Luca Olmi

 

On the shape of the mass-functions of dense cores in the Hi-GAL SDP fields: a Bayesian approach

D. Angles, D. Elia, S. Molinari, L. Montier, M. Pestalozzi, S. Pezzuto, D. Polychroni, I. Ristorcelli, J. Rodon, M.D. Smith, L. Testi

 

The relationship between mass distributions of dense cores in star forming regions (also known as the core mass function, or CMF) and the stellar initial mass function (IMF) contains information regarding how observed samples of cores evolve into stars. The observational similarity between the CMF and the IMF has already been discussed in countless papers. The qualitative similarity between the CMF and the IMF offers support for the widely accepted idea that stars form from dense cores. Observed CMFs are typically characterized by one or more powerlaws, or sometimes by lognormal distributions.

Distinguishing between these two forms is important for our understanding of how dense molecular cores produce the full spectrum of stellar masses. However, discriminating between these two forms is complicated by the difficulty in measuring the CMF over large dynamic ranges and the fact that lognormal and powerlaw forms can look quite similar over limited mass ranges. The source catalogs extracted from the Hi-GAL science demonstration phase fields, containing thousands of sources, now offer the possibility to apply Bayesian inference techniques to compare these competing models featuring different numbers of parameters.