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arXiv · 2410.23839

Hair is complicated: Gravitational waves from stable and unstable boson-star mergers

Bo-Xuan Ge·Eugene A. Lim·Ulrich Sperhake·Tamara Evstafyeva·Daniela Cors·Eloy de Jong·Robin Croft·Thomas Helfer
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Abstract

We explore the gravitational-wave emission from head-on collisions of equal-mass solitonic boson-star binaries from simulations spanning a two-dimensional parameter space, consisting of the central scalar-field amplitude of the stars and the solitonic potential parameter. We report the gravitational-wave energies emitted by boson-star binaries which, due to their combination of moderately high compactness with significant deformability, we often find to be louder by up to an order of magnitude than analogous black-hole collisions. The dependence of the radiated energy on the boson-star parameters exhibits striking needle-sharp features and discontinuous jumps to the value emitted by black-hole binaries. We explain these features in terms of the solitonic potential and the stability properties of the respective individual stars.

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Bo-Xuan Ge, Eugene A. Lim, Ulrich Sperhake, Tamara Evstafyeva, Daniela Cors, Eloy de Jong, Robin Croft, Thomas Helfer. 2024-10-31. Hair is complicated: Gravitational waves from stable and unstable boson-star mergers. https://doi.org/10.1103/2dhs-phl4

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