POLARIMETRIC STUDY OF THE IC-2944 STELLAR AGGREGATE

We present UBVRI polarimetric observations of 30 stars belonging to th e rich stellar aggregate IC 2944, which is embedded in an extensive Hn region. Within the galaxy, it is located at the inner border of the C arina spiral feature. To analyze the characteristics of the interstell ar material associated with the aggregate, we have separated the front side contribution of both color excesses and polarizations, leaving th e intra-ann values of these quantities. We have found that the foregro und polarization in the direction to IC 2944 is normal and has a lambd a(max) value of 0.550 +/- 0.025 mu. Its average direction in equatoria l coordinates is 91.2 degrees. About half of the stars not considered to be frontside have some indication of intrinsic polarization. Interp reting the polarization of the rest as intra-arm polarization, we find that Ardeberg and Maurice's Groups I, II, and III cannot be separated in terms of polarization data and that the Bright Rim Group and Group TV are significantly different from the others. Finally, stars in Gro ups I, II, III, and IV show that the intra-ann (beyond 1.4 kpc) magnet ic field is essentially contained in the plane of the sky.