Luminosity function and mass segregation in M92
G. Andreuzzi 1,
R. Buonanno 1,
F. Fusi Pecci 2,
G. Iannicola 1 and
G. Marconi 1
Received 26 May 1999 / Accepted 27 October 1999
We present WFPC2-HST observations of the lower main sequence of the galactic globular cluster M92 (NGC6341), extending down to V 27. Our data, which cover a region of the cluster extending from the very center out to r 380 arcsec, show that the slope of the luminosity function becomes flatter going towards the center of the cluster, as expected if M92 is a dynamically relaxed system.
The slope of the inferred power-law mass function we computed ranges from x 0.7 for the field centered at r = 18.61 core radii, to x 0.3 for the annular field centered at r = 10.61 core radii, where a value of 14 arcsec has been used for the core radius of M92. Such a result, obtained without making any use of dynamical theoretical models, shows that segregation effects are at work in M92.
Key words: Galaxy: globular clusters: individual: M92 stars: low-mass, brown dwarfs stars: luminosity function, mass function
Send offprint requests to: G. Andreuzzi
© European Southern Observatory (ESO) 2000
Online publication: January 18, 2000