provides new insights into the surrogate method. This work is organised in the following way: in chapter 1, the theoretical aspects related to the surrogate method will be introduced. The validity of the surrogate method will be investigated by means of statistical model calculations. In chapter 2, a review on