The tidal disruption of stars by supermassive black holes (SMBHs) probes relativistic gravity. In the coming decade, the number of observed tidal disruption events (TDEs) will grow by several orders of magnitude, allowing statistical inferences of the properties of the SMBH and stellar populations. Here we analyze the probability distribution functions of the pericenter distances of stars that encounter an SMBH in the Schwarzschild geometry, where the results are completely analytic, and the Kerr metric. From this analysis we calculate the number of observable TDEs, defined to be those that come within the tidal radius
Gravitationalwave (GW) detections of merging neutron star–black hole (NSBH) systems probe astrophysical neutron star (NS) and black hole (BH) mass distributions, especially at the transition between NS and BH masses. Of particular interest are the maximum NS mass, minimum BH mass, and potential mass gap between them. While previous GW population analyses assumed all NSs obey the same maximum mass, if rapidly spinning NSs exist, they can extend to larger maximum masses than nonspinning NSs. In fact, several authors have proposed that the ∼2.6
 Award ID(s):
 1944412
 Publication Date:
 NSFPAR ID:
 10372294
 Journal Name:
 The Astrophysical Journal
 Volume:
 937
 Issue:
 2
 Page Range or eLocationID:
 Article No. 73
 ISSN:
 0004637X
 Publisher:
 DOI PREFIX: 10.3847
 Sponsoring Org:
 National Science Foundation
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