A Super Bubble Candidate in the Galactic Center and a Local Enhancement G359.77-0.09 (2009)
Mori, Hideyuki, Hyodo, Yoshiaki, Tsuru, Takeshi Go, Nobukawa, Masayoshi, Koyama, Katsuji
A 20' \times 16' elliptical ring-like structure has been found near the Galactic center in the narrow energy band corresponding to the K$\alpha$ line from He-like sulfur. In the ring, two diffuse...
An X-Ray Face-on View of the Sgr B Molecular Clouds Observed with Suzaku (2009)
Ryu, Syukyo G., Koyama, Katsuji, Nobukawa, Masayoshi, Fukuoka, Ryosuke, Tsuru, Takeshi Go
We present a new methodology to derive the positions of the Sgr B molecular clouds (MCs) along the line of sight, as an application study of the Galactic center diffuse X-rays (GCDX). The GCDX is...
A New Supernova Remnant Candidate and an Associated Outflow in the Sagittarius C Region (2009)
Tsuru, Takeshi Go, Nobukawa, Masayoshi, Nakajima, Hiroshi, Matsumoto, Hironori, Koyama, Katsuji, Yamauchi, Shigeo
We present the Suzaku results on a new candidate of a supernova remnant (SNR) in the Sagittarius C region. We detected diffuse X-rays of an elliptical shape (G359.41-0.12) and a chimney-like...
Nakajima, Hiroshi, Tsuru, Takeshi Go, Nobukawa, Masayoshi, Matsumoto, Hironori, Koyama, Katsuji, Murakami, Hiroshi, ...
This paper reports on the first results of the Suzaku observation in the Sgr C region. We detected four diffuse clumps with strong line emission at 6.4keV, Ka from neutral or low-ionized Fe. One of...
Uchiyama, Hideki, Ozawa, Midori, Matsumoto, Hironori, Tsuru, Takeshi Go, Koyama, Katsuji, Kimura, Masashi, ...
The charge transfer inefficiency (CTI) of the X-ray CCDs on board the Suzaku satellite (X-ray Imaging Spectrometers; XIS) has increased since the launch due to radiation damage, and the energy...
Ozawa, Midori, Uchiyama, Hideki, Matsumoto, Hironori, Nakajima, Hiroshi, Koyama, Katsuji, Tsuru, Takeshi Go, ...
The X-ray Imaging Spectrometer (XIS) on board the Suzaku satellite is an X-ray CCD camera system that has superior performance such as a low background, high quantum efficiency, and good energy...
Nobukawa, Masayoshi, Koyama, Katsuji, Matsumoto, Hironori, Tsuru, Takeshi Go
SAX J1748.2$-$2808 is a unique X-ray object with a flat spectrum and strong emission lines at 6.4--7.0 keV. The Suzaku satellite resolved the emission lines into 3 K-shell lines from neutral and...
X-Ray Observations of the Sagittarius D HII Region toward the Galactic Center with Suzaku (2008)
Sawada, Makoto, Tsujimoto, Masahiro, Koyama, Katsuji, Law, Casey J., Tsuru, Takeshi Go, Hyodo, Yoshiaki
We present a Suzaku X-ray study of the Sagittarius D (Sgr D) HII region in the Galactic center region. Two 18'x18' images by the X-ray Imaging Spectrometer (XIS) encompass the entire Sgr D complex....
Koyama, Katsuji, Takikawa, Yojiro, Hyodo, Yoshiaki, Inui, Tatsuya, Nobukawa, Masayoshi, Matsumoto, Hironori, ...
The high energy resolution and low background, particularly in the hard X-ray band, of the X-ray Imaging Spectrometer onboard Suzaku provide excellent spectra of the Galactic center diffuse X-rays...
Inui, Tatsuya, Koyama, Katsuji, Matsumoto, Hironori, Tsuru, Takeshi Go
We investigate long-term X-ray behaviors from the Sgr B2 complex using archival data of the X-ray satellites Suzaku, XMM-Newton, Chandra and ASCA. The observed region of the Sgr B2 complex includes...
Nobukawa, Masayoshi, Tsuru, Takeshi Go, Takikawa, Yojiro, Hyodo, Yoshiaki, Inui, Tatsuya, Nakajima, Hiroshi, ...
We made a 100 ks observation of the Sagittarius (Sgr) B1 region at (l, b) = (0.5, -0.1) near to the Galactic center (GC) with the Suzaku/XIS. Emission lines of S XV, Fe I, Fe XXV, and Fe XXVI were...
A Time-Variable X-Ray Echo: Indications of a Past Flare of the Galactic-Center Black Hole (2007)
Koyama, Katsuji, Inui, Tatsuya, Matsumoto, Hironori, Tsuru, Takeshi Go
A time-variability study of the neutral iron line flux at 6.40keV in the Sgr B2 region from data of Suzaku and Chandra is presented. The highly ionized iron line at 6.68keV is due to Galactic Center...
Development of an n-channel CCD, CCD-NeXT1, for Soft X-ray Imager onboard the NeXT satellite (2007)
Takagi, Shin-ichiro, Tsuru, Takeshi Go, Inui, Tatsuya, Matsumoto, Hironori, Koyama, Katsuji, Ozawa, Hideki, ...
NeXT (New X-ray Telescope) is the next Japanese X-ray astronomical satellite mission after the Suzaku satellite. NeXT aims to perform wide band imaging spectroscopy. Due to the successful development...
Suzaku Detection of Extended/Diffuse Hard X-Ray Emission from the Galactic Center (2007)
Yuasa, Takayuki, Tamura, Ken-ichi, Nakazawa, Kazuhiro, Kokubun, Motohide, Makishima, Kazuo, Bamba, Aya, ...
Five on-plane regions within +/- 0.8deg of the Galactic center were observed with the Hard X-ray Detector (HXD) and the X-ray Imaging Spectrometer (XIS) onboard Suzaku. From all regions, significant...
X-Ray Spectroscopy of SN 1006 with Suzaku (2007)
Yamaguchi, Hiroya, Koyama, Katsuji, Katsuda, Satoru, Nakajima, Hiroshi, Hughes, John P., Bamba, Aya, ...
We report on observations of SN 1006 with the X-ray Imaging Spectrometers (XIS) on board Suzaku. We firmly detected K-shell emission from Fe, for the first time, and find that the Fe ionization state...
The X-ray observatory Suzaku (2007)
Mitsuda, Kazuhisa, Bautz, Mark, Inoue, Hajime, Kelley, Richard L., Koyama, Katsuji, Kunieda, Hideyo, ...
Tsuru, Takeshi Go, Ozawa, Midori, Hyodo, Yoshiaki, Matsumoto, Hironori, Koyama, Katsuji, Awaki, Hisamitsu, ...
The extended X-ray emission from 'the Cap' region located 11' (11.6 kpc) above the disk of the starburst galaxy M82 has been observed with Suzaku and XMM-Newton. Owing to the good energy resolution...
Discoveries of Diffuse Iron Line Sources from the Sgr B Region (2006)
Koyama, Katsuji, Inui, Tatsuya, Hyodo, Yoshiaki, Matsumoto, Hironori, Tsuru, Takeshi Go, Maeda, Yoshitomo, ...
The radio complex Sgr B region is observed with the X-Ray Imaging Spectrometers (XIS) on board Suzaku. This region exhibits diffuse iron lines at 6.4, 6.7 and 6.9 keV, which are K$\alpha$ lines of Fe...
Iron and Nickel Line Diagnostics for the Galactic Center Diffuse Emission (2006)
Koyama, Katsuji, Hyodo, Yoshiaki, Inui, Tatsuya, Nakajima, Hiroshi, Matsumoto, Hironori, Tsuru, Takeshi Go, ...
We have observed the diffuse X-ray emission from the Galactic center (GC) using the X-ray Imaging Spectrometer (XIS) on Suzaku. The high-energy resolution and the low-background orbit provide...
Matsushita, Kyoko, Fukazawa, Yasushi, Hughes, John P., Kitaguchi, Takao, Makishima, Kazuo, Nakazawa, Kazuhiro, ...
The metallicity distribution in the Fornax cluster was studied with the XIS instrument onboard the Suzaku satellite. K-shell lines of O and Mg were resolved clearly, and the abundances of O, Mg, Si,...
Chandra Observation of the Starburst Galaxy NGC 2146 (2004)
Inui, Tatsuya, Matsumoto, Hironori, Tsuru, Takeshi Go, Koyama, Katsuji, Matsushita, Satoki, Peck, Alison B., ...
We present six monitoring observations of the starburst galaxy NGC 2146 using the Chandra X-ray Observatory. We have detected 67 point sources in the 8'.7 x 8'.7 field of view of the ACIS-S detector....
Peculiar Chemical Abundances in the Starburst Galaxy M82 and Hypernova Nucleosynthesis (2002)
Umeda, Hideyuki, Nomoto, Ken'ichi, Tsuru, Takeshi Go, Matsumoto, Hironori
X-ray observations have shown that the chemical abundance in the starburst galaxy M82 is quite rich in Si and S compared with oxygen. Such an abundance pattern cannot be explained with any...
Missing Link Found? --- The ``runaway'' path to supermassive black holes (2001)
Ebisuzaki, Toshikazu, Makino, Junichiro, Tsuru, Takeshi Go, Funato, Yoko, Zwart, Simon Portegies, Hut, Piet, ...
Observations of stellar kinematics, gas dynamics and masers around galactic nuclei have now firmly established that many galaxies host central supermassive black holes (SMBHs) with masses in the...
Matsumoto, Hironori, Tsuru, Takeshi Go, Fukazawa, Yasushi, Hattori, Makoto, Davis, David S.
We have analyzed the ASCA data of 29 nearby clusters of galaxies systematically, and obtained temperatures, iron abundances, and X-ray luminosities of their intracluster medium (ICM). We also...
Wide-Band X-Ray Spectra and Images of the Starburst Galaxy M82 (1997)
Tsuru, Takeshi Go, Awaki, Hisamitsu, Koyama, Katsuji, Ptak, Andy
The ASCA results of the starburst galaxy M82 are presented. The X-rays in the 0.5--10 keV band exhibit a thin thermal spectrum with emission lines from highly ionized magnesium, silicon, and sulfur,...
ICM masses in nearby and distant clusters of galaxies (1997)
Tsuru, Takeshi Go, Matsumoto, Hironobu, Koyama, Katsuji, Tomida, Hiroshi, Fukazawa, Yashushi, Hattori, Makoto, ...
We compile X-ray data of clusters of galaxies at a wide range of redshift $z=0.0\sim1.0$ and compare X-ray luminosities, gas masses, iron abundances and iron masses of nearby clusters and those of...