HEAVY-ION AND ASTROPHYSICS CONSTRAINTS IN THE PARAMETRIC COUPLING MODEL

2010 ◽  
Vol 19 (08n10) ◽  
pp. 1667-1672
Author(s):  
M. GROHMANN ◽  
C. A. Z. VASCONCELLOS ◽  
G. F. MARRANGHELLO ◽  
F. FERNÁNDEZ
Keyword(s):  
Neutron Star ◽  
Neutron Stars ◽  
Nuclear Matter ◽  
Observational Data ◽  
Compression Modulus ◽  
Coupling Model ◽  
Heavy Ion ◽  
Coupling Constants ◽  
Wide Range ◽  
Parametric Coupling

The relativistic parametric coupling model is used here to describe global static properties of nuclear matter and neutron stars. Using recent observational data related to neutron star properties and experimental results of heavy-ion collisions, we review some properties of the effective model and we impose this way new constraints on its coupling constants. Then we analyze the consequences on already known parameters of nuclear matter, i.e., the compression modulus, the effective nucleon mass and the maximum neutron star mass predicted by integrating the Tolman–Oppenheimer–Volkoff equations. We make use of recent data on flow analysis to constrain the parameters of the theory and to achieve this goal, and have explored the parametric coupling model in a wide range of parameters. Our predictions for the compression modulus of nuclear matter and for the maximum mass of neutron stars are in good agreement with the observational data.

HEAVY ION CONSTRAINTS IN THE PARAMETRIC COUPLING MODEL

2010 ◽  
Vol 19 (10) ◽  
pp. 1935-1946
Author(s):  
GUILHERME F. MARRANGHELLO ◽  
CESAR A. Z. VASCONCELLOS
Keyword(s):  
Neutron Star ◽  
Neutron Stars ◽  
Nuclear Matter ◽  
Observational Data ◽  
Compression Modulus ◽  
Coupling Model ◽  
Heavy Ion ◽  
Coupling Constants ◽  
Wide Range ◽  
Parametric Coupling

The relativistic parametric coupling model is used here to describe global static properties of nuclear matter and neutron stars. Using recent observational data related to neutron star properties and experimental results of heavy-ion collisions, we review some properties of the effective model and we impose this way new constraints on its coupling constants. Then we analyze the consequences on already known parameters of nuclear matter, i.e., the compression modulus, the effective nucleon mass, and the maximum neutron star mass predicted by integrating the Tolman–Oppenheimer–Volkoff equations. To achieve this goal, we have explored the parametric coupling model in a wide range of parameters. We made use of recent data on flow analysis to constraint this parameter. Our results indicate values for the compression modulus of nuclear matter and for the maximum mass of neutron stars which are in good agreement with the observational data.

PARAMETRIC COUPLING MODEL: RECENT ADVANCES

2010 ◽  
Vol 19 (08n10) ◽  
pp. 1463-1468
Author(s):  
G. F. MARRANGHELLO ◽  
C. PROVIDÊNCIA ◽  
A. M. S. DOS SANTOS
Keyword(s):  
Neutron Star ◽  
Nuclear Matter ◽  
Coupling Model ◽  
Heavy Ion ◽  
Small Range ◽  
Heavy Ion Collision ◽  
Asymmetric Nuclear Matter ◽  
Parametric Coupling ◽  
Free Parameters ◽  
Ion Collision

We review the properties of the parametric coupling model and analyze its results when considering neutron star observations and heavy-ion collision experiments, specially those concerning the isospin characteristics of symmetric and asymmetric nuclear matter. By the end of the analysis, we are able to constrain the free parameters to a very small range of acceptable values.

EFFECTS OF IN-MEDIUM MODIFICATION OF WEAKLY INTERACTING LIGHT BOSON MASS IN NEUTRON STARS

2011 ◽  
Vol 26 (05) ◽  
pp. 367-375 ◽  
Author(s):  
A. SULAKSONO ◽  
MARLIANA ◽  
KASMUDIN
Keyword(s):  
Neutron Star ◽  
Binding Energy ◽  
Neutron Stars ◽  
Nuclear Matter ◽  
Observational Data ◽  
Boson Mass ◽  
Characteristic Scale ◽  
Neutron Star Matter ◽  
Weakly Interacting ◽  
Medium Modification

The effects of the presence of weakly interacting light boson (WILB) in neutron star matter have been revisited. Direct checking based on the experimental range of symmetric nuclear matter binding energy1 and the fact that the presence of this boson should give no observed effect on the crust properties of neutron star matter, shows that the characteristic scale of WILB [Formula: see text] should be ≤2 GeV-2. The recent observational data with significant low neutron stars radii2 and the recent largest pulsar which has been precisely measured, i.e. J1903+0327 (Ref. 3) indicate that in-medium modification of WILB mass in neutron stars cannot be neglected.

scholarly journals Probing Dense Nuclear Matter in the Laboratory: Experiments at FAIR and NICA

Universe ◽  
2021 ◽  
Vol 7 (6) ◽  
pp. 171
Author(s):  
Peter Senger
Keyword(s):  
Phase Transition ◽  
Neutron Star ◽  
Neutron Stars ◽  
Nuclear Matter ◽  
Quark Matter ◽  
Heavy Ion Collisions ◽  
Laboratory Experiments ◽  
Heavy Ion ◽  
High Density ◽  
Ion Collisions

The poorly known properties of high-density strongly-interacting matter govern the structure of neutron stars and the dynamics of neutron star mergers. New insight has been and will be gained by astronomical observations, such as the measurement of mass and radius of neutron stars, and the detection of gravitational waves emitted from neutron star mergers. Alternatively, information on the Nuclear Matter Equation-of-State (EOS) and on a possible phase transition from hadronic to quark matter at high baryon densities can be obtained from laboratory experiments investigating heavy-ion collisions. Detector systems dedicated to such experiments are under construction at the “Facility for Antiproton and Ion Research” (FAIR) in Darmstadt, Germany, and at the “Nuclotron-based Ion Collider fAcility” (NICA) in Dubna, Russia. In heavy-ion collisions at these accelerator centers, one expects the creation of baryon densities of up to 10 times saturation density, where quark degrees-of-freedom should emerge. This article reviews the most promising observables in heavy-ion collisions, which are used to probe the high-density EOS and possible phase transition from hadronic to quark matter. Finally, the facilities and the experimental setups will be briefly described.

scholarly journals Nuclear equation of state and neutron star cooling

2017 ◽  
Vol 26 (04) ◽  
pp. 1750015 ◽  
Author(s):  
Yeunhwan Lim ◽  
Chang Ho Hyun ◽  
Chang-Hwan Lee
Keyword(s):  
Neutron Star ◽  
Equation Of State ◽  
Neutron Stars ◽  
Nuclear Matter ◽  
Thermal Evolution ◽  
Observation Data ◽  
Nuclear Equation Of State ◽  
The Core ◽  
Dense Nuclear Matter ◽  
Nuclear Models

In this paper, we investigate the cooling of neutron stars with relativistic and nonrelativistic models of dense nuclear matter. We focus on the effects of uncertainties originated from the nuclear models, the composition of elements in the envelope region, and the formation of superfluidity in the core and the crust of neutron stars. Discovery of [Formula: see text] neutron stars PSR J1614−2230 and PSR J0343[Formula: see text]0432 has triggered the revival of stiff nuclear equation of state at high densities. In the meantime, observation of a neutron star in Cassiopeia A for more than 10 years has provided us with very accurate data for the thermal evolution of neutron stars. Both mass and temperature of neutron stars depend critically on the equation of state of nuclear matter, so we first search for nuclear models that satisfy the constraints from mass and temperature simultaneously within a reasonable range. With selected models, we explore the effects of element composition in the envelope region, and the existence of superfluidity in the core and the crust of neutron stars. Due to uncertainty in the composition of particles in the envelope region, we obtain a range of cooling curves that can cover substantial region of observation data.

scholarly journals Neutron star masses

2012 ◽  
Vol 8 (S291) ◽  
pp. 146-146
Author(s):  
David Nice
Keyword(s):  
Neutron Star ◽  
Equation Of State ◽  
Nuclear Matter ◽  
Observational Data ◽  
Mass Distribution ◽  
Binary Star ◽  
Star Mass ◽  
Star Evolution ◽  
Neutron Star Mass ◽  
Present Understanding

AbstractNeutron star masses can be inferred from observations of binary pulsar systems, particularly by the measurement of relativistic phenomena within these orbits. The observed distribution of masses can be used to infer or constrain the equation of state for nuclear matter and to study astrophysical processes such as supernovae and binary star evolution. In this talk, I will review our present understanding of the neutron star mass distribution with an emphasis on the observational data.

THE ROLE OF THE NUCLEAR MATTER COMPRESSION MODULUS IN NEUTRON STARS

2004 ◽  
Vol 13 (07) ◽  
pp. 1519-1524 ◽  
Author(s):  
VERÔNICA A. DEXHEIMER ◽  
CÉSAR A. Z. VASCONCELLOS ◽  
MOISÉS RAZEIRA ◽  
MANFRED DILLIG
Keyword(s):  
Neutron Stars ◽  
Nuclear Matter ◽  
Body Problem ◽  
Mean Field Theory ◽  
Mean Field ◽  
Compression Modulus ◽  
Baryon Number ◽  
Many Body ◽  
Relativistic Mean Field

For the nuclear many body problem at high densities, formulated in the framework of a relativistic mean-field theory, we investigate in detail the compression modulus of nuclear matter as a function of the effective nucleon mass. We include consistently in our modelling chemical equilibrium as well as baryon number and electric charge conservation and investigate properties of neutron stars. Among other predictions we focus on the dependence of the maximum mass of a sequence of neutron stars as a function of the compression modulus and the nucleon effective mass.

scholarly journals Quark-meson coupling model, nuclear matter constraints, and neutron star properties

2014 ◽  
Vol 89 (6) ◽  
Author(s):  
D. L. Whittenbury ◽  
J. D. Carroll ◽  
A. W. Thomas ◽  
K. Tsushima ◽  
J. R. Stone
Keyword(s):  
Neutron Star ◽  
Nuclear Matter ◽  
Coupling Model ◽  
Meson Coupling

scholarly journals Astrometric observations of neutron stars

2012 ◽  
Vol 8 (S289) ◽  
pp. 82-82
Author(s):  
Shami Chatterjee
Keyword(s):  
Neutron Star ◽  
Neutron Stars ◽  
Gamma Ray ◽  
Radio Pulse ◽  
Focal Plane Arrays ◽  
Yield Model ◽  
Long Baseline ◽  
Wide Range ◽  
Pulse Timing ◽  
Supernova Explosions

AbstractAstrometric observations of neutron stars have been conducted with a variety of techniques and over a wide range of wavelengths, ranging from radio-pulse timing and Very Long Baseline Interferometry to optical and X-ray imaging. Here I review the techniques and scientific goals behind recent high-precision neutron-star astrometry. Such measurements can yield model-independent distances and velocities that can be exploited, for example, to locate neutron-star birth sites, establish reference-frame ties, model the Galactic electron-density distribution, and constrain the astrophysics of supernova explosions. Recently, the Fermi gamma-ray space telescope has identified several highly luminous recycled pulsars, and precise measurement of their distances is of paramount importance to understand their energetics and astrophysics. The ongoing science returns from precision astrometry will continue in the long term with improvements in technology such as focal-plane arrays and synergies with new telescopes such as Gaia and the Square Kilometer Array.

scholarly journals Thermal properties of hot and dense matter: Influence of rapid rotation on protoneutron stars, hot neutron stars, and neutron star merger remnants

2021 ◽  
Vol 252 ◽  
pp. 05004
Author(s):  
Polychronis Koliogiannis ◽  
Charalampos Moustakidis
Keyword(s):  
Neutron Star ◽  
Equation Of State ◽  
Neutron Stars ◽  
Nuclear Matter ◽  
Equations Of State ◽  
Interaction Model ◽  
Dense Matter ◽  
Baryon Density ◽  
Dense Nuclear Matter ◽  
Protoneutron Stars

The knowledge of the equation of state is a key ingredient for many dynamical phenomena that depend sensitively on the hot and dense nuclear matter, such as the formation of protoneutron stars and hot neutron stars. In order to accurately describe them, we construct equations of state at FInite temperature and entropy per baryon for matter with varying proton fractions. This procedure is based on the momentum dependent interaction model and state-of-the-art microscopic data. In addition, we investigate the role of thermal and rotation effects on microscopic and macroscopic properties of neutron stars, including the mass and radius, the frequency, the Kerr parameter, the central baryon density, etc. The latter is also connected to the hot and rapidly rotating remnant after neutron star merger. The interplay between these quantities and data from late observations of neutron stars, both isolated and in matter of merging, could provide useful insight and robust constraints on the equation of state of nuclear matter.

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