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Suzaku Results on the Obscured Low-Luminosity Active Galactic Nucleus in NGC 4258

Makishima, Kazuo; Nakazawa, Kazuhiro; Yamada, Shin'ya +1 more

In 2006 June, the obscured low-luminosity active galactic nucleus in the nearby Seyfert 1.9 galaxy NGC 4258 was observed with Suzaku for ∼100ks. Utilizing the XIS and the HXD, the nucleus emission was detected over a ∼2 to ∼40keV range, with an unabsorbed 2-10keV luminosity of ∼8 × 10⁴⁰ergs^-1; it varied by a factor of ∼2 duri…

Broad-Band Temporal and Spectral Variation of 36 Active Galactic Nuclei Observed with Suzaku

Kunieda, Hideyo; Haba, Yoshito; Miyazawa, Takuya

36 AGN data observed by Suzaku were compiled to examine the temporal variability in different energy bands covered by soft X-ray imaging systems (XRT + XIS: 0.5-10 keV) and Hard X-ray Detector (HXD: 15-50 keV) aboard Suzaku. Three band light curves were obtained in L (0.5-2 keV), M (2-10 keV), and H (15-50 keV) with a time binning of 5760 s. The L…

Constraint of Non-Thermal X-Ray Emission from the On-Going Merger Cluster Abell 3376 with Suzaku

Isobe, Naoki; Fukazawa, Yasushi; Kokubun, Motohide +10 more

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 particles. We present early results on Suzaku observations of non-thermal emission from Abell 3376, which is a nearby on-going merger cluster. Suzaku observe…

Suzaku Observation Adjacent to the South End of the Radio Arc

Koyama, Katsuji; Tsuru, Takeshi Go; Fukuoka, Ryosuke +1 more

Suzaku observed the Galactic center region near the Radio Arc at ∼20' southeast of Sagittarius A^*. In an 18' × 18' field of view, we found four distinct X-ray sources: a bright star and a diffuse source associated with star clusters in the soft band (0.5-2.0keV), a small clump in a higher energy band (4-6keV), and a peculiar clump in th…

Spectral Variation of the Seyfert 1 Galaxy MCG -6-30-15 Observed with Suzaku

Terashima, Yuichi; Ebisawa, Ken; Inoue, Hajime +3 more

We have investigated the spectral variation of the Seyfert 1 galaxy MCG -6-30-15 observed with Suzaku in 2006 January for three separate periods spreading over fourteen days. We found that the time-averaged continuum energy spectrum between 1 keV and 40 keV can be approximated with a spectral model composed of a direct power-law component, its ref…

Suzaku Observation of the Metallicity Distribution in the Elliptical Galaxy NGC 4636

Fukazawa, Yasushi; Nishino, Sho; Hayashi, Katsuhiro +4 more

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 accurately and hence measure, for the first time, the O, Mg, Si and Fe abundances out to a radius of ~28 arcmin ($\simeq$ 140 kpc). These metal abundances a…

Suzaku and XMM-Newton Observations of Diffuse X-Ray Emission from the Eastern Tip Region of the Carina Nebula

Hamaguchi, Kenji; Corcoran, Michael F.; Petre, Robert +3 more

The eastern tip region of the Carina Nebula was observed with the Suzaku XIS for 77ks to conduct a high-precision spectral study of extended X-ray emission. XMM-Newton EPIC data of this region were also utilized to detect point sources. The XIS detected strong extended X-ray emission from the entire field-of-view with a 0.2--5keV flux of 0.7--4 × …

X-Ray Observations of the Sagittarius D HII Region toward the Galactic Center with Suzaku

Tsujimoto, Masahiro; Koyama, Katsuji; Tsuru, Takeshi Go +3 more

We present a Suzaku X-ray study of the Sagittarius D (Sgr D) HII region in the Galactic center region. Two 18' × 18' images by the X-ray Imaging Spectrometer (XIS) encompass the entire Sgr D complex. Thanks to the low background, XIS discovered two diffuse sources with low surface brightness and obtained their high signal-to-noise ratio spectra. O…

Origin of Thermal and Non-Thermal Hard X-Ray Emission from the Galactic Center

Maeda, Yoshitomo; Kokubun, Motohide; Nakazawa, Kazuhiro +10 more

We analyse new results of Chandra and Suzaku Observatories which found a flux of hard X-ray emission from the compact region around Sgr A^* (r ∼ 100 pc). We suppose that this emission is generated by accretion processes onto the central supermassive blackhole when an unbound part of captured stars obtains an additional momentum. As a res…

A New Supernova Remnant Candidate and an Associated Outflow in the Sagittarius C Region

Koyama, K.; Nobukawa, M.; Tsuru, T. G. +3 more