10,960 research outputs found

    Global NLO Analysis of Nuclear Parton Distribution Functions

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    Nuclear parton distribution functions (NPDFs) are determined by a global analysis of experimental measurements on structure-function ratios F_2^A/F_2^{A'} and Drell-Yan cross section ratios \sigma_{DY}^A/\sigma_{DY}^{A'}, and their uncertainties are estimated by the Hessian method. The NPDFs are obtained in both leading order (LO) and next-to-leading order (NLO) of \alpha_s. As a result, valence-quark distributions are relatively well determined, whereas antiquark distributions at x>0.2 and gluon distributions in the whole x region have large uncertainties. The NLO uncertainties are slightly smaller than the LO ones; however, such a NLO improvement is not as significant as the nucleonic case.Comment: 3 pages, LaTeX, 4 eps files, to be published in the AIP proceedings of the 9th International Workshop on Neutrino Factories, Superbeams and Betabeams (NuFact07), Okayama, Japan, August 6 - 11, 2007. A code for calculating our nuclear parton distribution functions and their uncertainties can be obtained from http://research.kek.jp/people/kumanos/nuclp.htm

    Study of fusion reactions of light nuclei at low energies using complex nucleon-nucleus potential function

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    Nuclear fusion reactions, at energies, far below the Coulomb barrier play a significant role in the synthesis of light elements in the primordial nucleosynthesis as well as in the interior of compact stellar objects. Many different kinds of nuclear reactions are occurring simultaneously inside the stellar core depending upon the density and temperature conditions of the nuclear plasma along with other relevant parameters of these stars. Nuclear fusion reactions in the energy range (EE\sim 1 eV to few keV) can be explained successfully by quantum mechanical tunneling through the mutual Coulomb barrier of interacting nuclei. The measurement of the cross-sections at extremely low energy is quite difficult because of the larger width of the Coulomb barrier, which results in a very small value of the reaction cross-section. Hence, any improvement in the data on astrophysical S-factors for the light nuclei fusion may give a better picture of the elemental abundance in nucleosynthesis. In this work, we have theoretically investigated the energy dependence of fusion cross-sections and astrophysical S-factors for fusion reaction of light nuclei like D-D and p-11^{11}B using complex Gaussian nuclear potential with adjustable depth and range parameters plus the mutual Coulomb interaction of the interacting nuclei. Numerical computation of the observables is done in the framework of the selective resonant tunneling model approach. The results of our calculation are compared with those found in the literature.Comment: 13 Pages, 5 Figure

    Debranching improves morpho - physiological characters, fruit quality and yield of tomato

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    Farmers are commercially cultivated tomato with different levels of shoot pruning but this production practice has not been defined clearly. The experiment was conducted under sub-tropical condition to assess the effect of different levels of debranching on morpho-physiological, reproductive and yield contributing characters in determinate tomato cultivar cv. Binatomato-5. The debranching levels were: i) control, ii) only mainstem (MS), iii) MS with 2 branches, iv) MS with 3 branches and v) MS with 4 branches. Based on recommended spacing (50 cm × 50 cm), the higher fruit yield plant⁻¹ as well as ruit yield per hectare were observed in more branch bearing plants of the treatment control (MS with 5-6 branches), MS with 3 branches and MS with 4 branches due to production of higher number of fruits plant⁻¹ with being the highest in MS with 3 branches due to increase fruit size. The lowest fruit yield per plant as well as per hectare was observed in uniculm plants due to lower number of fruits per plant. This study suggests that plants that have MS with three branches may be recommended for commercial cultivation of tomato under sub-tropical condition

    COPING WITH NATURAL DISASTERS: A CROSS-SECTIONAL STUDY WITH PEOPLE WITH DISABILITIES IN THE COASTAL ZONE OF BANGLADESH

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    Coastal zone of Bangladesh is highly vulnerable to different nature induced hydrological and climatological disasters. Disaster disproportionately affects a different group of populations. Among them, “people with disabilities” (PWDs) regardless of their gender face severe challenges in a disaster situation. The response mechanisms of disabled people in disaster context are also different. This paper aimed to examine the coping strategies of PWDs with a natural disaster in the coastal zone of Bangladesh. We conducted a cross-sectional survey among 150 disabled people from Mongla sub-district, Rampal sub-district and Sharankhola sub-district of Bagerhat district. Most of the respondents (60%) did not receive any training on disaster preparedness but the majority of them (88%) had knowledge on the location of the nearest disaster shelters and took shelter at government listed centers before or during the disaster. They were not satisfied with the facilities and services of those disaster shelters. Nearly two-thirds (64%) of the respondents received disaster forecasting through electronic media. More than one-fifth of the respondents (22.7%) changed their occupations after a major disaster and one-fourth of the respondents (26.7%) were displaced or migrated from their original house as a consequence of the disaster. Although disabled people are one of the most vulnerable groups in disaster milieu, they have drawn limited attention by the policymakers, academicians and development organizations. This paper provides few coping strategies of disabled people that will help the policymakers to think and take disabled friendly measures in policy documents and development interventions

    Initial report from the ICFA Neutrino Panel

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    In July 2013 ICFA established the Neutrino Panel with the mandate "To promote international cooperation in the development of the accelerator-based neutrino-oscillation program and to promote international collaboration in the development a neutrino factory as a future intense source of neutrinos for particle physics experiments". This, the Panel's Initial Report, presents the conclusions drawn by the Panel from three regional "Town Meetings" that took place between November 2013 and February 2014. After a brief introduction and a short summary of the status of the knowledge of the oscillation parameters, the report summarises the approved programme and identifies opportunities for the development of the field. In its conclusions, the Panel recognises that to maximise the discovery potential of the accelerator-based neutrino-oscillation programme it will be essential to exploit the infrastructures that exist at CERN, FNAL and J-PARC and the expertise and resources that reside in laboratories and institutes around the world. Therefore, in its second year, the Panel will consult with the accelerator-based neutrino-oscillation community and its stakeholders to: develop a road-map for the future accelerator-based neutrino-oscillation programme that exploits the ambitions articulated at CERN, FNAL and J-PARC and includes the programme of measurement and test-beam exposure necessary to ensure the programme is able to realise its potential; develop a proposal for a coordinated "Neutrino RD" programme, the accelerator and detector R&D programme required to underpin the next generation of experiments; and to explore the opportunities for the international collaboration necessary to realise the Neutrino Factory.Comment: ICFA Neutrino Panel 2014(01

    On the complementarity of Hyper-K and LBNF

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    The next generation of long-baseline experiments is being designed to make a substantial step in the precision of measurements of neutrino-oscillation probabilities. Two qualitatively different proposals, Hyper-K and LBNF, are being considered for approval. This document outlines the complimentarity between Hyper-K and LBNF.Comment: 5 pager
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