PaperPanorama
FAQ

Nuclear Theory·nucl-th

Wednesday·March 29, 2017

10 papers—6 primary·4 cross-listed

All10Primary6Cross-lists4
  1. 01

    [Submitted on 27 Mar 2017]

    EoS's of different phases of dense quark matter

    E. J. Ferrer🇺🇸

    Compact stars with significant high densities in their interiors can give rise to quark deconfined phases that can open a window for the study of strongly interacting dense nuclear matter. Recent observations on the mass of two pulsars, PSR J1614-2230 and PSR J0348+0432, have posed a great restriction on their composition, since their equations of state must be hard enough to support masses of about at least two solar masses. The onset of quarks tends to soften the equation of state, but due to their strong interactions, different phases can be realized with new parameters that affect the corresponding equations of state and ultimately the mass-radius relationships. In this paper I will review how the equation of state of dense quark matter is affected by the physical characteristics of the phases that can take place at different baryonic densities with and without the presence of a magnetic field, as well as their connection with the corresponding mass-radius relationship, which can be derived by using different models.

    Comments:
    11 pages, 7 figures, CSQCD-V Conference, L'Aquila, Italy, May 23-27, 2016
    Subjects:
    Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE); High Energy Physics — Phenomenology (hep-ph)
    arXiv:
    1703.09270 [pdf]
    2 citations
  2. 02

    [Submitted on 27 Mar 2017]

    Core-excitation effects in transfer reactions: Suppression or enhancement?

    A. Deltuva🇱🇹 · D. Jurčiukonis🇱🇹 · E. Norvaišas🇱🇹

    transfer reactions are described using momentum-space Faddeev-type equations for transition operators and including the vibrational excitation of the core. The available experimental cross section data at 10.5 MeV/nucleon beam energy for the ground state and excited state are quite well reproduced by our calculations including the core excitation. Its effect can be roughly simulated reducing the single-particle cross section by the corresponding spectroscopic factor. Consequently, the extraction of the spectroscopic factors taking the ratio of experimental data and single-particle cross section at this energy is a reasonable procedure. However, at higher energies core-excitation effects are much more complicated and have no simple relation to spectroscopic factors. We found that core-excitation effects are qualitatively very different for reactions with the orbital angular momentum transfer and , suppressing the cross sections for the former and enhancing for the latter, and changes the shape of the angular distribution in both cases. Furthermore, the core-excitation effect is a result of a complicated interplay between its contributions of the two- and three-body nature.

    Comments:
    6+ pages, 6 figures, submitted to Phys. Lett. B
    Subjects:
    Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
    arXiv:
    1703.09289 [pdf]
    PLB(2017)·11 citations
  3. 03

    [Submitted on 28 Mar 2017]

    Elliptic flows of light nuclei

    Xuejiao Yin🇨🇳 · Che Ming Ko🇺🇸 · Yifeng Sun🇺🇸 · Lilin Zhu🇨🇳

    Using the coalescence model based on nucleons from a blast-wave model with its parameters fitted to the measured proton transverse momentum spectrum and elliptic flow in heavy ion collisions at the Relativistic Heavy Ion Collider, we study the elliptic flows of light nuclei in these collisions. We find that to describe the measured elliptic flows of deuterons (anti-deuterons) and tritons (helium-3) requires that the emission source for nucleons of high transverse momentum is more elongated along the reaction plane than in the perpendicular direction. Our results thus suggest that the elliptic flows of light nuclei can be used to study the nucleon emission source in relativistic heavy ion collisions.

    Comments:
    7 pages, 5 figures
    Subjects:
    Nuclear Theory (nucl-th); Nuclear Experiment (nucl-ex)
    arXiv:
    1703.09383 [pdf]
    PRC(2017)·19 citations
  4. 04

    [Submitted on 28 Mar 2017]

    Luneburg-lens-like structural Pauli attractive core of nuclear force at short distances

    Shigeo Ohkubo🇯🇵

    The nuclear force has been understood to have a repulsive core at short distances, similar to a molecular force, since Jastrow proposed it in 1951. The existence of the repulsion was experimentally confirmed from the proton-proton scattering 1S_0 phase shift, which becomes negative beyond 230 MeV. This repulsion is essential for preventing the nucleon-nucleon system from collapsing by attraction. The origin of the repulsion has been considered to be due to the Pauli principle, similar to the repulsion originally revealed in alpha-alpha scattering, in many studies including recent lattice QCD calculations. On the other hand, very recently it was shown that an inter-nuclear potential including alpha-alpha interactions has a Luneburg-lens-like attraction at short distances rather than repulsion. We show that the nuclear force with an attractive potential at short distances that reproduces the experimental phase shifts well has a Luneburg-lens-like structural Pauli attractive core (SPAC) at short distances and acts as apparent repulsion. The apparent repulsion is caused by the deeply embedded unobservable Pauli forbidden state similar to nucleus-nucleus potentials.

    Comments:
    6 pages, 5 figures
    Subjects:
    Nuclear Theory (nucl-th); High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex)
    arXiv:
    1703.09396 [pdf]
    PRC(2017)·3 citations
  5. 05

    [Submitted on 28 Mar 2017]

    Resonance State Wave Functions of Be using Supersymmetric Quantum Mechanics

    S. K. Dutta · D. Gupta · Swapan K. Saha

    The theoretical procedure of supersymmetric quantum mechanics is adopted to generate the resonance state wave functions of the unbound nucleus Be. In this framework, we used a density dependent M3Y microscopic potential and arrived at the energy and width of the 1.8 MeV (5/2) resonance state. We did not find any other nearby resonances for Be. It becomes apparent that the present framework is a powerful tool to theoretically complement the increasingly important accelerator based experiments with unbound nuclei.

    Comments:
    5 pages, 4 figures, Phys. Lett. B (2017)
    Subjects:
    Nuclear Theory (nucl-th)
    arXiv:
    1703.09448 [pdf]
    PLB(2018)·7 citations
  6. 06

    [Submitted on 27 Mar 2017]

    Correlation femtoscopy study at NICA and STAR energies within a viscous hydrodynamic plus cascade model

    P. Batyuk🇷🇺 · Iu. Karpenko🇺🇦 · R.Lednicky🇷🇺 · L.Malinina🇷🇺 · K.Mikhaylov🇷🇺 · O. Rogachevsky🇷🇺 · D.Wielanek🇵🇱

    Correlation femtoscopy allows one to measure the space-time characteristics of particle production in relativistic heavy-ion collisions due to the effects of quantum statistics (QS) and final state interactions (FSI). The main features of the femtoscopy measurements at top RHIC and LHC energies are considered as a manifestation of strong collective flow and are well interpreted within hydrodynamic models employing equation of state (EoS) with a crossover type transition between Quark-Gluon Plasma (QGP) and hadron gas phases. The femtoscopy at lower energies was intensively studied at AGS and SPS accelerators and is being studied now in the Beam Energy Scan program (BES) at the BNL Relativistic Heavy Ion Collider in the context of exploration of the QCD phase diagram. In this article we present femtoscopic observables calculated for Au-Au collisions at GeV in a viscous hydro + cascade model vHLLE+UrQMD and their dependence on the EoS of thermalized matter.

    Comments:
    11 pages, 8 figures
    Subjects:
    Nuclear Theory (nucl-th); High Energy Physics — Experiment (hep-ex); High Energy Physics — Phenomenology (hep-ph)
    arXiv:
    1703.09628 [pdf]
    PRC(2017)·20 citations

Affiliations

first authorsco-authorsvia INSPIRE