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Ultralight Bosonic Field Mass Bounds from Astrophysical Black Hole Spin

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 Added by Matthew J. Stott
 Publication date 2020
  fields Physics
and research's language is English




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Black Hole measurements have grown significantly in the new age of gravitation wave astronomy from LIGO observations of binary black hole mergers. As yet unobserved massive ultralight bosonic fields represent one of the most exciting features of Standard Model extensions, capable of providing solutions to numerous paradigmatic issues in particle physics and cosmology. In this work we explore bounds from spinning astrophysical black holes and their angular momentum energy transfer to bosonic condensates which can form surrounding the black hole via superradiant instabilities. Using recent analytical results we perform a simplified analysis with a generous ensemble of black hole parameter measurements where we find superradiance very generally excludes bosonic fields in the mass ranges; spin-0: ${scriptsize { 3.8times10^{-14} {rm eV} leq mu_0 leq 3.4times10^{-11} {rm eV}, 5.5times10^{-20} {rm eV} leq mu_0 leq 1.3times10^{-16} {rm eV}, 2.5times10^{-21} {rm eV} leq mu_0 leq 1.2times10^{-20} {rm eV}}}$, spin-1: ${scriptsize { 6.2times10^{-15} {rm eV} leq mu_1 leq 3.9times10^{-11} {rm eV}, 2.8times10^{-22} {rm eV} leq mu_1 leq 1.9times10^{-16} {rm eV} }}$ and spin-2: ${scriptsize { 2.2times10^{-14} {rm eV} leq mu_2 leq 2.8times10^{-11} {rm eV}, 1.8times10^{-20} {rm eV} leq mu_2 leq 1.8times10^{-16} {rm eV}, 6.4times10^{-22} {rm eV} leq mu_2 leq 7.7times10^{-21} {rm eV} }}$ respectively. We also explore these bounds in the context of specific phenomenological models, specifically the QCD axion, M-theory models and fuzzy dark matter sitting at the edges of current limits. In particular we include recent measurements of event GW190521 and M87* used to constrain both the masses and decay constants of axion like fields. Finally we comment a simple example of a spectrum of fields for the spin-0 and spin-1 cases.



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