109,548 research outputs found

    Probing the hadronic phase with resonances of different lifetimes in Pb-Pb collisions with ALICE

    Get PDF
    The ALICE experiment has measured the production of a rich set of hadronic resonances, such as ρ(770)0\rho(770)^{0}, K(892)0{\rm K}^{\ast}(892)^{0}, ϕ\phi(1020), Σ±\Sigma^{\pm}(1385), Λ(1520)\Lambda(1520) and Ξ0\Xi^{\ast 0} in pp, p-Pb and Pb-Pb collisions at various energies at the LHC. A comprehensive overview and the latest results are presented in this paper. Special focus is given to the role of hadronic resonances for the study of final-state effects in high-energy collisions. In particular, the measurement of resonance production in heavy-ion collisions has the capability to provide insight into the existence of a prolonged hadronic phase after hadronisation. The observation of the suppression of the production of Λ(1520)\Lambda(1520) resonance in central Pb-Pb collisions at sNN\sqrt{s_{\rm NN}} = 2.76 TeV adds further support to the existence of such a dense hadronic phase, as already evidenced by the ratios K(892)0{\rm K}^{\ast}(892)^{0}/K{\rm K} and ρ(770)0\rho(770)^{0}/π\pi.Comment: 4 pages, 3 figures, 17th International Conference on Strangeness in Quark Matter (SQM 2017

    Non-Gaussianity of Inflationary Gravitational Waves from the Field Equation

    Full text link
    We demonstrate equivalence of the in-in formalism and Green's function method for calculating the bispectrum of primordial gravitational waves generated by vacuum fluctuations of the metric. The tree-level bispectrum from the field equation, BhB_h, agrees with the results obtained previously using the in-in formalism exactly. Characterising non-Gaussianity of the fluctuations using the ratio Bh/Ph2B_h/P^2_h in the equilateral configuration, where PhP_h is the power spectrum of scale-invariant gravitational waves, we show that it is much weaker than in models with spectator gauge fields. We also calculate the tree-level bispectrum of two right-handed and one left-handed gravitational wave using Green's function, reproducing the results from in-in formalism, and show that it can be as large as the bispectrum of three right-handed gravitational waves.Comment: 17 pages, 2 figures; comments welcom

    Nutrigenomics: Using Sulforaphane Consumption as a Mechanism to Prevent Cardiovascular Disease through Epigenetic Regulation

    Get PDF
    Cardiovascular disease is the leading cause of death in the United States. Diet composition and reduced expression of the transcription factor Nrf2 are both possible factors contributing to cardiovascular disease. As vitamin supplementation grows in scope and popularity, it is becoming common to replace vegetable consumption with multivitamins. The purpose of this research was to investigate how sulforaphane, an isothiocyanate found in its greatest quantities in broccoli, prevents cardiovascular disease through epigenetic regulation in order to promote the understanding that vitamin supplementation does not adequately replace the health benefits of phytonutrients found in vegetables. In order to investigate sulforaphane’s ability to prevent cardiovascular disease through epigenetic regulation, I studied scholarly journal articles that focused on experiments involving sulforaphane-induced activation of Nrf2 and the effects of Nrf2 activation such as up-regulation of antioxidant genes and phase II enzymes. Additionally, I studied articles examining sulforaphane-induced reductions in blood pressure and elimination of cardiac dysfunctions such as cardiac hypertrophy and decreased fractional shortening with the goal of identifying Nrf2 activation as the underlying mechanism. The results showed that up-regulation of antioxidant genes, signaling of phase II enzymes, lowered blood pressure, and elimination of cardiac dysfunctions were all a result of sulforaphane-induced activation of Nrf2. These results indicate that people who may be at risk for cardiovascular disease could benefit from including broccoli in their diet rather than using vitamin and mineral supplementation to replace vegetables that provide valuable phytonutrients.https://scholarscompass.vcu.edu/uresposters/1284/thumbnail.jp

    Samplers and Extractors for Unbounded Functions

    Get PDF
    Blasiok (SODA\u2718) recently introduced the notion of a subgaussian sampler, defined as an averaging sampler for approximating the mean of functions f from {0,1}^m to the real numbers such that f(U_m) has subgaussian tails, and asked for explicit constructions. In this work, we give the first explicit constructions of subgaussian samplers (and in fact averaging samplers for the broader class of subexponential functions) that match the best known constructions of averaging samplers for [0,1]-bounded functions in the regime of parameters where the approximation error epsilon and failure probability delta are subconstant. Our constructions are established via an extension of the standard notion of randomness extractor (Nisan and Zuckerman, JCSS\u2796) where the error is measured by an arbitrary divergence rather than total variation distance, and a generalization of Zuckerman\u27s equivalence (Random Struct. Alg.\u2797) between extractors and samplers. We believe that the framework we develop, and specifically the notion of an extractor for the Kullback-Leibler (KL) divergence, are of independent interest. In particular, KL-extractors are stronger than both standard extractors and subgaussian samplers, but we show that they exist with essentially the same parameters (constructively and non-constructively) as standard extractors

    Deformations of overconvergent isocrystals on the projective line

    Full text link
    Let kk be a perfect field of positive characteristic and ZZ an effective Cartier divisor in the projective line over kk with complement UU. In this note, we establish some results about the formal deformation theory of overconvergent isocrystals on UU with fixed "local monodromy" along ZZ. En route, we show that a Hochschild cochain complex governs deformations of a module over an arbitrary associative algebra. We also relate this Hochschild cochain complex to a de Rham complex in order to understand the deformation theory of a differential module over a differential ring.Comment: 59 pages; fixed typos, improved exposition; comments welcome

    Coefficient estimates for some classes of functions associated with qq-function theory

    Full text link
    In this paper, for every q(0,1)q\in(0,1), we obtain the Herglotz representation theorem and discuss the Bieberbach type problem for the class of qq-convex functions of order α,0α<1\alpha, 0\le\alpha<1. In addition, we discuss the Fekete-szeg\"o problem and the Hankel determinant problem for the class of qq-starlike functions, leading to couple of conjectures for the class of qq-starlike functions of order α,0α<1\alpha, 0\le\alpha<1.Comment: 12 page

    Asymmetric nuclear matter and neutron-skin in extended relativistic mean field model

    Full text link
    The density dependence of the symmetry energy, instrumental in understanding the behaviour of the asymmetric nuclear matter, is investigated within the extended relativistic mean field (ERMF) model which includes the contributions from the self and mixed interaction terms for the scalar-isoscalar (σ\sigma), vector-isoscalar (ω\omega) and vector-isovector (ρ\rho) mesons upto the quartic order. Each of the 26 different parameterizations of the ERMF model employed are compatible with the bulk properties of the finite nuclei. The behaviour of the symmetry energy for several parameter sets are found to be consistent with the empirical constraints on them as extracted from the analyses of the isospin diffusion data. The neutron-skin thickness in the 208^{208}Pb nucleus for these parameter sets of the ERMF model lie in the range of 0.200.24\sim 0.20 - 0.24 fm which is in harmony with the ones predicted by the Skyrme Hartree-Fock model. We also investigate the role of various mixed interaction terms which are crucial for the density dependence of the symmetry energy.Comment: 14 pages, 4 figures, Physical Review C (in press
    corecore