A DISPLACED SUPERMASSIVE BLACK HOLE IN M87

Batcheldor, D, Robinson, A, Axon, D J, Perlman, E S and Merritt, D (2010) A DISPLACED SUPERMASSIVE BLACK HOLE IN M87. Astrophysical Journal Letters, 717 (1). L6-L10. ISSN 2041-8205

[img]
Preview
PDF - Published Version
Download (386kB) | Preview

Abstract

Isophotal analysis of M87, using data from the Advanced Camera for Surveys, reveals a projected displacement of 6.8 +/- 0.8 pc (similar to 0 ''.1) between the nuclear point source (presumed to be the location of the supermassive black hole, SMBH) and the photo-center of the galaxy. The displacement is along a position angle of 307 degrees +/- 17 degrees and is consistent with the jet axis. This suggests the active SMBH in M87 does not currently reside at the galaxy center of mass, but is displaced in the counter-jet direction. Possible explanations for the displacement include orbital motion of an SMBH binary, gravitational perturbations due to massive objects ( e. g., globular clusters), acceleration by an asymmetric or intrinsically one-sided jet, and gravitational recoil resulting from the coalescence of an SMBIIbinary. The displacement direction favors the latter two mechanisms. However, jet asymmetry is only viable, at the observed accretion rate, for a jet age of >0.1 Gyr and if the galaxy restoring force is negligible. This could be the case in the low-density core of M87. A moderate recoil similar to 1Myr ago might explain the disturbed nature of the nuclear gas disk, could be aligned with the jet axis, and can produce the observed offset. Alternatively, the displacement could be due to residual oscillations resulting from a large recoil that occurred in the aftermath of a major merger <= 1 Gyr ago.

Item Type: Article
Schools and Departments: School of Mathematical and Physical Sciences > Physics and Astronomy
Depositing User: David Axon
Date Deposited: 06 Feb 2012 19:22
Last Modified: 07 Mar 2017 06:13
URI: http://sro.sussex.ac.uk/id/eprint/20289

View download statistics for this item

📧 Request an update