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arXiv · 2005.09728

Core collapse in massive scalar-tensor gravity

Roxana Rosca-Mead·Ulrich Sperhake·Christopher J. Moore·Michalis Agathos·Davide Gerosa·Christian D. Ott
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Abstract

This paper provides an extended exploration of the inverse-chirp gravitational-wave signals from stellar collapse in massive scalar-tensor gravity reported in [Phys. Rev. Lett. {\bf 119}, 201103]. We systematically explore the parameter space that characterizes the progenitor stars, the equation of state and the scalar-tensor theory of the core collapse events. We identify a remarkably simple and straightforward classification scheme of the resulting collapse events. For any given set of parameters, the collapse leads to one of three end states, a weakly scalarized neutron star, a strongly scalarized neutron star or a black hole, possibly formed in multiple stages. The latter two end states can lead to strong gravitational-wave signals that may be detectable in present continuous-wave searches with ground-based detectors. We identify a very sharp boundary in the parameter space that separates events with strong gravitational-wave emission from those with negligible radiation.

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Roxana Rosca-Mead, Ulrich Sperhake, Christopher J. Moore, Michalis Agathos, Davide Gerosa, Christian D. Ott. 2020-09-15. Core collapse in massive scalar-tensor gravity. https://doi.org/10.1103/physrevd.102.044010

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