3 MU M Spectropolarimetry of 1120 Ice in Young Stellar Objects

Spectropolarimetry of the water-ice feature at 3.1um towards a number of YSOs is presented. The data show that excesses of polarization and changes in position angle across the feature are common. The polarization excess is due to dichroic absorption which means that the water-ice mantled grains are aligned. This may pose problems for current alignment theories. We interpret the change of position angle across the feature to mean that the magnetic field aligning the grains must be twisting along the line of sight and the ice-mantled grains must be fractionated, i.e., not evenly distributed along the line of sight.