Constraining light dark photons from GW190517_055101 and GW190426_152155

Abstract

Ultralight dark photons predicted in several Standard Model extensions can trigger the superradiant instability around rotating black holes (BHs) if their Compton wavelength is comparable to the BH radius. Consequently, the angular momentum of the BH is reduced to a value which depends upon the mass and spin of the BH as well as the mass of the dark photon. We use the mass and spin measurements of the primary BHs in two recently observed blackhole binary (BBH) systems, GW190517_055101 and GW190426_152155, to constrain dark photon mass in the ranges 1.7x10(-14) eV < m(A') < 7.6x10(-13) eV and 1.3 x 10(-13) eV < m(A ') < 4.2 x 10(-12) eV, respectively, assuming a timescale of a few million years from the time of formation of the BBH system to the time of their merger. We also discuss an interesting x-ray binary system, MAXI J1820_070, albeit with a relatively small value of the spin parameter.