Extreme neutron stars from Extended Theories of Gravity
Abstract
We discuss neutron stars with strong magnetic mean fields in the framework of Extended Theories of Gravity. In particular, we take into account models derived from f(R) and f(G) extensions of General Relativity where functions of the Ricci curvature invariant R and the GaussBonnet invariant G are respectively considered. Dense matter in magnetic mean field, generated by magnetic properties of particles, is described by assuming a model with three meson fields and baryons octet. As result, the considerable increasing of maximal mass of neutron stars can be achieved by cubic corrections in f(R) gravity. In principle, massive stars with M > 4M{sub ☉} can be obtained. On the other hand, stable stars with high strangeness fraction (with central densities ρ{sub c} ∼ 1.5–2.0 GeV/fm{sup 3}) are possible considering quadratic corrections of f(G) gravity. The magnetic field strength in the star center is of order 6–8 × 10{sup 18} G. In general, we can say that other branches of massive neutron stars are possible considering the extra pressure contributions coming from gravity extensions. Such a feature can constitute both a probe for alternative theories and a way out to address anomalous selfgravitating compact systems.
 Authors:
 I. Kant Baltic Federal University, Institute of Physics and Technology, Nevskogo st. 14, Kaliningrad, 236041 (Russian Federation)
 Dipartimento di Fisica, Università di Napoli ''Federico II'', Via Cinthia, 9, Napoli, I80126 Italy (Italy)
 Instituciò Catalana de Recerca i Estudis Avançats (ICREA), Barcelona (Spain)
 Publication Date:
 OSTI Identifier:
 22382039
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 01; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BARYON OCTETS; CORRECTIONS; GENERAL RELATIVITY THEORY; GEV RANGE; GRAVITATION; MAGNETIC PROPERTIES; MEANFIELD THEORY; MESONS; NEUTRON STARS
Citation Formats
Astashenok, Artyom V., Capozziello, Salvatore, and Odintsov, Sergei D., Email: artyom.art@gmail.com, Email: capozziello@na.infn.it, Email: odintsov@ieec.uab.es. Extreme neutron stars from Extended Theories of Gravity. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/01/001.
Astashenok, Artyom V., Capozziello, Salvatore, & Odintsov, Sergei D., Email: artyom.art@gmail.com, Email: capozziello@na.infn.it, Email: odintsov@ieec.uab.es. Extreme neutron stars from Extended Theories of Gravity. United States. doi:10.1088/14757516/2015/01/001.
Astashenok, Artyom V., Capozziello, Salvatore, and Odintsov, Sergei D., Email: artyom.art@gmail.com, Email: capozziello@na.infn.it, Email: odintsov@ieec.uab.es. 2015.
"Extreme neutron stars from Extended Theories of Gravity". United States.
doi:10.1088/14757516/2015/01/001.
@article{osti_22382039,
title = {Extreme neutron stars from Extended Theories of Gravity},
author = {Astashenok, Artyom V. and Capozziello, Salvatore and Odintsov, Sergei D., Email: artyom.art@gmail.com, Email: capozziello@na.infn.it, Email: odintsov@ieec.uab.es},
abstractNote = {We discuss neutron stars with strong magnetic mean fields in the framework of Extended Theories of Gravity. In particular, we take into account models derived from f(R) and f(G) extensions of General Relativity where functions of the Ricci curvature invariant R and the GaussBonnet invariant G are respectively considered. Dense matter in magnetic mean field, generated by magnetic properties of particles, is described by assuming a model with three meson fields and baryons octet. As result, the considerable increasing of maximal mass of neutron stars can be achieved by cubic corrections in f(R) gravity. In principle, massive stars with M > 4M{sub ☉} can be obtained. On the other hand, stable stars with high strangeness fraction (with central densities ρ{sub c} ∼ 1.5–2.0 GeV/fm{sup 3}) are possible considering quadratic corrections of f(G) gravity. The magnetic field strength in the star center is of order 6–8 × 10{sup 18} G. In general, we can say that other branches of massive neutron stars are possible considering the extra pressure contributions coming from gravity extensions. Such a feature can constitute both a probe for alternative theories and a way out to address anomalous selfgravitating compact systems.},
doi = {10.1088/14757516/2015/01/001},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 01,
volume = 2015,
place = {United States},
year = 2015,
month = 1
}

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