2007PASJ...59..487N

We have carried out the first near-infrared (NIR) polarimetric imaging observations of the central part (7'.7 x 7'.7 ∼ 110 pc x 110 pc of 30 Doradus. The totals of 106, 131, and 34 sources have significant polarization degrees at J, H, and K_s, respectively. The E-vectors toward 30 Dor were mapped with unprecedentedly high resolutions. As previously noticed by optical observations, there is an overall tendency for the E-vectors to be roughly aligned in the east-west direction. In addition, our observations reveal a more complex structure of their alignment. The position angles of the E-vectors are not uniform, but show a gradual spatial variation. It is plausible to assume that they trace the magnetic field toward 30 Dor. One of the expanding shells toward 30 Dor, Shell 5, is clearly enveloped by E-vectors. The expanding shell has probably swept the magnetic field together into the rim, while creating the curved structure. We obtained the ratios of polarization degree among the NIR wavelengths: P_H/P_J = 0.76±0.02 and P_Ks/P_H = 0.87±0.06. These fit a power-law dependence of P ∝λ^–0.9.