Ultralonglived quasinormal modes of neutron stars in massive scalartensor gravity
Abstract
The spectrum of frequencies and characteristic times that compose the ringdown phase of gravitational waves emitted by neutron stars carries information about the matter content (the equation of state) and the underlying theory of gravity. Typically, modified theories of gravity introduce additional degrees of freedom/fields, such as scalars, which result in new families of modes composing the ringdown spectrum. Simple but physically promising candidates are scalartensor theories, which effectively introduce an additional massive scalar field (i.e., an ultralight boson) that couples nonminimally to gravity, resulting in scalarized neutron stars. Here we present the first calculation of the full ringdown spectrum in such theories. We show that the ringdown spectrum of neutron stars with ultralight bosons is much richer and fundamentally different from the spectrum in general relativity and that it possesses propagating ultralonglived modes.
 Publication:

EPL (Europhysics Letters)
 Pub Date:
 June 2020
 DOI:
 10.1209/02955075/130/50002
 arXiv:
 arXiv:2001.09117
 Bibcode:
 2020EL....13050002L
 Keywords:

 04.40.Dg;
 04.50.Kd;
 04.30.w;
 General Relativity and Quantum Cosmology;
 Astrophysics  High Energy Astrophysical Phenomena
 EPrint:
 7 pages, 3 figures. v2: Generalisation of the results to generic massive scalartensor gravity