RELATIVISTIC MERGERS OF SUPERMASSIVE BLACK HOLES AND THEIR ELECTROMAGNETIC SIGNATURES

Journal Article · Tue Jun 01 00:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/715/2/1117· OSTI ID:21450920

Bode, Tanja; Haas, Roland; Laguna, Pablo; Shoemaker, Deirdre ^[1]; Bogdanovic, Tamara ^[2]

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1. Center for Relativistic Astrophysics, School of Physics, Georgia Institute of Technology, Atlanta, GA 30332 (United States)
2. Department of Astronomy, University of Maryland, College Park, MD 207422 (United States)

Coincident detections of electromagnetic (EM) and gravitational wave (GW) signatures from coalescence events of supermassive black holes (SMBHs) are the next observational grand challenge. Such detections will provide the means to study cosmological evolution and accretion processes associated with these gargantuan compact objects. More generally, the observations will enable testing general relativity in the strong, nonlinear regime and will provide independent cosmological measurements to high precision. Understanding the conditions under which coincidences of EM and GW signatures arise during SMBH mergers is therefore of paramount importance. As an essential step toward this goal, we present results from the first fully general relativistic, hydrodynamical study of the late inspiral and merger of equal-mass, spinning SMBH binaries in a gas cloud. We find that variable EM signatures correlated with GWs can arise in merging systems as a consequence of shocks and accretion combined with the effect of relativistic beaming. The most striking EM variability is observed for systems where spins are aligned with the orbital axis and where orbiting black holes form a stable set of density wakes, but all systems exhibit some characteristic signatures that can be utilized in searches for EM counterparts. In the case of the most massive binaries observable by the Laser Interferometer Space Antenna, calculated luminosities imply that they may be identified by EM searches to z {approx} 1, while lower mass systems and binaries immersed in low density ambient gas can only be detected in the local universe.

• OSTI ID: 21450920
• Journal Information: Astrophysical Journal, Vol. 715, Issue 2; Other Information: DOI: 10.1088/0004-637X/715/2/1117; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BLACK HOLES
COALESCENCE
GALACTIC EVOLUTION
GALAXY NUCLEI
GENERAL RELATIVITY THEORY
GRAVITATIONAL WAVES
INTERFEROMETERS
LUMINOSITY
MASS
RELATIVISTIC RANGE
UNIVERSE
ENERGY RANGE
EVOLUTION
FIELD THEORIES
MEASURING INSTRUMENTS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
RELATIVITY THEORY