Nuclear Theory·nucl-th

Thursday·June 29, 2017

8 papers—2 primary·6 cross-listed

01
[Submitted on 28 Jun 2017]
The application of the Quark-Hadron Chiral Parity-Doublet Model to neutron star matter
A. Mukherjee🇩🇪 · S. Schramm🇩🇪 · J. Steinheimer🇩🇪 · V. Dexheimer🇺🇸
The Quark-Hadron Chiral Parity-Doublet model (Q $χ$ P) is applied to calculate compact star properties in the presence of a deconfinement phase transition. Within this model, a consistent description of nuclear matter properties, chiral symmetry restoration, and a transition from hadronic to quark and gluonic degrees of freedom is possible within one unified approach. We find that the equation of state obtained is consistent with recent perturbative quantum chromodynamics (QCD) results and is able to accommodate observational constraints of massive and small neutron stars. Furthermore, we show that important features of the equation of state, such as the symmetry energy and its slope, are well within their observational constraints.
Comments:
8 pages, 9 figures and 1 table
Subjects:
Nuclear Theory (nucl-th); High Energy Astrophysical Phenomena (astro-ph.HE)
arXiv:
1706.09191 [pdf]
Astron.Astrophys.(2017)·48 citations
02
[Submitted on 28 Jun 2017]
Projection after variation in the finite-temperature Hartree-Fock-Bogoliubov approximation
P. Fanto
The finite-temperature Hartree-Fock-Bogoliubov (HFB) approximation often breaks symmetries of the underlying many-body Hamiltonian. Restricting the calculation of the HFB partition function to a subspace with good quantum numbers through projection after variation restores some of the correlations lost in breaking these symmetries, although effects of the broken symmetries such as sharp kinks at phase transitions remain. However, the most general projection after variation formula in the finite-temperature HFB approximation is limited by a sign ambiguity. Here, we extend the Pfaffian formula for the many-body traces of HFB density operators introduced by L. M. Robledo in Ref. [1] to eliminate this sign ambiguity and evaluate the more complicated many-body traces required in projection after variation in the most general HFB case. We validate our method through a proof-of-principle calculation of the particle-number-projected HFB thermal energy in a simple model.
Comments:
6 pages, 1 figure
Subjects:
Nuclear Theory (nucl-th); Mesoscale and Nanoscale Physics (cond-mat.mes-hall); Superconductivity (cond-mat.supr-con)
arXiv:
1706.09373 [pdf]
PRC(2017)·4 citations
03
[Submitted on 27 Jun 2017] (cross-list from hep-ph)
Color Screening and Regeneration of Bottomonia in High-Energy Heavy-Ion Collisions
Xiaojian Du🇺🇸 · Min He🇨🇳 · Ralf Rapp🇺🇸
The production of ground-state and excited bottomonia in ultrarelativistic heavy-ion collisions is investigated within a kinetic-rate equation approach including regeneration. We augment our previous calculations by an improved treatment of medium effects, with temperature-dependent binding energies and pertinent reaction rates, $B$ -meson resonance states in the equilibrium limit near the hadronization temperature, and a lattice-QCD based equation of state for the bulk medium. In addition to the centrality dependence of the bottomonium yields we compute their transverse-momentum ( $p_{T}$ ) spectra and elliptic flow with momentum-dependent reaction rates and a regeneration component based on $b$ -quark spectra from a nonperturbative transport model of heavy-quark diffusion. The latter has noticeable consequences for the shape of the bottomonium $p_{T}$ spectra. We quantify how uncertainties in the various modeling components affect the predictions for observables. Based on this we argue that the $Υ (1 S)$ suppression is a promising observable for mapping out the in-medium properties of the QCD force, while $Υ (2 S)$ production can help to quantify the role of regeneration from partially thermalized $b$ quarks.
Comments:
26 pages, 52 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1706.08670 [pdf]
PRC(2017)·198 citations
04
[Submitted on 27 Jun 2017] (cross-list from cond-mat.quant-gas)
Trial wave functions for ring-trapped ions and neutral atoms: Microscopic description of the quantum space-time crystal
Constantine Yannouleas · Uzi Landman
A constructive theoretical platform for the description of quantum space-time crystals uncovers for $N$ interacting and ring-confined rotating particles the existence of low-lying states with proper space-time crystal behavior. The construction of the corresponding many-body trial wave functions proceeds first via symmetry breaking at the mean-field level followed by symmetry restoration using projection techniques. The ensuing correlated many-body wave functions are stationary states and preserve the rotational symmetries, and at the same time they reflect the point-group symmetries of the mean-field crystals. This behavior results in the emergence of sequences of select magic angular momenta $L_{m}$ . For angular-momenta away from the magic values, the trial functions vanish. Symmetry breaking beyond mean field can be induced by superpositions of such good- $L_{m}$ many-body stationary states. We show that superposing a pair of adjacent magic angular momenta states leads to formation of special broken-symmetry states exhibiting quantum space-time-crystal behavior. In particular, the corresponding particle densities rotate around the ring, showing undamped and nondispersed periodic crystalline evolution in both space and time. The experimental synthesis of such quantum space-time-crystal wave packets is predicted to be favored in the vicinity of ground-state energy crossings of the Aharonov-Bohm-type spectra accessed via an externally applied magnetic field. These results are illustrated here for Coulomb-repelling fermionic ions and for a lump of contact-interaction attracting bosons.
Comments:
14 pages, 3 color figures. Accepted for publication in Phys. Rev. A. This version incorporates extensive explanations, clarifications, and commentary concerning the connection of the present manuscript to previous literature. For related publications, see http://www.prism.gatech.edu/~ph274cy/
Subjects:
Quantum Gases (cond-mat.quant-gas); Nuclear Theory (nucl-th); Quantum Physics (quant-ph)
arXiv:
1706.09006 [pdf]
PRA(2017)·1 citation
05
[Submitted on 27 Jun 2017] (cross-list from hep-lat)
Feynman-Hellmann theorem for resonances and the quest for QCD exotica
J. Ruiz de Elvira🇨🇭 · U.-G. Meißner🇩🇪 · A. Rusetsky🇩🇪 · G. Schierholz🇩🇪
The generalization of the Feynman-Hellmann theorem for resonance states in quantum field theory is derived. On the basis of this theorem, a criterion is proposed to study the possible exotic nature of certain hadronic states emerging in QCD. It is shown that this proposal is supported by explicit calculations in Chiral Perturbation Theory and by large- $N_{c}$ arguments. Analyzing recent lattice data on the quark mass dependence in the pseudoscalar, vector meson, baryon octet and baryon decuplet sectors, we conclude that, as expected, these are predominately quark-model states, albeit the corrections are non-negligible.
Comments:
26 pages, 2 figures
Subjects:
High Energy Physics — Lattice (hep-lat); High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1706.09015 [pdf]
EPJC(2017)·25 citations
06
[Submitted on 28 Jun 2017] (cross-list from physics.atom-ph)
Theoretical study on the hyperfine interaction constants and the isotope shift factors for the $3 s^{2}^{1} S_{0} - 3 s 3 p^{3, 1} P_{1}^{o}$ transitions in Al $^{+}$
Tingxian Zhang · Luyou Xie · Jiguang Li · Zehuang Lu
We calculated the magnetic dipole and the electric quadrupole hyperfine interaction constants of 3s3p $^{3, 1} P_{1}^{o}$ states and the isotope shift, including mass and field shift, factors for transitions from these two states to the ground state 3s $^{2}^{1} S_{0}$ in Al $^{+}$ ions using the multiconfiguration Dirac-Hartree-Fock method. The effects of the electron correlations and the Breit interaction on these physical quantities were investigated in detail based on the active space approach. It is found that the CC and the higher-order correlations are considerable for evaluating the uncertainties of the atomic parameters concerned. The uncertainties of the hyperfine interaction constants in this work are less than 1.5\%. Although the isotope shift factors are highly sensitive to the electron correlations, reasonable uncertainties were obtained by exploring the effects of the electron correlations. Moreover, we found that the relativistic nuclear recoil corrections to the mass shift factors are very small and insensitive to the electron correlations for Al $^{+}$ . These atomic parameters present in this work are valuable for extracting the nuclear electric quadrupole moments and the mean-square charge radii of Al isotopes.
Comments:
accepted by Phys. Rev. A
Subjects:
Atomic Physics (physics.atom-ph); Nuclear Theory (nucl-th)
arXiv:
1706.09104 [pdf]
PRA(2017)·4 citations
07
[Submitted on 28 Jun 2017] (cross-list from hep-ph)
Bottomonia Suppression in Heavy Ion Collisions from AdS/CFT
N. N. Barnard🇿🇦 · W. A. Horowitz🇿🇦
We compute for the first time the suppression of bottomonia in a strongly coupled QGP and compare the results to those from a weakly coupled QGP. Using imaginary time techniques we numerically determine the real and imaginary parts of the ground state binding energy of the bottomonia in one potential computed from AdS/CFT and another computed from pQCD. We then use these binding energies in a suppression model to determine the $Υ$ (1S) nuclear modification factor in $s_{N N} = 2.76$ TeV Pb+Pb collisions. AdS/CFT significantly overpredicts the suppression compared to data, although the predictive power of our calculation is limited by its significant sensitivity to the exact details of the suppression model.
Comments:
12 pages, 5 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1706.09217 [pdf]
PRC(2020)·5 citations
08
[Submitted on 28 Jun 2017] (cross-list from hep-ph)
Interaction and Identification of the Doubly Heavy Di-Hadronic Molecules
D. P. Rathaud🇮🇳 · Ajay Kumar Rai🇮🇳
We study the interesting problem of interaction and identification of the hadronic molecules which seem to be deuteron-like structure. In particular, we propose a binding mechanism in which One Boson Exchange Potential plus Yukawa screen-like potential is applied in their relative s-wave state. We propose the dipole-like interaction between two color neutral states to form a hadronic molecule. For the identification of the hadronic molecules, the Weinberg's compositeness theorem is used to distinguish the molecule from confined (elementary) state. The present formalism predict some di-hadronic molecular states, involving quarks (s, c, b or $s$ , $c$ , $b$ ) as a constituents, namely, $p n$ , $K K$ , $ρ ρ$ , $K^{*} K^{*}$ , $D D^{*}$ ( $D D^{*}$ ), $D^{*} D^{*}$ , $B B^{*}$ , $B^{*} B^{*}$ , $D^{*\pm} D_{1}^{0}$ , $D^{0} K^{\pm}$ , $D^{* 0} K^{\pm}$ , with their possible quantum numbers.
Comments:
10 pages
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1706.09323 [pdf]
5 citations

Affiliations

first authorsco-authorsvia INSPIRE