Sample records for cross-sectional descriptive correlational

  1. Correlation cross sections along the international border

    SciTech Connect

    Martiniuk, C.D. (Manitoba Energy and Mines, Winnipeg (Canada)); Le Fever, J.A.; Anderson, S.B. (North Dakota Geological Survey, Grand Forks (United States))

    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. Prevalence, Patterns and Correlates of Cigarette Smoking in Male Adolescents in Northern Jordan, and the Influence of Waterpipe Use and Asthma Diagnosis: A Descriptive Cross-Sectional Study

    PubMed Central

    Al-Sheyab, Nihaya; Alomari, Mahmoud A.; Shah, Smita; Gallagher, Patrick; Gallagher, Robyn

    2014-01-01

    Our study investigates the prevalence, patterns and predictors of tobacco smoking among early adolescent males in Northern Jordan and whether asthma diagnosis affects smoking patterns. A descriptive cross sectional design was used. Males in grades 7 and 8 from four randomly selected high schools in the city of Irbid were enrolled. Data on waterpipe (WP) use and cigarette smoking patterns were obtained (n = 815) using a survey in Arabic language. The overall prevalence of ever having smoked a cigarette was 35.6%, with 86.2% of this group smoking currently. Almost half of the sample reported WP use. The most common age in which adolescents started to experiment with cigarettes was 11–12 years old (49.1%), although 10 years was also common (25.3%). Significant predictors of male cigarette smoking were WP use (OR = 4.15, 95% CI = 2.99–5.76), asthma diagnosis (OR = 2.35, 95% CI = 1.46–3.78), grade 8 (OR = 1.52, 95% CI = 1.10–2.11), and having a sibling who smokes (OR = 2.23, 95% CI = 1.53–3.24). However, this cross-sectional study cannot establish causality, thus longitudinal studies are needed. Public health programs and school-based anti-tobacco smoking interventions that target children in early years at high schools are warranted to prevent the uptake of tobacco use among this vulnerable age group. High school students with asthma should be specifically targeted. PMID:25257355

  4. Sequence stratigraphic correlation of well-log cross sections

    SciTech Connect

    Mulholland, J.W.

    1994-07-01

    Correlation of well-log cross sections using the principles of sequence stratigraphy is not as straight forward as it might at first appear. It is a very subjective process, being an interpretation of limited data based on the geologist's knowledge and experience, and consequently, the results can be as varied as the interpreters who do the work. Many decisions are required at each step of the correlation process, and they may be made subjectively (to fit a preconceived understanding of the stratigraphy) or as objectively as possible. Experience has yielded a number of guidelines and [open quotes]rules of thumb[close quotes] that make the process easier and, if not more objective, at least provide a clearer understanding of what assumptions are being made and how they affect the correlation decisions underlying the finished product. This paper provides some of those guidelines. 9 refs., 4 figs.

  5. 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.

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

    SciTech Connect

    Semyonov, A. A.; Druzhaev, A. A., E-mail: andreydruzhaev@gmail.com; Schukin, N. V. [National Research Nuclear University MEPhI (Russian Federation)

    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.

  7. Cross-sectional imaging of primary thoracic sarcomas with histopathologic correlation: a review for the radiologist.

    PubMed

    Dillman, Jonathan R; Pernicano, Perry G; McHugh, Jonathan B; Attili, Anil K; Mourany, Bassem; Pinsky, Renee W; Strouse, Peter J; Kazerooni, Ella A

    2010-01-01

    Numerous forms of primary sarcoma can arise from the heart, pericardium, great vessels, lungs, chest wall, and breasts. Magnetic resonance imaging and computed tomography currently play important roles in determining the extent of primary thoracic sarcoma involvement, potential for resectability, and response to therapy. The purpose of this article is to review the various forms of primary sarcoma that may affect the thorax as well as illustrate pertinent cross-sectional radiologic findings with histopathologic correlation. PMID:19931110

  8. Correlation effects in R-matrix calculations of electron-F2 elastic scattering cross sections.

    PubMed

    Tarana, Michal; Horácek, Jirí

    2007-10-21

    Correlation effects are studied in electron scattering off the fluorine molecule. Fixed-nuclei approximation R-matrix calculations of the elastic collision cross sections are presented for a set of internuclear distances at three levels of correlation. The aim of this work is to study the role of electronic correlation on the properties of the 2Sigmau resonance. The Feshbach-Fano R-matrix method of resonance-background separation is used to study the effect of inclusion of various levels of correlation on the energy and width of the 2Sigmau resonance. Data required for construction of the nonlocal resonance model (construction of a discrete state and its coupling to the continuum) which allows the calculation of inelastic processes such as dissociative electron attachment and vibrational excitation [W. Domcke, Phys. Rep. 208, 97 (1991)] including the correlation are presented. PMID:17949161

  9. A Descriptive Analysis of Oral Health Systematic Reviews Published 1991–2012: Cross Sectional Study

    PubMed Central

    Saltaji, Humam; Cummings, Greta G.; Armijo-Olivo, Susan; Major, Michael P.; Amin, Maryam; Major, Paul W.; Hartling, Lisa; Flores-Mir, Carlos

    2013-01-01

    Objectives To identify all systematic reviews (SRs) published in the domain of oral health research and describe them in terms of their epidemiological and descriptive characteristics. Design Cross sectional, descriptive study. Methods An electronic search of seven databases was performed from inception through May 2012; bibliographies of relevant publications were also reviewed. Studies were considered for inclusion if they were oral health SRs defined as therapeutic or non-therapeutic investigations that studied a topic or an intervention related to dental, oral or craniofacial diseases/disorders. Data were extracted from all the SRs based on a number of epidemiological and descriptive characteristics. Data were analysed descriptively for all the SRs, within each of the nine dental specialities, and for Cochrane and non-Cochrane SRs separately. Results 1,188 oral health (126 Cochrane and 1062 non-Cochrane) SRs published from 1991 through May 2012 were identified, encompassing the nine dental specialties. Over half (n?=?676; 56.9%) of the SRs were published in specialty oral health journals, with almost all (n?=?1,178; 99.2%) of the SRs published in English and almost none of the non-Cochrane SRs (n?=?11; 0.9%) consisting of updates of previously published SRs. 75.3% of the SRs were categorized as therapeutic, with 64.5% examining non-drug interventions, while approximately half (n?=?150/294; 51%) of the non-therapeutic SRs were classified as epidemiological SRs. The SRs included a median of 15 studies, with a meta-analysis conducted in 43.6%, in which a median of 9 studies/1 randomized trial were included in the largest meta-analysis conducted. Funding was received for 25.1% of the SRs, including nearly three-quarters (n?=?96; 76.2%) of the Cochrane SRs. Conclusion Epidemiological and descriptive characteristics of the 1,188 oral health SRs varied across the nine dental specialties and by SR category (Cochrane vs. non-Cochrane). There is a clear need for more updates of SRs in all the dental specialties. PMID:24098657

  10. Electron-atom bremsstrahlung: Double-differential cross section and polarization correlations

    SciTech Connect

    Yerokhin, Vladimir A. [Institute of Physics, University of Heidelberg, Philosophenweg 12, D-69120 Heidelberg (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstrasse 1, D-64291 Darmstadt (Germany); Center for Advanced Studies, St. Petersburg State Polytechnical University, Polytekhnicheskaya 29, St. Petersburg 195251 (Russian Federation); Surzhykov, Andrey [Institute of Physics, University of Heidelberg, Philosophenweg 12, D-69120 Heidelberg (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung, Planckstrasse 1, D-64291 Darmstadt (Germany)

    2010-12-15

    The leading-order electron-atom bremsstrahlung is investigated within the rigorous relativistic approach based on the partial-wave representation of the Dirac wave functions in the external atomic field. Approximating the atomic target by an effective local potential, we calculate the double-differential cross section and the polarization correlations in a wide range of the impact energies. Connection between the bremsstrahlung at the hard-photon end point of the spectrum and the continuum-threshold limit of the radiative recombination is studied. A detailed analysis of the screening effect and the energy dependence of the polarization correlations is presented, with the main focus on the high-impact-energy region.

  11. Physical activity and its correlates in children: a cross-sectional study (the GINIplus & LISAplus studies)

    PubMed Central

    2013-01-01

    Background Physical inactivity among children is an increasing problem that adversely affects children’s health. A better understanding of factors which affect physical activity (PA) will help create effective interventions aimed at raising the activity levels of children. This cross-sectional study examined the associations of PA with individual (biological, social, behavioral, psychological) and environmental (East vs. West Germany, rural vs. urban regions) characteristics in children. Methods Information on PA and potential correlates was collected from 1843 girls and 1997 boys using questionnaires during the 10-year follow-up of two prospective birth cohort studies (GINIplus and LISAplus). Study regions represent urban and rural sites as well as East and West of Germany. Logistic regression modeling was applied to examine cross-sectional associations between individual as well as environmental factors and PA levels. Results Five of fourteen variables were significantly associated with PA. Among children aged 10, girls tended to be less active than boys, especially with respect to vigorous PA (OR?=?0.72 for summer). Children who were not a member of a sports club showed a substantially reduced amount of PA in winter (OR?=?0.15). Rural environments promote moderate PA, particularly in winter (OR?=?1.88), whereas an increased time outdoors primarily promotes moderate PA in summer (OR?=?12.41). Children with abnormal emotional symptoms exhibited reduced physical activity, particularly in winter (OR?=?0.60). BMI, puberty, parental BMI, parental education, household income, siblings, TV/PC consumption, and method of arriving school, were not associated with PA. Conclusions When considering correlates of PA from several domains simultaneously, only few factors (sex, sports club membership, physical environment, time outdoors, and emotional symptoms) appear to be relevant. Although the causality needs to be ascertained in longitudinal studies, variables which cannot be modified should be used to identify risk groups while modifiable variables, such as sports club activities, may be addressed in intervention programs. PMID:23587274

  12. A cross-sectional description of social capital in an international sample of persons living with HIV/AIDS (PLWH)

    PubMed Central

    2012-01-01

    Background Social capital refers to the resources linked to having a strong social network. This concept plays into health outcomes among People Living with HIV/AIDS because, globally, this is a highly marginalized population. Case studies show that modifying social capital can lead to improvements in HIV transmission and management; however, there remains a lack of description or definition of social capital in international settings. The purpose of our paper was to describe the degree of social capital in an international sample of adults living with HIV/AIDS. Methods We recruited PLWH at 16 sites from five countries including Canada, China, Namibia, Thailand, and the United States. Participants (n = 1,963) completed a cross-sectional survey and data were collected between August, 2009 and December, 2010. Data analyses included descriptive statistics, factor analysis, and correlational analysis. Results Participant's mean age was 45.2 years, most (69%) identified as male, African American/Black (39.9%), and unemployed (69.5%). Total mean social capital was 2.68 points, a higher than average total social capital score. Moderate correlations were observed between self-reported physical (r = 0.25) and psychological condition (r = 0.36), social support (r = 0.31), and total social capital. No relationships between mental health factors, including substance use, and social capital were detected. Conclusions This is the first report to describe levels of total social capital in an international sample of PLWH and to describe its relationship to self-reported health in this population. PMID:22414342

  13. Correlates of unsupervised bathing of infants: a cross-sectional study.

    PubMed

    van Beelen, Mirjam E J; van Beeck, Eduard F; den Hertog, Paul; Beirens, Tinneke M J; Raat, Hein

    2013-03-01

    Drowning represents the third leading cause of fatal unintentional injury in infants (0-1 years). The aim of this study is to investigate correlates of unsupervised bathing. This cross-sectional study included 1,410 parents with an infant. Parents completed a questionnaire regarding supervision during bathing, socio-demographic factors, and Protection Motivation Theory-constructs. To determine correlates of parents who leave their infant unsupervised, logistic regression analyses were performed. Of the parents, 6.2% left their child unsupervised in the bathtub. Parents with older children (OR 1.24; 95%CI 1.00-1.54) were more likely to leave their child unsupervised in the bathtub. First-time parents (OR 0.59; 95%CI 0.36-0.97) and non-Western migrant fathers (OR 0.18; 95%CI 0.05-0.63) were less likely to leave their child unsupervised in the bathtub. Furthermore, parents who perceived higher self-efficacy (OR 0.57; 95%CI 0.47-0.69), higher response efficacy (OR 0.34; 95%CI 0.24-0.48), and higher severity (OR 0.74; 95%CI 0.58-0.93) were less likely to leave their child unsupervised. Since young children are at great risk of drowning if supervision is absent, effective strategies for drowning prevention should be developed and evaluated. In the meantime, health care professionals should inform parents with regard to the importance of supervision during bathing. PMID:23459215

  14. Target correlation effects on neutron-nucleus total, absorption, and abrasion cross sections

    NASA Technical Reports Server (NTRS)

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

    1991-01-01

    Second order optical model solutions to the elastic scattering amplitude were used to evaluate total, absorption, and abrasion cross sections for neutron nucleus scattering. Improved agreement with experimental data for total and absorption cross sections is found when compared with first order (coherent approximation) solutions, especially below several hundred MeV. At higher energies, the first and second order solutions are similar. There are also large differences in abrasion cross section calculations; these differences indicate a crucial role for cluster knockout in the abrasion step.

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

    SciTech Connect

    Vititoe, D.L. [Arizona Univ., Tucson, AZ (United States). Dept. of Physics; 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. 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

  17. D0 results on three-jet production, multijet cross-section ratios, and minimum bias angular correlations

    SciTech Connect

    Sawyer, Lee; /Louisiana Tech. U.

    2010-01-01

    We report the measurement of the cross-section for three-jet production and the ratio of inclusive three-jet to two-jet cross-sections, as well as a study of angular correlations in minimum bias events, based on data taken with the D0 experiment at the Fermilab Tevatron proton-antiproton collider. The differential inclusive three-jet cross section as a function of the invariant three-jetmass (M{sub 3jet}) is measured in p{bar p} collisions at {radical}s = 1.96 TeV using a data set corresponding to an integrated luminosity of 0.7 fb{sup -1}. The measurement is performed in three rapidity regions (|y| < 0.8, |y| < 1.6 and |y| < 2.4) and in three regions of the third (ordered in p{sub T}) jet transverse momenta (p{sub T3} > 40 GeV, p{sub T3} > 70 GeV, p{sub T3} > 100 GeV) for events with leading jet transverse momentum larger than 150 GeV and well separated jets. NLO QCD calculations are found to be in a reasonable agreement with the measured cross sections. Based on the same data set, we present the first measurement of ratios of multi-jet cross sections in p{bar p} collisions at {radical}s = 1.96 TeV at the Fermilab Tevatron Collider. The ratio of inclusive trijet and dijet cross sections, R{sub 3/2}, has been measured as a function of the transverse jet momenta. The data are compared to QCD model predictions in different approximations. Finally, we present a new way to describe minimum bias events based on angular distributions in {approx}5 million minimum bias p{bar p} collisions collected between April 2002 and February 2006 with the D0 detector. We demonstrate that the distribution of {Delta}{phi} in the detector transverse plane between the leading track and all other tracks is a robust observable that can be used for tuning of multiple color interaction models. Pseudorapidity correlations of the {Delta}{phi} distributions are also studied.

  18. Description of nuclear structure and cross sections for nucleon-nucleus scattering on the basis of effective Skyrme forces

    SciTech Connect

    Kuprikov, V. I.; Pilipenko, V. V.; Soznik, A. P.; Tarasov, V. N.; Shlyakhov, N. A. [Kharkiv Institute for Physics and Technology (Ukraine)

    2009-06-15

    The possibility of constructing such new versions of effective nucleon-nucleon forces that would make it possible to describe simultaneously the cross sections for nucleon-nucleus scattering and quantities characterizing nuclear matter and the structure of finite even-even nuclei is investigated on the basis of a microscopic nucleon-nucleus optical potential that is calculated by using effective Skyrme interaction. A procedure for optimizing the parameters of Skyrme forces by employing fits to specific angular distributions for neutron-nucleus scattering and by simultaneously testing the features of nuclear matter, the binding energy of the target nucleus, and its proton root-mean-square radius is proposed. A number of versions of modified Skyrme forces that ensure a reasonable description of both nucleon-nucleus scattering and the properties of nuclear structure are found on the basis of this procedure.

  19. 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

  20. A descriptive cross-sectional international study to explore current practices in the assessment, prevention and treatment of skin tears.

    PubMed

    LeBlanc, Kimberly; Baranoski, Sharon; Holloway, Samantha; Langemo, Diane; Regan, Mary

    2014-08-01

    This study presents the results of a descriptive, cross-sectional, online international survey in order to explore current practices in the assessment, prediction, prevention and treatment of skin tears (STs). A total of 1127 health care providers (HCP) from 16 countries completed the survey. The majority of the respondents (69·6%, n?=?695) reported problems with the current methods for the assessment and documentation of STs with an overwhelming majority (89·5%, n?=?891) favouring the development of a simplified method of assessment. Respondents ranked equipment injury during patient transfer and falls as the main causes of STs. The majority of the samples indicated that they used non-adhesive dressings (35·89%, n?=?322) to treat a ST, with the use of protective clothing being the most common method of prevention. The results of this study led to the establishment of a consensus document, classification system and a tool kit for use by practitioners. The authors believe that this survey was an important first step in raising the global awareness of STs and to stimulate discussion and research of these complex acute wounds. PMID:24443829

  1. Cross Section Flyer

    NSDL National Science Digital Library

    2011-03-16

    In this activity, students use slider bars to move a cross section of a cone, cylinder, prism, or pyramid. This activity allows students to explore conic sections and the 3-dimensional shapes from which they are derived. This activity includes supplemental materials, including background information about the topics covered, a description of how to use the application, and exploration questions for use with the java applet.

  2. Indoor household residual spraying program performance in Matabeleland South province, Zimbabwe: 2011 to 2012; a descriptive cross-sectional study

    PubMed Central

    Chimberengwa, Pugie Tawanda; Masuka, Nyasha; Gombe, Notion Tafara; Tshimanga, Mufuta; Takundwa, Lucia; Bangure, Donewell

    2015-01-01

    Introduction Matabeleland South launched the malaria pre-elimination campaign in 2012 but provincial spraying coverage has failed to attain 95% target, with some districts still encountering malaria outbreaks. A study was conducted to evaluate program performance against achieving malaria pre-elimination. Methods A descriptive cross sectional study was done in 5 districts carrying out IRS using the logical framework involving inputs, process, outputs and outcome evaluation. Health workers recruited into the study included direct program implementers, district and provincial program managers. An interviewer administered questionnaire, checklists, key informant interviewer guide and desk review of records were used to collect data. Results We enrolled 37 primary respondents and 5 key informants. Pre-elimination, Epidemic Preparedness and Response plans were absent in all districts. Shortages of inputs were reported by 97% of respondents, with districts receiving 80% of requested budget. Insecticides were procured centrally at national level. Spraying started late and districts failed to spray all targeted households by end of December. The province is using makeshift camps with inappropriate evaporation ponds where liquid DDT waste is not safely accounted for. The provincial IHRS coverage for 2011 was 84%. Challenges cited included; food shortages for spraymen, late delivery of inputs and poor state of IHRS equipment. Conclusion The province has failed to achieve Malaria pre-elimination IRS coverage targets for 2011/12 season. Financial and logistical challenges led to delays in supply of program inputs, recruitment and training of sprayers. The Province should establish camping infrastructure with standard evaporation ponds to minimise contamination of the environment. PMID:26015847

  3. 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

  4. Correlation between arch form and facial form: A cross sectional study

    PubMed Central

    Nayar, Sanjna; Aruna; Santhosh; Manzoor, Wasim

    2015-01-01

    Arch form is a key determinant in teeth position. Teeth selection and placement must be based on the functional and esthetic needs of the patient. Keeping in mind, the biomechanics involved with the prosthesis. The aim of the study was to evaluate the correlation between arch form and facial form. About 40 individuals in the age group of 20-25 years were involved in the study. The arch form and facial form were analyzed statistically to check for any correlation. It was found that, 63.63% of leptoprosophic individuals had squarish arch form while, 54.6% of mesoprosophic faces had ovoid arch form. PMID:26015761

  5. The recent absolute total np and pp cross section determinations: quality of data description and prediction of experimental observables

    SciTech Connect

    Laptev, Alexander B [Los Alamos National Laboratory; Haight, Robert C [Los Alamos National Laboratory; Arndt, Richard A [GWU; Briscoe, William J [GWU; Paris, Mark W [GWU; Strakovsky, Igor I [GWU; Workman, Ron L [GWU

    2010-01-01

    The absolute total cross sections for np and pp scattering below 1000 MeV 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-3.3 data files, and the Nijmegen PWA. Systematic deviations from the ENDF/B-VII.0 and JENDL-3.3 evaluations are found to exist in the low-energy region. Comparison of the np evaluation with the result of most recent np total and differential cross section measurements will be discussed. Results of those measurements were not used in the evaluation database. A comparison was done to check a quality of evaluation and its capabilities to predict experimental observables. Excellent agreement was found between the new experimental data and our PWA predictions.

  6. Patterns and correlates of physical activity: a cross-sectional study in urban Chinese women

    Microsoft Academic Search

    Adriana L Jurj; Wanqing Wen; Yu-Tang Gao; Charles E Matthews; Gong Yang; Hong-Lan Li; Wei Zheng; Xiao-Ou Shu

    2007-01-01

    BACKGROUND: Inactivity is a modifiable risk factor for many diseases. Rapid economic development in China has been associated with changes in lifestyle, including physical activity. The purpose of this study was to investigate the patterns and correlates of physical activity in middle-aged and elderly women from urban Shanghai. METHODS: Study population consisted of 74,942 Chinese women, 40–70 years of age,

  7. 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,

  8. Correlation of serum liver fibrosis markers with severity of liver dysfunction in liver cirrhosis: a retrospective cross-sectional study

    PubMed Central

    Zhu, Cuihong; Qi, Xingshun; Li, Hongyu; Peng, Ying; Dai, Junna; Chen, Jiang; Xia, Chunlian; Hou, Yue; Zhang, Wenwen; Guo, Xiaozhong

    2015-01-01

    Hyaluronic acid (HA), laminin (LN), amino-terminal pro-peptide of type III pro-collagen (PIIINP), and collagen IV (CIV) are four major serum markers of liver fibrosis. This retrospective cross-sectional study aimed to evaluate the correlations of the four serum markers with the severity of liver dysfunction in cirrhotic patients. Between January 2013 and June 2014, a total of 228 patients with a clinical diagnosis with liver cirrhosis and without malignancy underwent the tests of HA, LN, PIIINP, and CIV levels. Laboratory data were collected. Child-Pugh and model for the end-stage of liver diseases (MELD) scores were calculated. Of them, 32%, 40%, and 18% had Child-Pugh class A, B, and C, respectively. MELD score was 7.58±0.50. HA (coefficient r: 0.1612, P=0.0203), LN (coefficient r: 0.2445, P=0.0004), and CIV (coefficient r: 0.2361, P=0.0006) levels significantly correlated with Child-Pugh score, but not PIIINP level. Additionally, LN (coefficient r: 0.2588, P=0.0002) and CIV (coefficient r: 0.1795, P=0.0108) levels significantly correlated with MELD score, but not HA or PIIINP level. In conclusions, HA, LN, and CIV levels might be positively associated with the severity of liver dysfunction in cirrhotic patients. However, given a relatively weak correlation between them, our findings should be cautiously interpreted and further validated.

  9. Morning melatonin serum values do not correlate with disease activity in rheumatoid arthritis: a cross-sectional study.

    PubMed

    Afkhamizadeh, Mozhgan; Sahebari, Maryam; Seyyed-Hoseini, Seyyed-Reza

    2014-08-01

    Rheumatoid arthritis (RA), the most prevalent autoimmune arthritis worldwide, usually presents with a circannual manner and, meanwhile, follows a circadian rhythm for symptoms like morning stiffness. Therefore, association between RA and some hormones such as melatonin (MLT) and vitamin D, whose serum values are related to body circadian rhythms or seasonal variations, has become more noticeable recently. Since some studies proposed that RA patients show altered MLT circadian rhythms, especially in concordance with symptoms, in this research, we present the correlation between MLT serum values and RA disease activity score (DAS28ESR). The current cross-sectional study was carried out on 80 volunteers (60 patients and 20 healthy controls). Fifty percent of the participants in each group were sampled in cold, and the same percentage were sampled in warm seasons at 8 a.m. Disease activity was estimated utilizing DAS28ESR. Patients with possible known confounders of MLT secretion were excluded. A commercial MLT ELISA kit was employed to measure MLT. Statistical analysis was conducted by SPSS-11 software. This study outlined higher serum values of MLT in RA patients compared with controls (P = 0.006, z = -2.73). However, MLT did not correlate with DAS in patients (P = 0.45, r = -0.09). GLM analysis demonstrated that DAS28ESR, age, disease duration, medications, gender, and season of sampling had no influence on serum MLT. However, newly diagnosed RA patients presented higher MLT values than established ones (P = 0.03, t = -2.2). A cutoff point value of 23 pg/mL (63.3 % sensitivity and 90 % specificity) for MLT was computed between patients and controls. This study denoted that morning MLT serum values are higher in RA patients than in healthy volunteers. However, MLT and RA disease activity or other disease characteristics do not correlate. MLT serum values were higher in newly diagnosed RA patients than established ones. PMID:24487422

  10. Photoionization of Xe inside C{sub 60}: Atom-fullerene hybridization, giant cross-section enhancement, and correlation confinement resonances

    SciTech Connect

    Madjet, Mohamed E.; Renger, Thomas; Hopper, Dale E.; McCune, Matthew A.; Chakraborty, Himadri S.; Rost, Jan-M.; Manson, Steven T. [Institute of Chemistry and Biochemistry, Free University, Fabeckstrasse 36a, D-14195 Berlin (Germany); Center for Innovation and Entrepreneurship, Department of Chemistry and Physics, Northwest Missouri State University, Maryville, Missouri 64468 (United States); Max-Planck-Institut fuer Physik Komplexer Systeme, Noethnitzer Strasse 38, D-01187 Dresden (Germany); Department Physics and Astronomy, Georgia State University, Atlanta, Georgia 30303 (United States)

    2010-01-15

    A theoretical study of the subshell photoionization of the Xe atom endohedrally confined in C{sub 60} is presented. Powerful hybridization of the Xe 5s state with the bottom edge of C{sub 60} pi band is found that induces strong structures in the 5s ionization, causing the cross section to differ significantly from earlier results that omit this hybridization. The hybridization also affects the angular distribution asymmetry parameter of Xe 5p ionization near the Cooper minimum. The 5p cross section, on the other hand, is greatly enhanced by borrowing considerable oscillator strength from the C{sub 60} giant plasmon resonance via the atom-fullerene dynamical interchannel coupling. Beyond the C{sub 60} plasmon energy range the atomic subshell cross sections display confinement-induced oscillations in which, over the large 4d shape resonance region, the dominant 4d oscillations induce their 'clones' in all degenerate weaker channels known as correlation confinement resonances.

  11. Prevalence and Correlates of Diabetic Peripheral Neuropathy in a Saudi Arabic Population: A Cross-Sectional Study

    PubMed Central

    Wang, Dong D.; Bakhotmah, Balkees A.; Hu, Frank B.; Alzahrani, Hasan Ali

    2014-01-01

    The purpose of this cross-sectional study was to investigate the prevalence and correlates of diabetic peripheral neuropathy (DPN) in a Saudi population. The study population consisted of 552 diabetic participants with an average age of 53.4 years. Among this population, 62.7% were male and 94.9% had type 2 diabetes. The average body mass index was 31.1 kg/m2. DPN was diagnosed based on a combination of reduced vibration perception measured by neurothesiometer and/or reduced light touch perception evaluated by the 10-g Semmes-Weinstein monofilament, as well as neurological symptoms. Information on socio-demographic variables, smoking status, duration of diabetes, and medications was obtained through interviews by physicians. Body weight, height, waist circumference, blood pressure and clinical markers were assessed following standard procedures. The prevalence of DPN in this population was 19.9% (95% CI, 16.7%-23.5%). In the multivariable analyses, longer duration of diabetes [odds ratio (OR) for every 5-year increase, 2.49, 95% CI, 1.75-3.53], abdominal obesity (OR, 2.53, 95% CI, 1.41-4.55), and higher levels of fasting blood glucose (OR for every 1 mmol/L increase, 1.05, 95% CI, 0.99-1.12), creatinine (OR for every 10 µmol/L increase, 1.07, 95% CI, 0.99-1.14) and white blood cell count (OR for every 106/L increase, 1.08, 95% CI, 1.01-1.16) were associated with higher odds of DPN, while oral hypoglycemic medication use was associated with a lower odds of DPN (OR, 0.47, 95% CI, 0.26-0.85). In this large Saudi population, several correlates for DPN, in addition to glycemic control and diabetes duration, were identified, including abdominal obesity, creatinine and white blood cell count. PMID:25184511

  12. Prevalence and correlates of diabetic peripheral neuropathy in a Saudi Arabic population: a cross-sectional study.

    PubMed

    Wang, Dong D; Bakhotmah, Balkees A; Hu, Frank B; Alzahrani, Hasan Ali

    2014-01-01

    The purpose of this cross-sectional study was to investigate the prevalence and correlates of diabetic peripheral neuropathy (DPN) in a Saudi population. The study population consisted of 552 diabetic participants with an average age of 53.4 years. Among this population, 62.7% were male and 94.9% had type 2 diabetes. The average body mass index was 31.1 kg/m2. DPN was diagnosed based on a combination of reduced vibration perception measured by neurothesiometer and/or reduced light touch perception evaluated by the 10-g Semmes-Weinstein monofilament, as well as neurological symptoms. Information on socio-demographic variables, smoking status, duration of diabetes, and medications was obtained through interviews by physicians. Body weight, height, waist circumference, blood pressure and clinical markers were assessed following standard procedures. The prevalence of DPN in this population was 19.9% (95% CI, 16.7%-23.5%). In the multivariable analyses, longer duration of diabetes [odds ratio (OR) for every 5-year increase, 2.49, 95% CI, 1.75-3.53], abdominal obesity (OR, 2.53, 95% CI, 1.41-4.55), and higher levels of fasting blood glucose (OR for every 1 mmol/L increase, 1.05, 95% CI, 0.99-1.12), creatinine (OR for every 10 µmol/L increase, 1.07, 95% CI, 0.99-1.14) and white blood cell count (OR for every 106/L increase, 1.08, 95% CI, 1.01-1.16) were associated with higher odds of DPN, while oral hypoglycemic medication use was associated with a lower odds of DPN (OR, 0.47, 95% CI, 0.26-0.85). In this large Saudi population, several correlates for DPN, in addition to glycemic control and diabetes duration, were identified, including abdominal obesity, creatinine and white blood cell count. PMID:25184511

  13. NEUTRON CROSS SECTIONS

    Microsoft Academic Search

    Donald J. Hughes; R. B. Schwartz

    1958-01-01

    The material in the first edition of BNL-325 and its addendum, the ; supplement, and new data received up to May, 1958 are included. Thermal cross ; sections, resonance parameters, and cross section curves are given. (M.H.R.)

  14. 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

  15. Correlates of sexual behaviors with health status and health perception in Chinese adolescents: a cross-sectional survey in schools.

    PubMed

    Wong, William C W; Lee, Albert; Tsang, Kwong Ka

    2004-08-01

    Sexual intercourse remains taboo among adolescents in a Chinese society such as Hong Kong. It is not openly discussed and little research has been done on its impact on health, although it carries serious risks of contracting sexually transmitted diseases (STDs)/HIV. In 1999, a cross-sectional, self-report survey on youth risk behaviors was carried out on 8382 students 15-18 years of age from 48 schools in Hong Kong. Three hundred seventy-seven (4.69%) reported that they had had sexual intercourse. Among them, forced sex (16.94%) was common, most often happening to boys (52.38%). They were more likely to have consulted doctors in the last month (odds ration [OR] 1.41 in boys 95% confidence interval [CI] 1.03, 1.94; OR 2.46 in girls 95% CI 1.81, 3.30) and 6 months (OR 1.33 in boys 95% CI 0.98, 1.78; OR 2.66 in girls 95% CI 1.80, 3.91). They also perceived poorer and deteriorating health. The sexually active female students were 6.70 times (95% CI 4.65, 9.66) more likely to attempt suicide than the other group and were more likely to take sick leaves (OR 3.56 in girls 95% CI 2.35, 5.41). Parental education and occupation, place of birth, and type of housing did not correlate in the initiation of sexual intercourse. The sexually experienced group reported worse physical and psychological health as well as health perception. Some of the characteristics and patterns identified in our study were quite different from the findings in the West but further studies are required to determine the reason for this. PMID:15321018

  16. The spectrum and solutions of the generalized BFKL equation for total cross section

    Microsoft Academic Search

    N. N. Nikolaeva; B. G. Zakharova; L. D. Landau

    The colour dipole cross section is the principal quantity in the lightcone s-channel description of the diffractive scattering. Recently we have shown that the dipole cross section satisfies the generalized BFKL equation. In this paper we discuss properties and solutions of our generalized BFKL equation with allowance for the finite gluon correlation radius Rc. The latter is intro- duced in

  17. Failure of hospital employees to comply with smoke-free policy is associated with nicotine dependence and motives for smoking: a descriptive cross-sectional study at a teaching hospital in the United Kingdom

    E-print Network

    Parks, Tom; Wilson, Clare V R; Turner, Kenrick; Chin, Joel W E

    2009-07-15

    the smoking behaviours of compliant and non-compliant smokers, specifically that non-compliance would be associated with nicotine dependence and different reasons for smoking. Methods We conducted a questionnaire-based, descriptive, cross-sectional study...

  18. Effects of instructional strategies using cross sections on the recognition of anatomical structures in correlated CT and MR images

    NSDL National Science Digital Library

    Dr. Mohammed K Khalil (Tuskegee University College of Veterinary Medicine Biomedical Sciences)

    2008-03-01

    This article describes a research study with novice medical students and biology students exploring the cognitive load of anatomical images using three methods; cross sectional images, transparent highlighting of anatomical structures and a combination of the two. Outcomes on the impact of these strategies on cognitive load and learning are discussed.

  19. Serological cross-sectional studies on salmonella incidence in eight European countries: no correlation with incidence of reported cases

    PubMed Central

    2012-01-01

    Background Published incidence rates of human salmonella infections are mostly based on numbers of stool culture-confirmed cases reported to public health surveillance. These cases constitute only a small fraction of all cases occurring in the community. The extent of underascertainment is influenced by health care seeking behaviour and sensitivity of surveillance systems, so that reported incidence rates from different countries are not comparable. We performed serological cross-sectional studies to compare infection risks in eight European countries independent of underascertainment. Methods A total of 6,393 sera from adults in Denmark, Finland, France, Italy, Poland, Romania, Sweden, and The Netherlands were analysed, mostly from existing serum banks collected in the years 2003 to 2008. Immunoglobulin A (IgA), IgM, and IgG against salmonella lipopolysaccharides were measured by in-house mixed ELISA. We converted antibody concentrations to estimates of infection incidence (‘sero-incidence’) using a Bayesian backcalculation model, based on previously studied antibody decay profiles in persons with culture-confirmed salmonella infections. We compared sero-incidence with incidence of cases reported through routine public health surveillance and with published incidence estimates derived from infection risks in Swedish travellers to those countries. Results Sero-incidence of salmonella infections ranged from 56 (95% credible interval 8–151) infections per 1,000 person-years in Finland to 547 (343–813) in Poland. Depending on country, sero-incidence was approximately 100 to 2,000 times higher than incidence of culture-confirmed cases reported through routine surveillance, with a trend for an inverse correlation. Sero-incidence was significantly correlated with incidence estimated from infection risks in Swedish travellers. Conclusions Sero-incidence estimation is a new method to estimate and compare the incidence of salmonella infections in human populations independent of surveillance artefacts. Our results confirm that comparison of reported incidence between countries can be grossly misleading, even within the European Union. Because sero-incidence includes asymptomatic infections, it is not a direct measure of burden of illness. But, pending further validation of this novel method, it may be a promising and cost-effective way to assess infection risks and to evaluate the effectiveness of salmonella control programmes across countries or over time. PMID:22799896

  20. Photoionization cross sections involving an explicitly correlated initial state: Combination of multiconfigurational linear response and the stieltjes—tchebycheff moment theory

    NASA Astrophysics Data System (ADS)

    Swanstrøm, Peter; Golab, Joseph T.; Yeager, Danny L.; Nichols, Jeffrey A.

    1986-12-01

    We have performed outer valence photoionization cross section calculations for N 2 and O 2. To do this we have combined several linear response techniques, in particular time-dependent Hartree—Fock (TDHF), multiconfigurational time-dependent Hartree—Fock (MC TDHF), and a modification of MC TDHF (MMC TDHF) with Stieltjes—Tchebycheff moment theory (STMT). To our knowledge, these MC TDHF and MMC TDHF calculations are the first which combine explicitly correlated Green function approaches with STMT. Since, in addition, these calculations are fully coupled, we expect the MC TDHF and in particular the MMC TDHF—STMT results to be highly reliable. For both N 2 and O 2 our MC TDHF—STMT and MMC TDHF—STMT results are in overall agreement with previous static exchange STMT results; however, there are a few significant differences and differences in detail in the partial and total photoionization cross sections. In particular, for example, for N 2 we note that the MMC TDHF—STMT does not give a "hump" resonance in the cross section for the (1? u-1)A 2? u ionic state. In O 2 we note that the (3? g-1) cross section obtained using MMC TDHF—STMT is substantially lower than the static exchange results.

  1. 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?

  2. 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.

  3. Description of light ion production cross sections and fluxes on the Mars surface using the QMSFRG model.

    PubMed

    Cucinotta, Francis A; Kim, Myung-Hee; Schneider, Susana I; Hassler, Donald M

    2007-06-01

    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 near 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 the RAD experiment. Finally, we consider sensitivity assessments of the impact of the Martian atmospheric composition on particle fluxes at the surface. PMID:17342547

  4. The b{bar b} production cross section and correlations in p{bar p} collisions at {radical}s = 1.8 TeV

    SciTech Connect

    Gomez, B.; Hoeneisen, B.; Negret, J.P. [Universidad de los Andes, Begota (Colombia)] [and others

    1996-08-01

    The authors present measurements of the b{bar b} production cross section and angular correlations between the b and {bar b}-quarks in p{bar p} collisions using the D0 detector at the Fermilab Tevatron operating at {radical}s = 1.8 TeV. The b-quark production cross section for {vert_bar}y{sup b}{vert_bar} < 1.0 and {rho}{sub {tau}}{sup b} > 8 GeV/c is extracted and found to be consistent with next-to-leading order QCD predictions. In addition, the angular correlations between the b and {bar b}-quarks are found to agree in shape with next-to-leading order QCD predictions.

  5. Correlation of irradiation creep data obtained in fast and thermal neutron spectra with displacement cross-sections

    NASA Astrophysics Data System (ADS)

    Foster, J. P.; Boltax, A.

    1980-04-01

    Irradiation creep data are available for 20% cold-worked M316 stainless steel, 20% cold-worked FV548 stainless steel, solution-annealed 304 stainless steel and aged Nimonic PE16 for the same heats of material and state of stress tested in thermal and fast neutron reactors. The transient and steady state irradiation creep coefficients were calculated using spectrum-averaged displacement cross-section dose units (i.e. displacements per atom). The transient irradiation creep coefficients appear to be subject to considerable scatter. The steady state irradiation creep coefficients were found to be a consistent factor of 2.5 larger in thermal than fast reactors. These results are in excellent agreement with the fast reactor dose rate dependence of the steady state irradiation creep rate observed by Lewthwaite and Mosedale. However, the dose rate effect-directly depends on the displacement cross-section, which is a calculated dependent parameter. The available information suggests that the displacement cross-section function uncertainty is the major effect responsible for the 2.5 factor in irradiation creep coefficients.

  6. Geologic Cross Sections

    NSDL National Science Digital Library

    Sharon Browning

    For this project, students must select a several hundred kilometer long section of Earth's surface, ideally crossing one or more major plate boundaries and research all major tectonic events to construct a cross section. Students should also take into account other factors like age of the ocean floor, average elevation and gravity anomalies across their area. The purpose is to demonstrate the geologic/tectonic history of their cross section and present it in a clear, concise summary.

  7. Direct reaction effects on compound cross sections

    Microsoft Academic Search

    P. A. Moldauer

    1975-01-01

    Two effects of a direct reaction on compound processes are discussed: the enhancement of the average compound cross section that competes with the direct process and the cross correlations in the fluctuations of cross sections involving the directly coupled channels. For the case of two directly coupled channels it is shown that both effects are maximized at the causality limit

  8. Direct reaction effects on compound cross sections

    Microsoft Academic Search

    P. Moldauer

    1975-01-01

    Two effects of a direct reaction on compound processes are discussed: ; the enhancement of the average compound cross section that competes with the ; direct process and the cross correlations in the fluctuations of cross sections ; involving the directly coupled channels. For the case of two directly coupled ; channels it is shown that both effects are maximized

  9. 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?

  10. NEUTRON ACTIVATION CROSS SECTIONS

    Microsoft Academic Search

    J. A. Miskel; K. V. Marsh; M. Lindner; R. J. Nagle

    1959-01-01

    The (n, ) activation cross sections of several nuclides were measured ; as a function of neutron energy. The neutron energy range covered was from 31 ; kev to 6 Mev. The nuclides studied were Hf¹⁸°, Ta¹⁸¹,W¹⁸⁶,Au\\/; sup 197\\/, and Th\\/sup 232. (auth)

  11. Correlations and uctuations of matrix elements and cross sections Bruno Eckhardt, Imre Varga and P eter Pollner a

    E-print Network

    Pollner, Péter

    with respect to the width. The #12;rst term is familiar from the analysis of Ericsson uc- tuations in nuclear 2. Matrix element correlations within ran- dom matrix theory The quantity we focus on is the density

  12. Investigating the Correlates and Predictors of Affective and Continuance Organizational Commitment: A Cross sectional Survey of Malaysian Academic Librarians

    Microsoft Academic Search

    Noor Hasrul; Nizan Mohammd Noor

    This study attempts to identify the correlates and predictors of affective and continuance organizational commitment. Meyer & Allen's (1997) conceptualization and operationalization of organizational commitment has been adopted for this study. This study was carried out to determine whether work related variables such as job satisfaction, job involvement, job autonomy, job performance feedback, role conflict and role clarity would have

  13. Peripheral Arterial Disease among Adult Diabetic Patients Attending a Large Outpatient Diabetic Clinic at a National Referral Hospital in Uganda: A Descriptive Cross Sectional Study

    PubMed Central

    Mwebaze, Raymond Mbayo; Kibirige, Davis

    2014-01-01

    Background Peripheral arterial disease (PAD) is one of the recognised diabetic macro vascular complications. It is a marker of generalised systemic atherosclerosis and is closely associated with symptomatic coronary and cerebrovascular disease, hence significant morbidity and mortality. Among African adult diabetic populations, screening and diagnosis of PAD is frequently suboptimal. The aim of this study was to determine the prevalence and associated clinical factors of PAD in adult ambulatory diabetic patients attending the outpatient diabetic clinic of Mulago national referral and teaching hospital, Kampala Uganda. Methods In this descriptive cross sectional study, 146 ambulatory adult diabetic patients were studied. Information about their socio-demographic and clinical characteristics, fasting lipid profile status, blood pressure, glycated haemoglobin (HbA1c) levels and presence of albuminuria was collected using a pre tested questionnaire. Measurement of ankle brachial index (ABI) to assess for PAD, defined as a ratio less than 0.9 was performed using a portable 5–10 MHz Doppler device. Clinical factors associated with PAD were determined by comparing specific selected characteristics in patients with PAD and those without. Results The mean age/standard deviation of the study participants was 53.9/12.4 years with a male predominance (75, 51.4%). PAD was prevalent in 57 (39%) study participants. Of these, 34 (59.6%) had symptomatic PAD. The noted clinical factors associated with PAD in this study population were presence of symptoms of intermittent claudication and microalbuminuria. Conclusions This study documents a high prevalence of PAD among adult ambulatory Ugandan diabetic patients. Aggressive screening for PAD using ABI measurement in adult diabetic patients should be emphasised in Uganda especially in the presence of symptoms of intermittent claudication and microalbuminuria. PMID:25133533

  14. Illness self-concept in Type 1 diabetes: a cross-sectional view on clinical, demographic, and psychosocial correlates.

    PubMed

    Luyckx, Koen; Rassart, Jessica; Weets, Ilse

    2015-01-01

    The present study assessed the centrality of one's illness self-concept, or the degree to which chronic illness intrudes upon one's self, in a sample of 478 18-35-year-old patients with Type 1 diabetes. Confirmatory factor analysis indicated that illness self-concept centrality was a one-dimensional construct, despite the fact that three constituting components (i.e. pervasiveness, directionality, and illness self-consciousness) have been forwarded. Further, important demographic and clinical correlates of illness self-concept were identified: women, unemployed individuals, individuals with a lower educational level, and patients with an insulin pump had a more central illness self-concept. Finally, a series of correlation and regression analyses indicated that, despite the fact that illness self-concept centrality was negatively related to emotional stability, self-esteem, and diabetes integration, and positively to perceived consequences of diabetes, illness self-concept had unique predictive value over and above these variables for problem areas in diabetes and depressive symptoms. Implications and suggestions for future research are outlined. PMID:24666256

  15. Physical activity level and its clinical correlates in chronic obstructive pulmonary disease: a cross-sectional study

    PubMed Central

    2013-01-01

    Background Decreased physical activity is associated with higher mortality in subjects with COPD. The aim of this study was to assess clinical characteristics and physical activity levels (PALs) in subjects with COPD. Methods Seventy-three subjects with COPD (67?±?7 yrs, 44 female) with one-second forced expiratory volume percentage (FEV1%) predicted values of 43?±?16 were included. The ratio of total energy expenditure (TEE) and resting metabolic rate (RMR) was used to define the physical activity level (PAL) (PAL?=?TEE/RMR). TEE was assessed with an activity monitor (ActiReg), and RMR was measured by indirect calorimetry. Walking speed (measured over 30-meters), maximal quadriceps muscle strength, fat-free mass and systemic inflammation were measured as clinical characteristics. Hierarchical linear regression was applied to investigate the explanatory values of the clinical correlates to PAL. Results The mean PAL was 1.47?±?0.19, and 92% of subjects were classified as physically very inactive or sedentary. The walking speed was 1.02?±?0.23 m/s, the quadriceps strength was 31.3?±?11.2 kg, and the fat-free mass index (FFMI) was 15.7?±?2.3 kg/m2, identifying 42% of subjects as slow walkers, 21% as muscle-weak and 49% as FFM-depleted. The regression model explained 45.5% (p?correlates of physical activity. Further explorations of the longitudinal effects of the factors characterizing the most inactive subjects are warranted. PMID:24237876

  16. A cross-sectional survey of prevalence and correlates of suicidal ideation and suicide attempts among prisoners in New South Wales, Australia

    PubMed Central

    2012-01-01

    Background We aimed to estimate the prevalence of suicidal ideation and suicide attempt among prisoners in New South Wales, Australia; and, among prisoners reporting suicidal ideation, to identify factors associated with suicide attempt. Methods A cross-sectional design was used. Participants were a random, stratified sample of 996 inmates who completed a telephone survey. The estimated population prevalence of suicidal ideation and suicide attempt were calculated and differences by sex and Aboriginality were tested using ?2 tests. Correlates of suicidal ideation and suicide attempt were tested using logistic regression. Results One-third of inmates reported lifetime suicidal ideation and one-fifth had attempted suicide. Women and Aboriginal participants were significantly more likely than men and non-Aboriginal participants, respectively, to report attempting suicide. Correlates of suicidal ideation included violent offending, traumatic brain injury, depression, self-harm, and psychiatric hospitalisation. Univariate correlates of suicide attempt among ideators were childhood out-of-home care, parental incarceration and psychiatric hospitalization; however, none of these remained significant in a multivariate model. Conclusions Suicidal ideation and attempts are highly prevalent among prisoners compared to the general community. Assessment of suicide risk is a critical task for mental health clinicians in prisons. Attention should be given to ensuring assessments are gender- and culturally sensitive. Indicators of mental illness may not be accurate predictors of suicide attempt. Indicators of childhood trauma appear to be particularly relevant to risk of suicide attempt among prisoners and should be given attention as part of risk assessments. PMID:22225627

  17. Thermal Neutron Activation Cross Sections

    Microsoft Academic Search

    Leo Seren; Herbert N. Friedlander; Solomon H. Turkel

    1947-01-01

    The activation method of measuring slow neutron cross sections is discussed, in connection with the survey made at Argonne Laboratory. A table is given listing 131 activation cross sections of 65 elements and properties of the radio isotopes produced.

  18. Correlation between HIV viral load and aminotransferases as liver damage markers in HIV infected naive patients: a concordance cross-sectional study.

    PubMed

    Mata-Marín, José Antonio; Gaytán-Martínez, Jesús; Grados-Chavarría, Bernardo Horacio; Fuentes-Allen, José Luis; Arroyo-Anduiza, Carla Ileana; Alfaro-Mejía, Alfredo

    2009-01-01

    Abnormalities in liver function tests could be produced exclusively by direct inflammation in hepatocytes, caused by the human immunodeficiency virus (HIV). Mechanisms by which HIV causes hepatic damage are still unknown. Our aim was to determine the correlation between HIV viral load, and serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) as markers of hepatic damage in HIV naive infected patients. We performed a concordance cross-sectional study. Patients with antiviral treatment experience, hepatotoxic drugs use or co-infection were excluded. We used a Pearson's correlation coefficient to calculate the correlation between aminotransferases serum levels with HIV viral load. We enrolled 59 patients, 50 men and 9 women seen from 2006 to 2008. The mean (+/- SD) age of our subjects was 34.24 +/- 9.5, AST 37.73 +/- 29.94 IU/mL, ALT 43.34 +/- 42.41 IU/mL, HIV viral load 199,243 +/- 292,905 copies/mL, and CD4+ cells count 361 +/- 289 cells/mm(3). There was a moderately strong, positive correlation between AST serum levels and HIV viral load (r = 0.439, P < 0.001); and a weak correlation between ALT serum levels and HIV viral load (r = 0.276, P = 0.034); after adjusting the confounders in lineal regression model the correlation remained significant. Our results suggest that there is an association between HIV viral load and aminotransferases as markers of hepatic damage; we should improved recognition, diagnosis and potential therapy of hepatic damage in HIV infected patients. PMID:19878552

  19. Stigmatization of people living with HIV/AIDS by healthcare workers at a tertiary hospital in KwaZulu-Natal, South Africa: a cross-sectional descriptive study

    PubMed Central

    2013-01-01

    Background The issue of stigma is very important in the battle against HIV/AIDS in Africa since it may affect patient attendance at healthcare centres for obtaining antiretroviral (ARV) medications and regular medical check-ups. Stigmatization creates an unnecessary culture of secrecy and silence based on ignorance and fear of victimization. This study was designed to determine if there is external stigmatization of people living with HIV and AIDS (PLWHA) by health care workers (HCWs) at a tertiary hospital in KwaZulu-Natal (KZN) province, South Africa. The study investigated the impact of knowledge of HIV/AIDS by HCWs on treatment of patients, as well as the comfort level and attitude of HCWs when rendering care to PLWHA. Methods A descriptive cross sectional study was designed to collect data using an anonymous self-administered structured questionnaire from 334 HCWs. The study was conducted in clinical departments of a large multidisciplinary 922-bed tertiary care teaching hospital in Durban, KZN. Results Overall HCWs had an above average knowledge about HIV/AIDS although some gaps in knowledge were identified. Tests of statistical significance showed that there was association between level of education and knowledge of HIV/AIDs (p ? 0.001); occupation and knowledge of HIV/AIDS (p ? 0.001); and gender and knowledge of HIV/AIDS (p = 0.004). Test for comfort level was only significant for gender, with males showing more comfort and empathy when dealing with PLWHA (p = 0.003). The study also revealed that patients were sometimes tested for HIV without informed consent before surgery, due to fear of being infected, and there was some gossiping about patients' HIV status by HCWs, thereby compromising patient confidentiality. The majority of HCWs showed a willingness to report incidents of stigmatization and discrimination to higher authorities, for better monitoring and control. Conclusions Although knowledge, attitude and comfort level of HCWs taking care of PLWHA was above average, enforcement of existing antidiscrimination laws and continuing education in medical ethics and healthcare law, would greatly improve the performance of HCWs taking care of PLWHAs. More psychological support and counselling should be provided to HCWs, to further reduce the impact of stigmatization and discrimination against PLWHA. PMID:24564982

  20. 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

  1. 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.

  2. Proposal for the utilization of the total cross section covariances and its correlations with channel reactions for sensitivity and uncertainty analysis

    SciTech Connect

    Sabouri, P.; Bidaud, A. [Labratoire de Physique Subatomique et de Cosmologie, CNRS-IN2P3/UJF/INPG, Grenoble (France); Dabiran, S.; Buijs, A. [Dept. of Engineering Physics, McMaster Univ., Hamilton, ON (Canada)

    2012-07-01

    An alternate method for the estimation of the global uncertainty on criticality, using the total cross section and its covariances, is proposed. Application of the method with currently available covariance data leads to an unrealistically large prediction of the global uncertainty on criticality. New covariances for total cross section and individual reactions are proposed. Analysis with the proposed covariance matrices is found to result in a global uncertainty for criticality consistent with the traditional method. Recommendations are made to evaluators for providing total cross section covariances. (authors)

  3. 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

  4. Generalized x-ray scattering cross section from nonequilibrium plasmas

    SciTech Connect

    Gregori, G.; Glenzer, S. H.; Landen, O. L. [CCLRC, Rutherford Appleton Laboratory, Chilton, Didcot OX11 0QX, Great Britain and Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, Great Britain (United Kingdom); Lawrence Livermore National Laboratory, University of California, P.O. Box 808, California 94551 (United States)

    2006-08-15

    We propose a modified x-ray form factor that describes the scattering cross section in warm dense matter valid for both the plasma and the solid (crystalline) state. Our model accounts for the effect of lattice correlations on the electron-electron dynamic structure, as well as provides a smooth transition between the solid and the plasma scattering cross sections. In addition, we generalize the expression of the dynamic structure in the case of a two-temperature system (with different electron and ion temperatures). This work provides a unified description of the x-ray scattering processes in warm and dense matter, as the one encountered in inertial confinement fusion, laboratory astrophysics, material science, and high-energy density physics and it can be used to verify temperature relaxation mechanisms in such environments.

  5. The RAT SCAT cross-section facility

    Microsoft Academic Search

    H. C. Marlow; D. C. Watson; C. H. Van Hoozer; C. C. Freeny

    1965-01-01

    A description of the RAT SCAT cross-section facility is reported along with test results indicating measurement capabilities. The facility is described in terms of location, type of range, type of measurements, and the equipment complement. Measurement capabilities are presented in terms of vehicle dimensions and weight, relative to criteria such as system background, vehicle support background, nonplanar fields, and instrumentation

  6. Prevalence, patterns and correlates of alcohol consumption and its’ association with tobacco smoking among Sri Lankan adults: a cross-sectional study

    PubMed Central

    2014-01-01

    Background Most studies on alcohol consumption carried out in Sri Lanka are limited to single/few provinces in the island. The objective of this study was to determine the prevalence, patterns and correlates of alcohol consumption among a larger sample of adults in Sri Lanka. Methods This cross-sectional study was conducted in seven of all nine provinces in Sri Lanka, between 2005 and 2006. A nationally representative sample of 5000 adults aged ?18 years was selected using multi-stage random cluster sampling. Data of 4532 participants were collected using an interviewer administered questionnaire. Data analysis included chi-squared test, multiple logistic regression analysis and Spearman correlation using Stata/SE 10.0 (StataCorp LP., Texas, USA) software package. Results Males were 40%; mean age was 46.1 years (±15.1). The overall, urban and rural prevalence (95% CI) of current drinking was 23.7% (21.7 – 25.7), 29.5% (25.7 – 33.3) and 22.2% (19.8 – 24.7) respectively (p?=?0.001). Current (M: 48.1%, F: 1.2%, p?70 years age-group. Hazardous drinking was seen in 5.2% of men and 0.02% of women. Male sex, urban living and current smoking correlated with both current and hazardous drinking. Lower level of education, and age >70 years positively correlated with hazardous drinking. Conclusions Alcohol is predominantly a problem in Sri Lankan males. In males, both current and hazardous drinking positively correlated with urban living, white collar occupation, Burgher ethnicity and current smoking. Hazardous drinking positively correlated with lower level of education and older age. The data shown here are useful in planning interventions simultaneously targeting alcohol and tobacco. PMID:24938494

  7. A control-volume finite-element method for predicting flow and heat transfer in ducts of arbitrary cross sections - Part I: Description of the method

    SciTech Connect

    Prakash, C.; Patanker, S.V.

    1987-01-01

    A finite-element method for predicting flow through ducts of arbitrary and varying cross sections is presented. The governing differential equations are discretized using a control-volume approach. For this purpose, specially constructed three-dimensional control volumes are employed. The method is of the marching type and is based on a fully implicit formulation. Here, in part I of the paper, only the basic methodology is described; in the accompanying part II, results of application of the method to some test problems are presented.

  8. 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

  9. Charge and energy-dependence of the Gaussian description of the triply differential cross sections for equal-energy sharing photo-double-ionization of two-electrons ions

    SciTech Connect

    Otranto, S. [CONICET and Departamento de Fisica, Universidad Nacional del Sur, 8000 Bahia Blanca (Argentina); Garibotti, C.R. [CONICET and Centro Atomico Bariloche, 8400 S. C. de Bariloche (Argentina)

    2005-03-01

    We evaluate triply differential cross sections (TDCSs) for the photo-double-ionization (PDI) of He-like ions, and equal electron energy sharing, by using the SC3 model for the three-body final state. These cross sections are fitted with the usual dipolar Gaussian form which is found able to describe the theoretical TDCS, and could be applied for the interpretation of experimental data even at intermediate photon energies. We determine the dependence of the correlation factor on the excess energy (E{sub f}) and target nuclear charge (Z). We find that its width has an E{sub f}{sup 1/4} dependence near the atomic double-ionization threshold but departs from this law and attains a plateau as the excess energy increases. We compare our results with the predictions of classical and semiclassical Wannier approaches.

  10. Stratigraphic Cross Section of Northeast Texas

    NSDL National Science Digital Library

    Minor Keith

    Cretaceous sedimentary rocks of Northeast Texas provide important clues about paleogeography, paleotectonics, and sea level fluctuation. This website describes several of these rock units and the geologic information they supply. An unpublished report with a thorough discussion, map, cross section, and numerous references is provided. Specific topics include Cretaceous stratigraphy, lithostratigraphic and biostratigraphic correlation, ammonites, Western Interior Seaway, Skull Creek Seaway, paleogeography, and paleotectonics.

  11. Military Propensity and Enlistment: Cross-Sectional and Panel Analyses of Correlates and Predictors. Monitoring the Future Occasional Paper No. 41.

    ERIC Educational Resources Information Center

    Bachman, Jerald G.; Segal, David R.; Freedman-Doan, Peter; O'Malley, Patrick M.

    This study examines why some young men and women choose military service as well as what factors lead to successful enlisting among those who choose military service. It examines these questions using cross-sectional and longitudinal panel survey data from large nationwide samples of high school seniors, many of whom were followed into young…

  12. Self-reported sexually transmitted infections and their correlates among men who have sex with men in Norway: an Internet-based cross-sectional survey

    PubMed Central

    2010-01-01

    Background The incidences of reportable sexually transmitted infections (STI) among men who have sex with men (MSM) have increased since the late 1990 s in Norway. The objectives of our study were to assess factors, associated with recent selected STI among MSM, living in Norway in order to guide prevention measures. Methods We conducted a cross-sectional Internet-based survey during 1-19 October 2007 among members of a MSM-oriented Norwegian website using an anonymous questionnaire on demographics, sexual behaviour, drug and alcohol use, and STI. The studied outcomes were gonorrhoea, syphilis, HIV or Chlamydia infection in the previous 12 months. Associations between self-reported selected STI and their correlates were analysed by multivariable Poisson regression. P value for trend (p-trend), adjusted prevalence ratios (PR) with 95% confidence intervals [] were calculated. Results Among 2430 eligible 16-74 years old respondents, 184 (8%) reported having had one of the following: syphilis (n = 17), gonorrhoea (n = 35), HIV (n = 42) or Chlamydia (n = 126) diagnosed in the past 12 months. Reporting Chlamydia was associated with non-western background (PR 2.8 [1.4-5.7]), number of lifetime male partners (p-trend < 0.001), unsafe sex under the influence of alcohol (PR 1.8 [1.1-2.9]) and with younger age (p-trend = 0.002). Reporting gonorrhoea was associated with unrevealed background (PR 5.9 [1.3-26.3]), having more than 50 lifetime male partners (PR 4.5 [1.3-15.6]) and more than 5 partners in the past 6 months (PR 3.1 [1.1-8.8]), while mid-range income was protective (PR 0.1 [0.0-0.6]). Reporting HIV was associated with residing in Oslo or Akershus county (PR 2.3 [1.2-4.6]), non-western background (PR 5.4 [1.9-15.3]), unrevealed income (PR 10.4 [1.5-71.4]), number of lifetime male partners (p-trend < 0.001) and being under the influence of selected drugs during sex in the past 12 months (PR 5.2 [2.7-11.4]). In addition, the frequency of feeling drunk was reversibly associated with HIV. Conclusions Our study demonstrates different associations of demographic and behavioural factors with different STI outcomes in the study population. Number of lifetime male partners was the most important potential predictor for Chlamydia and HIV. The STI prevention efforts among MSM should focus on Oslo and Akershus, promote safe sex practices and tackle sex-related drug and alcohol use. PMID:20815931

  13. Self-reported sexually transmitted infections and their correlates among men who have sex with men in Norway: an Internet-based cross-sectional survey

    Microsoft Academic Search

    Irena Jakopanec; Barbara Schimmer; Andrej M Grjibovski; Elise Klouman; Preben Aavitsland

    2010-01-01

    BACKGROUND: The incidences of reportable sexually transmitted infections (STI) among men who have sex with men (MSM) have increased since the late 1990 s in Norway. The objectives of our study were to assess factors, associated with recent selected STI among MSM, living in Norway in order to guide prevention measures. METHODS: We conducted a cross-sectional Internet-based survey during 1-19

  14. 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.

  15. Family and home correlates of children's physical activity in a multi-ethnic population: the cross-sectional child heart and health study in england (CHASE)

    Microsoft Academic Search

    Alison M McMinn; Esther MF van Sluijs; Claire M Nightingale; Simon J Griffin; Derek G Cook; Chris G Owen; Alicja R Rudnicka; Peter H Whincup

    2011-01-01

    Background  The influence of the family and home environment on childhood physical activity (PA) and whether this differs between ethnic\\u000a groups remains uncertain. This paper investigates associations between family and home factors and childhood PA in a multi-ethnic\\u000a population and explores whether associations differ between ethnic groups.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Cross-sectional study of 9-10 year-old schoolchildren, in which PA was objectively measured by Actigraph

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

    E-print Network

    Carlson, B V; Kerman, A K

    2015-01-01

    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.

  17. 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.

  18. ABSORPTION CROSS SECTION OF STABLE, LOW CROSS SECTION FISSION PRODUCTS

    Microsoft Academic Search

    Breslauer

    1959-01-01

    A record of the relatively stable, low cross section fissibn products ; available on ANP nuclear data tape is presented for conventional reactor ; calculations. The record is based on data included in the Geneva conference ; paper by Gordeev and Pupko. The label slag is applied to fission products. ; (J.R.D.);

  19. NEUTRON-ACTIVATION CROSS SECTIONS

    Microsoft Academic Search

    J. A. Miskel; K. V. Marsh; M. Lindner; R. J. Nagle

    1961-01-01

    Neutron-activation cross sections for Hf¹⁸°, Ta¹⁸¹, W\\/sup ; 186\\/ Au¹⁹⁷, and Th²³² were measured. The results were compared ; with those calculated using the statistical theory of nuclear reactions and with ; resuits obtained by other investigators. (J.R.D.);

  20. FISSION-PRODUCT CAPTURE CROSS SECTIONS

    Microsoft Academic Search

    J. D. Garrison; B. W. Roos

    1962-01-01

    Experimental measurements of fission product capture cross sections and ; statistical estimates of capture cross sections for energies at which no ; measurements have been made yielded a set of group cross sections for primary and ; secondary fission products covering the complete range of energies of interest ; for reactor calculations. Capture cross sections and fission product yield ;

  1. LUMEN Cross-Section Tutorial

    NSDL National Science Digital Library

    McNulty, John A.

    The Loyola University Medical Education Network (LUMEN) presents this anatomy tutorial. The site is divided up into categories of cross-sectional images of the human body: Head and Neck, Upper Limb, male and female Thorax, Abdomen, male and female Pelvis, and Lower Limb. By clicking on each section, users select a cross-section of that part of the anatomy, and by clicking on each number, can find out the specific name of that area. Users can also choose to see an illustration of the area (by choosing â??Imageâ?), or an image from a CAT scan (by choosing â??CTâ?). This is an excellent resource for students in any health care or allied medical field, including nursing or nursesâ?? aides, patient care assistants, and diagnostic imaging technicians.

  2. Neutron-Activation Cross Sections

    Microsoft Academic Search

    J. A. Miskel; K. V. Marsh; M. Lindner; R. J. Nagle

    1962-01-01

    Neutron-activation cross sections have been measured for five target nuclei, Hf180, Ta181, W186, Au197, and Th232, over a neutron energy range from 0.030 to 4.0 MeV. The experimental results are compared with values calculated from the statistical theory of nuclear reactions. Values of the constant Cn in the approximate level density formula pn=Cnexp[2(aE)12] are obtained for these isotopes from a

  3. Characteristics and treatment outcomes of tuberculosis patients who “transfer-in” to health facilities in Harare City, Zimbabwe: a descriptive cross-sectional study

    PubMed Central

    2012-01-01

    Background Zimbabwe is among the 22 Tuberculosis (TB) high burden countries worldwide and runs a well-established, standardized recording and reporting system on case finding and treatment outcomes. During TB treatment, patients transfer-out and transfer-in to different health facilities, but there are few data from any national TB programmes about whether this process happens and if so to what extent. The aim of this study therefore was to describe the characteristics and outcomes of TB patients that transferred into Harare City health department clinics under the national TB programme. Specific objectives were to determine i) the proportion of a cohort of TB patients registered as transfer-in, ii) the characteristics and treatment outcomes of these transfer-in patients and iii) whether their treatment outcomes had been communicated back to their respective referral districts after completion of TB treatment. Methods Data were abstracted from patient files and district TB registers for all transfer-in TB patients registered from January to December 2010 within Harare City. Descriptive statistics were calculated. Results Of the 7,742 registered TB patients in 2010, 263 (3.5%) had transferred-in: 148 (56%) were males and overall median age was 33 years (IQR, 26–40). Most transfer-in patients (74%) came during the intensive phase of TB treatment, and 58% were from rural health-facilities. Of 176 patients with complete data on the time period between transfer-in and transfer-out, only 85 (48%) arrived for registration in Harare from referral districts within 1 week of being transferred-out. Transfer-in patients had 69% treatment success, but in 21% treatment outcome status was not evaluated. Overall, 3/212 (1.4%) transfer-in TB patients had their TB treatment outcomes reported back to their referral districts. Conclusion There is need to devise better strategies of following up TB patients to their referral Directly Observed Treatment (DOT) centres from TB diagnosing centres to ensure that they arrive promptly and on time. Recording and reporting of information must improve and this can be done through training and supervision. Use of mobile phones and other technology to communicate TB treatment outcomes back to the referral districts would seem the obvious way to move forward on these issues. PMID:23150928

  4. Deeply virtual Compton Scattering cross section measured with CLAS

    SciTech Connect

    Guegan, Baptistse [Institut de Physique Nucleaire, Orsay

    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.

  5. Correlates of consistent condom use among men who have sex with men recruited through the Internet in Huzhou city: a cross-sectional survey

    PubMed Central

    2013-01-01

    Background There is growing evidence that men who have sex with men (MSM) are currently a group at high risk of HIV infection in China. Our study aims to know the factors affecting consistent condom use among MSM recruited through the internet in Huzhou city. Methods An anonymous cross-sectional study was conducted by recruiting 410 MSM living in Huzhou city via the Internet. The socio-demographic profiles (age, education level, employment status, etc.) and sexual risk behaviors of the respondents were investigated. Bivariate logistic regression analyses were performed to compare the differences between consistent condom users and inconsistent condom users. Variables with significant bivariate between groups’ differences were used as candidate variables in a stepwise multivariate logistic regression model. All statistical analyses were performed using SPSS for Windows 17.0, and a p value?

  6. 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.

  7. Gait speed correlates in a multiracial population of community-dwelling older adults living in Brazil: a cross-sectional population-based study

    PubMed Central

    2013-01-01

    Background Gait speed is a strong predictor of a wide range of adverse health outcomes in older adults. Mean values for gait speed in community-dwelling older adults vary substantially depending on population characteristics, suggesting that social, biological, or health factors might explain why certain groups tend to self-select their gait speed in different patterns. The vast majority of studies reported in the literature present data from North American and European populations. There are few population-based studies from other regions with a different ethnicity and/or social and health conditions. To address this, the present study identified the mean usual and fast gait speeds in a representative multiracial population of community-dwelling older adults living in a developing country, and explored their association with sociodemographic, mental and physical health characteristics. Methods This was a cross-sectional population-based study of a sample of 137 men and 248 women, aged 65 years and over. Usual gait speed and fast gait speed were measured on a 4.6 m path. Participants were classified into slow, intermediate, and faster groups by cluster analysis. Logistic regression analysis was used to estimate the independent effect of each factor on the odds of presenting with a slower usual and slower fast gait speeds. Results Participants had a mean (SD) usual gait speed of 1.11 (0.27) m/s and a mean fast gait speed of 1.39 (0.34) m/s. We did not observe an independent association between gait speed and race/ethnicity, educational level, or income. The main contributors to present a slower usual gait speed were low physical activity level, stroke, diabetes, urinary incontinence, high concern about falling, and old age. A slower fast gait speed was associated with old age, low physical activity, urinary incontinence and high concern about falling. Conclusion A multiracial population of older adults living in a developing country showed a similar mean gait speed to that observed in previously studied populations. The results suggest that low physical activity, urinary incontinence and high concern about falling should not be neglected and may help identify those who might benefit from early intervention. PMID:23448191

  8. NEUTRON ACTIVATION CROSS SECTIONS AT 25 Kev

    Microsoft Academic Search

    Rex Booth; William Ball; Malcolm MacGregor

    1958-01-01

    Neutron activation cross sections have been measured at 25 kev for 31 ; isotopes. An Sb-Be photoneutron source was used, and thermal activations served ; to calibrate the beta- and gamma-detector efficiencies. The cross sections were ; measnred relative to iodine. A comparison was made between measured cross ; sections and predictions based on known low-energy resonance parameters. (auth);

  9. Actinide cross section program at ORELA

    Microsoft Academic Search

    Dabbs; J. W. T

    1980-01-01

    The actinide cross section program at ORELA, the Oak Ridge Electron Linear Accelerator, is aimed at obtaining accurate neutron cross sections (primarily fission, capture, and total) for actinide nuclides which occur in fission reactors. Such cross sections, measured as a function of neutron energy over as wide a range of energies as feasible, comprise a data base that permits calculated

  10. Neutron Activation Cross Sections at 25 kev

    Microsoft Academic Search

    Rex Booth; William P. Ball; Malcolm H. MacGregor

    1958-01-01

    Neutron activation cross sections have been measured at 25 kev for 31 isotopes. An Sb-Be photoneutron source was used, and thermal activations served to calibrate the beta- and gamma-detector efficiencies. The cross sections were measured relative to iodine. A comparison was made between measured cross sections and predictions based on known low-energy resonance parameters.

  11. UNCLASSIFIED CROSS SECTIONS FOR FAST REACTOR CALCULATIONS

    Microsoft Academic Search

    Bjorklund

    1953-01-01

    ABS>A compilation of estimated capture and total cross sections is given ; for 47 elements. Transport and inelastic cross sections are tabulated for ; various elements and curves of these cross sections vs. pertinent nuclear ; properties are given. (C.J.G.);

  12. 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

  13. Correlation of exhaled nitric oxide, nasal nitric oxide and atopic status: A cross-sectional study in bronchial asthma and allergic rhinitis

    PubMed Central

    Gupta, Nitesh; Goel, Nitin; Kumar, Raj

    2014-01-01

    Objective: Exhaled nitric oxide (FENO) and nasal nitric oxide (n NO) measurement is an area of ongoing research in the study of airway inflammation. The atopic status is known to influence the levels of FENO and n NO. This study was undertaken to study the relationship between nitric oxide measurements in bronchial asthma and allergic rhinitis along with their correlation with atopic profile of Indian population. Materials and Methods: Ninety subjects were recruited for the study comprising of 25 each of bronchial asthma (BA), allergic rhinitis (AR), bronchial asthma with allergic rhinitis (BA-AR) and 15 healthy controls. These were assessed for atopy and exhaled breath analysis of nitric oxide. The measurements of FENO and n NO levels were done using NIOX chemiluminescence analyzer. Atopy was assessed by skin prick testing (SPT) against 58 common aero-allergens and subjects with ?1 positive SPT were labeled as atopic. Results: The BA-AR and BA groups had higher FENO levels in comparison to the control (P < 0.05) and AR group (P < 0.05). The AR and BA-AR groups had higher n NO levels compared to the control group (P < 0.05) and BA group (P < 0.05). The increasing FENO levels significantly correlated with the increase in the number of allergen sensitization in patients suffering from BA-AR (P < 0.05). However, the BA group showed a weaker positive correlation (P = 0.07). Conclusion: FENO is a non-invasive marker of airway inflammation. Also, FENO levels correlate with presence and degree of atopy in BA and AR. Simultaneously, n NO could be a surrogate marker of rhinitis. PMID:25378841

  14. Clinical correlation of magnetic resonance imaging with symptom complex in prolapsed intervertebral disc disease: A cross-sectional double blind analysis

    PubMed Central

    Bajpai, Jeetendra; Saini, Sumit; Singh, Rakhi

    2013-01-01

    Introduction: Low backache (LBA) is one of the most common problems and herniated lumbar disc is one of the most commonly diagnosed abnormalities associated with LBA. Disc herniation of the same size may be asymptomatic in one patient and can lead to severe nerve root compromise in another patient. Objective: To evaluate correlation between the clinical features of disc collapse and magnetic resonance imaging (MRI) finding to determine the clinical importance of anatomical abnormalities identified by MRI technique. Summary: From January 2010 to January 2012, 75 otherwise healthy patients (43 males 32 females) between the age of 19 and 55 years (average age was 44.5 years) with low back pain and predominant complaint of root pain who presented to our clinic were included in the study. Materials and Methods: Proper screening was done to rule out previous spine affection and subjected to MRI. Results: The results were analyzed under four headings viz. disc herniation, disc degeneration, thecal sac deformation and neural foramen effacement. All patients had a visual analog score (VAS) score more than 6. The interrater correlation coefficient kappa was calculated to be k=0.51. There were total 44 patients with herniation, 25 patients had mild, one patient had moderate degree of thecal sac deformation, 21 patients had one or more levels of foraminal effacement by the herniated tissue, 100% of the patients had disc degeneration ranging from grade 1 to 3 at different levels; and 48 patients (64%) had radiculopathy, six (8%) patients had bilateral and others had ipsilateral affection. Conclusion: In our study, the correlation was made between clinical findings and MRI findings. It can safely be concluded that treating physician should put more emphasis on history, clinical examination, and make the inference by these and then should correlate the clinical findings with that of MRI to reach a final diagnosis. PMID:24381451

  15. Estimation and correlation of salivary thiocyanate levels in healthy and different forms of tobacco users having chronic periodontitis: A cross-sectional biochemical study

    PubMed Central

    Kalburgi, C. Veena; Naik, K. Lavanya; Kokatnur, M. Vijayalaxmi; Warad, Shivaraj

    2014-01-01

    Background: Periodontitis is a common inflammatory disease with complex and multi-factorial origin. Tobacco usage has shown its adverse effect on periodontal health. Various components within saliva not only protect the integrity of oral tissues, but also provide clues to local and systemic diseases and conditions. Salivary thiocyanate (SCN) has been shown to be a chemical indicator in smokers and smokeless tobacco users. Noninvasive nature of salivary testing has made it an attractive and effective alternative to blood and urine testing. Limited studies are there comparing and correlating the salivary SCN levels in smokers with chronic periodontitis (CP). However, no studies show correlation of salivary SCN among gutka chewers with CP. Aims and Objectives: The objective of the following study is to estimate, compare, and correlate the SCN levels in periodontally healthy, CP, smokers with CP and gutka chewers with CP subjects. Materials and Methods: Study includes 120 subjects with age 18-55 years, categorized as periodonally healthy (n = 30), CP (n = 30), smokers (n = 30), and gutka chewers (n = 30) with CP. Required clinical parameters such as gingival index, probing depth and clinical attachment loss were recorded and salivary SCN levels were estimated through ultraviolet-spectrophotometer. Results: Mean salivary SCN level were shown to be higher among smokers and gutka chewers with CP as compared to healthy and CP alone. Conclusion: The present study exhibited the significant increase in salivary SCN levels among smokers and gutka chewers when compared to others, concluding that the analysis of salivary SCN levels could be used as an adjunctive means of diagnosis. PMID:24963243

  16. 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

  17. Revision 1 Size and position of the healthy meniscus, and its Correlation with sex, height, weight, and bone area- a cross-sectional study

    PubMed Central

    2011-01-01

    Background Meniscus extrusion or hypertrophy may occur in knee osteoarthritis (OA). However, currently no data are available on the position and size of the meniscus in asymptomatic men and women with normal meniscus integrity. Methods Three-dimensional coronal DESSwe MRIs were used to segment and quantitatively measure the size and position of the medial and lateral menisci, and their correlation with sex, height, weight, and tibial plateau area. 102 knees (40 male and 62 female) were drawn from the Osteoarthritis Initiative "non-exposed" reference cohort, including subjects without symptoms, radiographic signs, or risk factors for knee OA. Knees with MRI signs of meniscus lesions were excluded. Results The tibial plateau area was significantly larger (p < 0.001) in male knees than in female ones (+23% medially; +28% laterally), as was total meniscus surface area (p < 0.001, +20% medially; +26% laterally). Ipsi-compartimental tibial plateau area was more strongly correlated with total meniscus surface area in men (r = .72 medially; r = .62 laterally) and women (r = .67; r = .75) than contra-compartimental or total tibial plateau area, body height or weight. The ratio of meniscus versus tibial plateau area was similar between men and women (p = 0.22 medially; p = 0.72 laterally). Tibial coverage by the meniscus was similar between men and women (50% medially; 58% laterally), but "physiological" medial meniscal extrusion was greater in women (1.83 ± 1.06mm) than in men (1.24mm ± 1.18mm; p = 0.011). Conclusions These data suggest that meniscus surface area strongly scales with (ipsilateral) tibial plateau area across both sexes, and that tibial coverage by the meniscus is similar between men and women. PMID:22035074

  18. Comparison of intraclass correlation coefficient estimates and standard errors between using cross-sectional and repeated measurement data: the Safety Check cluster randomized trial.

    PubMed

    Ip, Edward H; Wasserman, Richard; Barkin, Shari

    2011-03-01

    Designing cluster randomized trials in clinical studies often requires accurate estimates of intraclass correlation, which quantifies the strength of correlation between units, such as participants, within a cluster, such as a practice. Published ICC estimates, even when available, often suffer from the problem of wide confidence intervals. Using data from a national, randomized, controlled study concerning violence prevention for children--the Safety Check--we compare the ICC values derived from two approaches only baseline data and using both baseline and follow-up data. Using a variance component decomposition approach, the latter method allows flexibility in handling complex data sets. For example, it allows for shifts in the outcome variable over time and for an unbalanced cluster design. Furthermore, we evaluate the large-sample formula for ICC estimates and standard errors using the bootstrap method. Our findings suggest that ICC estimates range from 0.012 to 0.11 for providers within practice and range from 0.018 to 0.11 for families within provider. The estimates derived from the baseline-only and repeated-measurements approaches agree quite well except in cases in which variation over repeated measurements is large. The reductions in the widths of ICC confidence limits from using repeated measurement over baseline only are, respectively, 62% and 42% at the practice and provider levels. The contribution of this paper therefore includes two elements, which are a methodology for improving the accuracy of ICC, and the reporting of such quantities for pediatric and other researchers who are interested in designing clustered randomized trials similar to the current study. PMID:21070889

  19. 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

  20. 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

  1. 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

    2015-01-01

    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

  2. Endurance-training in healthy men is associated with lesser exertional breathlessness that correlates with circulatory-muscular conditioning markers in a cross-sectional design.

    PubMed

    Plantier, Laurent; Al Dandachi, Ghanima; Londner, Cécile; Caumont-Prim, Aurore; Chevalier-Bidaud, Brigitte; Toussaint, Jean-François; Desgorces, François-Denis; Delclaux, Christophe

    2014-01-01

    Whether exertional dyspnoea can be attributed to poor circulatory-muscular conditioning is a difficult clinical issue. Because criteria of poor conditioning such as low oxygen pulse, low ventilatory threshold or high heart rate/oxygen consumption slope can be observed in heart or lung diseases and are not specific to conditioning, we assessed the relationships between physical exercise, conditioning and exertional breathlessness in healthy subjects, in whom the aforementioned criteria can confidently be interpreted as reflecting conditioning. To this end, healthy males with either low (inactive men, n = 31) or high (endurance-trained men, n = 31) physical activity evaluated using the International Physical Activity Questionnaire (IPAQ) underwent spirometry and incremental exercise testing with breathlessness assessment using Borg scale. No significant breathlessness was reported before the ventilatory threshold in the two groups. Peak breathlessness was highly variable, did not differ between the two groups, was not related to any conditioning criterion, but correlated with peak respiratory rate. Nevertheless, endurance-trained subjects reported lower breathlessness at the same ventilation levels in comparison with inactive subjects. Significant but weak associations were observed between isoventilation breathlessness and physical activity indices (Borg at 60 L/min and total IPAQ scores, rho = -0.31, p = 0.020), which were mainly attributable to the vigorous domain of physical activity, as well as with conditioning indices (Borg score at 60 L.min(-1) and peak oxygen pulse or heart rate/oxygen consumption slope, rho = -0.31, p = 0.021 and rho = 0.31, p = 0.020; respectively). In conclusion, our data support a weak relationship between exertional breathlessness and circulatory-muscular conditioning, the later being primarily related to vigorous physical activity. PMID:25157332

  3. 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

  4. [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.

  5. 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.

  6. Theoretical antideuteron-nucleus absorptive cross sections

    NASA Technical Reports Server (NTRS)

    Buck, W. W.; Norbury, J. W.; Townsend, L. W.; Wilson, J. W.

    1993-01-01

    Antideuteron-nucleus absorptive cross sections for intermediate to high energies are calculated using an ion-ion optical model. Good agreement with experiment (within 15 percent) is obtained in this same model for (bar p)-nucleus cross sections at laboratory energies up to 15 GeV. We describe a technique for estimating antinucleus-nucleus cross sections from NN data and suggest that further cosmic ray studies to search for antideuterons and other antinuclei be undertaken.

  7. 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

  8. 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

  9. The Primitive Streak, Cross Section

    NSDL National Science Digital Library

    PhD Jack D Thatcher (West Virginia School of Osteopathic Medicine Structural Biology)

    2011-06-23

    This FlashTM animation is the third of a seven part series that presents the primitive streak from different angles. This installment displays the cross section, which is conducive to observing invagination. Epiblast cells ingress through the middle of the germ disc, to differentiate into either endoderm or mesenchymal mesoderm. The endoderm proliferates to drive the hypoblast into the extraembryonic endoderm of the yolk sac. The mesenchyme spreads between the epiblast and endoderm. Although not drawn to scale, the progressive thickening from lateral to paraxial mesoderm is depicted. To open the animation using Internet Explorer follow these steps. (1.) Click the link for the animation. (2.) A dialog box may pop up that begins with the statement "Windows cannot open this file:" If this box does not appear proceed to step four. If it does choose "Select the program from a list," then click OK. (3.) Another dialog box will pop up that lists different programs. Make sure "Internet Explorer" is selected, then click OK. (4.) Internet Explorer will pop up. Beneath the toolbars at the top of the window a yellow bar will appear that reads "To help protect your security, Internet Explorer has restricted this webpage from running scripts or Active X controls that could access your computer. Click here for options..." Pass the cursor over this yellow bar and click the right mouse button. (5.) A dialog box will pop up. Left click the option "Allow Blocked Content." (6.) Another dialog box will appear labeled "Security Warning" asking you to confirm that you want to run the content. Click "Yes." (7.) The Flash animation will appear in the Internet Explorer Window. (8.) Instructions for navigating the lesson are provided by the first frame of the animation.

  10. 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.

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

    SciTech Connect

    Fang, D. Q.; Ma, Y. G.; Cai, X. Z.; Tian, W. D.; Wang, H. W. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Post Office Box 800-204, Shanghai 201800 (China)

    2010-04-15

    We study the relation between neutron removal cross section (sigma{sub -N}) and neutron skin thickness for finite neutron-rich nuclei using the statistical abrasion ablation 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{sub -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 neutron skin thickness in neutron-rich nuclei.

  12. Quality at general practice consultations: cross sectional survey

    Microsoft Academic Search

    John G R Howie; David J Heaney; Margaret Maxwell; Jeremy J Walker; George K Freeman; Harbinder Rai

    1999-01-01

    Objectives To measure quality of care at general practice consultations in diverse geographical areas, and to determine the principal correlates associated with enablement as an outcome measure. Design Cross sectional multipractice questionnaire based study. Setting Random sample of practices in four participating regions: Lothian, Coventry, Oxfordshire,

  13. Atlas of Photoneutron Cross Sections Obtained with Monoenergetic Photons

    Microsoft Academic Search

    S. S. Dietrich; B. L. Berman

    1988-01-01

    Photoneutron cross-section and integrated cross-section data obtained with monoenergetic photons are presented in a uniform format. All of the measured partial photoneutron cross sections, the total photoneutron cross section, and the photoneutron yield cross section are plotted as functions of the incident photon energy, as are the integrated photoneutron cross sections and their first and second moments. The values of

  14. Nuclear Cross Sections For Fast Reactors

    Microsoft Academic Search

    S. Yiftah; M. Sieger

    1964-01-01

    The 16-group YOM cross section set for fast reactor analysis has been widely used by fast reactor centers during the last three years. Since its publication at the end of 1960, a considerable amount of experimental results as well as some theoretical investigations have become available. Also, various 'users' have kindly sent queries and remarks on the different cross sections

  15. Radiation pressure cross section for fluffy aggregates

    Microsoft Academic Search

    Hiroshi Kimura; Ingrid Mann

    1998-01-01

    —We apply the discrete dipole approximation (DDA) to estimate the radiation pressure cross section for fluffy aggregates by computing the asymmetry parameter and the cross sections for extinction and scattering. The ballistic particle–cluster aggregate and the ballistic cluster–cluster aggregate consisting of either dielectric or absorbing material are considered to represent naturally existing aggregates. We show that the asymmetry parameter perpendicular

  16. Surface interpolation from sparse cross-sections

    E-print Network

    Drummond, Tom

    Surface interpolation from sparse cross-sections using region correspondence G.M. Treece, R complex. In this paper, an algorithm is presented which can interpolate a surface through sparse, complex cross-sections. This is an extension of maximal disc guided interpolation [25], which is itself based

  17. Temperature dependence of unshielded cross-sections in multigroup cross-section sets

    Microsoft Academic Search

    V. Gopalakrishnan

    2000-01-01

    The self-shielding factor method in the multigroup approach is well known in Reactor Physics. The temperature and background dependent neutron cross-sections are conventionally represented in a problem-independent multigroup cross-section set by specifying for each group and reaction the unshielded cross-section (at 0 K) along with a set of self-shielding factors for various background cross-sections and temperatures. Usually the unshielded group

  18. 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.

  19. Report on 238Pu(n,x) surrogate cross section measurement

    SciTech Connect

    Burke, J T; Ressler, J J; Henderson, R A; Scielzo, N D; Escher, J E; Thompson, I J; Gostic, J; Bleuel, D; Weideking, M; Bernstein, L A

    2010-03-31

    The goal of this year's effort is to measure the {sup 238}Pu(n,f) and {sup 238}Pu(n,2n) cross section from 100 keV to 20 MeV. We designed a surrogate experiment that used the reaction {sup 239}Pu(a,a{prime}x) as a surrogate for {sup 238}Pu(n,x). The experiment was conducted using the STARS/LIBERACE experimental facility located at the 88 Inch Cyclotron at Lawrence Berkeley National Laboratory in January 2010. A description of the experiment and status of the data analysis is given. In order to obtain a reliable {sup 238}Pu(n,x) cross section we designed the experiment using the surrogate ratio technique. This technique allows one to measure a desired, unknown, cross section relative to a known cross section. In the present example, the {sup 238}Pu(n,x) cross section of interest is determined relative to the known {sup 235}U(n,x) cross section. To increase confidence in the results, and to reduce overall uncertainties, we are also determining the {sup 238}Pu(n,x) cross section relative to the known {sup 234}U(n,x) cross section. The compound nuclei of interest for this experiment were produced using inelastic alpha scattering. For example, {sup 236}U(a,a{prime}x) served as a surrogate for {sup 235}U(n,x); analogous reactions were considered for the other cross sections. Surrogate experiments determine the probabilities for the decay of the compound nuclei into the various channels of interest (fission, gamma decay) by measuring particle-fission (p-f) or particle?gamma (p?g) reaction spectra. By comparing the decay probabilities associated with the unknown cross section to that of a known cross section it is possible to obtain the ratio of these cross sections and thus determine the unknown, desired cross section.

  20. Calculated medium-energy fission cross sections

    SciTech Connect

    Arthur, E.D.; Young, P.G.

    1988-01-01

    Calculations were made of neutron-induced fission cross sections on /sup 238/U and /sup 237/Np to compare with new data available up to 100 MeV. This process also produced fission barrier parameters for neptunium and uranium compound systems required for calculation of p + /sup 238/U fission cross sections. To achieve reasonable agreement with higher energy neutron-induced fission data, a phenomenological enhancement to barrier heights based upon the average angular momentum of the compound system was required. These calculational procedures resulted in predictions of /sup 238/U(p,f) cross sections that agree well with available data. 7 refs., 2 figs.

  1. 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.

  2. Preliminary observations of cusp cross-section pinch

    Microsoft Academic Search

    M. A. M. Kashani; T. Miyamoto

    2004-01-01

    Summary form only given. In this paper, we introduce a cusp cross-section pinch (CCSP) as an example of geometrical stabilization, and give the description of constructed device. The CCSP device is, consisted of two sheet Z-pinch devices arranged face to face. Each sheet Z-pinch device is like a coaxial gun, which is elongated to one direction. The plasma sheets are

  3. Verification of the Rayleigh scattering cross section

    Microsoft Academic Search

    Sayan Chakraborti

    2007-01-01

    A simple experiment is described for the direct determination of the wavelength dependence of the Rayleigh scattering cross section using the classic example of the blue sky. Suggestions for inclusion into an undergraduate lab are discussed.

  4. Fragmentation Cross Sections in Heavy Ion Collisions

    NASA Astrophysics Data System (ADS)

    Bian, Bao-An; Zhang, Feng-Shou; Zhou, Hong-Yu

    The fragment cross sections are calculated for reactions of Ne collisions with C, Al, Cu, Sn, Ta, and Pb targets at 600 Mev/nucleon using the the isospin-dependent Boltzmann-Langevin equation. We found that the production cross sections for fragments Z = 2 to 9 are qualitatively reproduced by the present calculations except for C target. In order to understand the effects of heavy ion interaction with biomolecules well, we calculate the fragmentation cross sections for reactions of 12C + 2H, 12C, 14N, 16O at beam energies from 50 to 100 MeV/nucleon. It is found that fragment species increase approximately with increasing target mass. The obvious increment of the fragment cross sections for heavier targets at the beam energies from 50 to 80 MeV/nucleon are shown.

  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. 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.

  7. 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 line path and the target...

  8. 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.

  9. Strength and cross-sectional area of human skeletal muscle.

    PubMed Central

    Maughan, R J; Watson, J S; Weir, J

    1983-01-01

    The maximum voluntary force (strength) which could be produced by the knee-extensor muscles, with the knee held at a right angle, was measured in a group of healthy young subjects comprising twenty-five males and twenty-five females. Both legs were tested: data from the stronger leg only for each subject were used in the present study. Computed tomography was used to obtain a cross-sectional image of the subjects' legs at mid-thigh level, measured as the mid-point between the greater trochanter and upper border of the patella. The cross-sectional area of the knee-extensor muscles was determined from the image obtained by computer-based planimetry. The subjects' height and weight were measured. An estimate of body fat content was obtained from measurements of skinfold thicknesses and used to calculate lean body mass. Male subjects were taller (P less than 0.001), heavier (P less than 0.001), leaner (P less than 0.001) and stronger (P less than 0.001) than the female subjects. No significant correlation was found to exist between strength of the knee-extensor muscles and body weight in the male or in the female subjects. In the male subjects, but not in the female group, there was a positive correlation (r = 0.50; P less than 0.01) between strength and lean body mass. Muscle cross-sectional area of the male subjects was greater than that of the female subjects (P less than 0.001). The ratio of strength to cross-sectional area for the male was 9.49 +/- 1.34 (mean +/- S.D.). This is greater but not significantly so, than that for females (8.92 +/- 1.11). In both male and female groups, there was a significant (P less than 0.01) positive correlation between muscle strength and cross-sectional area. A wide variation in the ratio of strength to muscle cross-sectional area was observed. This variability may be a result of anatomical differences between subjects or may result from differences in the proportions of different fibre types in the muscles. The variation between subjects is such that strength is not a useful predictive index of muscle cross-sectional area. Images Plate 1 PMID:6875963

  10. Fragmentation Cross Sections in Heavy Ion Collisions

    Microsoft Academic Search

    Bao-An Bian; Feng-Shou Zhang; Hong-Yu Zhou

    2008-01-01

    The fragment cross sections are calculated for reactions of Ne collisions with C, Al, Cu, Sn, Ta, and Pb targets at 600 Mev\\/nucleon using the the isospin-dependent Boltzmann-Langevin equation. We found that the production cross sections for fragments Z = 2 to 9 are qualitatively reproduced by the present calculations except for C target. In order to understand the effects

  11. Path forward for dosimetry cross sections

    SciTech Connect

    Griffin, P.J. [Sandia National Laboratories, Albuquerque, NM 87185-1146 (United States); Peters, C.D. [Sandia Staffing Alliance, Albuquerque, NM 87110 (United States)

    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)

  12. Evaluation methods for neutron cross section standards

    SciTech Connect

    Bhat, M.R.

    1980-01-01

    Methods used to evaluate the neutron cross section standards are reviewed and their relative merits, assessed. These include phase-shift analysis, R-matrix fit, and a number of other methods by Poenitz, Bhat, Kon'shin and the Bayesian or generalized least-squares procedures. The problems involved in adopting these methods for future cross section standards evaluations are considered, and the prospects for their use, discussed. 115 references, 5 figures, 3 tables.

  13. Rising Total Hadron-Hadron Cross Sections

    E-print Network

    Giorgio Giacomelli

    2007-12-06

    A historical summary is made on the measurements concerning the rising total hadron-hadron cross sections at high energies. The first part of this paper concerns the total cross section measurements performed at the Brookhaven, Serpukhov and Fermilab fixed target accelerators; then the measurements at the CERN Intersecting Storage Rings (ISR), and at the CERN and at the Tevatron Fermilab proton-antiproton colliders; finally the cosmic ray measurements at even higher energies. A short discussion on Conclusions and Perspectives follows.

  14. Predicting the Total Charm Cross Section

    SciTech Connect

    Vogt, R

    2008-05-29

    We discuss the energy dependence of the total charm cross section and some of its theoretical uncertainties including the quark mass, scale choice and the parton densities. Extracting the total charm cross section from data is a non-trivial task. To go from a finite number of measured D mesons in a particular decay channel to the total c{bar c} cross section one must: divide by the branching ratio for that channel; correct for the luminosity, {sigma}{sub D} = N{sub D}/Lt; extrapolate to full phase space from the finite detector acceptance; divide by two to get the pair cross section from the single Ds; and multiply by a correction factor to account for unmeasured charm hadrons. Early fixed-target data were at rather low p{sub T}, making the charm quark mass the most relevant scale. At proton and ion colliders, although the RHIC experiments can access the full pT range and thus the total cross section, the data reach rather high p{sub T}, p{sub T} >> m, making p{sub T} (m{sub T}) the most relevant scale. Here we focus on the total cross section calculation where the quark mass is the only relevant scale.

  15. Measurement of the W + single charm production cross section using soft electron tags

    E-print Network

    Fermilab

    Measurement of the W + single charm production cross section using soft electron tags with 4.3/fb a measurement of the production cross section of a W boson and a single charm quark, #Wc , using soft electron]. No correlation between the charge of the primary lepton (from the W decay) and the charge of the soft electron

  16. The data base of the standards and related cross sections after ENDF/B-VI

    SciTech Connect

    Poenitz, W.P. (Argonne National Lab., IL (United States)); Carlson, A.D. (National Inst. of Standards and Technology, Washington, DC (United States))

    1992-01-01

    A brief description is given of the procedure used in the global evaluation of the standards and other important cross sections for ENDF/B-VI. The results of the evaluation are compared with new or revised experimental data.

  17. Actinide cross section program at ORELA

    SciTech Connect

    Dabbs, J.W.T.

    1980-01-01

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

  18. 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.

  19. Inclusive parton cross sections in photoproduction and photon structure

    E-print Network

    Ahmed, T; Andrieu, B; Appuhn, R D; Arpagaus, M; Aïd, S; Babaev, A; Ban, Y; Baranov, P S; Barrelet, E; Bartel, Wulfrin; Barth, Monique; Bassler, U; Beck, H P; Behrend, H J; Belousov, A; Berger, C; Bergstein, H; Bernardi, G; Bernet, R; Bertrand-Coremans, G H; Besançon, M; Beyer, R; Biddulph, P; Bispham, P; Bizot, J C; Blobel, Volker; Borras, K; Botterweck, F; Boudry, V; Braemer, A; Brasse, F W; Braunschweig, W; Brisson, V; Bruncko, Dusan; Brune, C R; Buchholz, R; Buniatian, A Yu; Burke, S; Burton, M; Buschhorn, G W; Bán, J; Bähr, J; Büngener, L; Bürger, J; Büsser, F W; Campbell, A J; Carli, T; Charles, F; Charlet, M; Chernyshov, V; Clarke, D; Clegg, A B; Clerbaux, B; Colombo, M G; Contreras, J G; Cormack, C; Coughlan, J A; Courau, A; Coutures, C; Cozzika, G; Criegee, L; Cussans, D G; Cvach, J; Dagoret, S; Dainton, J B; Dau, W D; Daum, K; David, M; De Wolf, E A; Del Buono, L; Delcourt, B; Di Nezza, P; Dollfus, C; Dowell, John D; Dreis, H B; Droutskoi, A; Duboc, J; Duhm, H; Düllmann, D; Dünger, O; Ebert, J; Ebert, T R; Eckerlin, G; Efremenko, V; Egli, S; Eichenberger, S; Eichler, R; Eisele, Franz; Eisenhandler, Eric F; Ellison, R J; Elsen, E E; Erdmann, M; Erdmann, W; Erlichmann, H; Evrard, E; Favart, L; Fedotov, A; Feeken, D; Felst, R; Feltesse, Joel; Ferencei, J; Ferrarotto, F; Flamm, K; Fleischer, M; Flieser, M; Flügge, G; Fomenko, A; Fominykh, B A; Forbush, M; Formánek, J; Foster, J M; Franke, G; Fretwurst, E; Gabathuler, Erwin; Gabathuler, K; Gamerdinger, K; Garvey, J; Gayler, J; Gebauer, M; Gellrich, A; Genzel, H; Gerhards, R; Goerlach, U; Gogitidze, N; Goldberg, M; Goldner, D; González-Pineiro, B; Gorelov, I V; Goritchev, P A; Grab, C; Greenshaw, T J; Grindhammer, G; Gruber, A; Gruber, C; Grässler, Herbert; Grässler, R; Görlich, L; Haack, J; Haidt, Dieter; 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; Hladky, J; Hoeger, K C; Horisberger, R P; Hudgson, V L; Huet, Patrick; Hufnagel, H; Höppner, M; Hütte, M; Ibbotson, M; Itterbeck, H; Jabiol, M A; Jacholkowska, A; Jacobsson, C; Jaffré, M; Janoth, J; Jansen, T; Johnson, D P; Johnson, L; Jung, H; Jönsson, L B; Kalmus, Peter I P; Kant, D; Kaschowitz, R; Kasselmann, P; Kathage, U; Katzy, J M; Kaufmann, H H; Kazarian, S; Kenyon, Ian Richard; Kermiche, S; Keuker, C; Kiesling, C; Klein, M; Kleinwort, C; Knies, G; Ko, W; Kolanoski, H; Kole, F; Kolya, S D; Korbel, V; Korn, M; Kostka, P; Kotelnikov, S K; Krasny, M W; Krehbiel, H; Krämerkämper, T; Krücker, D; Krüger, U P; Krüner-Marquis, U; Kubenka, J P; Kuhlen, M; Kurca, T; Kurzhöfer, J; Kuznik, B; Köhler, T; Köhne, J H; Küster, H; Lacour, D; Lamarche, F; Lander, R; Landon, M P J; Lange, W; Lanius, P; Laporte, J F; Lebedev, A; Leverenz, C; Levonian, S; Ley, C; Lindner, A; Lindström, G; Link, J; Linsel, F; Lipinski, J; List, B; Lobo, G; Loch, P; Lohmander, H; Lomas, J W; Lubimov, V; López, G C; Lüke, D; Magnussen, N; Malinovskii, E I; Mani, S; Maracek, R; Marage, P; Marks, J; Marshall, R; Martens, J; Martin, R D; 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; Migliori, A; Mikocki, S; Milstead, D; Moreau, F; Morris, J V; Mroczko, E; Murín, P; Müller, G; Müller, K; Nagovitsin, V; Nahnhauer, R; Naroska, Beate; Naumann, T; Newman, P R; Newton, D; Neyret, D; Nguyen, H K; Nicholls, T C; Niebergall, F; Niebuhr, C B; Niedzballa, C; Nisius, R; Nowak, G; Noyes, G W; Nyberg-Werther, M; Oakden, M N; Oberlack, H; Obrock, U; Olsson, J E; Ozerov, D; Panaro, E; Panitch, A; Pascaud, C; Patel, G D; Peppel, E; Phillips, J P; Pichler, C; Pieuchot, A; Pitzl, D; Pope, G; Prell, S; Prosi, R; Pérez, E; Rabbertz, K; Raupach, F; Reimer, P; Reinshagen, S; Ribarics, P; Rick, Hartmut; Riech, V; Riedlberger, J; Riess, S; Rietz, M; Rizvi, E; Robertson, S M; Robmann, P; Roloff, H E; Roosen, R; Rosenbauer, K; Rostovtsev, A A; Rouse, F; Royon, C; Rusakov, S V; Rybicki, K; Rylko, R; Rädel, G; Rüter, K; Sahlmann, N; Salesch, S G; Sankey, D P C; Schacht, P; Schiek, S; Schleper, P; Schmidt, C; Schmidt, D; Schmidt, G; Schröder, V; Schuhmann, E; Schwab, B; Schwind, A; Schöning, A; Sefkow, F; Seidel, M; Sell, R; Semenov, A A; Shekelian, V I; Shevyakov, I; Shooshtari, H; Shtarkov, L N; Siegmon, G; Siewert, U; Sirois, Y; Skillicorn, Ian O; Smirnov, P; Smith, J R; Solochenko, V; Soloviev, Yu V; Spiekermann, J; Spielman, S; Spitzer, H; Starosta, R; Steenbock, M; Steffen, P; Steinberg, R; Stella, B; Stephens, K; Stier, J; Stiewe, J; Stolze, K; Strachota, J; Straumann, U; Struczinski, W; Stösslein, U; Sutton, J P; Sánchez, E; Tapprogge, Stefan; Thiebaux, C; Thompson, G; Truöl, P; Turnau, J; Tutas, J; Uelkes, P; Usik, A

    1995-01-01

    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\\le x_\\gamma \\le 1 at the average factorization scale 75 GeV^2.

  20. Angular differential cross section calculations for ion-helium collisions

    NASA Astrophysics Data System (ADS)

    Zapukhlyak, M.; Kirchner, T.

    2009-11-01

    We have calculated projectile angular-differential cross sections for various processes in ion-helium collisions. Key ingredients of our approach are the independent electron model, the two-center basis generator method for orbital propagation, and the eikonal approximation for the extraction of angular-differential scattering amplitudes. In general, we find good agreement with measurements; in some cases even for two-electron processes, although correlation effects are not taken into account.

  1. Inclusive parton cross sections in photoproduction and photon structure

    Microsoft Academic Search

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

    1995-01-01

    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 GeV2.

  2. SSC 50 mm dipole cross section

    SciTech Connect

    Gupta, R.C.; Kahn, S.A.; Morgan, G.H.

    1991-01-01

    In this paper we present the magnetic design of the two dimensional coil and iron cross section, referred to as DSX201/W6733, for the 50 mm aperture main ring dipole magnet for the Superconducting Super Collider (SSC). The computed values of the allowed field harmonics as a function of current, the quench performance predictions, the stored energy calculations, the effect of random errors on the coil placement and the Lorentz forces on the coil will be presented. The yoke has been optimized to reduce iron saturation effects on the field harmonics. We shall present the summary of this design which will include the expected overall performance of this cross section. Prototypes of these dipoles are being built at the Brookhaven National Laboratory (BNL) and at the Fermi National Accelerator Laboratory (FNAL). There are slight differences between the cross sections at the two laboratories. 7 refs., 6 figs., 11 tabs.

  3. 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.

  4. Revised cross section for RHIC dipole magnets

    SciTech Connect

    Thompson, P.A.; Gupta, R.C.; Kahn, S.A.; Hahn, H.; Morgan, G.H.; Wanderer, P.J.; Willen, E.

    1991-01-01

    Using the experience gained in designing and building Relativistic Heavy Ion Collider (RHIC) dipole prototype magnets an improved cross section has been developed. Significant features of this design include the use of only three wedges for field shaping and wedge cross sections which are sectors of an annulus. To aid in the understanding of the actual magnets, one has been sectioned, and detailed mechanical and photographic measurements made of the wire positions. The comparison of these measurements with the magnetic field measurements will is presented. 2 refs, 3 figs., 2 tabs.

  5. Electroweak Cross-sections and Widths

    SciTech Connect

    Robson, Aidan; /Glasgow U.

    2008-10-01

    The status of W and Z cross-section and width measurements from the CDF and D0 experiments is reviewed. Recent results that are discussed: the cross-section for Z production times the branching ratio to tau pairs, the rapidity and transverse momentum distributions of Z production in the electron channel, and the direct measurements of the W width and the Z invisible width; the latter from an analysis of events with large missing transverse energy and one or more energetic jets.

  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. Upscattering Cross Sections for Ultra Cold Neutrons from Gases

    NASA Astrophysics Data System (ADS)

    Seestrom, Susan J.; UCN? Collaboration

    2014-09-01

    The scattering of ultracold neutrons (UCNs) to energies above the escape potential of a trap is called upscattering. Upscattering due to interaction with residual gases is a potential loss mechanism for UCNs stored in a trap that can impact the extracted neutron lifetime. We have developed a method for measuring the cross sections for UCN upscattering from gases stored in a small measurement cell. Upscattered neutrons are measured directly in a 3He ionization chamber and transmitted UCN strike a 10B-coated surface at the edges of the measurement cell. The transmitted UCNs are then counted with a HPGe gamma-ray detector that counts 478 keV ?-rays from the 10B(n , ??) 7Li reaction. The analysis was guided by Monte Carlo descriptions of the LANL UCN source output. We will present cross sections measured for various noble and polyatomic gases, compare these results to calculated cross sections based on models of gas scattering kernels, and use these to estimate the impact of gas upscattering on the measurement of the neutron lifetime.

  8. Neutron scattering lengths and cross sections

    Microsoft Academic Search

    Varley F. Sears

    1992-01-01

    The application of thermal neutron scattering to the study of the structure and dynamics of condensed matter requires a knowledge of the scattering lengths and the corresponding scattering and absorption cross sections of the elements. Ln some cases, values for the individual isotopes are needed as well. This information is required to obtain an absolute normalization ofthe scatteredneutron distributions, tocalculate

  9. UV absorption cross sections for SO3

    Microsoft Academic Search

    James B. Burkholder; Stuart McKeen

    1997-01-01

    Room temperature gas phase absorption cross sections for SO3 have been measured over the wavelength range 195 to 330 nm using a diode array spectrometer. The SO3 spectrum is continuous with weak diffuse vibrational band structure in the 225 to 295 nm region. Atmospheric photolysis rate calculations show that photolysis of SO3 in the 190 to 230 nm actinic window

  10. Absolute photoionization cross sections of atomic oxygen

    NASA Astrophysics Data System (ADS)

    Berkowitz, J.

    1997-02-01

    Conflicting calibrations of the absolute photoionization cross sections of atomic oxygen in the vacuum and extreme ultraviolet are tested by a sum-rule analysis. It is shown that the scaling factor obtained by Samson and Pareek results in much closer adherence to three sum rules.

  11. ZIRCONIUM CROSS SECTIONS FOR REACTOR CALCULATIONS

    Microsoft Academic Search

    W. Skolnik; N. C. Francis

    1959-01-01

    It is shown that the use of realistic Zr cross sections in the ; calculations of the group constants, yields values or k\\/sub eff\\/ in substantial ; agreement with the Goldsmith predictions and experiments. A companison of ages ; of Zr-Hâ0 mixtures was made between calculated and experimental results. A ; number of clean critical experiments were calcillated in a

  12. A Pebble Bed Reactor cross section methodology

    Microsoft Academic Search

    Nathanael H. Hudson; Abderrafi. M. Ougouag; Farzad Rahnema; Hans Gougar

    2009-01-01

    A method is presented for the evaluation of microscopic cross sections for the Pebble Bed Reactor (PBR) neutron diffusion computational models during convergence to an equilibrium (asymptotic) fuel cycle. This method considers the isotopics within a core spectral zone and the leakages from such a zone as they arise during reactor operation. The randomness of the spatial distribution of fuel

  13. Radiation pressure cross section for fluffy aggregates.

    NASA Astrophysics Data System (ADS)

    Kimura, H.; Mann, I.

    1998-09-01

    The authors apply the discrete dipole approximation (DDA) to estimate the radiation pressure cross section for fluffy aggregates by computing the asymmetry parameter and the cross sections for extinction and scattering. The ballistic particle-cluster aggregate and the ballistic cluster-cluster aggregate consisting of either dielectric or absorbing material are considered to represent naturally existing aggregates. The authors show that the asymmetry parameter perpendicular to the direction of wave propagation is maximized where the wavelength is comparable to the aggregate size, which may be characterized by the area-equivalent radius or the radius of gyration rather than the volume-equivalent radius. The asymmetry parameter for the aggregate depends on the morphology of the particle, but not on the constituent material. Therefore, the dependence of the radiation pressure cross section on the material composition arises mainly from that of the extinction and scattering cross sections, in other words, the single-scattering albedo. The authors find that aggregates consisting of high-albedo material show a large deviation of radiation pressure from the direction of incident radiation. When the aggregates are illuminated by blackbody radiation, the deviation of the radiation pressure increases with increasing temperature of the blackbody.

  14. 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.

  15. LSP-Nucleus Elastic Scattering Cross Sections

    E-print Network

    J. D. Vergados; T. S. Kosmas

    1997-01-02

    We calculate LSP-nucleus elastic scattering cross sections using some representative input in the restricted SUSY parameter space. The coherent matrix elements are computed throughout the periodic table while the spin matrix elements for the proposed $^{207}Pb$ target which has a rather simple nuclear structure. The results are compared to those given from other cold dark matter detection targets.

  16. Calculating Cross Sections of Composite Interstellar Grains

    E-print Network

    Nikolai V. Voshchinnikov; John S. Mathis

    1999-08-21

    Interstellar grains may be composite collections of particles of distinct materials, including voids, agglomerated together. We determine the various optical cross sections of such composite grains, given the optical properties of each constituent, using an approximate model of the composite grain. We assume it consists of many concentric spherical layers of the various materials, each with a specified volume fraction. In such a case the usual Mie theory can be generalized and the extinction, scattering, and other cross sections determined exactly. We find that the ordering of the materials in the layering makes some difference to the derived cross sections, but averaging over the various permutations of the order of the materials provides rapid convergence as the number of shells (each of which is filled by all of the materials proportionately to their volume fractions) is increased. Three shells, each with one layer of a particular constituent material, give a very satisfactory estimate of the average cross section produced by larger numbers of shells. We give the formulae for the Rayleigh limit (small size parameter) for multi-layered spheres and use it to propose an ``Effective Medium Theory'' (EMT), in which an average optical constant is taken to represent the ensemble of materials. Multi-layered models are used to compare the accuracies of several EMTs already in the literature.

  17. Calculating Cross Sections of Composite Interstellar Grains

    Microsoft Academic Search

    Nikolai V. Voshchinnikov; John S. Mathis

    1999-01-01

    Interstellar grains may be composite collections of particles of distinct materials, including voids agglomerated together. We determine the various optical cross sections of such composite grains, given the optical properties of each constituent, using an approximate model of the composite grain. We assume it consists of many concentric spherical layers of the various materials, each with a specified volume fraction.

  18. KLOE results on hadronic cross section

    NASA Astrophysics Data System (ADS)

    Mandaglio, Giuseppe; Ambrosino, F.; Antonelli, A.; Antonelli, M.; Archilli, F.; Balwierz, I.; Bencivenni, G.; Bini, C.; Bloise, C; . Bocchetta, S.; Bossi, F.; Branchini, P.; Capon, G.; Capussela, T.; Ceradini, F.; Ciambrone, P.; Czerwi?ski, E.; De Lucia, E.; De Santis, A.; De Simone, P.; De Zorzi, G.; Denig, A.; Di Domenico, A.; Di Donato, C.; Di Micco, B.; Dreucci, M.; Felici, G.; Fiore, S.; Franzini, P.; Gatti, C.; Gauzzi, P.; Giovannella, S.; Graziani, E.; Jacewicz, M.; Kluge, W.; Lee-Franzini, J.; Lukin, P.; Martemianov, M.; Martini, M.; Massarotti, P.; Meola, S.; Miscetti, S.; Morello, G.; Moulson, M.; Müller, S; . Napolitano, M.; Nguyen, F.; Palutan, M.; Passeri, A.; Patera, V.; Prado Longhi, I.; Santangelo, P.; Sciascia, B.; Silarski, M.; Spadaro, T.; Taccini, C.; Tortora, L.; Venanzoni, G.; Versaci, R.; Xu, G.; Zdebik, J.; Babusci, D.; Badoni, D.; Bocci, V.; Budano, A.; Bulychjev, S. A; .; Caldeira Balkeståhl, L.; Campana, P.; Dané, E.; De Robertis, G.; Domenici, D.; Erriquez, O.; Fanizzi, G.; Giardina, G.; Gonnella, F.; Happacher, F.; Höistad, B.; Iafolla, L.; Iarocci, E.; Johansson, T.; Kowalewska, A.; Kulikov, V.; Kupsc, A.; Loddo, F.; Mandaglio, G.; Mascolo, M.; Matsyuk, M.; Messi, R.; Moricciani, D.; Ranieri, A.; Redmer, C. F.; Sarra, I.; Schioppa, M.; Sciubba, A.; Wi?licki, W.; Wolke, M.; KLOE/KLOE-2 Collaborations

    2012-03-01

    The KLOE experiment at the phi - factory DA?NE is the first to have exploited Initial State Radiation (ISR) to precisely determine the e+e- ? ?+?-(?) cross section below 1 GeV, representing the 70% of the leading order contribution to the muon anomaly. The leading order contribution ahlo? is presently the main source of uncertainty in the theoretical evaluation of the muon anomaly, and it can be evaluated by dispersion integral using the experimental measurement of hadronic cross section. A persistent discrepancy of about 3 ? between standard model (SM) prediction and experimental measurements of the muon anomalous magnetic moment has been up to now observed. The KLOE collaboration published two measurements of the ?+?- cross section with the photon in the initial state emitted at small polar angle in Phys. Lett. B vol. 606 pg. 12 and vol. 670 pg. 285, and an independent measurement with the photon emitted at large polar angle in Phys. Lett. B vol. 700 pg. 102. These measurements were normalized to the DA?NE luminosity. Recently, a new analysis deriving the pion form factor directly from measuring the bin-by-bin ?+?? and ?+?? final states ratio has been performed. In this paper, the preliminary results of this new measurement and the comparison to the previous published ones, the impact on the evaluation of the hadronic contribution to the muon anomaly, the preliminary ?+?? cross section measurement and the comparison with the PHOKHARA-MC prediction are presented.

  19. 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.

  20. Neutron cross section standards and flux determinations above thermal energies

    Microsoft Academic Search

    1975-01-01

    The recent worldwide advances in nuclear technology, particularly fast fission and fusion reactors, have revealed the need for accurate neutron reaction cross sections for the design of these systems. The accuracies of these cross sections are generally limited by the standard cross sections relative to which they are measured. With the exception of the hydrogen scattering cross section, there have

  1. Representation of absorption cross sections in information system W@DIS

    NASA Astrophysics Data System (ADS)

    Voronina, Yu.; Lavrentiev, N.; Privezentsev, A.; Fazliev, A.; Firsov, K.

    2014-11-01

    Our research into generation of a set of absorption cross sections of atmospheric molecules is reviewed briefly. Particular emphasis is placed on a description of a software toolkit for building information objects that characterize molecules and weakly bound molecular complexes, an application that provides the import and export of the absorption cross sections and representation of metadata and ontolology of information resources collected in a set.

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

    SciTech Connect

    Laptev, Alexander B [Los Alamos National Laboratory; Haight, Robert C [Los Alamos National Laboratory; Tovesson, Fredrik [Los Alamos National Laboratory; Arndt, Richard A [GWU; Briscoe, William J [GWU; Paris, Mark W [GWU; Strakovsky, Igor I [GWU; Workman, Ron L [GWU

    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.

  3. 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. [Los Alamos National Laboratory, Los Alamos NM 87545 (United States); Arndt, R. A.; Briscoe, W. J.; Paris, M. W.; Strakovsky, I. I.; Workman, R. L. [George Washington University, Washington DC 20052 (United States)

    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.

  4. 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).

  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. Electron capture cross sections for stellar nucleosynthesis

    E-print Network

    Giannaka, P G

    2015-01-01

    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.

  7. The calculation of rainbow scattering cross sections

    Microsoft Academic Search

    R. J. Munn; Francis J. Smith

    1966-01-01

    A method is described for calculating low resolution differential cross sections near the rainbow angle. It is used to calculate a table of the positions of the principal maxima and minima in the rainbow structure for a 6–12 potential for different rainbow angles and different values of the de Boer parameter, ?*, between 0·1 and 0·01. A comparison with similar

  8. Inclusive jet cross section measurement at CDF

    SciTech Connect

    Pagliarone, C. [Universita di Torino and INFN, Trieste (Italy)

    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.

  9. Electron excitation cross sections for Si XII

    Microsoft Academic Search

    S. Kastner; C. Wade; T. S. Smith; M. Blaha

    1972-01-01

    Excitation cross sections are calculated for Si XII by the coulomb-Born method, using numerical Hartree-Fock radial functions. The transitions considered are 2s-np, ns-n'd, 2p-nd and 3s-np. Reasonable agreement with the general results of Bely and Petrini is obtained, but an appreciable difference occurs for 2s-7p. The effect of including higher multipoles in the coulomb-Born method is illustrated. For comparison, the

  10. Neutron Activation Cross Section of Technetium98

    Microsoft Academic Search

    Edward Anders

    1958-01-01

    The cross section for the reaction Tc98(n, gamma)Tc99m was determined by thermal neutron irradiation of a cyclotron-produced sample containing Tc95, Tc97m, Tc97g, Tc98, and Tc99. The degree of selectivity and background reduction required to permit an accurate measurement of the Tc98 content, 2.68+\\/-0.54 disintegrations per minute, was attained by means of beta-(740-Kev gamma) coincidence counting. At a thermal flux of

  11. 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.

  12. ACTL: evaluated neutron activation cross section library-evaluation techniques and reaction index. [Tables, 10¹° to 20 MeV

    Microsoft Academic Search

    M. A. Gardner; R. J. Howerton

    1978-01-01

    A library of evaluated neutron-induced activation cross sections (ACTL) was compiled. The library covers incident neutron energies from 10¹° to 20 MeV. General descriptions of the evaluation methods and an index to the evaluated cross sections are presented. 21 references.

  13. Fission Cross Sections of Uranium, Thorium, Bismuth, Lead, and Gold Induced by 58- to 100MeV Alpha Particles

    Microsoft Academic Search

    J. Ralarosy; M. Debeauvais; G. Remy; J. Tripier; R. Stein; D. Huss

    1973-01-01

    The results presented in this paper have been obtained from experiments using a makrofol (a polycarbonate) detector. After a brief description of the experimental technique, values of measured cross sections are given. These values are discussed in comparison with some known results about spallation reactions, referring to reaction cross sections theoretically calculated from optical models.

  14. Theoretical and empirical analysis of the average cross-sectional areas of breakup fragments

    NASA Astrophysics Data System (ADS)

    Hanada, T.; Liou, J.-C.

    2011-05-01

    This paper compares two different approaches to calculate the average cross-sectional area of breakup fragments. The first one is described in the NASA standard breakup model 1998 revision. This approach visually classifies fragments into several shapes, and then applies formulae developed for each shape to calculate the average cross-sectional area. The second approach was developed jointly by the Kyushu University and the NASA Orbital Debris Program Office. This new approach automatically classifies fragments into plate- or irregular-shapes based on their aspect ratio and thickness, and then applies formulae developed for each shape to calculate the average cross-sectional area. The comparison between the two approaches is demonstrated in the area-to-mass ratio ( A/m) distribution of fragments from two microsatellite impact experiments completed in early 2008. A major difference between the two approaches comes from the calculation of the average cross-sectional area of plates. In order to determine which of the two approaches provides a better description of the actual A/m distribution of breakup fragments, a theoretical analysis in the calculation of the average cross-sectional area of an ideal plate is conducted. This paper also investigates the average cross-sectional area of multi-layer insulation fragments. The average cross-sectional area of 214 multi-layer insulation fragments was measured by a planimeter, and then the data were used to benchmark the average cross-sectional areas estimated by the two approaches. The uncertainty in the calculation of the average cross-sectional area with the two approaches is also discussed in terms of size and thickness.

  15. NASA-Lewis experiences with multigroup cross sections and shielding calculations.

    NASA Technical Reports Server (NTRS)

    Lahti, G. P.

    1972-01-01

    Description of the nuclear reactor shield analysis procedures employed at NASA-Lewis Research Center. Emphasis is placed on the generation, use, and testing of multigroup cross-section data. Although coupled neutron and gamma ray cross-section sets are useful in two-dimensional Sn transport calculations, much insight has been gained from examination of uncoupled calculations. These have led to experimental and analytic studies of areas deemed to be of first-order importance to reactor shield calculations. A discussion is given of problems encountered in using multigroup cross sections in the resolved resonance energy range. The addition to ENDF files of calculated and/or measured neutron-energy-dependent capture gamma ray spectra for shielding calculations is questioned for the resonance region. Anomalies inherent in two-dimensional Sn transport calculations which may overwhelm any cross-section discrepancies are illustrated.

  16. Statistical treatment of detection cross-section uncertainties in the analysis of solar neutrino data

    E-print Network

    M. V. Garzelli; C. Giunti

    2000-06-13

    We propose a modification to the standard statistical treatment of the detection cross-section uncertainties in the analysis of solar neutrino data. We argue that the uncertainties of the energy-averaged cross sections of the different neutrino fluxes in the same experiment should be treated as correlated. We show that the resulting allowed regions for the neutrino oscillation parameters are significantly larger than the ones obtained with uncorrelated uncertainties.

  17. NIST XCOM: Photon Cross Sections Database

    NSDL National Science Digital Library

    This web program, funded in part by the National Institute of Standards and Technology (U.S.) is used to calculate photon cross sections for scattering, photoelectric absorption and pair production, as well as total attenuation coefficients, in any element, compound or mixture, at energies from 1 keV to 100 GeV. The contents section of the site contains an introduction, database for elements, interpolation and combination, instructions on how to run the XCOM program, and references. The site allows you to download a copy of XCOM (v. 3.1) for personal use.

  18. Neutron activation cross sections on lead isotopes

    Microsoft Academic Search

    V. Semkova; P. Reimer; T. Altzitzoglou; A. J. M. Plompen; C. Quetel; S. Sudar; J. Vogl; A. J. Koning; S. M. Qaim; D. L. Smith

    2009-01-01

    The cross sections for the reactions ²°Pb(n,n{sup '})²°Pb{sup m}, ²°Pb(n,2n)²°³Pb, ²°Pb(n,2n)²°³Pb{sup m1}, ²°Pb(n,3n)²°²Pb{sup m}, ²°Pb(n,3n)²°Pb{sup m}, ²°Pb(n,)²°³Hg, and ²°Pb(n,p)²°Tl were determined at the IRMM van de Graaff laboratory in the neutron energy range from 14 to 21 MeV. Both natural and enriched samples were irradiated with neutrons produced via the ³H(d,n)He reaction. The induced activities were determined by gamma-ray spectrometry

  19. Dielectronic recombination cross sections of neonlike xenon

    NASA Astrophysics Data System (ADS)

    Dewitt, D. R.; Schneider, D.; Chen, M. H.; Clark, M. W.; McDonald, J. W.; Schneider, M. B.

    1992-03-01

    High-resolution measurements of dielectronic recombination cross sections for neonlike xenon (Xe44+) are presented. The experimental method consists 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. Low beam currents are used to obtain an energy resolution of 16 eV FWHM. Reductions in the number of initial ions of more than 3 orders of magnitude are observed as the strongest resonances are scanned. The relative contributions of the LMM, LMN, LMO, LMP, and LMQ groups of resonances are compared to theoretical calculations. The agreement with theory is excellent.

  20. 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.

  1. Statistics of cross sections of Voronoi tessellations

    NASA Astrophysics Data System (ADS)

    Ferraro, M.; Zaninetti, L.

    2011-10-01

    In this paper, we investigate relationships between the volumes of cells of three-dimensional Voronoi tessellations and the lengths and areas of sections obtained by intersecting the tessellation with a randomly oriented plane. Here, in order to obtain analytical results, Voronoi cells are approximated to spheres. First, the probability density function for the lengths of the radii of the sections is derived and it is shown that it is related to the Meijer G function; its properties are discussed and comparisons are made with the numerical results. Next, the probability density function for the areas of cross sections is computed and compared with the results of numerical simulations.

  2. 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 and analysis. The reactor diameter was 23 cm and the bed height was maintained at 22 cm for these tests. More

  3. 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...

  4. Low-energy electron elastic scattering cross sections for excited Au and Pt atoms

    NASA Astrophysics Data System (ADS)

    Felfli, Zineb; Eure, Amanda R.; Msezane, Alfred Z.; Sokolovski, Dmitri

    2010-05-01

    Electron elastic total cross sections (TCSs) and differential cross sections (DCSs) in both impact energy and scattering angle for the excited Au and Pt atoms are calculated in the electron impact energy range 0 ? E ? 4.0 eV. The cross sections are found to be characterized by very sharp long-lived resonances whose positions are identified with the binding energies of the excited anions formed during the collisions. The recent novel Regge-pole methodology wherein is embedded through the Mulholland formula the electron-electron correlations is used together with a Thomas-Fermi type potential incorporating the crucial core-polarization interaction for the calculations of the TCSs. The DCSs are evaluated using a partial wave expansion. The Ramsauer-Townsend minima, the shape resonances and the binding energies of the excited Au - and Pt - anions are extracted from the cross sections, while the critical minima are determined from the DCSs.

  5. Fast Neutron Activation Cross Section of Au197

    Microsoft Academic Search

    S. A. Cox

    1961-01-01

    The neutron activation cross section of gold was measured in the neutron range from 30-1500 kev. The absolute value of the cross section was based on the U235 fast fission cross section which was used for absolute neutron flux measurements from 200-1500 kev. For measurements below 200 kev, the B10(n, alpha) cross section was used for monitoring the neutron flux.

  6. 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).

  7. Analytic Cross Sections for Substructure Lensing

    E-print Network

    Charles R. Keeton

    2002-10-28

    The magnifications of the images in a strong gravitational lens system are sensitive to small mass clumps in the lens potential; this effect has been used to infer the amount of substructure in galaxy dark matter halos. I study the theory of substructure lensing to identify important general features, and to compute analytic cross sections that will facilitate further theoretical studies. I show that the problem of a clump anywhere along the line of sight to a lens can be mapped onto an equivalent problem of a clump in a simple convergence and shear field; clumps at arbitrary redshifts are therefore not hard to handle in calculations. For clumps modeled as singular isothermal spheres (SIS), I derive simple analytic estimates of the cross section for magnification perturbations of a given strength. The results yield two interesting conceptual points. First, lensed images with positive parity are always made brighter by SIS clumps; images with negative parity can be brightened but are much more likely to be dimmed. Second, the clumps need not lie within the lens galaxy; they can be moved in redshift by several tenths and still have a significant lensing effect. Isolated small halos are expected to be common in hierarchical structure formation models, but it is not yet known whether they are abundant enough compared with clumps inside lens galaxies to affect the interpretation of substructure lensing.

  8. 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.

  9. 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…

  10. Making a Geologic Cross Section Name _____________________________ Geology 100 Harbor Section

    E-print Network

    Harbor, David

    of cross section A for help) 2. What symbols represent these formations and in what geologic time periodsp. 1 Making a Geologic Cross Section Name _____________________________ Geology 100 ­ Harbor Section Your task is to complete a cross section of geologic structures from a geologic map. Please do

  11. ANALYTIC EXPRESSIONS FOR AEROSOL LIGHT-SCATTERING CROSS SECTION

    E-print Network

    ANALYTIC EXPRESSIONS FOR AEROSOL LIGHT-SCATTERING CROSS SECTION Ernie R. Lewis For Presentation Upton, NY 11973-5000 www.bnl.gov ABSTRACT The light-scattering cross section is an intrinsic property consisting of spherical particles of uniform composition, the light-scattering cross section can

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

    Microsoft Academic Search

    1990-01-01

    The design and improvement of nuclear reactors require detailed neutronics calculations. These calculations depend on comprehensive libraries of evaluated nuclear cross sections. Most of the cross sections that form the data base for these evaluations have been measured relative to neutron cross-section standards. The use of these standards can often simplify the measurement process by eliminating the need for a

  13. Effects of charge exchange cross section on ENAs

    Microsoft Academic Search

    K. Scherer; H. Fichtner

    2006-01-01

    A crucial point in interpreting the data of the upcoming IBEX mission is a good knowledge of the charge exchange cross section between shocked solar wind protons and interstellar hydrogen There exists at least four formulae which describe the data for the respective cross section We will discuss the effects of the different cross sections for the ENA flux at

  14. Electron-hydrogen cross section computation for astrophysical applications

    NASA Astrophysics Data System (ADS)

    Benda, Jakub; Houfek, Karel

    2012-06-01

    Our contribution focuses on the electron-hydrogen scattering and is intended as an extension of available atomic databases (e.g [1]) used by the astronomers and stellar/solar physicists. These databases often lack required precision and sometimes even major resonances, which are essential for correct transition rates extraction and thus for the description of astrophysical phenomena. Our aim is to obtain a controlled approximation of scattering cross section energy dependence for all relevant energies and (de)excitational transitions. The poster summarises results computed by freely available (e.g. [2], [3]) computer codes and compares them with our original results. Low energy cross sections - up to this time a domain of R-matrix packages - have been recomputed using exterior complex scaling implemented in B-splines (see [4]), whereas higher energies using different types of Born approximation.[4pt] [1] The Aladdin database at http://www-amdis.iaea.org/ALADDIN/[0pt] [2] UK RmaX at http://amdpp.phys.strath.ac.uk/UK$RmaX/[0pt] [3] Scott et al., Comp. Phys. Comm. 180 (2009) 2424-2449.[0pt] [4] McCurdy, Rescigno, J. Phys. B: At. Mol. Opt. Phys. 37 (2004) 917-936.

  15. Graphs of the cross sections in the Alternate Monte Carlo Cross Section library at the Los Alamos Scientific Laboratory

    SciTech Connect

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

    1980-06-01

    Graphs of all neutron cross sections and photon production cross sections on the Alternate Monte Carlo Cross Section (AMCCS) library have been plotted along with local neutron heating numbers. The values of ..nu..-bar, the average number of neutrons per fission, are also plotted for appropriate isotopes.

  16. 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.

  17. Experiment to measure total cross sections, differential cross sections and polarization effects in pp elastic scattering at RHIC

    SciTech Connect

    Guryn, W.

    1998-02-01

    The authors are describing an experiment to study proton-proton (pp) elastic scattering experiment at the Relativistic Heavy Ion Collider (RHIC). Using both polarized and unpolarized beams, the experiment will study pp elastic scattering from {radical}s = 50 GeV to {radical}s = 500 GeV in two kinematical regions. In the Coulomb Nuclear Interference (CNI) region, 0.0005 < {vert_bar}t{vert_bar} < 0.12 (GeV/c){sup 2}, they will measure and study the s dependence of the total and elastic cross sections, {sigma}{sub tot} and {sigma}{sub el}; the ratio of the real to the imaginary part of the forward elastic scattering amplitude, {rho}; and the nuclear slope parameter of the pp elastic scattering, b. In the medium {vert_bar}t{vert_bar}-region, {vert_bar}t{vert_bar} < 1.5 (GeV/c){sup 2}, they plan to study the evolution of the dip structure with s, as observed at ISR in the differential elastic cross section, d{sigma}{sub el}/dt, and the s and {vert_bar}t{vert_bar} dependence of b. With the polarized beams the following can be measured: the difference in the total cross sections as function of initial transverse spin states {Delta}{sigma}{sub T}, the analyzing power, A{sub N}, and the transverse spin correlation parameter A{sub NN}. The behavior of the analyzing power A{sub N} at RHIC energies in the dip region of d{sigma}{sub el}/dt, where a pronounced structure was found at fixed-target experiments will be studied. The relation of pp elastic scattering to the beam polarization measurement at RHIC is also discussed.

  18. Collision cross sections for structural proteomics.

    PubMed

    Marklund, Erik G; Degiacomi, Matteo T; Robinson, Carol V; Baldwin, Andrew J; Benesch, Justin L P

    2015-04-01

    Ion mobility mass spectrometry (IM-MS) allows the structural interrogation of biomolecules by reporting their collision cross sections (CCSs). The major bottleneck for exploiting IM-MS in structural proteomics lies in the lack of speed at which structures and models can be related to experimental data. Here we present IMPACT (Ion Mobility Projection Approximation Calculation Tool), which overcomes these twin challenges, providing accurate CCSs up to 10(6) times faster than alternative methods. This allows us to assess the CCS space presented by the entire structural proteome, interrogate ensembles of protein conformers, and monitor molecular dynamics trajectories. Our data demonstrate that the CCS is a highly informative parameter and that IM-MS is of considerable practical value to structural biologists. PMID:25800554

  19. Neutron activation cross sections on lead isotopes

    Microsoft Academic Search

    V. Semkova; P. Reimer; T. Altzitzoglou; A. J. M. Plompen; C. Quétel; S. Sudár; J. Vogl; A. J. Koning; S. M. Qaim; D. L. Smith

    2009-01-01

    The cross sections for the reactions Pb204(n,n'gamma)Pb204m, Pb204(n,2n)Pb203, Pb204(n,2n)Pb203m1, Pb204(n,3n)Pb202m, Pb206(n,3n)Pb204m, Pb206(n,alpha)Hg203, and Pb208(n,p)Tl208 were determined at the IRMM van de Graaff laboratory in the neutron energy range from 14 to 21 MeV. Both natural and enriched samples were irradiated with neutrons produced via the H3(d,n)He4 reaction. The induced activities were determined by gamma-ray spectrometry using a HPGe detector in

  20. Neutron activation cross sections for zirconium isotopes

    Microsoft Academic Search

    V. Semkova; E. Bauge; A. J. M. Plompen; D. L. Smith

    2010-01-01

    New experimental cross sections are presented for Zr90(n,?)87mSr, Zr90(n,x)89mY, Zr90(n,p)90mY, Zr90(n,2n)89Zr, Zr90(n,2n)89mZr, Zr91(n,n?)87mSr, Zr91(n,x)90mY, Zr91(n,p)91mY, Zr92(n,x)91mY, Zr92(n,p)92Y, Zr94(n,?)91Sr, Zr94(n,x)93Y and Zr94(n,p)94Y reactions. These have been obtained with the activation technique using gamma-ray spectrometry and irradiations at the IRMM Van de Graaff laboratory. The new data were obtained in the energy range from 14 to 21 MeV. In nearly all cases

  1. 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.

  2. Dielectronic recombination cross sections of neonlike xenon

    SciTech Connect

    DeWitt, D.R.; Schneider, D.; Chen, M.H.; Clark, M.W.; McDonald, J.W.; Schneider, M.B. (Lawrence Livermore National Laboratory, University of California, Livermore, California 94550 (United States))

    1992-03-16

    High-resolution measurements of dielectronic recombination cross sections for neonlike xenon (Xe{sup 44+}) are presented. The experimental method consists 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. Low beam currents are used to obtain an energy resolution of 16 eV FWHM. Reductions in the number of initial ions of more than 3 orders of magnitude are observed as the strongest resonances are scanned. The relative contributions of the {ital LMM}, {ital LMN}, {ital LMO}, {ital LMP}, and {ital LMQ} groups of resonances are compared to theoretical calculations. The agreement with theory is excellent.

  3. Angle-averaged Compton cross sections

    SciTech Connect

    Nickel, G.H.

    1983-01-01

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

  4. Status of high energy neutron cross sections

    SciTech Connect

    Browne, J.C.; Lisowski, P.W.

    1980-01-01

    Review is presented of the current status of neutron-induced reactions of interest to the fusion community in the 10- to 50-MeV neutron energy range. Although there has been significant activity in this area since the 1977 BNL Symposium on Neutron Cross Sections from 10 to 40 MeV, this review concludes that there are many areas which require more experimentation to obtain the requested accuracy. Examples of various neutron data obtained since 1977 are presented and compared to determine the extent of agreement. An attempt is made to determine what the prospects are for satisfying the fusion data needs defined by the US DOE based upon progress to date.

  5. Diffractive DIS Cross Sections and Parton Distributions

    E-print Network

    F. -P. Schilling

    2006-08-31

    Highlights are presented mainly from two recent measurements of the diffractive Deep Inelastic Scattering cross section at HERA. In the first, the process $ep\\to eXp$ is studied by tagging the leading final state proton. In the second, events of this type are selected by requiring a large rapidity gap devoid of hadronic activity in the proton direction. The two measurements are compared in detail and the kinematic dependences are interpreted within the framework of a factorisable diffractive exchange. Diffractive parton distributions are determined from a next-to-leading order QCD analysis of the large rapidity gap data, which can be applied to the prediction of diffractive processes, also at the TEVATRON and the LHC.

  6. CCKT Calculation of e-H Total Cross Sections

    NASA Technical Reports Server (NTRS)

    Bhatia, Aaron K.; Schneider, B. I.; Temkin, A.; Fisher, Richard R. (Technical Monitor)

    2002-01-01

    We are in the process of carrying out calculations of e-H total cross sections using the 'complex-correlation Kohn-T' (CCKT) method. In a later paper, we described the methodology more completely, but confined calculations to the elastic scattering region, with definitive, precision results for S-wave phase shifts. Here we extend the calculations to the (low) continuum (1 much less than k(exp 2) much less than 3) using a Green's function formulation. This avoids having to solve integro-differential equations; rather we evaluate indefinite integrals involving appropriate Green's functions and the (complex) optical potential to find the scattering function u(r). From the asymptotic form of u(r) we extract a T(sub L) which is a complex number. From T(sub L), elastic sigma(sub L)(elastic) = 4pi(2L+1)((absolute value of T(sub L))(exp 2)), and total sigma (sub L)(total) = 4pi/k(2L+1)Im(T(sub L)) cross sections follow.

  7. Cross-section uncertainty propagation in the multigroup slowing-down equations using probability table formalism

    SciTech Connect

    Diop, Cheikh M.; Coste-Delclaux, Mireille; Lahaye, Sebastien [CEA Saclay, Serv Etud Reacteurs et Math Appl, DEN DANS DM2S, Commissariat Energie Atom et Energies Alternat, F-91191 Gif Sur Yvette, (France)

    2012-01-15

    In the frame of neutral-particle (neutron, gamma) transport, the uncertainty propagation calculation regarding the uncertainties on cross sections is often carried out without explicitly taking into account their probabilistic distribution. We investigate a new uncertainty propagation formalism where the cross-section uncertainty distributions are represented by probability tables. This technical note develops this approach for the steady-state slowing-down equation without up-scattering and in an infinite medium. This work is based on a deterministic multiband formalism that takes into account multilevel probability tables for cross sections. The first level represents the variation of cross sections versus lethargy (or energy) in each group of the multigroup lethargy mesh and thus corresponds to the classical cross-section probability tables. The higher levels represent the uncertainties on each step of the first-level cross-section probability table. This method is validated against a Monte Carlo calculation in a case of neutron slowing down in a {sup 238}U-hydrogen homogeneous mixture, showing fully consistent numerical results. The main interest of the deterministic multilevel multiband formalism is that it gives not only the mean value and the variance but also a probabilistic distribution of the fluxes. In the near future, we plan to investigate more deeply the robustness of this new approach in relation to high values of cross-section uncertainties and to introduce cross-section uncertainty correlations as well. Meanwhile, the promise of this work is its extension to the general transport steady-state equation solved by the discrete ordinates (S(N)) or Monte Carlo methods. (authors)

  8. The {sup 4}He(e,e'p) Cross Section at Large Missing Energy

    SciTech Connect

    J.J. van Leeuwe; H.P. Blok; J.F.J. van den Brand; H.J. Bulten; G.E. Dodge; R. Ent; W.H.A. Hesselink; E. Jans; W.J. Kasdorp; J.M. Laget; L. Lapikas; C.J.G. Onderwater; A.R. Pellegrino; C.M. Spaltro; J.J.M. Steijger; J.A. Templon; O. Unal

    1997-07-01

    The (e,e'p) reaction on {sup 4}He nuclei was studied in kinematics designed to emphasize effects of nuclear short-range correlations. The measured cross sections display a peak in the kinematical regions where two-nucleon processes are expected to dominate. Theoretical models incorporating short-range correlation effects agree reasonably with the data.

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

    SciTech Connect

    ganda, francesco (090771)

    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.

  10. Free Antineutrino Absorption Cross Section. I. Measurement of the Free Antineutrino Absorption Cross Section by Protons

    Microsoft Academic Search

    Frederick Reines; Clyde L. Cowan

    1959-01-01

    The cross section for the reaction p(nu¯, beta+)n was measured using antineutrinos (nu¯) from a powerful fission reactor at the Savannah River Plant of the United States Atomic Energy Commission. Target protons were provided by a 1.4×103 liter liquid scintillation detector in which the scintillator solution (triethylbenzene, terphyenyl, and POPOP) was loaded with a cadmium compound (cadmium octoate) to allow

  11. Theoretical study of evaporation cross sections in the synthesis of very neutron-deficient nuclei

    SciTech Connect

    Wang Chengbin; Zhang Jinjuan [Physics Department of Nanjing University, Nanjing 210008 (China); Ren, Z. Z. [Physics Department of Nanjing University, Nanjing 210008 (China); Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou 730000 (China)

    2011-07-15

    The synthesis of rare-earth neutron-deficient nuclei with large Z/N ratio {approx_equal}0.88 is studied within the framework of the standard statistical model. The fusion cross sections are calculated on the basis of the nuclear reaction video model. The deexcitation process is calculated with the help of the statistical code alice. It is found that the excitation functions can be predicted using a few exited experimental data by carefully choosing the input parameters in the statistical model. The results obtained show that a satisfactory description of the experimental evaporation cross sections requires a great reduction in the theoretical fission barriers.

  12. Cross sections for hard exclusive electroproduction of ? mesons on a hydrogen target

    NASA Astrophysics Data System (ADS)

    HERMES Collaboration; Airapetian, A.; Akopov, N.; Akopov, Z.; Aschenauer, E. C.; Augustyniak, W.; Avetissian, A.; Avetissian, E.; Barion, L.; Belostotski, S.; Bianchi, N.; Blok, H. P.; Böttcher, H.; Bonomo, C.; Borissov, A.; Bryzgalov, V.; Burns, J.; Capiluppi, M.; Capitani, G. P.; Cisbani, E.; Ciullo, G.; Contalbrigo, M.; Dalpiaz, P. F.; Deconinck, W.; de Leo, R.; Demey, M.; de Nardo, L.; de Sanctis, E.; Diefenthaler, M.; di Nezza, P.; Dreschler, J.; Düren, M.; Ehrenfried, M.; Elbakian, G.; Ellinghaus, F.; Fabbri, R.; Fantoni, A.; Frullani, S.; Gabbert, D.; Gapienko, G.; Gapienko, V.; Garibaldi, F.; Gavrilov, G.; Gharibyan, V.; Giordano, F.; Gliske, S.; Guler, H.; Hadjidakis, C.; Hasch, D.; Hill, G.; Hillenbrand, A.; Hoek, M.; Hristova, I.; Ilyichev, A.; Imazu, Y.; Ivanilov, A.; Jackson, H. E.; Joosten, S.; Kaiser, R.; Keri, T.; Kinney, E.; Kisselev, A.; Kopytin, M.; Korotkov, V.; Kravchenko, P.; Krivokhijine, V. G.; Lagamba, L.; Lamb, R.; Lapikás, L.; Lehmann, I.; Lenisa, P.; Linden-Levy, L. A.; Lopez Ruiz, A.; Lorenzon, W.; Lu, S.; Lu, X.; Mahon, D.; Makins, N. C. R.; Marianski, B.; Marukyan, H.; Miller, C. A.; Miyachi, Y.; Muccifora, V.; Murray, M.; Mussgiller, A.; Nappi, E.; Naryshkin, Y.; Nass, A.; Negodaev, M.; Nowak, W.-D.; Pappalardo, L. L.; Perez-Benito, R.; Pickert, N.; Raithel, M.; Reimer, P. E.; Reolon, A. R.; Riedl, C.; Rith, K.; Rock, S. E.; Rosner, G.; Rostomyan, A.; Rubacek, L.; Rubin, J.; Ryckbosch, D.; Salomatin, Y.; Schäfer, A.; Schnell, G.; Schüler, K. P.; Seitz, B.; Shearer, C.; Shibata, T.-A.; Shutov, V.; Stancari, M.; Statera, M.; Steijger, J. J. M.; Stenzel, H.; Stewart, J.; Stinzing, F.; Streit, J.; Taroian, S.; Thomas, E.; Trzcinski, A.; Tytgat, M.; Vandenbroucke, A.; van der Nat, P. B.; van der Steenhoven, G.; van Haarlem, Y.; van Hulse, C.; Varanda, M.; Veretennikov, D.; Vikhrov, V.; Vilardi, I.; Vogel, C.; Wang, S.; Yaschenko, S.; Ye, H.; Ye, Z.; Yen, S.; Yu, W.; Zeiler, D.; Zihlmann, B.; Zupranski, P.

    2008-01-01

    The exclusive electroproduction of ? mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off an internal hydrogen gas target. The virtual-photon cross sections were measured as a function of the Mandelstam variable t and the squared four momentum -Q of the exchanged virtual photon. A model calculation based on Generalized Parton Distributions is in fair agreement with the data at low values of |t| if power corrections are included. A model calculation based on the Regge formalism gives a good description of the magnitude and the t and Q dependences of the cross section.

  13. Cross sections for hard exclusive electroproduction of ?+ mesons on a hydrogen target

    NASA Astrophysics Data System (ADS)

    Airapetian, A.; Akopov, N.; Akopov, Z.; Aschenauer, E. C.; Augustyniak, W.; Avetissian, A.; Avetissian, E.; Barion, L.; Belostotski, S.; Bianchi, N.; Blok, H. P.; Böttcher, H.; Bonomo, C.; Borissov, A.; Bryzgalov, V.; Burns, J.; Capiluppi, M.; Capitani, G. P.; Cisbani, E.; Ciullo, G.; Contalbrigo, M.; Dalpiaz, P. F.; Deconinck, W.; de Leo, R.; Demey, M.; de Nardo, L.; de Sanctis, E.; Diefenthaler, M.; di Nezza, P.; Dreschler, J.; Düren, M.; Ehrenfried, M.; Elbakian, G.; Ellinghaus, F.; Fabbri, R.; Fantoni, A.; Frullani, S.; Gabbert, D.; Gapienko, G.; Gapienko, V.; Garibaldi, F.; Gavrilov, G.; Gharibyan, V.; Giordano, F.; Gliske, S.; Guler, H.; Hadjidakis, C.; Hasch, D.; Hill, G.; Hillenbrand, A.; Hoek, M.; Hristova, I.; Ilyichev, A.; Imazu, Y.; Ivanilov, A.; Jackson, H. E.; Joosten, S.; Kaiser, R.; Keri, T.; Kinney, E.; Kisselev, A.; Kopytin, M.; Korotkov, V.; Kravchenko, P.; Krivokhijine, V. G.; Lagamba, L.; Lamb, R.; Lapikás, L.; Lehmann, I.; Lenisa, P.; Linden-Levy, L. A.; Lopez Ruiz, A.; Lorenzon, W.; Lu, S.; Lu, X.; Mahon, D.; Makins, N. C. R.; Marianski, B.; Marukyan, H.; Miller, C. A.; Miyachi, Y.; Muccifora, V.; Murray, M.; Mussgiller, A.; Nappi, E.; Naryshkin, Y.; Nass, A.; Negodaev, M.; Nowak, W.-D.; Pappalardo, L. L.; Perez-Benito, R.; Pickert, N.; Raithel, M.; Reimer, P. E.; Reolon, A. R.; Riedl, C.; Rith, K.; Rock, S. E.; Rosner, G.; Rostomyan, A.; Rubacek, L.; Rubin, J.; Ryckbosch, D.; Salomatin, Y.; Schäfer, A.; Schnell, G.; Schüler, K. P.; Seitz, B.; Shearer, C.; Shibata, T.-A.; Shutov, V.; Stancari, M.; Statera, M.; Steijger, J. J. M.; Stenzel, H.; Stewart, J.; Stinzing, F.; Streit, J.; Taroian, S.; Thomas, E.; Trzcinski, A.; Tytgat, M.; Vandenbroucke, A.; van der Nat, P. B.; van der Steenhoven, G.; van Haarlem, Y.; van Hulse, C.; Varanda, M.; Veretennikov, D.; Vikhrov, V.; Vilardi, I.; Vogel, C.; Wang, S.; Yaschenko, S.; Ye, H.; Ye, Z.; Yen, S.; Yu, W.; Zeiler, D.; Zihlmann, B.; Zupranski, P.; Hermes Collaboration

    2008-01-01

    The exclusive electroproduction of ?+ mesons was studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off an internal hydrogen gas target. The virtual-photon cross sections were measured as a function of the Mandelstam variable t and the squared four momentum -Q2 of the exchanged virtual photon. A model calculation based on Generalized Parton Distributions is in fair agreement with the data at low values of | t | if power corrections are included. A model calculation based on the Regge formalism gives a good description of the magnitude and the t and Q2 dependences of the cross section.

  14. The 139La(n,gamma) cross section: key for the onset of the s process

    E-print Network

    R. Terlizzi

    2006-10-24

    The nuclear resonance parameters and the capture cross section of the neutron magic isotope 139La has been measured n_TOF. The description of the experimental apparata is followed by the data analysis procedures. We extracted the resonance parameters, the main nuclear quantities such as the resonance integral, the average gamma widths for s- and p-waves, the nuclear level densities and the neutron strength functions. These results represent a signifcant improvement over previous data. The deduced Maxwellian-averaged capture cross sections are important for the interpretation of the most recent spectroscopic observations in low metallicity stars.

  15. 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.

  16. Azimuthal asymmetries in the unpolarized SIDIS cross section at COMPASS

    E-print Network

    Giulio Sbrizzai for the COMPASS Collaboration

    2011-01-24

    The study of the spin structure of the nucleon and of the effects rising from the quarks transverse momentum are part of the scientific program of COMPASS, a fixed target experiment at the CERN SPS. The azimuthal asymmetries which appear in the cross-section of SIDIS off unpolarized targets can give insights on the intrinsic momentum structure of the nucleon and on the possible correlation between transverse spin and transverse momentum of the quarks. Here we present the new results for these asymmetries obtained from the COMPASS data collected with a 160 GeV/c positive muon beam impinging on a $^6LiD$ target. The asymmetries are measured for both positive and negative hadrons, and their dependence on several kinematical variable has been studied

  17. Measurements of positron-methane differential scattering cross sections

    SciTech Connect

    Przybyla, D.A.; Kauppila, W.E.; Kwan, C.K.; Smith, S.J.; Stein, T.S. [Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48202 (United States)] [Department of Physics and Astronomy, Wayne State University, Detroit, Michigan 48202 (United States)

    1997-06-01

    Relative differential cross sections (DCS{close_quote}s) have been measured for 4 to 200 eV e{sup +}-CH{sub 4} quasielastic scattering (elastic scattering plus rotational and vibrational excitations) from 30{degree} to 135{degree} in a crossed-beam experiment. The observed DCS behavior, including diffraction effects at low energies, is very similar to that found earlier for e{sup +}-Ar elastic scattering. Comparisons between (e{sup +},e{sup {minus}})-(CH{sub 4},Ar) DCS measurements suggest that observed diffraction effects may be correlated with the sign of the net interaction potential and the degree of spherical symmetry of the target. {copyright} {ital 1997} {ital The American Physical Society}

  18. 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

  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. 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)

  1. 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

  2. Cross sections for actinide burner reactors

    SciTech Connect

    Difilippo, F.C.

    1991-01-01

    Recent studies have shown the feasibility of burning higher actinides (i.e., transuranium (TRU) elements excluding plutonium) in ad hoc designed reactors (Actinide Burner Reactors: ABR) which, because of their hard neutron spectra, enhance the fission of TRU. The transmutation of long-lived radionuclides into stable or short-lived isotopes reduces considerably the burden of handling high-level waste from either LWR or Fast Breeder Reactors (FBR) fuels. Because of the large concentrations of higher actinides in these novel reactor designs the Doppler effect due to TRU materials is the most important temperature coefficient from the point of view of reactor safety. Here we report calculations of energy group-averaged capture and fission cross sections as function of temperature and dilution for higher actinides in the resolved and unresolved resonance regions. The calculations were done with the codes SAMMY in the resolved region and URR in the unresolved regions and compared with an independent calculation. 4 refs., 2 figs., 2 tabs.

  3. Electron ionization cross sections for the PH3 molecule

    NASA Astrophysics Data System (ADS)

    Kumar, Rajeev

    2014-08-01

    The partial single, double differential cross-sections with their total (sum of partial cross sections) of the phosphine (PH3) by direct and dissociative electron ionization have been evaluated by using modified Jain-Khare semi-empirical approach. To the best of my knowledge, no other data (experimental and/or theoretical) of differential cross sections is available till now for comparison. Partial and total integral ionization cross sections were also evaluated for PH3. Integral ionization cross-sections show good agreement with available experimental/or theoretical data. Ionization rate coefficients corresponding to partial ionization cross-sections have also been calculated by the Maxwell-Boltzmann distribution of energy.

  4. Determining the Uncertainty on the Total Heavy Flavor Cross Section

    SciTech Connect

    Vogt, R

    2008-07-22

    We assess the theoretical uncertainties on the total heavy quark cross section. We discuss the importance of the quark mass, the scale choice, the number of light flavors and the parton densities on the estimate of the uncertainty. At first glance, the uncertainty bands on the total charm cross sections obtained by integrating the FONLL inclusive cross section and by integrating the partonic total cross sections appear to be incompatible. We explain how this apparent difference arises and describe how the two results can be reconciled. The small charm quark mass amplifies the effect of varying the other parameters in the calculation, making the uncertainty on the total charm cross section difficult to quantify. On the other hand, the bottom quark total cross section is under much better theoretical control and differences between the two approaches are small.

  5. Color dipole cross section and inelastic structure function

    E-print Network

    Yu Seon Jeong; C. S. Kim; Minh Vu Luu; Mary Hall Reno

    2014-08-20

    Instead of starting from a theoretically motivated form of the color dipole cross section in the dipole picture of deep inelastic scattering, we start with a parametrization of the deep inelastic structure function for electromagnetic scattering with protons, and then extract the color dipole cross section. Using the parametrizations of $F_2(\\xi=x \\ {\\rm or}\\ W^2,Q^2)$ by Donnachie-Landshoff and Block et al., we find the dipole cross section from an approximate form of the presumed dipole cross section convoluted with the perturbative photon wave function for virtual photon splitting into a color dipole with massless quarks. The color dipole cross section determined this way reproduces the original structure function within about 10\\% for $0.1$ GeV$^2\\leq Q^2\\leq 10$ GeV$^2$. We discuss the large and small form of the dipole cross section and compare with other parameterizations.

  6. 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...

  7. 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.

  8. 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.

  9. Drell-Yan Cross Section in the Jet Calculus Scheme

    E-print Network

    Hidekazu Tanaka; Hirokazu Kobayashi

    2009-05-02

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

  10. Thermal neutron capture cross sections of the palladium isotopes

    Microsoft Academic Search

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

    2008-01-01

    Precise thermal neutron capture gamma-ray cross sections sigmagamma were measured for all elements with Z=1-83,90, and 92, except for He and Pm, at the Budapest Reactor. These data were evaluated with additional information from the literature to generate the Evaluated Gamma-ray Activation File (EGAF). Isotopic radiative neutron cross sections can be deduced from the total transition cross section feeding the

  11. Thermal neutron capture cross sections of the palladium isotopes

    Microsoft Academic Search

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

    2008-01-01

    Precise thermal neutron capture -ray cross sections {sub } were measured for all elements with Z=1-83,90, and 92, for He and Pm, at the Budapest Reactor. These data were evaluated with additional information from the literature to generate the Evaluated Gamma-ray Activation File (EGAF). Isotopic radiative neutron cross sections can be deduced from the total transition cross section feeding the

  12. Total elastic cross sections for metastable argon on xenon

    Microsoft Academic Search

    A. Barrios; M. Faxas; J. Li

    1993-01-01

    Total scattering cross sections have been measured using single beam attenuation of a metastable argon atom mixed ³P{sub 2,0} beam scattered from xenon. After relative velocity and angular corrections are made, preliminary data give a total scattering cross section of 700 ± 65 â«Â² (at a relative velocity of 1000 m\\/s) is found. Earlier experiments give a total cross section

  13. 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.

  14. Temperature dependence of the cross section for the fragmentation of thymine via dissociative electron attachment.

    PubMed

    Kopyra, Janina; Abdoul-Carime, Hassan

    2015-05-01

    Providing experimental values for absolute Dissociative Electron Attachment (DEA) cross sections for nucleobases at realistic biological conditions is a considerable challenge. In this work, we provide the temperature dependence of the cross section, ?, of the dehydrogenated thymine anion (T - H)(-) produced via DEA. Within the 393-443 K temperature range, it is observed that ? varies by one order of magnitude. By extrapolating to a temperature of 313 K, the relative DEA cross section for the production of the dehydrogenated thymine anion at an incident energy of 1 eV decreases by 2 orders of magnitude and the absolute value reaches approximately 6 × 10(-19) cm(2). These quantitative measurements provide a benchmark for theoretical prediction and also a contribution to a more accurate description of the effects of ionizing radiation on molecular medium. PMID:25956096

  15. Temperature dependence of the cross section for the fragmentation of thymine via dissociative electron attachment

    NASA Astrophysics Data System (ADS)

    Kopyra, Janina; Abdoul-Carime, Hassan

    2015-05-01

    Providing experimental values for absolute Dissociative Electron Attachment (DEA) cross sections for nucleobases at realistic biological conditions is a considerable challenge. In this work, we provide the temperature dependence of the cross section, ?, of the dehydrogenated thymine anion (T - H)- produced via DEA. Within the 393-443 K temperature range, it is observed that ? varies by one order of magnitude. By extrapolating to a temperature of 313 K, the relative DEA cross section for the production of the dehydrogenated thymine anion at an incident energy of 1 eV decreases by 2 orders of magnitude and the absolute value reaches approximately 6 × 10-19 cm2. These quantitative measurements provide a benchmark for theoretical prediction and also a contribution to a more accurate description of the effects of ionizing radiation on molecular medium.

  16. 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.

  17. e+e- Hadron Production Cross Sections at Belle

    NASA Astrophysics Data System (ADS)

    Crnkovic, Jason D.

    2014-12-01

    A number of production cross sections for electron-positron annihilation to a hadronic final state have been measured using the Belle dataset, which is possible given the general purpose design of the Belle detector and its large solid-angle coverage. The cross section measurements predominantly fall above 3 GeV, which still leaves the opportunity for using the dataset to systematically measure cross sections below 3 GeV. These low-energy cross sections are important for improving the precision of the Standard Model prediction for the muon anomalous magnetic moment.

  18. DBCC Software as Database for Collisional Cross-Sections

    NASA Astrophysics Data System (ADS)

    Moroz, Daniel; Moroz, Paul

    2014-10-01

    Interactions of species, such as atoms, radicals, molecules, electrons, and photons, in plasmas used for materials processing could be very complex, and many of them could be described in terms of collisional cross-sections. Researchers involved in plasma simulations must select reasonable cross-sections for collisional processes for implementing them into their simulation codes to be able to correctly simulate plasmas. However, collisional cross-section data are difficult to obtain, and, for some collisional processes, the cross-sections are still not known. Data on collisional cross-sections can be obtained from numerous sources including numerical calculations, experiments, journal articles, conference proceedings, scientific reports, various universities' websites, national labs and centers specifically devoted to collecting data on cross-sections. The cross-sections data received from different sources could be partial, corresponding to limited energy ranges, or could even not be in agreement. The DBCC software package was designed to help researchers in collecting, comparing, and selecting cross-sections, some of which could be constructed from others or chosen as defaults. This is important as different researchers may place trust in different cross-sections or in different sources. We will discuss the details of DBCC and demonstrate how it works and why it is beneficial to researchers working on plasma simulations.

  19. On the excess in the inclusive cross section

    NASA Astrophysics Data System (ADS)

    Monni, Pier Francesco; Zanderighi, Giulia

    2015-05-01

    In this note we analyse the excess in the W + W - inclusive cross section recently measured at the LHC. We point out that in fact for the ATLAS fiducial cross sections there is no excess in the measurements compared to the NLO QCD predictions. We also argue that higher order effects to the fiducial cross section are small, and tend to cancel each other, hence the inclusion of NNLO and NNLL corrections will not modify this agreement significantly. We find that at 8 TeV a substantial part of the disagreement with the NLO prediction for the total cross section observed by ATLAS is due to the extrapolation carried out with POWHEG.

  20. 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.

  1. Initial cross section for photodissociation of phosgene on Ag(111)

    NASA Astrophysics Data System (ADS)

    Zhou, X.-L.; White, J. M.

    1990-01-01

    The initial cross section for UV photodissociation of phosgene (Cl2CO) on Ag(111) at 100 K has been measured. With photon energies greater than 2.6 eV, submonolayer Cl2CO is readily photodissociated to surface Cl(a) and gas phase CO(g). The evolution of CO during photodissociation is readily monitored and used to calculate the initial photodissociation rate and cross section. The cross section is higher than the gas phase absorption cross section and is in the range of 10-18-10-19 cm2. It depends on the wavelength and the Cl2CO coverage.

  2. Common Carotid Intima Media Thickness and Ankle-Brachial Pressure Index Correlate with Local but Not Global Atheroma Burden: A Cross Sectional Study Using Whole Body Magnetic Resonance Angiography

    PubMed Central

    Weir-McCall, Jonathan R.; Khan, Faisel; Lambert, Matthew A.; Adamson, Carly L.; Gardner, Michael; Gandy, Stephen J.; Ramkumar, Prasad Guntur; Belch, Jill J. F.; Struthers, Allan D.; Rauchhaus, Petra; Morris, Andrew D.; Houston, J. Graeme

    2014-01-01

    Background Common carotid intima media thickness (CIMT) and ankle brachial pressure index (ABPI) are used as surrogate marker of atherosclerosis, and have been shown to correlate with arterial stiffness, however their correlation with global atherosclerotic burden has not been previously assessed. We compare CIMT and ABPI with atheroma burden as measured by whole body magnetic resonance angiography (WB-MRA). Methods 50 patients with symptomatic peripheral arterial disease were recruited. CIMT was measured using ultrasound while rest and exercise ABPI were performed. WB-MRA was performed in a 1.5T MRI scanner using 4 volume acquisitions with a divided dose of intravenous gadolinium gadoterate meglumine (Dotarem, Guerbet, FR). The WB-MRA data was divided into 31 anatomical arterial segments with each scored according to degree of luminal narrowing: 0?=?normal, 1?=?<50%, 2?=?50–70%, 3?=?70–99%, 4?=?vessel occlusion. The segment scores were summed and from this a standardized atheroma score was calculated. Results The atherosclerotic burden was high with a standardised atheroma score of 39.5±11. Common CIMT showed a positive correlation with the whole body atheroma score (? 0.32, p?=?0.045), however this was due to its strong correlation with the neck and thoracic segments (? 0.42 p?=?0.01) with no correlation with the rest of the body. ABPI correlated with the whole body atheroma score (? ?0.39, p?=?0.012), which was due to a strong correlation with the ilio-femoral vessels with no correlation with the thoracic or neck vessels. On multiple linear regression, no correlation between CIMT and global atheroma burden was present (? 0.13 p?=?0.45), while the correlation between ABPI and atheroma burden persisted (? ?0.45 p?=?0.005). Conclusion ABPI but not CIMT correlates with global atheroma burden as measured by whole body contrast enhanced magnetic resonance angiography in a population with symptomatic peripheral arterial disease. However this is primarily due to a strong correlation with ilio-femoral atheroma burden. PMID:24933122

  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. Comparison between the activation cross sections and integrated cross sections for the radiative capture of 14 MeV neutrons

    Microsoft Academic Search

    F. Cvelbar; A. Hudoklin; M. Potokar

    1970-01-01

    Cross sections obtained by the integration of prompt gamma-ray spectra from the radiative capture of 14 MeV neutrons in a series of elements are presented and compared wilh the activation cross sections reported by different authors. In contrast to the activation cross-section values, which are scattered between 1 mb and 10 mb as a function of mass number, the integrated

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

    SciTech Connect

    Llovet, Xavier, E-mail: xavier@ccit.ub.edu [Centres Científics i Tecnològics, Universitat de Barcelona, Lluís Solé i Sabarís 1-3, 08028 Barcelona (Spain)] [Centres Científics i Tecnològics, Universitat de Barcelona, Lluís Solé i Sabarís 1-3, 08028 Barcelona (Spain); Powell, Cedric J. [Materials Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8370 (United States)] [Materials Measurement Science Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8370 (United States); Salvat, Francesc [Facultat de Física (ECM and ICC), Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain)] [Facultat de Física (ECM and ICC), Universitat de Barcelona, Diagonal 645, 08028 Barcelona (Spain); Jablonski, Aleksander [Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw (Poland)] [Institute of Physical Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, 01-224 Warsaw (Poland)

    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.

  6. 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.

  7. Interpreting sediment transport data with channel cross section analysis

    NASA Astrophysics Data System (ADS)

    Park, J.; Hunt, J. R.

    2013-12-01

    Suspended sediment load estimation is important for the management of stream environments. However suspended load data are uncommon and scalable models are needed to take maximum advantage of the measurements available. One of the most commonly used models for correlating suspended sediment load is an empirical power law relationship (Qs=aQ^b, Qs: suspended load, Q: flow rate). However, the relationship of log-scaled suspended load to flow rate has multiple exponents for different flow regimes at a given site, so a single power law relationship is not a good fit. Thus we are exploring an alternative approach that employs channel cross section data historically collected by the US Geological Survey during stream gauge calibration. For our research, daily flow and sediment discharge were selected from about 180 possible USGS gauging sites in California. Among those, about 20 sites were relatively unaffected by human activities, and had more than three years of data including near monthly measurements of channel cross section data. From our analysis, a slope break was consistently observed in the relationship of log-scaled suspended load to flow rate as illustrated in Figure 1 for Redwood Creek at Orick, CA. Most of the selected natural sites clearly show this slope break. The slope break corresponds to a transition of flow from a flat, wide stream to flow constrained by steep banks as verified in Figure 2 for the same site. This suggests that physical factors in the streams such as shear stress are affected by this channel morphological change and result in the greater exponent of sediment load during higher flow regime. Figure1. Daily values of measured sediment transport and flow rate reported by USGS between 1970 and 2001. Figure2. Near monthly values of measured mean water depth and width reported by USGS between 1969 and 1987.

  8. 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. (Arizona Univ., Tucson, AZ (United States). 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.)

  9. The Stability of Longitudinal and Cross-Sectional Occupational Prestige Rankings

    ERIC Educational Resources Information Center

    Fossum, John A.; Moore, Michael L.

    1975-01-01

    The stability of occupational prestige rankings over time and among cross-sectional subgroups was demonstrated. Undergraduates from different regions, hometown sizes, and political orientations ranked occupations similarly in terms of relative prestige. The rank-order correlations of prestige were .88 with a 1925 study, .93 with a 1947 study, and…

  10. Gas-phase photoemission with soft x-rays: cross sections and angular distributions

    SciTech Connect

    Shirley, D.A.; Kobrin, P.H.; Truesdale, C.M.; Lindle, D.W.; Ferrett, T.A.; Heimann, P.A.; Becker, U.; Kerkhoff, H.G.; Southworth, S.H.

    1983-09-01

    A summary is presented of typical gas-phase photoemission studies based on synchrotron radiation in the 50-5000 eV range, using beam lines at the Stanford Synchrotron Radiation Laboratory. Three topics are addressed: atomic inner-shell photoelectron cross sections and asymmetries, correlation peaks in rare gases, and core-level shape resonances in molecules.

  11. Cross Sections for Electron Collisions with Carbon Monoxide

    NASA Astrophysics Data System (ADS)

    Itikawa, Yukikazu

    2015-03-01

    Cross section data are collected and reviewed for electron collisions with carbon monoxide. Collision processes included are total scattering, elastic scattering, momentum transfer, excitations of rotational, vibrational and electronic states, ionization, and dissociation. For each process, recommended values of the cross sections are presented, when possible. The literature has been surveyed through to the end of 2013.

  12. Raman scattering cross section for N2O4.

    NASA Technical Reports Server (NTRS)

    Chen, C. J.; Wu, F.

    1971-01-01

    Measurement of the Raman scattering cross section for N2O4 at a Raman shift of 7.3 micron, using a Q-switched ruby laser as an excitation source. The cross section for N2 at a Raman shift of 4.3 micron was also measured and compared with the value given by Leonard (1970).

  13. Predicting long bone loading from cross-sectional geometry

    Microsoft Academic Search

    Daniel E. Lieberman; John D. Polk; Brigitte Demes

    2004-01-01

    Long bone loading histories are com- monly evaluated using a beam model by calculating cross- sectional second moments of areas (SMAs). Without in vivo strain data, SMA analyses commonly make two ex- plicit or implicit assumptions. First, while it has long been known that axial compression superimposed on bending shifts neutral axes away from cross-sectional area cen- troids, most analyses

  14. PHOTON-PRODUCING AND NEUTRON ACTIVATION CROSS SECTIONS

    Microsoft Academic Search

    1959-01-01

    A tabulation of photon-preducing and neutron activation cross sections ; is presented primarily for use in analyzing secondary gamma emission and foil ; activities. It is intended to supplement the information currently available. ; Data are included for certain cross sections of the following elements: aluminum, ; beryllium, copper, iron, gold, lead, manganese, oxygen, and sulfur. (auth);

  15. ENERGY DEPENDENCE OF FAST-NEUTRON ACTIVATION CROSS SECTIONS

    Microsoft Academic Search

    A. E. Johnsrud; M. G. Silbert; H. H. Barschall

    1959-01-01

    Fast-neutron capture cross sections of 24 nuclides ranging from A = 51 ; to A = 197 were measured by an activation method, in the neutron energy region ; from 0.15 to 6.2 Mev. The neutron energy spreads were of the order of 0.1 Mev so ; that cross sections averaged over many energy levels of the compound nucleus were

  16. Thermal neutron activation cross sections for Kr and Xe isotopes

    Microsoft Academic Search

    E. Kondaiah; N. Ranakumar; R. W. Fink

    1968-01-01

    Quinol-clathrates of Kr and Xe have been used as solid targets for neutron activation for the first time, and 16 (n, gamma) cross sections have been determined with thermal neutrons. The epithermal neutron contribution has been taken into account by irradiating Cd covered samples. Four isomer cross-section ratios for Xe isotopes and one for Kr have also been obtained. In

  17. Molecular collision cross sections and vibrational relaxation in carbon dioxide

    Microsoft Academic Search

    R. Marriott

    1964-01-01

    A numerical method, previously developed for the calculation of partial cross sections for the collisional excitation of molecular vibrational states, has been extended to make proper allowance for the effect of the repulsive centrifugal potential term on the matrix transition elements. This treatment of molecular collisions has been applied to a study of vibrational relaxation in carbon dioxide. Cross sections

  18. A study of radar cross section measurement techniques

    Microsoft Academic Search

    Malcolm W. McDonald

    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

  19. SUPPLEMENT 1 TO APEX 515, CROSS SECTIONS FOR REACTOR ANALYSIS

    Microsoft Academic Search

    1959-01-01

    Since the publication of APEX 515, Cross Sections for Reactor ; Analysis,'I new records were added to the IBM 704 nuclear data tape. The purpose ; of this supplement is to acquaint the users of the nuclear data tape with the ; latest additions and to document the cross section data. The new or revised ; records pertain to the

  20. Neutron Capture Cross Sections: From Theory to Experiments and Back

    SciTech Connect

    Mengoni, A. [CERN, CH-1211 Geneva 23 (Switzerland); ENEA, Via Don Fiammelli, 2 - 40129 Bologna (Italy)

    2005-05-24

    The method for an experimental determination of the stellar enhancement factor for the cross section of the 151Sm(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.

  1. Neutron Capture Cross Sections: From Theory to Experiments and Back

    Microsoft Academic Search

    Alberto Mengoni

    2005-01-01

    The method for an experimental determination of the stellar enhancement factor for the cross section of the 151Sm(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.

  2. PRELIMINARY LES OVER A HYPERSONIC ELLIPTICAL CROSS-SECTION CONE

    E-print Network

    Martín, Pino

    PRELIMINARY LES OVER A HYPERSONIC ELLIPTICAL CROSS-SECTION CONE M.P. MARTIN Mechanical. The characteristics of the hypersonic flow around an elliptical- cross section cone and the computational code of transitional and turbulent flows are not fully understood. This is especially true in the hypersonic regime

  3. Radiation pressure cross-sections of fluffy interstellar grains

    Microsoft Academic Search

    R. Saija; M. A. Iatì; A. Giusto; F. Borghese; P. Denti; S. Aiello; C. Cecchi-Pestellini

    2003-01-01

    We computed, through the transition matrix method, the radiation pressure cross-sections of cosmic dust grains modelled as aggregates (clusters) of spheres of appropriate geometry. The calculation is performed without resorting to any approximation and with a computational effort that is noticeably lighter than the one required by other methods. Our results show that radiation pressure cross-sections decrease with increasing particle

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

    Microsoft Academic Search

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

    1994-01-01

    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. Supported by the Swiss National Science Foundation.

  5. Total elastic scattering cross sections for metastable argon on xenon

    Microsoft Academic Search

    J. Li; M. Faxas; J. W. Sheldon; K. A. Hardy

    1994-01-01

    The interaction potential between metastable argon (Ar*) and xenon has been determined by a measurement of the velocity dependence of the total elastic-scattering cross section for the reaction Ar*+Xe. The cross sections have been corrected for the inelastic contribution to the reaction. The potential parameters have been determined by comparing the data with potential parameters calculated with both semiclassical and

  6. Analysis of cross sections using various nuclear potential

    SciTech Connect

    Aziz, Azni Abdul [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Kulliyah of Science, International Islamic University Malaysia, 25200 Kuantan (Malaysia); Quantum Science Center, Faculty of Science, University of Malaya, 50603 Kuala Lump (Malaysia); Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Quantum Science Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Institute of Space Science, Universiti Kebangsaan Malaysia, 43600 Bangi, Se (Malaysia); Yusof, Norhasliza [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Quantum Science Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Muhammad Zamrun, F. [Quantum Science Center, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia); Jurusan Fisika FMIPA, Universitas Haluoleo Kendari, Sulawesi Tenggara, J3232 (Indonesia)

    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.

  7. A New Scaling Law of Resonance in Total Scattering Cross Section in Gases

    NASA Astrophysics Data System (ADS)

    Raju, Gorur Govinda

    2009-10-01

    Electrical discharges in gases continue to be an active area of research because of industrial applications such as power systems, environmental clean up, laser technology, semiconductor fabrication etc. A fundamental knowledge of electron-gas neutral interaction is indispensable and, the total scattering cross section is one of the quantities that have been measured extensively. The energy dependence of the total cross sections shows peaks or resonance processes that are operative in the collision process. These peaks and the energies at which they occur are shown to satisfy a broad relationship involving the polarizability and the dipole moment of the target particle. Data on 62 target particles belonging to the following species are analyzed. (Eq 1) Rare gas atoms (Eq 2) Di-atomic molecules with combinations of polar, non-polar, attaching, and non-attaching properties Poly-atomic molecules with combinations of polar, non-polar, attaching, and non-attaching properties. Methods of improving the newly identified scaling law and possible application have been identified. 1 INTRODUCTION: Data on electron-neutral interactions are one of the most fundamental in the study of gaseous electronics and an immense literature, both experimental and theoretical, has become available since about the year 1920. [1-5]. In view of the central role which these data play in all facets of gas discharges and plasma science, it is felt that a critical review of available data is timely, mainly for the community of high voltage engineers and industries connected with plasma science in general. The electron-neutral interaction, often referred to as scattering in the scientific literature, is quantified by using the quantity called the total scattering cross section (QT, m^2). In the literature on cross section, total cross section and total scattering cross section are terms used synonymously and we follow the same practice. A definition may be found in reference [1]. This paper concerns scaling of total cross section of gases at resonance energy and the electron energy at which resonance occurs. The meaning of resonance is briefly explained in the following section. Here, we use the term scaling to relate the two quantities mentioned, namely, the resonance energy and the total cross section at that energy. Consistent with the definition of scaling, if the law proposed holds, one of the two quantities mentioned above may be calculated if the other is known. Such a method is very useful in gas discharge modeling and calculation of breakdown voltages, as more fully explained in the later section of the paper. 2 DESCRIPTION OF RESONANCE: A brief description of resonance phenomena in several types of target particles, viz., atomic, poly atomic, polar, non-polar phenomena are presented. 3 PREVIOUS SCALING LAWS: A common representation of a given characteristic with as few adjustable parameters as possible is generally known as the scaling law. The Paschen curve for breakdown voltage is such a familiar scaling law. With reference to cross sections several attempts have been made to obtain a scaling law, with varying degree of success. If the cross section-energy curve is qualitatively similar without having sharp peaks and oscillations, moderately successful scaling laws may be devised. For example, the ionization cross section- energy curves for most gases follow a general pattern. Several published scaling laws are discussed. 4 A NEW SCALING LAW AND DISCUSSION: In this work the author has compiled the resonance details for more than 60 gasest hat include the range from simple atoms to complex molecules that are polyatomic, dipolar, electron-attaching and isomers. The target particles exhibit a number of distinct features, as far as their total cross section variation with electron energy is concerned as already explained.

  8. Single-Top Cross Section Measurements at ATLAS

    E-print Network

    P. Ryan; for the ATLAS Collaboration

    2009-10-20

    The single-top production cross section is one third that of the top-pair production cross section at the LHC. During the first year of data taking, the determination of the major contributions to the total single-top cross section should be achievable. Comparisons between the measured cross sections and the theoretical predictions will provide a crucial test of the standard model. These measurements should also lead to a direct measurement of |V_tb| with a precision at the level of a few percent. In addition, they will probe for new physics via the search for evidence of anomalous couplings to the top quark and measurements of additional bosonic contributions to single-top production. Methods developed to optimize the selection of single-top events in the three production channels are presented and the potential for the cross section measurements is established.

  9. 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.

  10. An electron impact cross section set for CHF3

    NASA Astrophysics Data System (ADS)

    Kushner, Mark J.; Zhang, Da

    2000-09-01

    Trifluoromethane, CHF3, is used for plasma etching of silicon compounds for microelectronics fabrication, and so there is interest in developing computer models for plasmas sustained in CHF3. Recent measurements of electron swarm parameters, and electron impact dissociation and ionization cross sections, have provided a sufficient basis to develop a working electron impact cross section set for CHF3. Such a cross section set is reported here. We found that increased energy losses from dissociative electronic excitation processes were required to reproduce experimental ionization coefficients. The cross sections for attachment are small with there being some uncertainty in their magnitude at low energies. The cross sections were used in a plasma equipment model for an inductively coupled plasma reactor and compared to discharges sustained in C2F6. For otherwise identical operating conditions, plasmas sustained in CHF3 had higher electron and lower negative ion densities.

  11. Fission cross section measurements of actinides at LANSCE

    SciTech Connect

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

    2010-01-01

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

  12. Analytical approximations for x-ray cross sections III

    SciTech Connect

    Biggs, F; Lighthill, R

    1988-08-01

    This report updates our previous work that provided analytical approximations to cross sections for both photoelectric absorption of photons by atoms and incoherent scattering of photons by atoms. This representation is convenient for use in programmable calculators and in computer programs to evaluate these cross sections numerically. The results apply to atoms of atomic numbers between 1 and 100 and for photon energiesgreater than or equal to10 eV. The photoelectric cross sections are again approximated by four-term polynomials in reciprocal powers of the photon energy. There are now more fitting intervals, however, than were used previously. The incoherent-scattering cross sections are based on the Klein-Nishina relation, but use simpler approximate equations for efficient computer evaluation. We describe the averaging scheme for applying these atomic results to any composite material. The fitting coefficients are included in tables, and the cross sections are shown graphically. 100 graphs, 1 tab.

  13. 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.

  14. Cross-section adjustment techniques for BWR adaptive simulation

    NASA Astrophysics Data System (ADS)

    Jessee, Matthew Anderson

    Computational capability has been developed to adjust multi-group neutron cross-sections to improve the fidelity of boiling water reactor (BWR) modeling and simulation. The method involves propagating multi-group neutron cross-section uncertainties through BWR computational models to evaluate uncertainties in key core attributes such as core k-effective, nodal power distributions, thermal margins, and in-core detector readings. Uncertainty-based inverse theory methods are then employed to adjust multi-group cross-sections to minimize the disagreement between BWR modeling predictions and measured plant data. For this work, measured plant data were virtually simulated in the form of perturbed 3-D nodal power distributions with discrepancies with predictions of the same order of magnitude as expected from plant data. Using the simulated plant data, multi-group cross-section adjustment reduces the error in core k-effective to less than 0.2% and the RMS error in nodal power to 4% (i.e. the noise level of the in-core instrumentation). To ensure that the adapted BWR model predictions are robust, Tikhonov regularization is utilized to control the magnitude of the cross-section adjustment. In contrast to few-group cross-section adjustment, which was the focus of previous research on BWR adaptive simulation, multigroup cross-section adjustment allows for future fuel cycle design optimization to include the determination of optimal fresh fuel assembly designs using the adjusted multi-group cross-sections. The major focus of this work is to efficiently propagate multi-group neutron cross-section uncertainty through BWR lattice physics calculations. Basic neutron cross-section uncertainties are provided in the form of multi-group cross-section covariance matrices. For energy groups in the resolved resonance energy range, the cross-section uncertainties are computed using an infinitely-dilute approximation of the neutron flux. In order to accurately account for spatial and energy resonance self-shielding effects, the multi-group cross-section covariance matrix has been reformulated to include the uncertainty in resonance correction factors, or self-shielding factors, which are used to calculate the self-shielded multi-group cross-sections used in the lattice physics neutron transport model. This is shown to change the U-238 capture cross-section uncertainty contribution to Beginning-of-Life (BOL) lattice k-infinity by 14% (i.e. 0.291% relative standard deviation in k-infinity (self-shielded) compared to 0.255% (infinitely-dilute)). Using the reformulated multi-group cross-section covariance matrix, Efficient Subspace Methods (ESM) are used to propagate multi-group cross-section uncertainty through the lattice physics calculation. ESM algorithms have been developed by H. S. Abdel-Khalik and P. J. Turinsky to calculate low-rank approximations to large, dense sensitivity and covariance matrices used in data adjustment and uncertainty propagation applications. Using ESM, the singular value spectrum of the multi-group cross-section covariance matrix reveals an effective rank of the order of 103. Using this singular value decomposition of the multigroup cross-section covariance matrix reduces the number of lattice physics calculations per lattice from ˜107 to ˜10 3. In addition, a BOL sensitivity analysis using generalized perturbation theory at the lattice physics level is shown to further reduce the rank by a factor of 5.

  15. Electron impact rotationally elastic total cross section for formamide

    SciTech Connect

    Vinodkumar, Minaxi, E-mail: minaxivinod@yahoo.co.in [V P and R P T P Science College, Vallabh Vidyanagar 388120 (India); Limbachiya, Chetan, E-mail: chetanlimbachiya2@yahoo.com [Department of Applied Physics, The M.S. University of Baroda, Vadodara 390001 (India); Desai, Hardik, E-mail: hardikdesai.phy@gmail.com; Vinodkumar, P. C., E-mail: p.c.vinodkumar@gmail.com [Department of Physics, Sardar Patel University, Vallabh Vidyanagar 388120 (India)

    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.

  16. Nuclear cross sections for heavy charged-particle transport

    SciTech Connect

    Townsend, L.W.

    1986-01-01

    The need to develop suitable methods for describing the interactions and transport of high-energy, heavy charged particles through extended matter is important for a variety of applications including astronaut exposure to space radiations, spacecraft shielding, radiobiological studies, accelerator shield design, and clinical uses in cancer therapy. Crucial to satisfactorily to these calculations are accurate values for the absorption and fragmentation cross sections. Unfortunately, experimental data for these cross sections are sparse. Hence, the theoretical and semiempirical methods must be utilized to provide the necessary cross-section values and is illustrated here. Representative results for carbon-carbon collisions are listed. Presented are absorption cross sections at several energies and fragmentation cross sections at 2.1 GeV/nucleon. The cross sections include experimental results and predictions from parameterizations and quantum-mechanical models. For absorption cross sections, the energy-independent parameterization fails at low energies, whereas the optical model calculations and energy-dependent parameterization results are in good agreement with the experimental data. For the fragmentation, reasonable agreement is obtained for some isotopes; however, large disagreements exist for others.

  17. 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.

  18. 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.

  19. Cross-sectional study of malocclusion in Spanish children

    PubMed Central

    Montiel-Company, José M.; Bellot-Arcís, Carlos; Puertes-Fernández, Neus

    2014-01-01

    Objectives: This study was conducted to determine the orthodontic treatment need of the child population of the Valencia region of Spain, employing the DAI and the IOTN, to examine the relations between treatment need, socio-economic data and gender and to assess the diagnostic agreement between the two indices. Study Design: A cross-sectional descriptive study was conducted in a random representative sample of the schoolchild population of the Valencia region of Spain. The sample size was a total of 765 children aged 12 and 15 years at 39 schools. Results: The orthodontic treatment need assessed by the DAI was 21.7% at 12 years of age and 14.1% at 15 years. The orthodontic treatment need assessed by the IOTN DHC was 20.9% at 12 years of age and 12.7% at 15 years. The diagnostic agreement between the DAI and the modified IOTN was moderate, with Kappa scores of 0.426 at 12 years of age and 0.415 for the 15-year-old group. Conclusions: Approximately 20% of the children needed orthodontic treatment. Neither gender nor social class appeared to exert a significant influence on orthodontic treatment need. Key words:Orthodontics, epidemiology, children, malocclusion. PMID:23986013

  20. Total elastic cross sections for metastable argon on xenon

    SciTech Connect

    Barrios, A.; Faxas, M.; Li, J. [and others

    1993-05-01

    Total scattering cross sections have been measured using single beam attenuation of a metastable argon atom mixed {sup 3}P{sub 2,0} beam scattered from xenon. After relative velocity and angular corrections are made, preliminary data give a total scattering cross section of 700 {plus_minus} 65 {Angstrom}{sup 2} (at a relative velocity of 1000 m/s) is found. Earlier experiments give a total cross section for metastable argon atoms scattered from xenon of approximately 754 {Angstrom}{sup 2} and 580 {Angstrom}{sup 2} (at 1000 m/s).

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

    SciTech Connect

    Tovesson, F.; Laptev, A. B. [Los Alamos National Laboratory, Los Alamos NM 87545 (United States); Hill, T. S. [Idaho National Laboratory, Idaho Falls ID 83415 (United States)

    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.

  2. Cross section to multiplicity ratios at very high energy

    NASA Astrophysics Data System (ADS)

    Block, M. M.; Stodolsky, L.

    2014-06-01

    Recent data from the LHC makes it possible to examine an old speculation that at very high energy the total multiplicity and the cross section in elementary particle interactions vary in parallel with energy. Using fits incorporating the new data, it appears that the ratios of the total, elastic, and inelastic cross sections to the average multiplicity N can in fact approach constants at very high energy. The approach to the limit is however quite slow for the total and inelastic cross sections and is not yet reached at LHC energies. The elastic ratio ?el/N at 7 TeV, however, is not far from its asymptotic value.

  3. 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.

  4. A one- and two-dimensional cross-section sensitivity and uncertainty path of the AARE (Advanced Analysis for Reactor Engineering) modular code system

    SciTech Connect

    Davidson, J.W.; Dudziak, D.J.; Higgs, C.E.; Stepanek, J.

    1988-01-01

    AARE, a code package to perform Advanced Analysis for Reactor Engineering, is a linked modular system for fission reactor core and shielding, as well as fusion blanket, analysis. Its cross-section sensitivity and uncertainty path presently includes the cross-section processing and reformatting code TRAMIX, cross-section homogenization and library reformatting code MIXIT, the 1-dimensional transport code ONEDANT, the 2-dimensional transport code TRISM, and the 1- and 2- dimensional cross-section sensitivity and uncertainty code SENSIBL. IN the present work, a short description of the whole AARE system is given, followed by a detailed description of the cross-section sensitivity and uncertainty path. 23 refs., 2 figs.

  5. The impact of parent-child interaction 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

    2015-02-01

    There is a vast amount of evidence from psychological studies that the amount of parent-child interaction affects the development of children's verbal skills and knowledge. However, despite the vast amount of literature, brain structural development associated with the amount of parent-child interaction has never been investigated. In the present human study, we used voxel-based morphometry to measure regional gray matter density (rGMD) and examined cross-sectional correlations between the amount of time spent with parents and rGMD among 127 boys and 135 girls. We also assessed correlations between the amount of time spent with parents and longitudinal changes that occurred a few years later among 106 boys and 102 girls. After correcting for confounding factors, we found negative effects of spending time with parents on rGMD in areas in the bilateral superior temporal gyrus (STG) via cross-sectional analyses as well as in the contingent areas of the right STG. We also confirmed positive effects of spending time with parents on the Verbal Comprehension score in cross-sectional and longitudinal analyses. rGMD in partly overlapping or contingent areas of the right STG was negatively correlated with age and the Verbal Comprehension score in cross-sectional analyses. Subsequent analyses revealed verbal parent-child interactions have similar effects on Verbal Comprehension scores and rGMD in the right STG in both cross-sectional and longitudinal analyses. These findings indicate that parent-child interactions affect the right STG, which may be associated with verbal skills. PMID:25653378

  6. Factors influencing the satisfaction of rural physician assistants: a cross-sectional study.

    PubMed

    Filipova, Anna A

    2014-01-01

    The purpose of the study was to determine factors that attract physician assistants (PAs) to rural settings, and what they found satisfying about their practice and community. A cross-sectional survey design was used. All PAs who were practicing in both nonmetropolitan counties and rural communities in metropolitan counties, in a single midwestern US state, served as the population for the study. A total of 414 usable questionnaires were returned of the 1,072 distributed, a 39% response rate. Factor analysis, descriptive statistics, Pearson's correlation analysis, and robust regression analyses were used. Statistical models were tested to identify antecedents of four job satisfaction factors (satisfaction with professional respect, satisfaction with supervising physician, satisfaction with authority/ autonomy, and satisfaction with workload/salary). The strongest predictor of all four job satisfaction factors was community satisfaction, followed by importance of job practice. Additionally, the four job satisfaction factors had some significant associations with importance of socialization, community importance, practice attributes (years of practice, years in current location, specialty, and facility type), job responsibilities (percentage of patient load not discussed with physician, weekly hours as PA, inpatient visits), and demographics (marital status, race, age, education). PMID:24598896

  7. Cross sections and rate constants for low-temperature 4HeH2 vibrational relaxation

    Microsoft Academic Search

    Millard H. Alexander; Paul McGuire

    1976-01-01

    Converged coupled-states integral cross sections were determined for the vibrational relaxation of the v=1 j=0 level of p-H2 in collisions with 4He. The collision energies ranged from 0.005 to 0.4 eV. The Gordon-Secrest (GS) potential was used with both a harmonic (HO) and rotating-Morse oscillator (MO) description of the H2 molecule. Additional calculations incorporated modifications in the long-range and spherically

  8. Prevalence of child sexual abuse among adolescents in Geneva: results of a cross sectional survey

    Microsoft Academic Search

    Daniel S. Halperin; Paul Bouvier; Philip D Jaffe; Roger-luc. Mounoud; Claus H. Pawlak; Jerome. Laederack; Helene Rey Wicky; Florence Astie

    1996-01-01

    AbstractObjective: To measure the cumulative prevalence of child sexual abuse in a representative sample of the adolescent population of Geneva.Design: Cross sectional survey with an anonymous self administered questionnaire centred on a factual description of sexual activities.Setting: 68 classes (17 schools) randomly selected from the 201 ninth grade classes of the public school system in Geneva.Subjects: 1193 adolescents aged 13-17

  9. Top quark pair cross section prospects in ATLAS

    E-print Network

    Andrei Gaponenko; for the ATLAS Collaboration

    2009-10-20

    The observation of the top quark will be an important milestone in ATLAS. This talk reviews methods that ATLAS plans to use to observe the top quark pair production process and measure its cross section.

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

    SciTech Connect

    Aad, G. [Albert-Ludwigs-Universitat, Freiburg (Germany). Fakultat fur Mathematik und Physik; Abbott, B. [Univ. of Oklahoma, Norman, OK (United States). Homer L. Dodge Dept. of Physics and Astronomy; Abdallah, J. [Universitat Autonoma de Barcelona and ICREA, Barcelona (Spain). Institut de Fisica d' Altes Energies; Abdelalim, A. A. [Universite de Geneve, Geneva (Switzerland). Section de Physique; Abdesselam, A. [Oxford Univ., Oxford (United Kingdom). Dept. of Physics; Abdinov, O. [Academy of Sciences, Baku (Azerbaijan). Institute of Physics; Abi, B. [Oklahoma State Univ., Stillwater, OK (United States). Dept. of Physics; Abolins, M. [Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Abramowicz, H. [Tel Aviv Univ., Tel Aviv (Israel). Raymond and Beverly Sackler School of Physics and Astronomy; Abreu, H. [Univ. Paris-Sud, Orsay (France). LAL; Acerbi, E. [Universita di Milano, Milano (Italy). Dipartimento di Fisica; INFN Sezione di Milano, Milano (Italy); Acharya, B. S. [Collegato di Udine (Italy). INFN Gruppo; ICTP, Trieste (Italy); Adams, D. L. [Brookhaven National Lab. (BNL), Upton, NY (United States). Physics Dept.; Addy, T. N. [Hampton Univ., Hampton, VA (United States); Dept. of Physics; Adelman, J. [Yale Univ., New Haven, CT (United States). Dept. of Physics; Aderholz, M. [Werner-Heisenberg-Institut, Muchen (Germany). Max-Planck-Institut fur Physik; Adomeit, S. [Ludwig Maximilian Univ., Munich (Germany). Fakultat fur Physik; Adragna, P. [Queen Mary Univ. of London, London (United Kingdom). Dept. of Physics; Adye, T. [Rutherford Appleton Laboratory, Didcot (United Kingdom). Particle Physics Dept.; Aefsky, S. [Brandeis Univ., Waltham, MA (United States). Dept. of Physics; Aguilar-Saavedra, J. A. [Universidad de Granada, Granada (Spain). Departamento de Fisica Teorica y del Cosmos and CAFPE; Siegrist, James L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    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.

  11. Electron impact ionization cross sections for C60 fullerene

    NASA Astrophysics Data System (ADS)

    Pal, Satyendra; Anshu; Singh, C.

    2011-06-01

    We have extended and generalized the modified Jain-Khare (JK) semiempirical formalism to the evaluation of partial differential and partial integral ionization cross sections for fullerenes. The differential cross sections corresponding to the production of singly, doubly and triply charged cations in the electron impact ionization of C60 were evaluated at incident electron energies of 100 and 200 eV. The partial integral ionization cross sections calculated in the energy range varying from ionization thresholds to 1000 eV revealed satisfactory agreement with the available experimental and theoretical data. The ionization rate coefficients corresponding to the various cations have also been evaluated using the presently calculated ionization cross sections and Maxwell-Boltzmann energy distributions.

  12. Stellar (n, ?)-cross sections of short-lived nuclei.

    NASA Astrophysics Data System (ADS)

    Käppeler, F.

    Stellar neutron capture cross sections are the essential input for investigating the element production via the slow neutron capture process (s-process). With the availability of accurate cross sections for the stable s-process isotopes, analyses of the abundance patterns in the various branchings of the s-process flow require also reliable cross sections for unstable nuclei with stellar half-lives down to a few days. This contribution deals with the question to which extent existing techniques can be applied for these cases, and whether a future radioactive ion beam could be used for the preparation of suited samples. As an example, recent measurements of the stellar (n, ?) cross section of 147Pm (t1/2 = 2.6 yr) are discussed.

  13. Absolute two-photon excitation cross-sections in NO

    NASA Technical Reports Server (NTRS)

    Burris, J.; Mcgee, T.; Mcilrath, T.

    1984-01-01

    A technique has been developed which allows the determination of a two-photon absorption cross-section to be made relative to the Raman scattering cross-section in nitrogen. Spatial and temporal effects associated with the lasers are ratioed out to give a result independent of laser parameters. The necessary theory to extract a cross-section from the measured ratio of a Coherent Anti-Stokes Raman Scattering (CARS) signal in N2 to a four-wave mixing signal in NO has been developed. The technique has been demonstrated on the R(22) + S(12) (J-double-prime = 9 1/2) line in NO and a cross-section of (2.9 + or - 1.8) x 10 to the -49th (cm to the 4th power)-s was determined. This technique appears to be applicable to a number of other diatomic molecules.

  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. 11. DETAIL OF DITCH CROSS SECTION WITH VISUAL SCALES. DITCH ...

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

    11. DETAIL OF DITCH CROSS SECTION WITH VISUAL SCALES. DITCH WAS BISECTED BY LOCAL DRAINAGE; VIEW TO SOUTH. - Keefe-McDerby Mine Ditch, East of East Bidwell Street between Clarksville Road & Highway 50, Folsom, Sacramento County, CA

  16. Viscosity cross sections for the heavy noble gases

    NASA Astrophysics Data System (ADS)

    McEachran, Robert P.; Stauffer, Allan Daniel

    2015-04-01

    We have calculated viscosity cross sections for argon, krypton and xenon from zero to 1 keV using the phase shifts from our previous publication [R.P. McEachran, A.D. Stauffer, Eur. Phys. J. D 68, 153 (2014)] which presented total elastic and momentum transfer cross sections for these gases. As previously, we present simple analytic fits to our results to aid in modelling plasmas containing these atoms. By using the current results and those in reference [R.P. McEachran, A.D. Stauffer, Eur. Phys. J. D 68, 153 (2014)] the first two `partial cross sections' used in the general moment method of solving the Boltzmann equation can be obtained. The agreement of our viscosity cross sections with experimentally derived results indicates the overall reliability of our calculations.

  17. Hadronic cross sections, elastic slope and physical bounds

    SciTech Connect

    Fagundes, D. A.; Menon, M. J. [Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-859 Campinas SP (Brazil)

    2013-03-25

    An almost model-independent parametrization for the ratio of the total hadronic cross section to elastic slope is discussed. Its applicability in studies of asymptotia and analyses of extensive air shower in cosmic-ray physics is also outlined.

  18. On the cyclo-synchrotron cross-section

    NASA Astrophysics Data System (ADS)

    Gliozzi, M.; Bodo, G.; Ghisellini, G.; Trussoni, E.

    1996-06-01

    The study of the synchrotron and cyclotron absorption processes and their relative cross-sections, recently analysed by Ghisellini & Svensson, is extended to the case of photons propagating along the direction of the magnetic field. In the relativistic regime we follow a quantum approach, which requires first the derivation of the particle emissivity for the assumed configuration. The expression for the cross-section coincides with that obtained through a classical treatment of the problem in the non-relativistic regime. In the frequency range where absorption is important, the cross-section is larger than the Thomson cross-section by several orders of magnitude, implying a strong coupling between radiation and magnetized plasma. The possible atrophysical implications of this process are briefly discussed; in particular, in a magnetized plasma the Eddington luminosity for synchrotron interaction can be much lower than the standard value.

  19. 30 CFR 779.25 - Cross sections, maps, and plans.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...SURFACE MINING PERMIT APPLICATIONS-MINIMUM REQUIREMENTS FOR INFORMATION ON ENVIRONMENTAL RESOURCES § 779.25 Cross sections...assistance from experts in related fields such as landscape architecture, and shall be updated as required by the regulatory...

  20. 56. CROSS SECTIONS OF CANAL AND TUNNELS. POWER CANAL, SALT ...

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

    56. CROSS SECTIONS OF CANAL AND TUNNELS. POWER CANAL, SALT RIVER RESERVOIR Courtesy of U.S.G.S., Reclamation Service - Roosevelt Power Canal & Diversion Dam, Parallels Salt River, Roosevelt, Gila County, AZ

  1. ConcepTest: Cross-Sections of Plate Boundaries

    NSDL National Science Digital Library

    The map below shows the plate configurations along the western margin of North America. Which of the four diagrams on the right best represents a cross section through the outer layers of Earth along the line X-Y?

  2. ConcepTest: Cross-Section of Plate Boundaries

    NSDL National Science Digital Library

    The map below shows the plate configurations along the western margin of North America. Which of the four diagrams on the right best represents a cross section through the outer layers of Earth along the line X-Y?

  3. 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

    Relative dielectronic-recombination cross sections for hydrogenlike argon are presented. The contributions of the KLL, KLM, KLN, KLO, and KLP groups of resonances are compared to theoretical calculations. The experimental method consists...

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

    E-print Network

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

    2012-01-15

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

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

    E-print Network

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

    2012-01-01

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

  6. Healthy Zero Energy Buildings (HZEB) Program Cross-Sectional

    E-print Network

    Healthy Zero Energy Buildings (HZEB) Program ­ Cross-Sectional Study of Contaminant Levels, Source Laboratory is an equal opportunity employer. #12;1 Final Report Healthy Zero Energy Buildings (HZEB) Program

  7. The contribution of diffusion to device upset cross sections

    NASA Technical Reports Server (NTRS)

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

    2002-01-01

    A novel technique incorporating carrier recombination, for determining the charge collection efficiency funcition is presented and applied to a realistic, 3-D, memory device to obtain the upset cross section as a function of LET and orientation of incidence.

  8. 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

  9. Cross section dependence of event rates at neutrino telescopes

    E-print Network

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

    2006-10-20

    leaves the rate of upward events essentially unchanged. Details, such as detector depth and cross section inelasticity, can influence rates. Numerical estimates of upward shower, muon, and tau event rates in the IceCube detector confirm these results....

  10. Double differential cross sections of carbonyl sulfide molecule

    NASA Astrophysics Data System (ADS)

    Kumar, Rajeev; Sanju

    2013-06-01

    Partial and total double differential cross sections corresponding to various cations produced during the direct and dissociative electron ionization of carbonyl sulfide molecule have been calculated at fixed impinging electron energies 100 and 200eV by using modified Jain-Khare semi empirical approach. The calculation for double differential cross sections is made as a function of energy loss suffered by primary electron and angle of incident. To the best of our knowledge no other data is available for the comparison.

  11. Electron impact excitation cross sections for B III

    Microsoft Academic Search

    P. S. Ganas; M. Aryafar; L. P. Gately

    1983-01-01

    A realistic analytical central potential with two adjustable parameters is used to generate wavefunctions for the ground and excited states of doubly ionized boron. Generalized oscillator strengths and integrated cross sections from threshold up to 5 keV are calculated in the Born approximation for 2s-ns, 2s-np and 2s-nd excitations. Convenient analytic formulas for the cross sections are presented.

  12. Energy Dependence of Fast-Neutron Activation Cross Sections

    Microsoft Academic Search

    A. E. Johnsrud; M. G. Silbert; H. H. Barschall

    1959-01-01

    Fast-neutron capture cross sections of 24 nuclides ranging from A=51 to A=197 have been measured by an activation method, in the neutron energy region from 0.15 to 6.2 Mev. The neutron energy spreads were of the order of 0.1 Mev so that cross sections averaged over many energy levels of the compound nucleus were measured. Activities induced in samples by

  13. Derivation of capture cross section from quasielastic excitation function

    E-print Network

    V. V. Sargsyan; G. G. Adamian; N. V. Antonenko; P. R. S. Gomes

    2013-04-18

    The relationship between the quasielastic excitation function and the capture cross section is derived. The quasielastic data is shown to be a useful tool to extract the capture cross sections and the angular momenta of the captured systems for the reactions $^{16}$O+$^{144,154}$Sm,$^{208}$Pb, $^{20}$Ne+$^{208}$Pb, and $^{32}$S+$^{90,96}$Zr at near and above the Coulomb barrier energies.

  14. MINING INTEGRAL ACTINIDES CROSS SECTIONS FROM REACTOR DATA

    Microsoft Academic Search

    PUIGH RJ

    2009-01-01

    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 ( 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

  15. Cross-section adjustment techniques for BWR adaptive simulation

    Microsoft Academic Search

    Matthew Anderson Jessee

    2008-01-01

    Computational capability has been developed to adjust multi-group neutron cross-sections to improve the fidelity of boiling water reactor (BWR) modeling and simulation. The method involves propagating multi-group neutron cross-section uncertainties through BWR computational models to evaluate uncertainties in key core attributes such as core k-effective, nodal power distributions, thermal margins, and in-core detector readings. Uncertainty-based inverse theory methods are then

  16. The evaluation and application of redundant-cross-section covariances

    SciTech Connect

    Muir, D.W.

    1986-01-01

    Certain multigroup covariance libraries, notably COVFILS-2, omit all redundant (or summed) reactions on the grounds that the information content of a well-measured total cross section, for example, is implicitly contained in the covariances of the component, or partial, reactions that add up to the total. It is shown that, while redundant reactions can play an important role in cross-section and covariance evaluation, their emission from libraries intended for applications is justifiable. 3 refs.

  17. Photodissociation cross sections and rates for CH\\/+\\/ in interstellar clouds

    Microsoft Academic Search

    K. Kirby; W. G. Roberge; R. P. Saxon; B. Liu

    1980-01-01

    Photodissociation cross sections have been calculated for transitions arising from the ground state of CH(+) to three excited states of 1Sigma(+) symmetry accessible with photon energies not greater than 13.6 eV. Two of these dissociation channels have large cross sections and are therefore particularly relevant to the destruction of CH(+) in the interstellar medium. Photodissociation rates in the interstellar radiation

  18. New fragmentation cross sections for galactic cosmic-ray propagation

    Microsoft Academic Search

    J. S. George; R. A. Mewaldt; N. E. Yanasak; M. E. Wiedenbeck; J. J. Connell

    2002-01-01

    Improvements in galactic cosmic-ray propagation model parameters are needed to fully exploit high-precision composition data such as that from the ACE and Ulysses spacecraft. Nuclear fragmentation cross section uncertainties have a significant effect on estimates of heavy nuclei spallation in the interstellar medium in certain cases. We have made new measurements of fragmentation cross sections from 56Fe and 60Ni beams

  19. Total photoproduction cross section measurement at HERA energies

    Microsoft Academic Search

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

    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 gammap total cross section has been measured by two independent methods in the gammap center of mass energy range from 90 to 290 GeV. For an

  20. Photoproduction models for total cross section and shower development

    E-print Network

    Fernando Cornet; Carlos Garcia Canal; Agnes Grau; Giulia Pancheri; Sergio Sciutto

    2014-11-19

    A model for the total photoproduction cross section based on the ansatz that resummation of infrared gluons limits the rise induced by QCD minijets in all the total cross-sections, is used to simulate extended air showers initiated by cosmic rays with the AIRES simulation program. The impact on common shower observables, especially those related with muon production, is analysed and compared with the corresponding results obtained with previous photoproduction models.

  1. Stellar neutron capture cross sections of the Lu isotopes

    Microsoft Academic Search

    K. Wisshak; F. Voss; F. Kaeppeler; L. Kazakov

    2006-01-01

    The neutron capture cross sections of 175Lu and 176Lu 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 7Li(p,n)7Be reaction by bombarding metallic Li targets with a pulsed proton beam, and capture events were registered with the Karlsruhe 4pi barium fluoride detector. The cross sections

  2. Respiratory hazards in hard metal workers: a cross sectional study.

    PubMed Central

    Meyer-Bisch, C; Pham, Q T; Mur, J M; Massin, N; Moulin, J J; Teculescu, D; Carton, B; Pierre, F; Baruthio, F

    1989-01-01

    A cross sectional study was conducted on 513 employees at three hard metal plants: 425 exposed workers (351 men, 74 women) and 88 controls (69 men, 19 women). Cough and sputum were more frequent in workers engaged in "soft powder" and presintering workshops compared with controls (12.5% and 16.5% v 3.5%). Spirometric abnormalities were more frequent among women in sintering and finishing workshops compared with control women (56.8% v 23.8%) and abnormalities of carbon monoxide test were more frequent in exposed groups than in controls; this difference was more pronounced in women (31.4% v 5.6%) than in men (18.5% v 13%). No significant correlation was observed between duration of exposure and age adjusted lung function tests. Slight abnormalities of chest radiographs (0/1, 1/1 according to ILO classification) were more frequent in exposed men than controls (12.8% v 1.9%) and mostly in soft powder workers. In subjects with abnormal chest radiographs FVC, FEV1 and carbon monoxide indices (fractional uptake of CO or CO transfer index or both) were lower compared with those with normal chest radiographs. Although relatively mild, the clinical, radiological, and functional abnormalities uncovered call for a regular supervision of workers exposed to hard metal dust. PMID:2787666

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

    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+ + Kr and Kr2+ + Kr cross sections. The measurements of symmetric Kr+ + Kr charge exchange are in good agreement with both the calculations including spin-orbit effects and previous measurements. For the symmetric Kr2+ + 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 Kr2+ + Kr ? Kr+ + Kr+ reaction show an onset near 12 eV, reaching cross sections near constant value of 1.6 Å2 with an exception near 70-80 eV.

  4. 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.

  5. 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

  6. 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.

  7. THE FREE ANTINEUTRINO ABSORPTION CROSS SECTION. PART I. MEASUREMENT OF THE FREE ANTINEUTRINO ABSORPTION CROSS SECTION. PART II. EXPECTED CROSS SECTION FROM MEASUREMENTS OF FISSION FRAGMENT ELECTRON SPECTRUM

    Microsoft Academic Search

    F. Reines; C. L. Jr. Cowan; R. E. Carter; J. J. Wagner; M. E. Wyman

    1958-01-01

    Part I. The cross section for the reactioa, vâ+ p yields BETA \\/; sup +\\/ + n, was measured using reactor antineutrinos (vâ). Target protons ; were provided by a 370 gallon liquid scintiliation detector in which the ; scintillator solution (triethylbenzene, terphenyl, and POPOP) was loaded with a ; cadmlum compound (cadmium octoate) to allow the detection of the

  8. Analytical Investigations of Varying Cross Section Microstructures on Charge Transfer in Solid Oxide Fuel Cell Electrodes

    SciTech Connect

    Nelson, George J.; Peracchio, Aldo A.; Chiu, W. K. S.

    2011-01-01

    An extended surface modeling concept (electrochemical fin) is applied to charge transport within the SOFC electrode microstructure using an analytical modeling approach analogous to thermal fin analysis. This model is distinct from similar approaches applied to SOFC electrode microstructure in its application of a governing equation that allows for variable cross-section geometry. The model presented is capable of replicating experimentally observed electrode behavior inclusive of sensitivity to microstructural geometry, which stands in contrast to existing models that apply governing equations analogous to a constant cross-section thermal fin equation. Insights learned from this study include: the establishment of a suite of dimensionless parameters and performance metrics that can be applied to assess electrode microstructure, the definition of microstructure-related transport regimes relevant to electrode design, and correlations that allow performance predictions for electrodes that provide cell structural support. Of particular note, the variable cross-section modeling approach motivates the definition of a sintering quality parameter that quantifies the degree of constriction within the conducting network of the electrode, a phenomenon that exerts influence over electrode polarization. One-dimensional models are presented for electrochemical fins of several cross-sectional geometries with the ultimate goal of developing a general tool that enables the prompt performance evaluation of electrode microstructures. Such a tool would facilitate SOFC microstructural design by focusing more detailed modeling efforts on the most promising microstructures.

  9. 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.

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

    NASA Astrophysics Data System (ADS)

    Szalmas, L.

    2014-12-01

    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.

  11. Activation cross section and isomeric cross-section ratio for the (n,2n) reaction on Ir191

    Microsoft Academic Search

    N. Patronis; C. T. Papadopoulos; S. Galanopoulos; M. Kokkoris; G. Perdikakis; R. Vlastou; A. Lagoyannis; S. Harissopulos

    2007-01-01

    The Ir191(n,2n)Ir190 cross section was measured by means of the activation technique at four neutron energies in the range 10.0 11.3 MeV. The quasimonoenergetic neutron beam was produced via the H2(d,n)He3 reaction at the 5.5 MV Tandem Van de Graaff accelerator of NCSR ``Demokritos.'' The cross section for the population of the second high spin (11-) isomeric state was measured

  12. Activation cross section and isomeric cross-section ratio for the (n,2n) reaction on ¹¹Ir

    Microsoft Academic Search

    N. Patronis; C. T. Papadopoulos; S. Galanopoulos; M. Kokkoris; G. Perdikakis; R. Vlastou; A. Lagoyannis; S. Harissopulos

    2007-01-01

    The ¹¹Ir(n,2n)¹°Ir cross section was measured by means of the activation technique at four neutron energies in the range 10.0-11.3 MeV. The quasimonoenergetic neutron beam was produced via the ²H(d,n)³He reaction at the 5.5 MV Tandem Van de Graaff accelerator of NCSR 'Demokritos'. The cross section for the population of the second high spin (11) isomeric state was measured along

  13. 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.

  14. Correlation study of predictive and descriptive metrics of speech intelligibility

    NASA Astrophysics Data System (ADS)

    Stefaniw, Abigail; Shimizu, Yasushi; Smith, Dana

    2002-11-01

    There exists a wide range of speech-intelligibility metrics, each of which is designed to encapsulate a different aspect of room acoustics that relates to speech intelligibility. This study reviews the different definitions of and correlations between various proposed speech intelligibility measures. Speech Intelligibility metrics can be grouped by two main uses: prediction of designed rooms and description of existing rooms. Two descriptive metrics still under investigation are Ease of Hearing and Acoustical Comfort. These are measured by a simple questionnaire, and their relationships with each other and with significant speech intelligibility metrics are explored. A variety of rooms are modeled and auralized in cooperation with a larger study, including classrooms, lecture halls, and offices. Auralized rooms are used to conveniently provide calculated metrics and cross-talk canceled auralizations for diagnostic and descriptive intelligibility tests. Rooms are modeled in CATT-Acoustic and auralized with a multi-channel speaker array in a hemi-anechoic chamber.

  15. Reexamination of the neutron skin thickness using neutron removal cross sections

    SciTech Connect

    Ma Chunwang; Wei Huiling; Yu Mian [Department of Physics, Henan Normal University, Xinxiang 453007 (China); Department of Life Sciences and Technology, Xinxiang Medical University, Xinxiang 453003 (China)

    2010-11-15

    The neutron removal cross section [{sigma}{sub -N}(Z)] is defined for the projectile-like fragment isotopes and extended to the lower Z isotopes in the projectile fragmentation reaction. The cross sections of fragments in 1 A GeV even {sup 42-52}Ca+{sup 12}C projectile fragmentation reactions are calculated using the statistical abrasion-ablation model. The correlations between {sigma}{sub -N}(Z) of different fragment isotopes and neutron skin thickness (S{sub n}) for finite neutron-rich nuclei are revisited. Good linear {sigma}{sub -N}(Z)-S{sub n} correlations are observed in fragment isotopes, and it is suggested that {sigma}{sub -N}(Z) be used as an observable to determine S{sub n} of neutron-rich nucleus in addition to {sigma}{sub -N} for isotopes of the projectile nucleus.

  16. Muscle strength and cross-sectional area in man: a comparison of strength-trained and untrained subjects.

    PubMed Central

    Maughan, R. J.; Watson, J. S.; Weir, J.

    1984-01-01

    This study has examined muscle strength and cross-sectional area in a group of 35 healthy untrained male subjects and 8 subjects who had been engaged in a strenuous weight-training programme. The maximum voluntary knee extension force which could be produced by the untrained subjects was 742 +/- 100 N (mean +/- SD). The trained subjects could produce a significantly (p less than 0.001) greater force (992 +/- 162 N). Cross-sectional area of the knee-extensor muscle group was 81.6 +/- 11.8 cm2 in the untrained subjects and 104.1 +/- 12.3 cm2 in the trained subjects (p less than 0.001). In the untrained subjects, a significant correlation existed between strength and muscle cross-sectional area (r = 0.56, p less than 0.001). In the same group of subjects, there was a significant inverse relationship between muscle cross-sectional area and the ratio of strength to cross-sectional area (r = 0.55, p less than 0.001). The mean ratio of strength to cross-sectional area was 9.20 +/- 1.29 for the untrained group whereas for the trained group this ratio was 9.53 +/- 1.01. It is suggested that the inverse relationship between strength per unit cross-sectional area and cross-sectional area results in part from an increased angle of pennation in the larger muscles. Images p149-a p149-b p149-c PMID:6487941

  17. Collision cross sections for few electron systems. Final report, August 1, 2992--July 31, 1995

    SciTech Connect

    Reading, J.F.; Ford, A.L.

    1995-12-31

    The purpose of this project was to produce accurate cross sections for collisionally induced reactions from the ground stated and excited states of species of ions and at present in a hot fusion plasma. The collisional constituents may be divided into two categories for the purpose of calculations: Those in which a bare projectile excites a one electron or two electron ion or atom from its ground state, or excited states to higher excited states or ionized states. Those in which the projectile has one or more electrons attached to it and excites a one electron or two electron ion or atom from its ground state, or excited states to higher excited states or ionized states. During the collision the projectile itself may change its state being simultaneously excited or ionized. Cross sections are needed typically over the whole energy range from low velocities where molecular, orbitals begin to form to high velocities where first Born or more sophisticated asymptotic theories can be used. These high energy cross sections are very useful for experimentalists to check the absolute normalization of their cross sections. The theoretical tools used were therefore both analytical and numerical in character. Numerical calculations were restricted to expansions of the wavefunctions in a set of finite hilbert basis states (FHBS). The many body aspects of the problem, i.e. the important presence of the interelectron force, or correlation mandate a careful systematic approach. But this section was tempered in our strategy by the fact that many of the cross sections needed, especially from excited states, have never been calculated or measured at all. Thus any information we can provide is useful even if later work may modify our results.

  18. Neutrino energy reconstruction and the shape of the charged current quasielastic-like total cross section

    NASA Astrophysics Data System (ADS)

    Nieves, J.; Sánchez, F.; Simo, I. Ruiz; Vacas, M. J. Vicente

    2012-06-01

    We show that because of the multinucleon mechanism effects, the algorithm used to reconstruct the neutrino energy is not adequate when dealing with quasielastic-like events, and a distortion of the total flux-unfolded cross-section shape is produced. This amounts to a redistribution of strength from high to low energies, which gives rise to a sizable excess (deficit) of low (high) energy neutrinos. This distortion of the shape leads to a good description of the MiniBooNE unfolded charged current quasielastic-like cross sections published by A. A. Aguilar-Arevalo [(MiniBooNE Collaboration), Phys. Rev. DPRVDAQ1550-7998 81, 092005 (2010)]10.1103/PhysRevD.81.092005. However, these changes in the shape are artifacts of the unfolding process that ignores multinucleon mechanisms.

  19. 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.

  20. Absolute cross sections for electron scattering from furan.

    PubMed

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

    2012-08-14

    We report results of measurements and calculations of absolute cross sections for electron scattering from furan molecules (C(4)H(4)O). 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. PMID:22897278

  1. Accuracy of respiratory inductive plethysmographic cross-sectional areas.

    PubMed

    Watson, H L; Poole, D A; Sackner, M A

    1988-07-01

    The present study was undertaken to evaluate whether the respiratory inductive plethysmograph (RIP) 1) reflects changes of cross-sectional area enclosed by its transducer band in the presence of deformations of shape or whether it 2) has a stable base line. Testing of RIP was carried out with a device incorporating a thermally compensated oscillator and digital demodulatory circuitry. This system, introduced to commerce in 1983, superceded the nonthermal compensated oscillatory and analog demodulator circuitry first used in 1977. Testing the effects of changing cross-sectional area was accomplished by stretching a standard RIP transducer band around wooden dowels placed in holes on a peg board grid to form 23 curved and 5 rectangular shapes. The output voltage from RIP was linear for both the curved and rectangular shapes for changes of cross-sectional area within a physiological range. However, the regression line of voltage vs. cross-sectional area for the rectangular shapes was parallel and slightly displaced from the regression line for the curved shapes due to mutual coupling of inductance in the corners. Base-line drift from a RIP transducer band stretched to enclose an elliptical shape was less than 2.5 mV over a 12-h observation period. Current RIP technology accurately reflects changes of cross-sectional area of physiological shapes and has a stable base line. PMID:3403473

  2. Mg in electromagnetic fields: Theoretical partial multiphoton cross sections

    SciTech Connect

    Nikolopoulos, L.A.A. [Department of Telecommunications Science and Technology, University of Peloponnese, 22 100 Tripolis (Greece)

    2005-03-01

    We present ab initio calculations of multiphoton ionization cross sections--up to four--in atomic magnesium. We have followed a configuration interaction approach with the basis set constructed in terms of L{sup 2} integrable B-spline polynomials. The multiphoton ionization cross sections are given for a range of photon energies where the ion is left in its ground state. For the two-photon ionization process we calculate the cross section as a function of the photon energy and compare with known theoretical results. We also provide the corresponding angular asymmetry parameters which determine the angular distribution of the ionized electron. We have extended the energy range of reported theoretical three-photon ionization cross section while we present the four-photon cross section in the region between the 3s and 3p ionization thresholds. In this region the 3p{sup 2} {sup 1}S autoionizing state is identified through the four-photon absorption process and the related four-photon Fano q parameter is obtained.

  3. 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.

  4. Single-top Cross Section Measurements at ATLAS

    E-print Network

    P. Ryan

    2008-11-28

    The single-top production cross section is one third that of the top-pair production cross section at the LHC. During a year of data-taking, assuming an average luminosity of 10^33 cm-2 s-1 and a CMS energy of 14 TeV, the determination of the major contributions to the total single-top cross section should be achievable. Comparisons between the measured cross sections and the theoretical predictions will provide a crucial test of the standard model. These measurements should also lead to the first direct measurement of |V_tb|, with a precision at the level of a few percent. In addition, they will probe for new physics via the search for evidence of anomalous couplings to the top quark and the measurements of additional bosonic contributions to single-top production. Methods developed to optimize the selection of single-top events in the three production channels are presented and the potential for the cross section measurements with 1 fb-1 and 30 fb-1 of integrated luminosity is established.

  5. The optimization of variable cross-section spines with temperature dependent thermal parameters

    NASA Astrophysics Data System (ADS)

    Reardon, J.; Razani, A.

    1992-08-01

    An optimization method based on a temperature correlated profile is expanded upon for the optimization of pin fins with variable cross-sections including the temperature dependence of thermal parameters. The application of this method to optimization of fin arrays is discussed. The validity of the optimization method for a single fin is demonstrated by comparison to analytical results of a special case. An example demonstrates the importance of considering temperature dependence of thermal parameters when optimizing a heat sink.

  6. Socioeconomic disparities in intimate partner violence against Native American women: a cross-sectional study

    Microsoft Academic Search

    Lorraine Halinka Malcoe; Bonnie M Duran; Juliann M Montgomery

    2004-01-01

    BACKGROUND: Intimate partner violence (IPV) against women is a global public health problem, yet data on IPV against Native American women are extremely limited. We conducted a cross-sectional study of Native American women to determine prevalence of lifetime and past-year IPV and partner injury; examine IPV in relation to pregnancy; and assess demographic and socioeconomic correlates of past-year IPV. METHODS:

  7. 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…

  8. Structural Studies of Many-Body Systems and (e,e'p) Reaction Cross Sections

    E-print Network

    A. N. Antonov; M. K. Gaidarov; M. V. Ivanov; K. A. Pavlova; C. Giusti

    2003-12-17

    Studies of one-body density matrices (ODM) are performed in various correlation methods, such as the Jastrow method, the correlated basis function method, the Green's function method and the generator coordinate method aiming to extract the absolute spectroscopic factors and overlap functions (OF) for one-nucleon removal reactions from the ODM of the target nucleus. The advantage of this method is that it avoids the complicated task of calculating the total nuclear spectral function. The procedure for extracting bound-state OF's has been applied to make calculations of the cross sections of the $(e,e^{\\prime}p)$ reaction on the closed-shell nuclei $^{16}$O and $^{40}$Ca as well as on the open-shell nucleus $^{32}$S consistently (using the same OF's) with the cross sections of $(p,d)$ and $(\\gamma,p)$ reactions on the same nuclei. The analyses of the reaction cross sections and the spectroscopic factors and the comparison with the experimental data show the particular importance of these OF's, since they contain effects of nucleon correlations (short-range and/or long-range) which are accounted for to different extent in the theoretical methods considered.

  9. 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.

  10. 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.

  11. Lanl Neutron-Induced Fission Cross Section Measurement Program

    NASA Astrophysics Data System (ADS)

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

    2014-09-01

    A well established program of neutron-induced fission cross section measurement at Los Alamos Neutron Science Center (LANSCE) is supporting the Fuel Cycle Research program (FC R&D). Combining measurements at two LANSCE facilities, the Lujan Center and the Weapons Neutron Research facility (WNR), cover neutron energies over 10 orders of magnitude: from sub-thermal up to 200 MeV. A parallel-plate fission ionization chamber was used as a fission fragment detector. The 235U(n,f) standard was used as the reference. Fission cross sections have been measured for multiple actinides. The new data presented here completes the suite of long-lived Uranium isotopes that were investigated with this experimental approach. The cross section data are presented in comparison with existing evaluations and previous measurements.

  12. 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.

  13. 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.

  14. Light stops emerging in WW cross section measurements?

    E-print Network

    Krzysztof Rolbiecki; Kazuki Sakurai

    2013-08-12

    Recent ATLAS and CMS measurements show a slight excess in the WW cross section measurement. While still consistent with the Standard Model within 1-2 sigma, the excess could be also a first hint of physics beyond the Standard Model. We argue that this effect could be attributed to the production of scalar top quarks within supersymmetric models. The stops of mstop_1 ~ 200 GeV has the right pair-production cross section and under some assumptions can significantly contribute to the final state of two leptons and missing energy. We scan this region of parameter space to identify stop mass range preferred by the WW cross section measurements. Taking one sample benchmark point we show that it can be consistent with low energy observables and Higgs sector measurements and propose a method to distinguish supersymmetric signal from the Standard Model contribution.

  15. Large cross sections for transitions with a small energy difference

    NASA Astrophysics Data System (ADS)

    McGuire, J. H.; Shakov, Kh. Kh.

    2009-05-01

    Cross sections for transitions between states with small differences in energy can be quite large. An example is the 1s-2p transition in atomic hydrogen caused by the impact of a fast charged particle [1] or a photon [3]. In such cases the actual cross section may become much larger than the simple geometric cross section. Such transitions are often difficult to observe in the laboratory. However, they can be evaluated numerically. This effect can be significant in analysis of astrophysical data, as pointed out by T. Nandi [2]. I discuss a few examples of calculations and give a physical explanation for this effect. [4pt] [1] J.H. McGuire, D. J. Land, J. G. Brennan and G. Basbas, Phys. Rev. A19, 2180 (1979).[0pt] [2] Kh.Kh. Shakov and J.H. McGuire, Phys. Rev. A67 033405 (2003). [0pt] [3] T. Nandi, private communication, 2008.

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

    SciTech Connect

    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 normalization 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.

  17. ABSOLUTE PHOTODETACHMENT CROSS-SECTION MEASUREMENTS FOR HYDROCARBON CHAIN ANIONS

    SciTech Connect

    Best, T.; Otto, R.; Wester, R. [Institut fuer Ionenphysik und Angewandte Physik, Universitaet Innsbruck, A-6020 Innsbruck (Austria); Trippel, S.; Hlavenka, P.; Von Zastrow, A.; Eisenbach, S.; Jezouin, S. [Physikalisches Institut, Universitaet Freiburg, 79104 Freiburg (Germany); Vigren, E.; Hamberg, M.; Geppert, W. D., E-mail: roland.wester@uibk.ac.at [Molecular Physics Division, Stockholm University, Stockholm (Sweden)

    2011-12-01

    Absolute photodetachment cross sections have been measured for the hydrocarbon chain anions C{sub n}H{sup -}, n = 2, 4, and 6, which are relevant for an understanding of molecular clouds in the interstellar medium. Data have been obtained for different photon energies within approximately 1 eV of the detachment threshold. With our recently developed method we have achieved a precision of better than 25% on these absolute cross sections. The experiments have been carried out by means of photodetachment tomography of the mass-selected molecular anions in a multipole radio-frequency ion trap. The measured absolute cross sections are in accordance with the empirical scaling law of Millar et al. and have allowed us to determine its free parameters. These results are important for predicting the photostability and thus the abundance of carbon chain anions in planetary atmospheres, in circumstellar envelopes, and in photon-dominated regions of interstellar molecular clouds.

  18. Dosimetry and cross section measurements at RTNS II

    SciTech Connect

    Greenwood, L.R.; Kneff, D.W.

    1987-01-01

    Numerous measurements have been conducted at TRNS-II in order to map the neutron field for materials irradiations, to measure activation cross sections, and to measure helium production cross sections. Experiments of up to two weeks duration irradiated large numbers of activation dosimetry and helium samples both close to the source and throughout the target room. Many other samples have been irradiated in piggy-back positions over periods lasting many months. All of these experiments fall into four main classes, namely, fluence-mapping, activation dosimetry, the production of long-lived isotopes, and helium generation measurements. Radiometric dosimetry and activation cross section measurements were performed at Argonne National Laboratory; helium production was measured at Rockwell International Corporation. This paper briefly summarizes the principal results of our measurements at RTNS-II; references are given for more detailed publications. 14 refs., 4 figs.

  19. Recent advances in modeling fission cross sections over intermediate structures

    SciTech Connect

    Bouland, Olivier [Los Alamos National Laboratory; Lynn, J. Eric [Los Alamos National Laboratory; Talou, Patrick [Los Alamos National Laboratory

    2009-01-01

    More accurate fission cross section calculations in presence of underlying intermediate structure are strongly desired. This paper recalls the common approximations used below the fission threshold and quantifies their impact. In particular, an exact expanded R-matrix Monte Carlo calculation of the intermediate structure, deeply mixed with the fluctuations of the class-I and II decay amplitudes, is shown. This paper also insists on the microscopic structure of the level densities as a function of the nucleus deformation and show preliminary neutron induced fission cross section calculations for {sup 239}Pu and {sup 240}Pu using newly calculated combinatorial level densities. Comparisons with recent evaluated and measured fission cross sections are made.

  20. Predicting differential cross sections of electron scattering from polyatomic molecules

    NASA Astrophysics Data System (ADS)

    Sun, Weiguo; Wang, Qi; Zhang, Yi; Li, Huidong; Feng, Hao; Fan, Qunchao

    2015-06-01

    Based on a difference converging method (DCM) and the general differential cross section (DCS) expression, an analytical formula and a converging protocol used to predict accurate values of experimentally unknown DCSs are proposed. The accurate DCSs, integral cross sections and momentum transfer cross sections of electron scattering from {{N}2}, {{H}2}O, C{{H}4}, and C{{F}3}I molecules are studied using the new formula and a set of experimental DCSs. The calculated results show that not only all known experimental DCSs are excellently reproduced but also the unknown ones are correctly predicted. This study suggests a method as a reliable and economical theoretical alternative to obtain unknown DCSs of electron scattering from a polyatomic molecule.

  1. Realistic Calculations for Neutrino-Nucleus Reactions Cross sections

    SciTech Connect

    Chasioti, V. C.; Kosmas, T. S.; Divari, P. C. [Theoretical Physics Section, University of Ioannina, GR 45110 Ioannina (Greece)

    2008-01-24

    Inelastic neutrino-nucleus reaction cross sections at low and intermediate neutrino energies are studied. The required many-body nuclear wave-functions are calculated by utilizing a version of the quasi-particle random phase approximation (QRPA) that uses realistic two-body forces. The results presented here refer to the differential, integrated and total cross sections of the neutral-current induced reaction of {nu}{sub e} with the {sup 98}Mo and {sup 40}Ar nuclei. These isotopes are considered as promising astrophysical neutrino detection targets in recent neutrino physics research.

  2. Differential cross sections for neutrino scattering on {sup 12}C

    SciTech Connect

    Kolbe, E. [Departement fuer Physik und Astronomie der Universitaet Basel (Switzerland)] [Departement fuer Physik und Astronomie der Universitaet Basel (Switzerland)

    1996-10-01

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

  3. Photon gluon fusion cross sections at HERA energy

    NASA Astrophysics Data System (ADS)

    Engelen, J. J.; Dejong, S. J.; Poletiek, M.; Vermaseren, J. A. M.

    1988-01-01

    Cross sections for heavy flavor production through photon gluon fusion in electron proton collisions are presented. The electron photon vertex is taken into account explicitly, and the Q sq of the exchanged photon ranges from nearly zero (almost real photon) to the kinematically allowed maximum. The QCD scale is set by the mass of the produced quarks. The formalism is also applicable to the production of light quarks as long as the invariant mass of the pair is sufficiently high, so cross sections for u anti-u, d anti-d, and s anti-s production are also given.

  4. Total photoproduction cross-section at very high energy

    E-print Network

    Godbole, R M; Pancheri, G; Srivastava, Y N

    2008-01-01

    In this paper we apply to photoproduction total cross-section a model we have proposed for purely hadronic processes and which is based on QCD mini-jets and soft gluon re-summation. We compare the predictions of our model with the HERA data as well as with other models. When we extend the model to cosmic ray energies, our model predicts substantially higher cross-sections at TeV energies than models based on factorization but lower than models based on mini-jets alone, without soft gluons. We discuss the origin of this difference and comment on the Froissart bound for photon induced processes.

  5. Improved Actinide Neutron Capture Cross Sections Using Accelerator Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Bauder, W.; Pardo, R. C.; Kondev, F. G.; Kondrashev, S.; Nair, C.; Nusair, O.; Palchan, T.; Scott, R.; Seweryniak, D.; Vondrasek, R.; Collon, P.; Paul, M.; Youinou, G.; Salvatores, M.; Palmotti, G.; Berg, J.; Maddock, T.; Imel, G.

    2014-09-01

    The MANTRA (Measurement of Actinide Neutron TRAnsmutations) project will improve energy-integrated neutron capture cross section data across the actinide region. These data are incorporated into nuclear reactor models and are an important piece in understanding Generation IV reactor designs. We will infer the capture cross sections by measuring isotopic ratios from actinide samples, irradiated in the Advanced Test Reactor at INL, with Accelerator Mass Spectrometry (AMS) at ATLAS (ANL). The superior sensitivity of AMS allows us to extract multiple cross sections from a single sample. In order to analyze the large number of samples needed for MANTRA and to meet the goal of extracting multiple cross sections per sample, we have made a number of modifications to the AMS setup at ATLAS. In particular, we are developing a technique to inject solid material into the ECR with laser ablation. With laser ablation, we can better control material injection and potentially increase efficiency in the ECR, thus creating less contamination in the source and reducing cross talk. I will present work on the laser ablation system and preliminary results from our AMS measurements. The MANTRA (Measurement of Actinide Neutron TRAnsmutations) project will improve energy-integrated neutron capture cross section data across the actinide region. These data are incorporated into nuclear reactor models and are an important piece in understanding Generation IV reactor designs. We will infer the capture cross sections by measuring isotopic ratios from actinide samples, irradiated in the Advanced Test Reactor at INL, with Accelerator Mass Spectrometry (AMS) at ATLAS (ANL). The superior sensitivity of AMS allows us to extract multiple cross sections from a single sample. In order to analyze the large number of samples needed for MANTRA and to meet the goal of extracting multiple cross sections per sample, we have made a number of modifications to the AMS setup at ATLAS. In particular, we are developing a technique to inject solid material into the ECR with laser ablation. With laser ablation, we can better control material injection and potentially increase efficiency in the ECR, thus creating less contamination in the source and reducing cross talk. I will present work on the laser ablation system and preliminary results from our AMS measurements. Supported by U.S. DOE, Contract No. DE-AC02-06CH11357.

  6. 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.

  7. Inelastic cross sections from gamma-ray measurements

    SciTech Connect

    Nelson, Ronald Owen [Los Alamos National Laboratory

    2010-12-06

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

  8. Experimental helium generation cross sections for fast neutrons

    NASA Astrophysics Data System (ADS)

    Kneff, D. W.; Oliver, B. M.; Nakata, M. M.; Farrar, Harry

    Total helium generation cross sections of Al, V, Fe, Ni, Cu, Zr, Mo, Au, and the separated isotopes of Fe, Ni, Cu, and Mo have been measured for ˜14.8-MeV T(d,n) neutrons and for a ˜0-32 MeV Be(d,n) neutron field. The results, obtained using high-sensitivity gas mass spectrometry, are presented in this paper along with a summary of our previous T(d,n) helium generation cross section measurements.

  9. Measurements of multiphoton action cross sections for multiphoton microscopy.

    PubMed

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

    2014-10-01

    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

  10. International evaluation cooperation Subgroup 7: Multigroup cross section processing

    SciTech Connect

    Roussin, R.W.; White, J.E. (Oak Ridge National Lab., TN (USA)); Sartori, E. (NEA Data Bank, 91 - Gif-sur-Yvette (France)); Panini, G. (ENEA, Bologna (Italy)); MacFarlane, R. (Los Alamos National Lab., NM (USA)); Muir, D. (International Atomic Energy Agency, Vienna (Austria). Nuclear Data Section); Mattes, M. (Stuttgart Univ. (Germany, F.R.). Inst. fuer Kernenergetik und Energiesysteme); Hasegawa, I

    1991-01-01

    The chairmen of the ENDF/B, JEF, EFF, and JENDL evaluated data files adopted a proposal to develop a fine-group processed cross section library based on the VITAMIN'' concept. The authors listed above, with support from others, are participating in this project. The end result will be a pseudo-problem-independent fine-group cross section library generated from the latest evaluated data in ENDF/B-VI, JEF-2, EFF-2, and JENDL-3. Initial applications of the library will be for shielding, fast reactor physics, and fusion neutronics. Progress made to date will be discussed. 8 refs.

  11. The Predictability from Skull Morphology of Temporalis and Masseter Muscle Cross-Sectional Areas in Humans.

    PubMed

    Toro-Ibacache, Viviana; Zapata MuÑoz, Victor; O'higgins, Paul

    2015-07-01

    To carry out functional simulations of the masticatory system that aim to predict strain magnitudes it is important to apply appropriate jaw-elevator muscle forces. Force magnitude estimation from directly measured muscle physiological cross-sectional area or anatomical cross-sectional area (CSA) is not possible for fossils and skeletal material from museum collections. In these cases, muscle CSAs are often estimated from bony features. This approach has been shown to be inaccurate in a prior study based on direct measurements from cadavers. Postmortem alterations as well as age changes in muscle form might explain this discrepancy. As such, the present study uses CT images from 20 living individuals to directly measure temporalis and masseter muscle CSAs and estimated cross-sectional areas (ECSAs) from bony features. The relationships between CSAs and ECSAs were assessed by comparing mean values and by examining correlations. ECSAs are up to 100% greater than CSA and the means of these variables for each muscle differ significantly. Further, ECSA is significantly correlated with CSA for temporalis but not masseter. Cranial centroid size is only significantly associated with CSA for temporalis. These findings indicate that ECSAs should be employed with caution in simulations of human masticatory system functioning; they do not reflect CSAs and it is plausible that this also applies to studies of closely related living and fossil taxa. When ECSAs are used, sensitivity analyses are required to determine the impact of potential errors. Anat Rec, 298:1261-1270, 2015. © 2015 Wiley Periodicals, Inc. PMID:25810234

  12. 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.

  13. On the relativistic electron impact K-shell (e, (3-1)e) differential cross sections for atoms

    NASA Astrophysics Data System (ADS)

    Choubisa, R.

    2015-02-01

    In this paper, we present the results of our calculation of four-fold differential cross section (4DCS) for the K-shell electron impact double ionization (DI) on various atoms in the relativistic energy regime. The 4DCS is computed from the five-fold differential cross sections (5DCS) by integrating 5DCS over either the angles of one of the ejected electrons or the scattered electron (this process is referred as an (e, (3-1)e) process). Hence, it requires, possibly feasible double coincidence techniques to supplement our findings experimentally instead of the difficult triple coincidence technique, which is required for the complete description of the DI process. The angular profile of 5DCS is scanned with the angles of one of the ejected electrons for both the (e, (3-1)e) cases. A dominant peak in the momentum transfer direction is found when the scattered and one of the ejected electrons are detected in coincidence. The effects of nucleus (Z), energies of the ejected electrons, and the scattering angle on the 4DCS have been discussed. The angular correlation of the ejected electrons has also been discussed when only the ejected electrons are detected. We consider the spin aspects by scanning the singlet and triplet contributions in the angular profile of 4DCS. We also find that the interference term of the longitudinal and transverse interaction is responsible for the strengthening of the secondary peak. We observe a clear manifestation of the effect of nucleus on the spin asymmetry for behavior targets.

  14. Progress and open questions in the physics of neutrino cross sections

    E-print Network

    L. Alvarez-Ruso; Y. Hayato; J. Nieves

    2014-09-02

    New and more precise measurements of neutrino cross sections have renewed the interest in a better understanding of electroweak interactions on nucleons and nuclei. This effort is crucial to achieve 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 scattering and the role of multi-nucleon quasielastic-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.

  15. Soda Lake Well Lithology Data and Geologic Cross-Sections

    SciTech Connect

    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.

  16. Soda Lake Well Lithology Data and Geologic Cross-Sections

    DOE Data Explorer

    Faulds, James E.

    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.

  17. Simulations of the radar cross section of a stealth aircraft

    Microsoft Academic Search

    Mauro A. Alves; Rafael J. Port; Mirabel C. Rezende

    2007-01-01

    The radar cross section (RCS) of a CAD model of the stealth bomber B-2 Spirit was simulated with the CADRCS software. Results from simulations with the aircraft model having a perfectly conducting surface and rotating about the yaw, pitch and roll axes are presented and compared with results of simulations where the surface of the model was covered with a

  18. Measurements of four-fermion cross-sections at LEP

    NASA Astrophysics Data System (ADS)

    Kopal, Miroslav

    The production of four fermions in e+e- collisions at LEP allows the verification of the Standard Model of the Electroweak Interactions in the Charged and Neutral Current Sectors. Among the four-fermion final states, the highest purity and the clearest four-fermion events are characterized by the presence of leptons in the final state. The identification of such final states in the full data sample collected by the L3 experiment at LEP in the years from 1997 through 2000 is described. The total amount of data analyzed in this thesis corresponds to the total integrated luminosity 675.5 pb-1. This thesis presents the results of the selection of the Z boson pair production together with the measurement of the cross-section for leptonic four-fermion final states, and the first measurement of cross-sections in the four-lepton and two-lepton and missing energy channels of the Zg* production with the L3 detector. The cross-section average over the whole data sample was found to be: s(e+e-?Zg *?l+l-l' +l'-) =0.087+0.030-0.026pb, s(e+e-?Zg *?l+l-n n¯) =0.062+0.032-0.027p b. This thesis also presents the results of the selection of the single W production and the cross-section measurements of the semileptonic decays of the W boson. All measurements are consistent with the Standard Model expectations.

  19. 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.

  20. Applications of cross sections for electron-molecule collision processes

    SciTech Connect

    Cartwright, D.C.

    1985-01-01

    The role of electron-molecule collision cross sections is discussed for the study of the ionospheric and auroral processes in planetary atmospheres and of discharge-pumped lasers. These two areas emphasize the importance of further theoretical and experimental studies concerning electron-impact processes. 13 refs., 3 figs., 2 tabs. (WRF)

  1. Absolute measurements of photoionization cross-sections for ions

    NASA Astrophysics Data System (ADS)

    Kjeldsen, Henrik; Folkmann, Finn; van Elp, Jan; Knudsen, Helge; West, John B.; Andersen, Torkild

    2005-06-01

    A merged-beam set-up for absolute measurements of photoionization cross-sections of ions is described. The facility is capable of recording cross-sections as low as 10 -19 cm 2 and has been used to study a large number of singly- and multiply-charged, atomic and molecular, positive and negative ions. It is based on a synchrotron radiation beam line fitted with an undulator at the storage ring ASTRID and a low-energy (˜2 keV) ion beam line. Photons in the energy range 15-200 eV are merged co-linearly with the target ions over a distance of 50 cm, and the absolute photoionization cross-section is determined from the resulting photoion yield with a typical accuracy of 10%. Different types of ion sources are available, thus permitting a large number of positive and negative, atomic and molecular, singly- and multiply-charged ions to be investigated. Emphasis is put on accurate determination of the absolute cross-sections, requiring calibration of photodiode and particle detectors together with measurements of the photon-ion overlap.

  2. SCATTERING AND CONVERSION CROSS SECTIONS IN INHOMOGENEOUS PLASMA

    Microsoft Academic Search

    Marshall H. Cohen

    1962-01-01

    A general scattering theory is developed for a magneticfield-free ; plasma, allowing for both transverse and longitudinal waves. Cross sections are ; derived, which give the scattered components in terms of the frequencies of the ; incident and scattered waves, and the intensities of the appropriate components ; in the spectrum of density variations. The theory includes several other ;

  3. High-frequency bistatic cross sections of the ocean surface

    Microsoft Academic Search

    E. W. Gill; J. Walsh

    2001-01-01

    An analysis leading to the first- and second-order bistatic cross sections of the ocean surface in the context of high-frequency ground wave radar operation is presented. Initially, a pulsed dipole source is introduced into the previously derived electric field expressions for the bistatic reception of vertically polarized radiation scattered from rough surfaces that do not vary with time. To make

  4. 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.

  5. Neutron activation cross-section of zirconium-94

    Microsoft Academic Search

    1978-01-01

    The thermal neutron activation cross-section of94Zr was found to be 49.3±0.6 millibarns. It is shown that neutron activation analysis of Zr in silicate samples with a Zr\\/U\\u000a ratio<10 has considerable uncertainty due to fission contribution. A correction factor for the fission contribution has been\\u000a determined experimentally.

  6. Determination of absolute photoionization cross sections of the phenyl radical

    E-print Network

    Neumark, Daniel M.

    Determination of absolute photoionization cross sections of the phenyl radical Niels E. Sveum sections of the phenyl radical to form the phenyl cation were measured using tunable vacuum ultraviolet synchrotron radiation coupled with photofragment translational spectroscopy. The phenyl radical was produced

  7. 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 ... I n the areas of skin health and skin diseases, the NIH's National Institute of Arthritis and Musculoskeletal ...

  8. Electron-Impact Total Ionization Cross Section of Rb.

    NASA Astrophysics Data System (ADS)

    Kim, Y.-K.; Migdalek, J.; Siegel, W.; Biero?, J.

    1997-04-01

    The Binary-Encounter-Dipole (BED) model(Y.-K. Kim and M.E. Rudd, Phys. Rev. A 50), 3954 (1994). has been applied to electron-impact ionization of Rb. The BED cross section is in good agreement with a recent experimental data.(R.S. Schappe et al., Phys. Rev. Lett. 76), 4328 (1996). The BED theory combines a modified Mott cross section with the high-incident energy behavior of the Born cross section. The required continuum f-values were calculated from Dirac-Fock continuum wave functions with a core polarization potential.(J. Migdalek and W.E. Baylis, J. Phys. B 11), L497 (1978). The cut-off radius of the matching dipole transition operator was adjusted to reproduce the position of the known minimum in the photoionization cross section.(H. Suemitsu and J.A.R. Samson, Phys. Rev. 28), 2752 (1983). The contributions of the 4p arrow 4d, 5s, and 5p autoionizing excitations were included using the plane-wave Born approximation. We also present f-values for the 5s arrow np_1/2, np_3/2 transitions for high n near the ionization threshold.

  9. NINE AND SIXTEEN GROUP CROSS SECTIONS FOR REACTOR ANALYSIS

    Microsoft Academic Search

    C. S. Robertson; E. M. Benson

    1963-01-01

    Nine and sixteen group cross sections for use in transport theory codes ; are listed. Elements included are H, Be, B, C,O, Al, Ti, Cr, Mn, Fe, Ni, Co, Y, ; Zr, Nb, Mo, Eu, Gd, Ta, W, Re, Th, U, and Pu. A discussion of the format and the ; method used to process these is included. (auth);

  10. SOME NEUTRON CROSS SECTIONS FOR MULTI-GROUP CALCULATIONS

    Microsoft Academic Search

    Tralli

    1958-01-01

    Chapters 1 through 4 deal, respectively, with neutron diffusion data, ; neutron sensor data, inelastic scattering data, and photon activation data. ; Chapter 5 consists of a list of the references to the literature cited in the ; first four chapters. The neutron diffusion data consist of the absorption, ; scattering, transport, and slowing-down cross sections. The neutron sensor data

  11. Measurement of Neutron Absorption Cross Sections with a Pile Oscillator

    Microsoft Academic Search

    J. I. Hoover; W. H. Jordan; C. D. Moak; L. Pardue; H. Pomerance; J. D. Strong; E. O. Wollan

    1948-01-01

    The following paper deals with the measurement of thermal neutron cross sections by a technique referred to as the pile oscillator. In this method, a neutron absorber is moved back and forth in a field of thermal neutrons such as that existing in a chain reactor. In the vicinity of the absorber there is a depression in the neutron flux

  12. Application of Bionics in Antenna Radar Cross Section Reduction

    Microsoft Academic Search

    Wen Jiang; Ying Liu; Shuxi Gong; Tao Hong

    2009-01-01

    Bionics principle is applied to antenna radar cross section (RCS) reduction in this letter for the first time. To authenticate the method, a novel bionic ultrawideband (UWB) antenna is proposed by use of a model of insect tentacle. Its UWB-related radiation characteristics are simulated and experimentally verified. Monostatic RCS of an insect tentacle antenna (ITA) terminated with three different loads

  13. RZ calculations for self shielded multigroup cross sections

    SciTech Connect

    Li, M.; Sanchez, R.; Zmijarevic, I.; Stankovski, Z. [Commissariat a l'Energie Atomique CEA, Direction de l'Energie Nucleaire, DEN/DM2S/SERMA/LENR, 91191 Gif-sur-Yvette Cedex (France)

    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)

  14. Nuclear cross sections, nuclear structure and stellar nucleosynthesis

    Microsoft Academic Search

    F.-K. Thielemann; D. Argast; F. Brachwitz; W. R. Hix; P. Höflich; M. Liebendörfer; G. Martinez-Pinedo; A. Mezzacappa; I. Panov; T. Rauscher

    2003-01-01

    The role of nuclear reactions (strong, weak and electromagnetic) and nuclear structure effects are discussed in a number of stellar applications. We address fusion cross sections in stellar evolution, neutrino-induced reactions in type II supernovae, electron captures in type Ia supernovae and fission in the r-process. All of this is discussed in the context of nucleosynthesis products and their role

  15. Effect of the interparticle contact cross section on SHS processes

    NASA Astrophysics Data System (ADS)

    Monasevich, T. V.

    1993-09-01

    The relationships between the contact cross section and porosity as well as the regions of dense packing porosity are obtained for systems for which the dependence of the rate of combustion on porosity was investigated. The maximum rate of combustion in the course of the synthesis of intermetallic compounds, borides, carbides, and silicides is observed in the case of the dense packing porosity.

  16. Measurement of Dijet Cross Sections With Leading Neutrons in

    E-print Network

    Measurement of Dijet Cross Sections With Leading Neutrons in Photoproduction at HERA 1 Armen. An analysis is presented of dijets in photoproduction at the ep collider HERA where a leading neutron. The average photon-proton center-of- mass energy is about 200 GeV. Mechanism of leading neutron production

  17. Cross Section; Half Longitudinal Section Showing Middle Wall Reinforced with ...

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

    Cross Section; Half Longitudinal Section Showing Middle Wall Reinforced with Arch; Part Long Section Showing Inside of External Side Wall; East Entrance; Part Side South External; Part Reflected Plan of Soffite of Floor; Part Reflected Plan of Soffite of Roof - Blenheim Covered Bridge, Spanning Schoharie River, North Blenheim, Schoharie County, NY

  18. Electron Photodetachment Cross Section of the Negative Ion of Fluorine

    Microsoft Academic Search

    A. Mandl

    1971-01-01

    The absorption spectrum of the negative ion of fluorine has been observed in shock-heated vapors of CsF. The photodetachment cross section of the fluorine ion has been measured in the wavelength region between 2100 and 3600 Å. Results are found to be in reasonable agreement with the calculated values of Robinson and Geltman.

  19. Minimum radar cross section bounds for passive radar responsive tags

    Microsoft Academic Search

    P. Bidigare; T. Stevens; B Correll; M. Beauvais

    2004-01-01

    A common problem in ground moving target indication (GMTI) radar is detecting a target with even a large radar cross section (RCS) when its line-of-sight velocity falls below the minimum detectable velocity (MDV) for that radar system. In a cooperative scenario, a target may employ a tagging device, which can shift or spread its Doppler signature to become more detectable.

  20. Radiation pressure cross sections of model fluffy interstellar particles

    Microsoft Academic Search

    R. Saija; M. A. Iatì; A. Giusto; P. Denti; F. Borghese; C. Cecchi-Pestellini; S. Aiello; B. Barsella

    2003-01-01

    Radiation presssure forces affect the dynamical behaviour of dust particles in several astrophysical environments. For a given grain mass and composition, the optical response and the radiation pressure cross sections are critically dependent on morphology. It is likely that interstellar grains take their origin from aggregation of small particles thus resulting in more or less fluffy aggregates. These kind of

  1. Radiation pressure cross sections of model fluffy interstellar particles

    Microsoft Academic Search

    Rosalba Saija; Maria Antonia Iatì; Arianna Giusto; Paolo Denti; Ferdinando Borghese; Cesare Cecchi-Pestellini

    2003-01-01

    We calculated the radiation pressure cross sections of interstellar particles modeled as aggregates of up to 200 small spheres of astronomical silicates. The calculations were performed through the transition matrix method that, once the geometry of the aggregates has been chosen, does not require any approximations. The geometry of the particles has been set up by means of a random

  2. Absolute Photodetachment Cross-section Measurements for Hydrocarbon Chain Anions

    Microsoft Academic Search

    T. Best; R. Otto; S. Trippel; P. Hlavenka; A. von Zastrow; S. Eisenbach; S. Jézouin; R. Wester; E. Vigren; M. Hamberg; W. D. Geppert

    2011-01-01

    Absolute photodetachment cross sections have been measured for the hydrocarbon chain anions C n H--, n = 2, 4, and 6, which are relevant for an understanding of molecular clouds in the interstellar medium. Data have been obtained for different photon energies within approximately 1 eV of the detachment threshold. With our recently developed method we have achieved a precision

  3. Nuclear cross sections, cosmic ray propagation and source composition

    Microsoft Academic Search

    R. Silberberg; C. H. Tsao; J. R. Letaw

    1986-01-01

    Because cosmic rays with atomic number greater than 6 undergo nuclear composition transformations as a result of nuclear collisions in the interstellar gas, isotopic and elemental source composition have to be inferred in near-earth observation with a degree of uncertainty that is proportional to the uncertainty as to cross sections. The present consideration of these uncertainties proceeds with a comparison

  4. An experimental determination of the cross section for photodesorption

    Microsoft Academic Search

    E. B. Bourdon; R. H. Prince; W. W. Duley

    1982-01-01

    Measurement of the cross section for photodesorption of an absorbing molecule on a transparent substrate shows that this process is highly inefficient. Photodesorption yields under these conditions are some four orders of magnitude lower than previously assumed. Photodesorption of molecules from interstellar dust grains will be a highly inefficient process except in certain specialized situations.

  5. Partial Radiative Recombination Cross Sections for Excited States of Hydrogen

    Microsoft Academic Search

    Patricia Marie Fazio

    1984-01-01

    In calculating the radiative recombination cross sections for interstellar H II regions usually only the electric dipole term in the expansion of the interaction Hamiltonian is kept. However, conditions present in these regions permit recombination into highly excited states and the \\

  6. 8. Photograph of a line drawing. SHEET 8, CROSS SECTION ...

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

    8. Photograph of a line drawing. SHEET 8, CROSS SECTION ON LINE EE; 9-16-1940. Assembly Building for Tank Plant for the Chrysler Corporation, Macomb County, Michigan. Delineator: E.B. - Detroit Arsenal, 6501 East Eleven Mile Road, Warren, Macomb County, MI

  7. 10. Photograph of a line drawing. SHEET 10, CROSS SECTION ...

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

    10. Photograph of a line drawing. SHEET 10, CROSS SECTION BB; 9-16-1940. Assembly Building for Tank Plant for the Chrysler Corporation, Macomb County, Michigan. Delineator: S.B. - Detroit Arsenal, 6501 East Eleven Mile Road, Warren, Macomb County, MI

  8. 7. Photograph of a line drawing. SHEET 7, CROSS SECTION ...

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

    7. Photograph of a line drawing. SHEET 7, CROSS SECTION ON LINE CC AND DD; 9-16-1940. Assembly Building for Tank Plant for the Chrysler Corporation, Macomb County, Michigan. Delineator: E.B. - Detroit Arsenal, 6501 East Eleven Mile Road, Warren, Macomb County, MI

  9. Measurement of inclusive jet cross sections in photoproduction at HERA

    Microsoft Academic Search

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

    1993-01-01

    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.

  10. 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...

  11. Photodissociation of Acetaldehyde and the Photoionization Cross Section of HCO

    NASA Astrophysics Data System (ADS)

    Shubert, V. Alvin; Pratt, Stephen T.

    2010-06-01

    Acetaldehyde was photodissociated with near UV laser light, and the methyl (CH_3) and formyl (HCO) radical fragments were photoionized with vacuum ultraviolet (VUV) light. The fragments were detected by using both time of flight mass spectrometry and velocity ion map imaging. With the former technique, simultaneous detection of both fragments provided the intensity of HCO+ relative to CH_3+ with I(HCO+)/I(CH_3+) ? 0.8. Because the absolute photoionization cross section of the CH_3 radical has been characterized (? 5 Mb) at the VUV energies of interest, the absolute photoionization cross section of HCO could be determined from the intensity ratio, yielding an HCO cross section of ? 4 Mb at 10.3 eV. However, because some of the HCO fragments could be formed with enough internal energy to undergo secondary dissociation, velocity ion map imaging was employed to determine the extent of any secondary dissociation that occurred. The translational energy distributions obtained for both the CH_3 and HCO fragments are nearly identical, indicating that no HCO fragments underwent secondary dissociation. A surprising result was the smaller photoionization cross section of HCO relative to CH_3. Comparison to the isoelectronic species of NO will be discussed and a potential explanation will be offered for this observation. This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences under contract No. DE-AC02-06CH11357.

  12. 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.

  13. Stellar neutron capture cross sections of the Lu isotopes

    SciTech Connect

    Wisshak, K.; Voss, F.; Kaeppeler, F.; Kazakov, L. [Forschungszentrum Karlsruhe, Institut fuer Kernphysik, Postfach 3640, D-76021 Karlsruhe (Germany); Institute for Physics and Power Engineering, Obninsk, Kaluga-Region (Russian Federation)

    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.

  14. 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.

  15. Nuclear Cross Section Library for Oil Well Logging Analysis

    Microsoft Academic Search

    I. Kodeli; S. Kitsos

    As part of the IRTMBA (Improved Radiation Transport Modelling for Borehole Applications) Project of the EU Community's 5th Programme a special purpose multigroup cross section library to be used in the deterministic (as well as Monte Carlo) oil well logging particle transport calculations was prepared. This library is expected to improve the prediction of the neutron and gamma spectra at

  16. Cross-sectional survey of hantavirus infection, Brazil.

    PubMed

    Limongi, Jean E; da Costa, Fabíola C; Pinto, Rogério M C; de Oliveira, Renata C; Bragagnolo, Camila; Lemos, Elba R S; de Paula, Márcia B C; Pajuaba Neto, Adalberto A; Ferreira, Marcelo S

    2009-12-01

    A cross-sectional serosurvey was conducted to assess the proportion of persons exposed to hantaviruses in a virus-endemic area of the state of Minas Gerais, Brazil. Findings of this study suggested the presence of > or =1 hantaviruses circulating in this region causing hantavirus pulmonary syndrome, mild disease, or asymptomatic infection. PMID:19961680

  17. Nomenclature a maximum width of the cross-section m

    E-print Network

    Roy, Subrata

    geometry coefficient Dh hydraulic diameter 4 / m f Fanning friction factor h height of the cross-section m / ) u(.) fluid axial velocity m/s V(.) dimensionless axial fluid velocity W average velocity m/s x, y. P. Celata et al. eds., Begell House, New York, pp. 108­113. 4 Jiang, P. X., Fan, M. H., Si, G. S

  18. 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).

  19. 44. CROSS SECTION OF GRAND CANAL (not to scale, but ...

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

    44. CROSS SECTION OF GRAND CANAL (not to scale, but representative of all six canals) Plan Sheet D-29976, Venice Canals Rehabilitation, Sheet No. 7 of 26 (delineated by T. Wu and E. Lee, March 1991) - Venice Canals, Community of Venice, Los Angeles, Los Angeles County, CA

  20. Fast neutron ineleastic scattering cross sections of /sup 238/U for states between 680 and 1530 keV

    SciTech Connect

    Shao, J.Q.; Couchell, G.P.; Egan, J.J.; Kegel, G.H.R.; Li, S.Q.; Mittler, A.; Pullen, D.J.; Schier, W.A.; Arthur, E.D.

    1986-03-01

    Neutron inelastic scattering cross sections for /sup 238/U levels between 680- and 1530-keV excitation energy have been measured in the incident neutron energy range from 0.9 to 2.2 MeV. The (n,n') time-of-flight (TOF) technique was used to obtain direct differential inelastic cross sections. Neutrons were generated using the /sup 7/Li(p,n)/sup 7/Be reaction. Experimental parameters were optimized to achieve an energy resolution of <15 keV. Level cross sections were deduced from the measured 125-deg differential scattering cross sections. The validity of this procedure was confirmed by measuring the angular distributions for nine levels at En=1.5 and 2.0 MeV. Background due to fission induced by fast neutrons was subtracted. The TOF spectra were unfolded using the method of the response function. The data were corrected for multiple scattering and neutron attenuation in disk scattering geometry using an analytic method. Theoretical calculations of the cross sections were carried out using reaction models appropriate to the description of compound nucleus and direct interaction processes. The data are compared to (n,n'..gamma..) results and the ENDF/B-V evaluation.

  1. Absolute photoionization cross-section of the methyl radical.

    SciTech Connect

    Taatjes, C. A.; Osborn, D. L.; Selby, T.; Meloni, G.; Fan, H.; Pratt, S. T.; Chemical Sciences and Engineering Division; SNL

    2008-01-01

    The absolute photoionization cross-section of the methyl radical has been measured using two completely independent methods. The CH{sub 3} photoionization cross-section was determined relative to that of acetone and methyl vinyl ketone at photon energies of 10.2 and 11.0 eV by using a pulsed laser-photolysis/time-resolved synchrotron photoionization mass spectrometry method. The time-resolved depletion of the acetone or methyl vinyl ketone precursor and the production of methyl radicals following 193 nm photolysis are monitored simultaneously by using time-resolved synchrotron photoionization mass spectrometry. Comparison of the initial methyl signal with the decrease in precursor signal, in combination with previously measured absolute photoionization cross-sections of the precursors, yields the absolute photoionization cross-section of the methyl radical; {sigma}{sub CH}(10.2 eV) = (5.7 {+-} 0.9) x 10{sup -18} cm{sup 2} and {sigma}{sub CH{sub 3}}(11.0 eV) = (6.0 {+-} 2.0) x 10{sup -18} cm{sup 2}. The photoionization cross-section for vinyl radical determined by photolysis of methyl vinyl ketone is in good agreement with previous measurements. The methyl radical photoionization cross-section was also independently measured relative to that of the iodine atom by comparison of ionization signals from CH{sub 3} and I fragments following 266 nm photolysis of methyl iodide in a molecular-beam ion-imaging apparatus. These measurements gave a cross-section of (5.4 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.460 eV, (5.5 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.466 eV, and (4.9 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.471 eV. The measurements allow relative photoionization efficiency spectra of methyl radical to be placed on an absolute scale and will facilitate quantitative measurements of methyl concentrations by photoionization mass spectrometry.

  2. Partial ionization cross-sections of acetone and 2-butanone

    NASA Astrophysics Data System (ADS)

    Vacher, J. R.; Jorand, F.; Blin-Simiand, N.; Pasquiers, S.

    2008-06-01

    The electron impact ionization of acetone and 2-butanone between 10 and 86 eV has been studied using mass spectrometry. The cross-sections are measured for the formation of molecular ions and major fragment ions which are produced. The present results display good agreement between the measured total ionization cross-sections and the calculated with the BEB model. The enthalpies of formation and the ionization energies of several fragments are evaluated using ab initio calculations. For each ketone, the molecular ion and the 43 amu ion contribute to about 80% of the total cross-section at 86 eV. The 43 amu ion, identified as the acetyl cation, is the most abundant above 15 eV. Other ions present in the spectra of acetone are (i) the 42 amu ion, detected in the range 12-86 eV, contributes to about 6% of the total cross-section at the maximum voltage used and is identified at low energy as a ketene cation, (ii) six other minor ions (39, 27, 26, 44, 29 and 15 amu) were detected above 17 eV. Five of them may result from dissociation reactions of the molecular ion while the methyl cation is issued from the 43 amu ion. In the spectra of 2-butanone, other ions are (i) the 57 amu ion detected in the range 11-86 eV and identified as the propionyl cation, contributes to about 6% of the total cross-section over the whole ionization energy range, (ii) four other minor ions (42, 29, 27 and 15 amu) were detected above 18 eV and there formation is similar to that of acetone. Effects of fragment size favour from the molecular ion, the formation of the 57 amu ion near the threshold, and at higher energy, the formation of the 43 amu ion.

  3. Tree--Based Wavelet Regression for Correlated Data using the Minimum Description Length Principle

    E-print Network

    Lee, Thomas

    Tree--Based Wavelet Regression for Correlated Data using the Minimum Description Length Principle, and that it uses the minimum description length principle to define its ``best'' estimate. The proposed procedure and correlated noise. Keywords: correlated noise, minimum description length principle, non--Gaussian noise, tree

  4. Evaluation of Neutron Cross Section of 27 Fission Product Nuclides Important for Fast Reactor

    Microsoft Academic Search

    Shungo IIJIMA; Tsuneo NAKAGAWA; Yasuyuki KIKUCHI; Masayoshi KAWAI; Hiroyuki MATSUNOBU; Koichi MAKI; Sin-iti IGARASI

    1977-01-01

    Results of evaluation of neutron cross sections are presented for 27 fission product nuclides selected as being most important for fast reactor calculation. The cross sections considered are total, elastic scattering, inelastic scattering and capture cross sections in the energy range from thermal to 15 MeV. Thermal and resonance cross sections were calculated from resonance parameters. The calculated thermal capture

  5. Very small (n,gamma) cross sections: two measurements for primordial and stellar nucleosynthesis

    Microsoft Academic Search

    U. Ratzel; M. Wiescher; H. Beer; F. Käppeler; R. Steiniger

    1989-01-01

    The measurement of neutron capture cross sections via the activation technique has been extended to cross sections in the mub range. The knowledge of small cross sections is important for the abundances of neutron magic nuclei, for the role of neutron poisons, and for primordial nucleosynthesis. Wherever the activation technique can be applied, such small cross sections can be determined

  6. A.Baghdasaryan. Jet Cross Sections and S at HERA. LOW X 2008, Kolimpari, Greece, July, 6-10 1 Jet Cross Sections and s at

    E-print Network

    A.Baghdasaryan. Jet Cross Sections and S at HERA. LOW X 2008, Kolimpari, Greece, July, 6-10 1 Jet Cross Sections and s at HERA Low X 2008, 6-10 July Kolimpary, Greece Artem Baghdasaryan Yerevan Physics.Baghdasaryan. Jet Cross Sections and S at HERA. LOW X 2008, Kolimpari, Greece, July, 6-10 2 Motivation Jets physics

  7. A measurement of the U 233 , U 235 , Pu 239 total cross sections. As well as the fission cross section of U 235 for resonance neutrons

    Microsoft Academic Search

    V. V. Sokolovsky; V. V. Vladimirsky; I. A. Radkevich; A. A. Panov

    1957-01-01

    The measurement of the interaction cross sections between resonance neutrons and fissionable isotopes are of definite importance both for reactor calculations and for the construction of various nuclear models. In this work we present the results of measurements of the U233, U235, and Pu239 total cross sections, as well as the fission cross section of U235. The measurements were performed

  8. Theory of Deep Minima in (e, 2e) Measurements of Triply Differential Cross Sections

    SciTech Connect

    Macek, Joseph H [ORNL; Sternberg, James [ORNL; Ovchinnikov, Serguei Yurevich [ORNL; Briggs, J. S. [University of Freiburg, Germany

    2010-01-01

    Deep minima in He(e,2e)He{sup +} triply differential cross sections are traced to vortices in atomic wave functions. Such vortices have been predicted earlier, but the present calculations show that they have also been observed experimentally, although not recognized as vortices. Their observation in (e,2e) measurements shows that vortices play an important role in electron correlations related to the transfer of angular momentum between incident and ejected electrons. The vortices significantly extend the list of known features that summarize the general picture of electron correlations in impact ionization.

  9. TXSAMC (transport cross sections from applied Monte Carlo): a new tool for generating shielded multigroup cross sections 

    E-print Network

    Hiatt, Matthew Torgerson

    2009-06-02

    ..............................................................................................................................166 x LIST OF FIGURES FIGURE Page 1 Comparison of multigroup and continuous energy cross sections for 23Na..........4 2 TXSAMC process flowchart..................................................................................30 3 SSR layout in x-y plane. .....................................................................................42 4 ?Partial" percent errors in each energy group for reaction-rate densities in SSR...

  10. Calculation of photoionization cross section near auto-ionizing lines and magnesium photoionization cross section near threshold

    NASA Technical Reports Server (NTRS)

    Moore, E. N.; Altick, P. L.

    1972-01-01

    The research performed is briefly reviewed. A simple method was developed for the calculation of continuum states of atoms when autoionization is present. The method was employed to give the first theoretical cross section for beryllium and magnesium; the results indicate that the values used previously at threshold were sometimes seriously in error. These threshold values have potential applications in astrophysical abundance estimates.

  11. 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.

  12. Double- and triple-differential cross sections for electron-impact ionization of helium

    SciTech Connect

    Biswas, R.; Sinha, C. [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700 032 (India)] [Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700 032 (India)

    1995-05-01

    Triple- (TDCS) and double- (DDCS) differential cross sections have been calculated for single ionization in electron-helium collisions for asymmetric geometry at intermediate and medium high energies. The TDCS and DDCS results have been presented for different kinematical situations and have been compared with the corresponding experiments. In the present prescription, the final-state wave function involves the correlation between the two continuum electrons and satisfies the three-body asymptotic boundary condition (for asymmetric geometry), which is an important criterion for reliable ionization cross sections. The sensitivity of the ionization cross sections (particularly of the TDCS) with respect to the choice of the bound-state wave function of the He atom has also been studied, using two different forms of wave function of the He atom. The binary-to-recoil peak intensity ratio against momentum transfer in TDCS is found to be in closer agreement with the experiment for the simple Hylleraas wave function than for the Hartree-Fock wave function. The DDCS results are found to be in good agreement with the experimental data of Mueller-Fiedler {ital et} {ital al}. [J. Phys. B 19, 1211 (1986)] for lower ejected energy ({ital E}{sub 2}), while for higher {ital E}{sub 2} the results are closer to the measurements of Shyn {ital et} {ital al}. [Phys. Rev. A 19, 557 (1979)] and Avaldi {ital et} {ital al}. [Nuovo Cimento D 9, 97 (1987)].

  13. Cross-sectional and longitudinal profiles of valleys and channels in Xanthe Terra on Mars

    NASA Astrophysics Data System (ADS)

    Kereszturi, A.

    2005-12-01

    On the basis of Mars Orbiter Laser Altimeter data and Viking Orbiter and Mars Global Surveyor images, cross-sectional and longitudinal profiles of channels and valleys were analyzed in Xanthe Terra on Mars. Concave and convex longitudinal profiles were observed at Bahram and Tyras Valles, respectively, while no general trend was visible at other valleys. The longitudinal profiles also showed signs of knickpoints and some short reaches with increasing elevation in the flow direction. The cross-sectional profiles of Tyras Valles show more V-shaped of upper and U-shaped of lower reaches, but the great variety of profiles of other channels suggests a complex relationship with the regional lithology/topography. Also at Tyras Valles the longitudinal profiles could be divided into upper and lower sections that probably formed at different periods under different conditions. The largest observed valleys contain small, previously unnoticed inner channels. There is no correlation between the shape of cross-sectional profiles and the direction of curvature of the valley's long axis (left/right or straight), as is found in riverbeds on the Earth, suggesting that the analyzed depressions are probably valleys and not dry riverbeds, but substantial wind-blown sedimentary infill could have modified their shape too.

  14. 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

  15. Absolute photoionization cross sections of the ions Ca+ Ni+

    NASA Astrophysics Data System (ADS)

    Hansen, J. E.; Kjeldsen, H.; Folkmann, F.; Martins, M.; West, J. B.

    2007-01-01

    Absolute measurements of the photoionization cross sections of the singly charged ions in the sequence Ca to Ni are presented, focussing on the 3p ? 3d resonance region. Major differences are found in both spectral structure and cross section as the 3d shell is filled progressively. The behaviour of the total oscillator strength is studied as well as its relation to the collapse of the 3d orbital. The 3p53d 1P term is found to have an influence on the spectra even when further 3d electrons are added and this dependence combined with the effect of Hund's rule leads to a considerable simplification in the structure of the absorption spectra before the half-filled 3d shell, while from the half-filled 3d shell Hund's rule is the main simplifying effect.

  16. Shear viscosity of hadrons with K-matrix cross sections

    NASA Astrophysics Data System (ADS)

    Wiranata, Anton; Koch, Volker; Prakash, Madappa; Wang, Xin Nian

    2013-10-01

    Shear viscosity ? and entropy density s of a hadronic resonance gas are calculated using the Chapman-Enskog and virial expansion methods using the K-matrix parametrization of hadronic cross sections which preserves the unitarity of the T matrix. In the ?-K-N-? mixture considered, a total of 57 resonances up to 2 GeV were included. Comparisons are also made to results with other hadronic cross sections such as the Breit-Wigner (BW) and, where available, experimental phase shift parameterizations. Hadronic interactions forming resonances are shown to decrease the shear viscosity and increase the entropy density leading to a substantial reduction of ?/s as the QCD phase transition temperature is approached.

  17. Realistic Calculations for Neutrino-Nucleus Reactions Cross sections

    SciTech Connect

    Chasioti, V. C.; Divari, P. C.; Kosmas, T. S. [Theoretical Physics Section, University of Ioannina, GR 45110 Ioannina (Greece)

    2007-10-12

    We evaluate differential and integrated neutrino-nucleus reactions cross sections for low and intermediate neutrino energies (0 MeV{<=}E{sub {nu}}{<=}100 MeV). We investigate the dependence on the scattering angle and initial neutrino-energy of the Fermi and Gamow-Teller type transition rates. The required many-body nuclear wave-functions are calculated by utilizing the quasi-particle random phase approximation. The results presented refer to the neutral-current scattering of {nu}{sub e} on the nuclear isotopes {sup 16}O and {sup 98}Mo which play a significant role in astrophysical neutrino studies. By exploiting our exclusive cross sections, we explore the nuclear response for these detectors to supernova neutrinos assuming Fermi-Dirac distributions for the supernova neutrino spectra.

  18. Carbon Fragmentation Cross Sections for Hadrontherapy and Space Radiation Protection

    NASA Astrophysics Data System (ADS)

    De Napoli, M.; Agodi, C.; Cirrone, G. A. P.; Cuttone, G.; Nicolosi, D.; Pandola, L.; Raciti, G.; Romano, F.; Sardina, D.; Scuderi, V.; Tropea, S.; Bondì, M.; Cappuzzello, F.; Carbone, D.; Cavallaro, M.

    2014-05-01

    Fragmentation reactions represent a serious complication in hadrontherapy and space radiation protection. In order to predict their effects, both reliable Monte Carlo codes and experimental data are needed. The shortage of precise measurements, especially of double differential cross sections, has triggered many dedicated experiments at relativistic energies. Aiming to explore the Fermi energy regime, as well, where different reaction mechanisms are involved, we measured the 12C fragmentation at 62 AMeV on a 12C and a 197Au target. A high granularity Si-CsI hodoscope allowed to identify the charge and the mass of detected fragments and measure their energy and emission angle. In this work we report the double differential cross sections for the production of different fragments as a function of the emission angle. Experimental results are compared with the GEANT-4 Monte Carlo predictions performed using two reaction models, the Quantum Molecular Dynamic and the Binary Light Ion Cascade.

  19. Evaluation of Neutron Resonance Cross Section Data at GELINA

    NASA Astrophysics Data System (ADS)

    Schillebeeckx, P.; Becker, B.; Capote, R.; Emiliani, F.; Guber, K.; Heyse, J.; Kauwenberghs, K.; Kopecky, S.; Lampoudis, C.; Massimi, C.; Mondelaers, W.; Moxon, M.; Noguere, G.; Plompen, A. J. M.; Pronyaev, V.; Siegler, P.; Sirakov, I.; Trkov, A.; Volev, K.; Zerovnik, G.

    2014-05-01

    Over the last decade, the EC-JRC-IRMM, in collaboration with other institutes such as INRNE Sofia (BG), INFN Bologna (IT), ORNL (USA), CEA Cadarache (FR) and CEA Saclay (FR), has made an intense effort to improve the quality of neutron-induced cross section data in the resonance region. These improvements relate to both the infrastructure of the facility and the measurement setup, and the data reduction and analysis procedures. As a result total and reaction cross section data in the resonance region with uncertainties better than 0.5 % and 2 %, respectively, can be produced together with evaluated data files for both the resolved and unresolved resonance region. The methodology to produce full ENDF compatible files, including covariances, is illustrated by the production of resolved resonance parameter files for 241Am, Cd and W and an evaluation for 197Au in the unresolved resonance region.

  20. 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.

  1. Experimental validation of lead cross sections for scale and MCNP

    SciTech Connect

    Henrikson, D.J.

    1995-12-01

    Moving spent nuclear fuel between facilities often requires the use of lead-shielded casks. Criticality safety that is based upon calculations requires experimental validation of the fuel matrix and lead cross section libraries. A series of critical experiments using a high-enriched uranium-aluminum fuel element with a variety of reflectors, including lead, has been identified. Twenty-one configurations were evaluated in this study. The fuel element was modelled for KENO V.a and MCNP 4a using various cross section sets. The experiments addressed in this report can be used to validate lead-reflected calculations. Factors influencing calculated k{sub eff} which require further study include diameters of styrofoam inserts and homogenization.

  2. 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.

  3. Nonlocal effects in the nucleus-nucleus fusion cross section

    SciTech Connect

    Galetti, D.; Candido Ribeiro, M.A. (Instituto de Fisica Teorica, Universidade Estadual Paulista, Rua Pamplona 145, CEP 01405, Sao Paulo, Sao Paulo (Brazil))

    1994-10-01

    Effects of the nonlocality of factorizable potentials are taken into account in the calculation of nucleus-nucleus fusion cross section through an effective mass approach. This cross section makes use of the tunneling factor calculated for the nonlocal barrier, without the explicit introduction of any result coming from coupled channel calculation, besides the approximations of Hill-Wheeler and Wong. Its new expression embodies the nonlocal effects in a factor which redefines the local potential barrier curvature. Applications to different systems, namely, [sup 16]O+[sup 59]Co, [sup 16,18]O+[sup 58,60,64]Ni, and [sup 16,18]O+[sup 63,65]Cu are presented, where the nonlocal range is treated as a free parameter.

  4. Cross sections for atomic displacements in solids by fast positrons

    SciTech Connect

    Oen, Ordean S.

    1987-09-01

    The Mott series has been used to calculate the cross section for atomic displacements produced in elastic collisions between relativistic positrons and atomic nuclei. The Kinchin and Pease displacement model was used. Several elements spanning the atomic table were treated using positron energies ranging from threshold to several tens of MeV. The results are compared with previous calculations for relativistic electrons. It is found that for the same energy and atomic number the positron cross sections are always smaller (up to a factor of 5 or more). It is also found that the McKinley-Fesbach formula which is frequently used in radiation damage analysis is even less reliable for positrons than for electrons. 9 refs.

  5. Cross sections for atomic displacements in solids by fast positrons

    NASA Astrophysics Data System (ADS)

    Oen, Ordean S.

    1988-06-01

    The Mott series has been used to calculate the cross section for atomic displacements produced in elastic collisions between relativistic positrons and atomic nuclei. The Kinchin and Pease displacement model was used. Several elements spanning the atomic table were treated using positron energies ranging from threshold to several tens of MeV. The results are compared with previous calculations for relativistic electrons. It is found that for the same energy and atomic number the positron cross sections are always smaller (up to a factor of 5 or more). It is also found that the McKinley-Feshbach formula, which is frequently used in radiation damage analysis, is even less reliable for positrons than for electrons.

  6. Hadronic Cross Section Measurement at Bes-Iii

    NASA Astrophysics Data System (ADS)

    Schumann, Sven

    2014-12-01

    Measurements of the R ratio are closely related to two pre quantities, the anomalous magnetic moment of the muon (g - 2), and the value of the electromagnetic fine structure constant ? { QED}(M2Z). Hadronic contributions to both quantities can be derived via dispersion integrals, using experimental R data as input. For the phenomenological evaluations of these contributions, different energy ranges of hadronic cross section data are required. At BES-III, Initial State Radiation (ISR) from an existing ?(3770) dataset will be used for measurements of hadronic cross sections below ? s = 2 GeV, while for higher energies a dedicated energy scan program will be performed up to ? s = 4.5 GeV.

  7. First measurements of positronium total scattering cross sections

    Microsoft Academic Search

    D. M. Spektor; D. A. L. Paul

    1975-01-01

    A new type of experiment has been devised in which ortho-positronium diffusion to the metal walls of a series of parallel-sided\\u000a cells is studied by measuring the annihilation lifetimes. Experimental results are subjected to an analysis in which two parameters\\u000a are varied to give a best fit, one of the two parameters being the scattering cross section. The method requires

  8. 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.

  9. 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.

  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. Neutron-Induced Cross Sections Measurements of Calcium

    SciTech Connect

    Guber, Klaus H [ORNL; Kopecky, S. [EC-JRC-IRMM, Geel, Belgium; Schillebeeckx, P. [EC-JRC-IRMM, Geel, Belgium; Kauwenberghs, K. [EC-JRC-IRMM, Geel, Belgium; Siegler, P. [EC-JRC-IRMM, Geel, Belgium

    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.

  12. 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.

  13. 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}.

  14. Observation of very large electromagnetic dissociation cross sections

    Microsoft Academic Search

    John C. Hill; F. K. Wohn; D. D. Schwellenbach; A. R. Smith

    1991-01-01

    An electromagnetic dissociation (ED) cross section of 3.16+\\/-0.23 b was observed for 197Au(238U, X)196Au with 0.96 GeV\\/ nucleon 238U projectiles. The gross features of ED are reproduced in a Weizsäcker-Williams (WW) calculation, but the projectile charge dependence is weaker than expected from WW. WW calculations are extended to the regime of energies of the next generation of relativistic heavy-ion colliders.

  15. Coupling Extraction From Off-Shell Cross-sections

    E-print Network

    Baradhwaj Coleppa; Tanumoy Mandal; Subhadip Mitra

    2014-10-09

    In this note, we present a novel method of extracting the couplings of a new heavy particle to the Standard Model states. Contrary to the usual discovery process which involves studying the on-shell production, we look at regions away from resonance to take advantage of the simple scaling of the cross-section with the couplings. We apply the procedure to the case of a heavy quark as an illustration.

  16. Nucleon-nucleon cross sections in dense nuclear matter

    Microsoft Academic Search

    H. F. Zhang; Z. H. Li; U. Lombardo; P. Y. Luo; F. Sammarruca; W. Zuo

    2007-01-01

    We present microscopic calculations of cross sections for scattering of identical and nonidentical nucleons in symmetric nuclear matter at various densities, using the Brueckner-Hartree-Fock approximation scheme with the Argonne v14 potential including the contribution of microscopic three-body forces. We investigate separately the effects of three-body forces on the effective mass and on the scattering amplitude. In the present calculation, the

  17. Nucleon-nucleon cross sections in dense nuclear matter

    Microsoft Academic Search

    H. F. Zhang; Z. H. Li; U. Lombardo; P. Y. Luo; W. Zuo; F. Sammarruca

    2007-01-01

    We present microscopic calculations of cross sections for scattering of identical and nonidentical nucleons in symmetric nuclear matter at various densities, using the Brueckner-Hartree-Fock approximation scheme with the Argonne v potential including the contribution of microscopic three-body forces. We investigate separately the effects of three-body forces on the effective mass and on the scattering amplitude. In the present calculation, the

  18. Neutron Activation Cross Sections with Sb-Be Neutrons

    Microsoft Academic Search

    R. L. Macklin; N. H. Lazar; W. S. Lyon

    1957-01-01

    The neutron activation cross sections near 25 kev have been measured for about 50 nuclei. Gamma-ray scintillation spectrometers with known efficiency were used to compare the radioactivities produced by the several nuclei with I128. This gave a significant increase in sensitivity and precision over direct beta-counting methods in many cases. Absolute standardization was obtained through scintillation-beta-counting the I128 in NaI(Tl)

  19. Measurements of 14 MeV Neutron Activation Cross Sections

    Microsoft Academic Search

    Rudolf Pepelnik; Bernd Anders; Beni M. Bahal

    1986-01-01

    In the neutron generator facility KORONA a neutron flux of 3 · 10 n\\/cms with an energy of 14.7 ± 0.3 MeV is available. A fast rabbit system transfers samples within 140 ms to the detector station. For activation analysis work a variety of reaction cross sections were determined:The reaction products have half-lives between 0.35 s and 64 d. For

  20. The thermal neutron activation cross section of 105 Ru

    Microsoft Academic Search

    B. L. Sharma

    1960-01-01

    Summary  In order to calculate the thermal neutron activation cross section of105Ru, the enriched104Ru was exposed to a thermal neutron flux of 1.2·1014 neutrons cm?2s?1. After the decay of the 40-day activity of103Ru, the silver impurity was removed and the contributions from Co and Eu impurities were subtracted. The ?-ray energies and\\u000a the coincidence results were consistent with the previously established

  1. Cross section uncertainties in the gallium neutrino source experiments

    Microsoft Academic Search

    W. C. Haxton

    1998-01-01

    The 51Cr neutrino source experiments play a unique role in testing overall operations of the GALLEX and SAGE solar neutrino experiments. Recently Hata and Haxton argued that the excited-state contribution to the 71Ga cross section for 51Cr neutrino absorption might not be known reliably, despite forward-angle (p,n) measurements. A large-basis shell model calculation reported here indicates that the unusual situation

  2. 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.

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

    Microsoft Academic Search

    Søren Dyøe Agger; Jorn Dyøe Hedegaard Povlsen

    2006-01-01

    A thorough investigation of the emission and absorption spectra of the (3F4,3H6) band in thulium doped silica fibers has been performed. All the basic parameters of thulium in silica have been extracted with the purpose of further analysis in laser and amplifier simulations. The experimental methods used to obtain the scaled cross sections have been carefully selected in order to

  4. ACTIVIA: Calculation of Isotope Production Cross-sections and Yields

    E-print Network

    Back, J J

    2007-01-01

    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.

  5. 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.

  6. ACTIVIA: Calculation of isotope production cross-sections and yields

    Microsoft Academic Search

    J. J. Back; Y. A. Ramachers

    2008-01-01

    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

  7. Overview of recent U235 neutron cross section evaluation work

    SciTech Connect

    Lubitz, C. [Lockheed Martin Corp., Schenectady, NY (United States)

    1998-10-01

    This report is an overview (through 1997) of the U235 neutron cross section evaluation work at Oak Ridge National Laboratory (ORNL), AEA Technology (Harwell) and Lockheed Martin Corp.-Schenectady (LMS), which has influenced, or appeared in, ENDF/B-VI through Release 5. The discussion is restricted to the thermal and resolved resonance regions, apart from some questions about the unresolved region which still need investigation. The important role which benchmark testing has played will be touched on.

  8. Cross-sectional analysis of the chest and abdominal wall

    SciTech Connect

    Wechsler, R.J.

    1989-01-01

    This book covers the musculoskeletal envelope of the internal viscera as seen in cross section on computed tomographic (CT), magnetic resonance (MR), and ultrasound images. The contents proceed on the basis of anatomic areas, from the axilla and supraclavicular fossa, through the thoracic and abdominal wall and paraspinal musculature, to the glutei. Normal anatomic structure is described. Specific disease processes-such as inflammatory lymphadenitis, primary tumors, and vascular diseases-are covered.

  9. 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.

  10. 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)

  11. Stellar neutron capture cross sections of the Gd isotopes

    NASA Astrophysics Data System (ADS)

    Wisshak, K.; Voss, F.; Käppeler, F.; Guber, K.; Kazakov, L.; Kornilov, N.; Uhl, M.; Reffo, G.

    1995-11-01

    The neutron capture cross sections of 152Gd, 154Gd, 155Gd, 156Gd, 157Gd, and 158Gd were measured in the energy range from 3 to 225 keV at the Karlsruhe 3.75 MV Van de Graaff accelerator. Neutrons were produced via the 7Li(p,n)7Be reaction by bombarding metallic Li targets with a pulsed proton beam. Capture events were registered with the Karlsruhe 4? Barium Fluoride Detector, which was improved by replacing crystals with high ? background and by introducing a pierced crystal at zero degrees with respect to the beam axis. These changes resulted in a significantly increased efficiency for capture events. The main experimental problem was that the samples of the two s isotopes 152Gd and 154Gd showed only relatively low enrichment. Nevertheless, the spectroscopic quality of the BaF2 detector allowed evaluation of the corresponding corrections for isotopic impurities reliably. The cross section ratios could be determined with an overall uncertainty of typically 1%, an improvement by factors of five to ten compared to existing data. Severe discrepancies were found with respect to previous results. Maxwellian averaged neutron capture cross sections were calculated for thermal energies between kT=10 keV and 100 keV. The new stellar cross sections were used for an updated analysis of the s-process reaction flow in the mass region between samarium and gadolinium, which is characterized by branchings at 151Sm, 154Eu, and 155Eu. With the classical approach, the s-process temperature could be constrained corresponding to a range of thermal energies between kT=28 and 33 keV. The 152Gd production in low mass stars was found to depend strongly on the neutron freeze-out at the end of the helium shell burning episodes.

  12. Stellar neutron capture cross sections of the Gd isotopes

    Microsoft Academic Search

    K. Wisshak; F. Voss; F. Käppeler; L. Kazakov; N. Kornilov; G. Reffo

    1995-01-01

    The neutron capture cross sections of 152Gd, 154Gd, 155Gd, 156Gd, 157Gd, and 158Gd were measured in the energy range from 3 to 225 keV at the Karlsruhe 3.75 MV Van de Graaff accelerator. Neutrons were produced via the 7Li(p,n)7Be reaction by bombarding metallic Li targets with a pulsed proton beam. Capture events were registered with the Karlsruhe 4pi Barium Fluoride

  13. Stellar neutron capture cross sections of the Gd isotopes.

    NASA Astrophysics Data System (ADS)

    Wisshak, K.; Voss, F.; Käppeler, F.; Guber, K.; Kazakov, L.; Kornilov, N.; Uhl, M.; Reffo, G.

    1995-05-01

    The neutron capture cross sections of 152Gd, 154Gd, 155Gd, 156Gd, 157Gd, and 158Gd were measured in the energy range from 3 to 225 keV at the Karlsruhe 3.75 MV Van de Graaff accelerator. Neutrons were produced via the 7Li(p, n)7Be reaction by bombarding metallic Li targets with a pulsed proton beam. Capture events were registered with the Karlsruhe 4? Barium Fluoride Detector The main experimental problem was that the samples of the two s-only isotopes 152Gd and 154Gd showed only relatively low enrichment, but the spectroscopic quality of the BaF2 detector allowed to determine the resulting corrections for isotopic impurities reliably. The cross section ratios could be determined with an overall uncertainty of typically 1%, an improvement by factors of five to ten compared to existing data. Severe discrepancies were found with respect to previous results. Maxwellian averaged neutron capture cross sections were calculated for thermal energies between kT = 10 keV and 100 keV. The new stellar cross sections were used for an updated analysis of the s-process reaction flow in the mass region between samarium and gadolinium, which is characterized by branchings at 151Sm, 154Eu, and 155Eu. With the classical approach, the s-process temperature could be constrained corresponding to a range of thermal energies between kT - 28 keV and 33 keV. The 152Gd production in low mass stars was found to depend strongly on the neutron freeze-out at the end of the helium shell burning episodes.

  14. Cross section evaluation in the photodisintegration of152Sm isotope

    NASA Astrophysics Data System (ADS)

    Oprea, C.; Oprea, A.; Mihul, A.

    We have evaluated the cross section of the 152Sm(?, n)151Sm reaction in the frame of the Hauser - Feshbach formalism using the Talys computer codes as well as by using the computer codes written by the authors. The obtained results were compared with experimental data existing in the literature. The named computer codes allowed estimating the necessary penetrability coefficients with no approximations for charged and neutral particles emission in the exit channels.

  15. 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.

  16. A new approach to radar cross-section compact range

    NASA Astrophysics Data System (ADS)

    Harrison, T.

    1986-06-01

    A new concept in compact range antenna systems provides increased dynamic range and reflector efficiency of 50 to 70 percent. The technology is based on beam shaping concepts that have been applied to solve chamber coupling problems of present systems. The result is a substantial step forward in the test and design capabilities for ultra low radar cross-section (RCS) testing with available systems for targets up to 40 feet long.

  17. Measurement of Total Electron Scattering Cross Sections for SO2

    Microsoft Academic Search

    M. E. Johnston; J. A. Berger; J. P. Heggemeier; T. M. Klein

    1999-01-01

    In space sulphur dioxide (SO2) plays an important role in the atmospheres of Jupiter and Venus and interstellar clouds. On Earth it is responsible for acid rain and climate effects. In modeling these systems, electron impact data is needed. In this poster we present absolute total electron impact cross sections from 2 eV to 200 eV. The measurements were made

  18. Factors associated with inflammation markers, a cross-sectional analysis

    Microsoft Academic Search

    Tess V. Clendenen; Karen L. Koenig; Alan A. Arslan; Annekatrin Lukanova; Franco Berrino; Yian Gu; Goran Hallmans; Annika Idahl; Vittorio Krogh; Anna E. Lokshin; Eva Lundin; Paola Muti; Adele Marrangoni; Brian M. Nolen; Nina Ohlson; Roy E. Shore; Sabina Sieri; Anne Zeleniuch-Jacquotte

    Epidemiological studies have reported associations between circulating inflammation markers and risk of chronic diseases. It is of interest to examine whether risk factors for these diseases are associated with inflammation. We conducted a cross-sectional analysis to evaluate whether reproductive and lifestyle factors and circulating vitamin D were associated with inflammation markers, including C-reactive protein, cytokines (IL-1?, IL-2, IL-4, IL-5, IL-6,

  19. Inclusive charged particle cross sections in photoproduction at HERA

    Microsoft Academic Search

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

    1994-01-01

    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 pp collisions at comparable centre-of-mass energies &surd;Sgammap ~ &surd;Spp ~ 200GeV, and also harder than in

  20. Retrodeformable cross sections and Oak Ridge fault, Ventura basin, California

    Microsoft Academic Search

    R. S. Yeats; G. F. Huftile

    1988-01-01

    A retrodeformable (balanced) cross section is constructed such that stratified rocks are restored to their undeformed state without loss or gain of bed length or bed thickness. Ductile strata may be area-balanced if original thickness is known. Near Ventura, folds in Pliocene-Pleistocene turbidites and Miocene-early Pliocene shales (Rincon, Monterey, Sisquoc) overlie an unfolded competent Paleogene sequence. The basal decollement of

  1. Calculation of light nucleus reaction cross sections in Geant4

    E-print Network

    V. Uzhinsky

    2012-09-20

    Total reaction cross sections of light projectile nucleus (H-2, H-3, He-3 and He-4) interactions with nuclei are calculated using Geant4 models, and compared with experimental data. It is shown that the models give various predictions at low energies, in the region of the Coulomb barrier. "Shen model" (W.-Q. Shen et al., Nucl. Phys. {\\bf A491} (1989) 130) is identified as an improvement over other models.

  2. 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.

  3. 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.

  4. Coherent set of electron cross sections for argon

    NASA Astrophysics Data System (ADS)

    Alves, L. L.; Ferreira, C. M.

    2011-10-01

    This paper presents a coherent set of electron impact cross sections for argon (elastic momentum-transfer, inelastic for the excitation of 37 levels Ar(4s,4p,3d,5p,4d,6s) and ionization), which was recently uploaded onto the LXcat IST-Lisbon database. The cross section set was validated by comparing calculated swarm parameters (electron mobility and characteristic energy) and rate coefficients (Townsend ionization coefficient and direct + cascade excitation coefficients to the 4s and 4p states) with available experimental data, for E / N = 10-4 - 100 Td and Tg = 300, 77 K. The validation procedure involves the solution to the homogeneous two-term electron Boltzmann equation, resorting to three different solvers: (i) IST-Lisbon's (ii) BOLSIG+ (v1.2) with LXcat; (iii) BOLSIG+ (v1.23). The results obtained with these solvers are compared to evidence the importance of certain numerical features related with both the energy-grid (number of points, grid-type and maximum energy value) and the interpolation scheme adopted for the cross sections. In particular, the latter can cause a 6% variation on the values of swarm parameters at intermediate E/Ns.

  5. Summary of the Workshop on Neutron Cross Section Covariances

    SciTech Connect

    Smith, Donald L. [Argonne National Laboratory, 1710 Avenida del Mundo, Coronado, California 92118-3073 (United States)], E-mail: Donald.L.Smith@anl.gov

    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.

  6. A study of radar cross section measurement techniques

    NASA Astrophysics Data System (ADS)

    McDonald, Malcolm W.

    1986-11-01

    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.

  7. 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.

  8. Absolute photoionization cross section of the methyl radical.

    PubMed

    Loison, Jean-Christophe

    2010-06-17

    The absolute photoionization cross section of the methyl radical was determined relative to that of NO at photon energies of 10.54 eV using the CH(3) + NO(2) --> CH(3)O + NO reaction. Kinetics of this reaction was studied in a fast flow reactor coupled with VUV laser photoionization. Simulation of the kinetics of the decrease of the methyl signal and the corresponding increase of the NO signal (in combination with the NO absolute photoionization cross section determined by Watanabe (Watanabe, K. J. Chem. Phys. 1954, 22, 1564; Watanabe, K.; Matsunaga, F. M.; Sakai, H. Appl. Opt. 1967, 6, 391)), yields the absolute photoionization cross section of the methyl radical: sigma(CH(3))(10.54 eV) = 5.1 (1.2) x 10(-18) cm(2) (95% confidence interval). This result is in good agreement with the recently published measurements by Taatjes et al. (Taatjes, C. A.; Osborn, D. L.; Selby, T. M.; Meloni, G.; Fan, H.; Pratt, S. T. J. Phys. Chem. A 2008, 112, 9336) and by Gans et al. (Gans, B.; Mendes, L. A. V.; Boyé-Péronne, S.; Douin, S.; Garcia, G.; Soldi-Lose, H.; Cunha de Miranda, B. K.; Alcaraz, C.; Carrasco, N.; Pernot, P.; Gauyacq, D. J. Phys. Chem. A 2009, 114, 3237). PMID:20491459

  9. Activation Cross Sections Improvements needed for IFE Power Reactors Designs

    SciTech Connect

    Rodriguez, A; Cabellos, O; Sanz, J; FalQuina, R; Latkowski, J; Reyes, S

    2003-10-02

    Uncertainties in the prediction of the neutron induced long-lived activity in the natural elements from H to Bi due to activation cross section uncertainties are estimated assuming as neutron environment those of the HYLIFE-II and Sombrero vessel structures. The latest available activation cross section data are employed. The random variables used in the uncertainty analysis have been the concentration limits (CL's) corresponding to hands-on recycling, remote recycling and shallow land burial, quantities typically considered in ranking elements under waste management considerations. The CL standard value (CL{sub nom}), i.e. without uncertainties, is compared with the 95th percentile CL value (CL95). The results of the analysis are very helpful in assessing the quality of the current activation data for IFE applications, providing a rational basis for programmatic priority assignments for new cross sections measurements or evaluations. The HYLIFE-II results shown that a significant error is estimated in predicting the activation of several elements. The estimated errors in the Sombrero case are much less important.

  10. Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables

    E-print Network

    Dittmaier, S; Passarino, G; Tanaka, R; Baglio, J; Bolzoni, P; Boughezal, R; Brein, O; Collins-Tooth, C; Dawson, S; Dean, S; Denner, A; Farrington, S; Felcini, M; Flechl, M; de Florian, D; Forte, S; Grazzini, M; Hackstein, C; Hahn, T; Harlander, R; Hartonen, T; Heinemeyer, S; Huston, J; Kalinowski, A; Krämer, M; Krauss, F; Lee, J S; Lehti, S; Maltoni, F; Mazumdar, K; Moch, S -O; Mück, A; Mühlleitner, M; Nason, P; Neu, C; Oleari, C; Olsen, J; Palmer, S; Petriello, F; Piacquadio, G; Pilaftsis, A; Potter, C T; Puljak, I; Qian, J; Rebuzzi, D; Reina, L; Rzehak, H; Schumacher, M; Slavich, P; Spira, M; Stöckli, F; Thorne, R S; Acosta, M Vazquez; Vickey, T; Vicini, A; Wackeroth, D; Warsinsky, M; Weber, M; Weiglein, G; Weydert, C; Yu, J; Zaro, M; Zirke, T

    2011-01-01

    This Report summarizes the results of the first 10 months' activities of the LHC Higgs Cross Sections Working Group. The main goal of the working group was to present the status-of-art on Higgs Physics at the LHC integrating all new results that have appeared in the last few years. The Report is more than a mere collection of the proceedings of the general meetings. The subgroups have been working in different directions. An attempt has been made to present the first Report from these subgroups in a complete and homogeneous form. The subgroups' contributions correspondingly comprise the main parts of the Report. A significant amount of work has been performed in providing higher-order corrections to the Higgs-boson cross sections and pinning down the theoretical uncertainty of the Standard Model predictions. This Report comprises explicit numerical results on total cross sections, leaving the issues of event selection cuts and differential distributions to future publications. The subjects for further study a...

  11. Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables

    E-print Network

    LHC Higgs Cross Section Working Group; S. Dittmaier; C. Mariotti; G. Passarino; R. Tanaka; J. Baglio; P. Bolzoni; R. Boughezal; O. Brein; C. Collins-Tooth; S. Dawson; S. Dean; A. Denner; S. Farrington; M. Felcini; M. Flechl; D. de Florian; S. Forte; M. Grazzini; C. Hackstein; T. Hahn; R. Harlander; T. Hartonen; S. Heinemeyer; J. Huston; A. Kalinowski; M. Krämer; F. Krauss; J. S. Lee; S. Lehti; F. Maltoni; K. Mazumdar; S. -O. Moch; A. Mück; M. Mühlleitner; P. Nason; C. Neu; C. Oleari; J. Olsen; S. Palmer; F. Petriello; G. Piacquadio; A. Pilaftsis; C. T. Potter; I. Puljak; J. Qian; D. Rebuzzi; L. Reina; H. Rzehak; M. Schumacher; P. Slavich; M. Spira; F. Stöckli; R. S. Thorne; M. Vazquez Acosta; T. Vickey; A. Vicini; D. Wackeroth; M. Warsinsky; M. Weber; G. Weiglein; C. Weydert; J. Yu; M. Zaro; T. Zirke

    2011-05-20

    This Report summarizes the results of the first 10 months' activities of the LHC Higgs Cross Sections Working Group. The main goal of the working group was to present the status-of-art on Higgs Physics at the LHC integrating all new results that have appeared in the last few years. The Report is more than a mere collection of the proceedings of the general meetings. The subgroups have been working in different directions. An attempt has been made to present the first Report from these subgroups in a complete and homogeneous form. The subgroups' contributions correspondingly comprise the main parts of the Report. A significant amount of work has been performed in providing higher-order corrections to the Higgs-boson cross sections and pinning down the theoretical uncertainty of the Standard Model predictions. This Report comprises explicit numerical results on total cross sections, leaving the issues of event selection cuts and differential distributions to future publications. The subjects for further study are identified.

  12. Three Dimensional Cross-Sectional Properties From Bone Densitometry

    NASA Technical Reports Server (NTRS)

    Cleek, Tammy M.; Whalen, Robert T.; Dalton, Bonnie P. (Technical Monitor)

    2001-01-01

    Bone densitometry has previously been used to obtain cross-sectional properties of bone in a single scan plane. Using three non-coplanar scans, we have extended the method to obtain the principal area Moments of inertia and orientations of the principal axes at each cross-section along the length of the scan. Various 5 aluminum phantoms were used to examine scanner characteristics to develop the highest accuracy possible for in vitro non-invasive analysis of mass distribution. Factors considered included X-ray photon energy, initial scan orientation, the included angle of the 3 scans, and Imin/Imax ratios. Principal moments of inertia were accurate to within 3.1% and principal angles were within 1 deg. of the expected value for phantoms scanned with included angles of 60 deg. and 90 deg. at the higher X-ray photon energy. Low standard deviations in error also 10 indicate high precision of calculated measurements with these included angles. Accuracy and precision decreased slightly when the included angle was reduced to 30 deg. The method was then successfully applied to a pair of excised cadaveric tibiae. The accuracy and insensitivity of the algorithms to cross-sectional shape and changing isotropy (Imin/Imax) values when various included angles are used make this technique viable for future in vivo studies.

  13. Status of Nuclear Physics Cross Sections Models and Future Directions

    NASA Astrophysics Data System (ADS)

    Cucinotta, Francis A.; Tripathi, Ram; Kim, Myung-Hee Y.

    2012-07-01

    Exposures from the hazards of space radiation in deep space/long duration missions are very different from that of low earth orbit, and much needs to be learned about their effects. The overall situation is further augmented by the nonexistence of in vivo or in vitro data or studies about continuous long duration tissues exposure to radiation and concomitant biological uncertainties. All radiation protection and shielding transport and needed nuclear cross sections models so far have focused on radiation that goes through the shielding materials and are usually high energy physics models. From the perspective of exposure to astronauts, this exposure contributes to health risks. However, the very important radiation exposure where the radiation traverses through the astronauts and considerably slows down and/or even stops inside their body is less well studied. This kind of radiation contributes may be more biologically damaging than the radiation which just passes through because the ionizing power is highest as the particle stops in tissue. There is a clear need for improved nuclear physics cross sections models to described low energy collisions. Low energy physics significantly contributes to biological dose, risk assessments, and related uncertainty evaluations. In this report we will focus on the current status of these (mostly low energy) cross sections models and elaborate on future directions.

  14. Quantum Mechanical Determination of Rotational Energy Transfer Cross Sections.

    NASA Astrophysics Data System (ADS)

    Borer, William Shepherd

    Studies of the quantum mechanical determination of rotationally inelastic molecular collision rates are reported. A unified derivation of the coupled equations of scattering is given for four different quantum mechanical approximations. A new method for integrating the resulting coupled equations is studied and tested on a realistic potential surface. This method differs from conventional methods by not requiring the construction of a complete set of solutions to the second order differential equations in order to form a single solution satisfying the scattering boundary conditions. The method requires a computational effort proportional only to the square of the number of coupled equations as opposed to the cube which is characteristic of the conventional methods. In its primitive form, we find that the method is susceptible to several sources of numerical instability and does not always converge. Solutions to these problems are presented and discussed. A new bound on the error incurred through numerical integration of the coupled scattering equations is studied and applied to a model elastic potential. An optimal grid is found that minimizes the error measured by this bound. An improvement to the measure which weights more heavily those areas of the integration region for which the values of physical observables are expected to be more sensitive is made and studied. S matrix elements needed to exactly compute cross sections for angular momentum transfer in collisions between argon and hydrogen chloride have been computed using the studied method. Cross sections were constructed by forming the appropriate superpositions of computed S matrix elements. Cross sections for the width and shift of the j = 0 to 1 and j = 5 to 6 pure rotational absorption lines of HCl perturbed by Ar were computed at four different energies. The quantum mechanical cross sections agree well with previously computed counterparts obtained through a semiclassical treatment of the dynamics on the same potential surface as well as with experimental measurements on the same system. State to state cross sections between individual rotor states labelled by j and m where m is the quantum number for projection along a specified axis were also calculated. A distinct propensity to conserve m in inelastic collisions was found for one particular choice of quantization axis. This propensity is related to features of the potential surface and is consistent with similar propensities found in other molecular systems.

  15. Accurate Cross Sections for Excitation of Resonance Transitions in Atomic Oxygen

    NASA Technical Reports Server (NTRS)

    Tayal, S. S.

    2004-01-01

    Electron collision excitation cross sections for the resonance 2p(sup)4 (sup 3)P-2p(sup 3)3s (sup 3)S(sup 0), 2p(sup 4) (sup 3)P-2p(sup 3)3d (sup 3)D(sup 0), 2p4 (sup 3)P-2p(sup 3)3s (sup 3)D(sup 0), 2p(sup 4) (sup 3)P-2p(sup 3)3s (sup 3)P(sup 0) and 2p(sup 4) (sup 3)P-2s2p(sup 5) (sup 3)P(sup 0) transitions have been calculated by using the R matrix with a pseudostates approach for incident electron energies from near threshold to 100 eV. The excitation of these transition sgives rise to strong atomic oxygen emission features at 1304, 1027, 989, 878, and 792 Angstrom in the spectra of several planetary atmospheres. We included 22 spectroscopic bound and autoionizing states and 30 pseudostates in the close-coupling expansion. The target wave functions are chosen to properly account for the important correlation and relaxation effects. The effect of coupling to the continuum is included through the use of pseudostates. The contribution of the ionization continuum is significant for resonance transitions. Measured absolute direct excitation cross sections of 0 I are reported by experimental groups from the Jet Propulsion Laboratory and Johns Hopkins University. Good agreement is noted for the 2p(sup)4 (sup 3)P-2p(sup 3)3s (sup 3)S(sup 0) transition (lambda 1304 Ang) with measured cross sections from both groups that agree well with each other. There is disagreement between experiments for other transitions. Our results support the measured cross sections from the Johns Hopkins University for the 2p(sup 4) (sup 3)P-2p(sup 3)3d (sup 3)D(sup 0) and 2p4 (sup 3)P-2p(sup 3)3s (sup 3)D(sup 0) transitions, while for the 2p4 (sup 3)P-2p(sup 3)3s (sup 3)D(sup 0) transition the agreement is switched to the measured cross sections from the Jet Propulsion Laboratory.

  16. 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.

  17. Handbook of LHC Higgs Cross Sections: 3. Higgs Properties Report of the LHC Higgs Cross Section Working Group

    E-print Network

    Mariotti, C; Passarino, G; Tanaka, R; Andersen, J R; Artoisenet, P; Bagnaschi, E A; Banfi, A; Becher, T; Bernlochner, F U; Bolognesi, S; Bolzoni, P; Boughezal, R; Buarque, D; Campbell, J; Caola, F; Carena, M; Cascioli, F; Chanon, N; Cheng, T; Choi, S Y; David, A; de Aquino, P; Degrassi, G; Del Re, D; Denner, A; van Deurzen, H; Diglio, S; Di Micco, B; Di Nardo, R; Dittmaier, S; Dührssen, M; Ellis, R K; Ferrera, G; Fidanza, N; Flechl, M; de Florian, D; Forte, S; Frederix, R; Frixione, S; Gangal, S; Gao, Y; Garzelli, M V; Gillberg, D; Govoni, P; Grazzini, M; Greiner, N; Griffiths, J; Gritsan, A V; Grojean, C; Hall, D C; Hays, C; Harlander, R; Hernandez-Pinto, R; Höche, S; Huston, J; Jubb, T; Kadastik, M; Kallweit, S; Kardos, A; Kashif, L; Kauer, N; Kim, H; Klees, R; Krämer, M; Krauss, F; Laureys, A; Laurila, S; Lehti, S; Li, Q; Liebler, S; Liu, X; Logan, E; Luisoni, G; Malberti, M; Maltoni, F; Mawatari, K; Maierhoefer, F; Mantler, H; Martin, S; Mastrolia, P; Mattelaer, O; Mazzitelli, J; Mellado, B; Melnikov, K; Meridiani, P; Miller, D J; Mirabella, E; Moch, S O; Monni, P; Moretti, N; Mück, A; Mühlleitner, M; Musella, P; Nason, P; Neu, C; Neubert, M; Oleari, C; Olsen, J; Ossola, G; Peraro, T; Peters, K; Petriello, F; Piacquadio, G; Potter, C T; Pozzorini, S; Prokofiev, K; Puljak, I; Rauch, M; Rebuzzi, D; Reina, L; Rietkerk, R; Rizzi, A; Rotstein-Habarnau, Y; Salam, G P; Sborlini, G; Schissler, F; Schönherr, M; Schulze, M; Schumacher, M; Siegert, F; Slavich, P; Smillie, J M; Stål, O; von Soden-Fraunhofen, J F; Spira, M; Stewart, I W; Tackmann, F J; Taylor, P T E; Tommasini, D; Thompson, J; Thorne, R S; Torrielli, P; Tramontano, F; Tran, N V; Trócsányi, Z; Ubiali, M; Vazquez Acosta, M; Vickey, T; Vicini, A; Waalewijn, W J; Wackeroth, D; Wagner, C; Walsh, J R; Wang, J; Weiglein, G; Whitbeck, A; Williams, C; Yu, J; Zanderighi, G; Zanetti, M; Zaro, M; Zerwas, P M; Zhang, C; Zirke, T J E; Zuberi, S

    2013-01-01

    This Report summarizes the results of the activities in 2012 and the first half of 2013 of the LHC Higgs Cross Section Working Group. The main goal of the working group was to present the state of the art of Higgs Physics at the LHC, integrating all new results that have appeared in the last few years. This report follows the first working group report Handbook of LHC Higgs Cross Sections: 1. Inclusive Observables (CERN-2011-002) and the second working group report Handbook of LHC Higgs Cross Sections: 2. Differential Distributions (CERN-2012-002). After the discovery of a Higgs boson at the LHC in mid-2012 this report focuses on refined prediction of Standard Model (SM) Higgs phenomenology around the experimentally observed value of 125-126 GeV, refined predictions for heavy SM-like Higgs bosons as well as predictions in the Minimal Supersymmetric Standard Model and first steps to go beyond these models. The other main focus is on the extraction of the characteristics and properties of the newly discovered p...

  18. Triple-differential cross sections for inner-shell electron-impact ionization of carbon

    SciTech Connect

    Jia Xiangfu; Liu Minghai; Sun Shiyan; Wu Yuan [College of Physics and Information Engineering, Institute of Modern Physics, Shanxi Teachers University, Linfen, Shanxi 041004 (China)

    2004-06-01

    Triple-differential cross sections (TDCS) have been calculated for the K-shell ionization of carbon atom by fast electron impact for highly asymmetric kinematics. In the present calculation the three Coulomb two-body interaction, the dynamic screening modification of these interactions and the correlation in the final channel, the screening effect of the multielectron target, and the distortion of Coulomb force in the initial channel have been taken into account. Results are compared with the relative measurement performed on the C{sub 2}H{sub 2} molecule as target. The present TDCS is found to be in better accord with experiment.

  19. Calculation of the photoionization cross sections for the potassium and the bromine atoms by using the time-dependent local spin density approximation

    Microsoft Academic Search

    A. S. Choe; Byungduk Yoo; Jongmin Lee

    1993-01-01

    The density functional approach to local field is extended to a spin-polarized finite electronic system. The time-varying local field, which is dependent on the spin components of electrons, incorporates the polarization-type many-body effects of electronic correlations into the photoionization cross section. To examine the spin-dependent local field effects, the photoionization cross sections of the potassium and the bromine atom are

  20. Evaporation residue, fission cross sections, and linear momentum transfer for 14N induced reactions from 35A to 155A MeV

    Microsoft Academic Search

    A. A. Sonzogni; A. Elmaani; C. Hyde-Wright; W. Jiang; D. Prindle; R. Vandenbosch; J. Dinius; G. Cron; D. Bowman; C. K. Gelbke; W. Hsi; W. G. Lynch; C. Montoya; G. Peaslee; C. Schwarz; M. B. Tsang; C. Williams; R. Desouza; D. Fox; T. Moore

    1996-01-01

    Differential cross sections for evaporation residues and fission fragments for 35A, 100A, 130A and 155A MeV 14N on targets ranging from 154Sm to 197Au have been measured. The angle-integrated cross sections are larger than what might be expected. The fission fragment-fission fragment folding angle correlations for 35A, 100A MeV 14N and 25A MeV 16O on similar targets were also measured.