scholarly journals Deconfined, massive quark phase at high density and compact stars: A holographic study

2020 ◽  
Vol 101 (12) ◽  
Author(s):  
Kazem Bitaghsir Fadafan ◽  
Jesús Cruz Rojas ◽  
Nick Evans
Keyword(s):  
High Density ◽  
Compact Stars ◽  
Massive Quark ◽  
Quark Phase ◽  
Holographic Study

scholarly journals The proton mass and scale-invariant hidden local symmetry for compressed baryonic matter

2017 ◽  
Vol 32 (35) ◽  
pp. 1747012 ◽  
Author(s):  
Mannque Rho
Keyword(s):  
Light Quark ◽  
Goldstone Boson ◽  
Local Symmetry ◽  
Heavy Ion ◽  
High Density ◽  
Compact Stars ◽  
Baryonic Matter ◽  
Solar Mass ◽  
Scale Invariant ◽  
Proton Mass

I discuss how to access dense baryonic matter of compact stars by combining hidden local symmetry (HLS) of light-quark vector mesons with spontaneously broken scale invariance of a (pseudo) Nambu–Goldstone boson, dilaton, in a description that parallels the approach to dilatonic Higgs. Some of the surprising observations are that the bulk of proton mass is not Nambu–Goldstonian, parity doubling emerges at high density and the EoS of baryonic matter can be soft enough for heavy-ion processes at low density and stiff enough at high density for [Formula: see text] solar mass neutron stars.

scholarly journals ENERGY RELEASE ASSOCIATED WITH QUARK PHASE TRANSITION IN NEUTRON STARS: COMPARATIVE ANALYSIS OF MAXWELL AND GLENDENNING SCENARIOS

2012 ◽  
Vol 18 ◽  
pp. 1-9
Author(s):  
ANI ALAVERDYAN ◽  
GRIGOR ALAVERDYAN ◽  
SHUSHAN MELIKYAN
Keyword(s):  
Phase Transition ◽  
Mean Field ◽  
Effective Field ◽  
Compact Stars ◽  
Relativistic Mean Field ◽  
Hadron Phase ◽  
First Order Phase Transition ◽  
Deconfinement Phase Transition ◽  
The One ◽  
Quark Phase

We study the compact stars internal structure and observable characteristics alterations due to the quark deconfinement phase transition. To proceed with, we investigate the properties of isospin- asymmetric nuclear matter in the improved relativistic mean-field (RMF) theory, including a scalar-isovector δ-meson effective field. In order to describe the quark phase, we use the improved version of the MIT bag model, in which the interactions between u, d and s quarks inside the bag are taken into account in the one-gluon exchange approximation. We compute the amount of energy released by the corequake for both cases of deconfinement phase transition scenarios, corresponding to the Maxwellian type ordinary first-order phase transition and the phase transition with formation of a mixed quark-hadron phase (Glendenning scenario).

Gamma-ray bursts generated from phase transition of neutron stars to quark stars

2017 ◽  
Vol 32 (04) ◽  
pp. 1750027 ◽  
Author(s):  
Xiao-Yu Shu ◽  
Yong-Feng Huang ◽  
Hong-Shi Zong
Keyword(s):  
Phase Transition ◽  
Neutron Stars ◽  
Gamma Ray ◽  
Mean Field ◽  
Gamma Ray Bursts ◽  
Compact Stars ◽  
Particle Model ◽  
Relativistic Mean Field ◽  
Quark Stars ◽  
Quark Phase

The evolution of compact stars is believed to be able to produce various violent phenomena in our universe. In this paper, we discuss the possibility that gamma-ray bursts (GRBs) might result from the phase transition of a neutron star to a quark star and calculate the energy released from the conversion. In our study, we utilize the relativistic mean field (RMF) theory to describe the hadronic phase of neutron stars, while an improved quasi-particle model is adopted to describe the quark phase of quark stars. With quark matter equation-of-state (EOS) more reliable than models used before, it is found that the energy released is of the order of 10[Formula: see text] erg, which confirms the validity of the phase transition model.

COMPACT STARS: A CORE-ENVELOPE MODEL

2002 ◽  
Vol 17 (38) ◽  
pp. 2535-2544 ◽  
Author(s):  
R. SHARMA ◽  
S. MUKHERJEE
Keyword(s):  
Inner Core ◽  
Compact Stars ◽  
Envelope Model ◽  
Quark Phase

Vaidya–Tikekar20 model has been generalised to describe cold compact stars having concentric layers of different phases. We illustrate the model by considering a star whose inner core has a deconfined quark phase, enveloped by less compact baryonic constituents.

scholarly journals Twin stars: probe of phase transition from hadronic to quark matter

2021 ◽  
Vol 252 ◽  
pp. 06001
Author(s):  
Themistoklis Deloudis ◽  
Polychronis Koliogiannis ◽  
Charalampos Moustakidis
Keyword(s):  
Phase Transition ◽  
Neutron Stars ◽  
Quark Matter ◽  
Compact Stars ◽  
Stable Configuration ◽  
First Order ◽  
Maxwell Construction ◽  
First Order Transition ◽  
Hybrid Stars ◽  
Quark Phase

In agreement with the gravitational-wave events which are constantly increasing, new aspects of the internal structure of compact stars have come to light. A scenario in which a first order transition takes place inside these stars is of particular interest as it can lead, under conditions, to a third gravitationally stable branch (besides white dwarfs and neutron stars). This is known as the twin star scenario. The new branch yields stars with the same mass as normal compact stars but quite different radii. In the current work, we focus on hybrid stars undergone a hadron to quark phase transition near their core and how this new stable configuration arises. Emphasis is to be given especially in the aspects of the phase transition and its parametrization in two different ways, namely with Maxwell construction and with Gibbs construction. Qualitative findings of mass-radius relations of these stars will also be presented.

scholarly journals INVESTIGATION OF THE EXISTENCE OF HYBRID STARS USING NAMBU–JONA–LASINIO MODELS

2010 ◽  
Vol 19 (08n10) ◽  
pp. 1521-1524 ◽  
Author(s):  
J. G. COELHO ◽  
C. H. LENZI ◽  
M. MALHEIRO ◽  
R. M. MARINHO ◽  
M. FIOLHAIS
Keyword(s):  
Phase Transition ◽  
Equation Of State ◽  
Neutron Stars ◽  
Quark Matter ◽  
Chemical Potential ◽  
Compact Stars ◽  
Vector Coupling ◽  
Njl Model ◽  
Hybrid Stars ◽  
Quark Phase

We investigate the hadron-quark phase transition inside neutron stars and obtain mass–radius relations for hybrid stars. The equation of state for the quark phase using the standard NJL model is too soft, leading to an unstable star and suggesting a modification of the NJL model by introducing a momentum cutoff dependent on the chemical potential. However, even in this approach, the instability remains. In order to remedy the instability we suggest the introduction of a vector coupling in the NJL model, which makes the EoS stiffer, reducing the instability. We conclude that the possible existence of quark matter inside the stars require high densities, leading to very compact stars.

Sign in / Sign up

Export Citation Format

Share Document