beecee Posted October 4, 2017 Share Posted October 4, 2017 https://phys.org/news/2017-10-gravitational-detectors-dark.html Gravitational wave detectors could shed light on dark matter October 3, 2017 Schematic illustration of the cloud formed around a spinning black hole. The black hole loses energy E_S and angular momentum L_S through the growth of the cloud and emission of gravitational waves. Accretion of gas from the disk transports energy E_ACC and angular momentum L_ACC. The balance between these phenomena depends on the mass of the particles forming the cloud, and it determines whether the cloud can grow. Credit: University of Mississippi A global team of scientists, including two University of Mississippi physicists, has found that the same instruments used in the historic discovery of gravitational waves caused by colliding black holes could help unlock the secrets of dark matter, a mysterious and as-yet-unobserved component of the universe. Read more at: https://phys.org/news/2017-10-gravitational-detectors-dark.html#jCp <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> The paper: https://arxiv.org/pdf/1706.06311.pdf Gravitational wave searches for ultralight bosons with LIGO and LISA Abstract: Ultralight bosons can induce superradiant instabilities in spinning black holes, tapping their rotational energy to trigger the growth of a bosonic condensate. Possible observational imprints of these boson clouds include (i) direct detection of the nearly monochromatic (resolvable or stochastic) gravitational waves emitted by the condensate, and (ii) statistically significant evidence for the formation of “holes” at large spins in the spin versus mass plane (sometimes also referred to as “Regge plane”) of astrophysical black holes. In this work, we focus on the prospects of LISA and LIGO detecting or constraining scalars with mass in the range ms ∈ [10−19 , 10−15] eV and ms ∈ [10−14 , 10−11] eV, respectively. Using astrophysical models of black-hole populations and black-hole perturbation theory calculations of the gravitational emission, we find that LIGO could observe a stochastic background of gravitational radiation in the range ms ∈ [2 × 10−13 , 10−12] eV, and up to 104 resolvable events in a 4-year search if ms ∼ 3 × 10−13 eV. LISA could observe a stochastic background for boson masses in the range ms ∈ [5 × 10−19 , 5 × 10−16], and up to ∼ 103 resolvable events in a 4-year search if ms ∼ 10−17 eV. LISA could further measure spins for black-hole binaries with component masses in the range [103 , 107 ] M, which is not probed by traditional spin-measurement techniques. A statistical analysis of the spin distribution of these binaries could either rule out scalar fields in the mass range [4 × 10−18 , 10−14] eV, or measure ms with ten percent accuracy if light scalars in the mass range [10−17 , 10−13] eV exist. Link to comment Share on other sites More sharing options...
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