Abstract
In order to tackle the problems of
low-mass end of the initial mass function (IMF) in
star-forming regions and the formation mechanisms
of brown dwarfs, we have conducted deep infrared
surveys of nearby molecular clouds. We have found
a significant population of very low-luminosity
sources with IR excesses in the Taurus cloud and
the Chamaeleon cloud core regions whose extinction
corrected J magnitudes are 3 to 8 mag fainter than
those of typical T Tauri stars in the same cloud.
Some of them are associated with even fainter
companions. Follow-up IR spectroscopy has
confirmed for the selected sources that their
photospheric temperature is around 2000 to 3000 K.
Thus, these very low-luminosity young stellar
sources are most likely very low-mass T Tauri
stars, and some of them might even be young brown
dwarfs.
The Initial Mass Function of Low‐Mass Stars and Brown Dwarfs in Young Clusters