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Equilibrium configurations for quark-diquark stars and the problem of Her X-1 mass

J. E. Horvath·J. A. de Freitas Pacheco
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Abstract

We report new calculations of the physical properties of a quark-diquark plasma. A vacuum contribution is taken into account and is responsible for the appearance of a stable state at zero pressure and at a baryon density of about 2.2 times the nuclear matter density in this model. The resulting equation of state was used to integrate numerically the Tolman-Oppenheimer-Volkoff equations. The mass-radius relationship has been derived from a series of equilibrium configurations constituted by a mixture of quarks and diquarks. These stellar models, which are representative of a whole class, may be helpful to understand the possible compactness of the X-ray source Her X-1 and related objects.

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J. E. Horvath, J. A. de Freitas Pacheco. 1996-11-20. Equilibrium configurations for quark-diquark stars and the problem of Her X-1 mass. https://doi.org/10.1142/s0218271898000036

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