PaperPanorama

Nuclear Theory·nucl-th

Wednesday·September 14, 2022

8 papers5 primary·3 cross-listed

  1. 06

    Hadronization effects on transverse momentum dependent jet fragmentation function in small systems

    Xiang-Pan Duan🇨🇳 · Wenbin Zhao🇺🇸 · Guo-Liang Ma🇨🇳

    The transverse momentum -dependent jet fragmentation functions have been investigated in proton+proton (p p) and proton+lead (p Pb) collisions at with a multiphase transport model containing both a simple quark coalescence mechanism and a new hybrid hadronization mechanism with coalescence and fragmentation processes. Hadronized by the new hadronization mechanism, the AMPT model achieves a quantitative description of the -dependent jet fragmentation functions measured by ALICE. Besides, no obvious jet-medium interaction and cold nuclear matter effects on the -dependent jet fragmentation functions in p Pb collisions were observed. We found the -dependent jet fragmentation functions are dominated by the quark coalescence contribution for the new hadronization mechanism, which can be decomposed into narrow and wide parts. The root mean square value of the wide part depends on the jet radius and jet transverse momentum , which is sensitive to different hadronization mechanisms and their components. Therefore, the -dependent jet fragmentation functions are proposed as a sensitive probe to study the non-perturbative hadronization effect of jets in small colliding systems.

    hep-phnucl-exnucl-thEur.Phys.J.Plus(2023)·4 citations
  2. 07

    Neutron star inner crust: reduction of shear modulus by nuclei finite size effect

    Nikita A. Zemlyakov · Andrey I. Chugunov

    The elasticity of neutron star crust is important for adequate interpretation of observations. To describe elastic properties one should rely on theoretical models. The most widely used is Coulomb crystal model (system of point-like charges on neutralizing uniform background), in some works it is corrected for electron screening. These models neglect finite size of nuclei. This approximation is well justified except for the innermost crustal layers, where nuclei size becomes comparable with the inter-nuclear spacing. Still, even in those dense layers it seems reasonable to apply the Coulomb crystal result, if one assumes that nuclei are spherically symmetric: Coulomb interaction between them should be the same as interaction between point-like charges. This argument is indeed correct, however, as we point here, shear of crustal lattice generates (microscopic) quadrupole electrostatic potential in a vicinity of lattice cites, which induces deformation on the nuclei. We analyze this problem analytically within compressible liquid drop model, using ionic spheroid model (which is generalization of well known ion sphere model). In particular, for ground state crust composition the effective shear modulus is reduced for a factor of , where u is the filling factor (ratio of the nuclei volume to the volume of the cell). This result is universal and does not depend on the applied nucleon interaction model. For the innermost layers of inner crust u~0.2 leading to reduction of the shear modulus by ~25%, which can be important for correct interpretation of quasi-periodic oscillations in the tails of magnetar flares.

    astro-ph.HEnucl-thMNRAS(2022)·10 citations
  3. 08

    Investigating the role of partonic and hadronic dynamics in mass splitting of elliptic anisotropy in p-Pb collisions at = 5.02 TeV

    Debojit Sarkar🇮🇳 · Subikash Choudhury🇮🇳 · Subhasis Chattopadhyay🇮🇳

    The mass ordering of is regarded as one of the key signatures of collective behaviour in ultra relativistic heavy ion collisions. This observation has been found to be in compliance with the hydrodynamical response of a strongly interacting system to the initial spatial anisotropy. Flow co-efficients measured with identified particles in p-Pb/d-Au collisions have shown similar mass-splitting of indicating towards the presence of collective dynamics in small collision systems. Arguably, small size in the overlap geometry of such colliding systems may not be suitable for hydrodynamical treatment that demands an early thermalization. Studies based on a multi phase transport model suggests that elliptic or triangular anisotropy is primarily due to escape mechanism of partons rather than hydro like collectivity and mass ordering of can be generated from coalescence dynamics as implemented in string melting version of AMPT even when parton azimuthal directions are randomized. In this work, studies have been performed on p-Pb collisions at = 5.02 TeV using AMPT model which has been found to explain the elliptic and traingular flow in such a system where escape mechanism is the dominant source of flow generation. We report that the mass splitting of can originate independently both at the partonic and hadronic level in the string melting version of the AMPT model.

    hep-phhep-exnucl-thPRC(2016)·7 citations

Affiliations

first authorsco-authorsvia INSPIRE