988 resultados para Virial Masses


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We attempt a comprehensive analysis of the low lying charm meson states which present several puzzles, including the poor determination of masses of several non-strange excited mesons. We use the well-determined masses of the ground states and the strange first excited states to 'predict' the mass of the non-strange first excited state in the framework of heavy hadron chiral perturbation theory, an approach that is complementary to the well-known analysis of Mehen and Springer. This approach points to values for the masses of these states that are smaller than the experimental determinations. We provide a critical assessment of these mass measurements and point out the need for new experimental information. (c) 2007 Elsevier B.V. All rights reserved.

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Fugacity coefficients and isothermal changes of enthalpy have been calculated and reported. The calculations cover a temperature range of 0° to 75°C. up to gas densities of 1.0 gram per cc. The generalized Benedict-Webb-Rubin constants evaluated from generalized PVT relations is found to predict the experimental data with an over-all absolute deviation of 3.1%. Second virial coefficients and potential energy parameters for Lennard-Jones (12-6) potential energy function are reported also.

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This study is a pragmatic description of the evolution of the genre of English witchcraft pamphlets from the mid-sixteenth century to the end of the seventeenth century. Witchcraft pamphlets were produced for a new kind of readership semi-literate, uneducated masses and the central hypothesis of this study is that publishing for the masses entailed rethinking the ways of writing and printing texts. Analysis of the use of typographical variation and illustrations indicates how printers and publishers catered to the tastes and expectations of this new audience. Analysis of the language of witchcraft pamphlets shows how pamphlet writers took into account the new readership by transforming formal written source materials trial proceedings into more immediate ways of writing. The material for this study comes from the Corpus of Early Modern English Witchcraft Pamphlets, which has been compiled by the author. The multidisciplinary analysis incorporates both visual and linguistic aspects of the texts, with methodologies and theoretical insights adopted eclectically from historical pragmatics, genre studies, book history, corpus linguistics, systemic functional linguistics and cognitive psychology. The findings are anchored in the socio-historical context of early modern publishing, reading, literacy and witchcraft beliefs. The study shows not only how consideration of a new audience by both authors and printers influenced the development of a genre, but also the value of combining visual and linguistic features in pragmatic analyses of texts.

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Lepton masses and mixing angles via localization of 5-dimensional fields in the bulk are revisited in the context of Randall-Sundrum models. The Higgs is assumed to be localized on the IR brane. Three cases for neutrino masses are considered: (a) The higher-dimensional neutrino mass operator (LH.LH), (b) Dirac masses, and (c) Type I seesaw with bulk Majorana mass terms. Neutrino masses and mixing as well as charged lepton masses are fit in the first two cases using chi(2) minimization for the bulk mass parameters, while varying the O(1) Yukawa couplings between 0.1 and 4. Lepton flavor violation is studied for all the three cases. It is shown that large negative bulk mass parameters are required for the right-handed fields to fit the data in the LH.LH case. This case is characterized by a very large Kaluza-Klein (KK) spectrum and relatively weak flavor-violating constraints at leading order. The zero modes for the charged singlets are composite in this case, and their corresponding effective 4-dimensional Yukawa couplings to the KK modes could be large. For the Dirac case, good fits can be obtained for the bulk mass parameters, c(i), lying between 0 and 1. However, most of the ``best-fit regions'' are ruled out from flavor-violating constraints. In the bulk Majorana terms case, we have solved the profile equations numerically. We give example points for inverted hierarchy and normal hierarchy of neutrino masses. Lepton flavor violating rates are large for these points. We then discuss various minimal flavor violation schemes for Dirac and bulk Majorana cases. In the Dirac case with minimal-flavor-violation hypothesis, it is possible to simultaneously fit leptonic masses and mixing angles and alleviate lepton flavor violating constraints for KK modes with masses of around 3 TeV. Similar examples are also provided in the Majorana case.

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Planck scale lepton number violation is an interesting and natural possibility to explain nonzero neutrino masses. We consider such operators in the context of Randall-Sundrum (RS1) scenarios. Implementation of this scenario with a single Higgs localized on the IR brane (standard RS1) is not phenomenologically viable as they lead to inconsistencies in the charged lepton mass fits. In this paper we propose a setup with two Higgs doublets. We present a detailed numerical analysis of the fits to fermion masses and mixing angles. This model solves the issues regarding the fermion mass fits but solutions with consistent electroweak symmetry breaking are highly fine-tuned. A simple resolution is to consider supersymmetry in the bulk and a detailed discussion of which is provided. Constraints from flavor are found to be strong and minimal flavor violation (MFV) is imposed to alleviate them.

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The complete proof of the virial theorem in refined Thomas-Fermi-Dirac theory for all electrons of an atom in a solid is given.

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本文在提出广义Gauss定理的思路下,提出了广义Stokes定理和一个推广Virial定理的新方法,后者应用于天体磁流体力学和引力平衡问题时得到的结果有:(1)气体具有运动时的平衡系统的判据,(2)磁场对气团形态的影响。应用于实验室等离子体平衡问题时,其结果有:(1)包围在气体中孤立磁场的特性,(2)发现内包无力场必须外包一有力场,(3)无力场的形态,应用于Tokmak等离子体环时的结果有:(1)环的胖瘦对环表面磁压的影响,(2)两个外加磁场分量分别和气压、环的胖瘦,截面形态、环电流分布和逆磁或顺磁的平衡关系,搞清楚了外加磁场约束等离子体总体平衡的物理机制。

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From 1977 to 1980, several research cruises were carried out in the coastal waters of Mozambique to collect oceanographic data. The distribution of hydrographic and bathythermograph stations is given. The water masses and circulation were mapped and wind data gathered.

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The hydrographic structure of the northern Red Sea indicated that, the surface waters of temperature around 22°C, salinity of 40.1OO%o and dt = 28.1 might sink to depths between 400-500 m by convective overturn, contributing to the formation of the mid-deep Red Sea waters. Below the 500 db depth down to the bottom the water column is stable. The geostrophic circulation clearly indicated an inflow of water from the Red Sea towards NNW, along the main axis of the sea. Arriving at the northern edge of the sea, it sends a branch in the Gulf of Aqaba, turns to the west, and sends another branch to the Gulf of Suez, but its main mass reaches the African coast where it sets southward along this coast. A large cyclonic gyre centered near 27 deg 30'N and 34 deg l0'E is detected at the head of the Red Sea deep waters. The effect of the outflow of the bottom water of the Gulf of Suez on the formation of the deep water of the Red Sea is limited.

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A systematic study of the pi(-)/pi(+) ratio in heavy-ion collisions with the same neutron/proton ratio but different masses can help single out effects of the nuclear mean field on pion production. Based on simulations using the IBUU04 transport model, it is found that the pi(-)/pi(+) ratio in head-on collisions of Ca-48 + Ca-48, Sn-124 + Sn-124, and Au-197 + Au-197 at beam energies from 0.25 to 0.6 GeV/nucleon increases with increasing the system size or decreasing the beam energies. A comprehensive analysis of the dynamical isospin fractionation and the pi(-)/pi(+) ratio as well as their time evolution and spatial distributions demonstrates clearly that the pi(-)/pi(+) ratio is an effective probe of the high-density behavior of the nuclear symmetry energy.

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We introduce and summary our research progress on the effective masses of K meson in dense nuclear matter.