PaperPanorama
FAQ

Nuclear Theory·nucl-th

Friday·October 7, 2016

6 papers—3 primary·3 cross-listed

All6Primary3Cross-lists3
  1. 04

    [Submitted on 5 Oct 2016] (cross-list from cond-mat.quant-gas)

    Higher-Harmonic Collective Modes in a Trapped Gas from Second-Order Hydrodynamics

    William E. Lewis · Paul Romatschke

    Utilizing a second-order hydrodynamics formalism, the dispersion relations for the frequencies and damping rates of collective oscillations as well as spatial structure of these modes up to the decapole oscillation in both two- and three- dimensional gas geometries are calculated. In addition to higher-order modes, the formalism also gives rise to purely damped "non-hydrodynamic" modes. We calculate the amplitude of the various modes for both symmetric and asymmetric trap quenches, finding excellent agreement with an exact quantum mechanical calculation. We find that higher-order hydrodynamic modes are more sensitive to the value of shear viscosity, which may be of interest for the precision extraction of transport coefficients in Fermi gas systems.

    Comments:
    16 pages, 10 figures
    Subjects:
    Quantum Gases (cond-mat.quant-gas); Nuclear Theory (nucl-th)
    arXiv:
    1610.01611 [pdf]
    New J.Phys.(2017)·3 citations
  2. 05

    [Submitted on 6 Oct 2016] (cross-list from hep-ph)

    Oscillations in counting statistics

    Grzegorz Wilk🇵🇱 · Zbigniew Wlodarczyk🇵🇱

    The very large transverse momenta and large multiplicities available in present LHC experiments on pp collisions allow a much closer look at the corresponding distributions. Some time ago we discussed a possible physical meaning of apparent log-periodic oscillations showing up in p_T distributions (suggesting that the exponent of the observed power-like behavior is complex). In this talk we concentrate on another example of oscillations, this time connected with multiplicity distributions P(N). We argue that some combinations of the experimentally measured values of P(N) (satisfying the recurrence relations used in the description of cascade-stochastic processes in quantum optics) exhibit distinct oscillatory behavior, not observed in the usual Negative Binomial Distributions used to fit data. These oscillations provide yet another example of oscillations seen in counting statistics in many different, apparently very disparate branches of physics further demonstrating the universality of this phenomenon.

    Comments:
    Invited talk at ISMD2016, Seogwipo, Jeju Island, South Korea, 29.08-02.09.2016, to be published in EPJ Web of Conferences
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    1610.01890 [pdf]
    EPJ Web Conf.(2017)·3 citations
  3. 06

    [Submitted on 6 Oct 2016] (cross-list from hep-th)

    Holography, Hydrodynamization and Heavy-Ion Collisions

    Michal P. Heller🇨🇦

    In the course of the past several years holography has emerged as an ab initio tool in exploring strongly-time-dependent phenomena in gauge theories. These lecture notes overview recent developments in this area driven by phenomenological questions concerning applicability of hydrodynamics (hydrodynamization) under extreme conditions occurring in ultrarelativistic heavy-ion collisions at RHIC and LHC. The topics include hydrodynamization time scale, holographic collisions, as well as hydrodynamization from the point of view of the asymptotic character of the hydrodynamic gradient expansion. The emphasis is put on concepts rather than calculational techniques and a particular attention is devoted to present these developments in the context of the most recent advances and some of the open problems.

    Comments:
    32 pages, 7 figures, lecture notes from the 56th Cracow School of Theoretical Physics "A Panorama of Holography"; v2: typos fixed, added references; v3: further typos fixed and references added, matches the published version
    Subjects:
    High Energy Physics — Theory (hep-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
    arXiv:
    1610.02023 [pdf]
    Acta Phys.Polon.B(2016)·49 citations

Affiliations

first authorsco-authorsvia INSPIRE