The merger of two galaxies, each hosting a supermassive black hole (SMBH) of mass 10^{6}
Supermassive black hole binary systems (SMBHBs) should be the most powerful sources of gravitational waves (GWs) in the universe. Once pulsar timing arrays (PTAs) detect the stochastic GW background from their cosmic merger history, searching for individually resolvable binaries will take on new importance. Since these individual SMBHBs are expected to be rare, here we explore how strong gravitational lensing can act as a tool for increasing their detection prospects by magnifying fainter sources and bringing them into view. Unlike for electromagnetic waves, when the geometric optics limit is nearly always valid, for GWs the wavediffractioninterference effects can become important when the wavelength of the GWs is larger than the Schwarzchild radius of the lens, i.e.,
 NSFPAR ID:
 10462151
 Publisher / Repository:
 DOI PREFIX: 10.3847
 Date Published:
 Journal Name:
 The Astrophysical Journal
 Volume:
 955
 Issue:
 1
 ISSN:
 0004637X
 Format(s):
 Medium: X Size: Article No. 25
 Size(s):
 ["Article No. 25"]
 Sponsoring Org:
 National Science Foundation
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