Science.gov

Sample records for cross-sectional descriptive correlational

  1. Correlation cross sections along the international border

    SciTech Connect

    Martiniuk, C.D. ); Le Fever, J.A.; Anderson, S.B. )

    1991-06-01

    The Manitoba-North Dakota (Canada-US) stratigraphic correlation project is a joint study between the Petroleum Branch of Manitoba Energy and Mines and the North Dakota Geological Survey. It is an attempt to correlate the differing stratigraphic terminologies established in the two jurisdictions by providing a reference cross section across the international boundary. The study involves the subsurface correlation of logs of the Paleozoic and Mesozoic sequences in the Manitoba and North Dakota portions of the Williston basin. The Paleozoic and Mesozoic sequences are subdivided for presentation into the following stratigraphic intervals: (a) Cambrian-Ordovician-Silurian, (b) Devonian, (c) Mississippian, (d) Jurassic, and (e) Cretaceous. Wireline logs show the actual stratigraphic correlations. A nomenclature chart is also presented from each sequence. In addition, the sections include a generalized description of lithologies, thicknesses, environments of deposition, and petroleum potential for each geographic area.

  2. The association between stressful life events and depressive symptoms among Cypriot university students: a cross-sectional descriptive correlational study

    PubMed Central

    2013-01-01

    Background Previous findings suggest that stressful life events have a causal relationship with depressive symptoms. However, to date little is known concerning the contribution of the number and severity of recent stressful life events on the prevalence of depressive symptoms among university students. The aim of this study was to investigate the prevalence of depressive symptoms and its association with the number and the severity of self-reported stressful life events among university students in Cyprus. Methods A descriptive correlational design with cross sectional comparison was used. The CES-D scale was applied for the assessment of depressive symptoms and the LESS instrument for stressful life events. Both scales were completed anonymously and voluntarily by 1.500 students (response rate 85%). Results The prevalence of mild to moderate depressive symptoms [CES-D score between 16 and 21] and of clinically significant depressive symptoms [CES-D score???22] were 18.8% and 25.3% respectively. There were statistically significant differences in clinically significant depressive symptoms by gender, with higher rates among women (x2?=?8.53, df?=?1, p?=?0.003). Higher scores on the LESS scale were associated with more frequent reports of clinical depressive symptoms (x2?=?70.63, df?=?4, p??351, OR?=?3.03 95% CI: 1.66, 5.39) were more likely to manifest clinical depressive symptoms. Conclusions The high frequency of occurrence of depressive symptoms among Cypriot university students, as well as the strong association with stressful life events, highlights the need for psychological empowerment strategies towards students by institutional counseling services. PMID:24304515

  3. Impact of Reaction Cross Section on the Unified Description of Fusion Excitation Function

    NASA Astrophysics Data System (ADS)

    Basrak, Z.; Eudes, P.; de la Mota, V.; Sébille, F.; Royer, G.

    A systematics of over 300 complete and incomplete fusion cross section data points covering energies beyond the barrier for fusion is presented. Owing to a usual reduction of the fusion cross sections by the total reaction cross sections and an original scaling of energy, a fusion excitation function common to all the data points is established. A universal description of the fusion exci- tation function relying on basic nuclear concepts is proposed and its dependence on the reaction cross section used for the cross section normalization is discussed. The pioneering empirical model proposed by Bass in 1974 to describe the complete fusion cross sections is rather successful for the incomplete fusion too and provides cross section predictions in satisfactory agreement with the observed universality of the fusion excitation function. The sophisticated microscopic transport DYWAN model not only reproduces the data but also predicts that fusion reaction mechanism disappears due to weakened nuclear stopping power around the Fermi energy.

  4. Semiclassical description of the small angle differential cross section for elastic atom—atom scattering

    NASA Astrophysics Data System (ADS)

    Beijerinck, H. C. W.; van der Kam, P. M. A.; Thijssen, W. J. G.; Verster, N. F.

    1980-01-01

    The scattering amplitude is investigated for small angles ?* ? 8.5, with ?* = ?/? o a reduced scattering angle. The scaling angle is ? o = (4?/ k2Q3) 1/2, with k the wavenumber and Q3 the total cross section due to the attractive branch of the intermolecular potential. Both pure inverse power potentials and realistic intermolecular potentials are investigated. The method used is a least-square curve fit of the real and imaginary parts of quantum-mechanically calculated scattering amplitudes f(?) with suitable model functions. The shape of these model functions is partially based on the classical and semiclassical results for small angle scattering. For the shape of the attractive contribution to the differential cross section ? 3(?) in the case of an inverse power potential we give a new model function that describe the quantum oscillations (diffraction) modulating the classical result ? e1(?) HE for the differential cross section in the high energy approximation, i.e. the approximation of a straight line trajectory. The first order correction on this straight line approximation is also derived and incorporated in our model function. For s = 6 and 2.5 ? ?* ? 8.5 we find a description of ? 3(?)/? e1(?) HE with a rms deviation of 2.3 × 10 -3. For the shape of the differential cross section at small angles we give a second, new semi-empirical model functions, ? 3(?)/? 3(0) = [1 -1 c1 sin ( c2?* 2) + c3?* 2] -(3 + 1)/3, with s the power of the potential. The asymptotic behaviour of this function for ?* ? 1 and ?* ? is in good agreement with the corresponding semiclassical and classical results. For s = 6 the parameters are c1 = 3.75, c2 = 0.556, and c3 = 2.94, resulting in a description of ? 3(?)/? 3(0) with a rms deviation of 0.9 × 10 -3 for ?* ? 4.0. A simple and accurate model function for the phase angle ? a(?) = arg( f(?)) enables us to include the glory behaviour in the case of a realistic intermolecular potential. For the analysis of the differential cross section of a realistic potential a suitable model function for the glory contribution is added, resulting in a description of ?(?)/?(0) with a rms deviation of 3 × 10 -3 for ?* ? 4.0. A universal set of parameters is presented that can be used for predicting the differential cross section for a realistic intermolecular potential. It is also shown that the velocity dependency of the attractive and the glory contribution to the imaginary part of the scattering amplitude for ?* = 0, i.e. the total cross section, can be effectively used for predicting the small angle behaviour of the differential cross section.

  5. Neutron field reconstruction with consideration of the spatial correlation of the cross-section value error

    SciTech Connect

    Semyonov, A. A.; Druzhaev, A. A. Schukin, N. V.

    2014-12-15

    A method for reconstructing the neutron field in a reactor with consideration of the spatial correlation of the cross-section value error was analyzed. It was shown that this method is more accurate than the classical approach to reconstruction. An efficient way of using this technique was proposed. The efficiency for the RBMK critical test facility was estimated.

  6. Nucleus-nucleus cross-sections and long-range correlations with a local supercritical pomeron

    E-print Network

    M. A. Braun

    2007-11-21

    Nucleus-nucleus scattering is studied in the local Reggeon Field Theory in the quasi-classical approximation with non-eikonal boundary conditions corresponding to the Glauber picture at low energies. Comparison with the commonly used eikonal boundary conditions shows that the new conditions make both the action and nucleus-nucleus total cross-sections lower by $3\\div 5$ %. They also substantially change the behaviour of the solutions of the equations of motion at low energies. Using expressions for the double inclusive cross-sections derived earlier in the Reggeon Field Theory \\cite{CM} long-range rapidity correlations are calculated for the RHIC and LHC energies.

  7. Total 4He Photoabsorption Cross Section Revisited: Correlated HH versus Effective Interaction HH

    E-print Network

    Nir Barnea; Victor D. Efros; Winfried Leidemann; Giuseppina Orlandini

    2000-10-23

    Two conceptually different hyperspherical harmonics expansions are used for the calculation of the total 4He photoabsorption cross section. Besides the well known method of CHH the recently introduced effective interaction approach for the hyperspherical formalism is applied. Semi-realistic NN potentials are employed and final state interaction is fully taken into account via the Lorentz integral transform method. The results show that the effective interaction leads to a very good convergence, while the correlation method exhibits a less rapid convergence in the giant dipole resonance region. The rather strong discrepancy with the experimental photodisintegration cross sections is confirmed by the present calculations.

  8. Inclusive jet cross sections and dijet correlations in D photoproduction at HERA

    NASA Astrophysics Data System (ADS)

    Chekanov, S.; Derrick, M.; Magill, S.; Miglioranzi, S.; Musgrave, B.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Pavel, N.; Yagües Molina, A. G.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cara Romeo, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; De Pasquale, S.; Giusti, P.; Iacobucci, G.; Margotti, A.; Montanari, A.; Nania, R.; Palmonari, F.; Pesci, A.; Polini, A.; Rinaldi, L.; Sartorelli, G.; Zichichi, A.; Aghuzumtsyan, G.; Bartsch, D.; Brock, I.; Goers, S.; Hartmann, H.; Hilger, E.; Irrgang, P.; Jakob, H.-P.; Kind, O. M.; Meyer, U.; Paul, E.; Rautenberg, J.; Renner, R.; Wang, M.; Wlasenko, M.; Bailey, D. S.; Brook, N. H.; Cole, J. E.; Heath, G. P.; Namsoo, T.; Robins, S.; Capua, M.; Fazio, S.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Tassi, E.; Kim, J. Y.; Ma, K. J.; Helbich, M.; Ning, Y.; Ren, Z.; Schmidke, W. B.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Gil, M.; Olkiewicz, K.; Stopa, P.; Szuba, D.; Zawiejski, L.; Adamczyk, L.; Bo?d, T.; Grabowska-Bo?d, I.; Kisielewska, D.; ?ukasik, J.; Przybycie?, M.; Suszycki, L.; Szuba, J.; Kota?ski, A.; S?omi?ski, W.; Adler, V.; Behrens, U.; Bloch, I.; Borras, K.; Drews, G.; Fourletova, J.; Geiser, A.; Gladkov, D.; Göttlicher, P.; Gutsche, O.; Haas, T.; Hain, W.; Horn, C.; Kahle, B.; Kötz, U.; Kowalski, H.; Kramberger, G.; Lim, H.; Löhr, B.; Mankel, R.; Melzer-Pellmann, I.-A.; Nguyen, C. N.; Notz, D.; Nuncio-Quiroz, A. E.; Raval, A.; Santamarta, R.; Schneekloth, U.; Stadie, H.; Stösslein, U.; Wolf, G.; Youngman, C.; Zeuner, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Genta, C.; Pelfer, P. G.; Bamberger, A.; Benen, A.; Karstens, F.; Dobur, D.; Vlasov, N. N.; Bussey, P. J.; Doyle, A. T.; Dunne, W.; Ferrando, J.; McKenzie, J. H.; Saxon, D. H.; Skillicorn, I. O.; Gialas, I.; Carli, T.; Gosau, T.; Holm, U.; Krumnack, N.; Lohrmann, E.; Milite, M.; Salehi, H.; Schleper, P.; Schörner-Sadenius, T.; Stonjek, S.; Wichmann, K.; Wick, K.; Ziegler, A.; Ziegler, Ar.; Collins-Tooth, C.; Foudas, C.; Fry, C.; Gonçalo, R.; Long, K. R.; Tapper, A. D.; Kataoka, M.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Pokrovskiy, N. S.; Zhautykov, B. O.; Son, D.; de Favereau, J.; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; Jimenez, M.; Labarga, L.; del Peso, J.; Terrón, J.; Zambrana, M.; Corriveau, F.; Liu, C.; Plamondon, M.; Robichaud-Veronneau, A.; Walsh, R.; Zhou, C.; Tsurugai, T.; Antonov, A.; Dolgoshein, B. A.; Rubinsky, I.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Gladilin, L. K.; Katkov, I. I.; Khein, L. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Zotkin, D. S.; Zotkin, S. A.; Abt, I.; Büttner, C.; Caldwell, A.; Liu, X.; Sutiak, J.; Coppola, N.; Grigorescu, G.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Maddox, E.; Tiecke, H.; Vázquez, M.; Wiggers, L.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Lee, A.; Ling, T. Y.; Allfrey, P. D.; Bell, M. A.; Cooper-Sarkar, A. M.; Cottrell, A.; Devenish, R. C. E.; Foster, B.; Gwenlan, C.; Kohno, T.; Korcsak-Gorzo, K.; Patel, S.; Roberfroid, V.; Straub, P. B.; Walczak, R.; Bellan, P.; Bertolin, A.; Brugnera, R.; Carlin, R.; Ciesielski, R.; Dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Stanco, L.; Turcato, M.; Heaphy, E. A.; Metlica, F.; Oh, B. Y.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Hart, J. C.; Abramowicz, H.; Gabareen, A.; Kananov, S.; Kreisel, A.; Levy, A.; Kuze, M.; Kagawa, S.; Tawara, T.; Hamatsu, R.; Kaji, H.; Kitamura, S.; Matsuzawa, K.; Ota, O.; Ri, Y. D.; Costa, M.; Ferrero, M. I.; Monaco, V.; Sacchi, R.; Solano, A.; Arneodo, M.; Ruspa, M.; Fourletov, S.; Martin, J. F.; Butterworth, J. M.; Hall-Wilton, R.; Jones, T. W.; Loizides, J. H.; Sutton, M. R.; Targett-Adams, C.; Wing, M.; Ciborowski, J.; Grzelak, G.; Kulinski, P.; ?u?niak, P.; Malka, J.; Nowak, R. J.; Pawlak, J. M.; Sztuk, J.; Tymieniecka, T.; Ukleja, A.; Ukleja, J.; ?arnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Hochman, D.; Karshon, U.; Lightwood, M. S.; Brownson, E.; Danielson, T.; Everett, A.; Kçira, D.; Lammers, S.; Li, L.; Reeder, D. D.; Rosin, M.; Ryan, P.; Savin, A. A.; Smith, W. H.; Dhawan, S.; Bhadra, S.; Catterall, C. D.; Cui, Y.; Hartner, G.; Menary, S.; Noor, U.; Soares, M.; Standage, J.; Whyte, J.; ZEUS Collaboration

    2005-11-01

    Inclusive jet cross sections in photoproduction for events containing a D meson have been measured with the ZEUS detector at HERA using an integrated luminosity of 78.6 pb. The events were required to have a virtuality of the incoming photon, Q, of less than 1 GeV 2, and a photon-proton centre-of-mass energy in the range 130cross sections are also compared to Monte Carlo (MC) models which incorporate leading-order matrix elements followed by parton showers and hadronisation. The NLO QCD predictions are in general agreement with the data although differences have been isolated to regions where contributions from higher orders are expected to be significant. The MC models give a better description than the NLO predictions of the shape of the measured cross sections.

  9. Fate of Articles That Warranted Retraction Due to Ethical Concerns: A Descriptive Cross-Sectional Study

    PubMed Central

    Elia, Nadia; Wager, Elizabeth; Tramèr, Martin R.

    2014-01-01

    Objective To study journals' responses to a request from the State Medical Association of Rheinland-Pfalz, Germany, to retract 88 articles due to ethical concerns, and to check whether the resulting retractions followed published guidelines. Design Descriptive cross-sectional study. Population 88 articles (18 journals) by the anaesthesiologist Dr. Boldt, that warranted retraction. Method According to the recommendations of the Committee on Publication Ethics, we regarded a retraction as adequate when a retraction notice was published, linked to the retracted article, identified the title and authors of the retracted article in its heading, explained the reason and who took responsibility for the retraction, and when the retracted article was freely accessible and marked using a transparent watermark that preserved original content. Two authors extracted data independently (January 2013) and contacted editors-in-chief and publishers for clarification in cases of inadequate retraction. Results Five articles (6%) fulfilled all criteria for adequate retraction. Nine (10%) were not retracted (no retraction notice published, full text article not marked). 79 (90%) retraction notices were published, 76 (86%) were freely accessible, but only 15 (17%) were complete. 73 (83%) full text articles were marked as retracted, of which 14 (16%) had an opaque watermark hiding parts of the original content, and 11 (13%) had all original content deleted. 59 (67%) retracted articles were freely accessible. One editor-in-chief stated personal problems as a reason for incomplete retractions, eight blamed their publishers. Two publishers cited legal threats from Dr. Boldt's co-authors which prevented them from retracting articles. Conclusion Guidelines for retracting articles are incompletely followed. The role of publishers in the retraction process needs to be clarified and standards are needed on marking retracted articles. It remains unclear who should check that retractions are done properly. Legal safeguards are required to allow retraction of articles against the wishes of authors. PMID:24465744

  10. A Cross-Sectional Study Examining Youth Smoking Rates and Correlates in Tbilisi, Georgia

    PubMed Central

    Berg, Carla J.; Aslanikashvili, Ana; Djibuti, Mamuka

    2014-01-01

    Georgia has high smoking rates; however, little is known about the prevalence and correlates of youth smoking. We conducted a secondary data analysis of a 2010 cross-sectional survey of 1,879 secondary and postsecondary school students aged 15 to 24 years in Tbilisi, Georgia, examining substance use, perceived risk, and recreational activities in relation to lifetime and current (past 30 days) smoking. Lifetime and current smoking prevalence was 46.1% and 22.6%, respectively. In secondary schools, lifetime smoking correlates included being male, consuming alcohol, lifetime marijuana use, and lower perceived risk (P's ? .001). Correlates of current smoking among lifetime smokers included being male, consuming alcohol, lifetime marijuana use, lower perceived risk, less frequently exercise, and more often going out (P's < .05). In postsecondary schools, lifetime smoking correlates included being male, consuming alcohol, lifetime marijuana use, lower perceived risk, more often going out, and recreational internet use (P's < .0). Correlates of current smoking among lifetime smokers included being male (P's = .04), consuming alcohol, marijuana use, lower perceived risk, and more often going out (P's < .05). Tobacco control interventions might target these correlates to reduce smoking prevalence in Georgian youth. PMID:24738059

  11. Screening premorbid metabolic syndrome in community pharmacies: a cross-sectional descriptive study

    PubMed Central

    2014-01-01

    Background Premorbid metabolic syndrome (pre-MetS) is a cluster of cardiometabolic risk factors characterised by central obesity, elevated fasting glucose, atherogenic dyslipidaemia and hypertension without established cardiovascular disease or diabetes. Community pharmacies are in an excellent position to develop screening programmes because of their direct contact with the population. The main aim of the study was to determine the prevalence of pre-MetS in people who visited community pharmacies for measurement of any of its five risk factors to detect the presence of other risk factors. The secondary aims were to study the presence of other cardiovascular risk factors and determine patients’ cardiovascular risk. Methods Cross-sectional, descriptive, multicentre study. Patients meeting selection criteria aged between 18 and 65 years who visited participating community pharmacies to check any of five pre-MetS diagnostic factors were included.The study involved 23 community pharmacies in Catalonia (Spain). Detection criteria for pre-MetS were based on the WHO proposal following IDF and AHA/NHBI consensus. Cardiovascular risk (CVR) was calculated by Regicor and Score methods. Other variables studied were smoking habit, physical activity, body mass index (BMI), and pharmacological treatment of dyslipidemia and hypertension. The data were collected and analysed with the SPSS programme. Comparisons of variables were carried out using the Student’s T-test, Chi-Squared test or ANOVA test. Level of significance was 5% (0.05). Results The overall prevalence of pre-MetS was 21.9% [95% CI 18.7-25.2]. It was more prevalent in men, 25.5% [95% CI 22.1-28.9], than in women, 18.6% [95% CI 15.5-21.7], and distribution increased with age. The most common risk factors were high blood pressure and abdominal obesity. About 70% of people with pre-MetS were sedentary and over 85% had a BMI ?25 Kg/m2. Some 22.4% had two metabolic criteria and 27.2% of patients with pre-MetS had no previous diagnosis. Conclusions The prevalence of pre-MetS in our study (21.9%) was similar to that found in other studies carried out in Primary Care in Spain. The results of this study confirm emergent cardiometabolic risk factors such as hypertension, obesity and physical inactivity. Our study highlights the strategic role of the community pharmacy in the detection of pre-MetS in the apparently healthy population. PMID:24885099

  12. Description of alpha-nucleus interaction cross sections for cosmic ray shielding studies

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Townsend, Lawrence W.; Wilson, John W.

    1993-01-01

    Nuclear interactions of high-energy alpha particles with target nuclei important for cosmic ray studies are discussed. Models for elastic, quasi-elastic, and breakup reactions are presented and compared with experimental data. Energy-dependent interaction cross sections and secondary spectra are presented based on theoretical models and the limited experimental data base.

  13. Prevalence and Correlates of Binge Drinking among Young Adults Using Alcohol: A Cross-Sectional Survey

    PubMed Central

    Carrà, Giuseppe

    2014-01-01

    Background. Although binge drinking prevalence and correlates among young people have been extensively studied in the USA and Northern Europe, less is known for Southern Europe countries with relatively healthier drinking cultures. Objective. We aimed at analyzing prevalence and correlates of binge drinking in a representative sample of young adults in Italy. Methods. We conducted a cross-sectional survey among alcohol-consuming young adults. We carried out univariate and multivariate analyses to assess associations between recent binge drinking and candidate variables. Results. We selected 654 subjects, with 590 (mean age: 20.65 ± 1.90) meeting inclusion criteria. Prevalence for recent binge drinking was 38.0%, significantly higher for females than males. Multivariate analysis showed that high alcohol expectancies, large amount of money available during the weekend, interest for parties and discos, female gender, cannabis use, influence by peers, and electronic cigarettes smoking all were significantly associated with recent binge drinking, whereas living with parents appeared a significant protective factor. Conclusions. More than a third of young adults using alcohol are binge drinkers, and, in contrast with findings from Anglo-Saxon countries, females show higher risk as compared with males. These data suggest the increasing importance of primary and secondary prevention programmes for binge drinking. PMID:25101300

  14. Adult tobacco use practice and its correlates in eastern Ethiopia: A cross-sectional study

    PubMed Central

    2013-01-01

    Background There is paucity of data on the smoking habits of rural populations in developing countries. This study aimed to explore cigarette smoking practices of a rural community in Ethiopia. Methods A community based cross-sectional study was conducted among 548 individuals from a random sample of households in a rural town and its surrounding rural districts. Descriptive statistics and logistic regression were performed. Results Twenty-eight percent (95% CI: 24.3% - 31.6%) of the respondents were current smokers. A total of 105 (68%) smokers expressed an interest to quit while 37 (34%) had tried to quit previously but without success. There was high exposure to second-hand smoke: 285 (52%) homes allowed indoor smoking, and in 181 (33%) indoor smoking took place daily. Current smoking was strongly associated with male sex (OR?=?83.0; 95% CI: 11.5 – 599.0), and being a student was found to be protective of smoking (OR?=?0.04; 95% CI: 0.005 – 0.05). Conclusion Cigarette smoking is prevalent among the male rural town population in Ethiopia. In addition, a high level of exposure to indoor second-hand smoke exists. There is a need for investment in rural tobacco control, including educational campaigns and cost-effective smoking cessation services. PMID:24171800

  15. b-quark inclusive cross sections and b{bar b} correlations using dimuons from the D0 experiment

    SciTech Connect

    Vititoe, D.L.; D0 Collaboration

    1996-11-01

    Using dimuons collected with the D{null} detector during the 1993- 1995 Tevatron collider run, we have measured the {ital b}-quark cross section and {ital b{anti b}} correlations as given by the difference in azimuthal angle between the two muons. Both measurements agree with the NLO QCD predictions within experimental and theoretical errors.

  16. Sleep quality and its psychological correlates among university students in Ethiopia: a cross-sectional study

    PubMed Central

    2012-01-01

    Background Sleep is an important physiological process for humans. University students in most resource limited countries often report poor sleep quality due to changing social opportunities and increasing academic demands. However, sleep quality among university students has not been studied in Ethiopia. Thus, this study assessed sleep quality and its demographic and psychological correlates among university students. Methods A cross-sectional survey was conducted in two universities in Ethiopia. Multistage sampling procedures were used to enroll 2,817 students into the study. A self-administered structured questionnaire including the Pittsburgh Sleep Quality Index (PSQI), the Depression Anxiety Stress Scale-21, the Perceived Stress Scale (PSS) and selected modules of the World Health Organization STEPS instrument was used for the study. This research included 2,551 students. Frequency, median, mean with standard deviation and 95% confidence interval were used to characterize sleep quality and other variables. Analysis of variance and binary logistic regression procedures were also used. Result The prevalence of poor sleep quality (total PSQI score?>?5) was 55.8% (1,424). Female students (adjusted odds ratio (AOR) 1.23; 95% CI: 1.00, 1.57), second year (AOR 2.91; 95% CI: 2.1, 4.02) and third year students (AOR 2.25; 95% CI 1.62, 3.12) had statistically significant higher odds of poor sleep quality. Perceived stress level and symptoms of depression and anxiety were strongly associated with sleep quality. Conclusion A substantial proportion of university students are affected by poor sleep quality. If our results are confirmed in prospective studies, health promotion and educational programs for students should emphasize the importance of sleep and mental health. PMID:23270533

  17. The evolution of fetal presentation during pregnancy: a retrospective, descriptive cross-sectional study.

    PubMed

    Ferreira, Jose C P; Borowski, Dariusz; Czuba, Bartosz; Cnota, Wojciech; Wloch, Agata; Sodowski, Krzysztof; Wielgos, Miroslaw; Wegrzyn, Piotr

    2015-06-01

    We investigated changes in the frequencies of four primary types of singleton fetal lie/presentation for each gestational week from 18 to 39 weeks in a retrospective, cross-sectional study which analyzed ultrasound examination records of fetal positions, in the outpatient prenatal diagnosis clinics in two cities in Poland. We calculated the prevalence and 95% confidence intervals for each type of lie/presentation. We then identified the gestational age after which no statistically significant changes in terms of prevalence were observed, by comparing the results at each week with the prevalence of cephalic presentation at 39(+0) weeks, used as reference. A total of 18 019 ultrasound examinations were used. From 22 to 36 weeks of gestation, the prevalence of cephalic presentation increased from 47% (45-50%) to 94% (91-96%), before and after which times plateaus were noted. Spontaneous change from breech to cephalic is unlikely to occur after 36 weeks of gestation. PMID:25753199

  18. Correlation between nuclear charge radii of Ti and reaction cross sections for p -Ti

    NASA Astrophysics Data System (ADS)

    Hemalatha, M.; Maladkar, N.; Kailas, S.

    2015-08-01

    The nuclear root-mean-square charge radii and nuclear density distributions have been calculated in the framework of relativistic self-consistent mean-field models based on density-dependent meson-exchange relativistic energy density functional for even isotopes of Ti (A =44 -56 ). The calculations agree well with available laser spectroscopic measurements for 44,46,48,50Ti, and results for neutron-rich isotopes are reported. The semimicroscopic proton optical potentials for Ti-5644 have been derived by folding the target matter density with the extended Jeukenne-Lejeune-Mahaux energy- and density-dependent internucleon interaction and are used to calculate the differential elastic scattering and reaction cross sections at 65 MeV. The calculated differential cross sections reproduce the corresponding experimental values for stable even isotopes, and predictions are presented for 44,52,54,56Ti. The calculations reveal a prominent kink at the N =28 shell closure observed in the variation of reaction cross sections, consistent with mean-square charge radii systematics in the Ti isotopic chain.

  19. Efficacy of Percutaneous Epidural Neuroplasty Does Not Correlate with Dural Sac Cross-Sectional Area in Single Level Disc Disease

    PubMed Central

    Ji, Gyu Yeul; Oh, Chang Hyun; Moon, Bongju; Choi, Seung Hyun; Yoon, Young Sul; Kim, Keung Nyun

    2015-01-01

    Purpose Percutaneous epidural neuroplasty (PEN) is a minimally invasive treatment. The efficacy of PEN has been relatively well investigated; however, the relationship between the clinical effectiveness of PEN and the severity of spinal canal stenosis by disc material has not yet been established. The purpose of this study was to compare clinical outcomes of PEN according to the dural sac cross-sectional area in single level disc disease. Materials and Methods This study included 363 patients with back pain from single level disc disease with and without radiculopathy. Patients were categorized into groups according to spinal canal compromise by disc material: Category 1, less or more than 50%; and Category 2, three subgroups with lesser than a third, between a third and two thirds, and more than two thirds. Clinical outcomes were assessed according to the Visual Analog Scale (VAS) score for back pain and leg pain and Odom's criteria at 1, 3, 6, 12, and 24 months after treatment. Results The demographic data showed no difference between groups according to spinal canal compromise by disc material except age (older age correlated with more spinal canal compromise). The dural sac cross-sectional area did not correlate with the VAS scores for back and leg pain after PEN in single level disc disease in Groups 1 and 2. Odom's criteria after PEN were also not different according to dural sac cross-sectional area by disc material. Conclusion PEN is an effective procedure in treating single level lumbar disc herniation without affecting dural sac cross-sectional area. PMID:25837174

  20. Descriptive epidemiology of screen and non-screen sedentary time in adolescents: a cross sectional study

    PubMed Central

    2010-01-01

    Background Much attention has been paid to adolescents' screen time, however very few studies have examined non-screen sedentary time (NSST). This study aimed to (1) describe the magnitude and composition of screen sedentary time (SST) and NSST in Australian adolescents, (2) describe the socio-demographic correlates of SST and NSST, and (3) determine whether screen time is an adequate surrogate for total sedentary behaviour in this population. Methods 2200 9-16 year old Australians provided detailed use of time data for four days. Non-screen sedentary time (NSST) included time spent participating in activities expected to elicit <3 METs whilst seated or lying down (other than sleeping), excluding screen-based activities (television, playing videogames or using computers). Total sedentary time was the sum of screen time and NSST. Results Adolescents spent a mean (SD) of 345 (105) minutes/day in NSST, which constituted 60% of total sedentary time. School activities contributed 42% of NSST, socialising 19%, self-care (mainly eating) 16%, and passive transport 15%. Screen time and NSST showed opposite patterns in relation to key socio-demographic characteristics, including sex, age, weight status, household income, parental education and day type. Because screen time was negatively correlated with NSST (r = -0.58), and exhibited a moderate correlation (r = 0.53) with total sedentary time, screen time was only a moderately effective surrogate for total sedentary time. Conclusions To capture a complete picture of young people's sedentary time, studies should endeavour to measure both screen time and NSST. PMID:21194427

  1. Purely theoretical electron-impact ionization cross-sections of silicon hydrides and silicon fluorides obtained from explicitly correlated methods

    NASA Astrophysics Data System (ADS)

    Malcolm, N. O. J.; Yeager, Danny L.

    2000-07-01

    Electron impact total ionization cross-sections of small silicon hydrides, SiHn(n=1-4), and fluorides, SiFn(n=1-3), have been calculated by the application of a recently developed theoretical model. The binary-encounter-Bethe (BEB) model has a simple structure and requires information from calculations on the parent ground-state molecule only (binding energies, orbital kinetic energies, and occupation numbers). Previous applications of the BEB theory to the silicon hydrides and fluorides have employed a combination of experimental and Koopman's theorem binding energies. In the current work binding energies have been calculated using the explicitly correlated multiconfigurational spin tensor electron propagator (MCSTEP) method which gives highly accurate ionization potentials for closed- and open-shell systems. Calculations have been performed using cc-pVDZ and cc-pVTZ basis sets with multiconfigurational self-consistent field (MCSCF) reference wave functions. Comparisons are made between our MCSCF/MCSTEP and previous Hartree-Fock (HF)/Koopman's theorem results and available experimental data. The use of improved theoretical data does not have a significant effect on the resultant cross-sections; however, our new technique is a viable method for calculating electron impact ionization cross-sections for systems where Koopman's theorem is known to be unreliable or no experimental data is available.

  2. Adult criminal involvement: A cross-sectional inquiry into correlates and mechanisms over the life course

    PubMed Central

    DePadilla, Lara; Perkins, Molly M.; Elifson, Kirk W.; Sterk, Claire E.

    2013-01-01

    In this paper, we examine the relative contribution of four domains of predictors that have been linked to adult criminal involvement: (1) socio-demographic characteristics, (2) family-of-origin factors, (3) proximal processes developed during adolescence, and (4) current lifestyle and situational factors. Cross-sectional data were collected through face-to-face interviews with 242 community-recruited adults. Data analysis involved negative binomial regression. Being male, family size, juvenile delinquency, aggression, living with someone involved in illegal activity and recent violent victimization were independently associated with non-violent criminal involvement. Aggression, association with deviant peers, and recent violent victimization were independently associated with violent criminal involvement. Juvenile delinquency and aggression mediated the affect of multiple family-of-origin characteristics on non-violent criminal involvement and aggression mediated the effect of childhood physical abuse on violent criminal involvement. The results emphasize the importance of investigating both antecedents and proximal risk factors predictive of different types of criminal involvement, which, in turn, will assist in developing risk-focused prevention and intervention programs. PMID:24307752

  3. Prevalence and correlates of complementary and alternative medicine use among diabetic patients in Beirut, Lebanon: a cross-sectional study

    PubMed Central

    2014-01-01

    Background Patients with Type 2 Diabetes Mellitus (T2DM) are increasingly using complementary and alternative medicine (CAM) therapies due to difficulty in adhering to the therapeutic regimens and lifestyle changes necessary for disease management. Little is known about the prevalence and mode of CAM use among patients with T2DM in Lebanon. Objective To assess the prevalence and modes of CAM use among patients with T2DM residing in Beirut, Lebanon. Methods A cross-sectional survey of T2DM patients was conducted on patients recruited from two major referral centers in Beirut- a public hospital and a private academic medical center. In a face-to-face interview, participants completed a questionnaire comprised of three sections: socio-demographic, diabetes characteristics and types and modes of CAM use. Descriptive statistics, univariate and multivariate logistic regression analyses were utilized to assess the prevalence and correlates of CAM use, as well as whether the use was complementary or alternative to mainstream medicine. The main outcome in this study, CAM use, was defined as using CAM at least once since diagnosis with T2DM. Results A total of 333 T2DM patients completed the survey (response rate: 94.6%). Prevalence of CAM use since diagnosis with the disease was 38%. After adjustment, CAM use was significantly associated with a “married” status, a longer duration of T2DM, the presence of disease complications, and a positive family history of the disease. Folk foods and herbs were the most commonly used CAM followed by natural health products. One in five patients used CAM as alternative to conventional treatment. Only 7% of CAM users disclosed the CAM use to their treating physician. Health care practitioners were the least cited (7%) as influencing the choice of CAM among users. Conclusion The use of CAM therapies among T2DM patients in Lebanon is prevalent. Decision makers and care providers must fully understand the potential risks and benefits of CAM therapies to appropriately advise their patients. Attention must be dedicated to educating T2DM patients on the importance of disclosing CAM use to their physicians especially patients with a family history of diabetes, and those who have had the disease for a long time. PMID:24906634

  4. Prevalence and correlates of fecal incontinence among nursing home residents: a population-based cross-sectional study

    PubMed Central

    2013-01-01

    Background Fecal incontinence is highly prevalent among nursing home residents. Previous nursing home studies have identified co-morbidity associated with fecal incontinence, but as this population is increasingly old and frail, we wanted to see if the rate of fecal incontinence had increased and to investigate correlates of fecal incontinence further. Methods Cross-sectional study of the entire nursing home population in one Norwegian municipality. Registered nurses filled in a questionnaire for all residents in the municipality (980 residents aged ?65). Statistical methods used are descriptive statistics, binary logistic regression and multivariable logistic regression. Results The response rate of the study was 90.3%. The prevalence of fecal incontinence was 42.3%. In multivariable analysis of FI, residents with diarrhea (OR 7.33, CI 4.39-12.24), urinary incontinence (OR 2.77, CI 1.73-4.42) and dementia (OR 2.17, CI 1.28-3.68) had higher odds of having fecal incontinence compared to those without the condition. Residents residing in a nursing home between 4–5 years had higher odds of having fecal incontinence compared to residents who had stayed under a year (OR 2.65, CI 1.20-5.85). Residents with deficiency in feeding (2.17, CI 1.26-3.71), dressing (OR 4.03, CI 1.39-11.65), toilet use (OR 7.37, CI 2.65-20.44) and mobility (OR 2.54, CI 1.07-6.00) had higher odds of having fecal incontinence compared to residents without deficiencies in activities of daily living (ADL). Needing help for transfer between bed and chair was a protective factor for fecal incontinence compared to residents who transferred independently (OR 0.49, CI 0.26-0.91). Conclusions Fecal incontinence is a prevalent condition in the nursing home population and is associated with ADL decline, frailty, diarrhea and quality of care. This knowledge is important for staff in nursing home in order to provide the best treatment and care for residents with fecal incontinence. PMID:24119057

  5. Description of ( n, p) and ( n, 2n-activation cross sections for medium-mass nuclei within statistical multistep theory

    NASA Astrophysics Data System (ADS)

    Kalka, H.; Torjman, M.; Lien, H. N.; Lopez, R.; Seeliger, D.

    1990-06-01

    A unique description of ( n, p) and ( n, 2n) activation cross sections as well as emission spectra is proposed within a pure multistep approach. Calculations are presented for 8 nuclei ( A=47 ... 65) in the incident energy range from zero up to 20 MeV.

  6. Body dissatisfaction during pregnancy: a systematic review of cross-sectional and prospective correlates.

    PubMed

    Fuller-Tyszkiewicz, Matthew; Skouteris, Helen; Watson, Brittany E; Hill, Briony

    2013-11-01

    This article systematically reviews the literature pertaining to correlates of body dissatisfaction during pregnancy. A total of 8 electronic databases were searched and 251 papers identified, 56 of which met inclusion criteria. Full text scrutiny of these papers reduced the final list of reviewed papers to 22. Results of the review highlight that psychological factors were associated with body dissatisfaction during pregnancy, and noted the surfeit of studies examining the relationship was between body dissatisfaction and depression. It is concluded that the prevention of heightened body dissatisfaction during the reproductive phase will only be effective when models of risk factors have been examined systematically and rigorously. PMID:23188921

  7. Barrier contraception among adolescents and young adults in a tertiary institution in Southwestern Nigeria: a cross-sectional descriptive study.

    PubMed

    Olugbenga-Bello, Adenike I; Adekanle, Daniel A; Ojofeitimi, Ebenezer O; Adeomi, Adeleye A

    2010-01-01

    Nigeria, like most African nations, is basically conservative, but the young people are becoming more sexually liberated, and the incidence of STD/HIV, unwanted pregnancies and abortions among these young people is on the increase. The use of barrier contraception (BC), which is a cost-effective method of preventing STD/HIV, unwanted pregnancies and its attending complications, has therefore become an important issue in reproductive health. This descriptive cross-sectional study was carried out among first year students of Osun State University, Nigeria. Four hundred respondents were studied using pre-tested semi-structured questionnaires. The respondents were selected by balloting. Most respondents (93%) had heard about the male condom as a method of barrier contraception. Most respondents (79.1%) supported the use of barrier contraceptives, but many (62.5%) thought it would promote sexual promiscuity, 33.4% believed that the use of barrier contraception reflected a lack of trust from the partner, and 38.7% felt barrier contraception is not necessary with a stable partner. One hundred and sixty one (40.5%) had used a form of barrier contraception before, but only 130 (32.7%) are currently using BC. The male condom was the most commonly used method (88.2%), followed by female condom and diaphragm (5.6% respectively). The prevention of STI and unwanted pregnancies were the main reasons (59%) given by respondents for using BC, while religion was the main reason given by non-users. The attitudes of these students toward barrier contraception and their practice were poor. The role of sex education at homes and religious gatherings cannot be over-emphasized. PMID:21061934

  8. Correlates of Regular Participation in Sports Groups among Japanese Older Adults: JAGES Cross–Sectional Study

    PubMed Central

    Yamakita, Mitsuya; Kanamori, Satoru; Kondo, Naoki; Kondo, Katsunori

    2015-01-01

    Background Participation in a sports group is key for the prevention of incident functional disability. Little is known about the correlates of older adults’ participation in sports groups, although this could assist with the development of effective health strategies. The purpose of this study was to identify the demographic and biological, psychosocial, behavioral, social and cultural, and environmental correlates of sports group participation among Japanese older adults. Methods Data were obtained from the Japan Gerontological Evaluation study, which was a population–based cohort of people aged ?65 years without disability enrolled from 31 municipalities across Japan (n = 78,002). Poisson regression analysis was used to determine the associations between the factors and participation in sports groups. Results Non-regular participation in sports groups was associated with lower educational level, being employed, and working the longest in the agricultural/forestry/fishery industry among the demographic and biological factors and poor self-rated health and depression among the psychosocial factors. Of the behavioral factors, current smoking was negatively associated and current drinking was positively associated with regular participation in sports groups. Among the social and cultural factors, having emotional social support and participating in hobby clubs, senior citizen clubs, or volunteer groups were associated with a high prevalence of participation in sports groups. Perceptions of the presence of parks or sidewalks, good access to shops, and good accessibility to facilities were positively associated with participation in sports groups among the environmental factors. Conclusions Our study suggests that the promotion of activities that could increase older adults’ participation in sports groups should consider a broad range of demographic and biological, psychosocial, behavioral, social and cultural, and environmental factors. Although future longitudinal studies to elucidate the causal associations are needed, encouraging participation in community groups through social networks might be effective for participation in sports groups. PMID:26512895

  9. Complex Correlation Kohn-T Method of Calculating Total and Elastic Cross Sections. Part 1; Electron-Hydrogen Elastic Scattering

    NASA Technical Reports Server (NTRS)

    Bhatia, A. K.; Temkin, A.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    We report on the first part of a study of electron-hydrogen scattering, using a method which allows for the ab initio calculation of total and elastic cross sections at higher energies. In its general form the method uses complex 'radial' correlation functions, in a (Kohn) T-matrix formalism. The titled method, abbreviated Complex Correlation Kohn T (CCKT) method, is reviewed, in the context of electron-hydrogen scattering, including the derivation of the equation for the (complex) scattering function, and the extraction of the scattering information from the latter. The calculation reported here is restricted to S-waves in the elastic region, where the correlation functions can be taken, without loss of generality, to be real. Phase shifts are calculated using Hylleraas-type correlation functions with up to 95 terms. Results are rigorous lower bounds; they are in general agreement with those of Schwartz, but they are more accurate and outside his error bounds at a couple of energies,

  10. HIV related risk behaviours among taxi drivers and their assistants in Addis Ababa, Ethiopia: descriptive cross-sectional survey

    PubMed Central

    2014-01-01

    Background Risk taking behaviours in relation to HIV among the mobile population is a growing public health concern in many developing countries, including Ethiopia. The aim of this study was to describe risky sexual behaviours and associated factors among male taxi drivers and assistants in Addis Ababa. Methods A descriptive cross-sectional survey design with multistage cluster sampling procedure was employed to select 615 individuals for interview. Results Seventy six percent of the respondents were sexually active. Nearly 31% of the respondents reported casual sex and 7% of them did not use a condom with their most recent casual sex partner. More than half (58.5%) of the respondents had no condom use efficacy. Condom breakage and/or slippage during sex had been encountered by 44% of respondents with casual partners and sex during menstruation had ever occurred among 17% of respondents. Eleven percent had experienced sex with female sex workers. Thirty-three percent of the respondents were unfaithful to their spouse/steady partners. Multivariate analysis revealed that living with parents [AOR 95% CI; 2(1.14-3.60)], non-khat chewers [AOR 95% CI; 3.7(2.13-6.31)], never taken VCT [AOR 95% CI; 3.5(1.84-6.72)], middle-class monthly cash gain [AOR 95% CI; 0.5(0.25-0.98)] and more years of experience working on a taxi [AOR 95% CI; 0.17(0.60-0.47)] were statistically significant to influence lifetime abstinence. Non-khat chewers [AOR 95% CI; 0.53(0.37-0.78)], never taken VCT [AOR 95% CI; 0.54(0.36-0.88)] and higher monthly cash gain [AOR 95% CI; 2.9(1.14-7.19)] had a statistically significant association with condom use efficacy. Living with parents [AOR 95% CI; 2(1.31-3.72)], living with friends [AOR 95% CI; 6.4(3.13-12.89)] and non-khat chewers [AOR 95% CI; 2(1.34-3.53)] were risk factors found to be associated with faithfulness. Conclusions Risky sexual behaviours in this sub-population were considerable and associated factors were found to be multidimensional. Therefore, there is a need for robust intervention strategies such as tailored serial radio program targeting taxi drivers and their assistants. PMID:24712295

  11. Body Image Perceptions of Persons With a Stoma and Their Partners: A Descriptive, Cross-sectional Study.

    PubMed

    Aktas, Dilek; Gocman Baykara, Zehra

    2015-05-01

    The body image perceptions of persons with a stoma and their partners are rarely examined and have yet to be evaluated in a Turkish sample. Using convenience sampling methods, a descriptive, cross-sectional study was conducted among individuals receiving treatment at the authors' stomatherapy unit between March 1, 2012 and May 31, 2012 to assess the effect of the stoma on self-image and partner perception. Eligible participants had to be >18 years of age, married, and with an abdominal stoma (colostomy, urostomy, or ileostomy) for at least 2 months. Data were obtained through separate (patient or partner), face-to-face, 30-minute to 45-minute interviews using the appropriate questionnaire. Questionnaire items assessed demographic variables and patient/partner feelings toward the ostomate's body using the Body Cathexis Scale (BCS) and author-developed questionnaires comprising statements eliciting individual responses (agree, disagree, undecided) regarding their feelings toward the stoma. Data were tabulated and analyzed using percentile distributions, and Mann Whitney U and Kruskal Wallis H tests were performed (Bonferroni correction was applied). Sixty (60) patients (25 women, 35 men, mean age 56.01 ± 10.1 years; 25 with an ileostomy, 30 with a colostomy, 5 with an ileostomy) participated, along with their 60 heterosexual partners (mean age 54.56 ± 10.25 years) married a mean of 33.06 ± 11.03 years. Mean patient BCS score was 133.15 ± 20.58 (range 40--low perception--to 200--high perception). Mean BCS score of patients whose partner helped in stoma care was significantly higher (136.04) than those whose partners did not (120.27) (P = 0.033). Patients who consulted their partners' opinions on stoma creation and participation in care had significantly higher BCS scores (P <0.05), and BCS scores of patients whose partners thought the stoma had a negative effect on their relationship were significantly lower (P = 0.040); patients' perceptions toward their bodies were parallel to their partners'. Mean BCS score of patients experiencing physical and psychosocial problems was significantly lower than those of patients who did not experience such problems. The results of this study show a number of factors, including involving patient partners before surgery, affect body perception of persons following stoma surgery. PMID:25965090

  12. Knowledge of family health program practitioners in Brazil about sickle cell disease: a descriptive, cross-sectional study

    PubMed Central

    2011-01-01

    Background Although sickle cell disease is an important public health problem in Brazil, there is a gap in the literature on the level of knowledge of primary health care professionals about the treatment and management of sickle cell disease. Therefore, this study aimed to evaluate the level of knowledge about sickle cell disease of physicians and nurses who work in the Family Health Program in a region of Brazil with a high prevalence of this disease. Methods This is a descriptive, cross-sectional study conducted at the municipality of Montes Claros, in the north of Minas Gerais, Brazil. Study participants included 96 physicians and nurses who work at the Family Health Program in an urban area of the city. Data was collected using an original, partially tested questionnaire based on health care check points for children with sickle cell disease established in educational protocols from the State Health Secretary of Minas Gerais and the Ministry of Health. The structured questionnaire contained 47 questions addressing three axes: epidemiology (8 questions); clinical manifestations (13 questions); and management of children with sickle cell disease (26 questions). Knowledge was measured through mean correct responses to proposed questions. Ethical principles were respected and this project was approved by the Committee of Ethics in Research. Results 59.4% (57) of the study participants were nurses and 40.6% (39) were physicians. The median length of training and median length of service in primary health care were 4.3 (2.8-8.0) years and 4.0 (2.0-7.1) years, respectively. The mean performance in knowledge tests was < 75%, with 5.7/8 (SD = 1.4) for the "epidemiology" questions; 8.6/13 (SD = 2.2) for "clinical manifestations"; and 17.0/26 (SD = 2.9) for "management of children with sickle cell disease" questions; resulting in a mean total of 31.4/47 (SD = 5.10) correct responses. A statistically significant association was found between the number of correct responses and family health care qualifications (p = 0.015). Conclusion There is an urgent need to improve primary health care professional training in the care of children with sickle cell disease. PMID:21854618

  13. Factors associated with anxiety and depression among type 2 diabetes outpatients in Malaysia: a descriptive cross-sectional single-centre study

    PubMed Central

    Ganasegeran, Kurubaran; Renganathan, Pukunan; Manaf, Rizal Abdul; Al-Dubai, Sami Abdo Radman

    2014-01-01

    Objective To determine the prevalence and factors associated with anxiety and depression among type 2 diabetes outpatients in Malaysia. Design Descriptive, cross-sectional single-centre study with universal sampling of all patients with type 2 diabetes. Setting Endocrinology clinic of medical outpatient department in a Malaysian public hospital. Participants All 169 patients with type 2 diabetes (men, n=99; women, n=70) aged between 18 and 90?years who acquired follow-up treatment from the endocrinology clinic in the month of September 2013. Main outcome measures The validated Hospital Anxiety and Depression Scale (HADS), sociodemographic characteristics and clinical health information from patient records. Results Of the total 169 patients surveyed, anxiety and depression were found in 53 (31.4%) and 68 (40.3%), respectively. In multivariate analysis, age, ethnicity and ischaemic heart disease were significantly associated with anxiety, while age, ethnicity and monthly household income were significantly associated with depression. Conclusions Sociodemographics and clinical health factors were important correlates of anxiety and depression among patients with diabetes. Integrated psychological and medical care to boost self-determination and confidence in the management of diabetes would catalyse optimal health outcomes among patients with diabetes. PMID:24760351

  14. Central Nervous System Idiopathic Inflammatory Demyelinating Disorders in South Americans: A Descriptive, Multicenter, Cross-Sectional Study.

    PubMed

    Papais-Alvarenga, Regina Maria; Vasconcelos, Claudia Cristina Ferreira; Carra, Adriana; de Castillo, Ibis Soto; Florentin, Sara; Diaz de Bedoya, Fernando Hamuy; Mandler, Raul; de Siervi, Luiza Campanella; Pimentel, Maria Lúcia Vellutini; Alvarenga, Marina Papais; Alvarenga, Marcos Papais; Grzesiuk, Anderson Kuntz; Gama Pereira, Ana Beatriz Calmon; Gomes Neto, Antonio Pereira; Velasquez, Carolina; Soublette, Carlos; Fleitas, Cynthia Veronica; Diniz, Denise Sisteroli; Armas, Elizabeth; Batista, Elizabeth; Hernandez, Freda; Pereira, Fernanda Ferreira Chaves da Costa; Siqueira, Heloise Helena; Cabeça, Hideraldo; Sanchez, Jose; Brooks, Joseph Bruno Bidin; Gonçalves, Marcus Vinicius; Barroso, Maria Cristina Del Negro; Ravelo, Maria Elena; Castillo, Maria Carlota; Ferreira, Maria Lúcia Brito; Rocha, Maria Sheila Guimarães; Parolin, Monica Koncke Fiuza; Molina, Omaira; Marinho, Patricia Beatriz Christino; Christo, Paulo Pereira; Brant de Souza, Renata; Pessanha Neto, Silvio; Camargo, Solange Maria das Graças; Machado, Suzana Costa; Neri, Vanderson Carvalho; Fragoso, Yara Dadalti; Alvarenga, Helcio; Thuler, Luiz Claudio Santos

    2015-01-01

    The idiopathic inflammatory demyelinating disease (IIDD) spectrum has been investigated among different populations, and the results have indicated a low relative frequency of neuromyelitis optica (NMO) among multiple sclerosis (MS) cases in whites (1.2%-1.5%), increasing in Mestizos (8%) and Africans (15.4%-27.5%) living in areas of low MS prevalence. South America (SA) was colonized by Europeans from the Iberian Peninsula, and their miscegenation with natives and Africans slaves resulted in significant racial mixing. The current study analyzed the IIDD spectrum in SA after accounting for the ethnic heterogeneity of its population. A cross-sectional multicenter study was performed. Only individuals followed in 2011 with a confirmed diagnosis of IIDD using new diagnostic criteria were considered eligible. Patients' demographic, clinical and laboratory data were collected. In all, 1,917 individuals from 22 MS centers were included (73.7% female, 63.0% white, 28.0% African, 7.0% Mestizo, and 0.2% Asian). The main disease categories and their associated frequencies were MS (76.9%), NMO (11.8%), other NMO syndromes (6.5%), CIS (3.5%), ADEM (1.0%), and acute encephalopathy (0.4%). Females predominated in all main categories. The white ethnicity also predominated, except in NMO. Except in ADEM, the disease onset occurred between 20 and 39 years old, early onset in 8.2% of all cases, and late onset occurred in 8.9%. The long-term morbidity after a mean disease time of 9.28±7.7 years was characterized by mild disability in all categories except in NMO, which was scored as moderate. Disease time among those with MS was positively correlated with the expanded disability status scale (EDSS) score (r=0.374; p=<0.001). This correlation was not observed in people with NMO or those with other NMO spectrum disorders (NMOSDs). Among patients with NMO, 83.2% showed a relapsing-remitting course, and 16.8% showed a monophasic course. The NMO-IgG antibody tested using indirect immunofluorescence (IIF) with a composite substrate of mouse tissues in 200 NMOSD cases was positive in people with NMO (95/162; 58.6%), longitudinally extensive transverse myelitis (10/30; 33.3%) and bilateral or recurrent optic neuritis (8/8; 100%). No association of NMO-IgG antibody positivity was found with gender, age at onset, ethnicity, early or late onset forms, disease course, or long-term severe disability. The relative frequency of NMO among relapsing-remitting MS (RRMS) + NMO cases in SA was 14.0%. Despite the high degree of miscegenation found in SA, MS affects three quarters of all patients with IIDD, mainly white young women who share similar clinical characteristics to those in Western populations in the northern hemisphere, with the exception of ethnicity; approximately one-third of all cases occur among non-white individuals. At the last assessment, the majority of RRMS patients showed mild disability, and the risk for secondary progression was significantly superior among those of African ethnicity. NMO comprises 11.8% of all IIDD cases in SA, affecting mostly young African-Brazilian women, evolving with a recurrent course and causing moderate or severe disability in both ethnic groups. The South-North gradient with increasing NMO and non-white individuals from Argentina, Paraguay, Brazil and Venezuela confirmed previous studies showing a higher frequency of NMO among non-white populations. PMID:26222205

  15. Central Nervous System Idiopathic Inflammatory Demyelinating Disorders in South Americans: A Descriptive, Multicenter, Cross-Sectional Study

    PubMed Central

    Papais-Alvarenga, Regina Maria; Vasconcelos, Claudia Cristina Ferreira; Carra, Adriana; de Castillo, Ibis Soto; Florentin, Sara; Diaz de Bedoya, Fernando Hamuy; Mandler, Raul; de Siervi, Luiza Campanella; Pimentel, Maria Lúcia Vellutini; Alvarenga, Marina Papais; Papais Alvarenga, Marcos; Grzesiuk, Anderson Kuntz; Gama Pereira, Ana Beatriz Calmon; Gomes Neto, Antonio Pereira; Velasquez, Carolina; Soublette, Carlos; Fleitas, Cynthia Veronica; Diniz, Denise Sisteroli; Armas, Elizabeth; Batista, Elizabeth; Hernandez, Freda; Pereira, Fernanda Ferreira Chaves da Costa; Siqueira, Heloise Helena; Cabeça, Hideraldo; Sanchez, Jose; Brooks, Joseph Bruno Bidin; Gonçalves, Marcus Vinicius; Barroso, Maria Cristina Del Negro; Ravelo, Maria Elena; Castillo, Maria Carlota; Ferreira, Maria Lúcia Brito; Rocha, Maria Sheila Guimarães; Parolin, Monica Koncke Fiuza; Molina, Omaira; Marinho, Patricia Beatriz Christino; Christo, Paulo Pereira; Brant de Souza, Renata; Pessanha Neto, Silvio; Camargo, Solange Maria das Graças; Machado, Suzana Costa; Neri, Vanderson Carvalho; Fragoso, Yara Dadalti; Alvarenga, Helcio; Thuler, Luiz Claudio Santos

    2015-01-01

    The idiopathic inflammatory demyelinating disease (IIDD) spectrum has been investigated among different populations, and the results have indicated a low relative frequency of neuromyelitis optica (NMO) among multiple sclerosis (MS) cases in whites (1.2%-1.5%), increasing in Mestizos (8%) and Africans (15.4%-27.5%) living in areas of low MS prevalence. South America (SA) was colonized by Europeans from the Iberian Peninsula, and their miscegenation with natives and Africans slaves resulted in significant racial mixing. The current study analyzed the IIDD spectrum in SA after accounting for the ethnic heterogeneity of its population. A cross-sectional multicenter study was performed. Only individuals followed in 2011 with a confirmed diagnosis of IIDD using new diagnostic criteria were considered eligible. Patients’ demographic, clinical and laboratory data were collected. In all, 1,917 individuals from 22 MS centers were included (73.7% female, 63.0% white, 28.0% African, 7.0% Mestizo, and 0.2% Asian). The main disease categories and their associated frequencies were MS (76.9%), NMO (11.8%), other NMO syndromes (6.5%), CIS (3.5%), ADEM (1.0%), and acute encephalopathy (0.4%). Females predominated in all main categories. The white ethnicity also predominated, except in NMO. Except in ADEM, the disease onset occurred between 20 and 39 years old, early onset in 8.2% of all cases, and late onset occurred in 8.9%. The long-term morbidity after a mean disease time of 9.28±7.7 years was characterized by mild disability in all categories except in NMO, which was scored as moderate. Disease time among those with MS was positively correlated with the expanded disability status scale (EDSS) score (r=0.374; p=<0.001). This correlation was not observed in people with NMO or those with other NMO spectrum disorders (NMOSDs). Among patients with NMO, 83.2% showed a relapsing-remitting course, and 16.8% showed a monophasic course. The NMO-IgG antibody tested using indirect immunofluorescence (IIF) with a composite substrate of mouse tissues in 200 NMOSD cases was positive in people with NMO (95/162; 58.6%), longitudinally extensive transverse myelitis (10/30; 33.3%) and bilateral or recurrent optic neuritis (8/8; 100%). No association of NMO-IgG antibody positivity was found with gender, age at onset, ethnicity, early or late onset forms, disease course, or long-term severe disability. The relative frequency of NMO among relapsing-remitting MS (RRMS) + NMO cases in SA was 14.0%. Despite the high degree of miscegenation found in SA, MS affects three quarters of all patients with IIDD, mainly white young women who share similar clinical characteristics to those in Western populations in the northern hemisphere, with the exception of ethnicity; approximately one-third of all cases occur among non-white individuals. At the last assessment, the majority of RRMS patients showed mild disability, and the risk for secondary progression was significantly superior among those of African ethnicity. NMO comprises 11.8% of all IIDD cases in SA, affecting mostly young African-Brazilian women, evolving with a recurrent course and causing moderate or severe disability in both ethnic groups. The South-North gradient with increasing NMO and non-white individuals from Argentina, Paraguay, Brazil and Venezuela confirmed previous studies showing a higher frequency of NMO among non-white populations. PMID:26222205

  16. Prevalence and Positive Correlates of Posttraumatic Stress Disorder Symptoms among Chinese Patients with Hematological Malignancies: A Cross-Sectional Study

    PubMed Central

    Liu, Li; Yang, Yi-Long; Wang, Zi-Yue; Wu, Hui; Wang, Yang; Wang, Lie

    2015-01-01

    Purpose Positive psychological constructs have been given increasing attention in research on the coping resources of cancer-related distresses. However, little research is available on posttraumatic stress disorder (PTSD) in patients with hematological malignancies. The purposes of this study were to assess the prevalence of PTSD symptoms and to explore the associations of perceived social support (PSS), hope, optimism and resilience with PTSD symptoms among Chinese patients with hematological malignancies. Methods A cross-sectional study was conducted during the period from July 2013 through April 2014. A total of 225 inpatients with hematological malignancies, which were eligible for the study, completed the Post-traumatic Stress Checklist-Civilian Version, Multidimensional Scale of Perceived Social Support, Adult Hope Scale, Life Orientation Scale-Revised, and Resilience Scale. Hierarchical regression analysis was performed to explore the correlates of PTSD symptoms. Results Overall, the prevalence of PTSD symptoms was 10.7%. Initially, PSS was negatively associated with PTSD symptoms (? = -0.248, P < 0.01). However, when positive psychological variables were added, optimism was negatively associated with PTSD symptoms (? = -0.452, P < 0.01), and gender had a significant effect on PTSD symptoms. Women were more vulnerable to these symptoms than men (? = 0.123, P < 0.05). When the analysis was performed separately by gender, only optimism showed a significantly negative association with PTSD symptoms in both men (? = -0.389, P < 0.01) and women (? = -0.493, P < 0.01). Conclusions Some patients with hematological malignancies suffer from PTSD symptoms. The positive effects of PSS and optimism on PTSD symptoms suggest that an integrated approach to psychosocial intervention from both external and internal perspectives could have practical significance. Gender difference should be considered in developing potential interventions in reducing cancer-related PTSD symptoms. PMID:26669841

  17. Clinical and cognitive correlates of employment among patients with schizophrenia: a cross-sectional study in Malaysia

    PubMed Central

    2011-01-01

    Background Gainful employment is one major area of functioning which is becoming an important goal in psychiatric rehabilitation of patients with schizophrenia. Studies in western countries are pointing to evidence that certain sociodemographic and clinical factors may contribute to employment outcomes in this group of people. However, the area is still largely unexplored in Malaysia. The aim of this study was to examine the sociodemographic, clinical and cognitive correlates of employment status among patients with Schizophrenia. Methods This was a cross-sectional study. All participants who fulfilled the requirements of the study according to the inclusion and exclusion criteria were enrolled. Study instruments included a demographic data questionnaire, Positive and Negative Symptom Scale (PANSS), Trail Making Tests, Rey's Auditory Verbal Learning Test (RAVLT) and Digit Span. Bivariate analyses were done using chi-square for categorical data and t-test for continuous data and multiple logistic regression analysis was done to identify predictors of employment status. Results A total of 95 participants who fulfilled the inclusion criteria were enrolled into the study. Among the sociodemographic, clinical and cognitive variables studied marital status, educational level, mean scores of negative symptoms, Digit Span and RAVLT and Trail Making Tests were found to show significant association with employment status on bivariate analyses. However, when entered into a logistic regression model, only cognitive variables ie. Trail A and B, Digit Span and RAVLT were significant predictors of employment status. Conclusions The results from this study support the role of cognitive function, particularly, attention, working memory and executive functioning on attaining and maintaining employment in persons with schizophrenia as measured by the RAVLT, Digit Span and Trail Making Tests. These findings may act as preliminary evidence suggesting the importance of integrating cognitive rehabilitation in the psychosocial rehabilitation program for patients with schizophrenia in Malaysia. PMID:21624111

  18. Depressive symptoms and alcohol correlates among Brazilians aged 14 years and older: a cross-sectional study

    PubMed Central

    2014-01-01

    Background The associations between depressive symptoms and alcohol-related disorders, drinking patterns and other characteristics of alcohol use are important public health issues worldwide. This study aims to study these associations in an upper middle-income country, Brazil, and search for related socio-demographic correlations in men and women. Methods A cross-sectional study was conducted between November 2005 and April 2006. The sample of 3,007 participants, selected using a multistage probabilistic sampling method, represents the Brazilian population aged 14 and older. Depressive symptoms were assessed using the Center for Epidemiologic Studies Depression Scale and alcohol dependence was assessed using the Composite International Diagnostic Interview. Associations assessed using bi-variate analysis were tested using Rao-Scott measures. Gender specific multinomial logistic regression models were developed. Results Among the participants with alcohol dependence, 46% had depressive symptoms (17.2% mild/moderate and 28.8% major/severe; p?

  19. Description of Light Ion Production Cross Sections and Fluxes on the Mars Surface using the QMSFRG Model

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Kim, Myung-Hee; Schneider, Irene; Hassler, Donald M.

    2006-01-01

    The atmosphere of Mars significantly attenuates the heavy ion component of the primary galactic cosmic rays (GCR), however increases the fluence of secondary light ions (neutrons, and hydrogen and helium isotopes) because of particle production processes. We describe results of the quantum multiple scattering fragmentation (QMSFRG) model for the production of light nuclei through the distinct mechanisms of nuclear abrasion and ablation, coalescence, and cluster knockout. The QMSFRG model is shown to be in excellent agreement with available experimental data for nuclear fragmentation cross sections. We use the QMSFRG model and the space radiation transport code, HZETRN to make predictions of the light particle environment on the Martian surface at solar minimum and maximum. The radiation assessment detector (RAD) experiment will be launched in 2009 as part of the Mars Science Laboratory (MSL). We make predictions of the expected results for time dependent count-rates to be observed by RAD experiment. Finally, we consider sensitivity assessments of the impact of the Martian atmospheric composition on particle fluxes at the surface.

  20. Socio-demographic, medical and social-cognitive correlates of physical activity behavior among older adults (45–70 years): a cross-sectional study

    PubMed Central

    2014-01-01

    Background Present study aimed to identify socio-demographic, medical and social-cognitive correlates of physical activity among Dutch older individuals. Methods A systematic random sample of 2,568 Dutch participants aged 45–70 years filled out the validated modified Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire on physical activity. Socio-demographic and social-cognitive correlates were measured with validated instruments; medical correlates were checked by a general practitioner. The study had a cross-sectional design and the data collection ran from March 2005 until August 2006. Linear regression analyses were conducted to identify correlates of PA. We separated the findings for men from those for women to explore potential gender-specific associations. Results Being female, living in North Limburg or North-Brabant, having a higher educational level, a higher perceived behavioral control, more knowledge about PA advantages, a stronger habitual PA behavior, having more action plans and a stronger intention to engage in PA were significantly associated with higher PA levels. Being older, being a smoker, having a higher body mass index (BMI), having a paid job, observing others being physically active and overestimating one's PA level were associated with being less physically active. Socio-demographic and medical correlates significantly explained 20% of the variance of PA behavior while social-cognitive correlates as attitude explained an additional 4% and intention together with actual control explained another 1% of the variance of PA behavior. Conclusion There may be stable individual differences that influence PA in view of the fact that several socio-demographic and medical factors were not completely mediated by the socio-cognitive factors. The current study may help to focus PA interventions for individuals aged 45–70 years on influential socio-demographic, medical and social-cognitive correlates. Physical activity was significantly associated with age, gender, education, BMI, work situation, region of residence, smoking, awareness, advantages, descriptive norm, perceived behavioral control, habit, action plans and intention. PMID:24965940

  1. Descriptive epidemiology and high risk behavior of male prescription opioid abusers: Cross-sectional study from Sikkim, North East India

    PubMed Central

    Datta, D.; Pandey, S.; Dutta, S.; Verma, Y.; Chakrabarti, Amit

    2015-01-01

    Background: Sikkim is emerging as an important area for prescription opioid abuse with frequent news of seizures and arrests due to possession of prescription opioids. However, till date there is a little information on descriptive epidemiology and high risk behavior of prescription opioid abusers from Sikkim. Aims: The aim was to describe demographic (age, sex, religion, marital status, community, occupation, etc.); socioeconomic (income, education, family information etc.); and high risk behavior (e.g., injection sharing, visit to commercial sex workers [CSWs], homosexuality etc.) among treatment-seeking prescription opioid abusers in Sikkim. Materials and Methods: Epidemiological data were collected by administering predevised questionnaires from n = 223 prescription opioid abusers (main problem prescription opioids) reporting for treatment at five different drug abuse treatment centers across Sikkim. Results: The mean age of prescription opioid abusers in Sikkim was 27 years; all were male, of Nepalese ethnicity and single/never married, school dropout and/or illiterate, earning < Rs. 10,000/month with most spending almost Rs. 5000 a month on prescription opioids. Most (57.4%) prescription opioid abusers belonged to the urban community. Commonly abused prescription opioids were dextropropoxyphene and codeine. Injection sharing was more in urban areas whereas syringe exchange was observed equally among rural and urban prescription opioid abusers. Among urban injectors visits to CSWs, and multiple sex partners were also common in spite of knowledge about AIDS. Limited condom use was observed among rural respondents. Incidences of arrests, public intoxication, and violence under the influence of prescription opioids were also reported. Conclusion: Both the rural and urban areas of Sikkim show increasing rates of prescription opioid abuse among males. It is more prevalent among school dropouts and unemployed youth. Trends of injection drug use, unsafe injection, high risk behavior have also been observed. PMID:26600583

  2. Social relationship correlates of major depressive disorder and depressive symptoms in Switzerland: nationally representative cross sectional study

    PubMed Central

    2014-01-01

    Background The quality and quantity of social relationships are associated with depression but there is less evidence regarding which aspects of social relationships are most predictive. We evaluated the relative magnitude and independence of the association of four social relationship domains with major depressive disorder and depressive symptoms. Methods We analyzed a cross-sectional telephone interview and postal survey of a probability sample of adults living in Switzerland (N?=?12,286). Twelve-month major depressive disorder was assessed via structured interview over the telephone using the Composite International Diagnostic Interview (CIDI). The postal survey assessed depressive symptoms as well as variables representing emotional support, tangible support, social integration, and loneliness. Results Each individual social relationship domain was associated with both outcome measures, but in multivariate models being lonely and perceiving unmet emotional support had the largest and most consistent associations across depression outcomes (incidence rate ratios ranging from 1.55-9.97 for loneliness and from 1.23-1.40 for unmet support, p’s?

  3. Prevalence and correlates of hyperglycemia in a rural population, Vietnam: implications from a cross–sectional study

    PubMed Central

    2012-01-01

    Background Despite the increasing prevalence of type 2 diabetes in urban areas, relatively little has been known about its actual prevalence and its associations in rural areas, Vietnam. The purpose of this study was to evaluate the prevalence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), diabetes and their risk factors in a rural province, Vietnam. Methods A cross–sectional study with a representative sample was designed to estimate the hyperglycemia prevalence, using 75–g oral glucose tolerance test. Potential risk factors for hyperglycemia were analyzed using multinomial logistic regression, taken into account influences of socio–economic status, anthropometric measures, and lifestyle–related factors. Results The age and sex–adjusted prevalence rates (95% CI) of isolated IFG, isolated IGT, combined IFG–IGT, and diabetes were 8.7 (7.0–10.5), 4.3 (3.2?5.4), 1.6 (0.9?2.3), and 3.7% (2.7–4.7%), respectively. There were still 73% of diabetic subjects without knowing the condition. Blood pressure, family history of diabetes, obesity–related measures (waist circumference, waist–hip ratio, body fat percentage, and abdominal obesity) were the independent risk factors for hyperglycemia (IFG, IGT, and diabetes). Conclusions The prevalence of hyperglycemia in rural areas has not been as sharply increased as that reported in urban cities, Vietnam. Blood pressure and obesity–related measures were the most significant predictors for hyperglycemia level and they can be taken into account in building prognosis models to early detection of diabetes in rural Vietnamese populations. PMID:23114020

  4. Correlation between basic physical fitness and pulmonary function in Korean children and adolescents: a cross-sectional survey

    PubMed Central

    Bae, Ju Yong; Jang, Ki Sung; Kang, Sunghwun; Han, Don Hee; Yang, Wonho; Shin, Ki Ok

    2015-01-01

    [Purpose] The purpose of the present study was to determine whether there was a correlation between basic physical fitness and pulmonary function in Korean school students, to present an alternative method for improving their pulmonary function. [Subjects and Methods] Two hundred forty healthy students aged 6–17?years performed physical fitness tests of hand-grip strength, sit and reach, Sargent jump, single leg stance, and pulmonary function tests of forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) using a Quark PFT. [Results] Muscle strength and power of boys improved in the late period of elementary school and middle school. Muscle strength of girls improved in the late period of elementary school. Analysis of factors affecting pulmonary function revealed that height, weight, BMI, and body fat significantly correlated with spirometric parameters. Right hand-grip strength, left hand-grip strength, and Sargent jump also significantly correlated with FVC and FEV1. [Conclusion] In order to improve the pulmonary function of children and adolescents, aerobic exercise and an exercise program to increase muscle strength and power is needed, and it should start in the late period of elementary school when muscle strength and power are rapidly increasing. PMID:26504269

  5. Correlation of Skin Changes with Hormonal Changes in Polycystic Ovarian Syndrome: A Cross-sectional Study Clinical Study

    PubMed Central

    Gowri, B Vijaya; Chandravathi, PL; Sindhu, PS; Naidu, K Shanthi

    2015-01-01

    Background: Polycystic ovarian syndrome (PCOS) is a heterogenous collection of signs and symptoms that when gathered, form a spectrum of disorder with disturbance of reproductive, endocrine and metabolic functions. Aim: The aim of this study is to correlate the skin manifestations with hormonal changes and to know the incidence and prevalence of skin manifestations in patients with PCOS. Materials and Methods: A total of 40 patients with PCOS were examined during 1 year time period from May 2008 P to May 2009. Detailed clinical history was taken from each patient. PCOS was diagnosed on the basis of ultrasonography. Hormonal assays included fasting blood sugar, postprandial blood sugar, follicle-stimulating hormone, luteinizing hormone, thyroid stimulating hormone, dehydroepiandrostenedione, prolactin, free testosterone, fasting lipid profile and sex hormone binding globulin. The results obtained were statistically correlated. Results: In our study, the prevalence of cutaneous manifestations was 90%. Of all the cutaneous manifestations acne was seen in highest percentage (67.5%), followed by hirsutism (62.5%), seborrhea (52.5%), androgenetic alopecia (AGA) (30%), acanthosis nigricans (22.5%) and acrochordons (10%). Fasting insulin levels was the most common hormonal abnormality seen in both acne and hirsutism, whereas AGA was associated with high testosterone levels. Conclusion: The prevalence of cutaneous manifestations in PCOS was 90%. Hirsutism, acne, seborrhea, acanthosis nigricans and acrochordons were associated with increased levels of fasting insulin, whereas AGA showed higher levels of serum testosterone. PMID:26288423

  6. Cross-sectional correlation of single-item health literacy screening questions with established measures of health literacy in patients with rheumatoid arthritis.

    PubMed

    Quinzanos, Itziar; Hirsh, Joel M; Bright, Christina; Caplan, Liron

    2015-09-01

    Research suggests that health literacy (HL) is associated with rheumatoid arthritis (RA) patients' functional status. Single-item health literacy screening (SILS) questionnaires may establish patients' HL; however, the wording of SILS may be misinterpreted by RA patients as a query regarding physical limitations. Despite this threat to validity, multiple publications have employed the SILSs as a measure of health literacy. We assessed the construct validity of two SILS's versions by correlating scores with standardized HL measures. English-speaking adult RA patients at a hospital serving low-income patients were enrolled in a cross-sectional study. Subjects completed two SILS versions, as well as two longer HL measurement tools [short test of functional health literacy in adults (s-TOFHLA) and the rapid estimate of adult literacy in medicine (REALM)]. Spearman correlation was used to compare these tools. The study enrolled 110 subjects. There was a good correlation between the two SILS versions (r = 0.705). The correlation of SILS2 and REALM or s-TOFHLA was less robust. The distribution of scores within each SILS2 category demonstrated substantial variation. The SILS2 has construct validity in the assessment of HL in patients with RA, though its correlation with traditional methods of assessing HL is weak. PMID:25744280

  7. Individual, social, environmental, and physical environmental correlates with physical activity among Canadians: a cross-sectional study.

    TOXLINE Toxicology Bibliographic Information

    Pan SY; Cameron C; Desmeules M; Morrison H; Craig CL; Jiang X

    2009-01-01

    BACKGROUND: The identification of various individual, social and physical environmental factors affecting physical activity (PA) behavior in Canada can help in the development of more tailored intervention strategies for promoting higher PA levels in Canada. This study examined the influences of various individual, social and physical environmental factors on PA participation by gender, age and socioeconomic status, using data from the 2002 nationwide survey of the Physical Activity Monitor.METHODS: In 2002, 5,167 Canadians aged 15-79 years, selected by random-digit dialling from household-based telephone exchanges, completed a telephone survey. The short version of the International Physical Activity Questionnaire was used to collect information on total physical activity. The effects of socio-economical status, self-rated health, self-efficacy, intention, perceived barriers to PA, health benefits of PA, social support, and facility availability on PA level were examined by multiple logistic regression analyses.RESULTS: Self-efficacy and intention were the strongest correlates and had the greatest effect on PA. Family income, self-rated health and perceived barriers were also consistently associated with PA. The effects of the perceived health benefits, education and family income were more salient to older people, whereas the influence of education was more important to women and the influence of perceived barriers was more salient to women and younger people. Facility availability was more strongly associated with PA among people with a university degree than among people with a lower education level. However, social support was not significantly related to PA in any subgroup.CONCLUSION: This study suggests that PA promotion strategies should be tailored to enhance people's confidence to engage in PA, motivate people to be more active, educate people on PA's health benefits and reduce barriers, as well as target different factors for men and women and for differing socio-economic and demographic groups.

  8. Serum Ferritin Is Inversely Correlated with Testosterone in Boys and Young Male Adolescents: A Cross-Sectional Study in Taiwan

    PubMed Central

    Chao, Kuo-Ching; Chang, Chun-Chao; Chiou, Hung-Yi; Chang, Jung-Su

    2015-01-01

    Objective The transition from childhood to teenaged years is associated with increased testosterone and a decreased iron status. It is not clear whether higher testosterone levels cause the decreased iron status, and to what extent, obesity-related inflammation influences the iron-testosterone relationship. The aim of the present study was to examine relationships of testosterone, iron status, and anti-/proinflammatory cytokines in relation to nutritional status in boys and young adolescent Taiwanese males. Methods In total, 137 boys aged 7~13 yr were included. Parameters for obesity, the iron status, testosterone, and inflammatory markers were evaluated. Results Overweight and obese (ow/obese) boys had higher mean serum testosterone, interleukin (IL)-1?, and nitric oxide (NO) levels compared to their normal-weight counterparts (all p<0.05). Mean serum ferritin was slightly higher in ow/obese boys compared to normal-weight boys, but this did not reach statistical significance. A multiple linear regression showed that serum ferritin (? = -0.7470, p = 0.003) was inversely correlated with testosterone, while serum IL-10 (? = 0.3475, p = 0.009) was positively associated with testosterone after adjusting for covariates. When normal-weight boys were separately assessed from ow/obesity boys, the association between testosterone and serum ferritin became stronger (? = -0.9628, p<0.0001), but the association between testosterone and IL-10 became non-significant (? = 0.1140, p = 0.4065) after adjusting for covariates. In ow/obese boys, only IL-10 was weakly associated with serum testosterone (? = 0.6444, p = 0.051) after adjusting for age. Conclusions Testosterone and serum ferritin are intrinsically interrelated but this relationship is weaker in ow/obese boys after adjusting for age. PMID:26646112

  9. The Correlation between Running Economy and Maximal Oxygen Uptake: Cross-Sectional and Longitudinal Relationships in Highly Trained Distance Runners

    PubMed Central

    Shaw, Andrew J.; Ingham, Stephen A.; Atkinson, Greg; Folland, Jonathan P.

    2015-01-01

    A positive relationship between running economy and maximal oxygen uptake (V?O2max) has been postulated in trained athletes, but previous evidence is equivocal and could have been confounded by statistical artefacts. Whether this relationship is preserved in response to running training (changes in running economy and V?O2max) has yet to be explored. This study examined the relationships of (i) running economy and V?O2max between runners, and (ii) the changes in running economy and V?O2max that occur within runners in response to habitual training. 168 trained distance runners (males, n = 98, V?O2max 73.0 ± 6.3 mL?kg-1?min-1; females, n = 70, V?O2max 65.2 ± 5.9 mL kg-1?min-1) performed a discontinuous submaximal running test to determine running economy (kcal?km-1). A continuous incremental treadmill running test to volitional exhaustion was used to determine V?O2max 54 participants (males, n = 27; females, n = 27) also completed at least one follow up assessment. Partial correlation analysis revealed small positive relationships between running economy and V?O2max (males r = 0.26, females r = 0.25; P<0.006), in addition to moderate positive relationships between the changes in running economy and V?O2max in response to habitual training (r = 0.35; P<0.001). In conclusion, the current investigation demonstrates that only a small to moderate relationship exists between running economy and V?O2max in highly trained distance runners. With >85% of the variance in these parameters unexplained by this relationship, these findings reaffirm that running economy and V?O2max are primarily determined independently. PMID:25849090

  10. On your bike! a cross-sectional study of the individual, social and environmental correlates of cycling to school

    PubMed Central

    2011-01-01

    Background Active school transport (AST) has declined rapidly in recent decades. While many studies have examined walking, cycling to school has received very little attention. Correlates of cycling are likely to differ to those from walking and cycling enables AST from further distances. This study examined individual, social and environmental factors associated with cycling to school among elementary school-aged children, stratified by gender. Methods Children (n = 1197) attending 25 Australian primary schools located in high or low walkable neighborhoods, completed a one-week travel diary and a parent/child questionnaire on travel habits and attitudes. Results Overall, 31.2% of boys and 14.6% of girls cycled ? 1 trip/week, however 59.4% of boys and 36.7% of girls reported cycling as their preferred school transport mode. In boys (but not girls), school neighborhood design was significantly associated with cycling: i.e., boys attending schools in neighborhoods with high connectivity and low traffic were 5.58 times more likely to cycle (95% CI 1.11-27.96) and for each kilometer boys lived from school the odds of cycling reduced by 0.70 (95% CI 0.63-0.99). Irrespective of gender, cycling to school was associated with parental confidence in their child's cycling ability (boys: OR 10.39; 95% CI 3.79-28.48; girls: OR 4.03; 95% CI 2.02-8.05), parental perceived convenience of driving (boys: OR 0.42; 95% CI 0.23-0.74; girls: OR 0.40; 95% CI 0.20-0.82); and child's preference to cycle (boys: OR 5.68; 95% CI 3.23-9.98; girls: OR 3.73; 95% CI 2.26-6.17). Conclusion School proximity, street network connectivity and traffic exposure in school neighborhoods was associated with boys (but not girls) cycling to school. Irrespective of gender, parents need to be confident in their child's cycling ability and must prioritize cycling over driving. PMID:22074261

  11. Correlates of condom use among female sex workers in The Gambia: results of a cross-sectional survey

    PubMed Central

    Lei, Esther L.; Ketende, Sosthenes C.; Peitzmeier, Sarah; Mason, Krystal; Ceesay, Nuha; Diouf, Daouda; Drame, Fatou Maria; Loum, Jaegan; Papworth, Erin; Baral, Stefan

    2015-01-01

    Objectives. This study examined correlates of condom use among 248 female sex workers (FSW) in The Gambia. Methods. Between July and August 2011, FSW in The Gambia who were older than 16 years of age, the age of consent in The Gambia, were recruited for the study using venue-based sampling and snowball sampling, beginning with seeds who were established clients with the Network of AIDS Services Organizations. To be eligible, FSW must have reported selling sex for money, favors, or goods in the past 12 months. Bivariate and multivariate logistic regressions were used to determine associations and the relative odds of the independent variables with condom use. Four different condom use dependent variables were used: consistent condom use in the past six months during vaginal or anal sex with all clients and partners; consistent condom use in the past month during vaginal sex with new clients; consistent condom use in the past month during vaginal sex with nonpaying partners (including boyfriends, husbands, or casual sexual partners); and condom use at last vaginal or anal sex with a nonpaying partner. Results. Many FSW (67.34%, n = 167) reported it was not at all difficult to negotiate condom use with clients in all applicable situations, and these FSW were more likely to report consistent condom use with all clients and partners in the past 6 months (aOR 3.47, 95% CI [1.70–7.07]) compared to those perceiving any difficulty in condom negotiation. In addition, FSW were more likely to report using condoms in the past month with new clients (aOR 8.04, 95% CI [2.11–30.65]) and in the past month with nonpaying partners (aOR 2.93, 95% CI [1.09–7.89]) if they had been tested for HIV in the past year. Women who bought all their condoms were less likely than those who received all of their condoms for free (aOR 0.38, 95% CI [0.15–0.97]) to have used a condom at last vaginal or anal sex with a nonpaying partner. Conclusions. HIV and sexually transmitted infection (STI) prevention interventions for FSW should aim to improve condom negotiation self-efficacy since women who report less difficulty negotiating condom use are more likely to use condoms with clients. Interventions should also be aimed at structural issues such as increasing access to free condoms and HIV testing since these were positively associated with condom use among FSW. PMID:26290781

  12. Prevalence of thyroid dysfunction and its correlation with CD4 count in newly-diagnosed HIV-positive adults - a cross-sectional study.

    PubMed

    Dev, Nishanth; Sahoo, Ratnakar; Kulshreshtha, Bindu; Gadpayle, A K; Sharma, S C

    2015-11-01

    Prevalence of subclinical hypothyroidism in HIV-positive patients is reported to be high in those with severe immune deficiency. However, there is paucity of literature in newly-diagnosed HIV-positive population. Our aim was to estimate the prevalence of thyroid dysfunction and study its correlation with CD4 count in this population. In this cross-sectional study, patients presenting to the antiretroviral therapy clinic were screened with thyroid function tests, including thyroid stimulating hormone, free triiodothyronine, free thyroxine, and anti-thyroid peroxidase antibody levels at the time of diagnosis. Two hundred and twenty-five HIV-positive and an equal number of healthy volunteers were enrolled. The mean (SD) CD4 count in the study group was 147.1 (84) and 70.7% had advanced immune deficiency with CD4 count <200?cells/µL. The overall prevalence of thyroid dysfunction was 75.5% in the study group and 16% in the control group. Subclinical hypothyroidism was the commonest abnormality noted in almost 53%. Significant correlation was observed between CD4 count and thyroid stimulating hormone, free triiodothyronine, and free thyroxine levels (r?=?-0.86, r?=?0.77, and r?=?0.84, respectively, p?correlates well with declining CD4 counts. PMID:25505045

  13. Pre-hospital care among victims of road traffic accident in a rural area of Tamil Nadu: A cross-sectional descriptive study

    PubMed Central

    Shrivastava, Saurabh R.; Pandian, Pradeep; Shrivastava, Prateek S.

    2014-01-01

    Background: The World Health Organization has estimated that globally almost 1.24 million people die annually on the world's roads. The aim of the study was to assess the attributes of pre-hospital care in road traffic accidents (RTAs) victim brought to the health care establishment and to evaluate the pre-hospital trauma care provided in the rural areas of Kancheepuram district of Tamil Nadu. Materials and Methods: A cross-sectional descriptive study of 3 months duration (June 2014 to August 2014) was conducted in the Shri Sathya Sai Medical College and Research Institute, Kancheepuram. The method of sampling was universal sampling and all RTA victims satisfying the inclusion criteria were included in the study. During the entire study duration, total 200 RTA victims were included. A pre-tested semi-structured questionnaire was used to elicit the desired information after the victims of RTAs are stabilized. Ethical clearance was obtained from the Institutional Ethics Committee prior to the start of the study. Written informed consent was obtained from the study participants (patient/guardian of children) before obtaining any information from them. Data entry and statistical analysis were done using SPSS version 18. Frequency distributions and percentages were computed for all the variables. Results: Majority of the RTA victims 158 (79%) were from the age-group of 15-45 years. Most of the accidents were reported in night time [77 (38.5%)], on week-ends [113 (56.5%)], and involved two-wheelers [153 (76.5%)]. Almost 66 (33%) of the victims were not aware of the existence of emergency ambulance services. Also, only 15 (7.5%) victims were brought to the hospital in the emergency ambulance, of which only 3 victims were accompanied by a doctor. Conclusion: To conclude, the study indicates that a significant proportion of people were unaware about the emergency trauma ambulance services and the existing pre-hospital care services lack in multiple dimensions in a rural area of South India. PMID:25540536

  14. Shuttle orbiter radar cross-sectional analysis

    NASA Technical Reports Server (NTRS)

    Cooper, D. W.; James, R.

    1979-01-01

    Theoretical and model simulation studies on signal to noise levels and shuttle radar cross section are described. Pre-mission system calibrations, system configuration, and postmission system calibration of the tracking radars are described. Conversion of target range, azimuth, and elevation into radar centered east north vertical position coordinates are evaluated. The location of the impinging rf energy with respect to the target vehicles body axis triad is calculated. Cross section correlation between the two radars is presented.

  15. A social ecological approach to understanding correlates of lifetime sexual assault among sexual minority women in Toronto, Canada: results from a cross-sectional internet-based survey

    PubMed Central

    Logie, C. H.; Alaggia, R.; Rwigema, M. J.

    2014-01-01

    Stigma, discrimination and violence contribute to health disparities among sexual minorities. Lesbian, bisexual and queer (LBQ) women experience sexual violence at similar or higher rates than heterosexual women. Most research with LBQ women, however, has focused on measuring prevalence of sexual violence rather than its association with health outcomes, individual, social and structural factors. We conducted a cross-sectional online survey with LBQ women in Toronto, Canada. Multivariate logistic regression analyses were conducted to assess correlates of lifetime sexual assault (LSA). Almost half (42%) of participants (n = 415) reported experiences of LSA. Participants identifying as queer were more likely to have experienced LSA than those identifying as lesbian. When controlling for socio-demographic characteristics, experiencing LSA was associated with higher rates of depression, sexually transmitted infections (STIs), receiving an STI test, belief that healthcare providers were not comfortable with their LBQ sexual orientation, and sexual stigma (overall, perceived and enacted). A history of sexual violence was associated with lower: self-rated health, overall social support, family social support and self-esteem. This research highlights the salience of a social ecological framework to inform interventions for health promotion among LBQ women and to challenge sexual stigma and sexual violence. PMID:24412812

  16. Serum vitamin D3 level inversely correlates with uterine fibroid volume in different ethnic groups: a cross-sectional observational study

    PubMed Central

    Sabry, Mohamed; Halder, Sunil K; Allah, Abdou S Ait; Roshdy, Eman; Rajaratnam, Veera; Al-Hendy, Ayman

    2013-01-01

    Purpose Currently there is no effective medicinal treatment for uterine fibroids (UFs), a common health disorder that affects women of reproductive age. Identification of modifiable risk factors such as vitamin D (Vit D) deficiency could help develop novel strategies for the prevention and/or treatment of UFs. The purpose of this study was to identify whether low serum Vit D3 levels correlate with increased risk of UFs. Methods A total of 154 premenopausal women were recruited for this cross-sectional study. The control group comprised 50 subjects with a normal, fibroid-free uterine structure, confirmed by transvaginal ultrasonography. The 104 case subjects had at least one fibroid lesion that was 2 cm3 in volume or larger, confirmed by transvaginal ultrasonography. For each case subject, total uterine volume and total volume of all existing fibroids were measured in three perpendicular planes, with volume determined according to the prolate ellipse formula (a × b × c × 0.523), where a is height, b is width, and c is depth. Serum Vit D [25(OH) D3] levels were measured by radioimmunoassay. The independent t-test was used to compare serum Vit D levels across groups. Correlations were assessed by Spearman’s rank correlation test. Results Lower serum 25-(OH) Vit D levels were significantly associated with the occurrence of UFs (P = 0.01). A statistically significant inverse correlation was also observed between serum 25-(OH) Vit D levels and total UF volume (r = ?0.31; P = 0.002) within the case cohort. Subjects with larger fibroid volumes had lower serum Vit D levels and vice versa. Data stratified for ethnicity showed a statistically significant inverse correlation between serum 25-(OH) Vit D levels and total fibroid volume in black subjects (r = ?0.42; P = 0.001). An inverse correlation was also evident in white subjects (r = ?0.86; P = 0.58) but this did not reach statistical significance. Conclusion Lower serum Vit D levels are inversely correlated with UF burden in different ethnic groups. Vit D deficiency is a possible risk factor for the occurrence of UFs. PMID:23467803

  17. Cross sections from dipmeter data

    SciTech Connect

    Etchecopar, A.; Bonnetain, J.L. )

    1992-05-01

    This paper describes two computer methods for constructing cross sections from dipmeter data. These methods provide fast and accurate descriptions of the different structures in the vicinity of the well whatever their scales. Thus, it becomes possible to examine both structure at the seismic scale and microstructures such as slumps or microfaults. The methods described are based on two fundamental behaviors of stratified rocks during deformation: similar folding and parallel folding. The similar-fold method is robust and can be used whatever the structure because, in a first approximation, folds, drags, and rollovers can be described as similar folds or parts of similar folds. On the other hand, the parallel-fold method, which is usable only for fold description, is sometimes unstable, although it provides more accurate results. After a description and a comparison of the two methods, examples from different structural environments are examined. It is shown that it is possible to obtain maps and three-dimensional descriptions that can be used as models for synthetic seismic or to evaluate volumes.

  18. Prevalence and Correlates of Bacterial Vaginosis in Different Sub-Populations of Women in Sub-Saharan Africa: A Cross-Sectional Study

    PubMed Central

    Jespers, Vicky; Crucitti, Tania; Menten, Joris; Verhelst, Rita; Mwaura, Mary; Mandaliya, Kishor; Ndayisaba, Gilles F.; Delany-Moretlwe, Sinead; Verstraelen, Hans; Hardy, Liselotte; Buvé, Anne; van de Wijgert, Janneke

    2014-01-01

    Background Clinical development of vaginally applied products aimed at reducing the transmission of HIV and other sexually transmitted infections, has highlighted the need for a better characterisation of the vaginal environment. We set out to characterise the vaginal environment in women in different settings in sub-Saharan Africa. Methods A longitudinal study was conducted in Kenya, Rwanda and South-Africa. Women were recruited into pre-defined study groups including adult, non-pregnant, HIV-negative women; pregnant women; adolescent girls; HIV-negative women engaging in vaginal practices; female sex workers; and HIV-positive women. Consenting women were interviewed and underwent a pelvic exam. Samples of vaginal fluid and a blood sample were taken and tested for bacterial vaginosis (BV), HIV and other reproductive tract infections (RTIs). This paper presents the cross-sectional analyses of BV Nugent scores and RTI prevalence and correlates at the screening and the enrolment visit. Results At the screening visit 38% of women had BV defined as a Nugent score of 7–10, and 64% had more than one RTI (N. gonorrhoea, C. trachomatis, T. vaginalis, syphilis) and/or Candida. At screening the likelihood of BV was lower in women using progestin-only contraception and higher in women with more than one RTI. At enrolment, BV scores were significantly associated with the presence of prostate specific antigen (PSA) in the vaginal fluid and with being a self-acknowledged sex worker. Further, sex workers were more likely to have incident BV by Nugent score at enrolment. Conclusions Our study confirmed some of the correlates of BV that have been previously reported but the most salient finding was the association between BV and the presence of PSA in the vaginal fluid which is suggestive of recent unprotected sexual intercourse. PMID:25289640

  19. International Evaluation of Neutron Cross Section Standards

    SciTech Connect

    Carlson, A.D. , E-Mail: allan.carlson@nist.gov; Pronyaev, V.G.; Smith, D.L.; Larson, N.M.; Chen, Zhenpeng; Hale, G.M.; Hambsch, F.-J.; Gai, E.V.; Oh, Soo-Youl; Badikov, S.A.; Kawano, T.; Hofmann, H.M.

    2009-12-15

    Neutron cross section standards are the basis for the determination of most neutron cross sections. They are used for both measurements and evaluations of neutron cross sections. Not many cross sections can be obtained absolutely - most cross sections are measured relative to the cross section standards and converted using evaluations of the standards. The previous complete evaluation of the neutron cross section standards was finished in 1987 and disseminated as the NEANDC/INDC and ENDF/B-VI standards. R-matrix model fits for the light elements and non-model least-squares fits for all the cross sections in the evaluation were the basis of the combined fits for all of the data. Some important reactions and constants are not standards, but they assist greatly in the determination of the standard cross sections and reduce their uncertainties - these data were also included in the combined fits. The largest experimental database used in the evaluation was prepared by Poenitz and included about 400 sets of experimental data with covariance matrices of uncertainties that account for all cross-energy, cross-reaction and cross-material correlations. For the evaluation GMA, a least-squares code developed by Poenitz, was used to fit all types of cross sections (absolute and shape), their ratios, spectrum-averaged cross sections and thermal constants in one full analysis. But, the uncertainties derived in this manner, and especially those obtained in the R-matrix model fits, have been judged to be too low and unrealistic. These uncertainties were substantially increased prior to their release in the recommended data files of 1987. Modified percentage uncertainties were reassigned by the United States Cross Section Evaluation Working Group's Standards Subcommittee for a wide range of energies, and no covariance (or correlation) matrices were supplied at that time. The need to re-evaluate the cross section standards is based on the appearance of a significant amount of precise experimental data and improved developments in the methodology of analysis and evaluation. Initial efforts to produce a new evaluation were made by the United States Cross Section Evaluation Working Group which formed a Task Force. It was realized that international cooperation would be needed to produce the evaluation. The Working Party on International Evaluation Cooperation of the Nuclear Energy Agency Nuclear Science Committee formed a Subgroup, and the International Atomic Energy Agency formed a Coordinated Research Project (CRP). These groups worked cooperatively to improve the evaluation process. The major effort in producing the evaluation was through the CRP. The evaluations of the neutron cross section standards were finalized in October 2005. Previous difficulties experienced with a data evaluation problem known as 'Peelle's Pertinent Puzzle' create biases in the fit of correlated data, and they have been addressed to reduce this phenomenon. The new evaluations of the cross section standards also include covariance matrices of the uncertainties that contain fully justifiable values. The product of this international effort has been adopted as the neutron standards for ENDF/B-VII.0.

  20. International Evaluation of Neutron Cross Section Standards

    NASA Astrophysics Data System (ADS)

    Carlson, A. D.; Pronyaev, V. G.; Smith, D. L.; Larson, N. M.; Chen, Zhenpeng; Hale, G. M.; Hambsch, F.-J.; Gai, E. V.; Oh, Soo-Youl; Badikov, S. A.; Kawano, T.; Hofmann, H. M.; Vonach, H.; Tagesen, S.

    2009-12-01

    Neutron cross section standards are the basis for the determination of most neutron cross sections. They are used for both measurements and evaluations of neutron cross sections. Not many cross sections can be obtained absolutely - most cross sections are measured relative to the cross section standards and converted using evaluations of the standards. The previous complete evaluation of the neutron cross section standards was finished in 1987 and disseminated as the NEANDC/INDC and ENDF/B-VI standards. R-matrix model fits for the light elements and non-model least-squares fits for all the cross sections in the evaluation were the basis of the combined fits for all of the data. Some important reactions and constants are not standards, but they assist greatly in the determination of the standard cross sections and reduce their uncertainties - these data were also included in the combined fits. The largest experimental database used in the evaluation was prepared by Poenitz and included about 400 sets of experimental data with covariance matrices of uncertainties that account for all cross-energy, cross-reaction and cross-material correlations. For the evaluation GMA, a least-squares code developed by Poenitz, was used to fit all types of cross sections (absolute and shape), their ratios, spectrum-averaged cross sections and thermal constants in one full analysis. But, the uncertainties derived in this manner, and especially those obtained in the R-matrix model fits, have been judged to be too low and unrealistic. These uncertainties were substantially increased prior to their release in the recommended data files of 1987. Modified percentage uncertainties were reassigned by the United States Cross Section Evaluation Working Group's Standards Subcommittee for a wide range of energies, and no covariance (or correlation) matrices were supplied at that time. The need to re-evaluate the cross section standards is based on the appearance of a significant amount of precise experimental data and improved developments in the methodology of analysis and evaluation. Initial efforts to produce a new evaluation were made by the United States Cross Section Evaluation Working Group which formed a Task Force. It was realized that international cooperation would be needed to produce the evaluation. The Working Party on International Evaluation Cooperation of the Nuclear Energy Agency Nuclear Science Committee formed a Subgroup, and the International Atomic Energy Agency formed a Coordinated Research Project (CRP). These groups worked cooperatively to improve the evaluation process. The major effort in producing the evaluation was through the CRP. The evaluations of the neutron cross section standards were finalized in October 2005. Previous difficulties experienced with a data evaluation problem known as "Peelle's Pertinent Puzzle" create biases in the fit of correlated data, and they have been addressed to reduce this phenomenon. The new evaluations of the cross section standards also include covariance matrices of the uncertainties that contain fully justifiable values. The product of this international effort has been adopted as the neutron standards for ENDF/B-VII.0.

  1. Prevalence and correlation of hypertension among adult population in Bahir Dar city, northwest Ethiopia: a community based cross-sectional study

    PubMed Central

    Anteneh, Zelalem Alamrew; Yalew, Worku Awoke; Abitew, Dereje Birhanu

    2015-01-01

    Background Hypertension is one of the most common causes of premature death and morbidity and has a major impact on health care costs. It is an important public health challenge to both developed and developing countries. The aim of this study was to determine the magnitude and correlates of hypertension. Methods A community-based cross-sectional study was conducted in June 2014 among 681 adult residents of Bahir Dar city using multistage sampling techniques. An interview-administrated questionnaire and physical measurements such as blood pressure (BP), weight, height, and waist and hip circumferences were employed to collect the data. The data were coded, entered, and analyzed with SPSS version 16 software package. Results A total of 678 responses were included in the analysis resulting in a response rate of 99.6%. The findings declared that 17.6%, 19.8%, and 2.2% of respondents were prehypertension, hypertension stage I, and hypertension stage II, respectively, on screening test. The overall prevalence of hypertension (systolic BP ?140 mmHg, or diastolic BP ?90 mmHg, or known hypertensive patient taking medications) was 25.1%. According to the multivariate logistic regression analysis, age; having ever smoked cigarette; number of hours spent walking/cycling per day; number of hours spent watching TV per day; history of diabetes; adding salt to food in addition to the normal amount that is added to the food during cooking; and body mass index were statistically significant predictors of hypertension. Conclusion One out of every four respondents of the study had hypertension, and more than one out of three cases of hypertension (38.8%) did not know that they had the hypertension; 17.6% of the respondents were in prehypertension stage, which adds to overall future risk of hypertension. Therefore, mass screening for hypertension, health education to prevent substance use, regular exercise, reducing salt consumption, and life style modifications are recommended. PMID:26005357

  2. Vocation and avocation: leisure activities correlate with professional engagement, but not burnout, in a cross-sectional survey of UK doctors

    PubMed Central

    2011-01-01

    Background Sir William Osler suggested in 1899 that avocations (leisure activities) in doctors are related to an increased sense of vocation (professional engagement) and a decreased level of burnout. This study evaluated those claims in a large group of doctors practicing in the UK while taking into account a wide range of background variables. Methods A follow-up questionnaire was sent to 4,457 UK-qualified doctors who had been included in four previous studies of medical school selection and training, beginning in 1980, 1985, 1990 and 1989/1991. A total of 2,845 (63.8%) doctors returned the questionnaire. Questions particularly asked about work engagement, satisfaction with medicine as a career, and personal achievement (Vocation/engagement), stress, emotional exhaustion, and depersonalization (BurnedOut), and 29 different leisure activities (Avocation/Leisure), as well as questions on personality, empathy, work experience, and demography. Results Doctors reporting more Avocation/Leisure activities tended to be women, to have older children, to be less surface-rational, more extravert, more open to experience, less agreeable, and to fantasize more. Doctors who were more BurnedOut tended to be men, to be more sleep-deprived, to report a greater workload and less choice and independence in their work, to have higher neuroticism, lower extraversion and lower agreeableness scores, and to have lower self-esteem. In contrast, doctors with a greater sense of Vocation/engagement, tended to see more patients, to have greater choice and independence at work, to have a deep approach to work, to have a more supportive-receptive work environment, to be more extravert and more conscientious, and to report greater self-esteem. Avocation/Leisure activities correlated significantly with Vocation/engagement, even after taking into account 25 background variables describing demography, work, and personality, whereas BurnedOut showed no significant correlation with Avocation/Leisure activities. Popular Culture and High Culture did not differ in their influence on Vocation/engagement, although there was a suggestion that Depersonalization was correlated with more interest in Popular Culture and less interest in High Culture. Conclusion In this cross-sectional study there is evidence, even after taking into account a wide range of individual difference measures, that doctors with greater Avocation/Leisure activities also have a greater sense of Vocation/Engagement. In contrast, being BurnedOut did not relate to Avocation/Leisure activities (but did relate to many other measures). Osler was probably correct in recommending to doctors that, 'While medicine is to be your vocation, or calling, see to it that you also have an avocation'. PMID:21878123

  3. Knee Confidence as It Relates to Self-reported and Objective Correlates of Knee Osteoarthritis: A Cross-sectional Study of 220 Patients.

    PubMed

    Skou, Søren T; Rasmussen, Sten; Simonsen, Ole; Roos, Ewa M

    2015-10-01

    Study Design Cross-sectional study. Objective The objective was to validate, if possible, previously reported associations and to investigate other potential associations between knee confidence and various self-reported and objective measures in an independent cohort of patients with knee osteoarthritis (OA). Background Lack of knee confidence is a frequent symptom in patients with knee OA, but little is known of associations between knee confidence and other common correlates of knee OA. Methods Baseline data from 220 patients with knee OA were applied in ordinal regression analyses, with knee confidence, assessed using item Q3 of the Knee injury and Osteoarthritis Outcome Score, as the dependent variable and self-reported (pain on walking, general health, fear of movement, self-efficacy, function, and previous serious injury) and objective measures (muscle strength, 20-m walk time, and radiographic severity of tibiofemoral OA) as predictor variables. Results Most (95%) of the participants reported lack of knee confidence, and 54% experienced severe or extreme lack of knee confidence. Fear of movement (odds ratio [OR] = 2.06; 95% confidence interval [CI]: 1.15, 3.68), pain on walking (OR = 1.21; 95% CI: 1.09, 1.34), and general health (OR = 0.024; 95% CI: 0.002, 0.259) explained 19% of the variance in knee confidence (P<.001). Conclusion Severe lack of knee confidence is a common finding in individuals with knee OA. Pain on walking was confirmed as a correlate of knee confidence, whereas muscle strength was not. Fear of movement and poor general health were new variables associated with lack of knee confidence. The noncorrelations or poor correlations with other tested variables suggest that a lack of knee confidence may represent an independent treatment target in knee OA of importance to improve mobility. Trials registered at ClinicalTrials.gov (NCT01410409 and NCT01535001). J Orthop Sports Phys Ther 2015;45(10):765-771. Epub 24 Aug 2015. doi:10.2519/jospt.2015.5864. PMID:26304646

  4. Multilevel Correlates of Non-Adherence in Kidney Transplant Patients Benefitting from Full Cost Coverage for Immunosuppressives: A Cross-Sectional Study

    PubMed Central

    Marsicano, Elisa Oliveira; Fernandes, Neimar Silva; Colugnati, Fernando Antônio Basile; Fernandes, Natalia Maria Silva; De Geest, Sabina; Sanders-Pinheiro, Helady

    2015-01-01

    Background Adherence is the result of the interaction of the macro, meso, micro, and patient level factors. The macro level includes full coverage of immunosuppressive medications as is the case in Brazil. We studied the correlates of immunosuppressive non-adherence in post kidney transplant patients in the Brazilian health care system. Methods Using a cross-sectional design, adherence to immunosuppressives was assessed in a sample of 100 kidney transplant patients using a composite non-adherence score consisting of three methods (self-report [i.e., The Basel Adherence Scale for Assessment of Immunossupressives–BAASIS], collateral report, and immunosuppressive blood levels). Multilevel correlations of non-adherence were assessed (macro, meso, micro and patient level). Univariate and multivariate logistic regression was applied to assess the correlates of non-adherence. Results Our sample consisted primarily of male (65%), Caucasians (72%) with a mean age of 45.0 ± 13.5 years old, who received grafts from a living donor (89%), with a mean time after transplantation of 72.3 ± 44.4 months. Prevalence of non-adherence was 51%. Family income higher than five reference wages (21.6 vs. 4%; OR 6.46 [1.35–30.89], p = 0.009; patient level), and having access to private health insurance (35.3% vs. 18.4%; OR 2.42 [0.96–6.10], p = 0.04; meso level) were associated with non-adherence in univariate analysis. Only the higher family income variable was retained in the multiple logistic regression model (OR 5.0; IC: 1.01–25.14; p = 0.04). Conclusions Higher family income was the only factor that was associated with immunosuppressive non-adherence. In Brazil, lower income recipients benefit from better access to care and coverage of health care costs after transplantation. This is supposed to result in a better immunosuppressive adherence compared to high-income patients who have experienced these benefits continuously. PMID:26619070

  5. Radar cross section of insects

    NASA Astrophysics Data System (ADS)

    Riley, J. R.

    1985-02-01

    X-band measurements of radar cross section as a function of the angle between insect body axis and the plane of polarization are presented. A finding of particular interest is that in larger insects, maximum cross section occurs when the E-vector is perpendicular to the body axis. A new range of measurements on small insects (aphids, and planthoppers) is also described, and a comprehensive summary of insect cross-section data at X-band is given.

  6. Cross-sectional assessment of prevalence and correlates of blood-borne and sexually-transmitted infections among Afghan National Army recruits

    PubMed Central

    2012-01-01

    Background Few data are available in Afghanistan to shape national military force health practices, particularly with regard to sexually-transmitted infections (STIs). We measured prevalence and correlates of HIV, syphilis, herpes simplex 2 virus (HSV-2), and hepatitis C virus (HCV) among Afghan National Army (ANA) recruits. Methods A cross-sectional sample of male ANA recruits aged 18–35 years were randomly selected at the Kabul Military Training Center between February 2010 and January 2011. Participants completed an interviewer-administered questionnaire and serum-based rapid testing for syphilis and hepatitis C virus antibody on-site; HIV and HSV-2 screening, and confirmatory testing were performed off-site. Prevalence of each infection was calculated and logistic regression analysis performed to identify correlates. Results Of 5313 recruits approached, 4750 consented to participation. Participants had a mean age of 21.8 years (SD±3.8), 65.5% had lived outside Afghanistan, and 44.3% had no formal education. Few reported prior marijuana (16.3%), alcohol (5.3%), or opiate (3.4%) use. Of sexually active recruits (58.7%, N?=?2786), 21.3% reported paying women for sex and 21.3% reported sex with males. Prevalence of HIV (0.063%, 95% CI: 0.013- 0.19), syphilis (0.65%, 95% CI: 0.44 – 0.93), and HCV (0.82%, 95% CI: 0.58 – 1.12) were quite low. Prevalence of HSV-2 was 3.03% (95% CI: 2.56 - 3.57), which was independently associated with age (Adjusted Odds Ratio (AOR)?=?1.04, 95% CI: 1.00 - 1.09) and having a television (socioeconomic marker) (AOR?=?1.46, 95% CI: 1.03 – 2.05). Conclusion Though prevalence of HIV, HCV, syphilis, and HSV-2 was low, sexual risk behaviors and intoxicant use were present among a substantial minority, indicating need for prevention programming. Formative work is needed to determine a culturally appropriate approach for prevention programming to reduce STI risk among Afghan National Army troops. PMID:22909128

  7. ARMP-02 documentation: Part 2, Chapter 2: Description of the CELL-2 fast and thermal cross-section libraries: Computer code manual

    SciTech Connect

    Ozer, O.; MacFarlane, R.E.; Williams, M.L.; Cobb, W.R.; Tivel, D.E.

    1987-10-01

    This chapter describes the multigroup fast (GAM) and thermal (THERMOS) cross section libraries generated for use with the ARMP-02 codes CELL-2 and EPRI-PRESS. Two sets of libraries are described. The first set referred to as ''Production libraries'' is basically the same as the GAM/THERMOS libraries distributed as part of the original ARMP release for use with the EPRI-CELL code, thus the appropriate documentation from the ARMP computer code manual (EPRI-CCM 3) is reproduced here. The second set of libraries is derived from the national standard data file: ENDF/B-V. The differences between this data and earlier versions of ENDF/B are summarized. This chapter also provides information on the energy group structures used by both sets of libraries, the prompt fission neutron spectra for uranium-235 and plutonium-239, the delayed neutron fractions (yields and decay constants) and the composition of mixed materials. 10 refs., 8 tabs.

  8. The total charm cross section

    SciTech Connect

    Vogt, R

    2007-09-14

    We assess the theoretical uncertainties on the total charm cross section. We discuss the importance of the quark mass, the scale choice and the parton densities on the estimate of the uncertainty. We conclude that the uncertainty on the total charm cross section is difficult to quantify.

  9. XCOM: Photon Cross Sections Database

    National Institute of Standards and Technology Data Gateway

    SRD 8 XCOM: Photon Cross Sections Database (Web, free access)   A web database is provided which can be used to calculate photon cross sections for scattering, photoelectric absorption and pair production, as well as total attenuation coefficients, for any element, compound or mixture (Z <= 100) at energies from 1 keV to 100 GeV.

  10. Dietary correlates of an at-risk BMI among Inuit adults in the Canadian high arctic: cross-sectional international polar year Inuit health survey, 2007-2008

    PubMed Central

    2012-01-01

    Background The study’s objective was to investigate the dietary correlates of an at-risk body mass index (BMI) among Inuit adults from thirty-six communities across the Canadian Arctic using data from the cross-sectional International Polar Year Inuit Health Survey, conducted in 2007–2008. Methods The survey included assessments of 24-hr dietary recall, sociodemographics, physical activity, and anthropometry. Dietary characteristics of overweight and obesity were similar and therefore combined into one at- risk BMI category (?25?kg/m2) for analyses. The relationship between an at-risk BMI and energy intake from macronutrients, high sugar drinks, high-fat foods, saturated fatty acids, and traditional foods were examined entering each dietary variable separately into a logistic regression model as an independent variable. Analyses were adjusted for age, sex, region, kcalories, walking, smoking and alcohol consumption. Further multivariable models considered selected dietary variables together in one model. Results An at-risk BMI was present for 64% with a prevalence of overweight and obesity of 28% and 36%, respectively. Consumption of high-sugar drinks (>15.5% E) was significantly related with having an at-risk BMI (OR?=?1.6; 95% CI 1.2; 2.2), whereas the % E from total carbohydrate evaluated as a continuous variable and as quartiles was inversely related to an at-risk BMI (P?-trend

  11. Classical description of H(1 s ) and H*(n =2 ) for cross-section calculations relevant to charge-exchange diagnostics

    NASA Astrophysics Data System (ADS)

    Cariatore, N. D.; Otranto, S.; Olson, R. E.

    2015-04-01

    In this work, we introduce a classical trajectory Monte Carlo (CTMC) methodology, specially conceived to provide a more accurate representation of charge-exchange processes between highly charged ions and H (1 s ) and H*(n=2 ) . These processes are of particular relevance in power fusion reactor programs, for which charge-exchange spectroscopy has become a useful plasma diagnostics tool. To test the methodology, electron-capture reactions from these targets by 6C ,7+N, and 8+O are studied at impact energies in the 10 -150 keV/amu range. State-selective cross sections are contrasted with those predicted by the standard microcanonical formulation of the CTMC method, the CTMC method with an energy variation of initial binding energies that produces an improved radial electron density, and the atomic orbital close-coupling method. The present results are found in to be much better agreement with the quantum-mechanical results than the results of former formulations of the CTMC method.

  12. Cross Section of Sagittal Otolith

    USGS Multimedia Gallery

    Cross section of a sagittal otolith from a juvenile Chinook salmon 79 days after emergence. The letters represent: H = hatch, E = emergence, FF = first feed, FW = freshwater residence, TDCK = tidal delta check, and D = tidal delta residence (40x objective)....

  13. $?$ absorption cross sections by nucleons

    E-print Network

    Faisal Akram; Bilal Masud

    2013-09-13

    The cross sections of $\\Upsilon $\\ absorption by nucleons are calculated in meson-baryon exchange model using an effective hadronic Lagrangian. Calculated cross sections are found to peak near threshold followed by an increase which tends to settle at large center of mass energy. Peak values are found in range about 1.8 to 4 mb when cutoff parameter of monopole form factor is varied from 1.2 to 1.8 GeV. The results disagree with pQCD calculations but are consistent with the effective value of the absorption cross section extracted from p-A scattering data in E772 experiment at $\\sqrt{s_{NN}}=39$ GeV. We use this data value to find a best fit of the cutoff parameter which enables us provide definite predictions for the values of $\\Upsilon $ absorption cross sections by nucleons for upcoming p-A scattering experiments at RHIC and LHC energies for zero rapidity $b\\bar{b}$ states. The results could be useful in studying the effect of $\\Upsilon $ absorption by nucleons at its production stage in relativistic heavy-ion collision experiments. We also find that thermal averaged values of total absorption cross sections are small enough to rule out the effect of absorption of $\\Upsilon $ by the comovers in the hadronic matter.

  14. Absolute photoionization cross sections of atomic oxygen

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Pareek, P. N.

    1982-01-01

    The absolute values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.

  15. Clinical Significance of Cerebrovascular Biomarkers and White Matter Tract Integrity in Alzheimer Disease: Clinical correlations With Neurobehavioral Data in Cross-Sectional and After 18 Months Follow-ups.

    PubMed

    Wu, Ming-Kung; Lu, Yan-Ting; Huang, Chi-Wei; Lin, Pin-Hsuan; Chen, Nai-Ching; Lui, Chun-Chung; Chang, Wen-Neng; Lee, Chen-Chang; Chang, Ya-Ting; Chen, Sz-Fan; Chang, Chiung-Chih

    2015-07-01

    Cerebrovascular risk factors and white matter (WM) damage lead to worse cognitive performance in Alzheimer dementia (AD). This study investigated WM microstructure using diffusion tensor imaging in patients with mild to moderate AD and investigated specific fiber tract involvement with respect to predefined cerebrovascular risk factors and neurobehavioral data prediction cross-sectionally and after 18 months. To identify the primary pathoanatomic relationships of risk biomarkers to fiber tract integrity, we predefined 11 major association tracts and calculated tract specific fractional anisotropy (FA) values. Eighty-five patients with AD underwent neurobehavioral assessments including the minimental state examination (MMSE) and 12-item neuropsychiatric inventory twice with a 1.5-year interval to represent major outcome factors. In the cross-sectional data, total cholesterol, low-density lipoprotein, vitamin B12, and homocysteine levels correlated variably with WM FA values. After entering the biomarkers and WM FA into a regression model to predict neurobehavioral outcomes, only fiber tract FA or homocysteine level predicted the MMSE score, and fiber tract FA or age predicted the neuropsychiatric inventory total scores and subdomains of apathy, disinhibition, and aberrant motor behavior. In the follow-up neurobehavioral data, the mean global FA value predicted the MMSE and aberrant motor behavior subdomain, while age predicted the anxiety and elation subdomains. Cerebrovascular risk biomarkers may modify WM microstructural organization, while the association with fiber integrity showed greater clinical significance to the prediction of neurobehavioral outcomes both cross-sectionally and longitudinally. PMID:26181568

  16. Statistical features of the thermal neutron capture cross sections

    E-print Network

    M. S. Hussein; B. V. Carlson; A. K. Kerman

    2015-12-17

    We discuss the existence of huge thermal neutron capture cross sections in several nuclei. The values of the cross sections are several orders of magnitude bigger than expected at these very low energies. We lend support to the idea that this phenomenon is random in nature and is similar to what we have learned from the study of parity violation in the actinide region. The idea of statistical doorways is advanced as a unified concept in the delineation of large numbers in the nuclear world. The average number of maxima per unit mass, $$ in the capture cross section is calculated and related to the underlying cross section correlation function and found to be $ = 3/(\\pi \\sqrt{2}\\gamma_{A})$, where $\\gamma_{A}$ is a characteristic mass correlation width which designates the degree of remnant coherence in the system. We trace this coherence to nucleosynthesis which produced the nuclei whose neutron capture cross sections are considered here.

  17. Anomalously large neutron capture cross sections: a random phenomenon?

    E-print Network

    B. V. Carlson; M. S. Hussein; A. K. Kerman

    2015-06-10

    We discuss the existence of huge thermal neutron capture cross sections in several nuclei. The values of the cross sections are several orders of magnitude bigger than expected at these very low energies. We lend support to the idea that this phenomenon is random in nature and is similar to what we have learned from the study of parity violation in the actinide region. The idea of statistical doorways is advanced as a unified concept in the delineation of large numbers in the nuclear world. The average number of maxima per unit mass, $$ in the capture cross section is calculated and related to the underlying cross section correlation function and found to be $ = \\frac{3}{\\pi \\sqrt{2}\\gamma_{A}}$, where $\\gamma_{A}$ is a characteristic mass correlation width which designates the degree of remnant coherence in the system. We trace this coherence to nucleosynthesis which produced the nuclei whose neutron capture cross sections are considered here.

  18. Comparison of the Five Danish Regions Regarding Demographic Characteristics, Healthcare Utilization, and Medication Use—A Descriptive Cross-Sectional Study

    PubMed Central

    Henriksen, Daniel Pilsgaard; Rasmussen, Lotte; Hansen, Morten Rix; Hallas, Jesper; Pottegård, Anton

    2015-01-01

    Background While Denmark is well known for its plethora of registers. Many studies are conducted on research databases that only cover parts of Denmark, and regional differences could potentially threaten these studies’ external validity. The aim of this study was to assess sociodemographic and health related homogeneity of the five Danish regions. Methods We obtained descriptive data for the five Danish regions, using publicly available data sources: Statbank Denmark, the Danish Ministry of Economic Affairs, and Medstat.dk. These data sources comprise aggregate data from four different nationwide registers: The Danish National Patient Register, The Danish Civil Registration System, The Danish Register of Medicinal Product Statistics, and The Danish National Health Service Register for Primary Care. We compared the Danish regions regarding demographic and socioeconomic characteristics, health care utilization, and use of medication. For each characteristic, one-year prevalence was obtained and analyses were performed for 2013 and 2008 to account for possible change over time. Results In 2013, 5,602,628 persons were living in Denmark. The mean age was 40.7 years in the entire Danish population and ranged between 39.6 to 42.4 years in the five regions (coefficient of variation between regions [CV] = 0.028). The proportion of women in Denmark was 50.4% (CV = 0.009). The proportion of residents with low education level was 28.7% (CV = 0.051). The annual number of GP contacts was 7.1 (range: 6.7–7.4, CV = 0.040), and 114 per 1,000 residents were admitted to the hospital (range: 101–131, CV = 0.107). The annual number of persons redeeming a prescription of any medication was 723 per 1,000 residents (range: 718–743, CV = 0.016). Analyses for 2008 showed comparable levels of homogeneity as for 2013. Conclusions We found substantial homogeneity between all of the five Danish regions with regard to sociodemographic and health related characteristics. Epidemiologic studies conducted on regional subsets of Danish citizens have a high degree of generalizability. PMID:26439627

  19. Canonical Correlation: Terms and Descriptions.

    ERIC Educational Resources Information Center

    Pugh, Richard C.; Hu, Yuehluen

    The use of terms to describe and interpret results from canonical correlation analysis has been inconsistent across research studies. This study assembled the terminology related to the use and interpretation of canonical correlation analysis from research articles, textbooks, and computer manuals. Research articles using canonical correlation

  20. Deeply virtual Compton Scattering cross section measured with CLAS

    SciTech Connect

    Guegan, Baptistse

    2014-09-01

    The Generalized Parton Distributions (GPDs) provide a new description of nucleon structure in terms of its elementary constituents, the quarks and the gluons. Including and extending the information provided by the form factors and the parton distribution functions, they describe the correlation between the transverse position and the longitudinal momentum fraction of the partons in the nucleon. Deeply Virtual Compton Scattering (DVCS), the electroproduction of a real photon on a single quark in the nucleon eN --> e'N'g, is the exclusive process most directly interpretable in terms of GPDs. A dedicated experiment to study DVCS with the CLAS detector at Jefferson Lab has been carried out using a 5.9-GeV polarized electron beam and an unpolarized hydrogen target, allowing us to collect DVCS events in the widest kinematic range ever explored in the valence region : 1.0 < Q2 < 4.6 GeV2, 0.1 < xB < 0.58 and 0.09 < -t < 2.0 GeV2. In this paper, we show preliminary results of unpolarized cross sections and of polarized cross section differences for the DVCS channel.

  1. Prevalence, correlates, and prospective predictors of non-suicidal self-injury among New Zealand adolescents: cross-sectional and longitudinal survey data.

    PubMed

    Garisch, Jessica Anne; Wilson, Marc Stewart

    2015-01-01

    Non-suicidal self-injury (NSSI) is common among adolescents and linked to many maladaptive outcomes. This study aimed to assess the prevalence and correlates of NSSI among a community sample of New Zealand adolescents. A self-report questionnaire was administered to adolescents at time 1 (N?=?1162, mean age?=?16.35), and approximately five months later (time 2, N?=?830, mean age?=?16.49). Prevalence and bivariate correlations were assessed at both time points, and cross-lag correlations using matched data (N?=?495, mean age?=?16.23). Lifetime history of NSSI was 48.7 % (females 49.4 %, males 48 %). Consistent with previous international research, NSSI was associated with higher Alexithymia, depression, anxiety, bullying, impulsivity, substance abuse, abuse history and sexuality concerns and lower mindfulness, resilience and self-esteem. Cross-lag correlations suggested NSSI is directly (perhaps causally) related to psychological vulnerability in various domains (e.g., increased depression and lower self-esteem), while bullying may be more distal to NSSI, rather than a proximal predictor. PMID:26157484

  2. Electron-Impact Ionization Cross Section Database

    National Institute of Standards and Technology Data Gateway

    SRD 107 Electron-Impact Ionization Cross Section Database (Web, free access)   This is a database primarily of total ionization cross sections of molecules by electron impact. The database also includes cross sections for a small number of atoms and energy distributions of ejected electrons for H, He, and H2. The cross sections were calculated using the Binary-Encounter-Bethe (BEB) model, which combines the Mott cross section with the high-incident energy behavior of the Bethe cross section. Selected experimental data are included.

  3. Personal, social, and environmental correlates of physical activity in adults living in rural south-west England: a cross-sectional analysis

    PubMed Central

    2013-01-01

    Background Despite the health risks, physical inactivity is common. Identifying the correlates of physical activity to inform the design of interventions to reduce the disease burden associated with physical inactivity is a public health imperative. Rural adults have a unique set of characteristics influencing their activity behaviour, and are typically understudied, especially in England. The aim of this study was to identify the personal, social, and environmental correlates of physical activity in adults living in rural villages. Methods The study used baseline data from 2415 adults (response rate: 37.7%) participating in the first time period of a stepped-wedge cluster randomised trial, conducted in 128 rural villages from south-west England. Data collected included demographic characteristics, social factors, perception of the local environment, village level factors (percentage male, mean age, population density, Index of Multiple Deprivation, and sport market segmentation), and physical activity behaviour. Random effects (“multilevel”) logistic regression models were fitted to the binary outcome whether individuals met physical activity guidelines, and random effects linear regression models were fitted to the continuous outcome MET-minutes per week leisure time physical activity, using the personal, social, environmental, and village-level factors as predictors. Results The following factors both increased the odds of meeting the recommended activity guidelines and were associated with more leisure-time physical activity: being male (p?=?0.002), in good health (p?correlates of physical activity behaviour by focusing on a population exposed to unique environmental conditions. It highlights potentially important correlates of physical activity that could be the focus of interventions targeting rural populations, and demonstrates the need to examine rural adults separately from their urban counterparts. PMID:24261335

  4. Prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK Time Use Survey. Cross-sectional analysis.

    PubMed

    Adams, Jean; White, Martin

    2015-09-01

    This study aimed to document the prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK Time-Use Survey. Respondents reported their main activities, in 10 minute slots, throughout one 24 hour period. Activities were coded into 30 pre-defined codes, including 'cooking, washing up'. Four measures of time spent cooking were calculated: any time spent cooking, 30 continuous minutes spent cooking, total time spent cooking, and longest continuous time spent cooking. Socio-demographic correlates were: age, employment, social class, education, and number of adults and children in the household. Analyses were stratified by gender. Data from 4214 participants were included. 85% of women and 60% of men spent any time cooking; 60% of women and 33% of men spent 30 continuous minutes cooking. Amongst women, older age, not being in employment, lower social class, greater education, and living with other adults or children were positively associated with time cooking. Few differences in time spent cooking were seen in men. Socio-economic differences in time spent cooking may have been overstated as a determinant of socio-economic differences in diet, overweight and obesity. Gender was a stronger determinant of time spent cooking than other socio-demographic variables. PMID:26004671

  5. Prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK Time Use Survey. Cross-sectional analysis?

    PubMed Central

    Adams, Jean; White, Martin

    2015-01-01

    This study aimed to document the prevalence and socio-demographic correlates of time spent cooking by adults in the 2005 UK Time-Use Survey. Respondents reported their main activities, in 10 minute slots, throughout one 24 hour period. Activities were coded into 30 pre-defined codes, including ‘cooking, washing up’. Four measures of time spent cooking were calculated: any time spent cooking, 30 continuous minutes spent cooking, total time spent cooking, and longest continuous time spent cooking. Socio-demographic correlates were: age, employment, social class, education, and number of adults and children in the household. Analyses were stratified by gender. Data from 4214 participants were included. 85% of women and 60% of men spent any time cooking; 60% of women and 33% of men spent 30 continuous minutes cooking. Amongst women, older age, not being in employment, lower social class, greater education, and living with other adults or children were positively associated with time cooking. Few differences in time spent cooking were seen in men. Socio-economic differences in time spent cooking may have been overstated as a determinant of socio-economic differences in diet, overweight and obesity. Gender was a stronger determinant of time spent cooking than other socio-demographic variables. PMID:26004671

  6. Cross sections for electron scattering by atomic potassium

    SciTech Connect

    Msezane, A.Z.; Awuah, P.; Hiamang, S. Center for Theoretical Studies of Physical Systems, Clark Atlanta University, Atlanta, Georgia 30314 ); Allotey, F.K.A. )

    1992-12-01

    Electron elastic and collisional excitation cross sections from the ground state of potassium are calculated using the noniterative integral-equation method of Henry, Rountree, and Smith (Comput. Phys. Commun. 23, 233 (1981)) in the electron energy range 4{le}{ital E}{le}200 eV. Configuration-interaction target wave functions that take account of correlation and polarization effects are used to represent the ground state and the six lowest excited states 4{ital p} {sup 2}{ital P}{degree}, 5{ital s} {sup 2}{ital S}, 3{ital d} {sup 2}{ital D}, 5{ital p} {sup 2}{ital P}{degree}, 4{ital d} {sup 2}{ital D}, and 6{ital s} {sup 2}{ital S}. Elastic and discrete excitation cross sections are obtained in a seven-state close-coupling (7CC) approximation. The 7CC elastic and excitation cross sections are compared and contrasted. Near threshold the elastic cross section dominates the resonance, 4{ital s} {sup 2}{ital S}{r arrow}4{ital p} {sup 2}{ital P}{degree}, and the sum of the other remaining excitation cross sections. Comparison of our total cross sections with some available experimental and theoretical data is also effected. The discrepancy between the recent measurement of the total cross section by Kwan {ital et} {ital al}. (Phys. Rev. A 44, 1620 (1991)) on the one hand and other measurements near threshold on the other hand is explained.

  7. Terahertz radar cross section measurements.

    PubMed

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

    2010-12-01

    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 radar on full-size objects. The measurements are performed in a terahertz time-domain system with freely propagating terahertz pulses generated by tilted pulse front excitation of lithium niobate crystals and measured with sub-picosecond time resolution. The application of a time domain system provides ranging 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. PMID:21164990

  8. A cross-sectional examination of socio-demographic and school-level correlates of children’s school travel mode in Ottawa, Canada

    PubMed Central

    2014-01-01

    Background Active school transport (AST) is an important source of children’s daily physical activity (PA). However, decreasing rates of AST have been reported in multiple countries during the last decades. The purpose of the present study was to examine the socio-demographic and school-level correlates of AST. Methods A stratified sample of children (N?=?567, mean age?=?10.0 years; 57.8% female) was recruited in the Ottawa area. Four sources of data were used for analyses: 1) child questionnaire including questions on school travel mode and time; 2) parent questionnaire providing information on household socio-demographic characteristics; 3) school administrator survey assessing school policies and practices pertaining to PA; and 4) school site audit performed by the study team. Generalized linear mixed models were used to identify socio-demographic and school-level correlates of AST while controlling for school clustering. Results Individual factors associated with higher odds of AST were male gender (OR?=?1.99; 95% CI?=?1.30-3.03), journey time <5 minutes vs. >15 minutes (OR?=?2.26; 95% CI?=?1.17-4.37), and 5–15 minutes vs. >15 minutes (OR?=?2.27; 95% CI?=?1.27-4.03). Children were more likely to engage in AST if school administrators reported that crossing guards were employed (OR?=?2.29; 95% CI?=?1.22-4.30), or if they expressed major or moderate concerns about crime in the school neighbourhood (OR?=?3.34; 95% CI?=?1.34-8.32). In schools that identified safe routes to school and where traffic calming measures were observed, children were much more likely to engage in AST compared to schools without these features (OR?=?7.87; 95% CI?=?2.85-21.76). Moreover, if only one of these features was present, this was not associated with an increased likelihood of AST. Conclusion These findings suggest that providing crossing guards may facilitate AST. Additionally, there was a synergy between the identification of safe routes to school and the presence of traffic calming measures, suggesting that these strategies should be used in combination. PMID:24886211

  9. HIV-related risk behaviours and the correlates among rickshaw pullers of Kamrangirchar, Dhaka, Bangladesh: a cross-sectional study using probability sampling

    PubMed Central

    Hoque, Md Hafiz Ehsanul; Ono-Kihara, Masako; Zamani, Saman; Ravari, Shahrzad Mortazavi; Kihara, Masahiro

    2009-01-01

    Background National HIV serological and behavioural surveillance of Bangladesh repeatedly demonstrated a very high proportion of rickshaw pullers in Dhaka city, having sex with female sex workers (FSWs) and using illicit substances. However, no study has been conducted to identify the correlates of having sex with FSWs among this population. This study aimed to describe behavioural profile of rickshaw pullers in Dhaka city using probability samples and to identify the correlates for having sex with FSWs in order to focus HIV prevention intervention. Methods Six hundred rickshaw pullers were randomly selected from rickshaw garages in the Kamrangirchar area, the single largest slum cluster of Dhaka, Bangladesh, during March–April 2008 using the Proportion Probability to Size method. Participants were interviewed, with a response rate of 99.2% (n = 595), using a structured questionnaire and asked about illicit substance use, sexual behaviour and risk perception for HIV and sexually transmitted diseases. Independent predictors of having sex with FSWs were analysed by multivariate analysis. A qualitative study was subsequently conducted with 30 rickshaw pullers to supplement the findings of the initial survey. Results The proportion of survey respondents who had sex with FSWs and those who used illicit substances in the previous 12 months period were 7.9% and 24.9%, respectively, much lower than the results achieved in the 2003–04 behavioural surveillance (72.8% and 89.9%, respectively). Multivariate analysis revealed the characteristics of younger age, being never married, living alone with family remaining in other districts and using illicit substances in the previous 12 months were significantly associated with having sex with FSWs. Conclusion HIV-related risk behaviour of our study population of the rickshaw pullers was lower than what has been suggested by the results of behavioural surveillance. While this discrepancy should be addressed in further studies, our study emphasizes the importance of focused HIV prevention programs for rickshaw pullers as high-risk behaviour is displayed at an unacceptable level and concentrated in identifiable sub-populations. PMID:19284569

  10. Comparison of Correlates of Bone Mineral Density in Individuals Adhering to Lacto-Ovo, Vegan, or Omnivore Diets: A Cross-Sectional Investigation

    PubMed Central

    Knurick, Jessica R.; Johnston, Carol S.; Wherry, Sarah J.; Aguayo, Izayadeth

    2015-01-01

    Vegetarian diets are associated with factors that may not support bone health, such as low body mass and low intakes of protein; yet, these diets are alkaline, a factor that favors bone mineral density (BMD). This study compared the correlates of BMD in young, non-obese adults consuming meat-based (n = 27), lacto-ovo vegetarian (n = 27), or vegan (n = 28) diets for ?1 year. A 24 h diet recall, whole body DXA scan, 24 h urine specimen, and fasting blood sample were collected from participants. BMD did not differ significantly between groups. Protein intake was reduced ~30% in individuals consuming lacto-ovo and vegan diets as compared to those consuming meat-based diets (68 ± 24, 69 ± 29, and 97 ± 47 g/day respectively, p = 0.006); yet dietary protein was only associated with BMD for those following vegan diets. Urinary pH was more alkaline in the lacto-ovo and vegan groups versus omnivores (6.5 ± 0.4, 6.7 ± 0.4, and 6.2 ± 0.4 respectively, p = 0.003); yet urinary pH was associated with BMD in omnivores only. These data suggest that plant-based diets are not detrimental to bone in young adults. Moreover, diet prescriptions for bone health may vary among diet groups: increased fruit and vegetable intake for individuals with high meat intakes and increased plant protein intake for individuals who follow a vegetarian diet plan. PMID:25970147

  11. Comparison of correlates of bone mineral density in individuals adhering to lacto-ovo, vegan, or omnivore diets: a cross-sectional investigation.

    PubMed

    Knurick, Jessica R; Johnston, Carol S; Wherry, Sarah J; Aguayo, Izayadeth

    2015-05-01

    Vegetarian diets are associated with factors that may not support bone health, such as low body mass and low intakes of protein; yet, these diets are alkaline, a factor that favors bone mineral density (BMD). This study compared the correlates of BMD in young, non-obese adults consuming meat-based (n = 27), lacto-ovo vegetarian (n = 27), or vegan (n = 28) diets for ?1 year. A 24 h diet recall, whole body DXA scan, 24 h urine specimen, and fasting blood sample were collected from participants. BMD did not differ significantly between groups. Protein intake was reduced ~30% in individuals consuming lacto-ovo and vegan diets as compared to those consuming meat-based diets (68 ± 24, 69 ± 29, and 97 ± 47 g/day respectively, p = 0.006); yet dietary protein was only associated with BMD for those following vegan diets. Urinary pH was more alkaline in the lacto-ovo and vegan groups versus omnivores (6.5 ± 0.4, 6.7 ± 0.4, and 6.2 ± 0.4 respectively, p = 0.003); yet urinary pH was associated with BMD in omnivores only. These data suggest that plant-based diets are not detrimental to bone in young adults. Moreover, diet prescriptions for bone health may vary among diet groups: increased fruit and vegetable intake for individuals with high meat intakes and increased plant protein intake for individuals who follow a vegetarian diet plan. PMID:25970147

  12. Prevalence and correlates of psychotropic medication use among older adults in Israel: Cross-sectional and longitudinal findings from two cohorts a decade apart

    PubMed Central

    Blumstein, Tzvia; Benyamini, Yael; Chetrit, Angela; Mizrahi, Eliyahu H.; Lerner-Geva, Liat

    2012-01-01

    Objectives To assess: 1) changes in use of psychotropic medications across two cohorts, ten years apart, of community-dwelling elderly and the socio-demographic, physical and mental health correlates of their use; and 2) changes in psychotropic medication use over 3.5 years follow-up. Methods Data were taken from two national surveys of the Israeli Jewish population aged 75–94, which respectively sampled two cohorts in 1989 (n=1200) and again in 1999 (n=421). Psychotropic medications were assessed from the list of all medications recorded during a face-to-face interview. The current analysis focused on two medication groups: anxiolytics & sedatives/hypnotics and antidepressants. Results Sedatives/hypnotics & anxiolytics use increased from 22.2% in 1989 to 25.4% in 1999 and antidepressants from 3.8% to 4.8% (both nonsignificantly) corresponding to a decline in the health profile of community-dwelling older adults. Similar patterns of associations were observed for socio-demographics, physical and mental health status indicators with use of psychotropic medications across the two cohorts. The pooled multivariate analysis showed significantly higher use of sedative/hypnotics & anxiolytics among women and lower use among religious elderly. Additional risk factors were sleeping problems, number of other medications, depressive symptoms and traumatic life events. Antidepressants use was related to a higher education, ADL disability and depressive symptoms. Longitudinally, use of psychotropic medications was not significantly different among participants who were followed again after 3.5 years. Conclusions Sedative/hypnotics & anxiolytics use was relatively high while antidepressants use was low even among depressed elderly suggesting that some depressed elderly were treated inappropriately with benzodiazepines. PMID:22313035

  13. Clinical, Functional and Health-Related Quality of Life Correlates of Clinically Significant Symptoms of Anxiety and Depression in Patients with Systemic Sclerosis: A Cross-Sectional Survey

    PubMed Central

    Nguyen, Christelle; Ranque, Brigitte; Baubet, Thierry; Bérezné, Alice; Mestre-Stanislas, Caroline; Rannou, François; Papelard, Agathe; Morell-Dubois, Sandrine; Revel, Michel; Moro, Marie-Rose; Guillevin, Loïc; Poiraudeau, Serge; Mouthon, Luc

    2014-01-01

    Objectives To identify clinical, functional and health-related quality of life (HRQoL) correlates of clinically significant symptoms of anxiety and depression in patients with systemic sclerosis (SSc). Methods Three-hundred-and-eighty-one patients fulfilling the American College of Rheumatology and/or the Leroy and Medsger criteria for SSc were assessed for visceral involvement, disability and HRQoL (assessed by SF-36). Clinically significant symptoms of anxiety and depression were evaluated with the Hospital Anxiety Depression Scale (HAD) (defined cut-off?8). Results 9.2% the patients had limited SSc, 50.5% limited cutaneous SSc (lcSSc), and 40.3% diffuse cutaneous SSc (dcSSc). Overall, 40.4% and 58.8% of the patients had clinically significant symptoms of depression and anxiety, respectively. Compared to patients without clinically significant symptoms of depression, patients with clinically significant symptoms of depression had poorer health status, HRQoL mental and physical component, and greater global disability, hand disability and aesthetic impairment. Compared to patients without clinically significant symptoms of anxiety, patients with clinically significant symptoms of anxiety had poorer SF-36 mental and physical component scores. On multivariable analysis, excluding mental component score of SF-36, variables independently associated with clinically significant symptoms of depression and anxiety were global disability and physical component of SF-36, plus female gender for clinically significant symptoms of anxiety only. Remarkably, patients with and without clinically significant psychiatric symptoms were comparable for all disease-related clinical features assessed. Conclusion High levels of clinically significant symptoms of anxiety and depression are observed among SSc patients. Clinically significant psychiatric symptoms are rather associated with increased disability and altered HRQoL, than with disease-specific organ manifestations. PMID:24587375

  14. Physical activity level and its sociodemographic correlates in a peri-urban Nepalese population: a cross-sectional study from the Jhaukhel-Duwakot health demographic surveillance site

    PubMed Central

    2014-01-01

    Background Physical inactivity is a leading risk factor for cardiovascular and other noncommunicable diseases in high-, low- and middle-income countries. Nepal, a low-income country in South Asia, is undergoing an epidemiological transition. Although the reported national prevalence of physical inactivity is relatively low, studies in urban and peri-urban localities have always shown higher prevalence. Therefore, this study aimed to measure physical activity in three domains—work, travel and leisure—in a peri-urban community and assess its variations across different sociodemographic correlates. Methods Adult participants (n?=?640) from six randomly selected wards of the Jhaukhel-Duwakot Health Demographic Surveillance Site (JD-HDSS) near Kathmandu responded to the Global Physical Activity Questionnaire. To determine total physical activity, we calculated the metabolic equivalent of task in minutes/week for each domain and combined the results. Respondents were categorized into high, moderate or low physical activity. We also calculated the odds ratio for low physical activity in various sociodemographic variables and self-reported cardiometabolic states. Results The urbanizing JD-HDSS community showed a high prevalence of low physical activity (43.3%; 95% CI 39.4–47.1). Work-related activity contributed most to total physical activity. Furthermore, women and housewives and older, more educated and self-or government-employed respondents showed a greater prevalence of physical inactivity. Respondents with hypertension, diabetes or overweight/obesity reported less physical activity than individuals without those conditions. Only 5% of respondents identified physical inactivity as a cardiovascular risk factor. Conclusions Our findings reveal a high burden of physical inactivity in a peri-urban community of Nepal. Improving the level of physical activity involves sensitizing people to its importance through appropriate multi-sector strategies that provide encouragement across all sociodemographic groups. PMID:24628997

  15. A new technique for dosimetry reaction cross-section evaluation

    SciTech Connect

    Badikov, S.A.

    2011-07-01

    Document available in abstract form only, full text of document follows: An objective of this paper is a unification of the procedure for dosimetry reaction cross-section evaluation. A set of requirements for the unified evaluation procedure is presented. A new code (ORTHO) was developed in order to meet these requirements. A statistical model, an algorithm, and the basic formulae employed in the code are described. The code was used for Ti48(n,p) reaction cross-section evaluation. The results of the evaluation are compared to International Reactor Dosimetry File (IRDF)-2002 data. The evaluated cross-sections and their correlations from this work are in good agreement with the IRDF-2002 evaluated data, whereas the uncertainties of the evaluated cross-sections are inconsistent. (authors)

  16. Recent fission cross section standards measurements

    SciTech Connect

    Wasson, O.A.

    1985-01-01

    The /sup 235/U(n,f) reaction is the standard by which most neutron induced fission cross sections are determined. Most of these cross sections are derived from relatively easy ratio measurements to /sup 235/U. However, the more difficult /sup 235/U(n,f) cross section measurements require the use of advanced neutron detectors for the determination of the incident neutron fluence. Examples of recent standard cross section measurements are discussed, various neutron detectors are described, and the status of the /sup 235/U(n,f) cross section standard is assessed. 23 refs., 8 figs., 4 tabs.

  17. SNL RML recommended dosimetry cross section compendium

    SciTech Connect

    Griffin, P.J.; Kelly, J.G.; Luera, T.F.; VanDenburg, J.

    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.

  18. Doubly differential and integral cross sections for electron elastic scattering by hydrogen sulfide

    NASA Astrophysics Data System (ADS)

    Aouchiche, H.; Medegga, F.; Champion, C.

    2014-08-01

    Theoretical doubly differential and integral cross sections for elastic scattering of electrons by hydrogen sulfide vapor are here reported for impact energies ranging from 10 eV to 10 keV. The calculations are carried out within the partial-wave formalism by means of a spherical complex optical potential model taking into account a static contribution deduced from a single-center Hartree-Fock target description as well as correlation-polarization and exchange effects. The results clearly point out the role played by the exchange and the correlation-polarization in particular at low incident energies and around the observed minima. Both doubly differential and integral cross sections are finally compared with a large set of experimental data and a satisfactory agreement is observed.

  19. Rheologic results and their correlation to hemostatic changes in patients with moderate and severe preeclampsia: an observational cross-sectional study.

    PubMed

    Soliman, Amr A; Csorba, Roland; Yilmaz, Asli; Tsikoaras, Panagioti; von Tempelhoff, Georg-Friedrich

    2015-01-01

    Previous study have shown an association between failure of physiological hemodilution during 2nd trimester and an increased risk for the development of subsequent pregnancy complications such as early birth, birth of a growth retarded newborn (IUGR), low fetal birth weight and preeclampsia. The latter complication in particular goes along with dramatic changes in the placental perfusion as well as systemic maternal blood flow. Severity of preeclampsia may be preceded by distinct impaired hemodilution and reflected by the results of rheological parameters. A subgroup analysis was performed in a community based retrospective study of 4,985 consecutively recorded singleton pregnant women of whom 423 had preeclampsia. Mean 2nd trimester hemoglobin levels and blood rheological results at the time of delivery were assessed and compared in women with moderate and severe preeclampsia. Mean 2nd trimester hemoglobin levels were calculated from the maternal records. Rheological variables included plasma viscosity (KSPV 1 Fresenius) and Red blood cell aggregation in stasis and under low shear conditions (MA1-Aggregometer; Myrenne). According to the definition of the German Society of Gynecology and Obstetrics (DGGG) 314 women had moderate preeclampsia (74.2%), while 109 had severe preeclampsia due to the presence of a blood pressure>170/110 mmHg (n=41; 9.7%), and/or IUGR<5th percentile (n=28; 6.6%), and/or HELLP-Syndrome (n=10; 2.4%), and/or proteinuria?5 g/24 h (n=30; 7.1%). Age, BMI, smoking, and maternal weight were comparable in the groups, while gestational age at delivery as well as fetal outcome parameter were statistically significant unfavourable in patients with severe preeclampsia. Mean 2nd trimester hemoglobin level were statistically significantly higher in women who developed severe vs. moderate preeclampsia (m=12.75±0.99 g/dL vs. m=12.50±1.05 g/dL; p=0.033). However, in the ROC calculations a hemoglobin value of 12.05 g/dL revealed best sensitivity (78%) and specificity (33.8%) in women with subsequent diagnosis of severe preeclampsia, whereas sensitivity was 100% for a value>10.95 g/dL. There were no statistically significant differences for none of the rheological parameters at the time of delivery between groups of patient with moderate v.s severe preeclampsia. Severe preeclampsia and IUGR, however, was associated with statistically significantly higher RBC aggregation as compared to patients with moderate preeclampsia. Plasma viscosity was statistically significantly (p<0.05) correlated with Fibrinogen values (r=0.16), leukocyte-(r=0.11) and platelets-count (r=0.127), and hemoglobin/hematocrit values in particular (r=0.23/0.26). Although mean 2nd trimester hemoglobin concentration are higher in patients with subsequent development of severe preeclampsia, due to the low sensitivity and specificity of this parameter clinical use for identifying women at risk is of limited value. On the other hand, a hemoglobin value below 11.0 g/dL excluded the risk for severe preeclampsia to 100%. Blood rheological parameters at the time of delivery in the absence of IUGR are not markedly influenced by severity of preeclampsia. PMID:23089882

  20. Prevalence, correlates and clinical usefulness of antibodies to RNA polymerase III in systemic sclerosis: a cross-sectional analysis of data from an Australian cohort

    PubMed Central

    2011-01-01

    Introduction The prevalence of antibodies to RNA polymerase III (anti-RNAP) differs among systemic sclerosis (SSc) cohorts worldwide. Previously reported associations of anti-RNAP include diffuse cutaneous disease, tendon friction rubs and renal crisis, with recent reports suggesting a close temporal association between malignancy and SSc disease onset among patients with anti-RNAP. Methods Patients with SSc were tested for the presence of anti-RNAP at recruitment into the Australian Scleroderma Cohort Study. We used univariate and multivariable methods to identify and quantify clinical and laboratory correlates of anti-RNAP in SSc. Diagnostic testing procedures were used to determine the usefulness of these antibodies in estimating the likelihood of clinically important outcomes. Results There were 451 patients with mean ± standard deviation age and disease duration at recruitment of 58.1 ± 12.4 and 11.6 ± 10.0 years, respectively; 151 (33.5%) patients were recruited within 5 years of diagnosis of SSc. Overall, 69 (15.3%) patients had anti-RNAP. Univariate associations of anti-RNAP were diffuse disease (75.4% vs. 20.9%, P < 0.0001), joint contractures (73.9% vs. 30.1%, P < 0.0001), greater highest-recorded modified Rodnan skin score (20.6 ± 12.4 vs. 10.1 ± 7.9, P < 0.0001), synovitis (31.9% vs. 19.9%, P = 0.03), myositis (2.9% vs. 0.5%, P = 0.05), systemic hypertension (59.4% vs. 39.7%, P = 0.002), renal crisis (24.6% vs. 1.8%, P < 0.0001) and malignancy diagnosed within 5 years of onset of SSc skin disease (13.3% vs. 3.9%, P = 0.01). In multiple regression analysis, after adjustment for other covariates, anti-RNAP were independently associated with renal crisis (odds ratio (OR) 3.8, 95% confidence interval (CI) 1.2 to 11.5, P = 0.02; positive predictive value (PPV) 24.6%, negative predictive value (NPV) 98.2%), diffuse disease (OR 6.4, 95% CI 2.9 to 13.8, P < 0.0001; PPV 75.4%, NPV 20.9%), joint contractures (OR 2.5, 95% CI 1.2 to 5.3, P = 0.02; PPV 73.9%, NPV 69.9%) and malignancy diagnosed within 5 years of onset of SSc skin disease (OR 4.2, 95% CI 1.3 to 13.4, P = 0.01; PPV 13.3%, NPV 96.1%). Conclusions Anti-RNAP status is a clinically useful prognostic marker in SSc and enables clinicians to identify patients at high risk of developing renal crisis, synovitis, myositis and joint contractures. Patients with anti-RNAP also have an increased risk of malignancy within a 5-year timeframe before or after onset of SSc skin changes. PMID:22189167

  1. [Fast neutron cross section measurements

    SciTech Connect

    Knoll, G.F.

    1992-10-26

    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.

  2. Changes in Cross-Sectional Area and Transverse Diameter of the Heart on Inspiratory and Expiratory Chest CT: Correlation with Changes in Lung Size and Influence on Cardiothoracic Ratio Measurement

    PubMed Central

    Matsuoka, Shin; Matsushita, Shoichiro; Kurihara, Yasuyuki; Nakajima, Yasuo

    2015-01-01

    Objective The aim of this study was to investigate physiological changes in cardiac area and diameters between inspiratory and expiratory chest computed tomography (CT), and to assess their correlation with lung size change and influence on cardiothoracic ratio (CTR) measurements. Materials and Methods The institutional review board of our institution approved this study, and informed consent was waived. Forty-three subjects underwent inspiratory and expiratory chest CT as part of routine clinical care. On both inspiratory and expiratory scans, lung volumes and maximum lung diameters (transverse and vertical directions) were measured. The maximum cardiac cross-sectional area (CSA) and the maximum transverse cardiac diameter were measured on both scans, and the CT-based CTR was calculated. Changes in the lung and cardiac measurements were expressed as the expiratory/inspiratory (E/I) ratios. Comparisons between inspiratory and expiratory measurements were made by the Wilcoxon signed-rank test. Correlations between the E/I ratios of lung and heart measurements were evaluated by Spearman’s rank correlation analysis. Results Cardiac CSA and transverse cardiac diameter was significantly larger on expiratory than on inspiratory CT (p < 0.0001). Significant negative correlations were found between the E/I ratios of these cardiac measurements and the E/I ratios of lung volume and vertical lung diameter (p < 0.01). CT-based CTR was significantly larger on expiration than on inspiration (p < 0.0001). Conclusions Heart size on chest CT depends on the phase of ventilation, and is correlated with changes in lung volume and craniocaudal lung diameter. The CTR is also significantly influenced by ventilation. PMID:26151361

  3. Nuclear Science and Technology, November 2000. NEUTRON CROSS SECTION EVALUATIONS

    E-print Network

    Nuclear Science and Technology, November 2000. 1 NEUTRON CROSS SECTION EVALUATIONS FOR 238 U UP and Power Engineering, 249020 Obninsk, Russia A.Ventura ENEA, Nuclear Data Center and INFN, Bologna Section of the statistical description that includes direct, pre-equilibrium and equilibrium mechanisms of nuclear reactions

  4. Annular-Cross-Section CFE Chamber

    NASA Technical Reports Server (NTRS)

    Sharnez, Rizwan; Sammons, David W.

    1994-01-01

    Proposed continuous-flow-electrophoresis (CFE) chamber of annular cross section offers advantages over conventional CFE chamber, and wedge-cross-section chamber described in "Increasing Sensitivity in Continuous-Flow Electrophoresis" (MFS-26176). In comparison with wedge-shaped chamber, chamber of annular cross section virtually eliminates such wall effects as electro-osmosis and transverse gradients of velocity. Sensitivity enhanced by incorporating gradient maker and radial (collateral) flow.

  5. Cross Sections for Electron Collisions with Methane

    SciTech Connect

    Song, Mi-Young Yoon, Jung-Sik; Cho, Hyuck; Itikawa, Yukikazu; Karwasz, Grzegorz P.; Kokoouline, Viatcheslav; Nakamura, Yoshiharu; Tennyson, Jonathan

    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.

  6. Cross-section fluctuations in open microwave billiards and quantum graphs: The counting-of-maxima method revisited

    NASA Astrophysics Data System (ADS)

    Dietz, B.; Richter, A.; Samajdar, R.

    2015-08-01

    The fluctuations exhibited by the cross sections generated in a compound-nucleus reaction or, more generally, in a quantum-chaotic scattering process, when varying the excitation energy or another external parameter, are characterized by the width ?corr of the cross-section correlation function. Brink and Stephen [Phys. Lett. 5, 77 (1963), 10.1016/S0375-9601(63)80037-7] proposed a method for its determination by simply counting the number of maxima featured by the cross sections as a function of the parameter under consideration. They stated that the product of the average number of maxima per unit energy range and ?corr is constant in the Ercison region of strongly overlapping resonances. We use the analogy between the scattering formalism for compound-nucleus reactions and for microwave resonators to test this method experimentally with unprecedented accuracy using large data sets and propose an analytical description for the regions of isolated and overlapping resonances.

  7. Total cross sections for neutron-nucleus scattering

    E-print Network

    S. V. Suryanarayana; H. Naik; S. Ganesan; S. Kailas; R. K. Choudhury; Guinyum Kim

    2010-05-31

    Systematics of neutron scattering cross sections on various materials for neutron energies up to several hundred MeV are important for ADSS applications. Ramsauer model is well known and widely applied to understand systematics of neutron nucleus total cross sections. In this work, we examined the role of nuclear effective radius parameter (r$_0$) on Ramsauer model fits of neutron total cross sections. We performed Ramsauer model global analysis of the experimental neutron total cross sections reported by W. P. Abfalterer, F. B. Bateman, {\\it et. al.,}, from 20MeV to 550MeV for nuclei ranging from Be to U . The global fit functions which can fit total cross section data over periodic table are provided along with the required global set of parameters. The global fits predict within $\\pm 8%$ deviation to data, showing the scope for improvement. It has been observed that a finer adjustment of r$_0$ parameter alone can give very good Ramsauer model description of neutron total scattering data within $\\pm 4%$ deviation. The required r$_0$ values for Ramsauer model fits are shown as a function of nuclear mass number and an empirical formula is suggested for r$_0$ values as a function of mass number. In optical model approach for neutron scattering, we have modified the real part of Koning-Deleroche potentails to fit the neutron total cross sections using SCAT2 code. The modified potentails have a different energy dependence beyond 200MeV of neutron energy and fit the total cross sections from Al to Pb.

  8. Inadequacy of Scaling Arguments for Neutrino Cross Sections

    E-print Network

    A. C. Hayes

    2003-11-12

    The problem with the use of scaling arguments for simultaneous studies of different weak interaction processes is discussed. When different neutrino scattering cross sections involving quite different momentum transfers are being compared it difficult to define a meaningful single scaling factor to renormalize calculated cross sections. It has been suggested that the use of such scaling can be used to estimate high energy neutrino cross sections from low energy neutrino cross sections. This argument has lead to questions on the consistency of the magnitude of the LSND muon neutrino cross sections on $^{12}$C relative to other lower energy weak processes. The issue is revisited here and from inspection of the structure of the form factors involved it is seen that the problem arises from a poor description of the transition form factors at high momentum transfer. When wave functions that reproduce the transverse magnetic inelastic (e,e') scattering form factor for the 15.11 MeV state in $^{12}$C are used there is no longer a need for scaling the axial current, and the different weak interactions rates involving the T=1 1$^+$ triplet in mass 12 are consistent with one another.

  9. Neutrino flux predictions for cross section measurements

    SciTech Connect

    Hartz, Mark

    2015-05-15

    Experiments that measure neutrino interaction cross sections using accelerator neutrino sources require a prediction of the neutrino flux to extract the interaction cross section from the measured neutrino interaction rate. This article summarizes methods of estimating the neutrino flux using in-situ and ex-situ measurements. The application of these methods by current and recent experiments is discussed.

  10. Absolute partial photoionization cross sections of ozone.

    SciTech Connect

    Berkowitz, J.; Chemistry

    2008-04-01

    Despite the current concerns about ozone, absolute partial photoionization cross sections for this molecule in the vacuum ultraviolet (valence) region have been unavailable. By eclectic re-evaluation of old/new data and plausible assumptions, such cross sections have been assembled to fill this void.

  11. Absolute Differential Positronium-Formation Cross Sections

    NASA Astrophysics Data System (ADS)

    Shipman, M.; Armitage, S.; Beale, J.; Brawley, S. J.; Fayer, S. E.; Garner, A. J.; Leslie, D. E.; Van Reeth, P.; Laricchia, G.

    2015-07-01

    The first absolute experimental determinations of the differential cross sections for the formation of ground-state positronium are presented for He, Ar, H2 , and CO2 near 0°. Results are compared with available theories. The ratio of the differential and integrated cross sections for the targets exposes the higher propensity for forward emission of positronium formed from He and H2 .

  12. Quantitative CT Measurement of Cross-sectional Area of Small

    E-print Network

    measured CSA less than 5 mm2 and 5­10 mm2 , and calculated the percentage of the total CSA for the lungQuantitative CT Measurement of Cross-sectional Area of Small Pulmonary Vessel in COPD: Correlations (FEV1)% predicted (r = 0.29, P capacity (r = 0.45, P

  13. Neutron removal cross section as a measure of neutron skin

    E-print Network

    D. Q. Fang; Y. G. Ma; X. Z. Cai; W. D. Tian; H. W. Wang

    2010-04-20

    We study the relation between neutron removal cross section ($\\sigma_{-N}$) and neutron skin thickness for finite neutron rich nuclei using the statistical abrasion ablation (SAA) model. Different sizes of neutron skin are obtained by adjusting the diffuseness parameter of neutrons in the Fermi distribution. It is demonstrated that there is a good linear correlation between $\\sigma_{-N}$ and the neutron skin thickness for neutron rich nuclei. Further analysis suggests that the relative increase of neutron removal cross section could be used as a quantitative measure for the neutron skin thickness in neutron rich nuclei.

  14. Evaluation of the /sup 238/U neutron total cross section

    SciTech Connect

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

    1982-12-01

    Experimental energy-averaged neutron total cross sections of /sup 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.

  15. Uncertainty quantification in fission cross section measurements at LANSCE

    DOE PAGESBeta

    Tovesson, F.

    2015-01-09

    Neutron-induced fission cross sections have been measured for several isotopes of uranium and plutonium at the Los Alamos Neutron Science Center (LANSCE) over a wide range of incident neutron energies. The total uncertainties in these measurements are in the range 3–5% above 100 keV of incident neutron energy, which results from uncertainties in the target, neutron source, and detector system. The individual sources of uncertainties are assumed to be uncorrelated, however correlation in the cross section across neutron energy bins are considered. The quantification of the uncertainty contributions will be described here.

  16. Motivation Selection CC Cross Sections Summary Charged Current DIS Cross Sections with a

    E-print Network

    Raval, Amita

    Motivation Selection CC Cross Sections Summary Charged Current DIS Cross Sections polarised e+ 21st April 2010 1 / 15 #12;Motivation Selection CC Cross Sections Summary Charged Current Interaction: Motivation Extraction of MW d2(e+p) dxdQ2 = (1 + P) × G2 F M4 W 2(Q2 + M2 W )2 u + c + (1 - y)2

  17. Silicon Detector System for Cross Section Measurements

    NASA Technical Reports Server (NTRS)

    2003-01-01

    In order to estimate the radiation shielding effectiveness of materials it is necessary to know cosmic ray particles are broken up as they pass though these materials. The breakup of cosmic ray particles is characterized by the nuclear fragmentation cross sections, i.e. an effective geometrical cross section assigned to each target nucleus that represents its apparent size for fragmenting the incident particle. The values of these cross sections depend on the details of nuclear physics and cannot be calculated from first principles owing to the many-body nature of the interactions. The only way to determine them is to measure them. Once a sufficient number of cross sections have been measured, the systematic nature of the interactions allows other cross-sections to be estimated. The number of cross sections that contribute to the estimation of shielding effectiveness is very large 10,000. Fortunately most make minor contributions. These can be estimated from nuclear systematics. Only those who's uncertainties make significant contributions to the error in the shielding effectiveness estimations need to be measured. In the past it has proven difficult to measure light fragment production cross sections from the interactions of heavy cosmic rays owing to the size of the detectors used. We have developed a highly pixilated silicon (Si) detector system that can individually identify these light fragments while making efficient use of costly accelerator time. This system is an outgrowth of detector technology developed under a CDDF and a Code S sponsored cosmic ray experiment.

  18. Inclined Bodies of Various Cross Sections at Supersonic Speeds

    NASA Technical Reports Server (NTRS)

    Jorgensen, Leland H.

    1958-01-01

    To aid in assessing effects of cross-sectional shape on body aerodynamics, the forces and moments have been measured for bodies with circular, elliptic, square, and triangular cross sections at Mach numbers 1.98 and 3.88. Results for bodies with noncircular cross sections have been compared with results for bodies of revolution having the same axial distribution of cross-sectional area (and, thus, the same equivalent fineness ratio). Comparisons have been made for bodies of fineness ratios 6 and 10 at angles of attack from 0 deg to about 20 deg and for Reynolds numbers, based on body length, of 4.0 x 10(exp 6) and 6.7 x 10(exp 6). The results of this investigation show that distinct aerodynamic advantages can be obtained by using bodies with noncircular cross sections. At certain angles of bank, bodies with elliptic, square, and triangular cross sections develop considerably greater lift and lift-drag ratios than equivalent bodies of revolution. For bodies with elliptic cross sections, lift and pitching-moment coefficients can be correlated with corresponding coefficients for equivalent circular bodies. It has been found that the ratios of lift and pitching-moment coefficients for an elliptic body to those for an equivalent circular body are practically constant with change in both angle of attack and Mach number. These lift and moment ratios are given very accurately by slender-body theory. As a result of this agreement, the method of NACA Rep. 1048 for computing forces and moments for bodies of revolution has been simply extended to bodies with elliptic cross sections. For the cases considered (elliptic bodies of fineness ratios 6 and 10 having cross-sectional axis ratios of 1.5 and 2), agreement of theory with experiment is very good. As a supplement to the force and moment results, visual studies of the flow over bodies have been made by use of the vapor-screen, sublimation, and white-lead techniques. Photographs from these studies are included in the report.

  19. Nucleon-Nucleon Total Cross Section

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    2008-01-01

    The total proton-proton and neutron-proton cross sections currently used in the transport code HZETRN show significant disagreement with experiment in the GeV and EeV energy ranges. The GeV range is near the region of maximum cosmic ray intensity. It is therefore important to correct these cross sections, so that predictions of space radiation environments will be accurate. Parameterizations of nucleon-nucleon total cross sections are developed which are accurate over the entire energy range of the cosmic ray spectrum.

  20. Neutron Capture Cross Section of 239Pu

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

    The Detector for Advanced Neutron Capture Experiments (DANCE) has been used to measure the 239Pu(n,?) cross section from 10 eV to the keV region. Three experimental run conditions were used to characterize the prompt fission ?-ray spectrum across the entire energy regime, measure the cross section in the resolved resonance region, and obtain necessary count rate well into the keV region. The preliminary cross sections are in good agreement with current evaluations from 10 eV to 80 keV.

  1. Neutron cross section covariances in the resolved resonance region.

    SciTech Connect

    Herman,M.; Mughabghab, S.F.; Oblozinsky, P.; Pigni, M.T.; Rochman, D.

    2008-04-01

    We present a detailed analysis of the impact of resonance parameter uncertainties on covariances for neutron capture and fission cross sections in the resolved resonance region. Our analysis uses the uncertainties available in the recently published Atlas of Neutron Resonances employing the Multi-Level Breit-Wigner formalism. We consider uncertainties on resonance energies along with those on neutron-, radiative-, and fission-widths and examine their impact on cross section uncertainties and correlations. We also study the effect of the resonance parameter correlations deduced from capture and fission kernels and illustrate our approach on several practical examples. We show that uncertainties of neutron-, radiative- and fission-widths are important, while the uncertainties of resonance energies can be effectively neglected. We conclude that the correlations between neutron and radiative (fission) widths should be taken into account. The multi-group cross section uncertainties can be properly generated from both the resonance parameter covariance format MF32 and the cross section covariance format MF33, though the use of MF32 is more straightforward and hence preferable.

  2. A nuclear cross section data handbook

    SciTech Connect

    Fisher, H.O.M.

    1989-12-01

    Isotopic information, reaction data, data availability, heating numbers, and evaluation information are given for 129 neutron cross-section evaluations, which are the source of the default cross sections for the Monte Carlo code MCNP. Additionally, pie diagrams for each nuclide displaying the percent contribution of a given reaction to the total cross section are given at 14 MeV, 1 MeV, and thermal energy. Other information about the evaluations and their availability in continuous-energy, discrete-reaction, and multigroup forms is provided. The evaluations come from ENDF/B-V, ENDL85, and the Los Alamos Applied Nuclear Science Group T-2. Graphs of all neutron and photon production cross-section reactions for these nuclides have been categorized and plotted. 21 refs., 5 tabs.

  3. Status of neutron dosimetry cross sections

    SciTech Connect

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

    1992-12-31

    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.

  4. The radar cross section of dielectric disks

    NASA Technical Reports Server (NTRS)

    Levine, D. M.

    1982-01-01

    A solution is presented for the backscatter (nonstatic) radar cross section of dielectric disks of arbitrary shape, thickness and dielectric constant. The result is obtained by employing a Kirchhoff type approximation to obtain the fields inside the disk. The internal fields induce polarization and conduction currents from which the scattered fields and the radar cross section can be computed. The solution for the radar cross section obtained in this manner is shown to agree with known results in the special cases of normal incidence, thin disks and perfect conductivity. The solution can also be written as a product of the reflection coefficient of an identically oriented slab times the physical optics solution for the backscatter cross section of a perfectly conducting disk of the same shape. This result follows directly from the Kirchhoff type approximation without additional assumptions.

  5. The radar cross section of dielectric disks

    NASA Technical Reports Server (NTRS)

    Le Vine, D. M.

    1984-01-01

    A solution is presented for the backscatter (monostatic) radar cross section of dielectric disks of arbitrary shape, thickness, and dielectric constant. The result is obtained by employing a Kirchhoff-type approximation to obtain the fields inside the disk. The internal fields induce polarization and conduction currents from which the scattered fields and the radar cross section can be computed. The solution for the radar cross section obtained in this manner will be shown to agree with known results in the special cases of normal incidence, thin disks, and perfect conductivity. It will also be shown that the solution can be written as a product of the reflection coefficient of an identically oriented slab times the physical optics solution for the backscatter cross section of a perfectly conducting disk of the same shape. This result follows directly from the Kirchhoff-type approximation without additional assumptions.

  6. Asymptotic cross sections for composite projectile reactions 

    E-print Network

    Neves, Andrea Marolt Pimenta

    1995-01-01

    The First Born Approximation has been used to compute excitation and ionization cross sections for ion-atom collisions involving two electrons at high energies. The projectile is treated semi-classically following a straight ...

  7. MODELING AND FISSION CROSS SECTIONS FOR AMERICIUM.

    SciTech Connect

    ROCHMAN, D.; HERMAN, M.; OBLOZINSKY, P.

    2005-05-01

    This is the final report of the work performed under the LANL contract on the modeling and fission cross section for americium isotopes (May 2004-June 2005). The purpose of the contract was to provide fission cross sections for americium isotopes with the nuclear reaction model code EMPIRE 2.19. The following work was performed: (1) Fission calculations capability suitable for americium was implemented to the EMPIRE-2.19 code. (2) Calculations of neutron-induced fission cross sections for {sup 239}Am to {sup 244g}Am were performed with EMPIRE-2.19 for energies up to 20 MeV. For the neutron-induced reaction of {sup 240}Am, fission cross sections were predicted and uncertainties were assessed. (3) Set of fission barrier heights for each americium isotopes was chosen so that the new calculations fit the experimental data and follow the systematics found in the literature.

  8. Bibliography of photoabsorption cross-section data

    NASA Technical Reports Server (NTRS)

    Hudson, R. D.; Kieffer, L. J.

    1970-01-01

    This bibliography contains only references which report a measured or calculated photoabsorption cross section (relative or normalized) in regions of continuous absorption. The bibliography is current as of January 1, 1970.

  9. Cross section measurements with monoenergetic muon neutrinos

    E-print Network

    Spitz, Joshua B.

    The monoenergetic 236 MeV muon neutrino from charged kaon decay at rest (K[superscript +] ? ?[superscript +]?[subscript ?]) can be used to produce a novel set of cross section measurements. Applicable for short- and ...

  10. Ultraviolet absorption cross sections of hydrogen peroxide

    NASA Technical Reports Server (NTRS)

    Lin, C. L.; Rohatgi, N. K.; Demore, W. B.

    1978-01-01

    Absorption cross-sections of hydrogen peroxide vapor and of neutral aqueous solutions of hydrogen peroxide were measured in the wavelength range from 195 to 350 nm at 296 K. The spectrophotometric procedure is described, and the reported cross-sections are compared with values obtained by other researchers. Photodissociation coefficients of atmospheric H2O2 were calculated for direct absorption of unscattered solar radiation, and the vertical distributions of these coefficients are shown for various solar zenith angles.

  11. Differential Cross Sections for Electromagnetic Dissociation

    E-print Network

    John W. Norbury; Anne Adamczyk

    2006-12-19

    Differential cross sections for electromagnetic dissociation in nucleus-nucleus collisions are calculated. The kinetic energy distribution is parameterized with a Boltzmann distribution and the angular distribution is assumed isotropic in the projectile frame. In order to be useful for three-dimensional transport codes, these cross sections are available in both the projectile and lab frames. Comparison between theory and experiment is good. The formalism applies to single and multiple nucleon removal, alpha particle removal, and fission in electromagnetic reactions of nuclei.

  12. Path forward for dosimetry cross sections

    SciTech Connect

    Griffin, P.J.; Peters, C.D.

    2011-07-01

    In the 1980's the dosimetry community embraced the need for a high fidelity quantification of uncertainty in nuclear data used for dosimetry applications. This led to the adoption of energy-dependent covariance matrices as the accepted manner of quantifying the uncertainty data. The trend for the dosimetry community to require high fidelity treatment of uncertainty estimates has continued to the current time where requirements on nuclear data are codified in standards such as ASTM E 1018. This paper surveys the current state of the dosimetry cross sections and investigates the quality of the current dosimetry cross section evaluations by examining calculated-to-experimental ratios in neutron benchmark fields. In recent years more nuclear-related technical areas are placing an emphasis on uncertainty quantification. With the availability of model-based cross sections and covariance matrices produced by nuclear data codes, some nuclear-related communities are considering the role these covariance matrices should play. While funding within the dosimetry community for cross section evaluations has been very meager, other areas, such as the solar-related astrophysics community and the US Nuclear Criticality Safety Program, have been supporting research in the area of neutron cross sections. The Cross Section Evaluation Working Group (CSEWG) is responsible for the creation and maintenance of the ENDF/B library which has been the mainstay for the reactor dosimetry community. Given the new trends in cross section evaluations, this paper explores the path forward for the US nuclear reactor dosimetry community and its use of the ENDF/B cross-sections. The major concern is maintenance of the sufficiency and accuracy of the uncertainty estimate when used for dosimetry applications. The two major areas of deficiency in the proposed ENDF/B approach are: 1) the use of unrelated covariance matrices in ENDF/B evaluations and 2) the lack of 'due consideration' of experimental data in the evaluation. (authors)

  13. Absolute Differential Positronium-Formation Cross Sections.

    PubMed

    Shipman, M; Armitage, S; Beale, J; Brawley, S J; Fayer, S E; Garner, A J; Leslie, D E; Van Reeth, P; Laricchia, G

    2015-07-17

    The first absolute experimental determinations of the differential cross sections for the formation of ground-state positronium are presented for He, Ar, H2, and CO2 near 0°. Results are compared with available theories. The ratio of the differential and integrated cross sections for the targets exposes the higher propensity for forward emission of positronium formed from He and H2. PMID:26230792

  14. Neutron capture cross sections from Surrogate measurements

    NASA Astrophysics Data System (ADS)

    Escher, J. E.; Dietrich, F. S.; Scielzo, N. D.

    2010-03-01

    The prospects for determining cross sections for compound-nuclear neutron-capture reactions from Surrogate measurements are investigated. Calculations as well as experimental results are presented that test the Weisskopf-Ewing approximation, which is employed in most analyses of Surrogate data. It is concluded that, in general, one has to go beyond this approximation in order to obtain (n,?) cross sections of sufficient accuracy for most astrophysical and nuclear-energy applications.

  15. Fission cross section measurements at LANSCE

    NASA Astrophysics Data System (ADS)

    Tovesson, Fredrik; Hill, Tony

    2009-10-01

    Neutron induced fission cross sections of actinides are measured at the Los Alamos Neutron Science Center (LANSCE) in support of the Advanced Fuel Cycle Initiative (AFCI) and the National Nuclear Security Administration (NNSA). Nuclear technologies are increasingly dependent on advanced simulations for design and licensing requirements, and nuclear cross section data are important input parameters for the simulation tools. Fast nuclear reactor and stockpile stewardship applications often share nuclear data needs and requirements, and the LANSCE neutron source is ideal for measuring many of these data. The fission cross section measurements are guided by sensitivity studies performed in support of the AFCI program, as well as requests from NNSA. Recent results for the Pu-239 and Pu-241 fission cross sections from 0.01 eV to 200 MeV will be presented, and the discrepancy with current evaluations of the Pu-241 fission cross section discussed. Ongoing activities to extend the fission program will be presented, such as the development of a Time Projection Chamber (TPC) to significantly improve the experimental accuracies in fission cross section measurements.

  16. Parameterized Cross Sections for Pion Production in Proton-Proton Collisions

    NASA Technical Reports Server (NTRS)

    Blattnig, Steve R.; Swaminathan, Sudha R.; Kruger, Adam T.; Ngom, Moussa; Norbury, John W.; Tripathi, R. K.

    2000-01-01

    An accurate knowledge of cross sections for pion production in proton-proton collisions finds wide application in particle physics, astrophysics, cosmic ray physics, and space radiation problems, especially in situations where an incident proton is transported through some medium and knowledge of the output particle spectrum is required when given the input spectrum. In these cases, accurate parameterizations of the cross sections are desired. In this paper much of the experimental data are reviewed and compared with a wide variety of different cross section parameterizations. Therefore, parameterizations of neutral and charged pion cross sections are provided that give a very accurate description of the experimental data. Lorentz invariant differential cross sections, spectral distributions, and total cross section parameterizations are presented.

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

    NASA Technical Reports Server (NTRS)

    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.

  18. Undergraduate Measurements of Neutron Cross Sections

    NASA Astrophysics Data System (ADS)

    Hicks, S. F.; Vanhoy, J. R.; French, A. J.; Santonil, Z. C.; Crider, B. P.; Peters, E. E.; McEllistrem, M. T.; Prados-Estévez, F. M.; Ross, T. J.; Yates, S. W.

    Undergraduate students at the University of Dallas have investigated basic properties of nuclei through ?-ray and neutron spectroscopy following neutron scattering. The former has been used primarily for nuclear structure investigations, while the latter has been used to measure neutron scattering cross sections important for fission reactor applications. A series of (n,n') and (n,n'?) measurements have been made on 54Fe and 56Fe to determine neutron cross sections for scattering to excited levels in these nuclei. The former provides the cross sections directly and the latter are used to deduce inelastic neutron scattering cross sections by measuring the ?-ray production cross sections to states not easily resolved in neutron spectroscopy. All measurements have been completed at the University of Kentucky Accelerator Laboratory using a 7-MV Model CN Van de Graaff accelerator, along with the neutron production and neutron and ?-ray detection systems located there. Students participate in accelerator operation, experimental setup, data acquisition, and data analyses. An overview of the research program and student contributions is presented.

  19. Elastic and total cross sections for simple biomolecules in the intermediate energy range

    NASA Astrophysics Data System (ADS)

    Gupta, Dhanoj; Naghma, Rahla; Antony, Bobby

    2015-09-01

    The elastic and total cross sections for formaldehyde, acetaldehyde, acetone, 2-butanone and formamide are calculated using the spherical complex optical potential formalism in the intermediate energy range from 50 eV to 10 keV. These cross sections find application to various fields like radiation damage and biological sciences. The present results are compared with the available experimental and theoretical data and are found to give excellent agreement. The elastic cross sections reported for most of the targets in the present energy range are done for the first time. The energy dependence of the contribution of ionization and elastic cross section with respect to the total cross section and the correlation of total cross section with polarizability of the molecules are also studied.

  20. Top differential cross section measurements (Tevatron)

    SciTech Connect

    Jung, Andreas W.

    2012-01-01

    Differential cross sections in the top quark sector measured at the Fermilab Tevatron collider are presented. CDF used 2.7 fb{sup -1} of data and measured the differential cross section as a function of the invariant mass of the t{bar t} system. The measurement shows good agreement with the standard model and furthermore is used to derive limits on the ratio {kappa}/M{sub Pl} for gravitons which decay to top quarks in the Randall-Sundrum model. D0 used 1.0 fb{sup -1} of data to measure the differential cross section as a function of the transverse momentum of the top-quark. The measurement shows a good agreement to the next-to-leading order perturbative QCD prediction and various other standard model predictions.

  1. Algorithmic analysis of quantum radar cross sections

    NASA Astrophysics Data System (ADS)

    Lanzagorta, Marco; Venegas-Andraca, Salvador

    2015-05-01

    Sidelobe structures on classical radar cross section graphs are a consequence of discontinuities in the surface currents. In contrast, quantum radar theory states that sidelobe structures on quantum radar cross section graphs are due to quantum interference. Moreover, it is conjectured that quantum sidelobe structures may be used to detect targets oriented off the specular direction. Because of the high data bandwidth expected from quantum radar, it may be necessary to use sophisticated quantum signal analysis algorithms to determine the presence of stealth targets through the sidelobe structures. In this paper we introduce three potential quantum algorithmic techniques to compute classical and quantum radar cross sections. It is our purpose to develop a computer science-oriented tool for further physical analysis of quantum radar models as well as applications of quantum radar technology in various fields.

  2. Absorption cross sections of stratospheric molecules

    NASA Technical Reports Server (NTRS)

    Hudson, R. D.

    1974-01-01

    Two classes of molecular species must be considered in a calculation of photochemical rates in the stratosphere. The first class consists of molecular oxygen and ozone, while the second class contains the remainder of the minor constituents. If accurate values of the transmitted fluxes are required at large optical depths, the cross sections for molecular oxygen and ozone must be known to within a few per cent at least. On the other hand, the photochemical rates for the minor species are given simply by the relevant cross sections. A review of published cross sections is presented, giving attention to molecular oxygen, ozone, nitric oxide, nitrogen dioxide, nitrous oxide, nitric acid, ammonia, water vapor, hydrogen peroxide, carbon monoxide, carbon dioxide, and sulfur dioxide.

  3. Photodissociation in Quantum Chaotic Systems: Random Matrix Theory of Cross-Section Fluctuations

    E-print Network

    Yan V. Fyodorov; Yoram Alhassid

    1998-02-10

    Using the random matrix description of open quantum chaotic systems we calculate in closed form the universal autocorrelation function and the probability distribution of the total photodissociation cross section in the regime of quantum chaos.

  4. Photon scattering cross sections of H2 and He measured with synchrotron radiation

    NASA Technical Reports Server (NTRS)

    Ice, G. E.

    1977-01-01

    Total (elastic + inelastic) differential photon scattering cross sections have been measured for H2 gas and He, using an X-ray beam. Absolute measured cross sections agree with theory within the probable errors. Relative cross sections (normalized to theory at large S) agree to better than one percent with theoretical values calculated from wave functions that include the effect of electron-electron Coulomb correlation, but the data deviate significantly from theoretical independent-particle (e.g., Hartree-Fock) results. The ratios of measured absolute He cross sections to those of H2, at any given S, also agree to better than one percent with theoretical He-to-H2 cross-section ratios computed from correlated wave functions. It appears that photon scattering constitutes a very promising tool for probing electron correlation in light atoms and molecules.

  5. Optical Model and Cross Section Uncertainties

    SciTech Connect

    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.

  6. Covariance Evaluation Methodology for Neutron Cross Sections

    SciTech Connect

    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.

  7. Neutron capture cross section of 136 Xe

    NASA Astrophysics Data System (ADS)

    Daugherty, Sean; Albert, Joshua; Johnson, Tessa; O'Conner, Thomasina; Kaufman, Lisa

    2015-04-01

    136 Xe is an important 0 ??? candidate, studied in experiments such as EXO-200 and, in the future, nEXO. These experiments require a precise study of neutron capture for their background models. The neutron capture cross section of 136 Xe has been measured at the Detector for Advanced Capture Experiments (DANCE) at the Los Alamos Neutron Science Center. A neutron beam ranging from thermal energy to 100 keV was incident on a gas cell filled with isotopically pure 136 Xe . We will discuss the measurement of partial neutron capture cross sections at thermal and first neutron resonance energies along with corresponding capture gamma cascades.

  8. Neutron Capture Cross Section of 239Pu

    NASA Astrophysics Data System (ADS)

    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,?) 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,?) measurements on 239Pu in the keV region. Fission coincidences were measured with a PPAC and used to characterize the prompt fission ?-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,?) cross section measurement well into the keV region.

  9. Electron impact double ionization cross-sections of heavy elements

    NASA Astrophysics Data System (ADS)

    Talukder, M. R.; Shahjahan, M.; Uddin, M. A.

    2012-01-01

    A user-friendly semi-empirical formula for the description of electron impact double ionization cross-sections of heavy Sc1+, Ti5+, Fe6+, Ni3+, Ga, Kr4+, Rb1+, Mo3+, Ag, Sb1+, In, Xe4+, Cs1+, Ba2+, Pr3+, Sm6+, W6+, Hg, Pb, Bi1+, and U targets for the incident electron energies from threshold to 106 eV is proposed. The formula contains both the direct and indirect components leading to double ionization. The parameters of the model are determined from the best fit to the available experimental cross-sections using a nonlinear least-squares fitting computer program. It was noticed that the formula represents the experimental data for a fairly wide range of atomic heavy species over a wide range of incident energies.

  10. (? ,? ) cross section measurements in the region of light p nuclei

    NASA Astrophysics Data System (ADS)

    Quinn, S. J.; Spyrou, A.; Simon, A.; Battaglia, A.; Bowers, M.; Bucher, B.; Casarella, C.; Couder, M.; DeYoung, P. A.; Dombos, A. C.; Görres, J.; Kontos, A.; Li, Q.; Long, A.; Moran, M.; Paul, N.; Pereira, J.; Robertson, D.; Smith, K.; Smith, M. K.; Stech, E.; Talwar, R.; Tan, W. P.; Wiescher, M.

    2015-10-01

    The 90Zr(? ,? )94Mo,92Zr(? ,? )96Mo, and 74Ge(? ,? )78Se reaction cross sections were measured for the first time in an effort to expand the existing experimental database for (? ,? ) reactions relevant for the production of p nuclei in the universe. In particular, the 90Zr(? ,? )94Mo reaction was identified by a sensitivity study for its potential impact on the ? -process mass flow in the region of light p nuclei. The measurements were performed for energies E?=9.5 - 12.0 MeV at the University of Notre Dame using the SuN detector and the ? -summing technique. The results are compared to theoretical calculations from the talys and non-smoker nuclear reaction codes, and it is shown that the data greatly reduce the uncertainty in the cross section for the measured energies. The talys parameters that provide the best description of the experimental data are reported.

  11. Inclusive parton cross sections in photoproduction and photon structure

    NASA Astrophysics Data System (ADS)

    Ahmed, T.; Aid, S.; Andreev, V.; Andrieu, B.; Appuhn, R.-D.; Arpagaus, M.; Babaev, A.; Baehr, J.; Bán, J.; Ban, Y.; Baranov, P.; Barrelet, E.; Bartel, W.; Barth, M.; Bassler, U.; Beck, H. P.; Behrend, H.-J.; Belousov, A.; Berger, Ch.; Bernardi, G.; Bernet, R.; Bertrand-Coremans, G.; Besançon, M.; Beyer, R.; Biddulph, P.; Bispham, P.; Bizot, J. C.; Blobel, V.; Borras, K.; Botterweck, F.; Boudry, V.; Braemer, A.; Brasse, F.; Braunschweig, W.; Brisson, V.; Bruncko, D.; Brune, C.; Buchholz, R.; Büngener, L.; Bürger, J.; Büsser, F. W.; Buniatian, A.; Burke, S.; Burton, M.; Buschhorn, G.; Campbell, A. J.; Carli, T.; Charles, F.; Charlet, M.; Clarke, D.; Clegg, A. B.; Clerbaux, B.; Colombo, M.; Contreras, J. G.; Cormack, C.; Coughlan, J. A.; Courau, A.; Coutures, Ch.; Cozzika, G.; Criegee, L.; Cussans, D. G.; Cvach, J.; Dagoret, S.; Dainton, J. B.; Dau, W. D.; Daum, K.; David, M.; Delcourt, B.; Del Buono, L.; De Roeck, A.; De Wolf, E. A.; Di Nezza, P.; Dollfus, C.; Dowell, J. D.; Dreis, H. B.; Droutskoi, A.; Duboc, J.; Düllmann, D.; Dünger, O.; Duhm, H.; Ebert, J.; Ebert, T. R.; Eckerlin, G.; Efremenko, V.; Egli, S.; Ehrlichmann, H.; Eichenberger, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellison, R. J.; Elsen, E.; Erdmann, M.; Erdmann, W.; Evrard, E.; Favart, L.; Fedotov, A.; Feeken, D.; Felst, R.; Feltesse, J.; Ferencei, J.; Ferrarotto, F.; Flamm, K.; Fleischer, M.; Flieser, M.; Flügge, G.; Fomenko, A.; Fominykh, B.; Forbush, M.; Formánek, J.; Foster, J. M.; Franke, G.; Fretwurst, E.; Gabathuler, E.; Gabathuler, K.; Gamerdinger, K.; Garvey, J.; Gayler, J.; Gebauer, M.; Gellrich, A.; Genzel, H.; Gerhards, R.; Goerlach, U.; Goerlich, L.; Gogitidze, N.; Goldberg, M.; Goldner, D.; Gonzalez-Pineiro, B.; Gorelov, I.; Goritchev, P.; Grab, C.; Grässler, H.; Grässler, R.; Greenshaw, T.; Grindhammer, G.; Gruber, A.; Gruber, C.; Haack, J.; Haidt, D.; Hajduk, L.; Hamon, O.; Hampel, M.; Hanlon, E. M.; Hapke, M.; Haynes, W. J.; Heatherington, J.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Herynek, I.; Hess, M. F.; Hildesheim, W.; Hill, P.; Hiller, K. H.; Hilton, C. D.; Hladký, J.; Hoeger, K. C.; Höppner, M.; Horisberger, R.; Hudgson, V. L.; Huet, Ph.; Hütte, M.; Hufnagel, H.; Ibbotson, M.; Itterbeck, H.; Jabiol, M.-A.; Jacholkowska, A.; Jacobsson, C.; Jaffre, M.; Janoth, J.; Jansen, T.; Jönsson, L.; Johnson, D. P.; Johnson, L.; Jung, H.; Kalmus, P. I. P.; Kant, D.; Kaschowitz, R.; Kasselmann, P.; Kathage, U.; Katzy, J.; Kaufmann, H. H.; Kazarian, S.; Kenyon, I. R.; Kermiche, S.; Keuker, C.; Kiesling, C.; Klein, M.; Kleinwort, C.; Knies, G.; Ko, W.; Köhler, T.; Köhne, J. H.; Kolanoski, H.; Kole, F.; Kolya, S. D.; Korbel, V.; Korn, M.; Kostka, P.; Kotelnikov, S. K.; Krämerkämper, T.; Krasny, M. W.; Krehbiel, H.; Krücker, D.; Krüger, U.; Krüner-Marquis, U.; Kubenka, J. P.; Küster, H.; Kuhlen, M.; Kur?a, T.; Kurzhöfer, J.; Kuznik, B.; Lacour, D.; Lamarche, F.; Lander, R.; Landon, M. P. J.; Lange, W.; Lanius, P.; Laporte, J.-F.; Lebedev, A.; Leverenz, C.; Levonian, S.; Ley, Ch.; Lindner, A.; Lindström, G.; Link, J.; Linsel, F.; Lipinski, J.; List, B.; Lobo, G.; Loch, P.; Lohmander, H.; Lomas, J.; Lopez, G. C.; Lubimov, V.; Lüke, D.; Magnussen, N.; Malinovski, E.; Mani, S.; Mara?ek, R.; Marage, P.; Marks, J.; Marshall, R.; Martens, J.; Martin, R.; Martyn, H.-U.; Martyniak, J.; Masson, S.; Mavroidis, T.; Maxfield, S. J.; McMahon, S. J.; Mehta, A.; Meier, K.; Mercer, D.; Merz, T.; Meyer, C. A.; Meyer, H.; Meyer, J.; Migliori, A.; Mikocki, S.; Milstead, D.; Moreau, F.; Morris, J. V.; Mroczko, E.; Müller, G.; Müller, K.; Murín, P.; Nagovizin, V.; Nahnhauer, R.; Naroska, B.; Naumann, Th.; Newman, P. R.; Newton, D.; Neyret, D.; Nguyen, H. K.; Nicholls, T. C.; Niebergall, F.; Niebuhr, C.; Niedzballa, Ch.; Nisius, R.; Nowak, G.; Noyes, G. W.; Nyberg-Werther, M.; Oakden, M.; Oberlack, H.; Obrock, U.; Olsson, J. E.; Ozerov, D.; Panaro, E.; Panitch, A.; Pascaud, C.; Patel, G. D.; Peppel, E.; Perez, E.; Phillips, J. P.; Pichler, Ch.; Pieuchot, A.; Pitzl, D.; Pope, G.; Prell, S.; Prosi, R.; Rabbertz, K.; Rädel, G.; Raupach, F.; Reimer, P.; Reinshagen, S.; Ribarics, P.; Rick, H.; Riech, V.; Riedlberger, J.; Riess, S.; Rietz, M.; Rizvi, E.; Robertson, S. M.; Robmann, P.; Roloff, H. E.; Roosen, R.; Rosenbauer, K.; Rostovtsev, A.; Rouse, F.; Royon, C.; Rüter, K.; Rusakov, S.; Rybicki, K.; Rylko, R.; Sahlmann, N.; Salesch, S. G.; Sanchez, E.; Sankey, D. P. C.; Schacht, P.; Schiek, S.; Schleper, P.; von Schlippe, W.; Schmidt, C.; Schmidt, D.; Schmidt, G.; Schöning, A.; Schröder, V.; Schuhmann, E.; Schwab, B.; Schwind, A.; Sefkow, F.; Seidel, M.; Sell, R.; Semenov, A.; Shekelyan, V.; Sheviakov, I.; Shooshtari, H.; Shtarkov, L. N.; Siegmon, G.; Siewert, U.; Sirois, Y.; Skillicorn, I. O.; Smirnov, P.

    1995-02-01

    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.

  12. 30 CFR 779.25 - Cross sections, maps, and plans.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Cross sections, maps, and plans. (a) The application shall...cross sections, maps, and plans showing— (1) Elevations...Location of surface water bodies such as streams, lakes, ponds...Cross sections, maps and plans included in a permit...

  13. Lidar Bacscatter Cross-Section Radar Bacscatter Cross-Section Mixed Phase

    E-print Network

    Eloranta, Edwin W.

    Lidar Bacscatter Cross-Section Radar Bacscatter Cross-Section Mixed Phase Lidar-Radar Effective Size Mixed Phase Effective Size Number Density Lidar Water BSCS Lidar Ice BSCS Radar Water BSCS Radar Ice BSCS Water Content Ice Phase Lidar-Radar Effective Size Ice Phase Effective Size Ice Number

  14. Testing (Validating?) Cross Sections with ICSBEP Benchmarks

    SciTech Connect

    Kahler, Albert C. III

    2012-06-28

    We discuss how to use critical benchmarks from the International Handbook of Evaluated Criticality Safety Benchmark Experiments to determine the applicability of specific cross sections to the end-user's problem of interest. Particular attention is paid to making sure the selected suite of benchmarks includes the user's range of applicability (ROA).

  15. Cross Sections From Scalar Field Theory

    NASA Technical Reports Server (NTRS)

    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.

  16. Cross-Sections: An Application of Matrices.

    ERIC Educational Resources Information Center

    Browne, Nicholas

    1984-01-01

    Examines the study of transformations which result from cross-sections of a prism. The study involves some model-making, which in turn introduces some new problems of drawing and construction. The material is presented with the practicalities of classroom teaching in mind. (Author/JN)

  17. Log ASCII Standard (LAS) Files for Geophysical (Gamma Ray) Wireline Well Logs and Their Application to Geologic Cross Section C-C' Through the Central Appalachian Basin

    USGS Publications Warehouse

    Trippi, Michael H.; Crangle, Robert D., Jr.

    2009-01-01

    U.S. Geological Survey (USGS) regional geologic cross section C-C' (Ryder and others, 2008) displays key stratigraphic intervals in the central Appalachian basin. For this cross section, strata were correlated by using descriptions of well cuttings and gamma ray well log traces. This report summarizes the procedures used to convert gamma ray curves on paper well logs to the digital Log ASCII (American Standard Code for Information Interchange) Standard (LAS) format using the third-party software application Neuralog. The procedures could be used with other geophysical wireline logs also. The creation of digital LAS files from paper well logs by using Neuralog is very helpful, especially when dealing with older logs with limited or nonexistent digital data. The LAS files from the gamma ray logs of 11 wells used to construct cross section C-C' are included in this report. They may be downloaded from the index page as a single ZIP file.

  18. Towards Reliable Cross Sections for National Security Applications

    SciTech Connect

    Escher, J E; Dietrich, F S; Nobre, G A; Thompson, I J

    2011-02-24

    Stockpile stewardship requires the description of weapons performance without resorting to underground nuclear testing. In the earlier tests, selected isotopes were used as detectors, and recovered after irradiation. Aspects of nuclear device performance were inferred by comparing the measured isotopic ratios to those predicted from simulations. The reaction flows that produce the final isotopic distributions proceed through regions of the nuclear chart that include unstable nuclei. Presently, improved nuclear data input is required to reanalyze prior tests and to certify the stockpile's reliability and safety. Many important cross sections are unknown, as is shown in the example of the Yttrium reaction network (Figure 1). The relevant reactions include (n,2n), (n,n'), (n,gamma), (n,p) and other charged-particle emitting reactions. The cross sections have to be calculated or inferred from indirect measurements. In both cases, reliable optical models that are valid a few nucleons away from stability are needed. The UNEDF Nuclear Reaction activities address this need by combining nuclear-structure input from UNEDF structure calculations with modern reaction theory and large-scale computational capabilities to develop microscopic nucleon-nucleus optical potentials that can be extrapolated to unstable nuclei. In addition, the reaction calculation tools and optical models developed in this context are proving valuable for planning and interpreting indirect (surrogate) measurements of the required cross sections.

  19. Humeral cross-sectional shape in suspensory primates and sloths.

    PubMed

    Patel, Biren A; Ruff, Christopher B; Simons, Erin L R; Organ, Jason M

    2013-04-01

    Studies on the cross-sectional geometry of long bones in African apes have documented that shape ratios derived from second moments of area about principle axes (e.g., Imax /Imin ) are often correlated with habitual locomotor behaviors. For example, humeral cross-sections tend to appear more circular in more arboreal and forelimb suspensory chimpanzees compared with terrestrial quadrupedal gorillas. These data support the hypothesis that cross-sections that are more circular in shape are adapted for multidirectional loading regimes and bending moments encountered when using acrobatic locomotor behaviors. Whether a more circular humerus reflects greater use of forelimb suspension in other primates and nonprimate mammals is unknown. In this study, cross-sections at or near midshaft of the humerus were obtained from anthropoid primates that differ in their use of forelimb suspension, as well as from two genera of suspensory sloths. Imax /Imin ratios were compared within and between groups, and correlations were made with behavioral data. In broad comparisons, observed differences in morphology follow predicted patterns. Humeri of suspensory sloths are circular. Humeri of the more suspensory hominoids tend to be more circular than those of quadrupedal taxa. Humeri of the suspensory atelines are similar to hominoids, while those of Cebus are more like nonsuspensory cercopithecoids. There is, however, considerable overlap between taxa and within finer comparisons variation between species are not in the predicted direction. Thus, although Imax /Imin ratios of the humerus are informative for characterizing generalized locomotor modes (i.e., forelimb suspensory vs. quadrupedal), additional structural information is needed for more fine-grained assessments of locomotion. PMID:23408647

  20. Absolute np and pp Cross Section Determinations Aimed At Improving The Standard For Cross Section Measurements

    SciTech Connect

    Laptev, A. B.; Haight, R. C.; Tovesson, F.; Arndt, R. A.; Briscoe, W. J.; Paris, M. W.; Strakovsky, I. I.; Workman, R. L.

    2011-06-01

    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 1 GeV are determined based on partial-wave analyses (PWAs) of nucleon-nucleon scattering data. These cross sections are compared with the most recent ENDF/B-VII.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.

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

    SciTech Connect

    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.

  2. Quantifying and predicting interpretational uncertainty in cross-sections

    NASA Astrophysics Data System (ADS)

    Randle, Charles; Bond, Clare; Monaghan, Alison; Lark, Murray

    2015-04-01

    Cross-sections are often constructed from data to create a visual impression of the geologist's interpretation of the sub-surface geology. However as with all interpretations, this vision of the sub-surface geology is uncertain. We have designed and carried out an experiment with the aim of quantifying the uncertainty in geological cross-sections created by experts interpreting borehole data. By analysing different attributes of the data and interpretations we reflect on the main controls on uncertainty. A group of ten expert modellers at the British Geological Survey were asked to interpret an 11.4 km long cross-section from south-east Glasgow, UK. The data provided consisted of map and borehole data of the superficial deposits and shallow bedrock. Each modeller had a unique set of 11 boreholes removed from their dataset, to which their interpretations of the top of the bedrock were compared. This methodology allowed quantification of how far from the 'correct answer' each interpretation is at 11 points along each interpreted cross-section line; through comparison of the interpreted and actual bedrock elevations in the boreholes. This resulted in the collection of 110 measurements of the error to use in further analysis. To determine the potential control on uncertainty various attributes relating to the modeller, the interpretation and the data were recorded. Modellers were asked to fill out a questionnaire asking for information; such as how much 3D modelling experience they had, and how long it took them to complete the interpretation. They were also asked to record their confidence in their interpretations graphically, in the form of a confidence level drawn onto the cross-section. Initial analysis showed the majority of the experts' interpreted bedrock elevations within 5 metres of those recorded in the withheld boreholes. Their distribution is peaked and symmetrical about a mean of zero, indicating that there was no tendency for the experts to either under or over estimate the elevation of the bedrock. More complex analysis was completed in the form of linear mixed effects modelling. The modelling was used to determine if there were any correlations between the error and any other parameter recorded in the questionnaire, section or the initial dataset. This has resulted in the determination of both data based and interpreter based controls on uncertainty, adding insight into how uncertainty can be predicted, as well as how interpretation workflows can be improved. Our results will inform further experiments across a wide variety of geological situations to build understanding and best practice workflows for cross-section interpretation to reduce uncertainty.

  3. Photonuclear Reaction Cross Sections for Gallium Isotopes

    E-print Network

    Akkoyun, Serkan

    2014-01-01

    The photon induced reactions which are named as photonuclear reactions have a great importance in many field of nuclear, radiation physics and related fields. Since we have planned to perform photonuclear reaction on gallium target with bremmstrahlung photons from clinical linear accelerator in the future, the cross-sections of neutron (photo-neutron ({\\gamma},xn)) and proton (photo-proton ({\\gamma},xn)) productions after photon activation have been calculated by using TALYS 1.2 computer code in this study. The target nucleus has been considered gallium which has two stable isotopes, 69Ga and 71Ga. According to the results, we have seen that the calculations are in harmony in the limited literature values. Furthermore, the pre-equilibrium and compound process contributions to the total cross-section have been investigated.

  4. Electron-collision cross sections for iodine

    SciTech Connect

    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.

    2011-04-15

    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.

  5. Electron capture cross sections for stellar nucleosynthesis

    E-print Network

    P. G. Giannaka; T. S. Kosmas

    2015-02-25

    In the first stage of this work, we perform detailed calculations for the cross sections of the electron capture on nuclei under laboratory conditions. Towards this aim we exploit the advantages of a refined version of the proton-neutron quasi-particle random-phase approximation (pn-QRPA) and carry out state-by-state evaluations of the rates of exclusive processes that lead to any of the accessible transitions within the chosen model space. In the second stage of our present study, we translate the above mentioned $e^-$-capture cross sections to the stellar environment ones by inserting the temperature dependence through a Maxwell-Boltzmann distribution describing the stellar electron gas. As a concrete nuclear target we use the $^{66}Zn$ isotope, which belongs to the iron group nuclei and plays prominent role in stellar nucleosynthesis at core collapse supernovae environment.

  6. Photonuclear Reaction Cross Sections for Gallium Isotopes

    E-print Network

    Serkan Akkoyun; Tuncay Bayram

    2014-09-08

    The photon induced reactions which are named as photonuclear reactions have a great importance in many field of nuclear, radiation physics and related fields. Since we have planned to perform photonuclear reaction on gallium target with bremmstrahlung photons from clinical linear accelerator in the future, the cross-sections of neutron (photo-neutron ({\\gamma},xn)) and proton (photo-proton ({\\gamma},xn)) productions after photon activation have been calculated by using TALYS 1.2 computer code in this study. The target nucleus has been considered gallium which has two stable isotopes, 69Ga and 71Ga. According to the results, we have seen that the calculations are in harmony in the limited literature values. Furthermore, the pre-equilibrium and compound process contributions to the total cross-section have been investigated.

  7. Fusion cross sections and the new dynamics

    SciTech Connect

    Swiatecki, W.J.

    1981-05-01

    The prediction of the need for an extra push over the interaction barrier in order to make the heavier nuclei fuse is made the basis of a simple algebraic theory for the energy-dependence of the fusion cross-section. A comparison with recent experiments promises to provide a quantitative test of the New Dynamics (the theory of macroscopic nuclear shape evolutions based on the one-body dissipation concept).

  8. Fusion cross sections measurements with MUSIC

    NASA Astrophysics Data System (ADS)

    Carnelli, P. F. F.; Fernández Niello, J. O.; Almaraz-Calderon, S.; Rehm, K. E.; Albers, M.; Digiovine, B.; Esbensen, H.; Henderson, D.; Jiang, C. L.; Nusair, O.; Palchan-Hazan, T.; Pardo, R. C.; Ugalde, C.; Paul, M.; Alcorta, M.; Bertone, P. F.; Lai, J.; Marley, S. T.

    2014-09-01

    The interaction between exotic nuclei plays an important role for understanding the reaction mechanism of the fusion processes as well as for the energy production in stars. With the advent of radioactive beams new frontiers for fusion reaction studies have become accessible. We have performed the first measurements of the total fusion cross sections in the systems 10 , 14 , 15C + 12C using a newly developed active target-detector system (MUSIC). Comparison of the obtained cross sections with theoretical predictions show a good agreement in the energy region accessible with existing radioactive beams. This type of comparison allows us to calibrate the calculations for cases that cannot be studied in the laboratory with the current experimental capabilities. The high efficiency of this active detector system will allow future measurements with even more neutron-rich isotopes. The interaction between exotic nuclei plays an important role for understanding the reaction mechanism of the fusion processes as well as for the energy production in stars. With the advent of radioactive beams new frontiers for fusion reaction studies have become accessible. We have performed the first measurements of the total fusion cross sections in the systems 10 , 14 , 15C + 12C using a newly developed active target-detector system (MUSIC). Comparison of the obtained cross sections with theoretical predictions show a good agreement in the energy region accessible with existing radioactive beams. This type of comparison allows us to calibrate the calculations for cases that cannot be studied in the laboratory with the current experimental capabilities. The high efficiency of this active detector system will allow future measurements with even more neutron-rich isotopes. This work is supported by the U.S. DOE Office of Nuclear Physics under Contract No. DE-AC02-06CH11357 and the Universidad Nacional de San Martin, Argentina, Grant SJ10/39.

  9. How to Calculate Colourful Cross Sections Efficiently

    SciTech Connect

    Gleisberg, Tanju; Hoeche, Stefan; Krauss, Frank

    2008-09-03

    Different methods for the calculation of cross sections with many QCD particles are compared. To this end, CSW vertex rules, Berends-Giele recursion and Feynman-diagram based techniques are implemented as well as various methods for the treatment of colours and phase space integration. We find that typically there is only a small window of jet multiplicities, where the CSW technique has efficiencies comparable or better than both of the other two methods.

  10. Inclusive jet cross section measurement at CDF

    SciTech Connect

    Pagliarone, C.

    1996-08-01

    The CDF Collaboration has measured the inclusive jet cross section using 1992-93 collider data at 1.8 TeV. The CDF measurement is in very good agreement with NLO QCD predictions for transverse energies (E{sub T}) below 200 GeV. However, it is systematically higher than NLO QCD predictions for E{sub T} above 200 GeV.

  11. {sup 231}Pa photofission cross section

    SciTech Connect

    Soldatov, A.S.; Rudnikov, V.E.; Smirenkin, G.N.

    1995-12-01

    The measurements of the {sup 231}Pa yield and cross section photofission in the energy range 7-9 MeV are presented. These measurements are a continuation of similar measurements performed for the {gamma}-ray energy range 4.8-7 MeV. The entire collection of experimental data which combine the results obtained in the present work and in Ref. 1 was analyzed.

  12. Inelastic cross section measurements at LHC

    E-print Network

    Bindi, M; The ATLAS collaboration

    2012-01-01

    The dependence of the rate of proton–proton interactions on the centre-of-mass collision energy, ?s, is of fundamental importance for both hadron collider physics and particle astrophysics. The dependence cannot yet be calculated from first principles; therefore, experimental measurements are needed. Here we present the first measurements of the inelastic proton–proton interaction cross-section at a centre-of-mass energy, ?s, of 7 TeV using the ATLAS and CMS detectors at the Large Hadron Collider. For ATLAS the events are selected by requiring hits on scintillation counters mounted in the forward region of the detector. An inelastic cross-section of 60.3 ± 2.1 mb is measured for ? > 5×10?6, where ? is calculated from the invariant mass, MX, of hadrons selected using the largest rapidity gap in the event. For diffractive events, this corresponds to requiring at least one of the dissociation masses to be larger than 15.7 GeV. For CMS a new method to measure the inelastic pp cross section ha...

  13. Averaging cross section data so we can fit it

    SciTech Connect

    Brown, D.

    2014-10-23

    The 56Fe cross section we are interested in have a lot of fluctuations. We would like to fit the average of the cross section with cross sections calculated within EMPIRE. EMPIRE is a Hauser-Feshbach theory based nuclear reaction code, requires cross sections to be smoothed using a Lorentzian profile. The plan is to fit EMPIRE to these cross sections in the fast region (say above 500 keV).

  14. Automatic Computation of Cross Sections in HEP

    E-print Network

    F. Yuasa; J. Fujimoto; T. Ishikawa; M. Jimbo; T. Kaneko; K. Kato; S. Kawabata; T. Kon; Y. Kurihara; M. Kuroda; N. Nakazawa; Y. Shimizu; H. Tanaka

    2000-07-06

    For the study of reactions in High Energy Physics (HEP) automatic computation systems have been developed and are widely used nowadays. GRACE is one of such systems and it has achieved much success in analyzing experimental data. Since we deal with the cross section whose value can be given by calculating hundreds of Feynman diagrams, we manage the large scale calculation, so that effective symbolic manipulation, the treat of singularity in the numerical integration are required. The talk will describe the software design of GRACE system and computational techniques in the GRACE.

  15. Top Production Cross Sections at D0

    SciTech Connect

    Kvita, Jiri

    2009-07-01

    We report on measurements of the ttbar production cross section at a center-of-mass energy of 1.96 TeV at the D0 experiment during Run II of the Fermilab Tevatron collider. We use candidate events in lepton+jets and dilepton final states. In the most sensitive channel (lepton+jets channel), a neural network algorithm that uses lifetime information to identify b-quark jets is used to distinguish signal from background processes. We also present measurements of single top quark production at D0 using several multivariate techniques to separate signal from background.

  16. Radar cross section reduction by absorber covering

    NASA Technical Reports Server (NTRS)

    Li, H. J.; Farhat, N. H.; Shen, Y.

    1989-01-01

    Radar cross section (RCS) reduction by absorber covering is experimentally studied by employing microwave diversity imaging. Experimental results show that broadband absorber covering is not effective at reducing the co-polarized (the transmitting and receiving antennas have opposite sense of circular polarization) RCS of a plate when the incident wave approximates the edge-on direction but is effective at reducing the cross-polarized (both the transmitting and receiving antennas have the same sense of circular polarization) RCS for all incident directions. The surface current absorber covering is effective at reducing the nonspecular energy and multiple bounces regardless of the polarization status of the measurement.

  17. Measurement of actinide neutron cross sections

    SciTech Connect

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

    2003-06-15

    The maintenance of strong scientific expertise is criticalto the U.S. nuclear attribution community. It is particularly importantto train students in actinide chemistry and physics. Neutroncross-section data are vital components to strategies for detectingexplosives and fissile materials, and these measurements requireexpertise in chemical separations, actinide target preparation, nuclearspectroscopy, and analytical chemistry. At the University of California,Berkeley and the Lawrence Berkeley National Laboratory we have trainedstudents in actinide chemistry for many years. LBNL is a leader innuclear data and has published the Table of Isotopes for over 60 years.Recently, LBNL led an international collaboration to measure thermalneutron capture radiative cross sections and prepared the EvaluatedGamma-ray Activation File (EGAF) in collaboration with the IAEA. Thisfile of 35,000 prompt and delayed gamma ray cross-sections for allelements from Z=1-92 is essential for the neutron interrogation ofnuclear materials. LBNL has also developed new, high flux neutrongenerators and recently opened a 1010 n/s D+D neutron generatorexperimental facility.

  18. Neutronic Cross Section Calculations on Fluorine Nucleus

    NASA Astrophysics Data System (ADS)

    Kara, A.; Tel, E.

    2013-06-01

    Certain light nuclei such as Lithium (Li), Beryllium (Be), Fluorine (F) (which are known as FL?BE) and its molten salt compounds (LiF, BeF2 and NaF) can serve as a coolant which can be used at high temperatures without reaching a high vapor pressure. These molten salt compounds are also a good neutron moderator. In this study, cross sections of neutron induced reactions have been calculated for fluorine target nucleus. The new calculations on the excitation functions of 19F( n, 2n), 19F( n, p), 19F( n, xn), 19F( n, xp) have been made. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the full exciton model and the cascade exciton model. The equilibrium effects are calculated according to the Weisskopf-Ewing model. Also in the present work, the ( n, 2n) and ( n, p) reaction cross sections have calculated by using evaluated empirical formulas developed by Tel et al. at 14-15 MeV energy. The multiple pre-equilibrium mean free path constant from internal transition have been investigated for 19F nucleus. The obtained results have been discussed and compared with the available experimental data.

  19. Actinide Targets for Neutron Cross Section Measurements

    SciTech Connect

    John D. Baker; Christopher A. McGrath

    2006-10-01

    The Advanced Fuel Cycle Initiative (AFCI) and the Generation IV Reactor Initiative have demonstrated a lack of detailed neutron cross-sections for certain "minor" actinides, those other than the most common (235U, 238U, and 239Pu). For some closed-fuel-cycle reactor designs more than 50% of reactivity will, at some point, be derived from "minor" actinides that currently have poorly known or in some cases not measured (n,?) and (n,f) cross sections. A program of measurements under AFCI has begun to correct this. One of the initial hurdles has been to produce well-characterized, highly isotopically enriched, and chemically pure actinide targets on thin backings. Using a combination of resurrected techniques and new developments, we have made a series of targets including highly enriched 239Pu, 240Pu, and 242Pu. Thus far, we have electrodeposited these actinide targets. In the future, we plan to study reductive distillation to achieve homogeneous, adherent targets on thin metal foils and polymer backings. As we move forward, separated isotopes become scarcer, and safety concerns become greater. The chemical purification and electodeposition techniques will be described.

  20. Differential cross-section for positronium formation in electron-atomic hydrogen collisions

    NASA Technical Reports Server (NTRS)

    Drachman, R. J.; Omidvar, K.; Mcguire, J. H.

    1976-01-01

    The L=0 and 1 partial wave amplitudes obtained by a two-state coupled static approximation with correlation with the L greater than or equal to 2 Born amplitudes were combined to obtain the differential cross section for positronium formation in electron-atomic hydrogen collisions. For positron energies of 0.64 and 0.75 ryd, minima at the scattering angles of 57 deg and 51 deg are found. Total cross sections for positronium formation for low and intermediate impact energies are given. Measurement of the differential cross section for the process positron + helium yields positronium + helium ion for the detection of possible minima is suggested.

  1. Formalism for neutron cross section covariances in the resonance region using kernel approximation

    SciTech Connect

    Oblozinsky, P.; Cho,Y-S.; Matoon,C.M.; Mughabghab,S.F.

    2010-04-09

    We describe analytical formalism for estimating neutron radiative capture and elastic scattering cross section covariances in the resolved resonance region. We use capture and scattering kernels as the starting point and show how to get average cross sections in broader energy bins, derive analytical expressions for cross section sensitivities, and deduce cross section covariances from the resonance parameter uncertainties in the recently published Atlas of Neutron Resonances. The formalism elucidates the role of resonance parameter correlations which become important if several strong resonances are located in one energy group. Importance of potential scattering uncertainty as well as correlation between potential scattering and resonance scattering is also examined. Practical application of the formalism is illustrated on {sup 55}Mn(n,{gamma}) and {sup 55}Mn(n,el).

  2. Empirical formula on (n,(3)He) reaction cross sections at 14.6MeV neutrons.

    PubMed

    Yi?it, Mustafa

    2015-11-01

    The systematic behavior of the cross sections of (n,(3)He) nuclear reactions has been studied by various researches at neutron energy of 14.6MeV. A new empirical formula based on the Q-value dependence of the cross sections of the investigated reaction has been proposed. The cross sections obtained from the new formula are compared with the other proposed formulae results and the experimental data. It seems that the present formula based on the Q-value dependence provides the good description for cross sections of neutron-induced (n,(3)He) nuclear reactions at 14.6MeV. PMID:26218596

  3. First measurement of the charged current cross section at HERA

    NASA Astrophysics Data System (ADS)

    Ahmed, T.; Andreev, V.; Andrieu, B.; Appuhn, R.-D.; Arpagaus, M.; Babaev, A.; Bán, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Barth, M.; Bassler, U.; Beck, H. P.; Behrend, H.-J.; Belousov, A.; Berger, Ch.; Bergstein, H.; Bernardi, G.; Bernet, R.; Bertrand-Coremans, G.; Besançon, M.; Biddulph, P.; Bizot, J. C.; Blobel, V.; Borras, K.; Boudry, V.; Braemer, A.; Brasse, F.; Braunschweig, W.; Brisson, V.; Bruncko, D.; Brune, C.; Büngener, L.; Bürger, J.; Büsser, F. W.; Buniatian, A.; Burke, S.; Buschhorn, G.; Campbell, A. J.; Carli, T.; Charles, F.; Clarke, D.; Clegg, A. B.; Colombo, M.; Coughlan, J. A.; Courau, A.; Coutures, Ch.; Cozzika, G.; Criegee, L.; Cussans, D. G.; Cvach, J.; Dagoret, S.; Dainton, J. B.; Danilov, M.; Dann, A. W. E.; Dau, W. D.; Daum, K.; David, M.; Deffur, E.; Delcourt, B.; Del Buono, L.; De Roeck, A.; De Wolf, E.; Dollfus, C.; Dowell, J. D.; Dreis, H. B.; Duboc, J.; Düllmann, D.; Dünger, O.; Duhm, H.; Ebert, J.; Ebert, T. R.; Eckerlin, G.; Efremenko, V.; Egli, S.; Ehrlichmann, H.; Eichenberger, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellison, R. J.; Elsen, E.; Erdmann, M.; Evrard, E.; Favart, L.; Fedotov, A.; Feeken, D.; Felst, R.; Feltesse, J.; Ferencei, J.; Ferrarotto, F.; Flamm, K.; Flauger, W.; Fleischer, M.; Flieser, M.; Flügge, G.; Fomenko, A.; Fominykh, B.; Forbush, M.; Formánek, J.; Foster, J. M.; Franke, G.; Fretwurst, E.; Gabathuler, E.; Gamerdinger, K.; Garvey, J.; Gayler, J.; Gebauer, M.; Gellrich, A.; Genzel, H.; Gerhards, R.; Goerlach, U.; Goerlich, L.; Gogitidze, N.; Goldberg, M.; Goldner, D.; Goodall, A. M.; Gorelov, I.; Goritchev, P.; Grab, C.; Grässler, H.; Grässler, R.; Greenshaw, T.; Grindhammer, G.; Gruber, C.; Haack, J.; Haidt, D.; Hajduk, L.; Hamon, O.; Hampel, M.; Hanlon, E. M.; Hapke, M.; Haynes, W. J.; Heatherington, J.; Hedberg, V.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Herma, R.; Herynek, I.; Hildesheim, W.; Hill, P.; Hilton, C. D.; Hladký, J.; Hoeger, K. C.; Höppner, M.; Huet, Ph.; Hufnagel, H.; Ibbotson, M.; Itterbeck, H.; Jabiol, M.-A.; Jacholkowska, A.; Jacobsson, C.; Jaffre, M.; Janoth, J.; Jansen, T.; Jönsson, L.; Johannsen, K.; Johnson, D. P.; Johnson, L.; Jung, H.; Kalmus, P. I. P.; Kant, D.; Kazarian, S.; Kaschowitz, R.; Kasselmann, P.; Kathage, U.; Kaufmann, H. H.; Kenyon, I. R.; Kermiche, S.; Keuker, C.; Kiesling, C.; Klein, M.; Kleinwort, C.; Knies, G.; Ko, W.; Köhler, T.; Kolanoski, H.; Kole, F.; Kolya, S. D.; Korbel, V.; Korn, M.; Kostka, P.; Kotelnikov, S. K.; Krasny, M. W.; Krehbiel, H.; Krücker, D.; Krüger, U.; Krüner-Marquis, M.; Kubenka, J. P.; Küster, H.; Kuhlen, M.; Kur?a, T.; Kurzhöfer, J.; Kuznik, B.; Lacour, D.; Lamarche, F.; Lander, R.; Landon, M. P. J.; Lange, W.; Lanius, P.; Laporte, J. F.; Lebedev, A.; Leverenz, C.; Levonian, S.; Ley, Ch.; Lindner, A.; Lindström, G.; Linsel, F.; Lipinski, J.; Loch, P.; Lohmander, H.; Lopez, G. C.; Lüers, D.; Lüke, D.; Magnussen, N.; Malinovski, E.; Mani, S.; Marage, P.; Marshall, R.; Martens, J.; Martin, R.; Martyn, H.-U.; Martyniak, J.; Masson, S.; Mavroidis, A.; Maxfield, S. J.; McMahon, S. J.; Mehta, A.; Meier, K.; Mercer, D.; Merz, T.; Meyer, C. A.; Meyer, H.; Meyer, J.; Mikocki, S.; Milone, V.; Milstead, D.; Moreau, F.; Morris, J. V.; Müller, G.; Murín, P.; Nagovizin, V.; Naroska, B.; Naumann, Th.; Nawrath, G.; Newman, P. R.; Newton, D.; Neyret, D.; Nguyen, H. K.; Niebergall, F.; Niebuhr, C.; Nisius, R.; Nowak, G.; Noyes, G. W.; Nyberg-Werther, M.; Oberlack, H.; Obrock, U.; Olsson, J. E.; Panitch, A.; Pascaud, C.; Patel, G. D.; Peppel, E.; Perez, E.; Phillips, J. P.; Pichler, Ch.; Pitzl, D.; Pope, G.; Prell, S.; Prosi, R.; Rädel, G.; Raupach, F.; Reimer, P.; Reinshagen, S.; Ribarics, P.; Riech, V.; Riedlberger, J.; Riess, S.; Rietz, M.; Robertson, S. M.; Robmann, P.; Roosen, R.; Rosenbauer, K.; Rostovtsev, A.; Royon, C.; Rüter, K.; Ruffer, M.; Rusakov, S.; Rybicki, K.; Sahlmann, N.; Sanchez, E.; Sankey, D. P. C.; Savitsky, M.; Schacht, P.; Schleper, P.; von Schlippe, W.; Schmidt, C.; Schmidt, D.; Schöning, A.; Schröder, V.; Schulz, M.; Schwab, B.; Schwind, A.; Seehausen, U.; Sefkow, F.; Sell, R.; Semenov, A.; Shekelyan, V.; Sheviakov, I.; Shooshtari, H.; Shtarkov, L. N.; Siegmon, G.; Siewert, U.; Sirois, Y.; Skillicorn, I. O.; Smirnov, P.; Smith, J. R.; Soloviev, Y.; Spitzer, H.; Staroba, P.; Steenbock, M.; Steffen, P.; Steinberg, R.; Stella, B.; Stephens, K.; Stier, J.; Stiewe, J.; Stösslein, U.; Strachota, J.; Straumann, U.; Struczinski, W.; Sutton, J. P.; Tapprogge, S.; Taylor, R. E.; Tchernyshov, V.; Thiebaux, C.; Thompson, G.; Tichomirov, I.; Truöl, P.; Turnau, J.; Tutas, J.; Usik, A.; Valkar, S.; Valkarova, A.; Vallée, C.; Van Esch, P.; Van Mechelen, P.; Vartapetian, A.; Vazdik, Y.; Vecko, M.; Verrecchia, P.; Villet, G.; Wacker, K.

    1994-03-01

    The cross section of the charged current process e-p ? ve + hadrons is measured at HERA for transverse momenta of the hadron system larger than 25 GeV. The size of the cross section exhibits the W propagator.

  4. EXPLAINING DISCREPANCIES BETWEEN LONGITUDINAL AND CROSS-SECTIONAL MODELS

    EPA Science Inventory

    Discrepancies between estimates obtained from longitudinal studies analyzed cross-sectionally and longitudinally pose questions about the validity of cross-sectional estimates of change. n some cases these discrepancies are the result of period effects, cohort effects, or selecti...

  5. Radar Cross Section of Moving Objects

    E-print Network

    Gholizade, H

    2013-01-01

    I investigate the effects of movement on radar cross section calculations. The results show that relativistic effects (the constant velocity case) can change the RCS of moving targets by changing the incident plane wave field vectors. As in the Doppler effect, the changes in the fields are proportional to $\\frac{v}{c}$. For accelerated objects, using the Newtonian equations of motion yields an effective electric field (or effective current density) on the object due to the finite mass of the conducting electrons. The results indicate that the magnetic moment of an accelerated object is different from that of an un-accelerated object, and this difference can change the RCS of the object. Results for moving sphere and non-uniformly rotating sphere are given and compared with static (\\textbf{v}=0) case.

  6. ISSUES IN NEUTRON CROSS SECTION COVARIANCES

    SciTech Connect

    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.

  7. Lunar Radar Cross Section at Low Frequency

    NASA Technical Reports Server (NTRS)

    Rodriguez, P.; Kennedy, E. J.; Kossey, P.; McCarrick, M.; Kaiser, M. L.; Bougeret, J.-L.; Tokarev, Y. V.

    2002-01-01

    Recent bistatic measurements of the lunar radar cross-section have extended the spectrum to long radio wavelength. We have utilized the HF Active Auroral Research Program (HAARP) radar facility near Gakona, Alaska to transmit high power pulses at 8.075 MHz to the Moon; the echo pulses were received onboard the NASA/WIND spacecraft by the WAVES HF receiver. This lunar radar experiment follows our previous use of earth-based HF radar with satellites to conduct space experiments. The spacecraft was approaching the Moon for a scheduled orbit perturbation when our experiment of 13 September 2001 was conducted. During the two-hour experiment, the radial distance of the satellite from the Moon varied from 28 to 24 Rm, where Rm is in lunar radii.

  8. Cross section for charmonium absorption by nucleons 

    E-print Network

    Liu, W.; Ko, Che Ming; Lin, ZW.

    2002-01-01

    #, i.e., gpcDD*5gpDD*gcDD , grcDD52 grDDgcDD , grcD*D*5grD*D*gcD*D*. ~11! FIG. 1. J/C absorption by nucleon via pion and r meson ex- changes. 015203- The amplitudes for the first two processes in Fig. 1 are given by M 152igpNNN? ~p3!g5N~p1! 1... the method of Ref. @16# for the reaction NN?NLK , the spin and isospin averaged differential cross sections for the first two processes in Fig. 1 can be written as dsJ/cN?ND*D? dtds1 5 gpNN 2 16p2spi 2 kAs1~2t ! FpNN 2 ~ t ! ~ t2mp2 !2 3s...

  9. Electron Elastic-Scattering Cross-Section Database

    National Institute of Standards and Technology Data Gateway

    SRD 64 NIST Electron Elastic-Scattering Cross-Section Database (PC database, no charge)   This database provides values of differential elastic-scattering cross sections, corresponding total elastic-scattering cross sections, phase shifts, and transport cross sections for elements with atomic numbers from 1 to 96 and for electron energies between 50 eV and 20,000 eV (in steps of 1 eV).

  10. Modelling a geological cross-section: An experiment on uncertainty

    NASA Astrophysics Data System (ADS)

    Thorpe, Steve; Lark, Murray; Kessler, Holger; Mathers, Steve

    2015-04-01

    Uncertainty is becoming an important area of study within the geological modelling community. The methods to quantify and spatially describe uncertainty are complex and this experiment was designed to look at a narrow focus of uncertainty and try to provide some quantification. A designed experiment was conducted using a group of 28 geologists who modelled a cross-section in London, UK. Each geologist used interpreted borehole records which included three Palaeogene sedimentary units, including the target unit: the London Clay Formation. The boreholes were divided into batches from which validation boreholes had been withheld; as a result we obtained 129 point comparisons between the interpreted elevation of the base of the London Clay Formation and its observed elevation in a borehole not used for that particular interpretation. Analysis of the results showed good general agreement between the observed and interpreted elevations, with no evidence of systematic bias. Between-site variation of the interpretation error was spatially correlated, and the variance appeared to be stationary. The between-geologist component of variance was smaller overall, and depended on distance to the nearest borehole. There was also evidence that the between-geologist variance depends on the degree of experience of the individual. We used the statistical model of interpretation error to compute confidence intervals for any one interpretation of the base of the London Clay Formation in the cross-section, and to provide uncertainty measures for decision support in a hypothetical route-planning process. The statistical model could also be used to quantify error-propagation in a full 3D geological framework model calculated from the cross sections.

  11. Mental Visualization of Objects from Cross-Sectional Images

    ERIC Educational Resources Information Center

    Wu, Bing; Klatzky, Roberta L.; Stetten, George D.

    2012-01-01

    We extended the classic anorthoscopic viewing procedure to test a model of visualization of 3D structures from 2D cross-sections. Four experiments were conducted to examine key processes described in the model, localizing cross-sections within a common frame of reference and spatiotemporal integration of cross sections into a hierarchical object…

  12. Radar Cross Section Measurements of Frequency Selective Terahertz Retroreflectors

    E-print Network

    Massachusetts at Lowell, University of

    Radar Cross Section Measurements of Frequency Selective Terahertz Retroreflectors Richard J Laboratory, University of Massachusetts Lowell, Lowell, MA, USA 01854 ABSTRACT The radar cross section retroreflectors with diameters ranging from 2 mm to 8 mm were fabricated and their radar cross section

  13. Viscous Flow through Pipes of Various Cross-Sections

    ERIC Educational Resources Information Center

    Lekner, John

    2007-01-01

    An interesting variety of pipe cross-sectional shapes can be generated, for which the Navier-Stokes equations can be solved exactly. The simplest cases include the known solutions for elliptical and equilateral triangle cross-sections. Students can find pipe cross-sections from solutions of Laplace's equation in two dimensions, and then plot the…

  14. Prevalence and characteristics of tremor in the NARCOMS multiple sclerosis registry: a cross-sectional survey

    PubMed Central

    Rinker, John R; Salter, Amber R; Walker, Harrison; Amara, Amy; Meador, William; Cutter, Gary R

    2015-01-01

    Objectives (1)To describe the prevalence and severity of tremor in patients with multiple sclerosis (MS) registered within a large North American MS registry; (2) to provide detailed descriptions on the characteristics and severity of tremor in a subset of registrants and (3) to compare several measures of tremor severity for strength of agreement. Setting The North American Research Committee on MS (NARCOMS) registry. Participants Registrants of NARCOMS reporting mild or greater tremor severity. Outcome measures We determined the cross-sectional prevalence of tremor in the NARCOMS registry over three semiannual updates between fall 2010 and fall 2011. A subset of registrants (n=552) completed a supplemental survey providing detailed descriptions of their tremor. Outcomes included descriptive characteristics of their tremors and correlations between outcome measures to determine the strength of agreement in assessing tremor severity. Results The estimated prevalence of tremor in NARCOMS ranged from 45% to 46.8%, with severe tremor affecting 5.5–5.9% of respondents. In the subset completing the supplemental survey, mild tremor severity was associated with younger age of MS diagnosis and tremor onset than those with moderate or severe tremor. However, tremor severity did not differ by duration of disease or tremor. Respondents provided descriptions of tremor symptoms on the Clinical Ataxia Rating Scale, which had a moderate to good (?=0.595) correlation with the Tremor Related Activities of Daily Living (TRADL) scale. Objectively scored Archimedes’ spirals had a weaker (?=0.358) correlation with the TRADL. Rates of unemployment, disability and symptomatic medication use increased with tremor severity, but were high even among those with mild tremor. Conclusions Tremor is common among NARCOMS registrants and severely disabling for some. Both ADL-based and symptom-descriptive measures of tremor severity can be used to stratify patients. PMID:25573524

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

    SciTech Connect

    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 ..nu.., the average number of neutrons per fission, are also given.

  16. Abdominal sarcoidosis: cross-sectional imaging findings.

    PubMed

    Gezer, Naciye Sinem; Ba?ara, I??l; Altay, Canan; Harman, Mustafa; Rocher, Laurence; Karabulut, Nevzat; Seçil, Mustafa

    2015-01-01

    Sarcoidosis is a multisystem inflammatory disease of unknown etiology. The lungs and the lymphoid system are the most commonly involved organs. Extrapulmonary involvement is reported in 30% of patients, and the abdomen is the most common extrapulmonary site with a frequency of 50%-70%. Although intra-abdominal sarcoidosis is usually asymptomatic, its presence may affect the prognosis and treatment options. The lesions are less characteristic and may mimick neoplastic or infectious diseases such as lymphoma, diffuse metastasis, and granulomatous inflammation. The liver and spleen are the most common abdominal sites of involvement. Sarcoidosis of the gastrointestinal system, pancreas, and kidneys are extremely rare. Adenopathy which is most commonly found in the porta hepatis, exudative ascites, and multiple granulomatous nodules studding the peritoneum are the reported manifestations of abdominal sarcoidosis. Since abdominal sarcoidosis is less common and long-standing, unrecognized disease can result in significant morbidity and mortality. Imaging contributes to diagnosis and management of intra-abdominal sarcoidosis. In this report we reviewed the cross-sectional imaging findings of hepatobiliary, gastrointestinal, and genitourinary sarcoidosis. PMID:25512071

  17. Symmetry energy effects on fusion cross sections

    SciTech Connect

    Rizzo, C.; Di Toro, M.; Baran, V.; Colonna, M.; Corsi, A.

    2011-01-15

    We investigate the reaction path followed by heavy ion collisions with exotic nuclear beams at low energies. We focus on the interplay between reaction mechanisms, fusion vs. breakup (fast-fission, deep-inelastic), that in exotic systems is expected to be influenced by the symmetry energy term at densities around the normal value. The evolution of the system is described by a stochastic mean-field transport equation, where two parametrizations for the density dependence of symmetry energy (Asysoft and Asystiff) are implemented, allowing one to explore the sensitivity of the results to this ingredient of the nuclear interaction. The method described here, based on the event-by-event evolution of phase-space quadrupole collective modes, nicely allows us to extract the fusion probability at relatively early times, when the transport results are reliable. Fusion probabilities for reactions induced by {sup 132}Sn on {sup 64,58}Ni targets at 10 A MeV are evaluated. We obtain larger fusion cross sections for the more n-rich composite system, and, for a given reaction, in the Asysoft choice. Finally a collective charge equilibration mechanism (the dynamical dipole) is revealed in both fusion and breakup events, depending on the stiffnsess of the symmetry term just below saturation.

  18. Normalization of experimental electron cross sections.

    NASA Astrophysics Data System (ADS)

    Avdonina, N.; Felfli, Z.; Msezane, A. Z.

    1997-10-01

    Absolute experimental electron-impact differential cross sections (DCSs) can be obtained through an extrapolation of the relative generalized oscillator strength (GOS) values at some given impact energy E to zero momentum transfer squared K^2, the optical oscillator strength (OOS) [1]. We propose to normalize the relative experimental DCS data to the corresponding OOS value by extrapolating the GOS to K^2 = 0 without involving the nonphysical region. This is possible only by simultaneously increasing E and decreasing K^2 so that K^2 = 0 corresponds to E = ?. Thus is avoided a divergence of fracd(GOS)d(K^2) at K^2 = 0 [2]. Another advantage of our method is that, over a wide range of small K^2 values the contribution of higher order terms of the Born series to the GOS function is negligible, contrary to the constant E case in which even order K^2 terms are non-Born [2]. Thus first Born approximation can be used to normalize relative experimental DCSs to the OOS. This method is applicable to both the excitation and ionization of atomic and molecular targets by electron impact. The latter case generalizes the method of ref. [3]. ^*Supported by AFOSR, NSF and DoE Div. of Chemical Sciences, OBES. ^1 E. N. Lassettre et al., J. Chem. Phys \\underline50, (1829) ^2 W. M. Huo, J. Chem. Phys \\underline71, 1593 (1979) ^3 A. Saenz, W Weyrich and P. Froelich, J. Phys. B \\underline29, 97 (1996)

  19. [Fast neutron cross section measurements]. Progress report

    SciTech Connect

    Knoll, G.F.

    1992-10-26

    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.

  20. Abdominal sarcoidosis: cross-sectional imaging findings

    PubMed Central

    Gezer, Naciye Sinem; Ba?ara, I??l; Altay, Canan; Harman, Mustafa; Rocher, Laurence; Karabulut, Nevzat; Seçil, Mustafa

    2015-01-01

    Sarcoidosis is a multisystem inflammatory disease of unknown etiology. The lungs and the lymphoid system are the most commonly involved organs. Extrapulmonary involvement is reported in 30% of patients, and the abdomen is the most common extrapulmonary site with a frequency of 50%–70%. Although intra-abdominal sarcoidosis is usually asymptomatic, its presence may affect the prognosis and treatment options. The lesions are less characteristic and may mimick neoplastic or infectious diseases such as lymphoma, diffuse metastasis, and granulomatous inflammation. The liver and spleen are the most common abdominal sites of involvement. Sarcoidosis of the gastrointestinal system, pancreas, and kidneys are extremely rare. Adenopathy which is most commonly found in the porta hepatis, exudative ascites, and multiple granulomatous nodules studding the peritoneum are the reported manifestations of abdominal sarcoidosis. Since abdominal sarcoidosis is less common and long-standing, unrecognized disease can result in significant morbidity and mortality. Imaging contributes to diagnosis and management of intra-abdominal sarcoidosis. In this report we reviewed the cross-sectional imaging findings of hepatobiliary, gastrointestinal, and genitourinary sarcoidosis. PMID:25512071

  1. SCWR Once-Through Calculations for Transmutation and Cross Sections

    SciTech Connect

    ganda, francesco

    2012-07-01

    It is the purpose of this report to document the calculation of (1) the isotopic evolution and of (2) the 1-group cross sections as a function of burnup of the reference Super Critical Water Reactor (SCWR), in a format suitable for the Fuel Cycle Option Campaign Transmutation Data Library. The reference SCWR design was chosen to be that described in [McDonald, 2005]. Super Critical Water Reactors (SCWR) are intended to operate with super-critical water (i.e. H2O at a pressure above 22 MPa and a temperature above 373oC) as a cooling – and possibly also moderating – fluid. The main mission of the SCWR is to generate lower cost electricity, as compared to current standard Light Water Reactors (LWR). Because of the high operating pressure and temperature, SCWR feature a substantially higher thermal conversion efficiency than standard LWR – i.e. about 45% versus 33%, mostly due to an increase in the exit water temperature from ~300oC to ~500oC – potentially resulting in a lower cost of generated electricity. The coolant remains single phase throughout the reactor and the energy conversion system, thus eliminating the need for pressurizers, steam generators, steam separators and dryers, further potentially reducing the reactor construction capital cost. The SCWR concept presented here is based on existing LWR technology and on a large number of existing fossil-fired supercritical boilers. However, it was concluded in [McDonald, 2005], that: “Based on the results of this study, it appears that the reference SCWR design is not feasible.” This conclusion appears based on the strong sensitivity of the design to small deviations in nominal conditions leading to small effects having a potentially large impact on the peak cladding temperature of some fuel rods. “This was considered a major feasibility issue for the SCWR” [McDonald, 2005]. After a description of the reference SCWR design, the Keno V 3-D single assembly model used for this analysis, as well as the calculated results, are presented. Additionally, the follwing information, presented in the appendixes, is intended to provide enough guidance that a researcher repeating the same task in the future should be able to obtain a vector of nuclei and cross sections ready for insertion into the transmutation library without any need for further instructions: (1) Complete TRITON/KENO-V input used for the analysis; (2) Inputs and detailed description of the usage of the OPUS utility, used to postproces and to extract the nuclei concentrations for the transmutation library; (3) Inputs and detailed description of the usage of the XSECLIST utility, used to postproces and to extract the 1-group cross sections for the transmutation library; (4) Details of an ad-hoc utility program developed to sort the nuclei and cross sections for the transmutation library.

  2. Parabolic versus spherical partial cross sections for photoionization excitation of He near threshold

    SciTech Connect

    Bouri, C.; Selles, P.; Malegat, L.; Kwato Njock, M. G.

    2006-09-15

    Spherical and parabolic partial cross sections and asymmetry parameters, defined in the ejected electron frame, are presented for photoionization excitation of the helium atom at 0.1 eV above its double ionization threshold. A quantitative law giving the dominant spherical partial wave l{sub dom} for each excitation level n is obtained. The parabolic partial cross sections are shown to satisfy the same approximate selection rules as the related Rydberg series of doubly excited states (K,T){sub n}{sup A}. The analysis of radial and angular correlations reveals the close relationship between double excitation, ionization excitation, and double ionization. Opposite to a widespread belief, the observed value of the asymmetry parameter is shown to result from the interplay of radial correlations and symmetry constraints, irrespective of angular correlations. Finally, the measurement of parabolic partial cross sections is proposed as a challenge to experimentalists.

  3. Hafnium neutron cross sections and resonance analysis

    NASA Astrophysics Data System (ADS)

    Trbovich, Michael J.

    The focus of this thesis is to determine resonance parameters for the stable hafnium isotopes in the 0.005--200 eV region, with emphasis on the overlapping 176Hf and 178Hf resonances near 8 eV. The large neutron cross section of hafnium, combined with its corrosion resistance and excellent mechanical properties, make it an ideal material for controlling nuclear reactions. Experiments measuring neutron capture and transmission were performed at the Rensselaer Polytechnic Institute (RPI) LINAC using the time of flight method. Transmission experiments utilized 6Li glass scintillation detectors at flight path lengths of 15 and 25 m. Capture experiments were done using a sixteen section NaI(Tl) multiplicity type detector at a flight path length of 25 m. These experiments utilized various thicknesses of metallic and isotope-enriched liquid samples. The liquid samples were designed to provide information on the 176Hf and 178Hf contributions to the 8 eV doublet without saturation. Data analysis was done using the R-matrix Bayesian fitting code SAMMY version M6 beta. SAMMY is able to account for experimental resolution effects for each of the experimental setups at the RPI LINAC, and also can correct for some of the multiple scattering effects in yield data. The resolution function for specific experimental setups was determined. A method was developed for estimating errors on the fitted resonance parameters due to uncertainties in the resolution function parameters. The combined capture and transmission data analysis yielded resonance parameters for all stable hafnium isotopes from 0.005--200 eV. Resonance integrals were calculated along with errors for each of the hafnium isotopes using the NJOY and INTER codes. The isotopic resonance integrals calculated were significantly different than some of the previous values; however the calculated elemental hafnium resonance integral changed very little.

  4. Neutron Cross Section Uncertainties in the Thermal and Resonance Regions

    SciTech Connect

    Mughabghab,S.F.; Oblozinsky, P.

    2008-06-24

    In the 'Atlas of Neutron Resonances', special care was expended to ensure that the resonance parameter information reproduces the various measured thermal cross sections, as well as the infinite dilute resonance integrals for Z = 1-100. In contrast, the uncertainties of the recommended quantities do not match those generated from the uncertainties of the resonance parameters. To address this problem, the present study was initiated to achieve consistency for 15 actinides and 21 structural and coolant moderator materials. This is realized by assigning uncertainties to the parameters of the negative-energy resonances and changing, if necessary, significantly the uncertainties of the low-lying positive-energy resonances. The influence of correlations between parameters on the derived uncertainties is examined and discussed.

  5. Electron microscopy shows periodic structure in collagen fibril cross sections.

    PubMed Central

    Hulmes, D J; Jesior, J C; Miller, A; Berthet-Colominas, C; Wolff, C

    1981-01-01

    X-ray diffraction was used to monitor the effects of electron microscope fixation, staining, and embedding procedures on the preservation of the three-dimensional crystalline order in collagen fibrils of rat tail tendon. A procedure is described in which the characteristic 3.8-nm lateral spacing is preserved, with increased contrast, in the diffraction pattern of the embedded fiber. This spacing is correlated with the separation between the tangentially oriented equally spaced lines of density observed in electron microscope ultrathin fibril cross sections of the same material. Optical diffraction of electron micrographs gives an objective measure of the periodicity and suggests that the fibril is composed of concentrically oriented crystalline domains. These observations, when combined with a recent interpretation of the native x-ray diffraction data [Hulmes, D. J. S. & Miller, A. (1979) Nature (London) 282, 878-880] suggest a tentative model for the three-dimensional structure of collagen fibrils. Images PMID:6943556

  6. Measurement of spin dependent total cross sections in neutron-deuteron scattering

    SciTech Connect

    Klouzal, J.; Dolezal, Z.; Ivanov, M. I.; Kodys, P.; Tsvetkov, A.I.; Wilhelm, I.; Borisov, N.S.; Kuzmin, E.S.; Plis, Yu.A.; Usov, Yu.A.; Gurevich, G. M.; Lukhanin, A.A.

    2005-05-06

    The measurement of longitudinal and transversal asymmetries {delta}{sigma}L and {delta}{sigma}T of spin dependent neutron-deuteron total cross section at En = 16 MeV is taking place in VdG accelerator laboratory at Charles University, Prague. Theoretical predictions and description of detection apparatus are presented in this paper.

  7. Calculation of the cross section for charge transfer in fullerene-fullerene collisions

    SciTech Connect

    Iroshnikov, G. S.

    2006-11-15

    An expression for the charge transfer cross section in fullerene-fullerene collisions is derived by using an instanton approximation for the tunnel splitting of energy levels. The expression is valid in the adiabatic approximation and provides an accurate description of available experimental data.

  8. ION — a program to evaluate cross-sections for ionisation in ion-atom collisions

    NASA Astrophysics Data System (ADS)

    Crothers, D. S. F.; McCartney, M.

    1992-11-01

    A program is presented which calculates total and differential cross-sections for the ionisation of hydrogen-like targets by the impact of fully stripped ions. Any one of four theoretical descriptions can be used, namely, (i) the first Born approximation, (ii) the distorted wave born approximation, (iii) the continuum distorted wave approximation, or (iv) the continuum distorted wave eikonal initial state approximation.

  9. Argon plasma modeling with detailed fine-structure cross sections

    SciTech Connect

    Gangwar, R. K.; Sharma, L.; Srivastava, R.; Stauffer, A. D.

    2012-03-01

    Our recently reported fully relativistic distorted-wave electron-impact cross sections from the ground and metastable states of argon to various excited fine-structure levels are incorporated in a collisional-radiative model to obtain the population densities for the 3p{sup 5}4s and 3p{sup 5}4p (1s and 2p) fine-structure manifolds for low temperature argon plasmas. Excitation cross sections from the two 3p{sup 5}4s J = 1 resonance levels, 1s{sub 2} and 1s{sub 4}, to the higher lying 2p fine-structure manifold as well as for transitions among individual levels of the 1s and 2p manifolds are also calculated and included in the present model which were not fully considered in any earlier model. Our results for the population densities of the 1s and 2p levels show good agreement with recent measurements. The variation of population densities of all the 1s and 2p levels with electron temperature and density are presented. We have also calculated and compared the intensities for the 750.38 nm (2p{sub 1}{yields} 1s{sub 2}) and 696.54 nm (2p{sub 2}{yields} 1s{sub 5}) lines with recently reported experimental results. The present work suggests that the inclusion of a complete fine-structure description of the electronic processes occurring in the plasma is important for a collisional radiative model, which includes separate 1s and 2p levels.

  10. Measured microwave scattering cross sections of three meteorite specimens

    NASA Technical Reports Server (NTRS)

    Hughes, W. E.

    1972-01-01

    Three meteorite specimens were used in a microwave scattering experiment to determine the scattering cross sections of stony meteorites and iron meteorites in the frequency range from 10 to 14 GHz. The results indicate that the stony meteorites have a microwave scattering cross section that is 30 to 50 percent of their projected optical cross section. Measurements of the iron meteorite scattering were inconclusive because of specimen surface irregularities.

  11. Projectile and Lab Frame Differential Cross Sections for Electromagnetic Dissociation

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Adamczyk, Anne; Dick, Frank

    2008-01-01

    Differential cross sections for electromagnetic dissociation in nuclear collisions are calculated for the first time. In order to be useful for three - dimensional transport codes, these cross sections have been calculated in both the projectile and lab frames. The formulas for these cross sections are such that they can be immediately used in space radiation transport codes. Only a limited amount of data exists, but the comparison between theory and experiment is good.

  12. Neutrino-Nucleon Cross section in Ultra High Energy Regime

    E-print Network

    Bora, Kalpana

    2015-01-01

    Neutrino Physics is now entering precision era and neutrino-nucleon cross sections are an im- portant ingredient in all neutrino oscillation experiments. Specially, precise knowledge of neutrino- nucleon cross sections in Ultra High Energy (UHE) regime (TeV-PeV) is becoming more important now, as several experiments worldwide are going to observe processes involving such UHE neutrinos. In this work, we present new results on neutrino-nucleon cross-sections in this UHE regime, using QCD.

  13. Neutrino-Nucleon Cross section in Ultra High Energy Regime

    E-print Network

    Kalpana Bora; Neelakshi Sarma

    2015-11-09

    Neutrino Physics is now entering precision era and neutrino-nucleon cross sections are an im- portant ingredient in all neutrino oscillation experiments. Specially, precise knowledge of neutrino- nucleon cross sections in Ultra High Energy (UHE) regime (TeV-PeV) is becoming more important now, as several experiments worldwide are going to observe processes involving such UHE neutrinos. In this work, we present new results on neutrino-nucleon cross-sections in this UHE regime, using QCD.

  14. High E{sub T} jet cross sections at CDF

    SciTech Connect

    Flaugher, B.; CDF Collaboration

    1996-08-01

    The inclusive jet cross section for {ital p}{ital {anti p}} collisions at {radical}s = 1.8 TeV as measured by the CDF collaboration will be presented. Preliminary CDF measurements of the {Sigma} E{sub T} cross section at {radical}s = 1.8 TeV and the central inclusive jet cross section at {radical}s = 0.630 TeV will also be shown.

  15. Proton-Air Cross Section and Extensive Air Showers

    E-print Network

    Ralf Ulrich; Ralph Engel; Steffen Müller; Fabian Schüssler; Michael Unger

    2009-06-17

    Hadronic cross sections at ultra-high energy have a significant impact on the development of extensive air shower cascades. Therefore the interpretation of air shower data depends critically on hadronic interaction models that extrapolate the cross section from accelerator measurements to the highest cosmic ray energies. We discuss how extreme scenarios of cross section extrapolations can affect the interpretation of air shower data. We find that the theoretical uncertainty of the extrapolated proton-air cross section at ultra-high energies is much larger than suggested by the existing spread of available Monte Carlo model predictions. The impact on the depth of the shower maximum is demonstrated.

  16. Neutron-capture Cross Sections from Indirect Measurements

    SciTech Connect

    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.

  17. Positive Scattering Cross Sections using Constrained Least Squares

    SciTech Connect

    Dahl, J.A.; Ganapol, B.D.; Morel, J.E.

    1999-09-27

    A method which creates a positive Legendre expansion from truncated Legendre cross section libraries is presented. The cross section moments of order two and greater are modified by a constrained least squares algorithm, subject to the constraints that the zeroth and first moments remain constant, and that the standard discrete ordinate scattering matrix is positive. A method using the maximum entropy representation of the cross section which reduces the error of these modified moments is also presented. These methods are implemented in PARTISN, and numerical results from a transport calculation using highly anisotropic scattering cross sections with the exponential discontinuous spatial scheme is presented.

  18. Partial photoneutron cross sections for the isomeric state 180Tam.

    PubMed

    Goko, S; Utsunomiya, H; Goriely, S; Makinaga, A; Kaihori, T; Hohara, S; Akimune, H; Yamagata, T; Lui, Y-W; Toyokawa, H; Koning, A J; Hilaire, S

    2006-05-19

    Photoneutron cross sections for (181)Ta(y, n) (180)Ta(m) were determined from simultaneous measurements of total cross sections (sigma(tot) and ground-state cross sections (sigma(gs)) for (180)Ta in photodisintegration of with laser Compton-backscattered rays. Techniques of direct neutron counting and photoactivation were used for the measurement of sigma(tot) and sigma(gs), respectively. The partial cross sections for the isomeric state serves as a novel probe of the nuclear level density of (180)Ta. Implications for the p- and s-process nucleosynthesis of (180)Ta(m) are given. PMID:16803099

  19. Report on 241,242Am(n,x) surrogate cross section measurement

    SciTech Connect

    Burke, J T; Ressler, J J; Gostic, J; Henderson, R A; Bernstein, L A; Escher, J E; Bleuel, D; Kritcher, A; Matoon, C; Scielzo, N D; Stoyer, M A

    2011-02-16

    The main goal of this measurement is to determine the {sup 242}Am(n,f) and {sup 241}Am(n,f) cross sections via the surrogate {sup 243}Am. Gamma-ray data was also collected for the purpose of measuring the (n,2n) cross-sections. The experiment was conducted using the STARS/LIBERACE experimental facility located at the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory the first week of February 2011. A description of the experiment and status of the data analysis follow.

  20. Isotopic dependence of the cross section for the induced fission of heavy nuclei

    SciTech Connect

    Bolgova, O. N.; Adamian, G. G.; Antonenko, N. V.; Zubov, A. S.; Ivanova, S. P.; Scheid, W.

    2009-06-15

    The cross sections for the induced fission of {sup 211-223}Ra, {sup 203-211}Rn, and {sup 221-231}Th nuclei undergoing peripheral collisions with {sup 208}Pb nuclei are calculated on the basis of the statistical model. The role of the N = 126 neutron shell is studied. The level density in excited nuclei is determined within the Fermi gas model and a model that takes into account the collective enhancement of the level density. The inclusion of a particle-hole excitation in addition to a collective Coulomb excitation makes it possible to obtain a satisfactory description of experimental cross sections for the fission of radium isotopes. The calculated ratios of the cross sections for the induced fission of {sup 236}U ({sup 237}U) and {sup 238}U ({sup 239}U) nuclei agree with experimental data.

  1. Cross Sections for Inner-Shell Ionization by Electron Impact

    SciTech Connect

    Llovet, Xavier; Powell, Cedric J.; Salvat, Francesc; Jablonski, Aleksander

    2014-03-15

    An analysis is presented of measured and calculated cross sections for inner-shell ionization by electron impact. We describe the essentials of classical and semiclassical models and of quantum approximations for computing ionization cross sections. The emphasis is on the recent formulation of the distorted-wave Born approximation by Bote and Salvat [Phys. Rev. A 77, 042701 (2008)] that has been used to generate an extensive database of cross sections for the ionization of the K shell and the L and M subshells of all elements from hydrogen to einsteinium (Z = 1 to Z = 99) by electrons and positrons with kinetic energies up to 1 GeV. We describe a systematic method for evaluating cross sections for emission of x rays and Auger electrons based on atomic transition probabilities from the Evaluated Atomic Data Library of Perkins et al. [Lawrence Livermore National Laboratory, UCRL-ID-50400, 1991]. We made an extensive comparison of measured K-shell, L-subshell, and M-subshell ionization cross sections and of L? x-ray production cross sections with the corresponding calculated cross sections. We identified elements for which there were at least three (for K shells) or two (for L and M subshells) mutually consistent sets of cross-section measurements and for which the cross sections varied with energy as expected by theory. The overall average root-mean-square deviation between the measured and calculated cross sections was 10.9% and the overall average deviation was ?2.5%. This degree of agreement between measured and calculated ionization and x-ray production cross sections was considered to be very satisfactory given the difficulties of these measurements.

  2. In-medium nucleon-nucleon elastic cross sections determined from nucleon-induced reaction cross sections data

    E-print Network

    Li Ou

    2015-09-10

    Within the framework of the improved quantum molecular dynamics model, the medium modifications on the free nucleon-nucleon elastic cross sections are investigated. By using various in-medium nucleon-nucleon elastic cross sections in the model, the nucleon-induced reactions on various targets are simulated, and the excitation functions of reaction cross sections in the energy range from 25 MeV to 1 GeV are calculated. By comparing the calculations with the experimental data, an isospin, density, and momentum-dependence medium correction factor on free nucleon-nucleon elastic cross sections is determined.

  3. Total cross sections for positrons scattered elastically from helium based on new measurements of total ionization cross sections

    NASA Technical Reports Server (NTRS)

    Diana, L. M.; Chaplin, R. L.; Brooks, D. L.; Adams, J. T.; Reyna, L. K.

    1990-01-01

    An improved technique is presented for employing the 2.3m spectrometer to measure total ionization cross sections, Q sub ion, for positrons incident on He. The new ionization cross section agree with the values reported earlier. Estimates are also presented of total elastic scattering cross section, Q sub el, obtained by subtracting from total scattering cross sections, Q sub tot, reported in the literature, the Q sub ion and Q sub Ps (total positronium formation cross sections) and total excitation cross sections, Q sub ex, published by another researcher. The Q sub ion and Q sub el measured with the 3m high resolution time-of-flight spectrometer for 54.9eV positrons are in accord with the results from the 2.3m spectrometer. The ionization cross sections are in fair agreement with theory tending for the most part to be higher, especially at 76.3 and 88.5eV. The elastic cross section agree quite well with theory to the vicinity of 50eV, but at 60eV and above the experimental elastic cross sections climb to and remain at about 0.30 pi a sub o sq while the theoretical values steadily decrease.

  4. The High-Energy Behavior of Photon, Neutrino and Proton Cross Sections

    E-print Network

    Carlos A. Arguelles; Francis Halzen; Logan Wille; Mike Kroll; Mary Hall Reno

    2015-04-29

    By combining the color dipole model of the nucleon with the assumption that cross sections behave asymptotically as $\\ln^2(s)$, we are able to describe the data for photon, neutrino and hadron interactions with protons at all energies, $s$ is the center-of-mass energy of the interacting particles. Specifically, we extrapolate the perturbative QCD calculations into the regime of small fractional parton momenta $x$ using a color dipole description of the proton target that guarantees an asymptotic $\\ln^2(s)$ behavior of all cross sections. The ambiguity of introducing a parametrization associated with the dipole approximation is mitigated by the requirement that the saturation of the small-$x$ structure functions produces $\\ln^2(s)$-behaved asymptotic cross sections, in agreement with the data. The same formalism allows us to calculate the cross section for the hadronic pair production of charm particles. The results, in particular those for the high-energy neutrino and charm cross sections, are relevant for evaluating the sensitivity as well as the background in neutrino telescopes.

  5. Determination of the Ce142(?,n) cross section using quasi-monoenergetic Compton backscattered ? rays

    NASA Astrophysics Data System (ADS)

    Sauerwein, A.; Sonnabend, K.; Fritzsche, M.; Glorius, J.; Kwan, E.; Pietralla, N.; Romig, C.; Rusev, G.; Savran, D.; Schnorrenberger, L.; Tonchev, A. P.; Tornow, W.; Weller, H. R.

    2014-03-01

    Background: Knowing the energy dependence of the (?,n) cross section is mandatory to predict the abundances of heavy elements using astrophysical models. The data can be applied directly or used to constrain the cross section of the inverse (n,?) reaction. Purpose: The measurement of the reaction Ce142(?,n)141Ce just above the reaction threshold amends the existing experimental database in that mass region for p-process nucleosynthesis and helps to understand the s-process branching at the isotope Ce141. Method: The quasi-monoenergetic photon beam of the High Intensity ?-ray Source (HI?S), TUNL, USA, is used to irradiate naturally composed Ce targets. The reaction yield is determined afterwards with high-resolution ?-ray spectroscopy. Results: The experimental data are in agreement with previous measurements at higher energies. Since the cross-section prediction of the Ce142(?,n) reaction is exclusively sensitive to the ?-ray strength function, the resulting cross-section values were compared to Hauser-Feshbach calculations using different ?-ray strength functions. A microscopic description within the framework of the Hartree-Fock-BCS model describes the experimental values well within the measured energy range. Conclusions: The measured data show that the predicted (?,n) reaction rate is correct within a factor of 2 even though the closed neutron shell N =82 is approached. This agreement allows us to constrain the (n,?) cross section and to improve the understanding of the s-process branching at Ce141.

  6. Neutron cross section evaluations for actinides at intermediate energies sup 2 sup 3 sup 9 Pu

    E-print Network

    Ignatyuk, A V; Gudowski, W; Lunev, V P; Shubin, Yu N; Titarenko, N N

    2001-01-01

    Investigations aimed at the development of neutron cross section evaluations for actinides performed at IPPE in collaboration with Royal Institute of Technology, Stockholm at intermediate energies in the range of 0-200 MeV are briefly described on the example of sup 2 sup 3 sup 9 Pu. The coupled-channels optical model is used to calculate the neutron total, elastic and reaction cross sections and the elastic scattering angular distributions. Evaluations of the neutron and charged particle emission cross sections and of the fission cross sections are obtained on the basis of the statistical description that includes direct, preequilibrium and equilibrium mechanisms of nuclear reactions. The Kalbach parametrization of angular distributions is used to describe the double-differential cross sections of emitted neutrons and charged particles in ENDF/B-VI format. These investigations resulted in creation of complete neutron and proton data files for sup 2 sup 3 sup 8 U and sup 2 sup 3 sup 2 Th and neutron data file...

  7. Cross-section measurement of the $^{130}$Ba(p,$?$)$^{131}$La reaction for $?$-process nucleosynthesis

    E-print Network

    L. Netterdon; A. Endres; G. G. Kiss; J. Mayer; T. Rauscher; P. Scholz; K. Sonnabend; Zs. Török; A. Zilges

    2014-09-27

    A measurement of total cross-section values of the $^{130}$Ba(p,$\\gamma$)$^{131}$La reaction at low proton energies allows a stringent test of statistical model predictions with different proton+nucleus optical model potentials. Since no experimental data are available for proton-capture reactions in this mass region around A~$\\approx$~130, this measurement can be an important input to test the global applicability of proton+nucleus optical model potentials. The total reaction cross-section values were measured by means of the activation method. After the irradiation with protons, the reaction yield was determined by use of $\\gamma$-ray spectroscopy using two clover-type high-purity germanium detectors. In total, cross-section values for eight different proton energies could be determined in the energy range between 3.6 MeV $\\leq E_p \\leq$ 5.0 MeV, thus, inside the astrophysically relevant energy region. The measured cross-section values were compared to Hauser-Feshbach calculations using the statistical model codes TALYS and SMARAGD with different proton+nucleus optical model potentials. With the semi-microscopic JLM proton+nucleus optical model potential used in the SMARAGD code, the absolute cross-section values are reproduced well, but the energy dependence is too steep at the lowest energies. The best description is given by a TALYS calculation using the semi-microscopic Bauge proton+nucleus optical model potential using a constant renormalization factor.

  8. Prevalence and correlates of HIV, syphilis, and hepatitis B and C infection and harm reduction program use among male injecting drug users in Kabul, Afghanistan: A cross-sectional assessment

    PubMed Central

    2011-01-01

    Background A nascent HIV epidemic and high prevalence of risky drug practices were detected among injecting drug users (IDUs) in Kabul, Afghanistan from 2005-2006. We assessed prevalence of HIV, hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg), syphilis, and needle and syringe program (NSP) use among this population. Methods IDUs were recruited between June, 2007 and March, 2009 and completed questionnaires and rapid testing for HIV, HCV, HBsAg, and syphilis; positive samples received confirmatory testing. Logistic regression was used to identify correlates of HIV, HCV, and current NSP use. Results Of 483 participants, all were male and median age, age at first injection, and duration of injection were 28, 24, and 2.0 years, respectively. One-fifth (23.0%) had initiated injecting within the last year. Reported risky injecting practices included ever sharing needles/syringes (16.9%) or other injecting equipment (38.4%). Prevalence of HIV, HCV Ab, HBSAg, and syphilis was 2.1% (95% CI: 1.0-3.8), 36.1% (95% CI: 31.8-40.4), 4.6% (95% CI: 2.9-6.9), and 1.2% (95% CI: 0.5-2.7), respectively. HIV and HCV infection were both independently associated with sharing needles/syringes (AOR = 5.96, 95% CI: 1.58 - 22.38 and AOR = 2.33, 95% CI: 1.38 - 3.95, respectively). Approximately half (53.8%) of the participants were using NSP services at time of enrollment and 51.3% reported receiving syringes from NSPs in the last three months. Current NSP use was associated with initiating drug use with injecting (AOR = 2.58, 95% CI: 1.22 - 5.44), sharing injecting equipment in the last three months (AOR = 1.79, 95% CI: 1.16 - 2.77), prior incarceration (AOR = 1.57, 95% CI: 1.06 - 2.32), and greater daily frequency of injecting (AOR = 1.40 injections daily, 95% CI: 1.08 - 1.82). Conclusions HIV and HCV prevalence appear stable among Kabul IDUs, though the substantial number having recently initiated injecting raises concern that transmission risk may increase over time. Harm reduction programming appears to be reaching high-risk drug user populations; however, monitoring is warranted to determine efficacy of prevention programming in this dynamic environment. PMID:21867518

  9. Application of cross-sectional time series modeling for the prediction of energy expenditure from heart rate and accelerometry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate estimation of energy expenditure (EE) in children and adolescents is required for a better understanding of physiological, behavioral, and environmental factors affecting energy balance. Cross-sectional time series (CSTS) models, which account for correlation structure of repeated observati...

  10. D0 papers on B-physics submitted to DPF '96: b-quark inclusive cross sections and b anti-b correlations using dimuons from the D0 experiment; Single muon production in the forward region at [radical]s=1. 8 TEV; Rapidity dependence of the inclusive J[psi] production in the forward region [radical]s=1. 8 TEV; A search for b [r arrow] X[mu][sup +][mu][sup [minus

    SciTech Connect

    Vititoe, D.L. . Dept. of Physics); Kozelov, Alexander; Jesik, Richard; D0 Collaboration.

    1996-11-01

    Paper 1: Using dimuons collected with the D0 detector during the 1993--1995 Tevatron collider run, the authors have measured the b-quark cross section and b[anti b] correlations as given by the difference in azimuthal angle between the two muons. Both measurements agree with the NLO QCD predictions within experimental and theoretical errors. (Three other papers are included in this report.)

  11. Emission Cross Sections for Neutral Xenon Impacted by Xe+

    E-print Network

    King, Lyon B.

    Emission Cross Sections for Neutral Xenon Impacted by Xe+ and Xe2+ by Jason D. Sommerville A Thesis Emission cross sections for Neutral Xenon Impacted by Xe+ and Xe2+ by Jason D. Sommerville is hereby for eleven transitions from the 5p5 6p configuration to the 5p5 6s configuration of neutral xenon occur- ring

  12. LORENTZ SYMMETRY VIOLATION AND VERY HIGHENERGY CROSS SECTIONS

    E-print Network

    LORENTZ SYMMETRY VIOLATION AND VERY HIGH­ENERGY CROSS SECTIONS Luis GONZALEZ­MESTRES 1 Laboratoire­le­Vieux Cedex, France Abstract We discuss the implications of a recently proposed pattern of Lorentz symmetry violation on very high­energy cross sections. As a consequence of the breaking of local Lorentz invariance

  13. Neutron capture cross sections: from theory to experiments and back

    E-print Network

    Alberto Mengoni

    2005-01-31

    The method for an experimental determination of the stellar enhancement factor for the cross section of the $^{151}$Sm$(n,\\gamma)$ reaction process is proposed. This study offered the pretext for an excursus on the interconnections between capture and dissociation reactions and the interplay between theory and experiments in the determination of neutron capture cross sections.

  14. Electromgnetic-gravitational cross-sections in external elctromagnetic fields

    E-print Network

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

    1994-10-03

    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 condesor and the magnetic field of the selenoid. A numerical evaluation shows that the cross sections may have the observable value in the present technical scenario.

  15. Analysis of cross sections using various nuclear potential

    SciTech Connect

    Aziz, Azni Abdul; Kassim, Hasan Abu; Yusof, Norhasliza; Muhammad Zamrun, F.

    2014-05-02

    The relevant astrophysical reaction rates which are derived from the reaction cross sections are necessary input to the reaction network. In this work, we analyse several theoretical models of the nuclear potential which give better prediction of the cross sections for some selected reactions.

  16. Learning of Cross-Sectional Anatomy Using Clay Models

    ERIC Educational Resources Information Center

    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…

  17. Cross section dependence of event rates at neutrino telescopes

    E-print Network

    Marfatia, Danny; Seckel, D.; McKay, D. W.; Hussain, S.

    2006-10-20

    We examine the dependence of event rates at neutrino telescopes on the neutrino-nucleon cross section for neutrinos with energy above 1 PeV, and contrast the results with those for cosmic ray experiments. Scaling of the standard model cross sections...

  18. Thermal neutron-induced fission cross sections of Cm isotopes

    NASA Astrophysics Data System (ADS)

    Popescu, L.; Heyse, J.; Wagemans, J.; Wagemans, C.

    2009-10-01

    A new measurement program was set up at SCK?CEN to determine the thermal neutron-induced fission cross section of a number of Cm isotopes. These transuranium isotopes are produced in nuclear reactors and are candidates for transmutation. This paper presents preliminary results of our 245Cm(n,f) cross-section measurement.

  19. Fig. 1: Cross-section of experimental combustor and instrumentation

    E-print Network

    Hallett, William L.H.

    Fig. 1: Cross-section of experimental combustor and instrumentation Fig. 2: Cross-section of tip vertically upwards(Fig. 1). Fresh fuel is fed tothe surface to keep the level constant; devolatilization to avoid condensing tar in the probe. A novel probe was therefore designed (Fig. 2), which condenses

  20. Cross sections for track structure codes: volume versus surface transport.

    PubMed

    Dingfelder, M; Travia, A

    2015-09-01

    Cross-section calculations and transport models for Monte Carlo track structure codes are discussed as well as the simulation of secondary electron emission yields from thin metal foils. Inelastic cross sections for volume (bulk) and surface transport of electrons in copper are presented and implemented into PARTRAC. Simulations for the volume and surface excitation model are presented and analysed. PMID:25953789

  1. Random Phase Approximation and neutrino-nucleus cross sections

    E-print Network

    Giampaolo Co'

    2006-05-22

    The Random Phase Approximation theory is used to calculate the total cross sections of electron neutrinos on $^{12}$C nucleus. The role of the excitation of the discrete spectrum is discussed. A comparison with electron scattering and muon capture data is presented. The cross section of electron neutrinos coming from muon decay at rest is calculated.

  2. Author's Accepted Manuscript Rayleigh scattering cross-section measure-

    E-print Network

    Author's Accepted Manuscript Rayleigh scattering cross-section measure- ments of nitrogen, argon Volkamer, Rayleigh scattering cross-section measurements of nitrogen, argon, oxygen and air, Journal crosssection measurements of nitrogen, argon, oxygen and air Ryan Thalmana,b, * , Kyle J. Zarzanaa

  3. Molecular Structures and Ion Mobility Cross Sections: Analysis of the Effects of He and N2 Buffer Gas.

    PubMed

    Bleiholder, Christian; Johnson, Nicholas R; Contreras, Stephanie; Wyttenbach, Thomas; Bowers, Michael T

    2015-07-21

    An empirically observed correlation between ion mobility cross sections in helium and nitrogen buffer gases was examined as a function of temperature, molecular size, and shape. Experimental cross sections were determined for tetraglycine, bradykinin, angiotensin 2, melittin, and ubiquitin at 300 K and in the range from 80 to 550 K on home-built instruments and calculated by the projection superposition approximation (PSA) method. The PSA was also used to predict cross sections for larger systems such as human pancreatic alpha-amylase, concanavalin, Pichia pastoris lysyl oxidase, and Klebsiella pneumoniae acetolactate synthase. The data show that the ratio of cross sections in helium and nitrogen depends significantly on the temperature of the buffer gas as well as the size and shape of the analyte ion. Therefore, the analysis of the data indicates that a simple formula that seeks to quantitatively relate the momentum transfer cross sections observed in two distinct buffer gases lacks a sound physical basis. PMID:26076363

  4. AFCI-2.0 Neutron Cross Section Covariance Library

    SciTech Connect

    Herman, M.; Herman, M; Oblozinsky, P.; Mattoon, C.M.; Pigni, M.; Hoblit, S.; Mughabghab, S.F.; Sonzogni, A.; Talou, P.; Chadwick, M.B.; Hale, G.M.; Kahler, A.C.; Kawano, T.; Little, R.C.; Yount, P.G.

    2011-03-01

    The cross section covariance library has been under development by BNL-LANL collaborative effort over the last three years. The project builds on two covariance libraries developed earlier, with considerable input from BNL and LANL. In 2006, international effort under WPEC Subgroup 26 produced BOLNA covariance library by putting together data, often preliminary, from various sources for most important materials for nuclear reactor technology. This was followed in 2007 by collaborative effort of four US national laboratories to produce covariances, often of modest quality - hence the name low-fidelity, for virtually complete set of materials included in ENDF/B-VII.0. The present project is focusing on covariances of 4-5 major reaction channels for 110 materials of importance for power reactors. The work started under Global Nuclear Energy Partnership (GNEP) in 2008, which changed to Advanced Fuel Cycle Initiative (AFCI) in 2009. With the 2011 release the name has changed to the Covariance Multigroup Matrix for Advanced Reactor Applications (COMMARA) version 2.0. The primary purpose of the library is to provide covariances for AFCI data adjustment project, which is focusing on the needs of fast advanced burner reactors. Responsibility of BNL was defined as developing covariances for structural materials and fission products, management of the library and coordination of the work; LANL responsibility was defined as covariances for light nuclei and actinides. The COMMARA-2.0 covariance library has been developed by BNL-LANL collaboration for Advanced Fuel Cycle Initiative applications over the period of three years, 2008-2010. It contains covariances for 110 materials relevant to fast reactor R&D. The library is to be used together with the ENDF/B-VII.0 central values of the latest official release of US files of evaluated neutron cross sections. COMMARA-2.0 library contains neutron cross section covariances for 12 light nuclei (coolants and moderators), 78 structural materials and fission products, and 20 actinides. Covariances are given in 33-energy groups, from 10?5 eV to 19.6 MeV, obtained by processing with LANL processing code NJOY using 1/E flux. In addition to these 110 files, the library contains 20 files with nu-bar covariances, 3 files with covariances of prompt fission neutron spectra (238,239,240-Pu), and 2 files with mu-bar covariances (23-Na, 56-Fe). Over the period of three years several working versions of the library have been released and tested by ANL and INL reactor analysts. Useful feedback has been collected allowing gradual improvements of the library. In addition, QA system was developed to check basic properties and features of the whole library, allowing visual inspection of uncertainty and correlations plots, inspection of uncertainties of integral quantities with independent databases, and dispersion of cross sections between major evaluated libraries. The COMMARA-2.0 beta version of the library was released to ANL and INL reactor analysts in October 2010. The final version, described in the present report, was released in March 2011.

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

    NASA Technical Reports Server (NTRS)

    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.

  6. Fission cross section measurements of actinides at LANSCE

    SciTech Connect

    Tovesson, Fredrik; Laptev, Alexander B; Hill, Tony S

    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.

  7. Absolute electron scattering cross sections for the CF2 radical.

    PubMed

    Maddern, Todd M; Hargreaves, Leigh R; Francis-Staite, Jessica R; Brunger, Michael J; Buckman, Stephen J; Winstead, Carl; McKoy, Vincent

    2008-02-15

    Using a crossed electron-molecular beam experiment, featuring a skimmed nozzle beam with pyrolytic radical production, absolute elastic cross sections for electron scattering from the CF2 molecule have been measured. A new technique for placing measured cross sections on an absolute scale is used for molecular beams produced as skimmed supersonic jets. Absolute differential cross sections for CF2 are reported for incident electron energies of 30-50 eV and over an angular range of 20-135 deg. Integral cross sections are subsequently derived from those data. The present data are compared to new theoretical predictions for the differential and integral scattering cross sections, as calculated with the Schwinger multichannel variational method using the static-exchange and static-exchange plus polarization approximations. PMID:18352469

  8. Combined inclusive diffractive cross sections measured with forward proton spectrometers at HERA

    SciTech Connect

    Ruspa, Marta; Collaboration: H1 Collaboration; ZEUS Collaboration

    2013-04-15

    A combination is presented of the inclusive diffractive cross section measurements made by the H1 and ZEUS Collaborations at HERA. The analysis uses samples of diffractive deep inelastic scattering data where leading protons are detected by dedicated spectrometers. Correlations of systematic uncertainties are taken into account by the combination method, resulting in improved precision.

  9. Applicability of the statistical theory to describing cross sections of (n, xn) and (n, xnf) reactions in fissile nuclei

    SciTech Connect

    Bychkov, V.M.; Plyaskin, V.I.

    1981-09-01

    Simple formulas for calculating the (n, xn) and (n, xnf) cross sections in heavy nuclei are obtained using the statistical theory and the exciton model of pre-equilibrium decay. It is shown that the inclusion of nonstatistical effects is important for the correct description of these cross sections in the range of neutron energies considered (5--20 MeV) and that the influence of nonequilibrium processes in the neutron channel becomes more important as the fissility of the nuclei increases.

  10. Measurements of the breakup and neutron removal cross sections for {sup 16}C

    SciTech Connect

    Ashwood, N. I.; Freer, M.; Clarke, N.M.; Curtis, N.; Soic, N.; Ziman, V.A.; Angelique, J.C.; Lecouey, J.L.; Marques, F.M.; Normand, G.; Orr, N.A.; Timis, C.; Bouchat, V.; Hanappe, F.; Kerckx, Y.; Materna, T.; Catford, W.N.; Dorvaux, O.; Stuttge, L.

    2004-12-01

    Measurements of the breakup and the neutron removal reactions of {sup 16}C have been made at 46 MeV/A and the decay cross sections measured. A correlation between the cluster breakup channels and the reaction Q value suggests that the reaction mechanism is strongly linked to quasielastic processes. No enhancement of the two-body cluster breakup cross section is seen for {sup 16}C. This result would indicate that {sup 16}C does not have a well developed cluster structure in the ground state, in agreement with recent calculations.

  11. Systematics of Fission Cross Sections in the MeV Range

    SciTech Connect

    Westfall, Robert Michael; Wright, Richard Q

    2009-01-01

    Twenty-nine years ago J. W. Behrens published a paper on the systematics of fission cross sections (3 5 MeV average). His study included 57 isotopes of elements ranging from radium through einsteinium (Z = 88 to 99). A systematic trend was seen for the element range from protactinium through curium. For a given element, the fission cross section decreased as the A-number increased. Fission cross sections are considerably more accurate now than those available in 1980. The current study represents an update of the Behrens study. Data for 11 elements and 53 nuclides were used. Trends for both the (Z,A) variation and the (2Z N) correlation are demonstrated. The current study clearly shows that the trends are quite well represented by straight lines. The trend for the fission cross sections of a given element to decrease with increasing A-number is observed for values of A < 248. For A > 248 there is a trend for the fission cross section to increase with increasing A-number.

  12. Combination of differential D?± cross-section measurements in deep-inelastic ep scattering at HERA

    NASA Astrophysics Data System (ADS)

    Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Andreev, V.; Antonelli, S.; Aushev, V.; Aushev, Y.; Baghdasaryan, A.; Begzsuren, K.; Behnke, O.; Behrens, U.; Belousov, A.; Bertolin, A.; Bloch, I.; Boos, E. G.; Borras, K.; Boudry, V.; Brandt, G.; Brisson, V.; Britzger, D.; Brock, I.; Brook, N. H.; Brugnera, R.; Bruni, A.; Buniatyan, A.; Bussey, P. J.; Bylinkin, A.; Bystritskaya, L.; Caldwell, A.; Campbell, A. J.; Avila, K. B. Cantun; Capua, M.; Catterall, C. D.; Ceccopieri, F.; Cerny, K.; Chekelian, V.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Contreras, J. G.; Cooper-Sarkar, A. M.; Corradi, M.; Corriveau, F.; Cvach, J.; Dainton, J. B.; Daum, K.; Dementiev, R. K.; Devenish, R. C. E.; Diaconu, C.; Dobre, M.; Dodonov, V.; Dolinska, G.; Dusini, S.; Eckerlin, G.; Egli, S.; Elsen, E.; Favart, L.; Fedotov, A.; Feltesse, J.; Ferencei, J.; Figiel, J.; Fleischer, M.; Fomenko, A.; Foster, B.; Gabathuler, E.; Gach, G.; Gallo, E.; Garfagnini, A.; Gayler, J.; Geiser, A.; Ghazaryan, S.; Gizhko, A.; Gladilin, L. K.; Goerlich, L.; Gogitidze, N.; Golubkov, Yu. A.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Grebenyuk, J.; Greenshaw, T.; Gregor, I.; Grindhammer, G.; Grzelak, G.; Gueta, O.; Guzik, M.; Haidt, D.; Hain, W.; Henderson, R. C. W.; Hladky, J.; Hochman, D.; Hoffmann, D.; Hori, R.; Horisberger, R.; Hreus, T.; Huber, F.; Ibrahim, Z. A.; Iga, Y.; Ishitsuka, M.; Iudin, A.; Jacquet, M.; Janssen, X.; Januschek, F.; Jomhari, N. Z.; Jung, A. W.; Jung, H.; Kadenko, I.; Kananov, S.; Kapichine, M.; Karshon, U.; Kaur, M.; Kaur, P.; Kiesling, C.; Kisielewska, D.; Klanner, R.; Klein, M.; Klein, U.; Kleinwort, C.; Kogler, R.; Kondrashova, N.; Kononenko, O.; Korol, Ie.; Korzhavina, I. A.; Kostka, P.; Kotanski, A.; Kötz, U.; Kovalchuk, N.; Kowalski, H.; Kretzschmar, J.; Krüger, K.; Krupa, B.; Kuprash, O.; Kuze, M.; Landon, M. P. J.; Lange, W.; Laycock, P.; Lebedev, A.; Levchenko, B. B.; Levonian, S.; Levy, A.; Libov, V.; Limentani, S.; Lipka, K.; Lisovyi, M.; List, B.; List, J.; Lobodzinska, E.; Lobodzinski, B.; Löhr, B.; Lohrmann, E.; Longhin, A.; Lontkovskyi, D.; Lukina, O. Yu.; Makarenko, I.; Malinovski, E.; Malka, J.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Mergelmeyer, S.; Meyer, A. B.; Meyer, H.; Meyer, J.; Mikocki, S.; Mohamad Idris, F.; Morozov, A.; Muhammad Nasir, N.; Müller, K.; Myronenko, V.; Nagano, K.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nobe, T.; Notz, D.; Nowak, G.; Nowak, R. J.; Olsson, J. E.; Onishchuk, Yu.; Ozerov, D.; Pahl, P.; Pascaud, C.; Patel, G. D.; Paul, E.; Perez, E.; Perlanski, W.; Petrukhin, A.; Picuric, I.; Pirumov, H.; Pitzl, D.; Pla?akyt?, R.; Pokorny, B.; Pokrovskiy, N. S.; Polifka, R.; Przybycien, M.; Radescu, V.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roloff, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Rubinsky, I.; Rusakov, S.; Ruspa, M.; Šálek, D.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Saxon, D. H.; Schioppa, M.; Schmidke, W. B.; Schmitt, S.; Schneekloth, U.; Schoeffel, L.; Schöning, A.; Schörner-Sadenius, T.; Sefkow, F.; Shcheglova, L. M.; Shevchenko, R.; Shkola, O.; Shushkevich, S.; Shyrma, Yu.; Singh, I.; Skillicorn, I. O.; Slominski, W.; Solano, A.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Stanco, L.; Steder, M.; Stefaniuk, N.; Stern, A.; Stopa, P.; Straumann, U.; Sykora, T.; Sztuk-Dambietz, J.; Szuba, D.; Szuba, J.; Tassi, E.; Thompson, P. D.; Tokushuku, K.; Tomaszewska, J.; Traynor, D.; Trofymov, A.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Tsurugai, T.; Turcato, M.; Turkot, O.; Turnau, J.; Tymieniecka, T.; Valkárová, A.; Vallée, C.; Van Mechelen, P.; Vazdik, Y.; Verbytskyi, A.; Viazlo, O.; Walczak, R.; Wan Abdullah, W. A. T.; Wegener, D.; Wichmann, K.; Wing, M.; Wolf, G.; Wünsch, E.; Yamada, S.; Yamazaki, Y.; Žá?ek, J.; Zakharchuk, N.; ?arnecki, A. F.; Zawiejski, L.; Zenaiev, O.; Zhang, Z.; Zhautykov, B. O.; Zhmak, N.; Žleb?ík, R.; Zohrabyan, H.; Zomer, F.; Zotkin, D. S.

    2015-09-01

    H1 and ZEUS have published single-differential cross sections for inclusive D ?±-meson production in deep-inelastic ep scattering at HERA from their respective final data sets. These cross sections are combined in the common visible phase-space region of photon virtuality Q 2 > 5 GeV2, electron inelasticity 0 .02 < y < 0 .7 and the D ?± meson's transverse momentum p T( D ?) > 1 .5 GeV and pseudorapidity | ?( D ?)| < 1 .5. The combination procedure takes into account all correlations, yielding significantly reduced experimental uncertainties. Double-differential cross sections d2 ?/d Q 2d y are combined with earlier D ?± data, extending the kinematic range down to Q 2 > 1 .5 GeV2. Perturbative next-to-leading-order QCD predictions are compared to the results.

  13. PRACTICAL METHOD FOR ESTIMATING NEUTRON CROSS SECTION COVARIANCES IN THE RESONANCE REGION

    SciTech Connect

    Cho, Y.S.; Oblozinsky, P.; Mughabghab,S.F.; Mattoon,C.M.; Herman,M.

    2010-04-30

    Recent evaluations of neutron cross section covariances in the resolved resonance region reveal the need for further research in this area. Major issues include declining uncertainties in multigroup representations and proper treatment of scattering radius uncertainty. To address these issues, the present work introduces a practical method based on kernel approximation using resonance parameter uncertainties from the Atlas of Neutron Resonances. Analytical expressions derived for average cross sections in broader energy bins along with their sensitivities provide transparent tool for determining cross section uncertainties. The role of resonance-resonance and bin-bin correlations is specifically studied. As an example we apply this approach to estimate (n,{gamma}) and (n,el) covariances for the structural material {sup 55}Mn.

  14. Electron impact rotationally elastic total cross section for formamide

    SciTech Connect

    Vinodkumar, Minaxi; Limbachiya, Chetan; Desai, Hardik Vinodkumar, P. C.

    2014-09-28

    This paper reports computational results of the total cross sections for electron impact on formamide (HCONH?) over a wide range of energies from 0.01 eV to 5 keV. Total cross sections over such a wide range are reported for the first time as the earlier reported data is up to maximum of 12 eV. Below ionization threshold of the target, we performed ab initio calculations using UK molecular R-Matrix code within static, exchange plus polarization (SEP), and close coupling approximations. Twenty eight target states are included in close coupling formalism. Total 350 channels and 2410 configuration state functions are included in the calculations. We observe a ?* shape resonance at 3.41 eV and a ?* resonance at 15.3 eV as against similar resonances reported at 3.77 eV and 14.9 eV, respectively, by Goumans et al. [J. Chem. Theory Comput. 5, 217 (2009)] using SEP model. The cross sections at higher energies are evaluated using the spherical complex optical potential formalism. The two methods are found to be consistent with a smooth cross over at 18 eV. The vertical excitation energies, electronic excitation cross sections, differential cross sections, momentum transfer, and total cross sections are computed. In absence of experimental data, we compared our computed total cross sections with available other theoretical results.

  15. Cross Section Sensitivity and Propagated Errors in HZE Exposures

    NASA Technical Reports Server (NTRS)

    Heinbockel, John H.; Wilson, John W.; Blatnig, Steve R.; Qualls, Garry D.; Badavi, Francis F.; Cucinotta, Francis A.

    2005-01-01

    It has long been recognized that galactic cosmic rays are of such high energy that they tend to pass through available shielding materials resulting in exposure of astronauts and equipment within space vehicles and habitats. Any protection provided by shielding materials result not so much from stopping such particles but by changing their physical character in interaction with shielding material nuclei forming, hopefully, less dangerous species. Clearly, the fidelity of the nuclear cross-sections is essential to correct specification of shield design and sensitivity to cross-section error is important in guiding experimental validation of cross-section models and database. We examine the Boltzmann transport equation which is used to calculate dose equivalent during solar minimum, with units (cSv/yr), associated with various depths of shielding materials. The dose equivalent is a weighted sum of contributions from neutrons, protons, light ions, medium ions and heavy ions. We investigate the sensitivity of dose equivalent calculations due to errors in nuclear fragmentation cross-sections. We do this error analysis for all possible projectile-fragment combinations (14,365 such combinations) to estimate the sensitivity of the shielding calculations to errors in the nuclear fragmentation cross-sections. Numerical differentiation with respect to the cross-sections will be evaluated in a broad class of materials including polyethylene, aluminum and copper. We will identify the most important cross-sections for further experimental study and evaluate their impact on propagated errors in shielding estimates.

  16. Measurement of the scattering cross section of slow neutrons on liquid parahydrogen from neutron transmission

    NASA Astrophysics Data System (ADS)

    Grammer, K. B.; Alarcon, R.; Barrón-Palos, L.; Blyth, D.; Bowman, J. D.; Calarco, J.; Crawford, C.; Craycraft, K.; Evans, D.; Fomin, N.; Fry, J.; Gericke, M.; Gillis, R. C.; Greene, G. L.; Hamblen, J.; Hayes, C.; Kucuker, S.; Mahurin, R.; Maldonado-Velázquez, M.; Martin, E.; McCrea, M.; Mueller, P. E.; Musgrave, M.; Nann, H.; Penttilä, S. I.; Snow, W. M.; Tang, Z.; Wilburn, W. S.

    2015-05-01

    Liquid hydrogen is a dense Bose fluid whose equilibrium properties are both calculable from first principles using various theoretical approaches and of interest for the understanding of a wide range of questions in many-body physics. Unfortunately, the pair correlation function g (r ) inferred from neutron scattering measurements of the differential cross section d/? d ? from different measurements reported in the literature are inconsistent. We have measured the energy dependence of the total cross section and the scattering cross section for slow neutrons with energies between 0.43 and 16.1 meV on liquid hydrogen at 15.6 K (which is dominated by the parahydrogen component) using neutron transmission measurements on the hydrogen target of the NPDGamma collaboration at the Spallation Neutron Source at Oak Ridge National Laboratory. The relationship between the neutron transmission measurement we perform and the total cross section is unambiguous, and the energy range accesses length scales where the pair correlation function is rapidly varying. At 1 meV our measurement is a factor of 3 below the data from previous work. We present evidence that these previous measurements of the hydrogen cross section, which assumed that the equilibrium value for the ratio of orthohydrogen and parahydrogen has been reached in the target liquid, were in fact contaminated with an extra nonequilibrium component of orthohydrogen. Liquid parahydrogen is also a widely used neutron moderator medium, and an accurate knowledge of its slow neutron cross section is essential for the design and optimization of intense slow neutron sources. We describe our measurements and compare them with previous work.

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

    SciTech Connect

    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.

  18. Characterization of Cross-Sectioned Gallium Nitride High-Electron-Mobility Transistors with In Situ Biasing

    NASA Astrophysics Data System (ADS)

    Hilton, A. M.; Brown, J. L.; Moore, E. A.; Hoelscher, J. A.; Heller, E. R.; Dorsey, D. L.

    2015-10-01

    AlGaN/GaN high-electron-mobility transistors (HEMTs) were characterized in cross-section by Kelvin probe force microscopy (KPFM) during in situ biasing. The HEMTs used in this study were specially designed to maintain full and representative transistor functionality after cross-sectioning perpendicular to the gate width dimension to expose the active channel from source to drain. A cross-sectioning procedure was established that produces samples with high-quality surfaces and minimal degradation in initial transistor performance. A detailed description of the cross-sectioning procedure is provided. Samples were characterized by KPFM, effectively mapping the surface potential of the device in two-dimensional cross-section, including under metallization layers (i.e., gate, field plates, and ohmic contacts). Under the gate and field plate layers are where electric field, temperature, and temperature gradients are all most commonly predicted to have peak values, and where degradation and failure are most likely, and so this is where direct measurements are most critical. In this work, the surface potential of the operating device was mapped in cross-section by KPFM. Charge redistribution was observed during and after biasing, and the surface potential was seen to decay with time back to the prebias condition. This work is a first step toward directly mapping and localizing the steady-state and transient charge distribution due to point defects (traps) before, during, and after device operation, including normally inaccessible regions such as under metallization layers. Such measurements have not previously been demonstrated for GaN HEMT technology.

  19. Neutron inelastic cross-section measurements for Mg24

    NASA Astrophysics Data System (ADS)

    Olacel, A.; Borcea, C.; Dessagne, P.; Kerveno, M.; Negret, A.; Plompen, A. J. M.

    2014-09-01

    The ? production cross sections from neutron inelastic scattering on 24Mg were measured for neutron energies up to 18 MeV at GELINA (the Geel Linear Accelerator), the neutron source operated by EC-JRC-IRMM, Belgium. The level cross section and the total inelastic cross section were determined. We used the GAINS (Gamma Array for Inelastic Neutron Scattering) spectrometer with seven large-volume high-purity germanium (HPGe) detectors placed at 110? and 150? with respect to the beam direction. The neutron flux was determined with a U235 fission chamber. The results are compared with calculations performed with the talys 1.6 code using the default settings.

  20. Actinide Neutron-Induced Fission Cross Section Measurements At LANSCE

    SciTech Connect

    Tovesson, F.; Laptev, A. B.; Hill, T. S.

    2011-06-01

    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. Parallel-plate ionization chambers 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 existing evaluations and previous data.

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

    E-print Network

    Nakagawa, T

    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.

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

    SciTech Connect

    Tovesson, Fredrik K; Laptev, Alexander B; Hill, Tony S

    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.

  3. The impact of television viewing on brain structures: cross-sectional and longitudinal analyses.

    PubMed

    Takeuchi, Hikaru; Taki, Yasuyuki; Hashizume, Hiroshi; Asano, Kohei; Asano, Michiko; Sassa, Yuko; Yokota, Susumu; Kotozaki, Yuka; Nouchi, Rui; Kawashima, Ryuta

    2015-05-01

    Television (TV) viewing is known to affect children's verbal abilities and other physical, cognitive, and emotional development in psychological studies. However, the brain structural development associated with TV viewing has never been investigated. Here we examined cross-sectional correlations between the duration of TV viewing and regional gray/white matter volume (rGMV/rWMV) among 133 boys and 143 girls as well as correlations between the duration of TV viewing and longitudinal changes that occurred a few years later among 111 boys and 105 girls. After correcting for confounding factors, we found positive effects of TV viewing on rGMV of the frontopolar and medial prefrontal areas in cross-sectional and longitudinal analyses, positive effects of TV viewing on rGMV/rWMV of areas of the visual cortex in cross-sectional analyses, and positive effects of TV viewing on rGMV of the hypothalamus/septum and sensorimotor areas in longitudinal analyses. We also confirmed negative effects of TV viewing on verbal intelligence quotient (IQ) in cross-sectional and longitudinal analyses. These anatomical correlates may be linked to previously known effects of TV viewing on verbal competence, aggression, and physical activity. In particular, the present results showed effects of TV viewing on the frontopolar area of the brain, which has been associated with intellectual abilities. PMID:24256892

  4. Double parton scattering: A study of the effective cross section within a Light-Front quark model

    NASA Astrophysics Data System (ADS)

    Rinaldi, Matteo; Scopetta, Sergio; Traini, Marco; Vento, Vicente

    2016-01-01

    We present a calculation of the effective cross section ?eff, an important ingredient in the description of double parton scattering in proton-proton collisions. Our theoretical approach makes use of a Light-Front quark model as a framework to calculate the double parton distribution functions at low-resolution scale. QCD evolution is implemented to reach the experimental scale. The obtained values of ?eff in the valence region are consistent with the present experimental scenario, in particular with the sets of data which include the same kinematical range. However the result of the complete calculation shows a dependence of ?eff on xi, a feature not easily seen in the available data, probably because of their low accuracy. Measurements of ?eff in restricted xi regions are addressed to obtain indications on double parton correlations, a novel and interesting aspect of the three dimensional structure of the nucleon.

  5. Covariances for neutron cross sections calculated using a regional model based on local-model fits to experimental data

    SciTech Connect

    Smith, D.L.; Guenther, P.T.

    1983-11-01

    We suggest a procedure for estimating uncertainties in neutron cross sections calculated with a nuclear model descriptive of a specific mass region. It applies standard error propagation techniques, using a model-parameter covariance matrix. Generally, available codes do not generate covariance information in conjunction with their fitting algorithms. Therefore, we resort to estimating a relative covariance matrix a posteriori from a statistical examination of the scatter of elemental parameter values about the regional representation. We numerically demonstrate our method by considering an optical-statistical model analysis of a body of total and elastic scattering data for the light fission-fragment mass region. In this example, strong uncertainty correlations emerge and they conspire to reduce estimated errors to some 50% of those obtained from a naive uncorrelated summation in quadrature. 37 references.

  6. Excited state cross sections for Er-doped glasses

    NASA Astrophysics Data System (ADS)

    Zemon, Stanley A.; Lambert, Gary M.; Miniscalco, William J.; Davies, Richard W.; Hall, Bruce T.; Folweiler, Robert C.; Wei, Ta-Sheng; Andrews, Leonard J.; Singh, Mahendra P.

    1991-01-01

    Excited-state-absorption (ESA) cross sections were determined for the region between 760 and 900 nm for Er-doped fluorophosphate phosphate and silicate glasses. Measurements were performed on multimode fibers pumping at 647 nm with powers 1 . 5 Wto invert the population into the saturation regime. Over much of the 800-nm band ground-state-absorption (GSA) cross sections are equal to or greater than ESA cross sections. For comparison ESA was also measured for singlemode Al/P-doped silica fiber. The cross sections were incorporated into an amplifier model and the phosphate and fluorophosphate glasses were found to provide higher gain than silica for pumping in the 800-nm band. Photoexcited fluorozirconates were found to have substantial populations in the first four excited states and ESA transitions originating from these states are identified.

  7. Non Standard Interaction in Neutrino-Electron Cross Section

    SciTech Connect

    Barranco, J.

    2006-01-06

    The present status of non standard interaction (NSI) in v - e scattering cross section is reviewed and future perspectives are presented showing the importance of low energy neutrino experiments in the measurement of such interactions.

  8. Measurement of the Z ? ?? cross section with the ATLAS detector

    SciTech Connect

    Aad, G.; Abbott, B.; Abdallah, J.; Abdelalim, A. A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Abreu, H.; Acerbi, E.; Acharya, B. S.; Adams, D. L.; Addy, T. N.; Adelman, J.; Aderholz, M.; Adomeit, S.; Adragna, P.; Adye, T.; Aefsky, S.; Aguilar-Saavedra, J. A.; Siegrist, James L.

    2011-12-01

    The Z ? ?? cross section is measured with the ATLAS experiment at the LHC in four different final states determined by the decay modes of the {tau} leptons: muon-hadron, electron-hadron, electron-muon, and muon-muon. The analysis is based on a data sample corresponding to an integrated luminosity of 36 pb?¹, at a proton-proton center-of-mass energy of ?s = 7 TeV. Cross sections are measured separately for each final state in fiducial regions of high detector acceptance, as well as in the full phase space, over the mass region 66-116 GeV. The individual cross sections are combined and the product of the total Z production cross section and Z ? ?? branching fraction is measured to be 0.97 ± 0.07(stat) ± 0.06(syst) ± 0.03(lumi) nb, in agreement with next-to-next-to-leading order calculations.

  9. Extraordinarily Large Optical Cross Section for Localized Single Nanoresonator

    NASA Astrophysics Data System (ADS)

    Zhou, Ming; Shi, Lei; Zi, Jian; Yu, Zongfu

    2015-07-01

    Using an optical nanoresonator to realize extreme concentration of light at subwavelength nanoscale dimensions is of both fundamental and practical significance. Unfortunately, the optical cross section of an isotropic nanoresonator is determined by the resonant wavelength, which unfavorably limits the highest concentration ratio. Here we show that the cross section of a localized subwavelength resonator can be drastically enhanced by orders of magnitude. A single microscopic nanoresonator could exhibit a macroscopic optical cross section. We further show that the enhancement can be implemented in simple dielectric structures that are readily compatible with optoelectronic integration. The giant optical cross section of a nano-object provides a versatile platform to create extremely strong light-matter interactions at the nanoscale.

  10. Scaling of Cross Sections for Ion-atom Impact Ionization

    E-print Network

    Kaganovich, I D; Startsev, E

    2003-01-01

    The values of ion-atom ionization cross sections are frequently needed for many applications that utilize the propagation of fast ions through matter. When experimental data and theoretical calculations are not available, approximate formulas are frequently used. This paper briefly summarizes the most important theoretical results and approaches to cross section calculations in order to place the discussion in historical perspective and offer a concise introduction to the topic. Based on experimental data and theoretical predictions, a new fit for ionization cross sections is proposed. The range of validity and accuracy of several frequently used approximations (classical trajectory, the Born approximation, and so forth) are discussed using, as examples, the ionization cross sections of hydrogen and helium atoms by various fully stripped ions.

  11. Giant dipole resonance parameters with uncertainties from photonuclear cross sections

    SciTech Connect

    Plujko, V.A.; Capote, R.; Gorbachenko, O.M.

    2011-09-15

    Updated values and corresponding uncertainties of isovector giant dipole resonance (IVGDR or GDR) model parameters are presented that are obtained by the least-squares fitting of theoretical photoabsorption cross sections to experimental data. The theoretical photoabsorption cross section is taken as a sum of the components corresponding to excitation of the GDR and quasideuteron contribution to the experimental photoabsorption cross section. The present compilation covers experimental data as of January 2010. - Highlights: {yields} Experimental {sigma} ({gamma}, abs) or a sum of partial cross sections are taken as input to the fitting. {yields} Data include contributions from photoproton reactions. {yields} Standard (SLO) or modified (SMLO) Lorentzian approaches are used for formulating GDR models. {yields} Spherical or axially deformed nuclear shapes are used in GDR least-squares fit. {yields} Values and uncertainties of the SLO and SMLO GDR model parameters are tabulated.

  12. Cross section for the subthreshold fission of {sup 236}U

    SciTech Connect

    Alekseev, A. A.; Bergman, A. A.; Berlev, A. I.; Koptelov, E. A.; Samylin, B. F.; Trufanov, A. M.; Fursov, B. I.; Shorin, V. S.

    2008-08-15

    The cross section for {sup 236}U fission in the neutron-energy range E{sub n} = 0.001-20 keV was measured by using the INR RAS (Institute of Nuclear Research, Russian Academy of Sciences, Moscow) LSDS-100 neutron spectrometer of the lead slowing-down spectrometer type. The resonance fission areas of the resonances at 5.45 eV and 1.28 keV were found, and the fission widths of these resonances were evaluated. The cross section for the {sup 238}U(n, f) fission process was measured, and the threshold sensitivity of the LSDS-100 to small values of fission cross sections was estimated. The well-known intermediate structure in the cross section for the neutron-induced subbarrier fission of {sup 236}U was confirmed.

  13. 12. CLOSEUP VIEW OF CROSS SECTION OF SPILLWAY FIFTY FEET ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. CLOSE-UP VIEW OF CROSS SECTION OF SPILLWAY FIFTY FEET FROM LAKESHORE, SHOWING REMAINS OF SPILLWAY TIMBERS, LOOKING WEST - Three Bears Lake & Dams, North of Marias Pass, East Glacier Park, Glacier County, MT

  14. 4. DETAIL VIEW OF CROSS SECTION OF STRUCTURE, SHOWING EXTERIOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. DETAIL VIEW OF CROSS SECTION OF STRUCTURE, SHOWING EXTERIOR FACINGS LINED WITH RUBBLE BACKING AND EARTH INFILL, LOOKING EAST - Rock Wall, North side of Battle Creek Canyon, Shingletown, Shasta County, CA

  15. 36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER PLANT, LOOKING NORTH. ONLY TWO OF THE THREE UNITS ARE VISIBLE - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  16. 20. CROSS SECTIONAL VIEW OF HORSE MESA, SHOWING RIGHT SPILLWAY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. CROSS SECTIONAL VIEW OF HORSE MESA, SHOWING RIGHT SPILLWAY SUPERSTRUCTURE AND CONCRETE PLACEMENT LINES August 2, 1927 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  17. Measurement of the Z??? cross section with the ATLAS detector

    NASA Astrophysics Data System (ADS)

    Aad, G.; Abbott, B.; Abdallah, J.; Abdelalim, A. A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Abreu, H.; Acerbi, E.; Acharya, B. S.; Adams, D. L.; Addy, T. N.; Adelman, J.; Aderholz, M.; Adomeit, S.; Adragna, P.; Adye, T.; Aefsky, S.; Aguilar-Saavedra, J. A.; Aharrouche, M.; Ahlen, S. P.; Ahles, F.; Ahmad, A.; Ahsan, M.; Aielli, G.; Akdogan, T.; Åkesson, T. P. A.; Akimoto, G.; Akimov, A. V.; Akiyama, A.; Alam, M. S.; Alam, M. A.; Albert, J.; Albrand, S.; Aleksa, M.; Aleksandrov, I. N.; Alessandria, F.; Alexa, C.; Alexander, G.; Alexandre, G.; Alexopoulos, T.; Alhroob, M.; Aliev, M.; Alimonti, G.; Alison, J.; Aliyev, M.; Allport, P. P.; Allwood-Spiers, S. E.; Almond, J.; Aloisio, A.; Alon, R.; Alonso, A.; Alviggi, M. G.; Amako, K.; Amaral, P.; Amelung, C.; Ammosov, V. V.; Amorim, A.; Amorós, G.; Amram, N.; Anastopoulos, C.; Andari, N.; Andeen, T.; Anders, C. F.; Anderson, K. J.; Andreazza, A.; Andrei, V.; Andrieux, M.-L.; Anduaga, X. S.; Angerami, A.; Anghinolfi, F.; Anjos, N.; Annovi, A.; Antonaki, A.; Antonelli, M.; Antonov, A.; Antos, J.; Anulli, F.; Aoun, S.; Aperio Bella, L.; Apolle, R.; Arabidze, G.; Aracena, I.; Arai, Y.; Arce, A. T. H.; Archambault, J. P.; Arfaoui, S.; Arguin, J.-F.; Arik, E.; Arik, M.; Armbruster, A. J.; Arnaez, O.; Arnault, C.; Artamonov, A.; Artoni, G.; Arutinov, D.; Asai, S.; Asfandiyarov, R.; Ask, S.; Åsman, B.; Asquith, L.; Assamagan, K.; Astbury, A.; Astvatsatourov, A.; Atoian, G.; Aubert, B.; Auerbach, B.; Auge, E.; Augsten, K.; Aurousseau, M.; Austin, N.; Avolio, G.; Avramidou, R.; Axen, D.; Ay, C.; Azuelos, G.; Azuma, Y.; Baak, M. A.; Baccaglioni, G.; Bacci, C.; Bach, A. M.; Bachacou, H.; Bachas, K.; Bachy, G.; Backes, M.; Backhaus, M.; Badescu, E.; Bagnaia, P.; Bahinipati, S.; Bai, Y.; Bailey, D. C.; Bain, T.; Baines, J. T.; Baker, O. K.; Baker, M. D.; Baker, S.; Baltasar Dos Santos Pedrosa, F.; Banas, E.; Banerjee, P.; Banerjee, Sw.; Banfi, D.; Bangert, A.; Bansal, V.; Bansil, H. S.; Barak, L.; Baranov, S. P.; Barashkou, A.; Barbaro Galtieri, A.; Barber, T.; Barberio, E. L.; Barberis, D.; Barbero, M.; Bardin, D. Y.; Barillari, T.; Barisonzi, M.; Barklow, T.; Barlow, N.; Barnett, B. M.; Barnett, R. M.; Baroncelli, A.; Barone, G.; Barr, A. J.; Barreiro, F.; Barreiro Guimarães da Costa, J.; Barrillon, P.; Bartoldus, R.; Barton, A. E.; Bartsch, D.; Bartsch, V.; Bates, R. L.; Batkova, L.; Batley, J. R.; Battaglia, A.; Battistin, M.; Battistoni, G.; Bauer, F.; Bawa, H. S.; Beare, B.; Beau, T.; Beauchemin, P. H.; Beccherle, R.; Bechtle, P.; Beck, H. P.; Beckingham, M.; Becks, K. H.; Beddall, A. J.; Beddall, A.; Bedikian, S.; Bednyakov, V. A.; Bee, C. P.; Begel, M.; Behar Harpaz, S.; Behera, P. K.; Beimforde, M.; Belanger-Champagne, C.; Bell, P. J.; Bell, W. H.; Bella, G.; Bellagamba, L.; Bellina, F.; Bellomo, M.; Belloni, A.; Beloborodova, O.; Belotskiy, K.; Beltramello, O.; Ben Ami, S.; Benary, O.; Benchekroun, D.; Benchouk, C.; Bendel, M.; Benedict, B. H.; Benekos, N.; Benhammou, Y.; Benjamin, D. P.; Benoit, M.; Bensinger, J. R.; Benslama, K.; Bentvelsen, S.; Berge, D.; Bergeaas Kuutmann, E.; Berger, N.; Berghaus, F.; Berglund, E.; Beringer, J.; Bernardet, K.; Bernat, P.; Bernhard, R.; Bernius, C.; Berry, T.; Bertin, A.; Bertinelli, F.; Bertolucci, F.; Besana, M. I.; Besson, N.; Bethke, S.; Bhimji, W.; Bianchi, R. M.; Bianco, M.; Biebel, O.; Bieniek, S. P.; Biesiada, J.; Biglietti, M.; Bilokon, H.; Bindi, M.; Binet, S.; Bingul, A.; Bini, C.; Biscarat, C.; Bitenc, U.; Black, K. M.; Blair, R. E.; Blanchard, J.-B.; Blanchot, G.; Blazek, T.; Blocker, C.; Blocki, J.; Blondel, A.; Blum, W.; Blumenschein, U.; Bobbink, G. J.; Bobrovnikov, V. B.; Bocchetta, S. S.; Bocci, A.; Boddy, C. R.; Boehler, M.; Boek, J.; Boelaert, N.; Böser, S.; Bogaerts, J. A.; Bogdanchikov, A.; Bogouch, A.; Bohm, C.; Boisvert, V.; Bold, T.; Boldea, V.; Bolnet, N. M.; Bona, M.; Bondarenko, V. G.; Boonekamp, M.; Boorman, G.; Booth, C. N.; Bordoni, S.; Borer, C.; Borisov, A.; Borissov, G.; Borjanovic, I.; Borroni, S.; Bos, K.; Boscherini, D.; Bosman, M.; Boterenbrood, H.; Botterill, D.; Bouchami, J.; Boudreau, J.; Bouhova-Thacker, E. V.; Boulahouache, C.; Bourdarios, C.; Bousson, N.; Boveia, A.; Boyd, J.; Boyko, I. R.; Bozhko, N. I.; Bozovic-Jelisavcic, I.; Bracinik, J.; Braem, A.; Branchini, P.; Brandenburg, G. W.; Brandt, A.; Brandt, G.; Brandt, O.; Bratzler, U.; Brau, B.; Brau, J. E.; Braun, H. M.; Brelier, B.; Bremer, J.; Brenner, R.; Bressler, S.; Breton, D.; Britton, D.; Brochu, F. M.; Brock, I.; Brock, R.; Brodbeck, T. J.; Brodet, E.; Broggi, F.; Bromberg, C.; Brooijmans, G.; Brooks, W. K.; Brown, G.; Brown, H.; Bruckman de Renstrom, P. A.; Bruncko, D.; Bruneliere, R.; Brunet, S.; Bruni, A.; Bruni, G.; Bruschi, M.; Buanes, T.; Bucci, F.; Buchanan, J.

    2011-12-01

    The Z??? cross section is measured with the ATLAS experiment at the LHC in four different final states determined by the decay modes of the ? leptons: muon-hadron, electron-hadron, electron-muon, and muon-muon. The analysis is based on a data sample corresponding to an integrated luminosity of 36pb-1, at a proton-proton center-of-mass energy of s=7TeV. Cross sections are measured separately for each final state in fiducial regions of high detector acceptance, as well as in the full phase space, over the mass region 66-116 GeV. The individual cross sections are combined and the product of the total Z production cross section and Z??? branching fraction is measured to be 0.97±0.07(stat)±0.06(syst)±0.03(lumi)nb, in agreement with next-to-next-to-leading order calculations.

  18. Dielectronic Recombination Cross-Sections of Fluorinelike Xenon 

    E-print Network

    Dewitt, D. R.; Schneider, D.; Chen, M. H.; Schneider, M. B.; Church, David A.; Weinberg, G.; Sakurai, M.

    1993-01-01

    Measurements of relative dielectronic recombination (DR) cross sections for fluorinelike xenon (Xe45+) are presented. Recombination takes place in an electron-beam ion trap, where decay rates are obtained as the ions recombine with beam electrons...

  19. Dielectronic-Recombination Cross-Sections of Hydrogenlike Argon 

    E-print Network

    Dewitt, D. R.; Schneider, D.; Clark, M. W.; Chen, M. H.; Church, David A.

    1991-01-01

    of the formation and interaction of ions with electrons in an ion trap followed by an analysis of the extracted ions to determine relative yields. Comparison with theory shows that the total cross sections agree within +/- 6%....

  20. 8. VIEW OF CROSS SECTION OF THE EASTERNMOST WALL SEGMENT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW OF CROSS SECTION OF THE EASTERNMOST WALL SEGMENT THAT SHOWS THE TRENCHING AND 1960 PIPELINE CORRIDOR BETWEEN THE WALL SEGMENTS, LOOKING WEST-NORTHWEST - Rock Wall, North side of Battle Creek Canyon, Shingletown, Shasta County, CA

  1. Scaling Cross Sections for Ion-atom Impact Ionization

    SciTech Connect

    Igor D. Kaganovich; Edward Startsev; Ronald C. Davidson

    2003-06-06

    The values of ion-atom ionization cross sections are frequently needed for many applications that utilize the propagation of fast ions through matter. When experimental data and theoretical calculations are not available, approximate formulas are frequently used. This paper briefly summarizes the most important theoretical results and approaches to cross section calculations in order to place the discussion in historical perspective and offer a concise introduction to the topic. Based on experimental data and theoretical predictions, a new fit for ionization cross sections is proposed. The range of validity and accuracy of several frequently used approximations (classical trajectory, the Born approximation, and so forth) are discussed using, as examples, the ionization cross sections of hydrogen and helium atoms by various fully stripped ions.

  2. 28. CROSS SECTION OF A RECTANGULAR COKE OVEN SHOWING THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. CROSS SECTION OF A RECTANGULAR COKE OVEN SHOWING THE INTERNAL STRUCTURE OF THE OVEN. - Tower Hill No. 2 Mine, Approximately 0.47 mile Southwest of intersection of Stone Church Road & Township Route 561, Hibbs, Fayette County, PA

  3. New Kr Cross Sections and Astrophysical Constraints on Presolar Grains

    SciTech Connect

    Mutti, P.; Beer, H.; Brusegan, A.; Corvi, F.; Gallino, R.

    2005-05-24

    A series of neutron-capture cross-section measurements on various krypton isotopes has been performed at the Geel Electron Linear Accelerator (GELINA). The total cross section of 84Kr and the capture cross section of 86Kr and 82Kr have been measured in the energy range from 0 up to 400 keV. Moreover, capture cross-section data for 80Kr and 83Kr have been obtained for a limited energy range, namely from 0 up to 5 keV, from a natural krypton sample. The main goal of the measurement campaign was to provide reliable nuclear data for s-process nucleosynthesis calculation. We performed a series of calculations for stars with mass from M = 1.5M{center_dot} to M = 3M{center_dot} and metallicity from solar down to 1/6 of solar with the aim to reproduce the krypton isotopic ratios found in silicon-carbide grains.

  4. Automating the Modeling of the SEE Cross Section's Angular Dependence

    NASA Technical Reports Server (NTRS)

    Patterson, J. D.; Edmonds, L. D.

    2003-01-01

    An algorithm that automates the application of the alpha law in any SEE analysis is presented. This automation is essential for the widespread acceptance of the sophisticated cross section angular dependence model.

  5. Grit and Work Engagement: A Cross-Sectional Study

    PubMed Central

    Asahi, Kentaro; Ishikawa, Yoshiki

    2015-01-01

    Grit, defined as perseverance of effort and consistency of interest, has attracted attention as a predictor of success in various fields beyond IQ and the Big Five personality dimension of Conscientiousness. The purpose of the current study was to examine previously uninvestigated questions regarding grit using a cross-sectional design among a large number of working adults in Japan. First, we tested geographical generalizability of associations between grit and orientations towards happiness by comparing previous studies in the U.S. and the current study in Japan. It was confirmed that orientation towards meaning rather than orientation towards engagement had a stronger positive correlation with grit in our sample of Japanese people. This result is inconsistent with previous studies in the U.S. Furthermore, the Big Five dimension of Openness to Experience was newly confirmed as having a positive association with grit. Second, we examined the association between grit and work engagement, which is considered as an outcome indicator for work performance. In this analysis, grit was a strong predictor for work performance as well as academic performance. PMID:26335001

  6. Awareness and Performance of Iranian Nurses with Regard to Health Economics: A Cross-Sectional Study

    PubMed Central

    Heydari, Abbas; Mazloom, Reza; Najar, Ali Vafaee; Bakhshi, Mahmoud

    2015-01-01

    Background: Health costs have risen everywhere, worldwide, and nurses play a pivotal role in cost savings and in contributing to the financial stability of hospitals. Aim: This study evaluated the awareness and performance of Iranian nursing staff, with regard to health economics. Materials and Methods: A total of 175 nurses who worked in three teaching hospitals in Mashhad (Iran) were selected for this descriptive cross-sectional study, and data were gathered via a 27-item questionnaire. Statistical analysis was performed using one-way analysis of variance, multiple regression analysis, and Pearson's correlation coefficient. Results: A total of 78% (n = 39) of nurses did not have a good awareness of health economics. The overall mean score for economic awareness was 5.9 ± 2.1 (possible range, 0-16), and for economic performance was 26.6 ± 4 (possible range, 0-44). There was a significant relationship between the economic awareness and performance of nurses, and nurses in higher positions had a greater awareness of health economics. Conclusions: Considering the inadequacy of the health economics awareness and performance of nurses, it is essential that efforts are made to enhance their knowledge and behavior with regard to economic issues and cost saving in all the fields of nursing, through the use of continuing education courses and workshops. PMID:26605201

  7. Thermal neutron capture cross sections of tellurium isotopes

    SciTech Connect

    Tomandl, I.; Honzatko, J.; von Egidy, T.; Wirth, H.-F.; Belgya, T.; Lakatos, M.; Szentmiklosi, L.; Revay, Zs.; Molnar, G.L.; Firestone, R.B.; Bondarenko, V.

    2004-03-01

    New values for thermal neutron capture cross sections of the tellurium isotopes 122Te, 124Te, 125Te, 126Te, 128Te, and 130Te are reported. These values are based on a combination of newly determined partial g-ray cross sections obtained from experiments on targets contained natural Te and gamma intensities per capture of individual Te isotopes. Isomeric ratios for the thermal neutron capture on the even tellurium isotopes are also given.

  8. Photon cross sections for ENDF/B-VI

    SciTech Connect

    Trubey, D.K.; Berger, M.J.; Hubbell, J.H.

    1989-01-01

    The PHOTX library of the National Institute of Standards and Technology will be used as the basis of File 23 (photon cross sections) for ENDF/B-VI. The PHOTX library is based on an experimental data base consisting of 21,000 data points from 512 literature sources for 82 elements. An important difference from earlier compilations is that renormalization of photo-effect cross sections is not performed. 40 refs., 12 figs.

  9. Hadronic Cross sections: from cyclotrons to colliders to cosmic rays

    E-print Network

    Martin M. Block

    2010-09-02

    We present evidence for the saturation of the Froissart bound at high energy for {\\em all hadronic} total cross sections at high energies, and use this to unify $pp$ (and $\\bar p p$) total cross sections over the energy range from cyclotrons to colliders to ultra-high energy cosmic rays, an energy span from $\\sqrt s = 4$ GeV to 80 TeV.

  10. Biomechanical Factors Associated With Jump Height: A Comparison of Cross-Sectional and Pre-to-Posttraining Change Findings.

    PubMed

    Marshall, Brendan M; Moran, Kieran A

    2015-12-01

    Marshall, BM and Moran, KA. Biomechanical factors associated with jump height: A comparison of cross-sectional and pre-to-posttraining change findings. J Strength Cond Res 29(12): 3292-3299, 2015-Previous studies investigating the biomechanical factors associated with maximal countermovement jump height have typically used cross-sectional data. An alternative but less common approach is to use pre-to-posttraining change data, where the relationship between an improvement in jump height and a change in a factor is examined more directly. Our study compared the findings of these approaches. Such an evaluation is necessary because cross-sectional studies are currently a primary source of information for coaches when examining what factors to train to enhance performance. The countermovement jump of 44 males was analyzed before and after an 8-week training intervention. Correlations with jump height were calculated using both cross-sectional (pretraining data only) and pre-to-posttraining change data. Eight factors identified in the cross-sectional analysis were not significantly correlated with a change in jump height in the pre-to-post analysis. Additionally, only 6 of 11 factors identified in the pre-to-post analysis were identified in the cross-sectional analysis. These findings imply that (a) not all factors identified in a cross-sectional analysis may be critical to jump height improvement and (b) cross-sectional analyses alone may not provide an insight into all of the potential factors to train to enhance jump height. Coaches must be aware of these limitations when examining cross-sectional studies to identify factors to train to enhance jump ability. Additional findings highlight that although exercises prescribed to improve jump height should aim to enhance concentric power production at all joints, a particular emphasis on enhancing hip joint peak power may be warranted. PMID:25992663

  11. Cross-sectional area and intensity variations of sausage modes

    NASA Astrophysics Data System (ADS)

    Moreels, M. G.; Goossens, M.; Van Doorsselaere, T.

    2013-07-01

    Context. The observations obtained using the Rapid Oscillations in the Solar Atmosphere instrument (ROSA) show variations in both cross-sectional area and intensity for magnetic pores in the photosphere. Aims: We study the phase behaviour between cross-sectional area and intensity variations for sausage modes in a photospheric context. We aim to determine the wave mode by looking at the phase difference between the cross-sectional area and intensity variations. Methods: We used a straight cylinder as a model for the flux tube. The plasma is uniform both inside and outside the flux tube with a possible jump in the equilibrium values at the boundary, the magnetic field is directed along the flux tube. We derived analytic expressions for the cross-sectional area variation and the total intensity variation. Using these analytic expressions, we calculated the phase differences between the cross-sectional area and the intensity variations. These phase differences were then used to identify the wave mode. Results: We found that for slow sausage modes the cross-sectional area and intensity variations are always in phase, while for fast sausage modes the variations are in antiphase. Appendix A is available in electronic form at http://www.aanda.org

  12. Krypton charge exchange cross sections for Hall effect thruster models

    SciTech Connect

    Hause, Michael L.; Prince, Benjamin D.; Bemish, Raymond J.

    2013-04-28

    Following discharge from a Hall effect thruster, charge exchange occurs between ions and un-ionized propellant atoms. The low-energy cations produced can disturb operation of onboard instrumentation or the thruster itself. Charge-exchange cross sections for both singly and doubly charged propellant atoms are required to model these interactions. While xenon is the most common propellant currently used in Hall effect thrusters, other propellants are being considered, in particular, krypton. We present here guided-ion beam measurements and comparisons to semiclassical calculations for Kr{sup +} + Kr and Kr{sup 2+} + Kr cross sections. The measurements of symmetric Kr{sup +} + Kr charge exchange are in good agreement with both the calculations including spin-orbit effects and previous measurements. For the symmetric Kr{sup 2+} + Kr reaction, we present cross section measurements for center-of-mass energies between 1 eV and 300 eV, which spans energies not previously examined experimentally. These cross section measurements compare well with a simple one-electron transfer model. Finally, cross sections for the asymmetric Kr{sup 2+} + Kr {yields} Kr{sup +} + Kr{sup +} reaction show an onset near 12 eV, reaching cross sections near constant value of 1.6 A{sup 2} with an exception near 70-80 eV.

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

    NASA Astrophysics Data System (ADS)

    Sofen, E. D.; Evans, M. J.; Lewis, A. C.

    2015-07-01

    Photometric ozone measurements rely upon an accurate value of the ozone absorption cross section at 253.65 nm. This has recently been reevaluated by Viallon et al. (2015) as 1.8 % smaller than the accepted value (Hearn, 1961) used for the preceding fifty 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.

  14. Mental visualization of objects from cross-sectional images

    PubMed Central

    Wu, Bing; Klatzky, Roberta L.; Stetten, George D.

    2011-01-01

    We extended the classic anorthoscopic viewing procedure to test a model of visualization of 3D structures from 2D cross-sections. Four experiments were conducted to examine key processes described in the model, localizing cross-sections within a common frame of reference and spatiotemporal integration of cross sections into a hierarchical object representation. Participants used a hand-held device to reveal a hidden object as a sequence of cross-sectional images. The process of localization was manipulated by contrasting two displays, in-situ vs. ex-situ, which differed in whether cross sections were presented at their source locations or displaced to a remote screen. The process of integration was manipulated by varying the structural complexity of target objects and their components. Experiments 1 and 2 demonstrated visualization of 2D and 3D line-segment objects and verified predictions about display and complexity effects. In Experiments 3 and 4, the visualized forms were familiar letters and numbers. Errors and orientation effects showed that displacing cross-sectional images to a remote display (ex-situ viewing) impeded the ability to determine spatial relationships among pattern components, a failure of integration at the object level. PMID:22217386

  15. Thermoelastic damping in microrings with circular cross-section

    NASA Astrophysics Data System (ADS)

    Li, Pu; Fang, Yuming; Zhang, Jianrun

    2016-01-01

    Predicting thermoelastic damping (TED) is crucial in the design of high Q micro-resonators. Microrings are often critical components in many micro-resonators. Some analytical models for TED in microrings have already been developed in the past. However, the previous works are limited to the microrings with rectangular cross-section. The temperature field in the rectangular cross-section is one-dimensional. This paper deals with TED in the microrings with circular cross-section. The temperature field in the circular cross-section is two-dimensional. This paper first presents a 2-D analytical model for TED in the microrings with circular cross-section. Only the two-dimensional heat conduction in the circular cross-section is considered. The heat conduction along the circumferential direction of the microring is neglected in the 2-D model. Then the 2-D model has been extended to cover the circumferential heat conduction, and a 3-D analytical model for TED has been developed. The analytical results from the present 2-D and 3-D models show good agreement with the numerical results of FEM model. The limitations of the present 2-D analytical model are assessed.

  16. Photodissociation cross section of ClOOCl at 330 nm.

    PubMed

    Jin, Bing; Chen, I-Cheng; Huang, Wen-Tsung; Lien, Chien-Yu; Guchhait, Nikhil; Lin, Jim J

    2010-04-15

    The photolysis rate of ClOOCl is crucial in the catalytic destruction of polar stratospheric ozone. In this work, we determined the photodissociation cross section of ClOOCl at 330 nm with a molecular beam and with mass-resolved detection. The photodissociation cross section is the product of the absorption cross section and the dissociation quantum yield. We formed an effusive molecular beam of ClOOCl at a nozzle temperature of 200 or 250 K and determined its photodissociation probability by measuring the decrease of the ClOOCl intensity upon laser irradiation. By comparing with a reference molecule (Cl(2)), of which the absorption cross section and dissociation quantum yield are well-known, we determined the absolute photodissociation cross section of ClOOCl at 330 nm to be (2.31 +/- 0.11) x 10(-19) cm(2) at 200 K and (2.47 +/- 0.12) x 10(-19) cm(2) at 250 K. Impurity interference has been a well-recognized problem in conventional spectroscopic studies of ClOOCl; our mass-resolved measurement directly overcomes such a problem. This measurement of the ClOOCl photolysis cross section at 330 nm is particularly useful in constraining its atmospheric photolysis rate, which in the polar stratosphere peaks near this wavelength. PMID:20085296

  17. Studies of 54,56Fe Neutron Scattering Cross Sections

    NASA Astrophysics Data System (ADS)

    Hicks, S. F.; Vanhoy, J. R.; French, A. J.; Henderson, S. L.; Howard, T. J.; Pecha, R. L.; Santonil, Z. C.; Crider, B. P.; Liu, S.; McEllistrem, M. T.; Peters, E. E.; Prados-Estévez, F. M.; Ross, T. J.; Yates, S. W.

    2015-05-01

    Elastic and inelastic neutron scattering differential cross sections and ?-ray production cross sections have been measured on 54,56Fe at several incident energies in the fast neutron region between 1.5 and 4.7 MeV. All measurements were completed at the University of Kentucky Accelerator Laboratory (UKAL) using a 7-MV Model CN Van de Graaff accelerator, along with the neutron production and neutron and ?-ray detection systems located there. The facilities at UKAL allow the investigation of both elastic and inelastic scattering with nearly mono-energetic incident neutrons. Time-of-flight techniques were used to detect the scattered neutrons for the differential cross section measurements. The measured cross sections are important for fission reactor applications and also for testing global model calculations such as those found at ENDF, since describing both the elastic and inelastic scattering is important for determining the direct and compound components of the scattering mechanism. The ?-ray production cross sections are used to determine cross sections to unresolved levels in the neutron scattering experiments. Results from our measurements and comparisons to model calculations are presented.

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

    USGS Publications Warehouse

    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.

  19. A coupled-cluster study of photodetachment cross sections of closed-shell anions

    NASA Astrophysics Data System (ADS)

    Cukras, Janusz; Decleva, Piero; Coriani, Sonia

    2014-11-01

    We investigate the performance of Stieltjes Imaging applied to Lanczos pseudo-spectra generated at the coupled cluster singles and doubles, coupled cluster singles and approximate iterative doubles and coupled cluster singles levels of theory in modeling the photodetachment cross sections of the closed shell anions H-, Li-, Na-, F-, Cl-, and OH-. The accurate description of double excitations is found to play a much more important role than in the case of photoionization of neutral species.

  20. Jet-radius dependence of inclusive-jet cross sections in deep inelastic scattering at HERA

    NASA Astrophysics Data System (ADS)

    Chekanov, S.; Derrick, M.; Magill, S.; Miglioranzi, S.; Musgrave, B.; Nicholass, D.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Jechow, M.; Pavel, N.; Yagües Molina, A. G.; Antonelli, S.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Bindi, M.; Boscherini, D.; Bruni, A.; Bruni, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; De Pasquale, S.; Iacobucci, G.; Margotti, A.; Nania, R.; Polini, A.; Rinaldi, L.; Sartorelli, G.; Zichichi, A.; Bartsch, D.; Brock, I.; Goers, S.; Hartmann, H.; Hilger, E.; Jakob, H.-P.; Jüngst, M.; Kind, O. M.; Paul, E.; Rautenberg, J.; Renner, R.; Samson, U.; Schönberg, V.; Shehzadi, R.; Wang, M.; Wlasenko, M.; Brook, N. H.; Heath, G. P.; Morris, J. D.; Namsoo, T.; Capua, M.; Fazio, S.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Tassi, E.; Kim, J. Y.; Ma, K. J.; Ibrahim, Z. A.; Kamaluddin, B.; Wan Abdullah, W. A. T.; Ning, Y.; Ren, Z.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Gil, M.; Olkiewicz, K.; Stopa, P.; Zawiejski, L.; Adamczyk, L.; Bo?d, T.; Grabowska-Bo?d, I.; Kisielewska, D.; ?ukasik, J.; Przybycie?, M.; Suszycki, L.; Kota?ski, A.; S?omi?ski, W.; Adler, V.; Behrens, U.; Bloch, I.; Bonato, A.; Borras, K.; Coppola, N.; Fourletova, J.; Geiser, A.; Gladkov, D.; Göttlicher, P.; Gregor, I.; Haas, T.; Hain, W.; Horn, C.; Kahle, B.; Kötz, U.; Kowalski, H.; Lobodzinska, E.; Löhr, B.; Mankel, R.; Melzer-Pellmann, I.-A.; Montanari, A.; Notz, D.; Nuncio-Quiroz, A. E.; Santamarta, R.; Schneekloth, U.; Spiridonov, A.; Stadie, H.; Stösslein, U.; Szuba, D.; Szuba, J.; Theedt, T.; Wolf, G.; Wrona, K.; Youngman, C.; Zeuner, W.; Lohmann, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Pelfer, P. G.; Bamberger, A.; Dobur, D.; Karstens, F.; Vlasov, N. N.; Bussey, P. J.; Doyle, A. T.; Dunne, W.; Ferrando, J.; Saxon, D. H.; Skillicorn, I. O.; Gialas, I.; Gosau, T.; Holm, U.; Klanner, R.; Lohrmann, E.; Salehi, H.; Schleper, P.; Schörner-Sadenius, T.; Sztuk, J.; Wichmann, K.; Wick, K.; Foudas, C.; Fry, C.; Long, K. R.; Tapper, A. D.; Kataoka, M.; Matsumoto, T.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Dossanov, A.; Pokrovskiy, N. S.; Zhautykov, B. O.; Son, D.; de Favereau, J.; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; Jimenez, M.; Labarga, L.; del Peso, J.; Ron, E.; Soares, M.; Terrón, J.; Zambrana, M.; Corriveau, F.; Liu, C.; Walsh, R.; Zhou, C.; Tsurugai, T.; Antonov, A.; Dolgoshein, B. A.; Rubinsky, I.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Gladilin, L. K.; Katkov, I. I.; Khein, L. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Zotkin, D. S.; Zotkin, S. A.; Abt, I.; Büttner, C.; Caldwell, A.; Kollar, D.; Schmidke, W. B.; Sutiak, J.; Grigorescu, G.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Pellegrino, A.; Tiecke, H.; Vázquez, M.; Wiggers, L.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Lee, A.; Ling, T. Y.; Allfrey, P. D.; Bell, M. A.; Cooper-Sarkar, A. M.; Cottrell, A.; Devenish, R. C. E.; Foster, B.; Korcsak-Gorzo, K.; Patel, S.; Roberfroid, V.; Robertson, A.; Straub, P. B.; Uribe-Estrada, C.; Walczak, R.; Bellan, P.; Bertolin, A.; Brugnera, R.; Carlin, R.; Ciesielski, R.; Dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Stanco, L.; Turcato, M.; Oh, B. Y.; Raval, A.; Ukleja, J.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cole, J. E.; Hart, J. C.; Abramowicz, H.; Gabareen, A.; Ingbir, R.; Kananov, S.; Levy, A.; Kuze, M.; Hori, R.; Kagawa, S.; Okazaki, N.; Shimizu, S.; Tawara, T.; Hamatsu, R.; Kaji, H.; Kitamura, S.; Ota, O.; Ri, Y. D.; Ferrero, M. I.; Monaco, V.; Sacchi, R.; Solano, A.; Arneodo, M.; Ruspa, M.; Fourletov, S.; Martin, J. F.; Boutle, S. K.; Butterworth, J. M.; Gwenlan, C.; Jones, T. W.; Loizides, J. H.; Sutton, M. R.; Targett-Adams, C.; Wing, M.; Brzozowska, B.; Ciborowski, J.; Grzelak, G.; Kulinski, P.; ?u?niak, P.; Malka, J.; Nowak, R. J.; Pawlak, J. M.; Tymieniecka, T.; Ukleja, A.; ?arnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Giller, I.; Hochman, D.; Karshon, U.; Rosin, M.; Brownson, E.; Danielson, T.; Everett, A.; Kçira, D.; Reeder, D. D.; Ryan, P.; Savin, A. A.; Smith, W. H.; Wolfe, H.; Bhadra, S.; Catterall, C. D.; Cui, Y.; Hartner, G.; Menary, S.; Noor, U.; Standage, J.; Whyte, J.; ZEUS Collaboration

    2007-05-01

    Differential inclusive-jet cross sections have been measured for different jet radii in neutral current deep inelastic ep scattering for boson virtualities Q2 > 125 GeV2 with the ZEUS detector at HERA using an integrated luminosity of 81.7 pb-1. Jets were identified in the Breit frame using the kT cluster algorithm in the longitudinally inclusive mode for different values of the jet radius R. Differential cross sections are presented as functions of Q2 and the jet transverse energy, ET,Bjet. The dependence on R of the inclusive-jet cross section has been measured for Q2 > 125 and 500 GeV2 and found to be linear with R in the range studied. Next-to-leading-order QCD calculations give a good description of the measurements for 0.5 ? R ? 1. A value of ?s (MZ) has been extracted from the measurements of the inclusive-jet cross section d? / dQ2 with R = 1 for Q2 > 500 GeV2: ?s (MZ) = 0.1207 ± 0.0014 (stat .)-0.0033+0.0035 (exp .) -0.0023 +0.0022 (th .). The variation of ?s with ET,Bjet is in a good agreement with the running of ?s as predicted by QCD.

  1. Health promoting Behaviors Among Adolescents: A Cross-sectional Study

    PubMed Central

    Musavian, Azra Sadat; Pasha, Afsaneh; Rahebi, Seyyedeh-Marzeyeh; Atrkar Roushan, Zahra; Ghanbari, Atefeh

    2014-01-01

    Background: Health maintenance and promotion are the fundamental prerequisites to community development. The best time for establishing healthy lifestyle habits is during adolescence. Objectives: Due to importance of health promotion behaviors in adolescents, this study was conducted to investigate health-promoting behaviors and its associated factors among high school students in Rasht, Iran. Materials and Methods: A cross-sectional descriptive study was conducted on 424 students during the first semester of the year 2012. We employed the multistage sampling design to recruit from private and public high schools in Rasht, Iran. The data collection instrument was a self-report questionnaire consisting of two parts. The first part of instrument was consisted of demographic questionnaire and the second part was adolescent health promotion scale (AHPS) questionnaire. AHPS questionnaire was consisted of six dimensions (nutrition, social support, health responsibility, life appreciation, physical activity, and stress management) to measure health promoting lifestyles. Statistical analysis was performed by SPSS 16 software employing ANOVA (analysis of variance) test, t-test, Mann-Whitney, and the Kruskal-Wallis. Results: The score of total Adolescent Health Promotion Scale were 3.58 ± 0.52 (possible range was 1-5). The highest score was in life appreciation dimension (3.99 ± 0.068) and the lowest score was in health responsibility dimension. Moreover, Significant associations were found between the adolescent health promotion Scale with age (P < 0.001), gender (P < 0.003), school grade (P < 0.011), father’s educational level (P < 0.045), mother’s educational level (P < 0.021), and mother’s occupation (P < 0.008). Conclusions: Female and older students are at higher risk of developing unhealthy lifestyle. Consequently, healthcare providers, health instructors, schoolteachers, and families must pay more attention to these students. Moreover, as most of lifelong healthy and unhealthy lifestyle habits are established during adolescence, developing effective health promotion and disease prevention strategies for adolescents seems crucial. PMID:25414892

  2. ACTIV87: Fast Neutron Activation Cross Section File

    Energy Science and Technology Software Center (ESTSC)

    1993-08-01

    4. HISTORICAL BACKGROUND AND INFORMATION ACTIV87 is a compilation of fast neutron induced activation reaction cross-sections. The compilation covers energies from threshold to 20 MeV and is based on evaluated data taken from other evaluated data libraries and individual evaluations. The majority of these evaluations were performed by using available experimental data. The aforementioned available experimental data were used in the selection of needed parameters for theoretical computations and for normalizing the results of suchmore »computations. Theoretical calculations were also used for interpolation and extrapolation of experimental cross-section data. All of the evaluated data curves were compared with experimental data that had been reported over the four year period preceding 1987. Only those cross-sections not in contradiction with experimental data that was current in 1987 were retained in the activation file, ACTIV87. In cases of several conflicting evaluations, that evaluation was chosen which best corresponded to the experimental data. A few evaluated curves were renormalized in accordance with the results of the latest precision measurements. 5. APPLICATION OF THE DATA 6. SOURCE AND SCOPE OF DATA The following libraries and individual files of evaluated neutron cross-section data were used for the selection of the activation cross-sections: the BOSPOR Library, the Activation File of the Evaluated Nuclear Data Library, the Evaluated Neutron Data File (ENDF/B-V) Activation File, the International Reactor Dosimetry File (IRDF-82), and individual evaluations carried out under various IAEA research contracts. The file of selected reactions contains 206 evaluated cross-section curves of the (n,2n), (n,p) and (n,a) reactions which lead to radioactive products and may be used in many practical applications of neutron activation analysis. Some competing activation reactions, usually with low cross-section values, are given for completeness.« less

  3. Froissart bound on inelastic cross section without unknown constants

    NASA Astrophysics Data System (ADS)

    Martin, André; Roy, S. M.

    2015-04-01

    Assuming that axiomatic local field theory results hold for hadron scattering, André Martin and S. M. Roy recently obtained absolute bounds on the D wave below threshold for pion-pion scattering and thereby determined the scale of the logarithm in the Froissart bound on total cross sections in terms of pion mass only. Previously, Martin proved a rigorous upper bound on the inelastic cross-section ?inel which is one-fourth of the corresponding upper bound on ?tot, and Wu, Martin, Roy and Singh improved the bound by adding the constraint of a given ?tot. Here we use unitarity and analyticity to determine, without any high-energy approximation, upper bounds on energy-averaged inelastic cross sections in terms of low-energy data in the crossed channel. These are Froissart-type bounds without any unknown coefficient or unknown scale factors and can be tested experimentally. Alternatively, their asymptotic forms, together with the Martin-Roy absolute bounds on pion-pion D waves below threshold, yield absolute bounds on energy-averaged inelastic cross sections. For example, for ?0?0 scattering, defining ?inel=?tot-(??0?0??0?0+??0?0??+?-) , we show that for c.m. energy ?{s }??, ?¯ inel(s ,?)?s ?s?d s'?inel(s')/s'2?(? /4 )(m?)-2[ln (s /s1)+(1 /2 )ln ln (s /s1)+1 ]2 where 1 /s1=34 ? ?{2 ? }m?-2 . This bound is asymptotically one-fourth of the corresponding Martin-Roy bound on the total cross section, and the scale factor s1 is one-fourth of the scale factor in the total cross section bound. The average over the interval (s,2s) of the inelastic ?0?0 cross section has a bound of the same form with 1 /s1 replaced by 1 /s2=2 /s1.

  4. Cross-section Trichometry: A Clinical Tool for Assessing the Progression and Treatment Response of Alopecia

    PubMed Central

    Wikramanayake, Tongyu Cao; Mauro, Lucia M; Tabas, Irene A; Chen, Anne L; Llanes, Isabel C; Jimenez, Joaquin J

    2012-01-01

    Background: To properly assess the progression and treatment response of alopecia, one must measure the changes in hair mass, which is influenced by both the density and diameter of hair. Unfortunately, a convenient device for hair mass evaluation had not been available to dermatologists until the recent introduction of the cross-section trichometer, which directly measures the cross-sectional area of an isolated bundle of hair. Objective: We sought to evaluate the accuracy and sensitivity of the HairCheck® device, a commercial product derived from the original cross-section trichometer. Materials and Methods: Bundles of surgical silk and human hair were used to evaluate the ability of the HairCheck® device to detect and measure small changes in the number and diameter of strands, and bundle weight. Results: Strong correlations were observed between the bundle's cross-sectional area, displayed as the numeric Hair Mass Index (HMI), the number of strands, the silk/hair diameter, and the bundle dry weight. Conclusion: HMI strongly correlated with the number and diameter of silk/hair, and the weight of the bundle, suggesting that it can serve as a valid indicator of hair mass. We have given the name cross-section trichometry (CST) to the methodology of obtaining the HMI using the HairCheck® system. CST is a simple modality for the quantification of hair mass, and may be used as a convenient and useful tool to clinically assess changes in hair mass caused by thinning, shedding, breakage, or growth in males and females with progressive alopecia or those receiving alopecia treatment. PMID:23766610

  5. Numerical analysis of flows of rarefied gases in long channels with octagonal cross section shapes

    SciTech Connect

    Szalmas, L.

    2014-12-09

    Isothermal, pressure driven rarefied gas flows through long channels with octagonal cross section shapes are analyzed computationally. The capillary is between inlet and outlet reservoirs. The cross section is constant along the axial direction. The boundary condition at the solid-gas interface is assumed to be diffuse reflection. Since the channel is long, the gaseous velocity is small compared to the average molecular speed. Consequently, a linearized description can be used. The flow is described by the linearized Bhatnagar-Gross-Krook kinetic model. The solution of the problem is divided into two stages. First, the local flow field is determined by assuming the local pressure gradient. Secondly, the global flow behavior is deduced by the consideration of the conservation of the mass along the axis of the capillary. The kinetic equation is solved by the discrete velocity method on the cross section. Both spatial and velocity spaces are discretized. A body fitted rectangular grid is used for the spatial space. Near the boundary, first-order, while in the interior part of the flow domain, second-order finite-differences are applied to approximate the spatial derivatives. This combination results into an efficient and straightforward numerical treatment. The velocity space is represented by a Gauss-Legendre quadrature. The kinetic equation is solved in an iterative manner. The local dimensionless flow rate is calculated and tabulated for a wide range of the gaseous rarefaction for octagonal cross sections with various geometrical parameters. It exhibits the Knudsen minimum phenomenon. The flow rates in the octagonal channel are compared to those through capillaries with circular and square cross sections. Typical velocity profiles are also shown. The mass flow rate and the distribution of the pressure are determined and presented for global pressure driven flows.

  6. Simulation of multistatic and backscattering cross sections for airborne radar

    NASA Astrophysics Data System (ADS)

    Biggs, Albert W.

    1986-07-01

    In order to determine susceptibilities of airborne radar to electronic countermeasures and electronic counter-countermeasures simulations of multistatic and backscattering cross sections were developed as digital modules in the form of algorithms. Cross section algorithms are described for prolate (cigar shape) and oblate (disk shape) spheroids. Backscattering cross section algorithms are also described for different categories of terrain. Backscattering cross section computer programs were written for terrain categorized as vegetation, sea ice, glacial ice, geological (rocks, sand, hills, etc.), oceans, man-made structures, and water bodies. PROGRAM SIGTERRA is a file for backscattering cross section modules of terrain (TERRA) such as vegetation (AGCROP), oceans (OCEAN), Arctic sea ice (SEAICE), glacial snow (GLASNO), geological structures (GEOL), man-made structures (MAMMAD), or water bodies (WATER). AGCROP describes agricultural crops, trees or forests, prairies or grassland, and shrubs or bush cover. OCEAN has the SLAR or SAR looking downwind, upwind, and crosswind at the ocean surface. SEAICE looks at winter ice and old or polar ice. GLASNO is divided into a glacial ice and snow or snowfields. MANMAD includes buildings, houses, roads, railroad tracks, airfields and hangars, telephone and power lines, barges, trucks, trains, and automobiles. WATER has lakes, rivers, canals, and swamps. PROGRAM SIGAIR is a similar file for airborne targets such as prolate and oblate spheroids.

  7. Cross Sections and Transport Properties of BR- Ions in AR

    NASA Astrophysics Data System (ADS)

    Jovanovic, Jasmina; Stojanovic, Vladimir; Raspopovic, Zoran; Petrovic, Zoran

    2014-10-01

    We have used a combination of a simple semi-analytic theory - Momentum Transfer Theory (MTT) and exact Monte Carlo (MC) simulations to develop Br- in Ar momentum transfer cross section based on the available data for reduced mobility at the temperature T = 300 K over the range 10 Td <= E / N <= 300 Td. At very low energies, we have extrapolated obtained cross sections towards Langevin's cross section. Also, we have extrapolated data to somewhat higher energies based on behavior of similar ions in similar gases and by the addition of the total detachment cross section that was used from the threshold around 7.7 eV. Relatively complete set was derived which can be used in modeling of plasmas by both hybrid, particle in cell (PIC) and fluid codes. A good agreement between calculated and measured ion mobilities and longitudinal diffusion coefficients is an independent proof of the validity of the cross sections that were derived for the negative ion mobility data. In addition to transport coefficients we have also calculated the net rate coefficients of elastic scattering and detachment. Author acknowledge Ministry of Education, Science and Technology, Proj. Nos. 171037 and 410011.

  8. Experience With the SCALE Criticality Safety Cross Section Libraries

    SciTech Connect

    Bowman, S.M.

    2000-08-21

    This report provides detailed information on the SCALE criticality safety cross-section libraries. Areas covered include the origins of the libraries, the data on which they are based, how they were generated, past experience and validations, and performance comparisons with measured critical experiments and numerical benchmarks. The performance of the SCALE criticality safety cross-section libraries on various types of fissile systems are examined in detail. Most of the performance areas are demonstrated by examining the performance of the libraries vs critical experiments to show general trends and weaknesses. In areas where directly applicable critical experiments do not exist, performance is examined based on the general knowledge of the strengths and weaknesses of the cross sections. In this case, the experience in the use of the cross sections and comparisons with the results of other libraries on the same systems are relied on for establishing acceptability of application of a particular SCALE library to a particular fissile system. This report should aid in establishing when a SCALE cross-section library would be expected to perform acceptably and where there are known or suspected deficiencies that would cause the calculations to be less reliable. To determine the acceptability of a library for a particular application, the calculational bias of the library should be established by directly applicable critical experiments.

  9. Electromagnetic Dissociation Cross Sections using Weisskopf-Ewing Theory

    NASA Technical Reports Server (NTRS)

    Adamczyk, Anne M.; Norbury, John W.

    2011-01-01

    It is important that accurate estimates of crew exposure to radiation are obtained for future long-term space missions. Presently, several space radiation transport codes exist to predict the radiation environment, all of which take as input particle interaction cross sections that describe the nuclear interactions between the particles and the shielding material. The space radiation transport code HZETRN uses the nuclear fragmentation model NUCFRG2 to calculate Electromagnetic Dissociation (EMD) cross sections. Currently, NUCFRG2 employs energy independent branching ratios to calculate these cross sections. Using Weisskopf-Ewing (WE) theory to calculate branching ratios, however, is more advantageous than the method currently employed in NUCFRG2. The WE theory can calculate not only neutron and proton emission, as in the energy independent branching ratio formalism used in NUCFRG2, but also deuteron, triton, helion, and alpha particle emission. These particles can contribute significantly to total exposure estimates. In this work, photonuclear cross sections are calculated using WE theory and the energy independent branching ratios used in NUCFRG2 and then compared to experimental data. It is found that the WE theory gives comparable, but mainly better agreement with data than the energy independent branching ratio. Furthermore, EMD cross sections for single neutron, proton, and alpha particle removal are calculated using WE theory and an energy independent branching ratio used in NUCFRG2 and compared to experimental data.

  10. Beam lifetimes and ionization cross sections of U28+

    NASA Astrophysics Data System (ADS)

    Weber, G.; Omet, C.; Dubois, R. D.; de Lucio, O.; Stöhlker, Th.; Brandau, C.; Gumberidze, A.; Hagmann, S.; Hess, S.; Kozhuharov, C.; Reuschl, R.; Spiller, P.; Spillmann, U.; Steck, M.; Thomason, M.; Trotsenko, S.

    2009-08-01

    Beam lifetimes of stored U28+ ions with energies between 10 and 180MeV/u were measured in the heavy ion synchrotron SIS18 and in the experimental storage ring (ESR) of the GSI accelerator facility. By using the internal gas jet target of the ESR, it was possible to obtain projectile ionization cross sections for collisions with H2 and N2 from the lifetime data. The experimental cross sections are compared to theoretical data predicted by the n-body classical-trajectory Monte Carlo (CTMC) method of Olson et al. and to calculations of Shevelko et al. using the LOSS-R code. In addition, both theoretical approaches are probed by using the resulting cross sections as input parameters for the STRAHLSIM code, which models the beam losses and, consequently, the lifetimes in the heavy ion synchrotron SIS18. Both the cross section measurement and the SIS18 lifetime study indicate that the LOSS-R code cross sections are in better agreement with the experimental results than the n-body CTMC calculations.

  11. Absolute cross sections for electron scattering from furan

    NASA Astrophysics Data System (ADS)

    Maljkovi?, J. B.; Blanco, F.; ?urík, R.; García, G.; Marinkovi?, B. P.; Milosavljevi?, A. R.

    2012-08-01

    We report results of measurements and calculations of absolute cross sections for electron scattering from furan molecules (C4H4O). The experimental absolute differential cross sections (DCSs) for elastic electron scattering were obtained for the incident energies from 50 eV to 300 eV and for scattering angles from 20° to 110°, by using a crossed electron-target beam setup and the relative flow technique for calibration to the absolute scale. The calculations of the electron interaction cross sections are based on a corrected form of the independent-atom method, known as the screening corrected additivity rule (SCAR) procedure and using an improved quasifree absorption model. The latter calculations also account for rotational excitations in the approximation of a free electric dipole and were used to obtain elastic DCSs as well as total and integral elastic cross sections which are tabulated in the energy range from 10 to 10 000 eV. All SCAR calculated cross sections agree very well with both the present and previously published experimental results. Additionally, calculations based on the first Born approximation were performed to calculate both elastic and vibrationally inelastic DCSs for all the modes of furane, in the energy range from 50 eV to 300 eV. The ratios of the summed vibrational to elastic DCSs are presented and discussed. Finally, the present results for furan are compared with previously published elastic DCSs for the tetrahydrofuran molecule and discussed.

  12. Polarized single-mode condition for SOI rib waveguide with large cross section

    NASA Astrophysics Data System (ADS)

    Yuan, Dengpeng; Dong, Ying; Liu, Yujin; Li, Tianjian; Zhang, Xudong; Tan, Yushan

    2015-08-01

    In this paper the single mode condition of silicon-on-insulator (SOI) rib waveguide with large cross section is investigated based on the effective index method (EIM) by using numerical computation and analytical derivation with the consideration of the polarization effects. A polarized single-mode condition for SOI rib waveguide with large cross section is presented, the results from analytical derivation are highly concordant with that from numerical computation. For the vertical single-mode condition, the deviations between HE and EH modes correlate oppositely with the total rib height of rib waveguide, and the critical rib height ratio gradually approaches but never equals to 0.5 with the increase of the total rib height. There, HE mode and EH mode are commonly known as quasi-transverse-electric (TE) mode and quasi-transverse-magnetic (TM) mode respectively. The deviation of the critical rib width between HE and EH modes for the lateral single-mode condition is relatively small, which is a function of the rib height ratio but irrelevant to the total rib height for the specified index profile. The fact that the total rib height, index profile, and polarization of modes have effects on the single-mode condition of SOI rib waveguide with large cross section was demonstrated in this work, which was not discussed in the previous works. The results in this work can give guidance to design, simulation and fabrication of SOI rib waveguide with large cross section in practical applications.

  13. Activation energy and capture cross section of majority carrier traps in Zn doped InP

    NASA Technical Reports Server (NTRS)

    Rybicki, George; Williams, Wendell

    1993-01-01

    Schottky barrier diodes were fabricated on Zn doped InP Wafers. The diodes were radiation damaged with 2 MeV protons to a dose of 2 x 10(exp 12)cm(sup -2). The damage was analyzed by DLTS (deep level transient spectroscopy) using the double correlation technique. Capture cross sections were measured directly. Two major defects were observed in the DLTS spectra. The first defect, was H4 at Ev + 0.29 eV, with capture cross section 1.1 x 10(exp -17)cm(sup 2). The second defect, was H5 at Ev + 0.53 eV. Its capture cross section varied with temperature as described by the relationship sigma = sigma(sub 0) exp(delta(E)/kT) where sigma(sub 0) = 1.3 x 10(exp -19)cm(sup 2) and delta(E) = .08 eV. This relationship yields a sigma of 5.9 x 10(exp -21)cm(sup 2) at room temperature. The surprisingly small capture cross section of H5 and its temperature dependence are discussed in terms of the multiphonon emission process for carrier capture at the defect. The advantages of the improved experimental techniques used are also discussed.

  14. Stimulated emission cross section at various temperatures based on laser performance

    NASA Astrophysics Data System (ADS)

    Krishnan, G.; Bidin, N.; Ahmad, M. F. S.; Abdullah, M.

    2015-10-01

    The determination of stimulated emission cross sections at various temperatures is reported. Neodymium doped yttrium orthovanadate crystal (Nd:YVO4) was employed as a gain medium. The temperature of the crystal holder varied between 20 and 60 °C. The cross section was determined based on laser performance. The slope efficiency of the diode end-pumped Nd:YVO4 laser system decreased from 40.2% to 31.7%, while the threshold power increased from 0.744 to 1.028?W. The far-field beam diameter increased linearly with the absorbed pump power at a constant temperature. There was no correlation between the rate of change of the beam diameter with temperature due to mechanical stress fluctuation. The stimulated emission cross section was found to decrease at a rate of??-0.45% °C-1, which concurs with previous works. The stimulated emission cross section of various solid-state gain mediums can be determined through this method.

  15. Detection and interpretation of ocean roughness variations across the Gulf Stream inferred from radar cross section observations

    NASA Technical Reports Server (NTRS)

    Weissman, D. E.; Thompson, T. W.

    1977-01-01

    Radar cross section data shows that the Gulf Stream has a higher cross section per unit area (interpreted here as a greater roughness) than the water on the continental shelf. A steep gradient in cross section was often seen at the expected location of the western boundary. There were also longer-scale (10-20 km) gradual fluctuations within the stream of significant magnitude. These roughness variations are correlated with the surface shear stress that the local wind imposes on the sea. Using the available surface-truth information concerning the wind speed and direction, an assumed Gulf Stream velocity profile, and high-resolution ocean-surface temperature data obtained by the VHRR onboard a NOAA-NESS polar-orbiting satellite, the present study demonstrates that the computed surface stress variation bears a striking resemblance to the measured radar cross-section variations.

  16. Mean field and correlated descriptions of Bose-Einstein condensates

    NASA Astrophysics Data System (ADS)

    Mahmud, Khan W.

    This thesis presents an analysis of Bose-Einstein condensates (BECs) in external traps both within a mean field model and a correlated model. The mean field model described by the nonlinear Schrodinger equation is solved analytically in quasi-one dimension for two ideal trapping potentials: a finite square well and a double square well. For a more complete description of BEC in a double well that captures the phenomenon of fragmentation, a two-mode correlated model is analyzed. Quantum-classical correspondence for the eigenstates and the dynamics is demonstrated in phase space. A phase engineering method is proposed for the generation of tunable entangled number states. The double well analysis is extended to multiple wells demonstrating the generation of multi-positional entangled number states. An application of the double well entangled states in Heisenberg limited interferometry is explored.

  17. Testing wave packet dynamics in computing radiative association cross sections

    NASA Astrophysics Data System (ADS)

    Martinazzo, Rocco; Tantardini, Gian Franco

    2005-03-01

    A time-dependent wave packet method is used to compute cross sections for radiative recombination reactions using the Li(S2)+H+ ?LiH+(X?+2)+? as a test case. Cross sections are calculated through standard time-to-energy mapping of the time-dependent transition moment and a useful method is introduced to deal with the low collision energy regime. Results are in quantitative agreement over the whole energy range 10-4-5eV with previous time-independent results for the same system [I. Baccarelli, L. Andric, T. Grozdanov, and R. McCarroll, J. Chem. Phys. 117, 3013 (2002)], thereby suggesting that the method can be of help in computing radiative association cross sections for more complicated systems.

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

    E-print Network

    John W. Norbury; Lawrence W. Townsend

    2006-12-18

    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 $(A_PA_T)^{2/3}$, 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.

  19. pi+- p differential cross sections at low energies

    E-print Network

    H. Denz; P. Amaudruz; J. T. Brack; J. Breitschopf; P. Camerini; J. L. Clark; H. Clement; L. Felawka; E. Fragiacomo; E. F. Gibson; N. Grion; G. J. Hofman; B. Jamieson; E. L. Mathie; R. Meier; G. Moloney; D. Ottewell; O. Patarakin; J. D. Patterson; M. M. Pavan; S. Piano; K. Raywood; R. A. Ristinen; R. Rui; M. E. Sevior; G. R. Smith; J. Stahov; R. Tacik; G. J. Wagner; F. von Wrochem; D. M. Yeomans

    2005-12-03

    Differential cross sections for pi- p and pi+ p elastic scattering were measured at five energies between 19.9 and 43.3 MeV. The use of the CHAOS magnetic spectrometer at TRIUMF, supplemented by a range telescope for muon background suppression, provided simultaneous coverage of a large part of the full angular range, thus allowing very precise relative cross section measurements. The absolute normalisation was determined with a typical accuracy of 5 %. This was verified in a simultaneous measurement of muon proton elastic scattering. The measured cross sections show some deviations from phase shift analysis predictions, in particular at large angles and low energies. From the new data we determine the real part of the isospin forward scattering amplitude.

  20. Neutron Capture Cross Section Calculations with the Statistical Model

    NASA Astrophysics Data System (ADS)

    Beard, Mary; Uberseder, Ethan; Wiescher, Michael

    2014-09-01

    Hauser-Feshbach (HF) cross sections are of enormous importance for a wide range of applications, from waste transmutation and nuclear technologies, to medical applications, and nuclear astrophysics. It is a well observed result that different nuclear input models sensitively affect HF cross section calculations. Less well-known however are the effects on calculations originating from model-specific implementation details (such as level density parameter, matching energy, backshift and giant dipole parameters), as well as effects from non-model aspects, such as experimental data truncation and transmission function energy binning. To investigate the effects or these various aspects, Maxwellian-averaged neutron capture cross sections have been calculated for approximately 340 nuclei. The relative effects of these model details will be discussed.

  1. NC515: a new dipole cross-section for SSC

    SciTech Connect

    Caspi, S.; Helm, M.; Laslett, L.J.; Taylor, C.

    1986-01-01

    A new dipole cross-section for SSC is outlined which has multipole coefficients of less than 1.0 x 10/sup -6/ of the dipole field (or 0.01 units) at 1.0 cm. This cross-section has four conductor blocks (three wedges, sixteen turns) in the inner layer and tow conductor blocks (one wedge, twenty turns) in the outer layer. The two layers were formed from the same types of ''partially-keystoned'' cable used in model magnets at LBL and BNL. Based on present cable design an operating field of 6.6 T at 4.34 K is chosen. The new cross-section ''NC515'' and multipoles (for ..mu..-infinite in iron) are shown.

  2. Neutron Cross Section Evaluation of Tungsten and Tantalum

    NASA Astrophysics Data System (ADS)

    Kim, H. I.; Lee, C. W.; Kim, D. H.; Lee, Y.-O.

    2014-04-01

    The evaluations of neutron cross sections and covariances are presented for tungsten and tantalum which are considered as a prime candidate of plasma facing materials in fusion reactors and/or a structural material of the Korea Helium Cooled Ceramic Reflector (Ko HCCR) Test Blanket Module (TBM). The Fusion Evaluated Nuclear Data Library (FENDL-2.1) has been employed as the nuclear data for the neutronics analysis to obtain the optimal design parameters for Ko HCCR TBM. However, the neutron cross sections and energy and/or angular dependent neutron spectra from FENDL-2.1 showed some discrepancies with the differential and integral measured data available for tungsten and tantalum. In response to these situations, the neutron cross section for 181Ta and 180,182,183,184,186W have been newly evaluated using the up-to-date nuclear reaction code and the measured data available.

  3. Inelastic cross sections for positron scattering from atomic hydrogen

    SciTech Connect

    Weber, M.; Hofmann, A.; Raith, W.; Sperber, W.; Jacobsen, F.; Lynn, K.G.

    1994-12-31

    Positronium formation (Ps) cross sections for positrons impinging on atomic hydrogen were measured in the impact energy range from 13eV to 255eV at the High Intensity Positron (HIP) beam at Brookhaven National Laboratory (BNL). The Ps-formation cross section was found to rise rapidly from the threshold at 6.8eV to a maximum value of (2.98 {plus_minus} 0.18) {times} 10{sup {minus}16} cm{sup 2} for {approx} 15eV positrons. By 75eV it drops below the detection limit of 0.17 {times} 10{sup {minus}16} cm{sup 2} which is the present level of statistical uncertainty. The experiment was modified to enable the measurement of doubly differential scattering cross sections.

  4. Majorana Dark Matter Cross Sections with Nucleons at High Energies

    E-print Network

    Yu Seon Jeong; C. S. Kim; Mary Hall Reno

    2012-10-17

    Non-relativistic dark matter scattering with nucleons is constrained by direct detection experiments. We use the XENON constraints on the spin-independent and spin-dependent cross section for dark matter scattering with nucleons to constrain a hypothetical Majorana fermionic dark matter particle's couplings to the Higgs boson and Z boson. In the procedure we illustrate the change in the dark matter nucleon cross section as one goes from non-relativistic, coherent scattering to relativistic, incoherent scattering. While the Z invisible decay width excludes directly couplings of dark matter to ordinary matter, by introducing a light Z' portal to the dark sector, a relatively large dark matter nucleon cross section can be preserved even with accelerator experiment constraints for dark matter with a mass of ~10 GeV

  5. Pion Total Cross Section in Nucleon - Nucleon Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    2009-01-01

    Total cross section parameterizations for neutral and charged pion production in nucleon - nucleon collisions are compared to experimental data over the projectile momentum range from threshold to 300 GeV. Both proton - proton and proton - neutron reactions are considered. Overall excellent agreement between parameterizations and experiment is found, except for notable disagreements near threshold. In addition, the hypothesis that the neutral pion production cross section can be obtained from the average charged pion cross section is checked. The theoretical formulas presented in the paper obey this hypothesis for projectile momenta below 500 GeV. The results presented provide a test of engineering tools used to calculate the pion component of space radiation.

  6. 63Ni (n ,? ) cross sections measured with DANCE

    NASA Astrophysics Data System (ADS)

    Weigand, M.; Bredeweg, T. A.; Couture, A.; Göbel, K.; Heftrich, T.; Jandel, M.; Käppeler, F.; Lederer, C.; Kivel, N.; Korschinek, G.; Krti?ka, M.; O'Donnell, J. M.; Ostermöller, J.; Plag, R.; Reifarth, R.; Schumann, D.; Ullmann, J. L.; Wallner, A.

    2015-10-01

    The neutron capture cross section of the s -process branch nucleus 63Ni affects the abundances of other nuclei in its region, especially 63Cu and 64Zn. In order to determine the energy-dependent neutron capture cross section in the astrophysical energy region, an experiment at the Los Alamos National Laboratory has been performed using the calorimetric 4 ? BaF2 array DANCE. The (n ,? ) cross section of 63Ni has been determined relative to the well-known 197Au standard with uncertainties below 15%. Various 63Ni resonances have been identified based on the Q value. Furthermore, the s -process sensitivity of the new values was analyzed with the new network calculation tool NETZ.

  7. Recent positron-atom cross section measurements and calculations

    NASA Astrophysics Data System (ADS)

    Chiari, Luca; Zecca, Antonio

    2014-10-01

    We review recent cross section results for low-energy positron scattering from atomic targets. A comparison of the latest measurements and calculations for positron collisions with the noble gases and a brief update of the newest studies on other atoms is presented. In particular, we provide an overview of the cross sections for elastic scattering, positronium formation, direct and total ionisation, as well as total scattering, at energies typically between about 0.1 and a few hundred eV. We discuss the differences in the current experimental data sets and compare those results to the available theoretical models. Recommended data sets for the total cross section are also reported for each noble gas. A summary of the recent developments in the scattering from other atoms, such as atomic hydrogen, the alkali and alkaline-earth metals, and two-electron systems is finally provided.

  8. Photoabsorption cross section of acetylene in the EUV region

    NASA Technical Reports Server (NTRS)

    Wu, C. Y. R.; Judge, D. L.

    1985-01-01

    The measurement of the absolute photoabsorption cross sections of C2H2 in the 175-740 A region by means of a double ionization chamber is reported. The continuum background source is the synchrotron radiation emitted by the Wisconsin 240 MeV electron storage ring. It is found that the cross sections range from 2 to a maximum of 36 Mb. Two new Rydberg series are identified and the cross section data are applied in the analysis of various sum rules. From the rules, it is shown that the data of C2H2 in the 580-1088 A range may be too low, while the measured ionization transition moment may be too high.

  9. Assessment of health status of adolescent burn victims undergoing rehabilitation: a cross-sectional field study.

    PubMed

    Nicolosi, Júlia Teixeira; de Carvalho, Viviane Fernandes; Sabatés, Ana Llonch; Paggiaro, André Oliveira

    2013-01-01

    Teenagers may experience physiological and psychological changes when they suffer from a severe burn. The aim of this study was to assess the state of health of teenagers who were undergoing a rehabilitation process following a severe burn. A cross-sectional field study was carried out with 63 teenagers and young adults who had suffered burns. The tests applied were social, demographic, and clinical instruments. The specific tests included the Burn Specific Health Scale-Revised, Beck Depression Inventory, Rosenberg's Self-Esteem Scale, and Functional Independence Measurement. The results were analyzed by using descriptive statistics, multivariate analysis of variance, variance analysis, and Cronbach's reliability analysis. The social and demographic analysis of the population has shown a prevalence of female (60.3%), single subjects (93.7%), and ages between 12 and 20 years (mean age of 15.95 years). The mean total body surface area burn was 23.84%, with accidents as the main causative factor (92.10%). More than half (52.4%) reported functional and aesthetic effects after the burn, with 81% concerned about the visible scar. Cronbach's reliability analysis has shown statistically confident results for all the instruments as applied. The multivariate analysis showed a correlation between the work domain and marital status, whereas there was no evidence to show a correlation between sex, age, physical or aesthetic sequelae or visibility of burns, and depression, self-esteem, functional independence, or current state of health. The results obtained prove the reliability of the instruments applied, making it possible to assess the state of teenagers and young adults health during the rehabilitation process. PMID:24297081

  10. KAP AMONG DOCTORS WORKING IN HOSPITALS, REGARDING HALAL PHARMACEUTICALS; A CROSS SECTIONAL ASSESSMENT.

    PubMed

    Sadeeqa, Saleha; Sarriff, Azmi; Masood, Imran; Atif, Muhammad; Farooqui, Maryam

    2015-01-01

    There is a growing awareness amongst Muslims to avoid all items containing non-Halal ingredients. This sentiment has now progressed into the field of various medications. It therefore, required a study to assess the knowledge, attitude and perception (KAP) relating to pharmaceuticals containing non-Halal ingredients among doctors working in various hospitals of Malaysia. This was a cross sectional study, carried out in January 2013-February 2013 period, using a structured, self-administered questionnaires. Study settings included various government hospitals in Malaysia. Data were collected by distributing questionnaires through respective heads of the departments. Study was conducted on a sample of 243 participants. Inclusion criterion was a registered medical doctor working in a government hospital. Descriptive statistics (mean, standard deviation, frequency, percentage, median, inter quartile range) was applied to summarize the data, non-parametric tests were applied. ?2 Test and Fisher's Exact Test were applied to assess the association between demographic characteristics and knowledge, attitude and perception scores. Results revealed that the hospital doctors had a good and positive attitude and perception about Halal pharmaceuticals. Mean knowledge score out of maximum possible 9 score was 7.67 ± 1.68. Mean attitude score out of maximum possible 45 score was 34.10 ± 5.35 while mean perception score out of maximum possible 55 score was 45.73 ± 5.44. Mean overall KAP score out of maximum possible 109 was 87.60 ± 10.37. There was a significant, positive and weak correlation (0.20-0.29) between knowledge and attitude (r = 0.231, p < 0.001) as well as between knowledge and perception (r = 0.209, p = 0.001) while there was good correlation (0.5-0.75) between attitude and perception (r = 0.588, p < 0.001). It is concluded from the results that the better knowledge the respondents have on Halal pharmaceuticals the better is their perception and attitude towards Halal pharmaceuticals. PMID:26642670

  11. Total cross section of electron scattering by fluorocarbon molecules

    NASA Astrophysics Data System (ADS)

    Yamada, T.; Ushiroda, S.; Kondo, Y.

    2008-12-01

    A compact linear electron transmission apparatus was used for the measurement of the total electron scattering cross section at 4-500 eV. Total cross sections of chlorofluorocarbon (CCl2F2), hydrochlorofluorocarbon (CHClF2), perfluoropropane (C3F8), perfluoro-n-pentane (C5F12), perfluoro-n-hexane (C6F14) and perfluoro-n-octane (C8F18) were obtained experimentally and compared with the values obtained from a theoretical calculation and semi-empirical model calculation.

  12. abo-cross: Hydrogen broadening cross-section calculator

    NASA Astrophysics Data System (ADS)

    Barklem, P. S.; Anstee, S. D.; O'Mara, B. J.

    2015-07-01

    Line broadening cross sections for the broadening of spectral lines by collisions with neutral hydrogen atoms have been tabulated by Anstee & O'Mara (1995), Barklem & O'Mara (1997) and Barklem, O'Mara & Ross (1998) for s-p, p-s, p-d, d-p, d-f and f-d transitions. abo-cross, written in Fortran, interpolates in these tabulations to make these data more accessible to the end user. This code can be incorporated into existing spectrum synthesis programs or used it in a stand-alone mode to compute line broadening cross sections for specific transitions.

  13. Hadronic absorption cross sections of $B_{c}$

    E-print Network

    M. A. K. Lodhi; Faisal Akram; Shaheen Irfan

    2013-09-11

    The cross sections of $B_{c}$\\ absorption by $\\pi $ mesons are calculated using hadronic Lagrangian based on SU(5) flavor symmetry. Calculated cross sections are found to be in range 2 to 7 mb and 0.2 to 2 mb for the processes $B_{c}^{+}\\pi \\rightarrow DB$ and $B_{c}^{+}\\pi \\rightarrow D^{\\ast}B^{\\ast}$ respectively, when the monopole form factor is included. These results could be useful in calculating production rate of $B_{c}$ meson in relativistic heavy ion collisions.

  14. B_{c} absorption cross sections by nucleons

    E-print Network

    Faisal Akram; M. A. K. Lodhi

    2013-09-16

    The cross sections of $B_{c}$\\ absorption by nucleons are calculated in meson-baryon exchange model using hadronic Lagrangian based on SU(4)/SU(5) flavor symmetries. The values of different coupling constants used in the model are obtained from vector meson dominance model, QCD sum rule or SU(4)/SU(5) flavor symmetries. Calculated values of cross sections are found to be significantly different from the previous study in which b-flavored hadron exchange is neglected. These results could be useful in calculating production rate of $B_{c}$ meson in relativistic heavy ion collisions.

  15. Cross section for {sup 246}Cm subbarrier fission

    SciTech Connect

    Alekseev, A. A.; Bergman, A. A.; Berlev, A. I.; Koptelov, E. A.; Samylin, B. F.; Trufanov, A. M.; Fursov, B. I.; Shorin, V. S.

    2010-10-15

    The cross section for {sup 246}Cm fission induced by neutrons of energy in the range 0.1 eV-20 keV was measured by the neutron lead slowing-down spectrometer (LSDS-100) of the Institute for Nuclear Research (INR, Russian Academy of Sciences, Moscow). The parameters of the resonance area and of the fission width were evaluated for several low-lying s-wave neutron resonances. The parameters of the intermediate structure in the cross section for the subbarrier fusion of {sup 246}Cm nuclei were found. The results obtained in this way were compared with available experimental data and with recommended evaluated data.

  16. Cross section for the subbarrier fission of {sup 244}Cm

    SciTech Connect

    Alekseev, A. A.; Bergman, A. A.; Berlev, A. I.; Koptelov, E. A.; Samylin, B. F.; Svirin, M. I.; Trufanov, A. M.; Fursov, B. I.; Shorin, V. S.

    2010-09-15

    The cross section for {sup 244}Cm fission induced by neutrons of energy in the range between 0.07 eV and 20 keV was measured by using the lead slowing-down spectrometer (LSDS-100) of the Institute for Nuclear Research (Russian Academy of Sciences, Moscow). The parameters of the resonance areas were determined for the lowest eight s-wave neutron resonances, and the respective fission widths were evaluated. Also, the parameters of the intermediate structure in the cross section for the subbarrier fission of {sup 244}Cm nuclei were evaluated. The results were compared with available data and recommendations based on evaluations.

  17. Hadronic absorption cross sections of B{sub c}

    SciTech Connect

    Lodhi, M. A. K.; Akram, Faisal; Irfan, Shaheen

    2011-09-15

    The cross sections of B{sub c} absorption by {pi} mesons are calculated using a hadronic Lagrangian based on the SU(5) flavor symmetry. Calculated cross sections are found to be in the ranges 2-7 mb and 0.2-2 mb for the processes B{sub c}{sup +}{pi}{yields}DB and B{sub c}{sup +}{pi}{yields}D*B*, respectively, when the monopole form factor is included. These results could be useful in calculating the production rate of B{sub c} mesons in relativistic heavy ion collisions.

  18. Measurements of multiphoton action cross sections for multiphoton microscopy

    PubMed Central

    Cheng, Li-Chung; Horton, Nicholas G.; Wang, Ke; Chen, Shean-Jen; Xu, Chris

    2014-01-01

    We report quantitative measurements of two-, three-, and four-photon excitation action cross sections of several commonly used fluorophores and fluorescent proteins at three different excitation wavelengths of 800 nm, 1300 nm, and 1680 nm. The measured cross section values are consistent with simple quantum mechanic estimations. These values indicate that the optimum repetition rate for deep tissue 3-photon microscopy is approximately 1 to 2 MHz. We further demonstrate that it is feasible to perform 4-photon fluorescence microscopy of GFP labeled microglia in mouse brain in vivo at 1700 nm. 4-photon excitation increases the accessibility of fluorophores at the long wavelength spectral window of 1700 nm. PMID:25360361

  19. Light ray tracing through a leaf cross section

    NASA Technical Reports Server (NTRS)

    Kumar, R.; Silva, L. F.

    1973-01-01

    A light ray, incident at about 5 deg to the normal, is geometrically plotted through the drawing of the cross section of a soybean leaf using Fresnel's equations and Snell's law. The optical mediums of the leaf considered for ray tracing are: air, cell sap, chloroplast, and cell wall. The ray is also drawn through the same leaf cross section with cell wall and air as the only optical mediums. The values of the reflection and transmission found from the ray tracing tests agree closely with the experimental results obtained using a Beckman Dk-2A Spectroreflector.

  20. Light ray tracing through a leaf cross section

    NASA Technical Reports Server (NTRS)

    Kumar, R.; Silva, L.

    1973-01-01

    A light ray, incident at about 5 deg to the normal, is geometrically plotted through the drawing of the cross section of a soybean leaf using Fresnel's equations and Snell's law. The optical mediums of the leaf considered for ray tracing are air, cell sap, chloroplast, and cell wall. The above ray is also drawn through the same leaf cross section considering cell wall and air as the only optical mediums. The values of the reflection and transmission found from ray tracing agree closely with the experimental results obtained using a Beckman DK-2A spectroreflectometer.

  1. Cross section expansion for direct neutron radiative capture

    SciTech Connect

    Baye, D.

    2004-07-01

    Cross sections for neutron radiative capture multiplied by the relative velocity can be expressed as a Taylor expansion in powers of the relative energy. The coefficients of this expansion are expressed in the potential model as integrals involving solutions of the radial Schroedinger equation and of its inhomogeneous energy derivatives calculated at zero energy. Similarities and differences with charged-particle capture are emphasized. The {sup 12}C(n,{gamma}){sup 13}C capture reaction is treated as an example. The coefficients of the Taylor expansion lead to simple parametrizations of the experimental partial cross sections for neutron capture to each {sup 13}C bound state.

  2. Inclusive charged particle cross sections in photoproduction at HERA

    NASA Astrophysics Data System (ADS)

    Abt, I.; Ahmed, T.; Andreev, V.; Aid, S.; Andrieu, B.; Appuhn, R.-D.; Arpagaus, M.; Babaev, A.; Bärwolff, H.; Bán, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Bassler, U.; Beck, H. P.; Behrend, H.-J.; Belousov, A.; Berger, Ch.; Bergstein, H.; Bernardi, G.; Bernet, R.; Bertrand-Coremans, G.; Besançon, M.; Biddulph, P.; Binder, E.; Bizot, J. C.; Blobel, V.; Borras, K.; Bosetti, P. C.; Boudry, V.; Bourdarios, C.; Braemer, A.; Brasse, F.; Braun, U.; Braunschweig, W.; Brisson, V.; Bruncko, D.; Büngener, L.; Bürger, J.; Büsser, F. W.; Buniatian, A.; Burke, S.; Buschhorn, G.; Campbell, A. J.; Carli, T.; Charles, F.; Chyla, J.; Clarke, D.; Clegg, A. B.; Colombo, M.; Coughlan, J. A.; Courau, A.; Coutures, Ch.; Cozzika, G.; Criegee, L.; Cvach, J.; Dagoret, S.; Dainton, J. B.; Danilov, M.; Dann, A. W. E.; Dau, W. D.; David, M.; Deffur, E.; Delcourt, B.; Del Buono, L.; Devel, M.; De Roeck, A.; Di Nezza, P.; Dingus, P.; Dollfus, C.; Dowell, J. D.; Dreis, H. B.; Drescher, A.; Duboc, J.; Düllmann, D.; Dünger, O.; Duhm, H.; Ebbinghaus, R.; Eberle, M.; Ebert, J.; Ebert, T. R.; Eckerlin, G.; Efremenko, V.; Egli, S.; Ehrlichmann, H.; Eichenberger, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellis, N. N.; Ellison, R. J.; Elsen, E.; Erdmann, M.; Evrard, E.; Favart, L.; Fedotov, A.; Feeken, D.; Felst, R.; Feltesse, J.; Fensome, I. F.; Ferencei, J.; Ferrarotto, F.; Flamm, K.; Flauger, W.; Fleischer, M.; Flieser, M.; Flügge, G.; Fomenko, A.; Fominykh, B.; Forbush, M.; Formánek, J.; Foster, J. M.; Franke, G.; Fretwurst, E.; Fuhrmann, P.; Gabathuler, E.; Gamerdinger, K.; Garvey, J.; Gayler, J.; Gebauer, M.; Gellrich, A.; Gennis, M.; Genzel, H.; Gerhards, R.; Godfrey, L.; Goerlach, U.; Goerlich, L.; Gogitidze, N.; Goldberg, M.; Goldner, D.; Goodall, A. M.; Gorelov, I.; Goritchev, P.; Grab, C.; Grässler, H.; Grässler, R.; Greenshaw, T.; Greif, H.; Grindhammer, G.; Gruber, A.; Gruber, C.; Haack, J.; Haidt, D.; Hajduk, L.; Hamon, O.; Hampel, M.; Hanlon, E. M.; Hapke, M.; Harjes, J.; Haydar, R.; Haynes, W. J.; Heatherington, J.; Hedberg, V.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Herma, R.; Herynek, I.; Hildesheim, W.; Hill, P.; Hilton, C. D.; Hladký, J.; Hoeger, K. C.; Höppner, M.; Huet, Ph.; Hufnagel, H.; Huot, N.; Ibbotson, M.; Itterbeck, H.; Jabiol, M.-A.; Jacholkowska, A.; Jacobsson, C.; Jaffre, M.; Jansen, T.; Jönsson, L.; Johannsen, K.; Johnson, D. P.; Johnson, L.; Jung, H.; Kalmus, P. I. P.; Kant, D.; Kazarian, S.; Kaschowitz, R.; Kasselmann, P.; Kathage, U.; Kaufmann, H. H.; Kenyon, I. R.; Kermiche, S.; Keuker, C.; Kiesling, C.; Klein, M.; Kleinwort, C.; Knies, G.; Ko, W.; Köhler, T.; Kolanoski, H.; Kole, F.; Kolya, S. D.; Korbel, V.; Korn, M.; Kostka, P.; Kotelnikov, S. K.; Krasny, M. W.; Krehbiel, H.; Krücker, D.; Krüger, U.; Kubenka, J. P.; Küster, H.; Kuhlen, M.; Kur?a, T.; Kurzhöfer, J.; Kuznik, B.; Lacour, D.; Lamarche, F.; Lander, R.; Landon, M. P. J.; Lange, W.; Langkau, R.; Lanius, P.; Laporte, J. F.; Lebedev, A.; Leuschner, A.; Leverenz, C.; Levonian, S.; Lewin, D.; Ley, Ch.; Lindner, A.; Lindström, G.; Linsel, F.; Lipinski, J.; Loch, P.; Lohmander, H.; Lopez, G. C.; Lüers, D.; Lüke, D.; Magnussen, N.; Malinovski, E.; Mani, S.; Marage, P.; Marks, J.; Marshall, R.; Martens, J.; Martin, R.; Martyn, H.-U.; Martyniak, J.; Masson, S.; Mavroidis, A.; Maxfiedl, S. J.; McMahon, S. J.; Mehta, A.; Meier, K.; Mercer, D.; Merz, T.; Meyer, C. A.; Meyer, H.; Meyer, J.; Mikocki, S.; Monnier, E.; Moreau, F.; Moreels, J.; Morris, J. V.; Müller, K.; Murín, P.; Murray, S. A.; Nagovizin, V.; Naroska, B.; Naumann, Th.; Newman, P. R.; Newton, D.; Neyret, D.; Nguyen, H. K.; Niebergall, F.; Niebuhr, C.; Nisius, R.; Nowak, G.; Noyes, G. W.; Nyberg, M.; Oberlack, H.; Obrock, U.; Olsson, J. E.; Orenstein, S.; Ould-Saada, F.; Pascaud, C.; Patel, G. D.; Peppel, E.; Peters, S.; Phillips, H. T.; Phillips, J. P.; Pichler, Ch.; Pilgram, W.; Pitzl, D.; Prell, S.; Prosi, R.; Rädel, G.; Raupach, F.; Rauschnabel, K.; Reimer, P.; Reinshagen, S.; Ribarics, P.; Riech, V.; Riedlberger, J.; Riess, S.; Rietz, M.; Robertson, S. M.; Robmann, P.; Roosen, R.; Rosenbauer, K.; Rostovtsev, A.; Royon, C.; Rudowicz, M.; Ruffer, M.; Rusakov, S.; Rybicki, K.; Sahlmann, N.; Sanchez, E.; Sankey, D. P. C.; Savitsky, M.; Schacht, P.; Schleper, P.; von Schlippe, W.; Schmidt, C.; Schmidt, D.; Schmitz, W.; Schöning, A.; Schröder, V.; Schuhmann, E.; Schulz, M.; Schwab, B.; Schwind, A.; Scobel, W.; Seehausen, U.; Sell, R.; Semenov, A.; Shekelyan, V.; Sheviakov, I.; Shooshtari, H.; Shtarkov, L. N.; Siegmon, G.; Siewert, U.; Sirois, Y.; Skillicorn, I. O.; Smirnov, P.; Smith, J. R.; Soloviev, Y.; Spitzer, H.; Steenbock, M.; Steffen, P.; Steinberg, R.; Stella, B.; Stephens, K.; Stier, J.; Stösslein, U.; Strachota, J.; Straumann, U.; Struczinski, W.

    1994-05-01

    Cross sections are presented for the inclusive production of charged particles measured in electron-proton collisions at low Q2 with the H1 detector at HERA. The transverse momentum distribution extends up to 8 GeV/ c. Its shape is found to be harder than that observed in overlinepp collisions at comparable centre-of-mass energies ?S ?p ? ?S overlinepp ? 200 GeV, and also harder than in ?p collisions at lower energies ? S?p ? 18 GeV. Results from quantum chromodynamics (QCD) calculations agree with the measured transverse momentum and pseudorapidity cross sections.

  3. Total photoproduction cross section measurement at HERA energies

    NASA Astrophysics Data System (ADS)

    Ahmed, T.; Andreev, V.; Andrieu, B.; Arpagaus, M.; Babaev, A.; Bärwolff, H.; Bán, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Bassler, U.; Beck, G. A.; Beck, H. P.; Behrend, H.-J.; Belousov, A.; Berger, Ch.; Bergstein, H.; Bernardi, G.; Bernet, R.; Berthon, U.; Bertrand-Coremans, G.; Besançon, M.; Biddulph, P.; Binder, E.; Bizot, J. C.; Blobel, V.; Borras, K.; Bosetti, P. C.; Boudry, V.; Bourdarios, C.; Brasse, F.; Braun, U.; Braunschweig, W.; Brisson, V.; Bruncko, D.; Bürger, J.; Büsser, F. W.; Buniatian, A.; Burke, S.; Buschhorn, G.; Campbell, A. J.; Carli, T.; Charles, F.; Clarke, D.; Clegg, A. B.; Colombo, M.; Coughlan, J. A.; Courau, A.; Coutures, Ch.; Cozzika, G.; Criegee, L.; Cvach, J.; Dainton, J. B.; Danilov, M.; Dann, A. W. E.; Dau, W. D.; David, M.; Deffur, E.; Delcourt, B.; del Buono, L.; Devel, M.; de Roeck, A.; Dingus, P.; Dollfus, C.; Dowell, J. D.; Dreis, H. B.; Drescher, A.; Duboc, J.; Düllmann, D.; Dünger, O.; Duhm, H.; Eberle, M.; Ebert, J.; Ebert, T. R.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichenberger, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellis, N. N.; Ellison, R. J.; Elsen, E.; Erdmann, M.; Evrard, E.; Favart, L.; Fedotov, A.; Feeken, D.; Felst, R.; Feltesse, J.; Feng, Y.; Fensome, I. F.; Ferencei, J.; Ferrarotto, F.; Flauger, W.; Fleischer, M.; Flower, P. S.; Flügge, G.; Fomenko, A.; Fominykh, B.; Forbush, M.; Formánek, J.; Foster, J. M.; Franke, G.; Fretwurst, E.; Fuhrmann, P.; Gabathuler, E.; Gamerdinger, K.; Garvey, J.; Gayler, J.; Gellrich, A.; Gennis, M.; Gensch, U.; Genzel, H.; Gerhards, R.; Gillespie, D.; Godfrey, L.; Goerlach, U.; Goerlich, L.; Goldberg, M.; Goodall, A. M.; Gorelov, I.; Goritchev, P.; Grab, C.; Grässler, H.; Grässler, R.; Greenshaw, T.; Greif, H.; Grindhammer, G.; Gruber, C.; Haack, J.; Haidt, D.; Hajduk, L.; Hamon, O.; Handschuh, D.; Hanlon, E. M.; Hapke, M.; Harjes, J.; Hartz, P.; Haydar, R.; Haynes, W. J.; Heatherington, J.; Hedberg, V.; Hedgecock, R.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Herma, R.; Herynek, I.; Hildesheim, W.; Hill, P.; Hilton, C. D.; Hladký, J.; Hoeger, K. C.; Huet, Ph.; Hufnagel, H.; Huot, N.; Ibbotson, M.; Jabiol, M. A.; Jacholkowska, A.; Jacobsson, C.; Jaffre, M.; Jönsson, L.; Johannsen, K.; Johnson, D. P.; Johnson, L.; Jung, H.; Kalmus, P. I. P.; Kasarian, S.; Kaschowitz, R.; Kasselmann, P.; Kathage, U.; Kaufmann, H. H.; Kenyon, I. R.; Kermiche, S.; Kiesling, C.; Klein, M.; Kleinwort, C.; Knies, G.; Köhler, T.; Kolanoski, H.; Kole, F.; Kolya, S. D.; Korbel, V.; Korn, M.; Kostka, P.; Kotelnikov, S. K.; Krasny, M. W.; Krehbiel, H.; Krücker, D.; Krüger, U.; Kubenka, J. P.; Küster, H.; Kuhlen, M.; Kurça, T.; Kurzhöfer, J.; Kuznik, B.; Lander, R.; Landon, M. P. J.; Langkau, R.; Lanius, P.; Laporte, J. F.; Lebedev, A.; Leuschner, A.; Leverenz, C.; Levin, D.; Levonian, S.; Ley, Ch.; Lindner, A.; Lindström, G.; Loch, P.; Lohmander, H.; Lopez, G. C.; Lüers, D.; Magnussen, N.; Malinovski, E.; Mani, S.; Marage, P.; Marks, J.; Marshall, R.; Martens, J.; Martin, R.; Martyn, H.-U.; Martyniak, J.; Masson, S.; Mavroidis, A.; Maxfield, S. J.; McMahon, S. J.; Mehta, A.; Meier, K.; Merz, T.; Meyer, C. A.; Meyer, H.; Meyer, J.; Mikocki, S.; Milone, V.; Monnier, E.; Moreau, F.; Moreels, J.; Morris, J. V.; Morton, J. M.; Müller, K.; Murín, P.; Murray, S. A.; Nagovizin, V.; Naroska, B.; Naumann, Th.; Newton, D.; Nguyen, H. K.; Niebergall, F.; Nisius, R.; Nowak, G.; Noyes, G. W.; Nyberg, M.; Oberlack, H.; Obrock, H.; Olsson, J. E.; Orenstein, S.; Ould-Saada, F.; Pascaud, C.; Patel, G. D.; Peppel, E.; Peters, S.; Phillips, H. T.; Phillips, J. P.; Pichler, Ch.; Pilgram, W.; Pitzl, D.; Prosi, R.; Raupach, F.; Rauschnabel, K.; Reimer, P.; Ribarics, P.; Riech, V.; Riedlberger, J.; Rietz, M.; Robertson, S. M.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Royon, C.; Rudowicz, M.; Ruffer, M.; Rusakov, S.; Rybicki, K.; Ryseck, E.; Sacton, J.; Sahlmann, N.; Sanchez, E.; Sankey, D. P. C.; Savitsky, M.; Schacht, P.; Schleper, P.; von Schlippe, W.; Schmidt, C.; Schmidt, D.; Schmitz, W.; Schröder, V.; Schulz, M.; Schwind, A.; Scobel, W.; Seehausen, U.; Sell, R.; Seman, M.; Semenov, A.; Shekelyan, V.; Sheviakov, I.; Shooshtari, H.; Siegmon, G.; Siewert, U.; Sirois, Y.; Skillicorn, I. O.; Smirnov, P.; Smith, J. R.; Smolik, L.; Soloviev, Y.; Spitzer, H.; Staroba, P.; Steenbock, M.; Steffen, P.; Steinberg, R.; Steiner, H.; Stella, B.; Stephens, K.; Stier, J.; Strachota, J.; Straumann, U.; Struczinski, W.; Sutton, J. P.; Taylor, R. E.; Thompson, G.; Thompson, R. J.; Tichomirov, I.; Trenkel, C.; Truöl, P.; Tchernyshov, V.; Turnau, J.; Tutas, J.; Urban, L.; Usik, A.; Valkar, S.; Valkarova, A.; Vallee, C.; van Esch, P.; Vartapetian, A.; Vazdik, Y.; Vecko, M.; Verrecchia, P.; Vick, R.; Villet, G.; Vogel, E.; Wacker, K.; Walker, I. W.

    1993-01-01

    We present first results on the total photoproduction cross section measurement with the H1 detector at HERA. The data were extracted from low Q2 collisions of 26.7 GeV electrons with 820 GeV protons. The ?p total cross section has been measured by two independent methods in the ?p center of mass energy range from 90 to 290 GeV. For an average center of mass energy of 195 GeV a value of ?tot (?p) = 159 +/- 7 (stat.) +/- 20 (syst.) ?b was obtained. Supported by the Swedish Natural Science Research Council.

  4. Ultramicrotomy of diamond films for TEM cross-section analysis.

    PubMed

    Swab, P

    1995-07-01

    Ultramicrotomy has been used to prepare TEM cross-sections of typical hard dielectric, semiconductor, and metal coatings, providing a critical capability in the study of structure-property relationships of thin films. Ultramicrotomy of thin film coatings requires meticulous attention to technique and handling. The sample to be microtomed must be very small, well bonded to the epoxy embedding medium, and precisely oriented. In this article we report the ability to microtome TEM cross-sections of diamond and cubic boron-nitride (cBN) coatings. PMID:7549004

  5. Suppressed fusion cross section for neutron halo nuclei

    E-print Network

    Makoto Ito; Kazuhiro Yabana; Takashi Nakatsukasa; Manabu Ueda

    2006-01-20

    Fusion reactions of neutron-halo nuclei are investigated theoretically with a three-body model. The time-dependent wave-packet method is used to solve the three-body Schrodinger equation. The halo neutron behaves as a spectator during the Coulomb dissociation process of the projectile. The fusion cross sections of 11Be-209Bi and 6He-238U are calculated and are compared with measurements. Our calculation indicates that the fusion cross section is slightly hindered by the presence of weakly bound neutrons.

  6. Differential Cross Sections for Proton-Proton Elastic Scattering

    NASA Technical Reports Server (NTRS)

    Norman, Ryan B.; Dick, Frank; Norbury, John W.; Blattnig, Steve R.

    2009-01-01

    Proton-proton elastic scattering is investigated within the framework of the one pion exchange model in an attempt to model nucleon-nucleon interactions spanning the large range of energies important to cosmic ray shielding. A quantum field theoretic calculation is used to compute both differential and total cross sections. A scalar theory is then presented and compared to the one pion exchange model. The theoretical cross sections are compared to proton-proton scattering data to determine the validity of the models.

  7. Controlling inclusive cross sections in parton shower + matrix element merging

    E-print Network

    Simon Platzer

    2012-12-03

    We propose an extension of matrix element plus parton shower merging at tree level to preserve inclusive cross sections obtained from the merged and showered sample. Implementing this constraint generates approximate next-to-leading order (NLO) contributions similar to the LoopSim approach. We then show how full NLO, or in principle even higher order, corrections can be added consistently, including constraints on inclusive cross sections to account for yet missing parton shower accuracy at higher logarithmic order. We also show how NLO accuracy below the merging scale can be obtained.

  8. MINING INTEGRAL ACTINIDES CROSS SECTIONS FROM REACTOR DATA

    SciTech Connect

    PUIGH RJ

    2009-09-11

    The conclusions of this paper are: (1) mining of actinide cross-sections from reactor data is a viable and inexpensive approach to confirm burn-up codes; (2) extensive data for actinides in Hanford test data ({approx} 200 radiochemical analyses); (3) not only cross-section values and reaction rates can be established but also possible benchmark like data can be constructed to test and validate reactor and criticality safety codes such as SCALE/KENO or MCNPX; and (4) analysis along multiple transmutation paths can be evaluated to show consistency.

  9. A time projection chamber for high accuracy and precision fission cross-section measurements

    NASA Astrophysics Data System (ADS)

    Heffner, M.; Asner, D. M.; Baker, R. G.; Baker, J.; Barrett, S.; Brune, C.; Bundgaard, J.; Burgett, E.; Carter, D.; Cunningham, M.; Deaven, J.; Duke, D. L.; Greife, U.; Grimes, S.; Hager, U.; Hertel, N.; Hill, T.; Isenhower, D.; Jewell, K.; King, J.; Klay, J. L.; Kleinrath, V.; Kornilov, N.; Kudo, R.; Laptev, A. B.; Leonard, M.; Loveland, W.; Massey, T. N.; McGrath, C.; Meharchand, R.; Montoya, L.; Pickle, N.; Qu, H.; Riot, V.; Ruz, J.; Sangiorgio, S.; Seilhan, B.; Sharma, S.; Snyder, L.; Stave, S.; Tatishvili, G.; Thornton, R. T.; Tovesson, F.; Towell, D.; Towell, R. S.; Watson, S.; Wendt, B.; Wood, L.; Yao, L.

    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 4? 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.

  10. Reduced backscattering cross section (Sigma degree) data from the Skylab S-193 radar altimeter

    NASA Technical Reports Server (NTRS)

    Brown, G. S.

    1975-01-01

    Backscattering cross section per unit scattering area data, reduced from measurements made by the Skylab S-193 radar altimeter over the ocean surface are presented. Descriptions of the altimeter are given where applicable to the measurement process. Analytical solutions are obtained for the flat surface impulse response for the case of a nonsymmetrical antenna pattern. Formulations are developed for converting altimeter AGC outputs into values for the backscattering cross section. Reduced data are presented for Missions SL-2, 3 and 4 for all modes of the altimeter where sufficient calibration existed. The problem of interpreting land scatter data is also discussed. Finally, a comprehensive error analysis of the measurement is presented and worst case random and bias errors are estimated.

  11. A Time Projection Chamber for High Accuracy and Precision Fission Cross-Section Measurements

    SciTech Connect

    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.

  12. Effect of finite range of the NN force and NN cross section on reaction cross section for neutron rich nuclei

    SciTech Connect

    Ismail, M.; Ellithi, A.Y.; Abou-Shady, H.

    2005-02-01

    The reaction cross section ({sigma}{sub R}) is calculated using the optical limit of the Glauber theory. A density-dependent effective nucleon-nucleon (NN) cross section {sigma}{sub NN} is considered. Finite and zero range NN interactions are studied. The effect of finite range and an appropriate local density can increase {sigma}{sub R} up to 20% compared to the zero range at constant density (0.16 fm{sup -3}), while a zero range calculation with free NN cross section increases {sigma}{sub R} up to 13%. These factors affect the values of the rms radii for neutron rich nuclei extracted from {sigma}{sub R}.

  13. Adolescent Idiopathic Scoliosis and Eating Disorders: Is There a Relation? Results of a Cross-Sectional Study

    ERIC Educational Resources Information Center

    Zaina, Fabio; Donzelli, Sabrina; Lusini, Monia; Vismara, Luca; Capodaglio, Paolo; Neri, Laura; Negrini, Stefano

    2013-01-01

    A recent study suggests a correlation between idiopathic scoliosis in adolescence and eating disorders. However, this does not correspond with our clinical experience in the same population. The aim of this study was to verify the correlation between scoliosis and eating disorders in adolescence. A cross-sectional study was designed including 187…

  14. Pulmonary Rehabilitation in Ontario: A Cross-Sectional Survey

    PubMed Central

    Bowen, James M; Campbell, Kaitryn; Sutherland, Simone; Bartlett, Ann; Brooks, Dina; Qureshi, Riaz; Goldstein, Roger; Gershon, Andrea S; Prevost, Shelley; Samis, Lorelei; Kaplan, Alan G; Hopkins, Robert B; MacDougald, Craig; Nunes, Erica; O'Reilly, Daria J; Goeree, Ron

    2015-01-01

    Background Pulmonary rehabilitation (PR) is a comprehensive intervention of exercise training, education, and behaviour change to improve the physical and psychological condition of people with chronic respiratory disorders, such as chronic obstructive pulmonary disease (COPD) and to promote long-term adherence to health-enhancing behaviours. Although PR is considered the standard of care for patients with COPD who remain symptomatic despite bronchodilator therapies, current evidence suggests that only 1.15% of COPD patients across Canada have access to PR facilities for care. Objectives The objectives of this study were to identify the number of health care facilities across Ontario providing PR services for patients with COPD, describe the scope of those services, and determine the province's current capacity to provide PR services relative to need, for the province as a whole and by local health integration network (LHIN). Methods The Pulmonary Rehabilitation Programs in Ontario (PRO) Survey was a province-wide, descriptive, cross-sectional survey of health care facilities (hospitals, family health teams, and community health centres). It was distributed to 409 facilities to collect information on various aspects of PR services in the province. Results Between April 2013 and February 2014, 187 facilities responded to the survey (46% response rate). Most responding centres (144) did not offer PR services, and only 43 were full PR sites providing a comprehensive program. Hospital-based programs made up the majority of sites offering full PR services (67%), followed by programs based at family health teams (19%) and community health centres (14%). More than 90% of PR programs are outpatient-based. The average wait time for outpatient PR was 6.9 weeks, and 58% of programs provide services 5 days per week. More than 80% of patients attending PR complete the full program. Across all program types, the total estimated provincial capacity for PR outpatient care is 4,524 patients per year, or 0.66% to 1.78% of patients with COPD, depending on the estimated prevalence of disease. Limitations These results are representative of 12 of the 14 LHINs in Ontario due to low response rates in facilities in 2 LHINs. Conclusions Although some increase in capacity has occurred since a similar survey in 2005, PR resources in Ontario are insufficient to support the delivery of care to people with COPD in accordance with clinical practice guideline recommendations. PMID:26366242

  15. Measurements of differential scattering cross section using a ring transducer

    E-print Network

    Mast, T. Douglas

    Measurements of differential scattering cross section using a ring transducer Tomas T. Janssona using similar fixed transducer configurations. © 1998 Acoustical Society of America. S0001-4966 98 00306 to have different ultrasonic scattering properties under some circumstances.1­5 These differences arise

  16. 18. Cross section of Mormon Flat Dam completed. Structure on ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Cross section of Mormon Flat Dam completed. Structure on parapet contains the operating mechanisms for the penstock gates. Power house is not yet under construction. Photographer unknown, 1926. Source: Salt River Project. - Mormon Flat Dam, On Salt River, Eastern Maricopa County, east of Phoenix, Phoenix, Maricopa County, AZ

  17. Cross section measurements via residual nuclear decays: Analysis methods

    SciTech Connect

    Zhou Fengqun; Gao Lei; Li Kuohu; Song Yueli; Zhang Fang; Kong Xiangzhong; Luo Junhua

    2009-11-15

    We develop an approach to calculating the pure cross section of the ground state of artificial radioactive nuclides that subtracts the effect of an excited state on the ground state. We apply a formalism to obtaining pure cross sections by subtracting the effect of excited states in the reactions {sup 122}Te(n,2n){sup 121}Te{sup g} and {sup 128}Te(n,2n){sup 127}Te{sup g}, induced by neutrons of about 14 MeV. The cross sections are measured by an activation relative to the {sup 93}Nb(n,2n){sup 92}Nb{sup m} reaction and are compared with results that take into account the effect of the excited state. Measurements are carried out by {gamma} detection using a coaxial high-purity germanium (HPGe) detector. As samples, spectroscopically pure Te powder is used. The fast neutrons are produced by the {sup 3}H(d,n){sup 4}He reaction. The neutron energies in these measurements are determined using the method of cross-section ratios between the {sup 90}Zr(n,2n){sup 89}Zr{sup m+g} and {sup 93}Nb(n,2n){sup 92}Nb{sup m} reactions.

  18. Skin Diseases: Cross-section of human skin

    MedlinePLUS

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Cross-section of human skin Past Issues / Fall 2008 Table of Contents For ... Logical Images, Inc. I n the areas of skin health and skin diseases, the NIH's National Institute ...

  19. Relationship between cross-sectional and time series studies

    SciTech Connect

    Evans, J.S.; Kinney, P.L.; Koehler, J.L.; Cooper, D.W.

    1984-05-01

    Two classes of observational studies have provided quantitative estimates of the influence of air pollution on mortality. These are cross-sectional and time series studies. Cross-sectional studies examine geographical variations in community mortality rates and air pollution levels and typically involve fitting the parameters of proportional exposure-mortality functions by least squares regression analysis. Control for health-related covariates of pollution, such as socioeconomic status and smoking, is accomplished by inclusion of additional variables in the regression equation. Typically the averaging time for these analyses is one year; and therefore, many assume that these studies reflect chronic effects. Time series studies examine temporal variatons in death rates and air pollution levels in a single community. Using days as the unit of observation and averaging over the community, the parameters of the models are estimated by least squares techniques. Control for covariates is accomplished by reexpressing variables as deviations from trend lines and by including weather variables in the regression equation. Studies using these techniques reflect only the acute effects of air pollution. The similarity in the disease-specific findings of time series studies and cross-sectional studies which were analyzed is discussed. It is possible that the cross-sectional studies which have been conducted to date have reflected the impacts of acute rather than chronic effects of air pollution.

  20. Absolute cross sections for elastic electron scattering from 3-hydroxytetrahydrofuran

    NASA Astrophysics Data System (ADS)

    Milosavljevi?, A. R.; Blanco, F.; Maljkovi?, J. B.; Ševi?, D.; García, G.; Marinkovi?, B. P.

    2008-10-01

    The results of measurements and calculations of absolute cross sections for elastic electron scattering from the 3-hydroxytetrahydrofuran (3hTHF) (C4H8O2) molecule are reported. The measurements were performed using a crossed beam experimental setup, for an incident electron energy range of 40 300 eV and an overall scattering angle range of 10° 110°. Relative differential cross sections (DCSs) were measured both as a function of the angle and the incident energy and the absolute DCSs were determined using the relative flow technique. The calculations of molecular cross sections are based on a corrected form of the independent-atom method, known as the screen corrected additivity rule (SCAR) procedure and using an improved quasifree absorption model. Additional calculations are also done to investigate the influence of rotational excitations and low-angular behavior of SCAR DCSs. The calculated dataset includes differential, integral and total cross sections in the energy range from 5 eV to 10 000 eV. The present results are discussed regarding the most recent low-energy elastic DCSs for 3hTHF (Vizcaino et al 2008 New J. Phys. 10 053002), as well as the recent DCSs for molecules of similar structure (tetrahydrofuran and tetrahydrofurfuryl alcohol).

  1. RZ calculations for self shielded multigroup cross sections

    SciTech Connect

    Li, M.; Sanchez, R.; Zmijarevic, I.; Stankovski, Z.

    2006-07-01

    A collision probability method has been implemented for RZ geometries. The method accounts for white albedo, specular and translation boundary condition on the top and bottom surfaces of the geometry and for a white albedo condition on the outer radial surface. We have applied the RZ CP method to the calculation of multigroup self shielded cross sections for Gadolinia absorbers in BWRs. (authors)

  2. Cross Sections: No 6 Hold Section at Fr 178 Looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Cross Sections: No 6 Hold Section at Fr 178 Looking Fwd, No 7 Hold Section at No 154 Looking Fwd, No 7 Hold Section at Fr 195 Looking Fwd Showing Trans 194, No 7 Hold Section at Fr 198 Looking Fwd - General John Pope, Suisun Bay Reserve Fleet, Benicia, Solano County, CA

  3. Cross Sections: No. 1 Hold section at Fr 24 Looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Cross Sections: No. 1 Hold section at Fr 24 Looking Fwd, No 1 Hold Section at Fr 28 Looking Aft, No 2 Hold Section at Fr 48 Looking Aft, No 3 Hold Section at Fr 70 Looking Aft, No 4 Hold Section at Fr 90 Looking Aft - General John Pope, Suisun Bay Reserve Fleet, Benicia, Solano County, CA

  4. Note: Absolute photoionization cross-section of the vinyl radical

    NASA Astrophysics Data System (ADS)

    Savee, John D.; Lockyear, Jessica F.; Borkar, Sampada; Eskola, Arkke J.; Welz, Oliver; Taatjes, Craig A.; Osborn, David L.

    2013-08-01

    This work measures the absolute photoionization cross-section of the vinyl radical (?vinyl(E)) between 8.1 and 11.0 eV. Two different methods were used to obtain absolute cross-section measurements: 193 nm photodissociation of methyl vinyl ketone (MVK) and 248 nm photodissociation of vinyl iodide (VI). The values of the photoionization cross-section for the vinyl radical using MVK, ?vinyl(10.224 eV) = (6.1 ± 1.4) Mb and ?vinyl(10.424 eV) = (8.3 ± 1.9) Mb, and using VI, ?vinyl(10.013 eV) = (4.7 ± 1.1) Mb, ?vinyl(10.513 eV) = (9.0 ± 2.1) Mb, and ?vinyl(10.813 eV) = (12.1 ± 2.9) Mb, define a photoionization cross-section that is ˜1.7 times smaller than a previous determination of this value.

  5. Top quark cross-section measurements at the Tevatron

    SciTech Connect

    Wolfgang Wagner

    2003-12-11

    Run II of the Tevatron collider at Fermilab is well under way and data samples larger than those of Run I are at hand. In this contribution the author summarizes the current status of cross-section measurements for top-quark pair (t{bar t}) production at the CDF and D0 experiments.

  6. Accurate momentum transfer cross section for the attractive Yukawa potential

    SciTech Connect

    Khrapak, S. A.

    2014-04-15

    Accurate expression for the momentum transfer cross section for the attractive Yukawa potential is proposed. This simple analytic expression agrees with the numerical results better than to within ±2% in the regime relevant for ion-particle collisions in complex (dusty) plasmas.

  7. Cross-section of Calcite Crystal Covering in Jewel Cave

    USGS Multimedia Gallery

    Jewel Cave is currently the 3rd most extensive cave network in the world. It is believed to have formed completely underwater, thus leading to the extensive coating of calcite crystals. A cross-sectional view of the crystal coating can be seen in the center of the image, with the surface of the cal...

  8. Elastic photonuclear cross sections for bremsstrahlung from relativistic ions

    E-print Network

    R. E. Mikkelsen; A. H. Sørensen; U. I. Uggerhøj

    2015-10-09

    In this paper, we provide a procedure to calculate the bremsstrahlung spectrum for virtually any relativistic bare ion with charge 6$e$ or beyond, $Z\\ge 6$, in ultraperipheral collisions with target nuclei. We apply the Weizs\\"{a}cker-Williams method of virtual quanta to model the effect of the distribution of nuclear constituents on the interaction of the ion with the radiation target. This leads to a bremsstrahlung spectrum peaking at $2\\gamma$ times the energy of the giant dipole resonance ($\\gamma$ is the projectile energy in units of its rest energy). A central ingredient in the calculation is the cross section for elastic scattering of photons on the ion. This is only available in the literature for a few selected nuclei and, usually, only in a rather restricted parameter range. Hence we develop a procedure applicable for all $Z\\geq6$ to estimate the elastic scattering. The elastic cross section is obtained at low to moderate photon energies, somewhat beyond the giant dipole resonance, by means of the optical theorem, a dispersion relation, and data on the total absorption cross section. The cross section is continued at higher energies by invoking depletion due to loss of coherence in the scattering. Our procedure is intended for any ion where absorption data is available and for moderate to high energies, $\\gamma \\gtrsim 10$.

  9. EXPERIMENTAL PROTOCOL FOR DETERMINING ABSORPTION CROSS SECTIONS OF ORGANIC COMPOUNDS

    EPA Science Inventory

    An experimental protocol for the determination of gas phase absorption cross-sections, and calculation of maximum photolysis rates, has been developed and is described in detail. Utilization of this protocol will provide a basis for evaluating the possible relative importance of ...

  10. 11. Photograph of a line drawing. 'CROSS SECTION OF GAS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Photograph of a line drawing. 'CROSS SECTION OF GAS PRODUCER.' From George R. Cooper (Wilputte Corporation). 'Operating Overview of a Producer Gas Plant (12 Machines) at Kingsport, Tennessee.' Presented at the Fifth Annual International Conference on Coal Gasification, Liquefaction and Conversion to Electricity. University of Pittsburgh, August 2, 1978. - Holston Army Ammunition Plant, Producer Gas Plant, Kingsport, Sullivan County, TN

  11. LLNL-TR-446331 ENDF Cross Sections are not

    E-print Network

    Cullen, Red

    LLNL-TR-446331 ENDF Cross Sections are not Uniquely Defined by Dermott E. Cullen Lawrence Livermore National Laboratory Personal Contact Information 1466 Hudson Way Livermore, CA 94550 Tele: 925-443-19211 E by an agency of the United States government. Neither the United States government nor Lawrence Livermore

  12. Measurement of the Z??? cross section with the ATLAS detector

    E-print Network

    Taylor, Frank E.

    The Z??? cross section is measured with the ATLAS experiment at the LHC in four different final states determined by the decay modes of the ? leptons: muon-hadron, electron-hadron, electron-muon, and muon-muon. The analysis ...

  13. Radar cross sections of standard and complex shape targets

    NASA Technical Reports Server (NTRS)

    Sohel, M. S.

    1974-01-01

    The theoretical, analytical, and experimental results are described for radar cross sections (RCS) of different-shaped targets. Various techniques for predicting RCS are given, and RCS of finite standard targets are presented. Techniques used to predict the RCS of complex targets are made, and the RCS complex shapes are provided.

  14. 35. 'Firing Pier, Cross Sections, Looking South,' submitted 29 December ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. 'Firing Pier, Cross Sections, Looking South,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3874-46, Y&D Drawing 190848. Scale 1/8' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

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

    NASA Astrophysics Data System (ADS)

    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.; Henderson, D.; Jiang, C. L.; Lai, J.; Marley, S. T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R. C.; Paul, M.; Ugalde, C.

    2015-06-01

    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.

  16. Predictions for pp single diffractive cross section at LHC

    E-print Network

    Poghosyan, M G

    2012-01-01

    A model based on Gribov's Regge calculus was developed [1] and was proposed to describe diffractive processes. In this note we present numerical vales obtained from [1] for the dependence of single diffraction cross-section on diffractive mass at $\\sqrt{s}$ = 0.9, 2.76 and 7 TeV.

  17. NEODYMIUM NEUTRON CROSS SECTION MEASUREMENTS D. P. Barry1

    E-print Network

    Danon, Yaron

    NEODYMIUM NEUTRON CROSS SECTION MEASUREMENTS D. P. Barry1 , M. J. Trbovich1 , Y. Danon1 , R. C at the Rensselaer Polytechnic Institute LINAC using metallic neodymium samples. The capture measurements were made for all naturally occurring neodymium isotopes lie within the energy range of 1.0­ 500 eV. The resulting

  18. Displacement Kerma Cross Sections for Neutron Interactions in Molybdenum

    SciTech Connect

    A. M. Ougouag; C. A. Wemple; C. D. Van Siclen

    2004-04-01

    Modifications to the displacement kerma cross section methods employed in the NJOY99 nuclear data processing code are described. Calculations were performed with the modified code for molybdenum using ENDF-6 neutron interaction data. Results are presented for a range of plausible Ed values.

  19. Generation of cross section library for lattice physics code, AEGIS

    SciTech Connect

    Yamamoto, A.; Tada, K.; Sugimura, N.; Ushio, T.; Mori, M.

    2006-07-01

    This paper describes generation of cross section library (AELIB) for lattice physics code, AEGIS. Furthermore, an issue of the NJOY code that has considerable impact on multi-group scattering matrix in thermal energy range is pointed out and its solution is provided. (authors)

  20. Measurement of inclusive jet cross sections in photoproduction at HERA

    NASA Astrophysics Data System (ADS)

    H1 Collaboration; Abt, I.; Ahmed, T.; Andreev, V.; Andrieu, B.; Appuhn, R.-D.; Arpagaus, M.; Babaev, A.; Bärwolff, H.; Bán, J.; Baranov, P.; Barrelet, E.; Bartel, W.; Bassler, U.; Beck, H. P.; Behrend, H.-J.; Belousov, A.; Berger, Ch.; Bergstein, H.; Bernardi, G.; Bernet, R.; Bertrand-Coremans, G.; Besançon, M.; Biddulph, P.; Binder, E.; Bischoff, A.; Bizot, J. C.; Blobel, V.; Borras, K.; Bosetti, P. C.; Boudry, V.; Bourdarios, C.; Brasse, F.; Braun, U.; Braunschweig, W.; Brisson, V.; Bruncko, D.; Büngener, L.; Bürger, J.; Büsser, F. W.; Buniatian, A.; Burke, S.; Buschhorn, G.; Campbell, A. J.; Carli, T.; Charles, F.; Clarke, D.; Clegg, A. B.; Colombo, M.; Coughlan, J. A.; Courau, A.; Coutures, Ch.; Cozzika, G.; Criegee, L.; Cvach, J.; Dagoret, S.; Dainton, J. B.; Danilov, M.; Dann, A. W. E.; Dau, W. D.; David, M.; Deffur, E.; Delcourt, B.; del Buono, L.; Devel, M.; de Roeck, A.; Dingus, P.; Dollfus, C.; Dowell, J. D.; Dreis, H. B.; Drescher, A.; Duboc, J.; Düllmann, D.; Dünger, O.; Duhm, H.; Ebbinghaus, R.; Eberle, M.; Ebert, J.; Ebert, T. R.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eichenberger, S.; Eichler, R.; Eisele, F.; Eisenhandler, E.; Ellis, N. N.; Ellison, R. J.; Elsen, E.; Erdmann, M.; Evrard, E.; Favart, L.; Fedotov, A.; Feeken, D.; Felst, R.; Feltesse, J.; Fensome, I. F.; Ferencei, J.; Ferrarotto, F.; Flamm, K.; Flauger, W.; Fleischer, M.; Flügge, G.; Fomenko, A.; Fominykh, B.; Forbush, M.; Formánek, J.; Foster, J. M.; Franke, G.; Fretwurst, E.; Fuhrmann, P.; Gabathuler, E.; Gamerdinger, K.; Garvey, J.; Gayler, J.; Gellrich, A.; Gennis, M.; Genzel, H.; Gerhards, R.; Godfrey, L.; Goerlach, U.; Goerlich, L.; Goldberg, M.; Goodall, A. M.; Gorelov, I.; Goritchev, P.; Grab, C.; Grässler, H.; Grässler, R.; Greenshaw, T.; Greif, H.; Grindhammer, G.; Gruber, C.; Haack, J.; Haidt, D.; Hajduk, L.; Hamon, O.; Handschuh, D.; Hanlon, E. M.; Hapke, M.; Harjes, J.; Haydar, R.; Haynes, W. J.; Heatherington, J.; Hedberg, V.; Heinzelmann, G.; Henderson, R. C. W.; Henschel, H.; Herma, R.; Herynek, I.; Hildesheim, W.; Hill, P.; Hilton, C. D.; Hladký, J.; Hoeger, K. C.; Huet, Ph.; Hufnagel, H.; Huot, N.; Ibbotson, M.; Itterbeck, H.; Jabiol, M.-A.; Jacholkowska, A.; Jacobsson, C.; Jaffre, M.; Jansen, T.; Jönsson, L.; Johannsen, K.; Johnson, D. P.; Johnson, L.; Jung, H.; Kalmus, P. I. P.; Kasarian, S.; Kaschowitz, R.; Kasselmann, P.; Kathage, U.; Kaufmann, H. H.; Kenyon, I. R.; Kermiche, S.; Keuker, C.; Kiesling, C.; Klein, M.; Kleinwort, C.; Knies, G.; Ko, W.; Köhler, T.; Kolanoski, H.; Kole, F.; Kolya, S. D.; Korbel, V.; Korn, M.; Kostka, P.; Kotelnikov, S. K.; Krasny, M. W.; Krehbiel, H.; Krücker, D.; Krüger, U.; Kubenka, J. P.; Küster, H.; Kuhlen, M.; Kur?a, T.; Kurzhöfer, J.; Kuznik, B.; Lamarche, F.; Lander, R.; Landon, M. P. J.; Lange, W.; Langkau, R.; Lanius, P.; Laporte, J. F.; Lebedev, A.; Leuschner, A.; Leverenz, C.; Levonian, S.; Lewin, D.; Ley, Ch.; Lindner, A.; Lindström, G.; Linsel, F.; Lipinski, J.; Loch, P.; Lohmander, H.; Lopez, G. C.; Lüers, D.; Magnussen, N.; Malinovski, E.; Mani, S.; Marage, P.; Marks, J.; Marshall, R.; Martens, J.; Martin, R.; Martyn, H.-U.; Martyniak, J.; Masson, S.; Mavroidis, A.; Maxfield, S. J.; McMahon, S. J.; Mehta, A.; Meier, K.; Mercer, D.; Merz, T.; Meyer, C. A.; Meyer, H.; Meyer, J.; Mikocki, S.; Milone, V.; Monnier, E.; Moreau, F.; Moreels, J.; Morris, J. V.; Müller, K.; Murín, P.; Murray, S. A.; Nagovizin, V.; Naroska, B.; Naumann, Th.; Newton, D.; Neyret, D.; Nguyen, H. K.; Niebergall, F.; Nisius, R.; Nowak, G.; Noyes, G. W.; Nyberg, M.; Oberlack, H.; Obrock, U.; Olsson, J. E.; Orenstein, S.; Ould-Saada, F.; Pascaud, C.; Patel, G. D.; Peppel, E.; Peters, S.; Phillips, H. T.; Phillips, J. C.; Pichler, Ch.; Pilgram, W.; Pitzl, D.; Prell, S.; Prosi, R.; Rädel, G.; Raupach, F.; Rauschnabel, K.; Reimer, P.; Ribarics, P.; Riech, V.; Riedlberger, J.; Riess, S.; Rietz, M.; Robertson, S. M.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Royon, C.; Rudowicz, M.; Ruffer, M.; Rusakov, S.; Rybicki, K.; Sahlmann, N.; Sanchez, E.; Sankey, D. P. C.; Savitsky, M.; Schacht, P.; Schleper, P.; von Schlippe, W.; Schmidt, C.; Schmidt, D.; Schmitz, W.; Schröder, V.; Schulz, M.; Schwind, A.; Scobel, W.; Seehausen, U.; Sell, R.; Semenov, A.; Shekelyan, V.; Sheviakov, I.; Shooshtari, H.; Shtarkov, L. N.; Siegmon, G.; Siewert, U.; Sirois, Y.; Skillicorn, I. O.; Smirnov, P.; Smith, J. R.; Smolik, L.; Soloviev, Y.; Spitzer, H.; Staroba, P.; Steenbock, M.; Steffen, P.; Steinberg, R.; Stella, B.; Stephens, K.; Stier, J.; Stösslein, U.; Strachota, J.; Straumann, U.; Struczinski, W.; Sutton, J. P.; Taylor, R. E.; Tchernyshov, V.; Thiebaux, C.; Thompson, G.; Tichomirov, I.; Truöl, P.; Turnau, J.; Tutas, J.; Urban, L.; Usik, A.; Valkar, S.; Valkarova, A.; Vallée, C.; van Esch, P.

    1993-09-01

    The inclusive jet cross section in photoproduction has been measured as a function of transverse energy and pseudorapidity using the H 1 detector at the HERA electron-proton collider. The results are compared with leading order QCD calculations. Supported by the Swiss National Science Foundation.

  1. Soda Lake Well Lithology Data and Geologic Cross-Sections

    DOE Data Explorer

    Faulds, James E.

    2013-12-31

    Comprehensive catalogue of drill?hole data in spreadsheet, shapefile, and Geosoft database formats. Includes XYZ locations of well heads, year drilled, type of well, operator, total depths, well path data (deviations), lithology logs, and temperature data. Plus, 13 cross?sections in Adobe Illustrator format.

  2. Testing Weak Cross-Sectional Dependence in Large Panels

    E-print Network

    Pesaran, M. Hashem

    2012-02-28

    ), "General Diagnostic Tests for Cross Section Dependence in Panels", CESifo Working Paper Series No. 1229 ; IZA Discussion Paper No. 1240. Available at SSRN: http://ssrn.com/abstract=572504. 19 [18] Pesaran, M.H., Schuermann, T., and Weiner, S.M. (2004...

  3. 10. Historic American Buildings Survey CROSS SECTION ST. PATRICK'S ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Historic American Buildings Survey CROSS SECTION - ST. PATRICK'S R. C. CHURCH c. 1839 - JAMES GALLIER, ARCHITECT, IN COLLECTION OF THE LOUISIANA STATE MUSEUM, JACKSON SQUARE, NEW ORLEANS, LA. - St. Patrick's Roman Catholic Church, 724 Camp Street, New Orleans, Orleans Parish, LA

  4. Cross-sectional imaging of spin injection into a semiconductor

    E-print Network

    Loss, Daniel

    ARTICLES Cross-sectional imaging of spin injection into a semiconductor P. KOTISSEK1 , M. BAILLEUL1 successfully implemented--requires the creation and detection of spin-polarized currents in a semiconductor information about the spin polarization in the semiconductor. Here we introduce a method that, by observation

  5. 30 CFR 783.25 - Cross sections, maps, and plans.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... aquifers on cross-sections and contour maps; (7) Location of surface water bodies such as streams, lakes...) Elevations and locations of monitoring stations used to gather data on water quality and quantity, fish and... water, if encountered, within the proposed permit or adjacent areas, including, but not limited to...

  6. 30 CFR 783.25 - Cross sections, maps, and plans.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... aquifers on cross-sections and contour maps; (7) Location of surface water bodies such as streams, lakes...) Elevations and locations of monitoring stations used to gather data on water quality and quantity, fish and... water, if encountered, within the proposed permit or adjacent areas, including, but not limited to...

  7. 30 CFR 783.25 - Cross sections, maps, and plans.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... aquifers on cross-sections and contour maps; (7) Location of surface water bodies such as streams, lakes...) Elevations and locations of monitoring stations used to gather data on water quality and quantity, fish and... water, if encountered, within the proposed permit or adjacent areas, including, but not limited to...

  8. 30 CFR 783.25 - Cross sections, maps, and plans.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... aquifers on cross-sections and contour maps; (7) Location of surface water bodies such as streams, lakes...) Elevations and locations of monitoring stations used to gather data on water quality and quantity, fish and... water, if encountered, within the proposed permit or adjacent areas, including, but not limited to...

  9. 30 CFR 783.25 - Cross sections, maps, and plans.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... aquifers on cross-sections and contour maps; (7) Location of surface water bodies such as streams, lakes...) Elevations and locations of monitoring stations used to gather data on water quality and quantity, fish and... water, if encountered, within the proposed permit or adjacent areas, including, but not limited to...

  10. The radiation damage database: Section on helium cross section

    NASA Astrophysics Data System (ADS)

    Lu, W.; Wechsler, M. S.

    2007-04-01

    A radiation damage database with emphasis on spallation interactions is described. Currently, the database contains damage energy, displacement, helium, and hydrogen cross sections for 23 elemental targets irradiated by proton and neutron projectiles up to 3.2 GeV. In this paper, the focus is on proton-induced helium cross sections, but it is shown that for high energies (above about 500 MeV) proton- and neutron-induced helium cross sections are almost equal. The cross section calculations were run on the Cascade-Exciton Model code (no options) and also on the Bertini code with three nuclear level-density models and multistage pre-equilibrium model on and off. Calculation and experimental results are compared. For various targets, we tried to determine which code and options give best agreement with experiment. In some cases, such determinations are uncertain, partly because of limited and conflicting experimental information and partly perhaps because of the need for modifications in the codes.

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

    SciTech Connect

    Goulianos, Konstantin

    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.

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

    SciTech Connect

    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.; Henderson, D.; Jiang, C. L.; Lai, J.; Marley, S. T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R. C.; Paul, M.; Ugalde, C.; Giardina, G.; Eidelman, S.; Venanzoni, G.; Battaglieri, M.; Mandaglio, G.

    2015-06-02

    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.

  13. ORIGINAL ARTICLE A Cross-Sectional and Longitudinal Magnetic

    E-print Network

    Psychosis Min-Seong Koo, MD, PhD; James J. Levitt, MD; Dean F. Salisbury, PhD; Motoaki Nakamura, MD, Ph: A naturalistic cross-sectional study at first hos- pitalization for psychosis and a longitudinal follow. Thirty-nine patients with FESZ and 41 with FEAFF at first hospitalization for psychosis and 40 healthy

  14. Stellar neutron capture cross sections of the Lu isotopes

    SciTech Connect

    Wisshak, K.; Voss, F.; Kaeppeler, F.; Kazakov, L.

    2006-01-15

    The neutron capture cross sections of {sup 175}Lu and {sup 176}Lu have been measured in the energy range 3-225 keV at the Karlsruhe 3.7 MV Van de Graaff accelerator. Neutrons were produced via the {sup 7}Li(p,n){sup 7}Be reaction by bombarding metallic Li targets with a pulsed proton beam, and capture events were registered with the Karlsruhe 4{pi} barium fluoride detector. The cross sections were determined relative to the gold standard using isotopically enriched as well as natural lutetium oxide samples. Overall uncertainties of {approx}1% could be achieved in the final cross section ratios to the gold standard, about a factor of 5 smaller than in previous works. Maxwellian averaged neutron capture cross sections were calculated for thermal energies between kT = 8 and 100 keV. These values are systematically larger by {approx}7% than those reported in recent evaluations. These results are of crucial importance for the assessment of the s-process branchings at A 175/176.

  15. Inclusive Cross Sections in ME+PS Merging

    E-print Network

    Simon Plätzer

    2013-07-02

    We discuss an extension of matrix element plus parton shower merging at leading and next-to-leading order. The algorithm does preserve inclusive cross sections at the respective input order. This constraint avoids potentially large logarithmic contributions, which would require approximate (N)NLO contributions to cancel against.

  16. Electron scattering from hexafluoroacetone molecules: cross section measurements and calculations

    NASA Astrophysics Data System (ADS)

    Szmytkowski, Czes?aw; Mo?ejko, Pawe?; Ptasi?ska-Denga, El?bieta

    2011-10-01

    Absolute total cross section (TCS) for electron scattering from hexafluoroacetone (HFA: (CF3)2CO) molecules has been measured from 1 to 400 eV, employing a linear electron-transmission technique. The TCS energy function for the electron-HFA collision has two broad enhancements: the first, visible between 2 and 28 eV, can be partly attributed to resonant processes; the second is much broader, centred around 50 eV, and is characteristic of perfluorinated targets. The low-energy enhancement is superimposed with weak features perceptible near 3.6, 8.5 and 17 eV. Calculations were carried out for HFA and for acetone to obtain the integral elastic and ionization cross sections at intermediate and high incident energies, using the independent atom approximation and binary-encounter-Bethe approach, respectively. The computed total (elastic plus ionization) cross sections are above 70 eV in reasonable agreement with the experimental TCSs. A comparison is made between cross sections for HFA and its per-hydrogenated counterpart, acetone ((CH3)2CO); the effect of perfluorination is indicated.

  17. Neutron capture cross section of {sup 241}Am

    SciTech Connect

    Jandel, M.; Bredeweg, T. A.; Bond, E. M.; Chadwick, M. B.; Clement, R. R.; Couture, A.; O'Donnell, J. M.; Haight, R. C.; Kawano, T.; Reifarth, R.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Agvaanluvsan, U.; Parker, W. E.; Wu, C. Y.; Becker, J. A.

    2008-09-15

    The neutron capture cross section of {sup 241}Am for incident neutrons from 0.02 eV to 320 keV has been measured with the detector for advanced neutron capture experiments (DANCE) at the Los Alamos Neutron Science Center. The thermal neutron capture cross section was determined to be 665{+-}33 b. Our result is in good agreement with other recent measurements. Resonance parameters for E{sub n}<12 eV were obtained using an R-matrix fit to the measured cross section. The results are compared with values from the ENDF/B-VII.0, Mughabghab, JENDL-3.3, and JEFF-3.1 evaluations. {gamma}{sub n} neutron widths for the first three resonances are systematically larger by 5-15% than the ENDF/B-VII.0 values. The resonance integral above 0.5 eV was determined to be 1553{+-}7 b. Cross sections in the resolved and unresolved energy regions above 12 eV were calculated using the Hauser-Feshbach theory incorporating the width-fluctuation correction of Moldauer. The calculated results agree well with the measured data, and the extracted averaged resonance parameters in the unresolved resonance region are consistent with those for the resolved resonances.

  18. Flow structure caused by a local cross-sectional area increase and curvature in a sharp river bend

    NASA Astrophysics Data System (ADS)

    Vermeulen, B.; Hoitink, A. J. F.; Labeur, R. J.

    2015-09-01

    Horizontal flow recirculation is often observed in sharp river bends, causing a complex three-dimensional flow structure with large implications for the morphological and planimetric development of meanders. Several field observations in small-scale systems show that sharp bends are often found in association with a strong increase in cross-sectional area, the deposition of outer bank benches, and reattachment bars near the inner bank. Recent studies show that these bends can also occur in large-scale systems. In this study, we present field measurements of a sharp bend in the Mahakam River, East Kalimantan, Indonesia. The cross-sectional area increases by a factor of 3 compared with the reach-averaged cross-sectional area. Along a river reach of about 150 km, cross-sectional area correlates strongly with curvature. The field measurements are analyzed together with the results from numerical simulation with a three-dimensional finite element model, which yields a comprehensive view of the intricate flow structure. In turn, the model is used to validate a new equation that captures the water surface topography dependence on cross-sectional area variation and curvature. The results show the importance of the increase in cross-sectional area in the development of horizontal recirculation. Vertical acceleration of the flow into the scour causes the pressure to deviate from a hydrostatic pressure distribution. Strong downflow (up to 12 cm s-1) advects longitudinal momentum toward the bed, causing the flow to concentrate in the lower part of the cross section. This increases the velocity magnitude throughout the cross section, which is expected to maintain the large scour depth found in several bends along the Mahakam River.

  19. Froissart Bound on Inelastic Cross Section Without Unknown Constants

    E-print Network

    André Martin; S. M. Roy

    2015-03-31

    Assuming that axiomatic local field theory results hold for hadron scattering, Andr\\'e Martin and S. M. Roy recently obtained absolute bounds on the D-wave below threshold for pion-pion scattering and thereby determined the scale of the logarithm in the Froissart bound on total cross sections in terms of pion mass only. Previously, Martin proved a rigorous upper bound on the inelastic cross-section $\\sigma_{inel}$ which is one-fourth of the corresponding upper bound on $\\sigma_{tot}$, and Wu, Martin,Roy and Singh improved the bound by adding the constraint of a given $\\sigma_{tot}$. Here we use unitarity and analyticity to determine, without any high energy approximation, upper bounds on energy averaged inelastic cross sections in terms of low energy data in the crossed channel. These are Froissart-type bounds without any unknown coefficient or unknown scale factors and can be tested experimentally. Alternatively, their asymptotic forms,together with the Martin-Roy absolute bounds on pion-pion D-waves below threshold, yield absolute bounds on energy-averaged inelastic cross sections. E.g. for $\\pi^0 \\pi^0$ scattering, defining $\\sigma_{inel}=\\sigma_{tot} -\\big (\\sigma^{\\pi^0 \\pi^0 \\rightarrow \\pi^0 \\pi^0} + \\sigma^{\\pi^0 \\pi^0 \\rightarrow \\pi^+ \\pi^-} \\big )$,we show that for c.m. energy $\\sqrt{s}\\rightarrow \\infty $, $\\bar{\\sigma}_{inel }(s,\\infty)\\equiv s\\int_{s} ^{\\infty } ds'\\sigma_{inel }(s')/s'^2 \\leq (\\pi /4) (m_{\\pi })^{-2} [\\ln (s/s_1)+(1/2)\\ln \\ln (s/s_1) +1]^2$ where $1/s_1= 34\\pi \\sqrt{2\\pi }\\>m_{\\pi }^{-2} $ . This bound is asymptotically one-fourth of the corresponding Martin-Roy bound on the total cross section, and the scale factor $s_1$ is one-fourth of the scale factor in the total cross section bound. The average over the interval (s,2s) of the inelastic $\\pi^0 \\pi^0 $cross section has a bound of the same form with $1/s_1$ replaced by $1/s_2=2/s_1 $.

  20. Thermal neutron capture cross sections of the potassium isotopes

    NASA Astrophysics Data System (ADS)

    Firestone, R. B.; Krti?ka, M.; Révay, Zs.; Szentmiklosi, L.; Belgya, T.

    2013-02-01

    Precise thermal neutron capture ?-ray cross sections ?? for 39,40,41K were measured on a natural potassium target with the guided neutron beam at the Budapest Reactor. The cross sections were internally standardized using a stoichiometric KCl target with well-known 35Cl(n,?) ?-ray cross sections [Révay and Molnár, Radiochimica ActaRAACAP0033-823010.1524/ract.91.6.361.20027 91, 361 (2003); Molnár, Révay, and Belgya, Nucl. Instrum. Meth. Phys. Res. BNIMBEU0168-583X10.1016/S0168-583X(03)01529-5 213, 32 (2004)]. These data were combined with ?-ray intensities from von Egidy [von Egidy, Daniel, Hungerford, Schmidt, Lieb, Krusche, Kerr, Barreau, Borner, Brissot , J. Phys. G. Nucl. Phys.JPHGBM0305-461610.1088/0305-4616/10/2/013 10, 221 (1984)] and Krusche [Krusche, Lieb, Ziegler, Daniel, von Egidy, Rascher, Barreau, Borner, and Warner, Nucl. Phys. ANUPABL0375-947410.1016/0375-9474(84)90506-2 417, 231 (1984); Krusche, Winter, Lieb, Hungerford, Schmidt, von Egidy, Scheerer, Kerr, and Borner, Nucl. Phys. ANUPABL0375-947410.1016/0375-9474(85)90429-4 439, 219 (1985)] to generate nearly complete capture ?-ray level schemes. Total radiative neutron cross sections were deduced from the total ?-ray cross section feeding the ground state, ?0=???(GS) after correction for unobserved statistical ?-ray feeding from levels near the neutron capture energy. The corrections were performed with Monte Carlo simulations of the potassium thermal neutron capture decay schemes using the computer code dicebox where the simulated populations of low-lying levels are normalized to the measured cross section depopulating those levels. Comparisons of the simulated and experimental level feeding intensities have led to proposed new spins and parities for selected levels in the potassium isotopes where direct reactions are not a significant contribution. We determined the total radiative neutron cross sections ?0(39K)=2.28±0.04 b, ?0(40K)=90±7 b, and ?0(41K)=1.62±0.03 b from the prompt ?-ray data and the ?-ray transition probability P?(1524.66)=0.164(4) in the ?- decay of 42K in a low-background counting experiment.

  1. On the ratio of and cross sections at the CERN Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Bevilacqua, G.; Worek, M.

    2014-07-01

    Triggered by ongoing experimental analyses, we report on a study of the cross section ratio at the next-to-leading order in QCD, focusing on both present and future collider energies: = 7, 8, 13 TeV. In particular, we provide a comparison between our predictions and the currently available CMS data for the 8 TeV run. We further analyse the kinematics and scale uncertainties of the two processes for a single set of parton distribution functions, with the goal of assessing possible correlations that might help to reduce the theoretical error of the ratio and thus enhance the predictive power of this observable. We argue that the different jet kinematics makes the and processes uncorrelated in several observables, and show that the scale uncertainty is not significantly reduced when taking the ratio of the cross sections.

  2. Unified nonlinear analysis for nonhomogeneous anisotropic beams with closed cross sections

    NASA Technical Reports Server (NTRS)

    Atilgan, Ali R.; Hodges, Dewey H.

    1991-01-01

    A unified methodology for geometrically nonlinear analysis of nonhomogeneous, anisotropic beams is presented. A 2D cross-sectional analysis and a nonlinear 1D global deformation analysis are derived from the common framework of a 3D, geometrically nonlinear theory of elasticity. The only restrictions are that the strain and local rotation are small compared to unity and that warping displacements are small relative to the cross-sectional dimensions. It is concluded that the warping solutions can be affected by large deformation and that this could alter the incremental stiffnes of the section. It is shown that sectional constants derived from the published, linear analysis can be used in the present nonlinear, 1D analysis governing the global deformation of the beam, which is based on intrinsic equations for nonlinear beam behavior. Excellent correlation is obtained with published experimental results for both isotropic and anisotropic beams undergoing large deflections.

  3. On the cross-section of dark matter using substructure infall into galaxy clusters

    NASA Astrophysics Data System (ADS)

    Harvey, David; Tittley, Eric; Massey, Richard; Kitching, Thomas D.; Taylor, Andy; Pike, Simon R.; Kay, Scott T.; Lau, Erwin T.; Nagai, Daisuke

    2014-06-01

    We develop a statistical method to measure the interaction cross-section of dark matter, exploiting the continuous minor merger events in which small substructures fall into galaxy clusters. We find that by taking the ratio of the distances between the galaxies and dark matter, and galaxies and gas in accreting subhaloes, we form a quantity that can be statistically averaged over a large sample of systems whilst removing any inherent line-of-sight projections. To interpret this ratio as a cross-section of dark matter, we derive an analytical description of subhalo infall allowing us to constrain self-interaction models in which drag is an appropriate macroscopic treatment. We create mock observations from cosmological simulations of structure formation and find that collisionless dark matter becomes physically separated from X-ray gas by up to ˜20 h-1 kpc. Adding realistic levels of noise, we are able to predict achievable constraints from observational data. Current archival data should be able to detect a difference in the dynamical behaviour of dark matter and standard model particles at 6?, and measure the total interaction cross-section ?/m with 68 per cent confidence limits of ±1 cm2 g-1. We note that this method is not restricted by the limited number of major merging events and is easily extended to large samples of clusters from future surveys which could potentially push statistical errors to <0.1 cm2 g-1.

  4. Progress and open questions in the physics of neutrino cross sections at intermediate energies

    NASA Astrophysics Data System (ADS)

    Alvarez-Ruso, L.; Hayato, Y.; Nieves, J.

    2014-07-01

    New and more precise measurements of neutrino cross sections have renewed interest in a better understanding of electroweak interactions on nucleons and nuclei. This effort is crucial to achieving the precision goals of the neutrino oscillation program, making new discoveries, like the CP violation in the leptonic sector, possible. We review the recent progress in the physics of neutrino cross sections, putting emphasis on the open questions that arise in the comparison with new experimental data. Following an overview of recent neutrino experiments and future plans, we present some details about the theoretical development in the description of (anti)neutrino-induced quasielastic (QE) scattering and the role of multi-nucleon QE-like mechanisms. We cover not only pion production in nucleons and nuclei but also other inelastic channels including strangeness production and photon emission. Coherent reaction channels on nuclear targets are also discussed. Finally, we briefly describe some of the Monte Carlo event generators, which are at the core of all neutrino oscillation and cross-section measurements.

  5. Magnetostatic modes in ferromagnetic nanowires. II. A method for cross sections with very large aspect ratio

    NASA Astrophysics Data System (ADS)

    Arias, Rodrigo; Mills, D. L.

    2005-09-01

    We present a method which allows one to calculate the frequencies of the magnetostatic spin waves and their eigenvectors, for ferromagnetic nanowires of arbitrary cross section. The approach is based on application of the extinction theorem, and has the virtue that one need not resort to expansions in special basis sets built around a specific geometry of interest. Instead we develop integral equations in the form of contour integrals around the periphery of the wire which allows us to obtain both eigenfrequencies and eigenvectors. Our earlier formulation of the problem allowed computation of the dispersion relation of each magnetostatic mode, i.e., their frequency as a function of the wave vector parallel to the wire. It is a numerical challenge to apply this method to rectangular wires whose cross section has a very large aspect ratio, though it works splendidly when the aspect ratio is modest. In the present paper, we focus our attention on modes of zero wave vector, and through use of conformal mapping cast the extinction theorem description of the spin wave modes into a form that allows exact calculations for rectangular wires whose cross sections have extremely large aspect ratios. Comparison of our exact calculations with approximation schemes found in the literature allow us to assess the accuracy of such schemes. We also compare our calculated frequencies to Brillouin light scattering data on ferromagnetic ribbons of very high aspect ratio.

  6. Thermal Neutron Capture Cross Sections Of The Palladium Isotopes

    NASA Astrophysics Data System (ADS)

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

    2006-03-01

    We have measured precise thermal neutron capture ?-ray cross sections cry for all stable Palladium isotopes with the guided thermal neutron beam from the Budapest Reactor. The data were compared with other data from the literature and have been evaluated into the Evaluated Gamma-ray Activation File (EGAF). Total radiative neutron capture cross-sections ?? can be deduced from the sum of transition cross sections feeding the ground state of each isotope if the decay scheme is complete. The Palladium isotope decay schemes are incomplete, although transitions deexciting low-lying levels are known for each isotope. We have performed Monte Carlo simulations of the Palladium thermal neutron capture deexcitation schemes using the computer code DICEBOX. This program generates level schemes where levels below a critical energy Ecrit are taken from experiment, and those above Ecrit are calculated by a random discretization of an a priori known level density formula ?(E,J?). Level de-excitation branching intensities are taken from experiment for levels below Ecrit the capture state, or calculated for levels above Ecrit assuming an a priori photon strength function and applying allowed selection rules and a Porter-Thomas distribution of widths. The advantage of this method is that calculational uncertainties can be investigated systematically. Calculated feeding to levels below Ecrit can be normalized to the measured cross section deexciting those levels to determine the total radiative neutron cross-section ??. In this paper we report the cross section measurements ??[102Pd(n,?)]=0.9±0.3 b, ??[104Pd(n,?)=0.61±0.11 b, ??[105Pd(n,?)]=2.1.1±1.5 b, ??[106Pd(n,?)]=0.36±0.05 b, ??[108Pd(n,?)(0)]=7.6±0.6 b, ??[108Pd(n,?)(189)]=0.185±0.011 b, and ??[110Pd(n,?)]=0.10±0.03 b. We have also determined from our statistical calculations that the neutron capture states in 107Pd are best described as 2+[59(4)%]+3+[41(4)%]. Agreement with literature values was excellent in most cases. We found significant discrepancies between our results for 102Pd and 110Pd and earlier values that could be resolved by re-evaluation of the earlier results.

  7. NEUTRON CROSS SECTION COVARIANCES FROM THERMAL ENERGY TO 20 MeV.

    SciTech Connect

    ROCHMAN,D.; HERMAN, M.; OBLOZINSKY, P.; MUGHABGHAB, S.F.; PIGNI, M.; KAWANO, T.

    2007-04-27

    We describe new method for energy-energy covariance calculation from the thermal energy up to 20 MeV. It is based on three powerful basic components: (i) Atlas of Neutron Resonances in the resonance region; (ii) the nuclear reaction model code EMPIRE in the unresolved resonance and fast neutron regions, and (iii) the Bayesian code KALMAN for correlations and error propagation. Examples for cross section uncertainties and correlations on {sup 90}Zr and {sup 193}Ir illustrate this approach in the resonance and fast neutron regions.

  8. Unfolding the Boosted Top Quark Differential Cross Section

    NASA Astrophysics Data System (ADS)

    Berish, Danielle; Bellis, Matthew

    2014-03-01

    The high energy of the Large Hadron Collider at CERN makes possible the measurement of differential cross sections of the production of the top quark at higher momentum than previous studies. This provides a probe for tests of new physics. We used data from the CMS detector from the 2012, 8 TeV run. In these studies it is important to properly correct for efficiency and bias by using an unfolding process. We present a test of the robustness of the RooUnfold package, both the procedure in general and more specifically as it applies to the top quark measurement. The current status of the differential cross section measurement will be presented. This work was supported in part by NSF grant PHY-1307562.

  9. Impact dynamics of granular jets with noncircular cross sections.

    PubMed

    Cheng, Xiang; Gordillo, Leonardo; Zhang, Wendy W; Jaeger, Heinrich M; Nagel, Sidney R

    2014-04-01

    Using high-speed photography, we investigate two distinct regimes of the impact dynamics of granular jets with noncircular cross sections. In the steady-state regime, we observe the formation of thin granular sheets with anisotropic shapes and show that the degree of anisotropy increases with the aspect ratio of the jet's cross section. Our results illustrate the liquidlike behavior of granular materials during impact and demonstrate that a collective hydrodynamic flow emerges from strongly interacting discrete particles. We discuss the analogy between our experiments and those from the Relativistic Heavy Ion Collider, where similar anisotropic ejecta from a quark-gluon plasma have been observed in heavy-ion impact. PMID:24827235

  10. Improved activation cross sections for vanadium and titanium

    SciTech Connect

    Muir, D.W.; Arthur, E.D.

    1983-01-01

    Vanadium alloys such as V-20Ti and V-Cr-Ti are attractive candidates for use as structural materials in fusion-reactor blankets. The virtual absence of long-lived activation products in these alloys suggest the possibility of reprocessing on an intermediate time scale. We have employed the modern Hauser-Feshbach nuclear-model code GNASH to calculate cross sections for neutron-activation reactions in /sup 50/V and /sup 51/V, to allow a more accurate assessment of induced radioactivity in vanadium alloys. In addition, cross sections are calculated for the reactions /sup 46/Ti(n,2n) and /sup 45/Ti(n,2n) in order to estimate the production of /sup 44/Ti, a 1.2-MeV gamma-ray source with a half-life of 47 years.

  11. Systematic Measurement of pd Breakup Cross Section Around Space Star

    NASA Astrophysics Data System (ADS)

    Ohnaka, K.; Sagara, K.; Maeda, Y.; Ishibashi, K.; Kimura, S.; Tanaka, S.; Fukunaga, T.; Yasuda, J.; Yabe, T.; Yashima, K.; Eguchi, Y.; Shimoda, H.; Sueta, T.; Kuroita, S.

    2014-08-01

    Space Star (SS) anomaly in nd breakup cross section was first reported in 1989 at E n = 13 MeV (Strate et al. in Nucl Phys A 501:51, 1989), but its origin has not been found yet. In order to obtain suggestions for its origin, we made systematic measurements of pd breakup cross section around SS. In SS configuration, three outgoing nucleons form an equilateral triangle and the triangle is perpendicular to the beam axis. Necessity of the equilateral and perpendicular conditions of SS anomaly was investigated by systematic experiments. Also energy dependence of SS anomaly is being studied at energies from E p = 7.5 to 13 MeV.

  12. Software for Bayesian cross section and panel spatial model comparison

    NASA Astrophysics Data System (ADS)

    LeSage, James P.

    2015-10-01

    A wide variety of spatial regression specifications that include alternative types of spatial dependence (e.g., lagged values of the dependent variable, spatial lags of explanatory variables, dependence in the model disturbances) have been the focus of a literature on statistical tests for distinguishing between alternative specifications. LeSage (Spat Stat 9:122-145, 2014) argues that a Bayesian approach to model comparison for cross-sectional and static panel models considerably simplifies the task of selecting an appropriate model. MATLAB software functions for carrying out Bayesian cross-sectional and static spatial panel model comparisons described in LeSage (2014) are described here along with a number of illustrative applications.

  13. Turbulent combustion flow through variable cross section channel

    SciTech Connect

    Rogov, B.V.; Sokolova, I.A.

    1999-07-01

    The object of this study is to develop a new evolutionary numerical method for solving direct task of Laval nozzle, which provides non-iterative calculations of chemical reacting turbulent flows with detailed kinetic chemistry. The numerical scheme of fourth order along the normal coordinate and second order along the streamwise one is derived for calculation of difference-differential equations of the second order and the first order. Marching method provides the possibility of computing field flow in subsonic section of nozzle and near an expansion. Critical mass consumption is calculated with controlled accuracy. After critical cross section of nozzle a combined marching method with global iterations over axial pressure (only) makes it possible to overcome ill posedness of mixed supersonic flow and calculate the whole flow field near and after critical cross section. Numerical results are demonstrated on turbulent burning hydrogen-oxygen flow through Laval nozzle with curvature of wall K{sub w} = 0.5.

  14. Differential cross sections for e-LiF scattering

    SciTech Connect

    Siegel, Jon; Dehmer, Joseph L.; Dill, Dan

    1980-03-28

    Differential cross sections are calculated for e-LiF scattering from 1 to 20 eV using a three-part hybrid method in which low-l partial waves are calculated using the multiple-scattering method, intermediate-l partial waves are calculated using the closed-form point dipole method and high-l waves are obtained using the first Born approximation. Good agreement between theory and experiment at 5.44 and 20 eV confirms the suitability of both the three-part hybrid approach and of the three separate approximations used therein. The differential cross section spectrum is dominated by dipole scattering at small angles, but clearly shows the influence of the molecular core at intermediate and large angles. No evidence of resonant activity is seen in this energy range.

  15. Cross-Section Measurements with the Radioactive Isotope Accelerator (ria)

    NASA Astrophysics Data System (ADS)

    Stoyer, M. A.; Moody, K. J.; Wild, J. F.; Patin, J. B.; Shaughnessy, D. A.; Stoyer, N. J.; Harris, L. J.

    2003-10-01

    RIA will produce beams of exotic nuclei of unprecedented luminosity. Preliminary studies of the feasibility of measuring cross-sections of interest to the science based stockpile stewardship (SBSS) program will be presented, and several experimental techniques will be discussed. Cross-section modeling attempts for the A = 95 mass region will be shown. In addition, several radioactive isotopes could be collected for target production or medical isotope purposes while the main in-beam experiments are running. The inclusion of a broad range mass analyzer (BRAMA) capability at RIA will enable more effective utilization of the facility, enabling the performance of multiple experiments at the same time. This option will be briefly discussed.

  16. Elastic breakup cross sections of well-bound nucleons

    E-print Network

    K. Wimmer; D. Bazin; A. Gade; J. A. Tostevin; T. Baugher; Z. Chajecki; D. Coupland; M. A. Famiano; T. K. Ghosh; G. F. Grinyer M. E. Howard; M. Kilburn; W. G. Lynch; B. Manning; K. Meierbachtol; P. Quarterman; A. Ratkiewicz; A. Sanetullaev; R. H. Showalter; S. R. Stroberg; M. B. Tsang; D. Weisshaar; J. Winkelbauer; R. Winkler; M. Youngs

    2014-12-07

    The 9Be(28Mg,27Na) one-proton removal reaction with a large proton separation energy of Sp(28Mg)=16.79 MeV is studied at intermediate beam energy. Coincidences of the bound 27Na residues with protons and other light charged particles are measured. These data are analyzed to determine the percentage contributions to the proton removal cross section from the elastic and inelastic nucleon removal mechanisms. These deduced contributions are compared with the eikonal reaction model predictions and with the previously measured data for reactions involving the re- moval of more weakly-bound protons from lighter nuclei. The role of transitions of the proton between different bound single-particle configurations upon the elastic breakup cross section is also quantified in this well-bound case. The measured and calculated elastic breakup fractions are found to be in good agreement.

  17. Accurate Development of Thermal Neutron Scattering Cross Section Libraries

    SciTech Connect

    Hawari, Ayman; Dunn, Michael

    2014-06-10

    The objective of this project is to develop a holistic (fundamental and accurate) approach for generating thermal neutron scattering cross section libraries for a collection of important enutron moderators and reflectors. The primary components of this approach are the physcial accuracy and completeness of the generated data libraries. Consequently, for the first time, thermal neutron scattering cross section data libraries will be generated that are based on accurate theoretical models, that are carefully benchmarked against experimental and computational data, and that contain complete covariance information that can be used in propagating the data uncertainties through the various components of the nuclear design and execution process. To achieve this objective, computational and experimental investigations will be performed on a carefully selected subset of materials that play a key role in all stages of the nuclear fuel cycle.

  18. NIFFTE Time Projection Chamber for Fission Cross Section Measurements

    NASA Astrophysics Data System (ADS)

    Castillo, Ryan; Neutron Induced Fission Fragment Tracking Experiment Collaboration

    2011-10-01

    In order to design safer and more efficient Generation IV nuclear reactors, more accurate knowledge of fission cross sections is needed. The goal of the Time Projection Chamber (TPC) used by the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration is to measure the cross sections of several fissile materials to within 1% uncertainty. The ability of the TPC to produce 3D ``pictures'' of charged particle trajectories will eliminate unwanted alpha particles in the data. Another important source of error is the normalization of data the U-235 standard. NIFFTE will use the H(n,n)H reaction instead, which is known to better than 0.2%. The run control and monitoring system will eventually allow for nearly complete automation and off-site monitoring of the experiment. This presentation will cover the need for precision measurements and an overview of the experiment. This work was supported by the U.S. Department of Energy Division of Energy Research.

  19. Developing Scientific Reasoning Through Drawing Cross-Sections

    NASA Astrophysics Data System (ADS)

    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 sections were easy to visualize. Students in Structural Geology are proud of their cross-sections once they were inked and colored. Students in Advanced Structural Geology were confident in their digitized cross-sections, even before they had tried to balance them or had tested whether they were kinematically plausible. In both cases, visually attractive models seemed easier to believe. Three-dimensional models seemed even more convincing: if students could visualize the model, they also thought it should work geometrically and kinematically, whether they had tested it or not. Students were more inclined to test their models when they had a clear set of criteria that would indicate success or failure. However, future development of new ideas about the kinematic and/or mechanical development of structures may force the students to also decide which criteria fit their problem the best. Combining both kinds of critical thinking (evaluating techniques and evaluating their results) in the same assignment may be challenging.

  20. Ion induced fragmentation cross-sections of DNA constituents

    NASA Astrophysics Data System (ADS)

    Rudek, Benedikt; Arndt, Alexander; Bennett, Daniel; Wang, Mingjie; Rabus, Hans

    2015-10-01

    Proton collision with chemical analogs for the base, the sugar and the phosphor residue of the DNA, namely pyrimidine, tetrahydrofuran and trimethyl phosphate, respectively, has been investigated. The impact energies ranged from 300 keV up to 16 MeV. For the first time, relative fragmentation cross-sections for proton impact are reported for tetrahydrofuran and trimethyl phosphate; previously reported cross sections for pyrimidine are extended for energies beyond 2500 keV. Ionization of tetrahydrofuran leads to a ring break in about 80% of all events, trimethyl phosphate predominantly fragments by bond cleavage to one of the three methyl-groups and for pyrimidine the parent ion has the highest abundance. Such comparison supports earlier findings that the sugar is the weak spot for strand breaks.

  1. Electron scattering from pyrazine: elastic differential and integral cross sections.

    PubMed

    Palihawadana, P; Sullivan, J P; Buckman, S J; Brunger, M J

    2012-11-28

    We report on new measurements for elastic electron scattering from pyrazine. Absolute differential cross sections (DCSs) at seven discrete energies in the range 3-50 eV, and over the scattered electron angular range 10°-129°, were determined using a crossed electron-molecular beam spectrometer in conjunction with the well-established relative flow technique. Integral elastic cross sections were subsequently derived from those DCS data at each energy. Where possible comparison between the present results and those from sophisticated Schwinger multichannel and R-matrix computations is made, with generally quite good quantitative accord being found. Finally, in order to better study some of the rich resonance structure predicted by theory, results from elastic electron excitation functions are presented. PMID:23206003

  2. Higgs Boson Cross Section from CTEQ-TEA Global Analysis

    E-print Network

    Dulat, Sayipjamal; Gao, Jun; Huston, Joey; Nadolsky, Pavel; Pumplin, Jon; Schmidt, Carl; Stump, Daniel; Yuan, C -P

    2013-01-01

    We study the uncertainties of the Higgs boson production cross section through the gluon fusion subprocess at the LHC (with $\\sqrt s=7, 8$ and $14$ TeV) arising from the uncertainties of the parton distribution functions (PDFs) and of the value of the strong coupling constant $\\alpha_s(M_Z)$. These uncertainties are computed by two complementary approaches, based on the Hessian and the Lagrange Multiplier methods within the CTEQ-TEA global analysis framework. We find that their predictions for the Higgs boson cross section are in good agreement. Furthermore, the result of the Lagrange Multiplier method supports the prescriptions we have previously provided for using the Hessian method to calculate the combined PDF and $\\alpha_s$ uncertainties, and to estimate the uncertainties at the $68%$ confidence level by scaling them from the 90% confidence level.

  3. Higgs Boson Cross Section from CTEQ-TEA Global Analysis

    E-print Network

    Sayipjamal Dulat; Tie-Jiun Hou; Jun Gao; Joey Huston; Pavel Nadolsky; Jon Pumplin; Carl Schmidt; Daniel Stump; C. -P. Yuan

    2014-08-19

    We study the uncertainties of the Higgs boson production cross section through the gluon fusion subprocess at the LHC (with $\\sqrt s=7, 8$ and $14$ TeV) arising from the uncertainties of the parton distribution functions (PDFs) and of the value of the strong coupling constant $\\alpha_s(M_Z)$. These uncertainties are computed by two complementary approaches, based on the Hessian and the Lagrange Multiplier methods within the CTEQ-TEA global analysis framework. We find that their predictions for the Higgs boson cross section are in good agreement. Furthermore, the result of the Lagrange Multiplier method supports the prescriptions we have previously provided for using the Hessian method to calculate the combined PDF and $\\alpha_s$ uncertainties, and to estimate the uncertainties at the $68\\%$ confidence level by scaling them from the $90\\%$ confidence level.

  4. Calculation of the cross section for top quark production

    SciTech Connect

    Berger, E.L.; Contopanagos, H.

    1996-06-21

    The authors summarize calculations of the cross section for top quark production at hadron colliders within the context of perturbative quantum chromodynamics, including resummation of the effects of initial-state soft gluon radiation to all orders in the strong coupling strength. In their approach they resume the universal leading-logarithm contributions, and they restrict the calculation to the region of phase space that is demonstrably perturbative. They compare the approach with other methods. They present predictions of the physical cross section as a function of the top quark mass in proton-antiproton reactions at center-of-mass energies of 1.8 and 2.0 TeV, and they discuss estimated uncertainties.

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

    NASA Astrophysics Data System (ADS)

    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 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 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.

  6. A Study on 19F( n,?) Reaction Cross Section

    NASA Astrophysics Data System (ADS)

    U?ur, F. A.; Tel, E.; Gökçe, A. A.

    2013-06-01

    In this study, cross sections of neutron induced reactions have been investigated for fluorine target nucleus. The calculations have been made on the excitation functions of 19F ( n,?), 19F( n,x?) reactions. Fluorine (F) and its molten salt compounds (LiF) can serve as a coolant which can be used at high temperatures without reaching a high vapor pressure and also the molten salt compounds are also a good neutron moderator. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the full exciton model and the cascade exciton model. The equilibrium effects are calculated according to the Weisskopf-Ewing model. Also in the present work, reaction cross sections have calculated by using evaluated empirical formulas developed by Tel et al. at 14-15 MeV energy. The obtained results have been discussed and compared with the available experimental data.

  7. Neutron Capture Cross Sections of 236U and 234U

    SciTech Connect

    Rundberg, R. S.; Bredeweg, T. A.; Bond, E. M.; Haight, R. C.; Hunt, L. F.; O'Donnell, J. M.; Schwantes, J. M.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Kronenberg, A.

    2006-03-13

    Accurate neutron capture cross sections of the actinide elements at neutron energies up to 1 MeV are needed to better interpret archived nuclear test data, for post-detonation nuclear attribution, and the Advanced Fuel Cycle Initiative. The Detector for Advance Neutron Capture Experiments, DANCE, has unique capabilities that allow the differentiation of capture gamma rays from fission gamma rays and background gamma rays from scattered neutrons captured by barium isotopes in the barium fluoride scintillators. The DANCE array has a high granularity, 160 scintillators, high efficiency, and nearly 4-{pi} solid angle. Through the use of cuts in cluster multiplicity and calorimetric energy the capture gamma-rays are differentiated from other sources of gamma rays. The preliminary results for the capture cross sections of 236U are in agreement with the ENDF/B-VI evaluation. The preliminary results for 234U lower are than ENDF/B-VI evaluation and are closer to older evaluations.

  8. Improved neutron capture cross section of Pu239

    NASA Astrophysics Data System (ADS)

    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 ,?) 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 ,?) measurements on 239Pu. Fission coincidences were measured with a parallel-plate avalanche counter and used to measure the prompt fission ?-ray spectrum in this region to accurately characterize background. The resulting (n ,?) 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.

  9. ACTIVIA: Calculation of Isotope Production Cross-sections and Yields

    E-print Network

    J. J. Back; Y. A. Ramachers

    2008-01-15

    We present a C++ computer package, ACTIVIA, that can calculate target-product cross-sections and the production and decay yields of isotopes from cosmic ray activation using data tables and semi-empirical formulae. We describe the structure and user interface of the computer code as well as provide comparisons between the calculations and experimental results. We also outline suggestions on how the code can be improved and extended for other applications.

  10. Neutrino and Antineutrino Cross sections at MiniBooNE

    SciTech Connect

    Dharmapalan, Ranjan; /Alabama U.

    2011-10-01

    The MiniBooNE experiment has reported a number of high statistics neutrino and anti-neutrino cross sections -among which are the charged current quasi-elastic (CCQE) and neutral current elastic (NCE) neutrino scattering on mineral oil (CH2). Recently a study of the neutrino contamination of the anti-neutrino beam has concluded and the analysis of the anti-neutrino CCQE and NCE scattering is ongoing.

  11. Top quark pair production cross section at the Tevatron

    SciTech Connect

    Cortiana, Giorgio; /INFN, Padua /Padua U.

    2008-04-01

    Top quark pair production cross section has been measured at the Tevatron by CDF and D0 collaborations using different channels and methods, in order to test standard model predictions, and to search for new physics hints affecting the t{bar t} production mechanism or decay. Measurements are carried out with an integrated luminosity of 1.0 to 2.0 fb{sup -1}, and are found to be consistent with standard model expectations.

  12. 13. Photocopy of drawing dated January 20, 1958, CROSS SECTION, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Photocopy of drawing dated January 20, 1958, CROSS SECTION, REHABILITATION OF PIERSHED AT FOOT OF 29TH ST. city of New York Department of Marine and Aviation, Contract 3049, Drawing 3. (On file, City of New York Department of Ports and Trade). - South Brooklyn Freight Terminal, 29th Street Pier, Opposite end of Twenty-ninth Street on upper New York Bay, Brooklyn, Kings County, NY

  13. Cross-sectional transmission electron microscopy of semiconductors

    SciTech Connect

    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/sup +/ 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.

  14. Radial Eigenmodes for a Toroidal Waveguide with Rectangular Cross Section

    SciTech Connect

    Rui Li

    2012-07-01

    In applying mode expansion to solve the CSR impedance for a section of toroidal vacuum chamber with rectangular cross section, we identify the eigenvalue problem for the radial eigenmodes which is different from that for cylindrical structures. In this paper, we present the general expressions of the radial eigenmodes, and discuss the properties of the eigenvalues on the basis of the Sturm-Liouville theory.

  15. Workshop on a Cross Section of Archean Crust

    NASA Technical Reports Server (NTRS)

    Ashwal, L. D. (editor); Card, K. D. (editor)

    1983-01-01

    Various topics relevant to crustal genesis, especially the relationship between Archean low - and high-grade terrains, were discussed. The central Superior Province of the Canadian Shield was studied. Here a 120 km-wide transition from subgreenschist facies rocks of the Michipicoten greenstone belt to granulite facies rocks of the Kapuskasing structural zone represents an oblique cross section through some 20 km of crust, uplifted along a northwest-dipping thrust fault.

  16. Top-Quark Cross Section and Properties at the Tevatron

    SciTech Connect

    Wagner, Wolfgang; /Wuppertal U.

    2009-09-01

    At the Tevatron, the collider experiments CDF and D0 have data sets at their disposal that compromise several hundreds of reconstructed top-antitop-quark pairs and allow for precision measurements of the cross section and production and decay properties. Besides comparing the measurements to standard model predictions, these data sets open a window to physics beyond the standard model. Dedicated analyses look for new heavy gauge bosons, fourth generation quarks, and flavor-changing neutral currents.

  17. Cross-section data for selected Puerto Rico streams

    USGS Publications Warehouse

    Colon-Dieppa, Eloy; Gonzalez, Ralph

    1978-01-01

    The data presented are for delineating the inundation which could be expected by floods of selected magnitudes in Puerto Rico. These cross section data can be used in Flood Insurance Administration studies and in other studies related to the planning, development, and management of flood plains. The data were collected by the Caribbean District of the Water Resources Division of the U.S. Geological Survey in cooperation with the Puerto Rico Department of Natural Resources. (Woodard-USGS)

  18. L-X-ray production cross sections by positrons

    NASA Astrophysics Data System (ADS)

    Mukoyama, Takeshi; T?kési, Károly; Nagashima, Yasuyuki

    2014-11-01

    The L-shell X-ray production cross sections for Ag, In and Sn by positron impact have been calculated with two methods based on classical mechanics, i.e. the binary-encounter approximation and the classical trajectory Monte Carlo method. The results are compared with the experimental data and quantum mechanical calculations. We found that both classical treatments describe the inner-shell ionization processes by positron impact reasonably well.

  19. Neutron Cross-Section Measurements on Structural Materials at ORELA

    SciTech Connect

    Guber, Klaus H; Koehler, Paul; Wiarda, Dorothea; Harvey, John A

    2011-01-01

    Neutron capture experiments, using isotopically enriched and natural samples of chromium and titanium, were performed on flight paths 6 and 7 at the 40 m flight station of ORELA. The experimental data were acquired using a pair of deuterated benzene detectors employing the now well-established pulse-height-weighting technique. These data were complemented by new total cross-section measurements where no useful previous data were available.

  20. W and Z cross sections at the Tevatron

    SciTech Connect

    T. Dorigo

    2003-07-01

    The CDF and D0 experiments at the Tevatron have used p{bar p} collisions at {radical}s = 1.96 TeV to measure the cross section of W and Z boson production using several leptonic final states. An indirect measurement of the total W width has been extracted, and the lepton charge asymmetry in Drell-Yan production has been studied up to invariant masses of 600 GeV/c{sup 2}.

  1. Cross-section studies of light exotic nuclei

    SciTech Connect

    Cortina-Gil, D.; Suemmerer, K.; Baumann, T.; Geissel, H.

    1998-12-21

    Production cross-sections for some exotic fragments produced in the reaction {sup 40}Ar+Be at 1000 MeV/nucleon have been studied. These data, together with new available data at higher projectile Z, and with new data for the same reaction at lower energies, allowed a revision of the semi-empirical EPAX formula. A discussion of some of the improvements introduced in this semi-empirical parameterization will be presented in this contribution.

  2. New Fission Cross Section Measurements using a Time Projection Chamber

    NASA Astrophysics Data System (ADS)

    Sadler, Michael

    2008-03-01

    A group of six universities (ACU, California Polytechnic, Colorado School of Mines, Georgia Institute of Technology, Ohio, and Oregon State) and three national laboratories (Los Alamos, Lawrence Livermore, and Idaho) have undertaken the task of building a Time Projection Chamber (TPC) to measure the fission cross sections needed for the next generation of nuclear reactors. The fission TPC concept will be presented, and why we think we can improve on 50 years of fission study.

  3. High cross-section orbital retroreflector array design and testing

    NASA Astrophysics Data System (ADS)

    Baer, J. W.

    1992-11-01

    The Relay Mirror Experiment (RME) required continuous illumination of its satellite by ground-based lasers. To maintain tracking, the system relied on an array of six-inch diameter hollow retroreflectors, mounted on the lower deck of the spacecraft. The retroreflectors are tailored to the mission, including compensation for their orbital velocity. The array has a lidar cross-section of up to 3000 sq km. This paper describes the design, construction, testing, and use of this retroreflector array.

  4. Airborne laser acquisition of cross-section data

    NASA Technical Reports Server (NTRS)

    Collins, J. G.; Krabill, W. B.

    1980-01-01

    The feasibility of obtaining cross-section data from airborne remote sensing systems is investigated. Eleven test profiles in the Wolf River Basin, near Memphis, Tennessee, are selected. Each profile is characterized using conventional ground survey methods; under 'leaves-off' conditions, photogrammetric, airborne laser, and airborne radar data are obtained. Results indicate that valley profiles can be accurately characterized with an airborne laser system.

  5. Radar cross-sectional study using noise radar

    NASA Astrophysics Data System (ADS)

    Freundorfer, A. P.; Siddiqui, J. Y.; Antar, Y. M. M.

    2015-05-01

    A noise radar system is proposed with capabilities to measure and acquire the radar cross-section (RCS) of targets. The proposed system can cover a noise bandwidth of near DC to 50 GHz. The noise radar RCS measurements were conducted for selective targets like spheres and carpenter squares with and without dielectric bodies for a noise band of 400MHz-5000MHz. The bandwidth of operation was limited by the multiplier and the antennae used.

  6. Differential collision cross-sections for atomic oxygen

    NASA Technical Reports Server (NTRS)

    Torr, Douglas G.

    1991-01-01

    Differential collision cross-sections of O on N2 and other gases were measured to understand vehicle-environmental contamination effects in orbit. The following subject areas are also covered: groundbased scientific observations of rocket releases during NICARE-1; data compression study for the UVI; science priorities for UV imaging in the mid-1990's; and assessment of optimizations possible in UV imaging systems.

  7. Neutron-Induced Cross Sections Measurements of Calcium

    SciTech Connect

    Guber, Klaus H; Kopecky, S.; Schillebeeckx, P.; Kauwenberghs, K.; Siegler, P.

    2013-01-01

    To support the US Department of Energy Nuclear Criticality Safety Program neutron induced cross section experiments were performed at the Geel Electron Linear Accelerator of the Institute for Reference Material and Measurements of the Joint Research Centers, European Union. Neutron capture and transmission measurements were carried out using a metallic calcium sample. The obtained data will be used for a new calcium evaluation, which will be submitted with its covariances to the ENDBF/B nuclear data base.

  8. 30. Photograph of a line drawing. 'CROSS SECTION OF PART ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. Photograph of a line drawing. 'CROSS SECTION OF PART III, SECTION 1, EQUIPMENT LAYOUT, BUILDINGS D-1 TO D-10 INCL., NITRATION, MANUFACTURING AREA, PLANT 'B'.' From U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (Nashville, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  9. 42. Photograph of a line drawing. 'CROSS SECTION AND PLAN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    42. Photograph of a line drawing. 'CROSS SECTION AND PLAN LAYOUT OF PART I, SECTION 8, BUILDINGS NO. H-1 TO H-10 INCL., GRINDING, MANUFACTURING AREA, PLANT B AS OF 4-24-44.' From the U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (NashVille, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  10. 34. Photograph of a line drawing. 'CROSS SECTION AND PLAN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    34. Photograph of a line drawing. 'CROSS SECTION AND PLAN LAYOUT OF PART I, SECTION B, BUILDINGS NO. E-1 TO E-10 INCL., WASHING, MANUFACTURING AREA, PLANT B AS OF 4-24-44.' From the U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (Nashville, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  11. 35. Photograph of a line drawing. 'CROSS SECTION OF PART ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. Photograph of a line drawing. 'CROSS SECTION OF PART III, SECTION 1, EQUIPMENT LAYOUT, BUILDINGS E-1 TO E-10 INCL., WASHING, MANUFACTURING AREA, PLANT 'B'.' From the U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (Nashville, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  12. 29. Photograph of a line drawing. 'CROSS SECTION AND PLAN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. Photograph of a line drawing. 'CROSS SECTION AND PLAN LAYOUT OF PART I, SECTION 8, BUILDINGS NO. D-1 TO D-10 INCL., NITRATION, MANUFACTURING AREA, PLANT B AS OF 4-24-44.' From the U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (Nashville, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  13. Inclusive jet cross-section measurement at CDF

    SciTech Connect

    Norniella, Olga; /Barcelona, IFAE

    2007-05-01

    The CDF Collaboration has measured the inclusive jet cross section using 1992-93 collider data at 1.8 TeV. The CDF measurement is in very good agreement with NLO QCD predictions for transverse energies (E{sub T}) below 200 GeV. However, it is systematically higher than NLO QCD predictions for E{sub T} above 200 GeV.

  14. Top Quark Production Cross Section at the Tevatron

    SciTech Connect

    Shabalina, E.; /Chicago U.

    2006-05-01

    An overview of the preliminary results of the top quark pair production cross section measurements at a center-of-mass energy of 1.96 TeV carried out by the CDF and D0 collaborations is presented. The data samples used for the analyses are collected in the current Tevatron run and correspond to an integrated luminosity from 360 pb{sup -1} up to 760 pb{sup -1}.

  15. Measuring the JPsi-Nucleon dissociation cross section with PANDA

    E-print Network

    Paul Bühler

    2011-09-18

    With the PANDA detector at the HESR at FAIR it will be possible to study the production and absorption of charmed hadrons in nuclear targets. Of special interest in this context is the determination of the JPsi-nucleon dissociation cross section. This can be determined with measurements of the JPsi yield in antiproton-nucleus reactions using different target materials. The experiment is described and numerical simulations are presented.

  16. Radar cross section measurements of a scale model of the space shuttle orbiter vehicle

    NASA Technical Reports Server (NTRS)

    Yates, W. T.

    1978-01-01

    A series of microwave measurements was conducted to determine the radar cross section of the Space Shuttle Orbiter vehicle at a frequency and at aspect angles applicable to re-entry radar acquisition and tracking. The measurements were performed in a microwave anechoic chamber using a 1/15th scale model and a frequency applicable to C-band tracking radars. The data were digitally recorded and processed to yield statistical descriptions useful for prediction of orbiter re-entry detection and tracking ranges.

  17. Kuang's Semi-Classical Formalism for Calculating Electron Capture Cross Sections: A Space- Physics Application

    NASA Technical Reports Server (NTRS)

    Barghouty, A. F.

    2014-01-01

    Accurate estimates of electroncapture cross sections at energies relevant to the modeling of the transport, acceleration, and interaction of energetic neutral atoms (ENA) in space (approximately few MeV per nucleon) and especially for multi-electron ions must rely on detailed, but computationally expensive, quantum-mechanical description of the collision process. Kuang's semi-classical approach is an elegant and efficient way to arrive at these estimates. Motivated by ENA modeling efforts for apace applications, we shall briefly present this approach along with sample applications and report on current progress.

  18. Fusion, reaction, and breakup cross sections of {sup 9}Be on a light mass target

    SciTech Connect

    Marti, G.V.; Capurro, O.A.; Pacheco, A.J.; Testoni, J.E.; Ramirez, M.; Arazi, A.; Gomes, P.R.S.; Padron, I.; Anjos, R.M.; Lubian, J.; Crema, E.

    2005-02-01

    The total fusion cross section for the {sup 9}Be+{sup 27}Al system has been measured at energies close and above the Coulomb barrier. Reaction cross sections for this system were derived from elastic scattering data, and the breakup-plus-transfer-channel cross sections were estimated from the difference between these data and measured cross-section fusion.

  19. Hydrogen and Nitrogen Broadened Ethane and Propane Absorption Cross Sections

    NASA Astrophysics Data System (ADS)

    Hargreaves, Robert J.; Appadoo, Dominique; Billinghurst, Brant E.; Bernath, Peter F.

    2015-06-01

    High-resolution infrared absorption cross sections are presented for the ?9 band of ethane (C2H6) at 823 cm-1. These cross sections make use of spectra recorded at the Australian Synchrotron using a Fourier transform infrared spectrometer with maximum resolution of 0.00096 cm-1. The spectra have been recorded at 150, 120 and 90 K for hydrogen and nitrogen broadened C2H6. They cover appropriate temperatures, pressures and broadening gases associated with the atmospheres of the Outer Planets and Titan, and will improve atmospheric retrievals. The THz/Far-IR beamline at the Australian Synchrotron is unique in combining a high-resolution Fourier transform spectrometer with an 'enclosive flow cooling' (EFC) cell designed to study molecules at low temperatures. The EFC cell is advantageous at temperatures for which the vapor pressure is very low, such as C2H6 at 90 K. Hydrogen broadened absorption cross sections of propane between 700 and 1200 cm-1 will also be presented based on spectra obtained at the Canadian Light Source.

  20. Froissart Bound on Inelastic Cross Section Without Unknown Constants

    E-print Network

    Martin, André

    2015-01-01

    Assuming that axiomatic local field theory results hold for hadron scattering, Andr\\'e Martin and S. M. Roy recently obtained absolute bounds on the D-wave below threshold for pion-pion scattering and thereby determined the scale of the logarithm in the Froissart bound on total cross sections in terms of pion mass only. Previously, Martin proved a rigorous upper bound on the inelastic cross-section $\\sigma_{inel}$ which is one-fourth of the corresponding upper bound on $\\sigma_{tot}$, and Wu, Martin,Roy and Singh improved the bound by adding the constraint of a given $\\sigma_{tot}$. Here we use unitarity and analyticity to determine, without any high energy approximation, upper bounds on energy averaged inelastic cross sections in terms of low energy data in the crossed channel. These are Froissart-type bounds without any unknown coefficient or unknown scale factors and can be tested experimentally. Alternatively, their asymptotic forms,together with the Martin-Roy absolute bounds on pion-pion D-waves below t...

  1. Hydraulic geometry of river cross sections; theory of minimum variance

    USGS Publications Warehouse

    Williams, Garnett P.

    1978-01-01

    This study deals with the rates at which mean velocity, mean depth, and water-surface width increase with water discharge at a cross section on an alluvial stream. Such relations often follow power laws, the exponents in which are called hydraulic exponents. The Langbein (1964) minimum-variance theory is examined in regard to its validity and its ability to predict observed hydraulic exponents. The variables used with the theory were velocity, depth, width, bed shear stress, friction factor, slope (energy gradient), and stream power. Slope is often constant, in which case only velocity, depth, width, shear and friction factor need be considered. The theory was tested against a wide range of field data from various geographic areas of the United States. The original theory was intended to produce only the average hydraulic exponents for a group of cross sections in a similar type of geologic or hydraulic environment. The theory does predict these average exponents with a reasonable degree of accuracy. An attempt to forecast the exponents at any selected cross section was moderately successful. Empirical equations are more accurate than the minimum variance, Gauckler-Manning, or Chezy methods. Predictions of the exponent of width are most reliable, the exponent of depth fair, and the exponent of mean velocity poor. (Woodard-USGS)

  2. Neutron Capture Cross Sections for the Re/Os Clock

    SciTech Connect

    Mosconi, M.; Heil, M.; Kaeppeler, F.; Plag, R.; Voss, F.; Wisshak, K.; Mengoni, A.; Cennini, P.; Chiaveri, E.; Ferrari, A.; Fitzpatrick, L.; Herrera-Martinez, A.; Kadi, Y.; Sarchiapone, L.; Vlachoudis, V.; Wendler, H.; Aerts, G.; Andriamonje, S.; Berthoumieux, E.; Dridi, W.

    2005-05-24

    The radioactive decay of 187Re {yields} 187Os (t1/2 = 43 Gyr) is suited for dating the onset of heavy-element nucleosynthesis. The radiogenic contribution to the 187Os abundance is the difference between the natural abundance and the corresponding s-process component. This component can be obtained via the well-established {sigma}N systematics using the neighboring s-only isotope 186Os, provided the neutron-capture cross sections of both isotopes are known with sufficient accuracy. We report on a new set of experiments performed with a C6D6 detector array at the n{sub T}OF neutron spallation facility of CERN. The capture cross sections of 186Os, 187Os, and 188Os have been measured in the neutron-energy range between 1 eV and 1 MeV, and Maxwellian-averaged cross sections were deduced for the relevant thermal energies from kT=5 keV to 100 keV.

  3. Detecting Neutrinos from AGN: New Fluxes and Cross Sections

    E-print Network

    Gary C. Hill

    1996-07-28

    New information on the structure of the nucleon from the HERA ep collider leads to higher neutrino cross sections for the processes nu_mu + N --> mu + X needed to calculate the expected rates of astrophysical neutrino induced muons in large detectors either under construction, or in the design stage. These higher cross sections lead to higher muon rates for arrival angles where neutrino attenuation in the earth is less important. On the other hand, new estimates of AGN neutrino fluxes suggest that the expected muon rates in these detectors may be much lower than previously calculated. I use the new cross sections to calculate the expected muon rates and angular distributions in large detectors for a variety of AGN models and compare these rates with the atmospheric neutrino backrounds (from both conventional decay channels and the "prompt" charmed meson decay channels). If the lowest flux estimates are correct, there may be diffculties in determining the origin of a small excess of muons, due to the large uncertainty in the rate of the charmed meson neutrino production channel. However, the more optimistic AGN neutrino fluxes should be detectable in proposed detectors, such as DUMAND-II, AMANDA, NESTOR and Lake Baikal.

  4. Summary of the Workshop on Neutron Cross Section Covariances

    SciTech Connect

    Smith, Donald L.

    2008-12-15

    A Workshop on Neutron Cross Section Covariances was held from June 24-27, 2008, in Port Jefferson, New York. This Workshop was organized by the National Nuclear Data Center, Brookhaven National Laboratory, to provide a forum for reporting on the status of the growing field of neutron cross section covariances for applications and for discussing future directions of the work in this field. The Workshop focused on the following four major topical areas: covariance methodology, recent covariance evaluations, covariance applications, and user perspectives. Attention was given to the entire spectrum of neutron cross section covariance concerns ranging from light nuclei to the actinides, and from the thermal energy region to 20 MeV. The papers presented at this conference explored topics ranging from fundamental nuclear physics concerns to very specific applications in advanced reactor design and nuclear criticality safety. This paper provides a summary of this workshop. Brief comments on the highlights of each Workshop contribution are provided. In addition, a perspective on the achievements and shortcomings of the Workshop as well as on the future direction of research in this field is offered.

  5. A study of radar cross section measurement techniques

    NASA Technical Reports Server (NTRS)

    Mcdonald, Malcolm W.

    1986-01-01

    Past, present, and proposed future technologies for the measurement of radar cross section were studied. The purpose was to determine which method(s) could most advantageously be implemented in the large microwave anechoic chamber facility which is operated at the antenna test range site. The progression toward performing radar cross section measurements of space vehicles with which the Orbital Maneuvering Vehicle will be called upon to rendezvous and dock is a natural outgrowth of previous work conducted in recent years of developing a high accuracy range and velocity sensing radar system. The radar system was designed to support the rendezvous and docking of the Orbital Maneuvering Vehicle with various other space vehicles. The measurement of radar cross sections of space vehicles will be necessary in order to plan properly for Orbital Maneuvering Vehicle rendezvous and docking assignments. The methods which were studied include: standard far-field measurements; reflector-type compact range measurements; lens-type compact range measurement; near field/far field transformations; and computer predictive modeling. The feasibility of each approach is examined.

  6. An overview of relativistic distorted-wave cross sections

    SciTech Connect

    Fontes, C. J.; Zhang, H. L.; Abdallah, J.

    2004-01-01

    Over the past twenty years significant progress has been made in calculating the vast amounts of relativistic atomic data that are required to model heavy element, non-LTE plasmas. A number of the relevant processes, including electron-impact excitation, photoionization, autoionization and electron-impact ionization, involve the computation of continuum electron wavefunctions. If the plasma consists of ions with sufficiently high charge, then the distorted-wave approximation is valid and can be used to compute these continuum orbitals and the corresponding cross sections. An overview of the relativistic distorted-wave approach is provided with an aim toward underscoring the similarities and differences with the longer established, nonrelativistic and semi-relativistic approaches. An example for extending the distorted-wave approach to less highly charged systems via the inclusion of resonance contributions to the cross sections is provided. Related topics, such as the top-up contribution, the high energy (Bethe) cross section limit, the Breit and Moller interactions, and transitions among magnetic sublevels are also discussed.

  7. Evaluation of discrepancies in assembly cross-section generator codes

    SciTech Connect

    Fisher, J.R.; Grow, R.L.; Rapp, J.S.; Smolinske, K.M.; Mint, L.S. )

    1990-02-01

    The capabilities of utility reactor analysis technical staffs have increased significantly over the past five to ten years. Utilities utilize different cross section generators (EPRI-CELL, CPM, CASMO), different versions of these generators and different libraries in the generators, to produce input to different nodal codes. Phase I of this project utilized available data from utility calculations to identify the areas of differences in calculated results and to make an initial assessment of the potential impact and/or consequence of these differences. Phase II of this project investigated these differences via a consortium of utilities performing calculations for pin cells and multi-pin cells using controlled input data and options. The Phase II goal was to quantify differences and to determine if the differences were due to cross section library, cross section code methodology or the procedure for utilizing a code. The Phase III goal was to investigate the significant differences from Phase II in an assembly environment to determine if the differences became smaller, larger or remained the same in the assembly environment. The Phase III assembly calculations were performed by the same group of utilities as Phase II and the cases used controlled input and code vendor input option recommendations. 10 figs., 31 tabs.

  8. Fully hadronic ttbar cross section measurement with ATLAS detector

    E-print Network

    Claudia Bertella

    2011-11-16

    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 final state and the state-of-the-art of the b-jet trigger performance estimation are presented in this contribution.

  9. Photonuclear Reactions in FLUKA: Cross Sections and Interaction Models

    SciTech Connect

    Fasso, Alberto; Ferrari, Alfredo; Sala, Paola R.

    2005-05-24

    Photonuclear reactions, implemented in FLUKA about ten years ago, have opened the way to a more accurate design of electron accelerator shielding. Since then, they have been introduced also in other codes: but the FLUKA design, covering all nuclei over the whole energy range, remains still unique. The FLUKA scheme is based on several physical models corresponding to different energy ranges but partially overlapping to ensure continuity. All models are smoothly integrated in the FLUKA hadronic event generator. Here we will mainly focus on the FLUKA Giant Resonance total cross-section database, which has been derived from experimental data or from existing evaluations for 190 nuclides. For all other nuclei, excitation functions are obtained from parameterizations or by interpolation. Many partial cross sections, not used explicitly in FLUKA, have also been evaluated in order to ensure consistency of the total cross sections entered into the database. The FLUKA implementation of photonuclear reactions has been successfully benchmarked with activation and neutron spectrometry experiments, and is being widely used to design shielding and to predict radiation damage.

  10. ^241Am(n,?) absolute cross sections measured with DANCE

    NASA Astrophysics Data System (ADS)

    Jandel, M.; Bredeweg, T. A.; Fowler, M. M.; Bond, E. M.; Chadwick, M. B.; Clement, R. R.; Couture, A.; O'Donnell, J. M.; Reifarth, R.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Agvaanluvsan, U.; Macri, R. A.; Sheets, S. A.; Wu, C. Y.; Becker, J. A.

    2007-10-01

    ^241Am is present in plutonium due to the beta decay of ^241Pu (t1/2=14.38 years). As such ^241Am can be used as a detector for nuclear forensics. A precise measurement of ^241Am(n,?) cross section is thus needed for this application. The measurement is also of interest for advanced reactor design as part of the Global Nuclear Energy Partnership (GNEP). The Detector for Advanced Neutron Capture Experiments (DANCE) at Los Alamos National Laboratory (LANL) was used for neutron capture cross section measurement on ^241Am. The high granularity of DANCE (160 BaF2 detectors in a 4? geometry) enables the efficient detection of prompt gamma-rays following a neutron capture. DANCE is located on the 20.26 m neutron flight path 14(FP14) at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center (LANSCE). The absolute ^241Am(n,?) cross sections were obtained in the range of neutron energies from 0.02 eV to 320 keV. The results will be compared to existing evaluations in detail.

  11. CMB Constraints On The Thermal WIMP Annihilation Cross Section

    E-print Network

    Steigman, Gary

    2015-01-01

    A thermal relic, often referred to as a weakly interacting massive particle (WIMP),is a particle produced during the early evolution of the Universe whose relic abundance (e.g., at present) depends only on its mass and its thermally averaged annihilation cross section (annihilation rate factor) sigma*v_ann. Late time WIMP annihilation has the potential to affect the cosmic microwave background (CMB) power spectrum. Current observational constraints on the absence of such effects provide bounds on the mass and the annihilation cross section of relic particles that may, but need not be dark matter candidates. For a WIMP that is a dark matter candidate, the CMB constraint sets an upper bound to the annihilation cross section, leading to a lower bound to their mass that depends on whether or not the WIMP is its own antiparticle. For a self-conjugate WIMP, m_min = 50f GeV, where f is an electromagnetic energy efficiency factor. For a non self-conjugate WIMP, the minimum mass is a factor of two larger. For a WIMP t...

  12. Extension of the Bgl Broad Group Cross Section Library

    NASA Astrophysics Data System (ADS)

    Kirilova, Desislava; Belousov, Sergey; Ilieva, Krassimira

    2009-08-01

    The broad group cross-section libraries BUGLE and BGL are applied for reactor shielding calculation using the DOORS package based on discrete ordinates method and multigroup approximation of the neutron cross-sections. BUGLE and BGL libraries are problem oriented for PWR or VVER type of reactors respectively. They had been generated by collapsing the problem independent fine group library VITAMIN-B6 applying PWR and VVER one-dimensional radial model of the reactor middle plane using the SCALE software package. The surveillance assemblies (SA) of VVER-1000/320 are located on the baffle above the reactor core upper edge in a region where geometry and materials differ from those of the middle plane and the neutron field gradient is very high which would result in a different neutron spectrum. That is why the application of the fore-mentioned libraries for the neutron fluence calculation in the region of SA could lead to an additional inaccuracy. This was the main reason to study the necessity for an extension of the BGL library with cross-sections appropriate for the SA region. Comparative analysis of the neutron spectra of the SA region calculated by the VITAMIN-B6 and BGL libraries using the two-dimensional code DORT have been done with purpose to evaluate the BGL applicability for SA calculation.

  13. From ZZ to ZH : How Low Can These Cross Sections Go or Everybody, Let's Cross Section Limbo!

    SciTech Connect

    Strauss, Emanuel Alexandre; /SUNY, Stony Brook

    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{sup -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{sup -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.

  14. Evidence of concentration dependence of the two-photon absorption cross section: Determining the "true" cross section value

    NASA Astrophysics Data System (ADS)

    Ajami, Aliasghar; Gruber, Peter; Tromayer, Maximilian; Husinsky, Wolfgang; Stampfl, Jürgen; Liska, Robert; Ovsianikov, Aleksandr

    2015-09-01

    The two-photon absorption (2PA) phenomenon is the basis of many unique applications involving suitable chromophores as photoinitiators. Ideally the 2PA cross section should, therefore, be a unique parameter, allowing quantification and comparing 2PA capabilities of different substances. In this report, the most straightforward and widespread method, the Z-scan technique, was used for determining the 2PA cross-section values of three different synthesized photoinitiators and one laser dye as a standard. It is demonstrated that the experimentally obtained values strongly depend on the molar concentration of a measured solution. A tenfold decrease in substance concentration can lead to the doubling of the 2PA cross-section. A similar concentration dependence was confirmed for all three investigated substances. Among the crucial implications of this observed behavior is the questionable possibility to compare the 2PA characteristics of different compounds based on the values reported in the literature. An example of another important consequence of this effect extends i.e. to the calculation of the dose necessary for killing the tumor cells in 2PA-based photodynamic therapy applications. The possible factors responsible for this contra-intuitive behavior are discussed and investigated. Finally, a reliable measurement protocol for comprehensive characterization of 2PA capability of different substances is proposed. Herewith an attempt to establish a standard method, which takes into account the concentration dependence, is made. This method provides means for faultless comparison of different compounds.

  15. TELOMERE SHORTENING IN A LONG-LIVED MARINE BIRD: CROSS-SECTIONAL ANALYSIS AND TEST OF AN AGING TOOL

    E-print Network

    Vleck, Carol

    775 TELOMERE SHORTENING IN A LONG-LIVED MARINE BIRD: CROSS-SECTIONAL ANALYSIS AND TEST OF AN AGING length of telomere restriction fragments (TRFs) and age has recently been demonstrated in several bird, it has been shown that telomere rate-of-change (TROC) correlates tightly with life span across several

  16. Cross-section measurement of the Ba130(p,?)La131 reaction for ?-process nucleosynthesis

    NASA Astrophysics Data System (ADS)

    Netterdon, L.; Endres, A.; Kiss, G. G.; Mayer, J.; Rauscher, T.; Scholz, P.; Sonnabend, K.; Török, Zs.; Zilges, A.

    2014-09-01

    Background: Deviations between experimental data of charged-particle-induced reactions and calculations within the statistical model are frequently found. An extended data base is needed to address the uncertainties regarding the nuclear-physics input parameters in order to understand the nucleosynthesis of the neutron-deficient p nuclei. Purpose: A measurement of total cross-section values of the Ba130(p,?)La131 reaction at low proton energies allows a stringent test of statistical model predictions with different proton+nucleus optical model potentials. Since no experimental data are available for proton-capture reactions in this mass region around A ?130, this measurement can be an important input to test the global applicability of proton+nucleus optical model potentials. Method: The total reaction cross-section values were measured by means of the activation method. After the irradiation with protons, the reaction yield was determined by use of ?-ray spectroscopy using two clover-type high-purity germanium detectors. In total, cross-section values for eight different proton energies could be determined in the energy range between 3.6 MeV ?Ep? 5.0 MeV, thus, inside the astrophysically relevant energy region. Results: The measured cross-section values were compared to Hauser-Feshbach calculations using the statistical model codes TALYS and SMARAGD with different proton+nucleus optical model potentials. With the semimicroscopic JLM proton+nucleus optical model potential used in the SMARAGD code, the absolute cross-section values are reproduced well, but the energy dependence is too steep at the lowest energies. The best description is given by a TALYS calculation using the semimicroscopic Bauge proton+nucleus optical model potential using a constant renormalization factor. Conclusions: The statistical model calculation using the Bauge semimicroscopic proton+nucleus optical model potential deviates by a constant factor of 2.1 from the experimental data. Using this model, an experimentally supported stellar reaction rate for proton capture on the p nucleus Ba130 was calculated. At astrophysical temperatures, an increase in the stellar reaction rate of 68% compared to rates obtained from the widely used NON-SMOKER code is found. This measurement extends the scarce experimental data base for charged-particle-induced reactions, which can be helpful to derive a more globally applicable proton+nucleus optical model potential.

  17. Reducing cross-sectional data using a genetic algorithm method and effects on cross-section geometry and steady-flow profiles

    USGS Publications Warehouse

    Berenbrock, Charles E.

    2015-01-01

    The effects of reduced cross-sectional data points on steady-flow profiles were also determined. Thirty-five cross sections of the original steady-flow model of the Kootenai River were used. These two methods were tested for all cross sections with each cross section resolution reduced to 10, 20 and 30 data points, that is, six tests were completed for each of the thirty-five cross sections. Generally, differences from the original water-surface elevation were smaller as the number of data points in reduced cross sections increased, but this was not always the case, especially in the braided reach. Differences were smaller for reduced cross sections developed by the genetic algorithm method than the standard algorithm method.

  18. Macroscopic cross section generation and application for coupled spatial kinetics and thermal hydraulics analysis with SAS-DIF3DK

    SciTech Connect

    Turski, R.B.; Morris, E.E.; Taiwo, T.A.; Cahalan, J.E.

    1997-08-01

    This paper discusses the importance of modeling the transient behavior of multigroup cross sections in the context of coupled reactor physics and thermal-hydraulic computations with the SAS-DIF3DK computer code. The MACOEF macroscopic cross section methodology is presented. Results from benchmark verification calculations with a continuous-energy Monte Carlo are reported. Analysis of the Chernobyl accident is made using correlated WIMS-D4M generated group constants with special emphasis placed on the impact of modeling assumptions on the progression of the accident simulation.

  19. Which Language Declines More? Longitudinal versus Cross-Sectional Decline of Picture Naming in Bilinguals with Alzheimer’s Disease

    PubMed Central

    Ivanova, Iva; Salmon, David P.; Gollan, Tamar H.

    2014-01-01

    In this study, we investigated dual-language decline in non-balanced bilinguals with probable Alzheimer’s Disease (AD) both longitudinally and cross-sectionally. We examined patients’ naming accuracy on the Boston Naming Test (BNT: Kaplan et al., 1983) over three testing sessions (longitudinal analysis) and compared their performance to that of matched controls (cross-sectional analysis). We found different longitudinal and cross-sectional patterns of decline: Longitudinally, the non-dominant language seemed to decline more steeply than the dominant language, but, cross-sectionally, differences between patients and controls were larger for the dominant than for the non-dominant language, especially at the initial testing session. This differential pattern of results for cross-sectional versus longitudinal decline was supported by correlations between decline measures and BNT item characteristics. Further studies will be needed to better characterize the nature of linguistic decline in bilinguals with AD; however, these results suggest that representational robustness of individual lexical representations, rather than language membership, might determine the time course of decline for naming in bilinguals with AD. PMID:24725624

  20. Cross-section calculations for electron scattering from ketene in low energies using R-matrix method

    NASA Astrophysics Data System (ADS)

    Wang, Kedong; Meng, Ju; Liu, Yufang; Sun, Jinfeng

    2015-08-01

    We report on a computational investigation of electron scattering by ketene in the correlated and uncorrelated approximations using the R-matrix method for energies ranging from 0 to 10 eV. The target wave functions are based on different-size basis sets and are tested to obtain the reliable properties of electronic states for the ketene molecule. The calculated elastic integral cross sections present two low-lying ?* shape resonances belonging to 2B1 and 2B2 symmetries. Two higher-lying resonances of 2B1 symmetry, one core-excited shape resonance and one Feshbach resonance, are detected in the excitation cross sections. These resonances are in agreement with the available data in the literature. The Born correction is used to obtain converged cross sections for the L > 4 partial waves excluded from the R-matrix calculations. We compare the elastic cross sections with the available data for CO2. The effective collision frequencies over a wide electron temperature range (100-30 000 K) are calculated using the data of the momentum-transfer cross section.

  1. Radioactive targets for neutron-induced cross section measurements

    SciTech Connect

    Kronenberg, A.; Bond, E. M.; Glover, S. E.; Rundberg, R. S.; Vieira, D. J.; Esch, E. I.; Reifarth, R.; Ullmann, J. L.; Haight, Robert C.; Rochmann, D.

    2004-01-01

    Measurements using radioactive targets are important for the determination of key reaction path ways associated with the synthesis of the elements in nuclear astrophysics (sprocess), advanced fuel cycle initiative (transmutation of radioactive waste), and stockpile stewardship. High precision capture cross-section measurements are needed to interpret observations, predict elemental or isotopical ratios, and unobserved abundances. There are two new detector systems that are presently being commissioned at Los Alamos National Laboratory for very precise measurements of (n,{gamma}) and (n,f) cross-sections using small quantities of radioactive samples. DANCE (Detector for Advanced Neutron-Capture Experiments), a 4 {pi} gamma array made up of 160 BaF{sub 2} detectors, is designed to measure neutron capture cross-sections of unstable nuclei in the low-energy range (thermal to {approx}500 keV). The high granularity and high detection efficiency of DANCE, combined with the high TOF-neutron flux available at the Lujan Center provides a versatile tool for measuring many important cross section data using radioactive and isotopically enriched targets of about 1 milligram. Another powerful instrument is the Lead-slowing down spectrometer (LSDS), which will enable the measurement of neutron-induced fission cross-section of U-235m and other short-lived actinides in a energy range from 1-200 keV with sample sizes down to 10 nanograms. Due to the short half-life of the U-235m isomer (T{sub 1/2} = 26 minutes), the samples must be rapidly and repeatedly extracted from its {sup 239}Pu parent. Since {sup 239}Pu is itself highly fissile, the separation must not only be rapid, but must also be of very high purity (the Pu must be removed from the U with a decontamination factor >10{sup 12}). Once extracted and purified, the {sup 235m}U isomer would be electrodeposited on solar cells as a fission detector and placed within the LSDS for direct (n,f) cross section measurements. The production of radioactive targets of a few milligrams will be described as well as the containment for safe handling of these targets at the Lujan Center at LANSCE. To avoid any contamination, the targets are electrochemically fixed onto thin Ti foils and two foils are placed back to back to contain the radioactive material within. This target sandwich is placed in a cylinder made of aluminum with thin translucent windows made of Kapton. Actinides targets, such as {sup 234,235,236,238}U, {sup 237}Np, and {sup 239}Pu are prepared by electrodeposition or molecular plating techniques. Target thicknesses of 1-2 mg/cm{sup 2} with sizes of 1 cm{sup 2} or more have been made. Other targets will be fabricated from separation of irradiated isotopically enriched targets, such as {sup 155}Eu from {sup 154}Sm,{sup 171}Tm from {sup 170}Er, and {sup 147}Pm from {sup 146}Nd, which has been irradiated in the high flux reactor at ILL, Grenoble. A radioactive sample isotope separator (RSIS) is in the process of being commissioned for the preparation of other radioactive targets. A brief summary of these experiments and the radioactive target preparation technique will be given.

  2. Hadronic Production of psi(2S) Cross section and Polarization

    SciTech Connect

    Chung, Kwangzoo; /Carnegie Mellon U.

    2008-05-01

    The hadronic production cross section and the polarization of {psi}(2S) meson are measured by using the data from p{bar p} collisions at {radical}s = 1.96 TeV collected by the Collider Detector at Fermilab. The datasets used correspond to integrated luminosity of 1.1 fb{sup -1} and 800 pb{sup -1}, respectively. The decay {psi}(2S) {yields} {mu}{sup +}{mu}{sup -} is used to reconstruct {psi}(2S) mesons in the rapidity range |y({psi}(2S))| < 0.6. The coverage of the p{sub T} range is 2.0 GeV/c {le} p{sub T} ({psi}(2S)) < 30 GeV/c for the cross section analysis and pT {ge} 5 GeV/c for the polarization analysis. For events with p{sub T} ({psi}(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 {psi}(2S) mesons is found to be increasingly longitudinal as p{sub T} increases from 5 GeV/c to 30 GeV/c. The result is compared to contemporary theory models.

  3. Propionaldehyde infrared cross-sections and band strengths

    NASA Astrophysics Data System (ADS)

    Köro?lu, 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.

  4. MOX Cross-Section Libraries for ORIGEN-ARP

    SciTech Connect

    Gauld, I.C.

    2003-07-01

    The use of mixed-oxide (MOX) fuel in commercial nuclear power reactors operated in Europe has expanded rapidly over the past decade. The predicted characteristics of MOX fuel such as the nuclide inventories, thermal power from decay heat, and radiation sources are required for design and safety evaluations, and can provide valuable information for non-destructive safeguards verification activities. This report describes the development of computational methods and cross-section libraries suitable for the analysis of irradiated MOX fuel with the widely-used and recognized ORIGEN-ARP isotope generation and depletion code of the SCALE (Standardized Computer Analyses for Licensing Evaluation) code system. The MOX libraries are designed to be used with the Automatic Rapid Processing (ARP) module of SCALE that interpolates appropriate values of the cross sections from a database of parameterized cross-section libraries to create a problem-dependent library for the burnup analysis. The methods in ORIGEN-ARP, originally designed for uranium-based fuels only, have been significantly upgraded to handle the larger number of interpolation parameters associated with MOX fuels. The new methods have been incorporated in a new version of the ARP code that can generate libraries for low-enriched uranium (LEU) and MOX fuel types. The MOX data libraries and interpolation algorithms in ORIGEN-ARP have been verified using a database of declared isotopic concentrations for 1042 European MOX fuel assemblies. The methods and data are validated using a numerical MOX fuel benchmark established by the Organization for Economic Cooperation and Development (OECD) Working Group on burnup credit and nuclide assay measurements for irradiated MOX fuel performed as part of the Belgonucleaire ARIANE International Program.

  5. Neutron Cross Section Covariances for Structural Materials and Fission Products

    SciTech Connect

    Hoblit, S.; Hoblit,S.; Cho,Y.-S.; Herman,M.; Mattoon,C.M.; Mughabghab,S.F.; Oblozinsky,P.; Pigni,M.T.; Sonzogni,A.A.

    2011-12-01

    We describe neutron cross section covariances for 78 structural materials and fission products produced for the new US evaluated nuclear reaction library ENDF/B-VII.1. Neutron incident energies cover full range from 10{sup -5} eV to 20 MeV and covariances are primarily provided for capture, elastic and inelastic scattering as well as (n,2n). The list of materials follows priorities defined by the Advanced Fuel Cycle Initiative, the major application being data adjustment for advanced fast reactor systems. Thus, in addition to 28 structural materials and 49 fission products, the list includes also {sup 23}Na which is important fast reactor coolant. Due to extensive amount of materials, we adopted a variety of methodologies depending on the priority of a specific material. In the resolved resonance region we primarily used resonance parameter uncertainties given in Atlas of Neutron Resonances and either applied the kernel approximation to propagate these uncertainties into cross section uncertainties or resorted to simplified estimates based on integral quantities. For several priority materials we adopted MF32 covariances produced by SAMMY at ORNL, modified by us by adding MF33 covariances to account for systematic uncertainties. In the fast neutron region we resorted to three methods. The most sophisticated was EMPIRE-KALMAN method which combines experimental data from EXFOR library with nuclear reaction modeling and least-squares fitting. The two other methods used simplified estimates, either based on the propagation of nuclear reaction model parameter uncertainties or on a dispersion analysis of central cross section values in recent evaluated data files. All covariances were subject to quality assurance procedures adopted recently by CSEWG. In addition, tools were developed to allow inspection of processed covariances and computed integral quantities, and for comparing these values to data from the Atlas and the astrophysics database KADoNiS.

  6. Collision cross sections of proteins and their complexes: a calibration framework and database for gas-phase structural biology.

    PubMed

    Bush, Matthew F; Hall, Zoe; Giles, Kevin; Hoyes, John; Robinson, Carol V; Ruotolo, Brandon T

    2010-11-15

    Collision cross sections in both helium and nitrogen gases were measured directly using a drift cell with RF ion confinement inserted within a quadrupole/ion mobility/time-of-flight hybrid mass spectrometer (Waters Synapt HDMS, Manchester, U.K.). Collision cross sections for a large set of denatured peptide, denatured protein, native-like protein, and native-like protein complex ions are reported here, forming a database of collision cross sections that spans over 2 orders of magnitude. The average effective density of the native-like ions is 0.6 g cm(-3), which is significantly lower than that for the solvent-excluded regions of proteins and suggests that these ions can retain significant memory of their solution-phase structures rather than collapse to globular structures. Because the measurements are acquired using an instrument that mimics the geometry of the commercial Synapt HDMS instrument, this database enables the determination of highly accurate collision cross sections from traveling-wave ion mobility data through the use of calibration standards with similar masses and mobilities. Errors in traveling-wave collision cross sections determined for native-like protein complexes calibrated using other native-like protein complexes are significantly less than those calibrated using denatured proteins. This database indicates that collision cross sections in both helium and nitrogen gases can be well-correlated for larger biomolecular ions, but non-correlated differences for smaller ions can be more significant. These results enable the generation of more accurate three-dimensional models of protein and other biomolecular complexes using gas-phase structural biology techniques. PMID:20979392

  7. Guided Surface Plasmon Mode of Semicircular Cross Section Silver Nanoridges

    E-print Network

    Guo, Junpeng

    2012-01-01

    Tightly confined plasmon waveguide modes supported by semicircular cross section top silver nanoridges are investigated in this paper. Mode field profiles, dispersion curves, propagation distances, confinement factors, and figure-of-merits of semicircular top silver nanoridge plasmon waveguide mode are calculated for different radii of curvature at different wavelengths. It is found that semicircular top silver nanoridges support tightly confined quasi-TEM plasmon waveguide modes. Semicircular top silver nanoridge mode has longer propagation distance and higher figure-of-merit than that of the cylindrical silver nanowire of the same radius of curvature.

  8. Comments on high-energy total cross sections in QCD

    NASA Astrophysics Data System (ADS)

    Giordano, Matteo; Meggiolaro, Enrico

    2015-05-01

    We discuss how hadronic total cross sections at high energy depend on the details of QCD, namely on the number of colours Nc and the quark masses. We find that while a "Froissart"-type behaviour ?tot ? Blog2 ? s is rather general, relying only on the presence of higher-spin stable particles in the spectrum, the value of B depends quite strongly on the quark masses. Moreover, we argue that B is of order O (Nc0) at large Nc, and we discuss a bound for B which does not become singular in the Nf = 2 chiral limit, unlike the Froissart-?ukaszuk-Martin bound.

  9. Final Report - Nucelar Astrophysics & Neutron Cross Section Measurements

    SciTech Connect

    Carlton, Robert F

    2009-12-01

    This enduring research program of 28 years has taken advantage of the excellent research facility of ORELA at Oak Ridge National Laboratory. The fruitful collaborations include a number of scientists from ORNL and some from LASL. This program which has ranged from nuclear structure determinations to astrophysical applications has resulted in the identification and/or the refinement of the nuclear properties of more than 5,000 nuclear energy levels or compound energy states. The nuclei range from 30Si to 250Cf, the probes range from thermal to 50 MeV neutrons, and the studies range from capture gamma ray spectra to total and differential scattering and absorption cross sections. Specific target nuclei studied include the following: 120Sn 124Sn 125Sn 113Sn 115Sn 117Sn 119Sn 249Cf 33S 34S 249Bk 186Os 187Os 188Os 30Si 32S 40Ca 48Ca 60Ni 54Fe 86Kr 88Sr 40Ar 122Sn 90Zr 122Sn(n,?) 208Pb 204Pb 52Cr 54Cr 50Cr 53Cr As can be seen, we have studied, on average, more than one isotope per year of grant funding and have focused on exploiting those elements having multiple isotopes in order to investigate systematic trends in nuclear properties, for the purpose of providing more stringent tests of the nuclear spherical optical model with a surface imaginary potential. We have investigated an l-dependence of the real-well depth of the spherical optical model; we have used these measurements to deduce the existence of doorway states in the compound nucleus; and in the total cross section measurements we have, in addition to resonance energies and widths, obtained values for the level density and neutron strength function. Due to the high neutron energy resolution of the ORELA and in some cases the addition of differential scattering cross section data, we have been able to disaggregate the spin states and provide level spacing and strength function for each partial wave in the neutron-nucleus interaction, in some cases up to d5/2. In the following we will summarize the most recent analyses of neutron total cross section measurements, some of which have not been previously reported.

  10. Parton distributions with the combined HERA charm production cross sections

    SciTech Connect

    Bertone, Valerio; Rojo, Juan

    2013-04-15

    Heavy quark structure functions from HERA provide a direct handle on the medium and small-x gluon PDF. In this contribution, we discuss ongoing progress on the implementation of the FONLL General-Mass scheme with running heavy quark masses, and of its benchmarking with the HOPPET and OpenQCDrad codes, and then present the impact of the recently released combined HERA charm production cross sections in the NNPDF 2.3 analysis. We find that the combined charm data contribute to constraining the gluon and quarks at small values of Bjorken-x.

  11. Photon plus Jet Cross Sections at the Tevatron

    E-print Network

    Lars Sonnenschein

    2008-04-03

    Photon plus jet production has been studied by the D0 and CDF experiments in Run II of the Fermilab Tevatron Collider at a center of mass energy of sqrt{s}=1.96 TeV. Measurements of the inclusive photon plus jet, di-photon and photon plus b jet cross section are presented. They are based on integrated luminosities between 0.2 fb^-1 and 1.1 fb^-1. The results are compared to perturbative QCD calculations in various approximations.

  12. Electron Impact K-shell Ionization Cross Sections

    NASA Astrophysics Data System (ADS)

    Patoary, M. A. R.; Alfaz Uddin, M.; Haque, A. K. F.; Shahjahan, M.; Basak, A. K.; Talukder, M. R.; Saha, Bidhan

    2008-10-01

    A new semi-empirical model comprising few important features of the DM [1] model and Bell [2] model is used to evaluate the electron impact K-shell ionization cross sections of 30 atomic targets ranging from H to U (Z=1-92). Details results will be presented at the conference [1] H. Deutsh, K. Becker, T. D. Mark, Int. J. Mass Spect. 177, 47 (1998). [2] K. L. Bell, H. B. Gilbody, J. G. Hughes, A. E. Kingston and F. J. J. Smith, Phys. Chem. Ref. Data 12, 891 (1983).

  13. Cross section measurement on 139La (?,?') below neutron separation energy

    NASA Astrophysics Data System (ADS)

    Makinaga, A.; Rusev, G.; Schwengner, R.; Dönau, F.; Beyer, R.; Bemmerer, D.; Crespo, P.; Erhard, M.; Junghans, A. R.; Klug, J.; Nair, C.; Schilling, K. D.; Wagner, A.

    2010-06-01

    The ?-ray strength function is an important input quantity for the determination of the photoreaction rate and the neutron capture rate for astrophysics as well as for nuclear technologies. Recent studies show that extra ?-ray strength near the neutron separation energy Sn (pygmy resonance) affects the stellar reaction rate strongly. In this work, the photoabsorption cross section for 139La below Sn was measured using bremsstrahlung produced at the electron accelerator ELBE of Eorschungszentrum Dresden-Rossendorf with an electron beam of 11.5 MeV kinetic energy. Experimental result of 139La is presented.

  14. 3He Spin-Dependent Cross Sections and Sum Rules

    SciTech Connect

    Slifer, Karl; Amaryan, Moscov; Amaryan, Moskov; Auerbach, Leonard; Averett, Todd; Berthot, J.; Bertin, Pierre; Bertozzi, William; Black, Tim; Brash, Edward; Brown, D.; Burtin, Etienne; Calarco, John; Cates, Gordon; Chai, Zhengwei; Chen, Jian-Ping; Choi, Seonho; Chudakov, Eugene; Ciofi, Claudio; Cisbani, Evaristo; De Jager, Cornelis; Deur, Alexandre; DiSalvo, R.; Dieterich, Sonja; Djawotho, Pibero; Finn, John; Fissum, Kevin; Fonvieille, Helene; Frullani, Salvatore; Gao, Haiyan; Gao, Juncai; Garibaldi, Franco; Gasparian, Ashot; Gilad, Shalev; Gilman, Ronald; Glamazdin, Oleksandr; Glashausser, Charles; Glockle, W.; Golak, J.; Goldberg, Emma; Gomez, Javier; Gorbenko, Viktor; Hansen, Jens-Ole; Hersman, F.; Holmes, Richard; Huber, Garth; Hughes, Emlyn; Humensky, Thomas; Incerti, Sebastien; Iodice, Mauro; Jensen, S.; Jiang, Xiaodong; Jones, C.; Jones, G.; Jones, Mark; Jutier, Christophe; Kamada, H.; Ketikyan, Armen; Kominis, Ioannis; Korsch, Wolfgang; Kramer, Kevin; Kumar, Krishna; Kumbartzki, Gerfried; Kuss, Michael; Lakuriqi, Enkeleida; Laveissiere, Geraud; LeRose, John; Liang, Meihua; Liyanage, Nilanga; Lolos, George; Malov, Sergey; Marroncle, Jacques; McCormick, Kathy; McKeown, Robert; Meziani, Zein-Eddine; Michaels, Robert; Mitchell, Joseph; Nogga, Andreas; Pace, Emanuele; Papandreou, Zisis; Pavlin, Tina; Petratos, Gerassimos; Pripstein, David; Prout, David; Ransome, Ronald; Roblin, Yves; Rowntree, David; Rvachev, Marat; Sabatie, Franck; Saha, Arunava; Salme, Giovanni; SCOPETTA, S.; Skibinski, R.; Souder, Paul; Saito, Teijiro; Strauch, Steffen; Suleiman, Riad; Takahashi, Kazunori; Todor, Luminita; Tsubota, Hiroaki; Ueno, Hiroaki; Urciuoli, Guido; van der Meer, Rob; Vernin, Pascal; Voskanyan, Hakob; Witala, Henryk; Wojtsekhowski, Bogdan; Xiong, Feng; Xu, Wang; Yang, Jae-Choon; Zhang, Bin; Zolnierczuk, Piotr

    2008-07-01

    We present a measurement of the spin-dependent cross sections for the \\vec{^3He}(\\vec{e},e')X} reaction in the quasielastic and resonance regions at four-momentum transfer 0.1 < Q^2< 0.9 GeV^2. The spin-structure functions have been extracted and used to evaluate the nuclear Burkhardt--Cottingham and extended GDH sum rules for the first time. Impulse approximation and exact three-body Faddeev calculations are also compared to the data in the quasielastic region.

  15. SCALE system cross-section validation for criticality safety analysis

    SciTech Connect

    Hathout, A.M.; Westfall, R.M.; Dodds, H.L. Jr.

    1980-01-01

    The purpose of this study is to test selected data from three cross-section libraries for use in the criticality safety analysis of UO/sub 2/ fuel rod lattices. The libraries, which are distributed with the SCALE system, are used to analyze potential criticality problems which could arise in the industrial fuel cycle for PWR and BWR reactors. Fuel lattice criticality problems could occur in pool storage, dry storage with accidental moderation, shearing and dissolution of irradiated elements, and in fuel transport and storage due to inadequate packing and shipping cask design. The data were tested by using the SCALE system to analyze 25 recently performed critical experiments.

  16. Radar cross section of human cardiopulmonary activity for recumbent subject.

    PubMed

    Kiriazi, John E; Boric-Lubecke, Olga; Lubecke, Victor M

    2009-01-01

    The radar cross section (RCS) corresponding to human cardio-respiratory motion is measured for a subject in two different recumbent positions. Lying face-up (supine), the subject showed an RCS of 0.326 m(2). But when lying face-down (prone), the RCS increased to 2.9 m(2). This is the first reported RCS measurement corresponding to human cardio-respiratory motion. The results obtained in this experiment suggest modeling the upper part of the human body as a half-cylinder where the front body corresponds to the cylindrical surface and the back corresponds to the rectangular one. PMID:19963624

  17. $J/?(?_c) N$ and $?(?_b) N$ cross sections

    E-print Network

    C. W. Xiao; U. -G. Meißner

    2015-08-25

    Inspired by the recent findings of the two $P_c^+$ states in the $J/\\psi p$ mass spectrum at LHCb, we investigate the elastic and inelastic cross sections of the $J/\\psi N$, $\\eta_c N$, $\\Upsilon N$ and $\\eta_b N$ channels within the constraints from heavy quark spin and flavour symmetry. The $\\bar{D}^{(*)} \\Sigma_c^{(*)}$ ($B^{(*)} \\Sigma_b^{(*)}$) bound states predicted in earlier works should be accessible in elastic and/or inelastic processes of the $J/\\psi N$ and/or $\\eta_c N$ ($\\Upsilon N$ and/or $\\eta_b N$) interactions.

  18. Thermal neutron cross section of liquid and solid mesitylene

    NASA Astrophysics Data System (ADS)

    Cantargi, F.; Blostein, J. J.; Torres, L.; Granada, J. R.

    2006-08-01

    Total cross sections of mesitylene at 293 K and at 89 K were measured at the electron LINAC based pulsed neutron source of Centro Atómico Bariloche. Preliminary frequency spectra were proposed for liquid and solid mesitylene at those temperatures combining experimental and synthetic contributions. Scattering law data files were generated with the NJOY nuclear data processing system. Good agreement between experiments and calculations is found, which represents a primary validation of the scattering kernels which are now being used for the design and optimization of a cold moderator employing that material.

  19. Status of multigroup cross-section data for shielding applications

    SciTech Connect

    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.

  20. Cross sections and reaction rates of relevance to aeronomy

    SciTech Connect

    Fox, J.L. )

    1991-01-01

    Experimental and theoretical data relevant to models and measurements of the chemical and thermal structures and luminosity of the thermospheres of the earth and planets published during the last four years are surveyed. Among chemical processes, attention is given to ion-molecule reactions, dissociative recombination of molecular ions, and reactions between neutral species. Both reactions between ground state species and species in excited states are considered, including energy transfer and quenching. Measured and calculated cross sections for interactions of solar radiation with atmospheric species, such as photoabsorption, photoionization, and photodissociation and related processes are surveyed.