Intrinsically polarized stars and implication for star formation in the central parsec of our galaxy

Abstract

We have carried out adaptive-optics assisted observations at the Subaru Telescope and have found 11 intrinsically polarized sources in the central parsec of our Galaxy. They are selected from 318 point sources with KS < 15.5, and their interstellar polarizations are corrected using a Stokes Q/I-U/I diagram. Considering brightness, near-infrared color excess, and the amount of intrinsic polarization, two of them are good young stellar object (YSO) candidates with an age of ∼105 yr. If they are genuine YSOs, their existence provides strong constraints on star formation mechanisms in this region. In the remaining sources, two are known as bow-shock sources in the Northern Arm. One other is also located in the Northern Arm and shows very similar properties, and thus it is likely to be a so far unknown bow-shock source. The origin of the intrinsic polarization of the other sources is as yet uncertain. © 2013. The American Astronomical Society. All rights reserved..