| Full text | |
| Author(s): |
Munyaneza‚ F.
;
Biermann‚ P.L.
Total Authors: 2
|
| Document type: | Journal article |
| Source: | Astronomy & Astrophysics; v. 436, n. 3, p. 805-815, 2005. |
| Abstract | |
We report on a calculation of the growth of the mass of supermassive black holes at galactic centers from dark matter and Eddington - limited baryonic accretion. Assuming that dark matter halos are made of fermions and harbor compact degenerate Fermi balls of masses from 10(3) M-circle dot to 10(6) M-circle dot, we find that dark matter accretion can boost the mass of seed black holes from about similar to 5 M-circle dot to 10(3-4) M-circle dot black holes, which then grow by Eddington-limited baryonic accretion to supermassive black holes of 10(6-9) M-circle dot. We then show that the formation of the recently detected supermassive black hole of 3 x 10(9) M-circle dot at a redshift of z = 6.41 in the quasar SDSS J114816.64+525150.3 could be understood if the black hole completely consumes the degenerate Fermi ball and then grows by Eddington-limited baryonic accretion. In the context of this model we constrain the dark matter particle masses to be within the range from 12 keV/c(2) to about 450 keV/c(2). Finally we investigate the black hole growth dependence on the formation time and on the mass of the seed black hole. We find that in order to fit the observed data point of M-BH similar to 3 x 10(9) M-circle dot and z similar to 6.41, dark matter accretion cannot start later than about 2 x 10(8) years and the seed BH cannot be greater than about 10(4) M-circle dot. Our results are in full agreement with the WMAP observations that indicate that the first onset of star formation might have occurred at a redshift of z similar to 15-20. For other models of dark matter particle masses, corresponding constraints may be derived from the growth of black holes in the center of galaxies. (AU) | |
| FAPESP's process: | 00/06695-0 - Galaxy Evolution and Activity |
| Grantee: | Ronaldo Eustaquio de Souza |
| Support Opportunities: | Research Projects - Thematic Grants |