Nobuhiko Kusakabe

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On the basis of the near infrared observations of bulge red clump stars near the Galactic center, we have determined the galactocentric distance to be R0 = 7.52± 0.10 (stat) ±0.35 (sys) kpc. We observed the red clump stars at | l |. 1. 0 and 0. 7 .| b |. 1. 0 with the IRSF 1.4 m telescope and the SIRIUS camera in the H and KS bands. After extinction and(More)
We present a wide-field (∼6′ × 6′) and deep near-infrared (K s band: 2.14 μm) circular polarization image in the Orion nebula, where massive stars and many low-mass stars are forming. Our results reveal that a high circular polarization region is spatially extended (∼0.4 pc) around the massive star-forming region, the BN/KL nebula. However, other regions,(More)
The search for habitable exoplanets in the Universe is actively ongoing in the field of astronomy. The biggest future milestone is to determine whether life exists on such habitable exoplanets. In that context, oxygen in the atmosphere has been considered strong evidence for the presence of photosynthetic organisms. In this paper, we show that a previously(More)
A high angular resolution near-infrared polarized-intensity image of the GG Tau A binary system was obtained with the Subaru Telescope. The image shows the circumbinary disk scattering the light from the central binary. The azimuthal profile of the polarized intensity of the circumbinary disk is roughly reproduced by a simple disk model with the(More)
We have conducted a systematic near-infrared circular polarization (CP) survey in star-forming regions, covering high-mass, intermediate-mass, and low-mass young stellar objects. All the observations were made using the SIRPOL imaging polarimeter on the Infrared Survey Facility 1.4 m telescope at the South African Astronomical Observatory. We present the(More)
Using the ASTE 10 m submillimeter telescope and the 1.4 m Infrared Survey Facility (IRSF), we performed an extensive outflow survey in the Orion Molecular Cloud -2 and -3 region. Our survey, which includes 41 potential star-forming sites, has been newly compiled using multi-wavelength data based on millimeterand submillimeter-continuum observations as well(More)
HiCIAO is a high contrast instrument which works with a 188 element adaptive optics system (AO188) for the Subaru Telescope. The instrument is specifically designed for extrasolar planet search and studies of protoplanetary or debris disks. A coronagraph technique and some differential observing modes implemented in HiCIAO extract faint objects from the sea(More)
We present a polarimetric map of a 20′×20′ area toward the Galactic center. The polarization of point sources has been measured in the J , H , and KS bands using the near-infrared polarimetric camera SIRPOL on the 1.4 m telescope IRSF. One percent or better accuracy of polarization degree is achieved for sources with J < 14.5, H < 13.5, and KS < 12.0.(More)
We have determined the ratios of total to selective extinction in the nearinfrared bands (J,H,KS) toward the Galactic center from the observations of the region | l |. 2. 0 and 0. 5 .| b |. 1. 0 with the IRSF telescope and the SIRIUS camera. Using the positions of red clump stars in color-magnitude diagrams as a tracer of the extinction and reddening, we(More)
We have conducted deep JHKs imaging polarimetry of a ∼8 × 8 area of the NGC 2071 star forming region. Our polarization data have revealed various infrared reflection nebulae (IRNe) associated with the central IR young star cluster NGC2071IR and identified their illuminating sources. There are at least 4 IRNe in NGC2071IR and several additional IRNe are(More)