We present a near-infrared image of UY Aur, a 0. ′′ 9 separated binary system, using the Coronagraphic Imager with Adaptive Optics on the Subaru Telescope. Thanks to adaptive optics, the spatial resolution of our image was ∼ 0. ′′ 1 in the full width at half maximum of the point spread function, the highest achieved. By comparison with previous measurements, we estimated that the orbital period is ∼ 1640 ± 90 yrs and the total mass of the binary is ∼ 1.73 ± 0.29 M ⊙. The observed H-band magnitude of the secondary varies by as much as 1.3 mag within a decade, while that of the primary is rather stable. This inconstancy may arise from photospheric variability caused by an uneven accretion rate or from the rotation of the secondary. We detected a half-ring shaped circumbinary disk around the binary with a bright southwest part but a barely detectable northeast portion. The brightness ratio is 57 ± 5. Its inner radius and inclination are about 520 AU and 42 • ± 3 • , respectively. The disk is not uniform but has remarkable features, including a clumpy structure along the disk, circumstellar material inside the inner cavity, and an extended armlike structure. The circumstellar material inside the cavity probably corresponds to a clump or material accreting from the disk onto the binary. The armlike structure is a part of the disk, created by the accretion from the outer region of the disk or encounters with other stellar systems.

A high angular resolution near-infrared image of a classical T Tauri star, DO Tau, was obtained with Coronagraphic Imager with Adaptive Optics (CIAO) mounted on the Subaru Telescope. Circumstellar emission was detected at 1: 00 7 from the central star in the direction of the redshifted jet. No emission was found toward the opposite direction. We also found one faint point source 3: 00 46 away from the central star. The following observation will reveal whether it is an associated planetary mass object or a background object.

We present an H-band image of FS Tauri, a 0. ′′ 2-separated classical T Tauri binary system, taken with the Coronagraphic Imager with Adaptive Optics (CIAO) on the Subaru Telescope. This new image, combined with Hubble Space Telescope / Advanced Camera for Surveys (HST /ACS) F606W-band polarimetric images, shows that the binary has complicated circumbinary features, including a circumbinary disk, western and eastern arm-like structures, and two cavities at the northeast and southwest. The circumbinary disk is 630 AU in radius and the southeast side of the disk is bright in the H-band. The brightness ratio (southeast/northwest) is 1.6 ± 0.4. A single Rayleigh-like scattering model indicates that the disk is inclined by 30 • to 40 • and that the southeast side corresponds to the near side along our line of sight. The H-band surface brightness of the southeast side decreases as r −1.9±0.1 from 15.2 mag arcsec −2 to 16.8 mag arcsec −2 . The outer portion of the disk is possibly more flared than its inner portion. The weak centro-symmetric polarization pattern and redder F606W−H color (4.2 ± 0.2 mag) of the southeast side are probably caused by multiple scattering events from the dust grains associated with the binary. The F606W-band image shows the bright northwest side of the disk in contrast with the H-band image. The F606W−H color of the northwest side is between 1.7 mag and 3.0 mag. We consider that Haro 6-5 B (FS Tauri B), 20 ′′ away, produces the neutral scattered light from the northwest side. This idea is supported by the polarization pattern of the northwest side, which is centro-symmetric with respect to Haro 6-5 B. The arms appear to encompass the western and eastern cavities, suggesting that the arms + cavity systems are created by a bipolar outflow from the binary. However, the direction of this outflow is inconsistent with that of outflows inferred from the 1 circumbinary disk model. These differences may arise from misalignment between the circumbinary disk and the circumstellar disks. Another mechanism forming the arms + cavity systems is considered to be the inhomogeneous density distribution of materials in the circumbinary disk.

We present H-band polarimetric imagery of UX Tau A taken with HiCIAO/AO188 on the Subaru Telescope. UX Tau A has been classified as a pre-transitional disk object, with a gap structure separating its inner and outer disks. Our imagery taken with the 0.15 ′′ (21 AU) radius coronagraphic mask has revealed a strongly polarized circumstellar disk surrounding UX Tau A which extends to 120 AU, at a spatial resolution of 0.1 ′′ (14 AU). It is inclined by 46 • ± 2 • as the west side is nearest.

We present a high-resolution ($\sim $0$.\prime\prime$1 $=$ 14 AU) $H$-band image of XZ Tau, a 0$.\prime\prime$ 3-separated classical T Tauri binary system, taken with the Coronagraphic Imager with Adaptive Optics (CIAO) on the Subaru Telescope. We found a scattered light nebula extending to $\sim $2$.\prime\prime$4 from the secondary, XZ Tau S, in the northeast region of the binary. Its surface brightness is $\sim $16.2 mag arcsec$^{-2}$ in the $H$-band, and decreases as $r^{-1.6 \pm 0.1}$. Combined with the HST/ACS polarimetric images and the [Fe ii] $\lambda$1.644 $\micron$ spectra taken with the Infrared Camera and Spectrograph (IRCS) on the Subaru Telescope, the elongated structure is identified as a wall of a cavity blown by the previously known blueshifted outflow. By a comparison with previous measurements, we estimated that the orbital period is 1010$ \pm $260 yr and the total mass of the binary is 0.62$ \pm $0.36$ M_{\odot}$. The observed $H$-band magnitudes of both the primary and the secondary varied by as much as 1 mag over this decade. These $H$-band inconstancies may arise from a variable accretion rate and changing extinction toward each component.