In September 2020, Advanced LIGO-Virgo reported a short gravitational-wave signal (GW190521) interpreted as a quasi-circular merger of black holes, one at least populating the pair-instability supernova gap. In this talk I will show that GW190521 is consistent with numerically simulated signals from head-on collisions of two (equal mass and spin) horizonless vector boson stars (aka Proca stars) and provide estimate the mass of the corresponding ultralight vector boson. This provides the first demonstration of close degeneracy between these two theoretical models, for a real gravitational-wave event.
|First author||Juan Calderon Bustillo|
|Collaboration / Activity||LIGO Scientific Collaboration|