The IMF and the brown dwarf population of the
young cluster IC 348 derived from deep near-infrared images
Thomas Preibisch & Hans Zinnecker
Poster contribution at
"The eleventh Cambridge Workshop on Cool Stars, Stellar Systems and the
Sun", Tenerife, October 1999,
to be published in the ASP Conference Series, in press, (1999)
Abstract
We have obtained and use a deep J-band image (J_lim ~ 19)
of the young cluster IC 348 to derive statistical constraints to its
stellar and sub-stellar population. Our data allow us to study the
luminosity
function of the cluster down to ~ 3 x 10^-4 L_sun,
extending well into the brown dwarf regime. We perform detailed
simulations to model the observed luminosity function and find that
the stellar part of the mass function is very well described by the
Scalo (1998) field star IMF. We can find no evidence for the existence
of a large
population of brown dwarfs in IC 348. This is in a remarkable contrast
to several other young clusters, which seem to harbour many brown
dwarfs.
We speculate that the physical environment during star formation might
be
the reason for this apparent difference in the quantity of the
sub-stellar population of young clusters.