PaperPanorama

Nuclear Theory·nucl-th

Wednesday·May 4, 2016

9 papers6 primary·3 cross-listed

  1. 07

    [Submitted on 2 May 2016] (cross-list from nucl-ex)

    Aspects of the momentum dependence of the equation of state and of the residual cross section, and their effects on nuclear stopping

    Z. Basrak🇭🇷 · P. Eudes🇫🇷 · V. de la Mota🇫🇷

    With the semiclassical Landau-Vlasov transport model we studied the stopping observable , the energy-based isotropy ratio, for the Xe\,+\,Sn reaction at beam energies spanning 12 to 100 MeV. We investigated the impacts of the nonlocality of the nuclear mean field, of the in-medium modified nucleon-nucleon () cross section and of the reaction centrality. A fixed set of model parameters yields values that favorably compare with the experimental ones, but only for energies below the Fermi energy . Above agreement is readily possible, but by a smooth evolution with energy of the parameter that controls the in-medium modification of cross section. By comparing the simulation correction factor applied to the free cross section with the one deduced from experimental data [Phys.\ Rev.\ C\,{\bf 90}, 064602 (2014)], we infer that the zero-range mean field almost entirely reproduces it. Also, in accordance with what has been deduced from experimental data, around a strong reduction of the free cross section is found. In order to test the impact of sampling central collisions by multiplicity an event generator (HIPSE) was used. We obtain that high multiplicity events are spread over a broad impact parameter range, but it turns out that this has a small effect on the observable and, thus, on as well.

    Comments:
    10 pages, 5 figures, 1 appendix
    Subjects:
    Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    1605.00679 [pdf]
    PRC(2016)·23 citations
  2. 08

    [Submitted on 3 May 2016] (cross-list from hep-ph)

    Spectral functions and in-medium properties of hadrons

    Ralf-Arno Tripolt🇮🇹 · Lorenz von Smekal🇩🇪 · Jochen Wambach🇮🇹

    The in-medium modifications of hadron properties such as masses and decay widths have been a major focus of the scientific work of Gerry Brown and the insights gained by him and his collaborators made them major drivers of this field for several decades. Their prediction of experimental signals in di-lepton pair production in relativistic heavy-ion collisions were instrumental in initiating large experimental campaigns which continue until today. In this chapter we review recent results which elucidate the relation of hadronic spectral properties at finite temperature and density to the restoration of spontaneously broken chiral symmetry.

    Comments:
    Contribution to the Gerry Brown memorial book published by World Scientific
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Theory (hep-th); Nuclear Theory (nucl-th)
    arXiv:
    1605.00771 [pdf]
    IJMPE(2017)·22 citations
  3. 09

    [Submitted on 3 May 2016] (cross-list from hep-ph)

    Transverse pion structure beyond leading twist in constituent models

    C. Lorcé (Ecole Polytechnique, CPHT)🇫🇷 · B. Pasquini (Pavia U. & INFN, Pavia)🇮🇹 · P. Schweitzer (Connecticut U. and Tubingen U.)🇩🇪

    The understanding of the pion structure as described in terms of transverse-momentum dependent parton distribution functions (TMDs) is of importance for the interpretation of currently ongoing Drell-Yan experiments with pion beams. In this work we discuss the description of pion TMDs beyond leading twist in a pion model formulated in the light-front constituent framework. For comparison, we also review and derive new results for pion TMDs in the bag and spectator models.

    Comments:
    17 pages, 7 figures; v2: modified presentation, updated references; matches the journal version
    Subjects:
    High Energy Physics — Phenomenology (hep-ph); High Energy Physics — Experiment (hep-ex); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    1605.00815 [pdf]
    EPJC(2016)·48 citations

Affiliations

first authorsco-authorsvia INSPIRE