language: en

arXiv:0811.1219v2 [astro-ph] 30 Jun 2009

[Mon. Not. R. Astron. Soc. 000, 1?7 (2008)]

Printed 30 June 2009

(MN L A T E X style file v2.2)

The growth of supermassive black holes in pseudo-bulges, classical bulges and elliptical galaxies

Dimitri A. Gadotti ? and Guinevere Kauffmann
Max-Planck-Institut für Astrophysik,
Karl-Schwarzschild-Str. 1, D-85748 Garching bei München, Germany
30 June 2009

ABSTRACT Using results from structural analysis of a sample of nearly 1000 local galaxies from the Sloan Digital Sky Survey, we estimate how the mass in central black holes is distributed amongst elliptical galaxies, classical bulges and pseudo-bulges, and investigate the relation between their stellar masses and central stellar velocity dispersion ?. Assuming a single relation between elliptical galaxy/bulge mass, M Bulge , and central black hole mass, M BH , we find that 55 +8 ?4 per cent of the mass in black holes in the local universe is in the centres of elliptical galaxies, 41 +4 ?2 per cent in classical bulges and 4 +0.9 ?0.4 per cent in pseudo-bulges. We find that ellipticals, classical bulges and pseudo-bulges follow different relations between their stellar masses and ?, and the most significant offset occurs for pseudo-bulges in barred galaxies. This structural dissimilarity leads to discrepant black hole masses if single M BH ? M Bulge and M BH ? ? relations are used. Adopting relations from the literature, we find that the M BH ? ? relation yields an estimate of the total mass density in black holes that is roughly 55 per cent larger than if the M BH ? M Bulge relation is used.

Key words: galaxies: bulges ? galaxies: evolution ? galaxies: formation ? galaxies: fundamental parameters ? galaxies: kinematics and dynamics ? galaxies: photometry

1 INTRODUCTION