Magnetic field structure in the vicinity of five dark cloud complexes

The magnetic-field geometry in the outer regions of five dark cloud complexes has been mapped by measuring the linear polarization of stars background to the cloud peripheries. These observations are aimed at establishing a relationship between field geometry and cloud morphology for cloud complexes which are active sites of star formation. For one of these complexes, Barnard 42, polarization measurements were also obtained (at a wavelength of 2.2 microns) for several heavily obscured stars in order to probe the magnetic-field geometry and grain-alignment efficiency in the dense central regions of this dark cloud.