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arXiv · 1708.05985

Non-radial Oscillation Modes of Compact Stars with a Crust

C. Vasquez Flores·Zack B. Hall II·Prashanth Jaikumar
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Abstract

Oscillation modes of isolated compact stars can, in principle, be a fingerprint of the equation of state (EoS) of dense matter. We study the non-radial high-frequency l=2 spheroidal modes of neutron stars and strange quark stars, adopting a two-component model (core and crust) for these two types of stars. Using perturbed fluid equations in the relativistic Cowling approximation, we explore the effect of a strangelet or hadronic crust on the oscillation modes of strange stars. The results differ from the case of neutron stars with a crust. In comparison to fluid-only configurations, we find that a solid crust on top of a neutron star increases the p-mode frequency slightly with little effect on the f-mode frequency, whereas for strange stars, a strangelet crust on top of a quark core significantly increases the f-mode frequency with little effect on the p-mode frequency.

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C. Vasquez Flores, Zack B. Hall II, Prashanth Jaikumar. 2017-08-20. Non-radial Oscillation Modes of Compact Stars with a Crust. https://doi.org/10.1103/physrevc.96.065803

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