Takashi Onaka

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The birth of very massive stars is not well understood, in contrast to the formation process of low-mass stars like our Sun. It is not even clear that massive stars can form as single entities; rather, they might form through the mergers of smaller ones born in tight groups. The recent claim of the discovery of a massive protostar in M17 (a nearby giant(More)
beta Pictoris (beta Pic) is a main-sequence star with an edge-on dust disk that might represent a state of the early Solar System. The dust does not seem to be a remnant from the original protoplanetary disk, but rather is thought to have been generated from large bodies like planetesimals and/or comets. The history and composition of the parent bodies can(More)
We have made one-dimensional raster-scan observations of the ρ Oph and σ Sco star-forming regions with two spectrometers (SWS and LWS) on board the 158 µm, and the H 2 pure rotational transition lines S(0) to S(3) are detected, and the PDR properties are derived as the radiation field scaled by the solar neighborhood value G 0 ∼ 30–500, the gas density n ∼(More)
We have collected one-dimensional raster-scan observations of the active star-forming region Sharpless 171 (S171), a typical H ii region-molecular cloud complex, with the three spectrometers (LWS, SWS, and PHT-S) on board ISO. We have detected 8 far-infrared fine-structure lines, [O iii] 52 µm, [N iii] 57 µm, [O i] 63 µm, [O iii] 88 µm, [N ii] 122 µm, [O i](More)
The Infrared Camera (IRC) is one of two focal-plane instruments on the AKARI 1 satellite. It is designed for wide-field deep imaging and low-resolution spectroscopy in the near-to mid-infrared (1.8–26.5 µm) in the pointed observation mode of AKARI. IRC is also operated in the survey mode to make an all-sky survey at 9 and 18 µm. It comprises three channels.(More)
We review the next generation Japanese infrared space mission, ASTRO-F. ASTRO-F will be the first survey of the entire sky at infrared wavelengths since the IRAS mission almost 20 years ago. ASTRO-F will survey the entire sky in 4 far-infrared bands from 50-200microns and 2 mid-infrared bands at 9 and 20microns to sensitivities of 10-1000 times deeper than(More)
which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. A 68-year-old female patient with IgG kappa-type multiple myeloma was treated with a bortezomib-based regimen. She had bilateral back pain 1 month after the chemotherapy. Because she had no skin lesions, we initially(More)
A mechanism for creating an enantioenrichment in the amino acids, the building blocks of the proteins, that involves global selection of one handedness by interactions between the amino acids and neutrinos from core-collapse supernovae is defined. The chiral selection involves the dependence of the interaction cross sections on the orientations of the spins(More)