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No supermassive black hole in M33?
D Merritt1, L Ferrarese, C L Joseph
1Department of Physics and Astronomy, Rutgers University, New Brunswick, NJ 08854, USA. merritt@physics.rutgers.edu
Science (New York, N.Y.)
|July 21, 2001
Summary
Astronomers used the Space Telescope Imaging Spectrograph to observe M33
Area of Science:
- * Astrophysics and cosmology
- * Galactic nuclei and supermassive black holes
Background:
- * M33 is the third-brightest galaxy in the Local Group.
- * Supermassive black holes are expected to have a steep rise in stellar velocities within their gravitational influence radius.
- * Previous observations lacked the resolution to study M33's nucleus in detail.
Purpose of the Study:
- * To achieve unprecedented resolution of M33's galactic nucleus.
- * To investigate the stellar velocity profile near the galactic center.
- * To constrain the mass of a potential central black hole in M33.
Main Methods:
- * Utilized the Space Telescope Imaging Spectrograph (STIS) for high-resolution observation.
- * Analyzed stellar velocities within one parsec of M33's center.
- * Compared observed velocities to models of supermassive black hole influence.
Main Results:
- * Observed a decrease in random stellar velocities within one parsec of M33's center.
- * Implied an upper limit of only 3000 solar masses for the central black hole.
- * This mass is significantly lower (three orders of magnitude) than other known supermassive black holes.
Conclusions:
- * The findings challenge the typical supermassive black hole model in galactic nuclei.
- * The low inferred black hole mass in M33 suggests unique formation or evolutionary pathways.
- * Further research is needed to understand the relationship between such low-mass black holes and their host galaxies.
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