PaperPanorama

Nuclear Theory·nucl-th

Thursday·September 22, 2016

7 papers4 primary·3 cross-listed

  1. 01

    [Submitted on 21 Sept 2016]

    Coupled-channels description of the 40Ca+58,64Ni transfer and fusion reactions

    G. Scamps🇯🇵 · D. Bourgin🇫🇷 · K. Hagino🇯🇵 · F. Haas🇫🇷 · S. Courtin🇫🇷

    Preliminary experimental data for nucleon transfer reactions of the 40Ca+58Ni and 40Ca+64Ni systems are analyzed with the coupled- channels approach. It is shown that a simple treatment for the transfer in the coupled-channels method cannot reproduce simultaneously the transfer probabilities and the sub-barrier enhancement of fusion cross sections.

    Comments:
    5 pages, 2 figures, Proceeding of the "International Workshop on Multi facets of EOS and Clustering"
    Subjects:
    Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
    arXiv:
    1609.06428 [pdf]
    Nuovo Cim.C(2017)·1 citation
  2. 02

    [Submitted on 21 Sept 2016]

    Medium effects on heavy-flavour observables in high-energy nuclear collisions

    Andrea Beraudo🇮🇹

    The peculiar role of heavy-flavour observables in relativistic heavy-ion collisions is discussed. Produced in the early stage, and quarks cross the hot medium arising from the collision, interacting strongly with the latter, until they hadronize. Depending on the strength of the interaction heavy quarks may or not approach kinetic equilibrium with the plasma, tending in the first case to follow the collective flow of the expanding fireball. The presence of a hot deconfined medium may also affect heavy-quark hadronization, being possible for them to recombine with the surrounding light thermal partons, so that the final heavy-flavour hadrons inherit part of the flow of the medium. Here we show how it is possible to develop a complete transport setup allowing one to describe heavy-flavour production in high-energy nuclear collisions, displaying some major results one can obtain. Finally, the possibility that the formation of a hot deconfined medium even in small systems (high-multiplicity p-Au and d-Au collisions, so far) may affect also heavy-flavour observables is investigated.

    Comments:
    Invited talk at the conference QCD@Work 2016 - Martina Franca (Italy)
    Subjects:
    Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
    arXiv:
    1609.06449 [pdf]
    EPJ Web Conf.(2016)·1 citation
  3. 03

    [Submitted on 21 Sept 2016]

    Systematic study on probable projectile-target combinations for the synthesis of the 120 superheavy nucleus

    K. P. Santhosh · V. Safoora

    Probable projectile-target combinations for the synthesis of superheavy element 120 have been studied taking Coulomb and proximity potential as the interaction barrier. The probabilities of compound nucleus formation, PCN for the projectile-target combinations found in the cold reaction valley of 120 are estimated. At energies near and above the Coulomb barrier, we have calculated the capture, fusion and evaporation residue cross sections for the reactions of all the probable projectile-target combinations so as to predict the most promising projectile-target combinations for the synthesis of SHE 120 in heavy ion fusion reactions. The calculated fusion and evaporation cross section for the more asymmetric (hotter) projectile-target combination is found to be higher than the less asymmetric (colder) combination. It can be seen from the nature of quasi-fission barrier height, mass asymmetry, probability of compound nucleus formation, survival probability and excitation energy, the systems Ar + No, Ar + No, Ca + Fm, Ca + Fm, Ti + Cf, Cr + Cm in the deep region I of cold reaction valley, and the systems Fe + Pu, Fe + Pu, Ni + U, Ni + U, Ni + U, Zn + Th in the other cold valleys are identified as the better projectile-target combinations for the synthesis of 120. Our prediction on the synthesis of 120 superheavy nuclei using the combinations Cr+Cm, Fe+Pu, Ni+U and Ti+Cf are compared with available experimental data and other theoretical predictions.

    Comments:
    46 pages, 27 figures
    Subjects:
    Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
    arXiv:
    1609.06467 [pdf]
    PRC(2016)·21 citations
  4. 04

    [Submitted on 21 Sept 2016]

    Initial Temperature and Extent of Chemical Equilibration of Partons in Relativistic Collision of Heavy Nuclei

    Dinesh K. Srivastava🇮🇳 · Rupa Chatterjee🇮🇳 · Munshi G. Mustafa🇮🇳

    We emphasize that a knowledge of energy and entropy densities of quark gluon plasma - a thermalized de-confined matter, formed in relativistic heavy ion collisions fixes the formation temperature and the product of gluon fugacity and formation time uniquely, {\em provided} we know the relative fugacities of quarks and gluons. This also provides that a smaller formation time would imply larger fugacities for partons. Next we explore the limits of chemical equilibration of partons during the initial stages in relativistic collision of heavy nuclei. The experimentally measured rapidity densities of transverse energy and charged particle multiplicity at RHIC and LHC energies are used to estimate the energy and number densities with the assumption of formation of a thermally equilibrated quark gluon plasma which may be chemically equilibrated to the same or differing extents for quarks and gluons. The estimates are found to be very sensitive to the correction factor used for the Björken energy density for identifying it with the initial energy density. The extent of chemical equilibration near the end of the QGP phase is inferred by solving master equations by including the processes and along with expansion and cooling of the plasma. The possible consequences for invariant mass distribution of intermediate mass dileptons radiated from the plasma are discussed which could distinguish between different scenarios.

    Comments:
    13 page, 13 figures, 2 tables
    Subjects:
    Nuclear Theory (nucl-th)
    arXiv:
    1609.06496 [pdf]
    J.Phys.G(2018)·8 citations

Affiliations

first authorsco-authorsvia INSPIRE