Abstract.
There are evidences that the small compact clouds (also known as Bok
Globules) are undergoing gravitational collapse and some of them may
form low mass stars. But as these clouds undergo gravitational
collapse, the ambient magnetic field plays a key role in the
collapse dynamics. The strength and geometry of the magnetic field
are normally estimated through the polarimetry of stars background
to the cloud. The optical polarization is caused by selective
absorption of background starlight by the magnetically aligned dust
(grain) present in the cloud. When observed in NIR (and sub-mm),
the same grains are seen in thermal re-emission. In order to study
the role of grains and magnetic field, often extinction measurements
are also made in such clouds. With these aims, recently such clouds
have been studied in photometry, polarimetry and spectroscopy. These
results are discussed with possible interpretations.
Key words:stars: formation -- ISM: dust -- extinction