ISOVECTOR COMPONENTS OF LIGHT SCALAR MESON AND NUCLEAR MATTER PROPERTIES

2007 ◽  
Vol 16 (09) ◽  
pp. 2867-2871 ◽  
Author(s):  
C. A. Z. VASCONCELLOS ◽  
E. LÜTZ ◽  
M. RAZEIRA ◽  
B. E. J. BODMANN ◽  
M. DILLIG ◽  
...  
Keyword(s):  
Nuclear Matter ◽  
Scalar Meson ◽  
Mean Field ◽  
Symmetry Transformation ◽  
Hadronic Matter ◽  
Meson Field ◽  
Field Approach ◽  
Relativistic Mean Field ◽  
Light Scalar ◽  
Scalar Meson Field

We have predicted (contribution to this issue) an isovector component of the light scalar meson sector by using the chiral symmetry transformation formalism. On the basis of this result, we study dense hadronic matter in a generalized relativistic mean field approach with σ, ω and ρ mesons as well as nonlinear self-couplings of the I = 1 component of a light scalar meson field and compare its predictions for neutron star properties with results from different models for nuclear matter found in the literature.

SIGNATURES OF ISOVECTOR COMPONENTS OF A LIGHT SCALAR MESON IN PULSARS

2007 ◽  
Vol 16 (02n03) ◽  
pp. 373-380
Author(s):  
EDUARDO LÜTZ ◽  
MOISÉS RAZEIRA ◽  
BARDO E. J. BODMANN ◽  
CÉSAR A. ZEN VASCONCELLOS
Keyword(s):  
Neutron Star ◽  
Scalar Meson ◽  
Mean Field ◽  
Symmetry Transformation ◽  
Hadronic Matter ◽  
Meson Field ◽  
Field Approach ◽  
Relativistic Mean Field ◽  
Light Scalar ◽  
Scalar Meson Field

In a previous work, we have predicted an isovector component of the light scalar meson sector by using the chiral symmetry transformation formalism. On the basis of this result, we study dense hadronic matter in a generalized relativistic mean field approach with σ, ω and ρ mesons as well as nonlinear self-couplings of the I = 1 component of a light scalar meson field and compare its predictions for neutron star properties and with results from different models for nuclear matter found in the literature.

NONLINEAR σ, δ DERIVATIVE SELF-COUPLINGS IN A RMFT FOR NEUTRON STARS

2004 ◽  
Vol 13 (07) ◽  
pp. 1485-1491 ◽  
Author(s):  
SÉRGIO S. ROCHA ◽  
MOISÉS RAZEIRA ◽  
CÉSAR A. Z. VASCONCELLOS ◽  
MANFRED DILLIG
Keyword(s):  
Neutron Stars ◽  
Nuclear Matter ◽  
Mean Field ◽  
Hadronic Matter ◽  
Field Approach ◽  
Relativistic Mean Field ◽  
Global Properties ◽  
Substantial Modification ◽  
Nonlinear Couplings

We study dense hadronic matter in a generalized relativistic mean field approach which contains nonlinear couplings of the σ, ω, ϱ, δ fields and compare its predictions for properties of neutron stars with the corresponding results from different models found in the literature. Our predictions indicate a substantial modification in static global properties of nuclear matter and neutron stars with the inclusion of the δ meson into the formalism.

THE ROLE OF SELF-COUPLINGS OF SCALAR MESONS IN NEUTRON STAR MATTER

2002 ◽  
Vol 17 (21) ◽  
pp. 1335-1344 ◽  
Author(s):  
S. S. POCHA ◽  
A. R. TAURINES ◽  
C. A. Z. VASCONCELLOS ◽  
M. B. PINTO ◽  
M. DILLIG
Keyword(s):  
Neutron Star ◽  
Nuclear Matter ◽  
Degrees Of Freedom ◽  
Scalar Meson ◽  
Dense Matter ◽  
Meson Field ◽  
Static Properties ◽  
Hartree Approximation ◽  
Scalar Meson Field

The influence of nonlinear cubic and quartic self-couplings of the scalar meson field in nuclear matter is investigated. In summing the leading tadpole corrections for the Dirac-vacuum, we compare two approaches, the modified relativistic Hartree approximation, applied to the Walecka model, and the relativistic Hartree approximation, employed to the nonlinear model, respectively. These two approaches render similar expressions for the equation of state of nuclear matter up to the fifth order in the scalar meson field. We find that, by exploring the parameter dependence of the two models, they yield similar results for the bulk static properties of nuclear matter. However, increasing the baryon density the two models start to deviate significantly, such as in the predictions for the maximal mass of a neutron star or in the role of hyperon degrees of freedom in dense matter. The results indicate that with increasing density, scalar meson self-couplings beyond the fourth order seem to play a significant role.

SIGNATURES OF ISOVECTOR COMPONENTS OF THE SCALAR σ-MESON IN NEUTRON STARS

2004 ◽  
Vol 13 (07) ◽  
pp. 1255-1259 ◽  
Author(s):  
EDUARDO LÜTZ ◽  
MOISÉS RAZEIRA ◽  
CÉSAR A. Z. VASCONCELLOS ◽  
MANFRED DILLIG
Keyword(s):  
Neutron Star ◽  
Scalar Field ◽  
Neutron Stars ◽  
Mean Field ◽  
Hadronic Matter ◽  
Field Approach ◽  
Relativistic Mean Field ◽  
Intermediate States

Based on non-crossed, crossed and correlated ππ exchanges with irreducible N, Δ intermediate states, we predict an isovector component for the σ meson. We study dense hadronic matter in a generalized relativistic mean field approach with nonlinear self-couplings of the I=0,1 components of the scalar field and compare its predictions for neutron star properties with results from different models found in the literature.

NEUTRON STARS WITH PARAMETRIZED MESON COUPLINGS

2000 ◽  
Vol 15 (29) ◽  
pp. 1789-1800 ◽  
Author(s):  
A. R. TAURINES ◽  
C. A. Z. VASCONCELLOS ◽  
M. MALHEIRO ◽  
M. CHIAPPARINI
Keyword(s):  
Neutron Stars ◽  
Nuclear Matter ◽  
Degrees Of Freedom ◽  
Scalar Meson ◽  
Mean Field Theory ◽  
Mean Field ◽  
Static Properties ◽  
Relativistic Mean Field ◽  
Specific Choice

We investigate static properties of nuclear and neutron star matter by using a relativistic mean field theory with parametrized couplings. With a suitable choice of mathematical parameters, the couplings allow one to reproduce results of current quantum hadrodynamics models. For other parametrizations, a better description of bulk properties of nuclear matter is obtained. The formalism is extended to include hyperon and lepton degrees of freedom, and an analysis on the effects of the phenomenological couplings in the fermion populations and mass of neutron stars is performed. The results show a strong similarity between the predictions of ZM-like models and those with exponential couplings. We have observed in particular an extreme sensibility of the predictions of these theories on the specific choice of the values of the binding energy of nuclear matter and saturation density. Additionally, the role of the very intense scalar meson mean field found in the interior of neutron stars in the screening of the nucleon mass is discussed.

MIRROR NUCLEI 12B AND 12N IN TIME-ODD TRIAXIAL RELATIVISTIC MEAN FIELD THEORY

2006 ◽  
Vol 15 (07) ◽  
pp. 1513-1521
Author(s):  
H. CHEN ◽  
H. MEI ◽  
J. MENG ◽  
J. M. YAO
Keyword(s):  
Field Theory ◽  
Mass Difference ◽  
Mean Field Theory ◽  
Mean Field ◽  
Coulomb Field ◽  
Meson Field ◽  
Relativistic Mean Field Theory ◽  
Nuclear Magnetism ◽  
Field Approach ◽  
Relativistic Mean Field

Properties of the odd-odd mirror nuclei 12 B and 12 N have been investigated in the time-odd triaxial relativistic mean field approach. Influences of the nuclear magnetism, the mass difference between neutron and proton, the isovector meson field ρ and the Coulomb field on the properties of mirror nuclei have been discussed in detail.

scholarly journals Spinodal instabilities in nuclear matter in a stochastic relativistic mean-field approach

2009 ◽  
Vol 80 (3) ◽  
Author(s):  
S. Ayik ◽  
O. Yilmaz ◽  
N. Er ◽  
A. Gokalp ◽  
P. Ring
Keyword(s):  
Nuclear Matter ◽  
Mean Field ◽  
Field Approach ◽  
Relativistic Mean Field
Sign in / Sign up

Export Citation Format

Share Document