Published in "Observational Evidence for the Black Holes in the Universe", Conference held in Calcutta, January 11-17th, 1999., p. 157

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Abstract. I review the status of observational determinations of central masses in nearby galactic nuclei. Results from a variety of techniques are summarized, including ground-based and space-based optical spectroscopy, radio VLBI measurements of luminous water vapor masers, and variability monitoring studies of active galactic nuclei. I will also discuss recent X-ray observations that indicate relativistic motions arising from the accretion disks of active nuclei. The existing evidence suggests that supermassive black holes are an integral component of galactic structure, at least in elliptical and bulge-dominated galaxies. The black hole mass appears to be correlated with the mass of the spheroidal component of the host galaxy. This finding may have important implications for many astrophysical issues.

Table of Contents

MOTIVATION

EARLY CLUES FROM PHOTOMETRY

METHODS BASED ON STELLAR KINEMATICS

METHODS BASED ON GAS KINEMATICS

Optical Emission Lines

Radio Spectroscopy of Water Masers

Determining Central Masses of Active Galactic Nuclei

INDIRECT, BUT TANTALIZING EVIDENCE

ARE THE MASSIVE DARK OBJECTS REALLY BLACK HOLES?

THE BLACK-HOLE MASS/BULGE MASS RELATION

ARE SUPERMASSIVE BLACK HOLES UBIQUITOUS?

SOME IMPLICATIONS AND FUTURE DIRECTIONS

REFERENCES

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