Astronomy and Astrophysics – Astrophysics
Scientific paper
2003-06-25
Astron.J.126:1836,2003
Astronomy and Astrophysics
Astrophysics
To be published in AJ, October 2003. Available from ftp.lowell.edu, cd pub/dah/papers/mccl
Scientific paper
10.1086/378056
The properties of 939 star clusters in the Large and Small Magellanic Clouds were determined from ground-based CCD images in UBVR passbands. The areal coverage was extensive, corresponding to 11.0 sq-kpc in the LMC and 8.3 sq-kpc in the SMC. After corrections for reddening, the colors and magnitudes of the clusters were converted to ages and masses, and the resulting mass distributions were searched for the effects of fading, evaporation, and size-of-sample bias. The data show a clear signature of cluster fading below the detection threshold. The initial cluster mass function (ICMF) was determined by fitting the mass and age distributions with cluster population models. These models suggest a new method to determine the ICMF that is nearly independent of fading or disruption and is based on the slope of a correlation between age and the maximum cluster mass in equally spaced intervals of log-age. For a nearly uniform star formation rate, this correlation has a slope equal to 1/(alpha-1) for an ICMF of dn(M)/dM proportional to M^-alpha. We determine that alpha is between 2 and 2.4 for the LMC and SMC using this method plus another method in which models are fit to the mass distribution integrated over age and to the age distribution integrated over mass. The maximum mass method also suggests that the cluster formation rate in the LMC age gap between 3 and 13 Gy is about a factor of ten below that in the period from 0.1 Gy to 1 Gy. The oldest clusters correspond in age and mass to halo globular clusters in the Milky Way. They do not fit the trends for lower-mass clusters but appear to be a separate population that either had a very high star formation rate and became depleted by evaporation or formed with only high masses.
Dupuy Trent J.
Elmegreen Bruce G.
Hunter Deidre Ann
Mortonson Michael
No associations
LandOfFree
Cluster Mass Functions in the Large and Small Magellanic Clouds: Fading and Size of Sample Effects does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Cluster Mass Functions in the Large and Small Magellanic Clouds: Fading and Size of Sample Effects, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Cluster Mass Functions in the Large and Small Magellanic Clouds: Fading and Size of Sample Effects will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-68600