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Title: Disk-induced Binary Precession: Implications for Dynamics and Multimessenger Observations of Black Hole Binaries
Abstract Many studies have recently documented the orbital response of eccentric binaries accreting from thin circumbinary disks, characterizing the change in the binary semimajor axis and eccentricity. We extend these calculations to include the precession of the binary’s longitude of periapse induced by the circumbinary disk, and we characterize this precession continuously with binary eccentricityebfor equal mass components. This disk-induced apsidal precession is prograde with a weak dependence on the binary eccentricity wheneb≲ 0.4 and decreases approximately linearly foreb≳ 0.4; yet at allebbinary precession is faster than the rates of change to the semimajor axis and eccentricity by an order of magnitude. We estimate that such precession effects are likely most important for subparsec separated binaries with masses ≲107M⊙, like LISA precursors. We find that accreting, equal-mass LISA binaries withM< 106M⊙(and the most massiveM∼ 107M⊙binaries out toz∼ 3) may acquire a detectable phase offset due to the disk-induced precession. Moreover, disk-induced precession can compete with general relativistic precession in a vacuum, making it important for observer-dependent electromagnetic searches for accreting massive binaries—like Doppler boost and binary self-lensing models—after potentially only a few orbital periods.  more » « less
Award ID(s):
2206299
PAR ID:
10537736
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
964
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
46
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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