Strangeness content of neutron stars with strong Σ--hyperon repulsion

M. Razeira; A. Mesquita; C.A.Z. Vasconcellos; R. Ruffini; J.A. Rueda; R.O. Gomes

doi:10.1002/asna.201412102

Strangeness content of neutron stars with strong Σ--hyperon repulsion

Astronomische Nachrichten ◽

10.1002/asna.201412102 ◽

2014 ◽

Vol 335 (6-7) ◽

pp. 739-744

Author(s):

M. Razeira ◽

A. Mesquita ◽

C.A.Z. Vasconcellos ◽

R. Ruffini ◽

J.A. Rueda ◽

...

Keyword(s):

Neutron Stars ◽

Strangeness Content

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Interplay between the symmetry energy and the strangeness content of neutron stars

Physical Review C ◽

10.1103/physrevc.87.055801 ◽

2013 ◽

Vol 87 (5) ◽

Cited By ~ 38

Author(s):

Constança Providência ◽

Aziz Rabhi

Keyword(s):

Neutron Stars ◽

Symmetry Energy ◽

Strangeness Content

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STABILITY OF NEUTRON STARS WITH LARGE AMOUNT OF STRANGENESS AND THE ROLE OF δ-MESON

International Journal of Modern Physics E ◽

10.1142/s0218301307008574 ◽

2007 ◽

Vol 16 (09) ◽

pp. 2855-2858 ◽

Cited By ~ 3

Author(s):

M. RAZEIRA ◽

A. MESQUITA ◽

C. A. Z. VASCONCELLOS ◽

B. E. J. BODMANN ◽

M. DILLIG ◽

...

Keyword(s):

Neutron Star ◽

Equation Of State ◽

Neutron Stars ◽

Nuclear Matter ◽

Lagrangian Density ◽

Stability Conditions ◽

Meson Field ◽

Strange Quarks ◽

Strangeness Content

We investigate the role of the strange σ*, ϕ and δ meson fields on the delineation of main properties of neutron stars using a parameterized Lagrangian density model in the effective baryon and meson sectors. We assume, strange quarks are localized within the hyperon fields, which carry the strangeness content of the model. Our main goal is to analyze stability conditions of neutron stars with large amount of strangeness per baryon. Our main result indicates the inclusion of the strange (anti-)quark containing meson field σ*, besides ϕ and δ into nuclear matter, turn the equation of state stiffer this way increasing the gravitational mass of the neutron star.

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STABILITY OF NEUTRON STARS WITH A LARGE AMOUNT OF STRANGENESS

International Journal of Modern Physics D ◽

10.1142/s0218271807010110 ◽

2007 ◽

Vol 16 (02n03) ◽

pp. 347-356

Author(s):

MOISES RAZEIRA ◽

BARDO E. J. BODMANN ◽

CÉSAR A. ZEN VASCONCELLOS ◽

ALEXANDRE MESQUITA

Keyword(s):

Neutron Star ◽

Equation Of State ◽

Neutron Stars ◽

Nuclear Matter ◽

Lagrangian Density ◽

Stability Conditions ◽

Strange Quarks ◽

Strange Meson ◽

Strangeness Content

We investigate the role of the strange σ* and ϕ meson fields on the delineation of the main properties of neutron stars using a parameterized Lagrangian density model in the effective baryon and meson sectors. We assume strange quarks are localized within the hyperon fields which carry the strangeness content of the model. Our main goal is to analyze stability conditions of neutron stars with a large amount of strangeness per baryon. Our main result indicates the inclusion of the strange meson fields σ* and ϕ into nuclear matter make the equation of state stiffer thereby increasing the gravitational mass of the neutron star.

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THE EFFECT OF THE SCALAR-ISOVECTOR MESON FIELD ON HYPERON-RICH NEUTRON STAR MATTER

International Journal of Modern Physics E ◽

10.1142/s0218301308010477 ◽

2008 ◽

Vol 17 (07) ◽

pp. 1293-1307 ◽

Cited By ~ 1

Author(s):

AI-JUN MI ◽

WEI ZUO ◽

ANG LI

Keyword(s):

Neutron Star ◽

Neutron Stars ◽

Mean Field Theory ◽

Mean Field ◽

Maximum Mass ◽

Meson Field ◽

Neutron Star Matter ◽

Relativistic Mean Field ◽

Strangeness Content ◽

Positively Charged

We investigate the effect of the scalar-isovector δ-meson field on the equation of state (EOS) and composition of hyperonic neutron star matter, and the properties of hyperonic neutron stars within the framework of the relativistic mean field theory. The influence of the δ-field turns out to be quite different and generally weaker for hyperonic neutron star matter as compared to that for npeμ neutron star matter. We find that inclusion of the δ-field enhances the strangeness content slightly and consequently moderately softens the EOS of neutron star matter in its hyperonic phase. As for the composition of hyperonic star matter, the effect of the δ-field is shown to shift the onset of the negatively-charged (positively-charged) hyperons to slightly lower (higher) densities and to enhance (reduce) their abundances. The influence of the δ-field on the maximum mass of hyperonic neutron stars is found to be fairly weak, whereas inclusion of the δ-field turns out to enhance sizably both the radii and the moments of inertia of neutron stars with given masses. It is also shown that the effects of the δ-field on the properties of hyperonic neutron stars remain similar in the case of switching off the Σ hyperons.

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