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arXiv · 2205.03283

Universal relations for quasinormal modes of neutron stars in $R^2$ gravity

J. L. Blázquez-Salcedo·L. M. González-Romero·F. S. Khoo·J. Kunz·V. Preut
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Abstract

We construct quasinormal modes for neutron stars in $R^2$ gravity in the Einstein frame, considering scalar masses in the sub-neV range. In particular, we investigate the fundamental quadrupole fluid f-modes and the dipole fluid F-modes. Employing six equations of state covering matter content with nucleons, hyperons, and quarks, we then propose universal relations for the quadrupole f-modes and dipole F-modes. The dipole F-modes are ultra-long lived and, for the lower scalar masses, their frequencies are inversely proportional to the corresponding Compton wavelength.

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J. L. Blázquez-Salcedo, L. M. González-Romero, F. S. Khoo, J. Kunz, V. Preut. 2022-05-06. Universal relations for quasinormal modes of neutron stars in $R^2$ gravity. https://doi.org/10.1103/physrevd.106.044007

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