262 research outputs found

    Particle multiplicities at LHC and deviations from limiting fragmentation

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    The pseudorapidity density of charged particles produced at LHC collisions are predicted by using two complementary production mechanisms with a set of consistent integrated and unintegrated parton distributions. We discuss the limiting fragmentation hypothesis and its possible violation, and we compare our model with other partonic models.Comment: 26 pages, 27 figures, Accepted for publication in Phys. Rev.

    Axion Cosmology Revisited

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    The misalignment mechanism for axion production depends on the temperature-dependent axion mass. The latter has recently been determined within the interacting instanton liquid model (IILM), and provides for the first time a well-motivated axion mass for all temperatures. We reexamine the constraints placed on the axion parameter space in the light of this new mass function. We find an accurate and updated constraint f_a \le 2.8(\pm2)\times 10^{11}\units{GeV} or m_a \ge 21(\pm2) \units{\mu eV} from the misalignment mechanism in the classic axion window (thermal scenario). However, this is superseded by axion string radiation which leads to f_a \lesssim 3.2^{+4}_{-2} \times 10^{10} \units{GeV} or m_a \gtrsim 0.20 ^{+0.2}_{-0.1} \units{meV}. In this analysis, we take care to precisely compute the effective degrees of freedom and, to fill a gap in the literature, we present accurate fitting formulas. We solve the evolution equations exactly, and find that analytic results used to date generally underestimate the full numerical solution by a factor 2-3. In the inflationary scenario, axions induce isocurvature fluctuations and constrain the allowed inflationary scale HIH_I. Taking anharmonic effects into account, we show that these bounds are actually weaker than previously computed. Considering the fine-tuning issue of the misalignment angle in the whole of the anthropic window, we derive new bounds which open up the inflationary window near θaπ\theta_a \to \pi. In particular, we find that inflationary dark matter axions can have masses as high as 0.01--1\units{meV}, covering the whole thermal axion range, with values of HIH_I up to 10910^9GeV. Quantum fluctuations during inflation exclude dominant dark matter axions with masses above ma1m_a\lesssim 1meV.Comment: 42 pages, 12 figures, version as accepted by Phys.Rev.

    MD1 HEALTH ECONOMIC ANALYSIS OF CONTINUOUS SUBCUTANEOUS INSULIN INFUSION COMPARED TO MULTIPLE DAILY INJECTIONS FOR THE TREATMENT OF TYPE 1 DIABETES IN POLAND

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    LCG MCDB -- a Knowledgebase of Monte Carlo Simulated Events

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    In this paper we report on LCG Monte Carlo Data Base (MCDB) and software which has been developed to operate MCDB. The main purpose of the LCG MCDB project is to provide a storage and documentation system for sophisticated event samples simulated for the LHC collaborations by experts. In many cases, the modern Monte Carlo simulation of physical processes requires expert knowledge in Monte Carlo generators or significant amount of CPU time to produce the events. MCDB is a knowledgebase mainly dedicated to accumulate simulated events of this type. The main motivation behind LCG MCDB is to make the sophisticated MC event samples available for various physical groups. All the data from MCDB is accessible in several convenient ways. LCG MCDB is being developed within the CERN LCG Application Area Simulation project

    Molecular Phylogentic Analysis of Marine Polychaeta and Crassostrea rivularis

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    底栖生物在海洋生态系统中起着极其重要的作用,部分底栖生物也是重要的海洋经济物种。同时因为海洋底栖动物活动性小、地区性强,可以较好地反映水质和地质的污染状况,在海洋污染生物学指标中具有特别重要的意义。因此对底栖生物进行正确的分类和系统发育学研究是十分必要的。过去对底栖生物的分类主要根据形态来划分,但是随着科学的发展传统形态学越来越遇到一些难以克服的障碍,如趋同进化的问题。另外用形态特征定义一个分类阶元,就必须对标本的完整性、性别、生长阶段有严格的要求,因此对于一些特殊条件下取得的很难保持完整的形态的标本来说,进行形态学的鉴定尤其困难。现代分子生物学的发展。使我们可以利用核酸、蛋白质等生物大分子的...Marine benthos play a very important role in the ecology of marine environment. Lots of the animals are also important economic marine species. Meanwhile, because they are characterized as narrow active and special territory distribution, they can be used to indicate the quality of water and the polluted condition of sediments, which is an important part of the biologic indication of marine pollut...学位:理学硕士院系专业:生命科学学院生物学系_生物化学与分子生物学学号:20012605

    The Price of WMAP Inflation in Supergravity

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    The three-year data from WMAP are in stunning agreement with the simplest possible quadratic potential for chaotic inflation, as well as with new or symmetry-breaking inflation. We investigate the possibilities for incorporating these potentials within supergravity, particularly of the no-scale type that is motivated by string theory. Models with inflation driven by the matter sector may be constructed in no-scale supergravity, if the moduli are assumed to be stabilised by some higher-scale dynamics and at the expense of some fine-tuning. We discuss specific scenarios for stabilising the moduli via either D- or F-terms in the effective potential, and survey possible inflationary models in the presence of D-term stabilisation.Comment: 15 pages, 6 figures, plain Late

    The HQET/NRQCD Lagrangian to order alpha/m^3

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    The HQET/NRQCD Lagrangian is computed to order alpha/m^3. The computation is performed using dimensional regularization to regulate the ultraviolet and infrared divergences. The results are consistent with reparametrization invariance to order 1/m^3. Some subtleties in the matching conditions for NRQCD are discussed.Comment: Two terms added to Lagrangian. Explicit value of G^3 coefficient given. Some references added, and TeX problems fixed. (18 pages, uses revtex

    Tools for Deconstructing Gauge Theories in AdS5

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    We employ analytical methods to study deconstruction of 5D gauge theories in the AdS5 background. We demonstrate that using the so-called q-Bessel functions allows a quantitative analysis of the deconstructed setup. Our study clarifies the relation of deconstruction with 5D warped theories.Comment: 30 pages; v2: several refinements, references adde

    Neutrino Unification

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    Present neutrino data are consistent with neutrino masses arising from a common seed at some ``neutrino unification'' scale MXM_X. Such a simple theoretical ansatz naturally leads to quasi-degenerate neutrinos that could lie in the electron-volt range with neutrino mass splittings induced by renormalization effects associated with supersymmetric thresholds. In such a scheme the leptonic analogue of the Cabibbo angle θ\theta_{\odot} describing solar neutrino oscillations is nearly maximal. Its exact value is correlated with the smallness of θreactor\theta_{reactor}. These features agree both with latest data on the solar neutrino spectra and with the reactor neutrino data. The two leading mass-eigenstate neutrinos present in \ne form a pseudo-Dirac neutrino, avoiding conflict with neutrinoless double beta decay.Comment: RevTex format, 2 figures, 4 pages, a few new references, no other important change, figures unchanged, version to be published in PR
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