Surface gravity of neutron stars and strange stars
نویسندگان
چکیده
The upper bound on the value of the surface gravity, gs, for neutron stars with equations of state respecting vsound ≤ c, is derived. This bound is inversely proportional to the maximum allowable mass Mmax, and it reads gs ≤ 1.411× 10 15 (Mmax/M⊙) −1 cm s. It implies an absolute upper bound 7.4× 10 cm s if one uses the 2σ lower bound on the neutron mass measured recently in 4U1700-37, 1.9M⊙. A correlation between gs and the compactness parameter 2GM/Rc for baryonic stars is analyzed. The properties of gs of strange quark stars and its upper bounds are discussed using the scaling properties of the strange-star models.
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تاریخ انتشار 2004