Tae-Soo Pyo

Thermal-infrared adaptive optics imaging- and spectro-polarimetry with the infrared camera and spectrograph (IRCS) for the Subaru Telescope

We have developed the near-infrared high-spatial resolution imaging and spectro-polarimetric modes with the laser guide adaptive optics system (AO188) and the Infrared Camera and Spectrograph (IRCS) of the 8.2-m Subaru telescope. A LiNbO3 Wollaston prism (as dual beam analyzer) and focal plane masks were installed into the camera section of the IRCS cryostat, enabling us to perform the low- and medium-resolution grism spectropolarimetry (λ/Δλ = 100-1960) as well as the imaging-polarimetry, in conjunction with a half-wave retarder, which had been introduced for the HiCIAO instrument originally, at the front of the AO188 system. The designed wavelength coverage of the Wollaston prism is 0.8-5 μm, although the polarimetry at the 0.95-2.5 μm region is presented in this paper because of the limitations on the current retarder and the dichroic beam splitter of AO188. The focal plane masks, which are reflecting mirror or slits made with tungsten carbide, provide two or four rectangular focal plane apertures with an individual field of view of 4.4 arcsec × 21 arcsec or 4.4 × 54 arcsec for the imaging-polarimetry, or two or four slits with a width of 0.10, 0.15, 0.225, and 0.60 arcsec and a length of 4.4 arcsec for the spectro-polarimetry. The Wollaston prism and polarimetry masks were installed on June and July 2013, and the polarimetric modes had the first light on October 2013. The polarization efficiency is 88-96% and 55-80% at maximum for the imaging- and spectro-polarimetry, respectively, and it depends heavily on the angle of image rotator of AO188. The measured instrumental polarization, which is introduced by the telescope tertiary mirror mainly, is 0.3-0.7%. We describe the design and current performance of the polarimetric function in the near-infrared region.

UNVEILING COMPLEX OUTFLOW STRUCTURE OF UY Aur

We present [Fe Ⅱ] ⋋ 1.257 μm spectra toward the interacting binary UY Aur with 0＂.14 angular resolution, obtained with the Near infrared Integral Field Spectrograph (NIFS) combined with the adaptive optics system Altair of the GEMINI observatory. In the [Fe Ⅱ] emission, UY Aur A (primary) is brighter than UY Aur B (secondary). The blueshifted and redshifted emission between the primary and secondary show a complicated structure. The radial velocities of the [Fe ii] emission features are similar for UY Aur A and B: ~ -100 km s -1 and ~ +130 km s -1 for the blueshifted and redshifted components, respectively. Considering the morphologies of the [Fe Ⅱ] emissions and bipolar out ow context, we concluded that UY Aur A drives fast and widely opening out ows with an opening angle of ~9° while UY Aur B has micro collimated jets.