17:15 〜 18:30
[MIS02-P03] Circular polarization induced by aligned dust grains at UV wavelength
キーワード：円偏光、非球形ダスト、鏡像体過剰
The L-acid excesses have been discovered in meteorites, and it is the candidate of the origin of the bimolecular chirality. Circular polarization (CP) at the ultraviolet (UV) wavelength causes the enantiomeric excesses of amino acids. In the interstellar medium, UV photons are mainly emitted from massive stars. The star-forming regions around them are the production sites of the enantiomeric excesses if CP light at the UV wavelength exists. In observations, the high CP degree (>20%) at the near-infrared (NIR) wavelength is discovered, and it is caused by the light scattering on the aligned dust grains. However, it is unclear that UV light has a high CP degree. In this study, we develop the radiative transfer code with the Monte Carlo technic, including the Stokes parameters (Fukushima et al. 2020). We consider the light scattering in the dusty slab around a massive star. We find that the high degree of CP (>20%) is realized at UV wavelength with the dust size model of the MRN mixture. On the other hand, the high CP degree at the NIR wavelength is only realized if the micron-size dust grain is contained. In the case of the standard MRN mixture, the CP degree is less than 10%, and the observed high CP degree is not caused. We conclude that the high CP degree at UV wavelength is easily induced compared with that of the NIR wavelength.