Suzaku Observation of the Metallicity Distribution in the Elliptical Galaxy NGC 4636 (2009)
Hayashi, Katsuhiro, Fukazawa, Yasushi, Tozuka, Miyako, Nishino, Sho, Matsushita, Kyoko, Takei, Yoh, ...
NGC 4636, an X-ray bright elliptical galaxy, was observed for 70 ks with Suzaku. The low background and good energy resolution of the XIS enable us to estimate the foreground Galactic emission...
Arai, Akira, Uemura, Makoto, Sasada, Mahito, Trushkin, Sergei A., Ueda, Yoshihiro, Takahashi, Hiromitsu, ...
We report detailed, long term near-infrared (NIR) light curves of GRS 1915+105 in 2007-2008, covering its long "soft state" for the first time. From our NIR monitoring and the X-ray data of the All...
Kawaharada, Madoka, Makishima, Kazuo, Kitaguchi, Takao, Okuyama, Sho, Nakazawa, Kazuhiro, Matsushita, Kyoko, ...
The elliptical galaxy NGC 1550 at a redshift of $z=0.01239$, identified with an extended X-ray source RX J0419+0225, was observed with {\it XMM-Newton} for 31 ks. From the X-ray data and archival...
Modeling and Reproducibility of Suzaku HXD PIN/GSO Background (2009)
Fukazawa, Yasushi, Mizuno, Tsunefumi, Watanabe, Shin, Kokubun, Motohide, Takahashi, Hiromitsu, Kawano, Naomi, ...
Suzaku Hard X-ray Detector (HXD) achieved the lowest background level than any other previously or currently operational missions sensitive in the energy range of 10--600 keV, by utilizing PIN...
Hard X-ray properties of the merging cluster Abell 3667 as observed with Suzaku (2009)
Nakazawa, Kazuhiro, Sarazin, Craig L., Kawaharada, Madoka, Kitaguchi, Takao, Okuyama, Sho, Makishima, Kazuo, ...
Ohno, Masanori, Ioka, Kunihito, Yamaoka, Kazutaka, Tashiro, Makoto, Fukazawa, Yasushi, Nakagawa, Yujin E.
We perform a time-resolved spectral analysis of bright, long Gamma-ray burst GRB 061007 using Suzaku/WAM and Swift/BAT. Thanks to the large effective area of the WAM, we can investigate the time...
Hard X-ray Properties of the Merging Cluster Abell 3667 as Observed with Suzaku (2008)
Nakazawa, Kazuhiro, Sarazin, Craig L., Kawaharada, Madoka, Kitaguchi, Takao, Okuyama, Sho, Makishima, Kazuo, ...
Wide-band Suzaku data on the merging cluster Abell 3667 were examined for hard X-ray emission in excess to the known thermal component. Suzaku detected X-ray signals in the wide energy band from 0.5...
Sasada, Mahito, Uemura, Makoto, Arai, Akira, Fukazawa, Yasushi, Kawabata, Koji S., Ohsugi, Takashi, ...
We present the result of near-infrared and optical observations of the BL Lac object S5 0716$ + $714 carried out by the KANATA telescope. S5 0716$ + $714 has both a long term high-amplitude...
The 2006 November outburst of EG Aquarii: the SU UMa nature revealed (2008)
Imada, Akira, Stubbings, Rod, Kato, Taichi, Uemura, Makoto, Krajci, Thomas, Torii, Ken'ichi, ...
We report time-resolved CCD photometry of the cataclysmic variable EG Aquarii during the 2006 November outburst During the outburst, superhumps were unambiguously detected with a mean period of...
Kawano, Naomi, Fukazawa, Yasushi, Nishino, Sho, Nakazawa, Kazuhiro, Kitaguchi, Takao, Makishima, Kazuo, ...
Clusters of galaxies are among the best candidates for particle acceleration sources in the universe, a signature of which is non-thermal hard X-ray emission from the accelerated relativistic...
Ohno, Masanori, Fukazawa, Yasushi, Takahashi, Takuya, Yamaoka, Kazutaka, Sugita, Satoshi, Pal'shin, Valentin, ...
We have performed a joint analysis of prompt emission from four bright short gamma-ray bursts (GRBs) with the Suzaku-WAM and the Konus-Wind experiments. This joint analysis allows us to investigate...
ASCA OBSERVATIONS OF THE SPECTRUMOF THE X-RAY BACKGROUND (2007)
Keith C. Gendreau, Richard Mushotzky, Andrew C. Fabian, Tsuneo Kii, Stephen S. Holt, Peter J. Serlemitsos, ...
We present initial results from ASCA on the spectrum of the Cosmic X-ray Background from 0.4 to 10 keV. About 250 ksec of deep survey data has been collected from the performance verification phase...
In Orbit Timing Calibration of the Hard X-Ray Detector on Board Suzaku (2007)
Terada, Yukikatsu, Enoto, Teruaki, Miyawaki, Ryouhei, Ishisaki, Yoshitaka, Dotani, Tadayasu, Ebisawa, Ken, ...
The hard X-ray detector (HXD) on board the X-ray satellite Suzaku is designed to have a good timing capability with a 61 $\mu$s time resolution. In addition to detailed descriptions of the HXD timing...
Tokoi, Kazuyo, Sato, Kosuke, Ishisaki, Yoshitaka, Ohashi, Takaya, Yamasaki, Noriko Y., Nakazawa, Kazuhiro, ...
We present results of 120 ks observation of a compact group of galaxies HCG~62 ($z=0.0145$) with Suzaku XIS and HXD-PIN\@. The XIS spectra for four annular regions were fitted with two temperature...
PoGOLite - A High Sensitivity Balloon-Borne Soft Gamma-ray Polarimeter (2007)
Kamae, Tuneyoshi, Andersson, Viktor, Arimoto, Makoto, Axelsson, Magnus, Bettolo, Cecilia Marini, Björnsson, Claes-Ingvar, ...
We describe a new balloon-borne instrument (PoGOLite) capable of detecting 10% polarisation from 200mCrab point-like sources between 25 and 80keV in one 6 hour flight. Polarisation measurements in...
Suzaku wide-band observations of SN 1006 (2007)
Bamba, Aya, Fukazawa, Yasushi, Hiraga, Junko S., Hughes, John P., Katagiri, Hideaki, Kokubun, Motohide, ...
We report on the wide band spectra of SN 1006 as observed by Suzaku. Thermal and nonthermal emission are successfully resolved thanks to the excellent spectral response of Suzaku's X-ray CCD XIS. The...
Low/Hard State Spectra of GRO J1655-40 Observed with Suzaku (2007)
Takahashi, Hiromitsu, Fukazawa, Yasushi, Mizuno, Tsunefumi, Hirasawa, Ayumi, Kitamoto, Shunji, Sudoh, Keisuke, ...
The Galactic black-hole binary GRO J1655$-$40 was observed with Suzaku on 2005 September 22--23, for a net exposure of 35 ks with the X-ray Imaging Spectrometer (XIS) and 20 ks with the Hard X-ray...
Sato, Kosuke, Yamasaki, Noriko Y., Ishida, Manabu, Ishisaki, Yoshitaka, Ohashi, Takaya, Kawahara, Hajime, ...
We carried out observations of the central and 20' east offset regions of the cluster of galaxies Abell 1060 with Suzaku. Spatially resolved X-ray spectral analysis has revealed temperature and...
Miniutti, Giovanni, Fabian, Andrew C., Anabuki, Naohisa, Crummy, Jamie, Fukazawa, Yasushi, Gallo, Luigi, ...
Revealing the high energy emission from the obscured Seyfert galaxy MCG−5–23–16 with Suzaku (2007)
Reeves, James N., Awaki, Hisamitsu, Dewangan, Gulab C., Fabian, Andy C., Fukazawa, Yasushi, Gallo, Luigi, ...
The X-ray observatory Suzaku (2007)
Mitsuda, Kazuhisa, Bautz, Mark, Inoue, Hajime, Kelley, Richard L., Koyama, Katsuji, Kunieda, Hideyo, ...
Hard X-ray investigation of the galactic center region with Suzaku (2007)
Kokubun, Motohide, Yuasa, Takayuki, Tamura, Ken-ichi, Makishima, Kazuo, Takahashi, Tadayuki, Nakazawa, Kazuhiro, ...
The long Suzaku observation of MCG-6-30-15 (2007)
Miniutti, Giovanni, Fabian, Andrew C., Crummy, Jamie, Larsson, Josefin, Anabuki, Naohisa, Fukazawa, Yasushi, ...
Hard X-Ray Properties of Groups of Galaxies as Observed with ASCA (2006)
Nakazawa, Kazuhiro, Makishima, Kazuo, Fukazawa, Yasushi
X-ray spectra of groups of galaxies, obtained with the GIS instrument onboard ASCA, were investigated for diffuse hard X-rays in excess of the soft thermal emission from their inter-galactic medium...
Kubota, Aya, Dotani, Tadayasu, Cottam, Jean, Kotani, Taro, Done, Chris, Ueda, Yoshihiro, ...
We present the results of six Suzaku observations of the recurrent black hole transient 4U1630-472 during its decline from outburst from February 8 to March 23 in 2006. All observations show the...
Revealing the High Energy Emission from the Obscured Seyfert Galaxy MCG -5-23-16 with Suzaku (2006)
Reeves, James N., Awaki, Hisamitsu, Dewangan, Gulab C., Fabian, Andy C., Fukazawa, Yasushi, Gallo, Luigi, ...
We report on a 100 ks Suzaku observation of the bright, nearby (z=0.008486) Seyfert 1.9 galaxy MCG -5-23-16. The broad-band (0.4-100 keV) X-ray spectrum allows us to determine the nature of the high...
Spectropolarimetric Study on Circumstellar Structure of Microquasar LS I +61deg 303 (2006)
Nagae, Osamu, Kawabata, Koji S., Fukazawa, Yasushi, Yamashita, Takuya, Ohsugi, Takashi, Uemura, Makoto, ...
We present optical linear spectropolarimetry of the microquasar LS I +61$^{\circ}$ 303. The continuum emission is mildly polarized (up to 1.3 %) and shows almost no temporal change. We find a...
Ota, Naomi, Fukazawa, Yasushi, Fabian, Andrew C., Kanemaru, Takehiro, Kawaharada, Madoka, Kawano, Naomi, ...
The Centaurus cluster (z=0.0104) was observed with the X-ray Imaging Spectrometer (XIS) onboard the Suzaku X-ray satellite in three pointings, one centered on the cluster core and the other two...
Miniutti, Giovanni, Fabian, Andrew C., Anabuki, Naohisa, Crummy, Jamie, Fukazawa, Yasushi, Gallo, Luigi, ...
Suzaku has, for the first time, enabled the hard X-ray variability of the Seyfert 1 galaxy MCG-6-30-15 to be measured. The variability in the 14-45 keV band, which is dominated by a strong reflection...
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 and XMM-Newton Observations of a Group of Galaxies HCG 62 (2006)
Morita, Umeyo, Ishisaki, Yoshitaka, Yamasaki, Noriko Y., Ota, Naomi, Kawano, Naomi, Fukazawa, Yasushi, ...
We present results from Chandra and XMM-Newton observations of the bright group of galaxies HCG 62. There are two cavities at about 30'' northeast and 20'' southwest of the central galaxy in the...
Three Spectral States of the Disk X-Ray Emission of the Black-Hole Candidate 4U 1630-47 (2005)
Abe, Yukiko, Fukazawa, Yasushi, Kubota, Aya, Kasama, Daisuke, Makishima, Kazuo
We studied a time history of X-ray spectral states of a black-hole candidate, 4U 1630-47, utilizing data from a number of monitoring observations with the Rossi X-Ray Timing Explorer over 1996--2004....
Results of a Si/CdTe Compton Telescope (2005)
Oonuki, Kousuke, Tanaka, Takaaki, Watanabe, Shin, Takeda, Shin'ichiro, Nakazawa, Kazuhiro, Mitani, Takefumi, ...
We have been developing a semiconductor Compton telescope to explore the universe in the energy band from several tens of keV to a few MeV. We use a Si strip and CdTe pixel detector for the Compton...
Fukazawa, Yasushi, Makishima, Kazuo, Ohashi, Takaya
Utilizing ASCA archival data of about 300 objects of elliptical galaxies, groups, and clusters of galaxies, we performed systematic measurements of the X-ray properties of hot gas in their systems,...
A Prototype Si/CdTe Compton Camera and the Polarization Measurement (2004)
Mitani, Takefumi, Tanaka, Takaaki, Nakazawa, Kazuhiro, Takahashi, Tadayuki, Takashima, Takeshi, Tajima, Hiroyasu, ...
A Compton camera is the most promising approach for gamma-ray detection in the energy region from several hundred keV to MeV, especially for application in high energy astrophysics. In order to...
Development of a Si/CdTe semiconductor Compton telescope (2004)
Tanaka, Takaaki, Mitani, Takefumi, Watanabe, Shin, Nakazawa, Kazuhiro, Oonuki, Kousuke, Sato, Goro, ...
We are developing a Compton telescope based on high resolution Si and CdTe imaging devices in order to obtain a high sensitivity astrophysical observation in sub-MeV gamma-ray region. In this paper,...
Gamma-ray Polarimetry with Compton Telescope (2004)
Tajima, Hiroyasu, Madejski, Grzegorz, Mitani, Takefumi, Tanaka, Takaaki, Nakamura, Hidehito, Nakazawa, Kazuhiro, ...
Compton telescope is a promising technology to achieve very high sensitivity in the soft gamma-ray band (0.1-10 MeV) by utilizing Compton kinematics. Compton kinematics also enables polarization...
Reflection Component in the Hard X-Ray Emission from the Seyfert 2 Galaxy Mrk 1210 (2004)
Ohno, Masanori, Fukazawa, Yasushi, Iyomoto, Naoko
The Seyfert 2 galaxy Mrk 1210 was found to exhibit a flat hard X-ray component by ASCA, although ASCA could not distinguish whether it is an absorbed direct component or a reflected one. We then...
Chandra X-Ray Spectral Analysis of Cooling Flow Clusters, 2A 0335+096 and Abell 2199 (2003)
Kawano, Naomi, Ohto, Akimitsu, Fukazawa, Yasushi
We report on a spatially resolved analysis of Chandra X-ray data on a nearby typical cooling flow cluster of galaxies 2A 0335+096, together with A 2199 for a comparison. As recently found in the...
A new candidate for the dark group of galaxies, RX J0419+0225 (2003)
Kawaharada, Madoka, Makishima, Kazuo, Takahashi, Isao, Nakazawa, Kazuhiro, Matsushita, Kyoko, Shimasaku, Kazuhiro, ...
Extended Thermal X-ray Emission from the Spiral-Dominant Group of Galaxies HCG 57 (2002)
Fukazawa, Yasushi, Kawano, Naomi, Ohto, Akimitsu
We observed a group of galaxies, HCG 57, with ASCA. Regardless that their member galaxies are dominated by spiral galaxies, we detected extended thermal X-ray emission that is attributed to hot gas...
Search for Hot Gas in the Local Group with ASCA (2002)
Osone, Satoko, Makishima, Kazuo, Matsuzaki, Keiichi, Ishisaki, Yoshitaka, Fukazawa, Yasushi
An X-ray study was made to examine whether some part of the soft X-ray background is coming from hot gas in the Local Group. For this purpose, four consecutive pointings were made with ASCA toward a...
BeppoSAX Observation of the NGC 3079 Nucleus (2001)
Iyomoto, Naoko, Fukazawa, Yasushi, Nakai, Naomasa, Ishihara, Yuko
Using the BeppoSAX observatory, we have observed a nearby LINER/Seyfert 2 galaxy, NGC 3079, which is known as an outflow galaxy and a bright H_2O-maser source. Using the PDS detector, we have...
Fukazawa, Yasushi, Iyomoto, Naoko, Kubota, Aya, Matsumoto, Yukari, Makishima, Kazuo
We observed the nearby galaxy M~51 (NGC 5194) with BeppoSAX. The X-ray properties of the nucleus below 10 keV are almost the same as the ASCA results regarding the hard component and the neutral Fe...
X-Ray Probing of the Central Regions of Clusters of Galaxies (2001)
Makishima, Kazuo, Ezawa, Hajime, Fukazawa, Yasushi, Honda, Hirohiko, Ikebe, Yasushi, Kamae, Tuneyoshi, ...
Results of ASCA X-ray study of central regions of medium-richness clusters of galaxies are summarized, emphasizing differences between cD and non-cD clusters. The intra-cluster medium (ICM) is likely...
Detection of Excess Hard X-ray Emission from the Group of Galaxies HCG62 (2000)
Fukazawa, Yasushi, Nakazawa, Kazuhiro, Isobe, Naoki, Makishima, Kazuo, Matsushita, Kyoko, Ohashi, Takaya, ...
From the group of galaxies HCG62, we detected an excess hard X-ray emission in energies above $\sim 4$ keV with \A SCA. The excess emission is spatially extended up to $\sim10'$ from the group...
Discovery of Spectral Transitions from Two Ultra-Luminous Compact X-Ray Sources in Ic342 (2000)
Kubota, Aya, Mizuno, Tsunefumi, Makishima, Kazuo, Fukazawa, Yasushi, Kotoku, Jun'ichi, Ohnishi, Tomohisa, ...
Two {\it ASCA} observations were made of two ultra-luminous compact X-ray sources (ULXs), Source 1 and Source 2, in the spiral galaxy IC 342. In the 1993 observation, Source 2 showed a 0.5--10 keV...
ASCA Observations of Three Shakhbazyan's Compact Groups of Galaxies (2000)
Takahashi, Isao, Fukazawa, Yasushi, Kodaira, Keiichi, Makishima, Kazuo, Nakazawa, Kazuhiro, Xu, Haiguang
X-ray observations of three Shakhbazyan's Compact Groups of Galaxies, SCGG 202, SCGG 205, and SCGG 223, are presented for the first time. Extended X-ray emission was detected from SCGG 202 and SCGG...
Tamura, Takayuki, Makishima, Kazuo, Fukazawa, Yasushi, Ikebe, Yasushi, Xu, Haiguang
X-ray spectral and imaging data from ASCA and ROSAT were used to measure the total mass profile in the central region of Abell 1060, a nearby and relatively poor cluster of galaxies. The ASCA X-ray...
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...
Two-Phased Intra-Cluster Medium in the Centaurus Cluster of Galaxies (1999)
Ikebe, Yasushi, Makishima, Kazuo, Fukazawa, Yasushi, Tamura, Takayuki, Xu, Haiguang, Ohashi, Takaya, ...
ASCA and ROSAT data of the Centaurus cluster were analyzed. A central excess in the radial brightness profile is found in the hard energy band up to 10keV. This requires a deeper central potential...
Mass and Metallicity of Five X-ray Bright Galaxy Groups (1998)
Hwang, Una, Mushotzky, Richard F., Burns, Jack O., Fukazawa, Yasushi, White, Richard A., ...
We present ASCA X-ray observations of a sample of five groups selected from a cross-correlation of the ROSAT All-Sky Survey with the White et al. optical catalog of groups. These X-ray bright groups...
Low-luminosity X-ray Active Nuclei in S0 galaxies NGC 3065 and NGC 4203 (1998)
Iyomoto, Naoko, Makishima, Kazuo, Matsushita, Kyoko, Fukazawa, Yasushi, Tashiro, Makoto, Ohashi, Takaya
We present ASCA X-ray results on two S0 galaxies, NGC 3065 and NGC 4203. In both galaxies, we detected hard X-ray emission from a point-like source at the nucleus. Single power law model having a...
ASCA Measurements of Silicon and Iron Abundances in the Intracluster Medium (1998)
Fukazawa, Yasushi, Makishima, Kazuo, Tamura, Takayuki, Ezawa, Hajime, Xu, Haiguang, Ikebe, Yasushi, ...
We analyzed the ASCA X-ray data of 40 nearby clusters of galaxies, whose intracluster-medium temperature distributes in the range of 0.9--10 keV. We measured the Si and Fe abundances of the...
"October 1998."
ASCA Observations of the Spectrum of the X-ray Background (1995)
Keith Gendreau, Richard Mushotzky, Andrew C. Fabian, Stephen S. Holt, Peter J. Serlemitsos, Yasushi Fukazawa, ...
We present initial results from ASCA on the spectrum of the Cosmic X-ray Background from 0.4 to 10 keV. About 250 ksec of deep survey data has been collected from the performance verification phase...