HervéBouy

//astrophysicist

Deep wide-field surveys of young associations

I led or participated to various deep wide field surveys using the CFH12K, MegaCam and WIRCAM instruments at the CFHT. The unique sensitivity and large field-of-view of these instruments allowed us to discover a number of very faint and young brown dwarfs. Some of these objects were more than a trillion times fainter than Venus! Our studies extended previous studies beyond the planetary mass regime, confirming that objects with masses similar to Jupiter can probably form in isolation.

The distribution of mass within an association is a direct product of the fragmentation and collapse of the parent molecular cloud. As such, it is one of the most fundamental parameters of stellar formation and has been extensively studied of the past decades. While it seems clear that the mass function is universal (i.e it is similar in all associations, see Figure to the right), one important question remains... What is the lowest mass limit to the mass distribution? Objects as "light" as 5 to 10 Jupiter masses have been discovered in the early 2000. Can the fragmentation and collapse of a molecular cloud lead to the formation of even less massive objects? This is one of the questions I have been trying to answer in the context of various studies and collaborations