The Millennium Galaxy Catalogue: The Mbh--Lspheroid derived supermassive black hole mass function

الأصل · EN

Supermassive black hole mass estimates are derived for 1743 galaxies from the Millennium Galaxy Catalogue using the recently revised empirical relation between supermassive black hole mass and the luminosity of the host spheroid. The MGC spheroid luminosities are based on R¹/ⁿ-bulge plus exponential-disc decompositions. The majority of black hole masses reside between 10⁶ M and an upper limit of 2×10⁹ M. Using previously determined space density weights, we derive the SMBH mass function which we fit with a Schechter-like function. Integrating the black hole mass function over 10⁶< Mbh/ M < 10¹⁰ gives a supermassive black hole mass density of (3.8 ± 0.6) × 10⁵ h³₇₀ M Mpc⁻³ for early-type galaxies and (0.96 ± 0.2) ×10⁵ h³₇₀ M Mpc⁻³ for late-type galaxies. The errors are estimated from Monte Carlo simulations which include the uncertainties in the Mbh--L relation, the luminosity of the host spheroid and the intrinsic scatter of the Mbh--L relation. Assuming supermassive black holes form via baryonic accretion we find that (0.008±0.002) h₇₀³ per cent of the Universe's baryons are currently locked up in supermassive black holes. This result is consistent with our previous estimate based on the Mbh--n (Sérsic index) relation.