Poster abstract

Binary formation mechanisms. Constraints from the Companion Mass Ratio
Maddalena Reggiani & Michael R. Meyer

Abstract

We present a statistical comparison of the mass ratio distribution of
companions, as observed in different multiplicity surveys, to a recent
estimate of the single object mass function (Chabrier2005). The main goal
of our analysis is to test whether or not the observed companion mass ratio
distribution (CMRD) as a function of primary star mass and star formation
environment is consistent with having been drawn from the field star IMF.
We consider samples of companions for M dwarfs, G and OB stars, found in
the field, open clusters, and star-forming regions, and we compare them
with populations of binaries generated through Monte Carlo simulations by
random pairing from the assumed IMF for a fixed primary mass.
The analysis of connections between the CMRD and the IMF over a broad
range of primary masses and variety of environments can help in
discriminating different binary formation mechanisms and investigating
about the origin of the field.