Search Publications
Suzaku Observations of the Cluster of Galaxies Abell 2052
Kunieda, Hideyo; Ohashi, Takaya; Mitsuda, Kazuhisa +7 more
The results from Suzaku X-ray Imaging Spectrometer (XIS) observations of relaxed cluster of galaxies, Abell 2052, are presented. Offset pointing data were used to estimate the Galactic foreground emission in the direction of the cluster. Significant soft X-ray excess emission above this foreground, the intracluster medium emission, and other backg…
Central Spiral Structure of Molecular Gas in Maffei 2
Kuno, Nario; Nakanishi, Kouichiro; Sorai, Kazuo +1 more
The distribution and kinematics of molecular gas in the central region of the barred spiral galaxy Maffei2 were investigated using a data set of 12CO(1-0),12CO(2-1), CS(2-1) lines, and 103GHz continuum. We found that the offset ridges along the kpc-scale bar continue to the central spiral structure embedded in a weak oval str…
XMM-Newton Observations of NGC 4051: Temporal Flux and Spectral Variability during Transition to the Faintest Phase in NGC 4051
Tsuruta, Sachiko; Liebmann, Andrew C.; Kunieda, Hideyo +2 more
We report on the results from temporal and spectral analyses of NGC 4051 observed with XMM-Newton. The X-ray variabilities in the higher-flux states are well explained by the combination of a variable, direct power law and a temporally stable, absorbed component. In low-flux states, however, spectral variations are mainly due to flux changes of th…
Suzaku Detection of an Intense X-Ray Flare from an A-Type Star, HD161084
Sugawara, Yasuharu; Maeda, Yoshitomo; Tsujimoto, Masahiro +4 more
We report on a serendipitous detection of an intense X-ray flare from the Tycho reference source on HD161084 during a Suzaku observation of the galactic center region for ∼20ks. The X-ray Imaging Spectrometer recorded a flare from this A1-type dwarf or subgiant star with a flux of ∼1.4 × 10-12 erg s-1 cm-2 (0.5--10…
Near-Infrared Coronagraphic Observations of a Classical TTauri Star, DO Taurus
Tamura, Motohide; Hayashi, Masahiko; Kudo, Tomoyuki +4 more
A high angular resolution near-infrared image of a classical TTauri star, DO Tau, was obtained with Coronagraphic Imager with Adaptive Optics (CIAO) mounted on the Subaru Telescope. Circumstellar emission was detected at ∼1".7 from the central star in the direction of the redshifted jet. No emission was found toward the opposite direction. We also…
Identification of the Exciting Source of CO Outflow in the Star-Formation Region GGD 12-15
Tamura, Motohide; Hashimoto, Jun; Kudo, Tomoyuki +10 more
We present results of near-infrared imaging polarimetry of the GGD 12-15 region with the IRSF 1.4m telescope and the SIRIUS camera/SIRPOL polarimeter and mid-infrared imaging with the AKARI telescope and the Infra-Red Camera (IRC). Two infrared sources, IRS9E and IRS9M near an H2O maser source situated on both sides around a VLA source …
Heavy Element Analysis of X-Ray Faint Elliptical Galaxies
Fukazawa, Yasushi; Tozuka, Miyako
Past ASCA and ROSAT observations could not support the general view that elliptical galaxies are sources of metals in the intracluster medium, since observational results have shown that X-ray faint elliptical galaxies exhibit too low metal abundances of hot interstellar medium (ISM). We investigated the radial profiles of the temperature and abun…
Vertical Temperature Structures of the Solar Corona Derived with the Hinode X-Ray Telescope
Golub, Leon; Hara, Hirohisa; Shimojo, Masumi +12 more
We obtained temperature structures in faint coronal features above and near the solar limb with the X-Ray Telescope aboard the Hinode satellite by accurately correcting the scattered X-rays from surrounding bright regions with occulted images during the solar eclipses. Our analysis yields a polar coronal hole temperature of about 1.0MK and an emis…
VERA Observations of SiO Masers in the Symbiotic Star R Aquarii
Hirota, Tomoya; Kurayama, Tomoharu; Honma, Mareki +28 more
We present phase-referenced maps of the SiO maser transitions v = 1 J = 1--0 and v = 2 J = 1--0 from the symbiotic stellar system R Aquarii, which hosts an evolved AGB star plus a hot companion. Observations were performed at two epochs: 2004.98 and 2005.98. Accurate absolute coordinates and proper motions of the emission centroid were obtained; t…
INTEGRAL and RXTE/ASM Observations on IGR J17098-3628
Zhang, Shu; Qu, Jin-Lu; Wang, Jian-Min +5 more
To further probe the possible nature of the unidentified source IGR J17098-3628, we have carried out a detailed analysis of its long-term time variability, as monitored by Rossi X-ray Timing Explorer/All Sky Monitor (RXTE/ASM), and of its hard X-ray properties, as observed by the International Gamma-Ray Astrophysics Laboratory (INTEGRAL). INTEGRAL…