Investigation of the existence of hybrid stars using Nambu-Jona-Lasinio models

Abstract

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.

4 pages, 2 figures; prepared for IV International Workshop on Astronomy and Relativistic Astrophysics (IWARA 2009), Maresias, 4-8 Oct 2009

References in corpus (3)

• Modern compact star observations and the quark matter equation of state
• Quark matter in neutron stars within the Nambu - Jona-Lasinio model and confinement
• Ultra-Dense Neutron Star Matter, Strange Quark Stars, and the Nuclear Equation of State

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• Model of hybrid star with baryonic and strange quark matter in Tolman-Kuchowicz spacetime
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