Evidence for a turnover in the initial mass function of low-mass stars and substellar objects: Analysis from an ensemble of young clusters

Creators: Myer, M.R.; Greissi, J.; Aversa, A.

Abstract

We present a combined analysis of the low-mass initial mass function (IMF) for seven star-forming regions. We first demonstrate that the ratios of stars to brown dwarfs are consistent with a single underlying IMF. By assuming that the underlying IMF is the same for all seven clusters and by combining the ratio of stars to brown dwarfs from each cluster, we constrain the shape of the brown dwarf IMF and find it to be consistent with a lognormal IMF. This provides the strongest constraint yet that the substellar IMF turns over (dN/dM ∝ M^-α, α<0).

Additional Information

© 2008. The American Astronomical Society. Received 2008 June 5; accepted 2008 July 1; 2008 July 29. We thank Joanna Levine, Kevin Luhman, and Cathy Slesnick for helpful discussions, as well as Neill Reid, Charles Lada, and Pavel Kroupa for comments on a draft of this Letter. The referee is acknowledged for a very fast response and for suggestions that improved the manuscript. Finally, we thank the organizers of the Cool Stars 14 Splinter Session entitled "The Formation of Low-Mass Protostars and Proto–Brown Dwarfs" for the opportunity to present a preliminary version of this work. M.R.M. gratefully acknowledges the support of a Cottrell Scholar award from the Research Corporation, NASA grant GO-9846 from the Space Telescope Science Institute, and the Arizona Space Grant Consortium.

Attached Files

Published - ANDapjl08.pdf

Files

ANDapjl08.pdf

Files (86.2 kB)

Name	Size	Download all
ANDapjl08.pdf md5:172ed9c56aefa8f743de5ca4ef30db82	86.2 kB	Preview Download

Additional details

	All versions	This version
Views	0	0
Downloads	0	0
Data volume	0 Bytes	0 Bytes