The r-mode instability in strange stars with a crystalline crust

Abstract

The r-mode instability, believed to limit the rotation speed of compact stars, can provide empirical confirmation for the existence of stable deconfined phases of quark matter that are predicted by weak coupling calculations in Quantum Chromodynamics. We construct a model for strange quark stars as heavy as 2 solar masses that are made of superconducting quark matter in the bulk and a thin crystalline quark matter crust. This crystalline quark crust is sufficiently robust to withstand r-mode heating and viscous rubbing for realistic mode amplitudes O(10^{-2}), unlike a crust made of neutron-rich nuclei. The dissipation provided by viscous rubbing at the core-crust boundary is both necessary and sufficient to obtain stable rotation speeds that are consistent with the majority of rapidly spinning pulsars in low mass X-ray binaries. Our analysis implies that while bare strange stars are ruled out by the existence of rapidly spinning pulsars, a strange star with a quark matter crust is a distinct possibility.

4 pages, 1 figure

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Cited by in corpus (12)

• EMMI Rapid Reaction Task Force Meeting on 'Quark Matter in Compact Star'
• Fast spinning strange stars: possible ways to constrain interacting quark matter parameters
• Non-radial Oscillation Modes of Compact Stars with a Crust
• Instability windows and evolution of rapidly rotating neutron stars
• Properties of High-Density Matter in Neutron Stars
• Two-layer compact stars with crystalline quark matter: Screening effect on the tidal deformability
• Electromagnetic signals from bare strange stars
• Torsional oscillations of nonbare strange stars
• Recent progresses in strange quark stars
• R-mode instability of strange stars and observations of neutron stars in LMXBs
• Oscillation Modes of Strange Quark Stars with a Strangelet Crust
• The shear viscosity of two-flavor crystalline color superconducting quark matter