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G. A. Shields, K. Gebhardt, S. Salviander, B. J. Wills, M. Yuan (U. Texas), B. Xie (Rutgers U.), M. Dietrich (U. Florida)
Supermassive black holes in galactic nuclei have masses closely related to the properties of the host galaxy bulge. In particular, MBH varies as the fourth power of \sigma, the stellar velocity dispersion (Tremaine et al. 2002, ApJ in press, and references therein). The origin of the black hole-bulge relation is unknown, although theoretical suggestions abound. An important clue would be provided by knowledge of how the relation has evolved over cosmic time. This requires measurement of black hole masses and galactic potentials at large look-back times, which is difficult to do directly. However, black hole masses may be derived from the continuum luminosity and the widths of the broad Balmer lines of QSOs (e.g., Kaspi et al. 2000, ApJ 533, 631), and \sigma may be derived from the widths of the narrow [O III] lines (Nelson 2000, ApJ, 544, L91). We have carried out this program for a set of published and unpublished observations of Seyfert galaxies and QSOs. Results for low redshift objects support the use of this method to derive MBH and \sigma. The few available measurements of high redshift QSOs are consistent little or no change in the MBH-\sigma relation between the present and redshifts up to z = 3.3, when the universe was only two billion years old.
This material is based in part upon work supported by the Texas Advanced Research Program under Grant No. 003658-0177-2001.
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Bulletin of the American Astronomical Society, 34
© 2002. The American Astronomical Soceity.