Recently far infra-red (FIR) polarization of the 850μm continuum emission from T Tauri disks has been detected. The observed degree of polarization is around 3 %. Since thermal emission from dust grains dominates the spectral energy distribution at the FIR regime, dust grains might be the cause of the polarization. We explore alignment of dust grains by radiative torque in T Tauri disks and provide predictions for polarized emission for disks viewed at different wavelengths and viewing angles. In the presence of magnetic field, these aligned grains produce polarized emission in infrared wavelengths. When we take a Mathis-Rumpl-Nordsieck-type distribution with maximum grain size of 500-1000μm the degree of polarization is around 2-3 % level at wavelengths larger than ~100μm Our study indicates that multifrequency infrared polarimetric studies of protostellar disks can provide good insights into the details of their magnetic structure.

• JUNGYEON CHO(Dept. of Astronomy & Space Science, Chungnam National Univ.) Corresponding Author
• A. LAZARIAN(Astronomy Dept., Univ. of Wisconsin)