Search Publications
Metallicity of the Fossil Group NGC 1550 Observed with Suzaku
Sato, Kosuke; Nakazawa, Kazuhiro; Ohashi, Takaya +4 more
We studied the temperature and metal abundance distributions of the intra-cluster medium (ICM) in a group of galaxies, NGC 1550, observed with Suzaku. NGC 1550 is classified as a fossil group, which has few bright member galaxies, except for the central galaxy. Thus, such a type of galaxy is important to investigate how metals are enriched to the …
Subaru FOCAS Spectroscopic Observations of High-Redshift Supernovae
Wang, Lifan; Furusawa, Hisanori; Rubin, David +30 more
We present spectra of high-redshift supernovae (SNe) that were taken with the Subaru low-resolution optical spectrograph, FOCAS. These SNe were found in SN surveys with Suprime-Cam on Subaru, the CFH12k camera on the Canada-France-Hawaii Telescope, and the Advanced Camera for Surveys on the Hubble Space Telescope. These SN surveys specifically tar…
Suzaku X-Ray and Optical Spectroscopic Observations of SS 433 in the 2006 April Multiwavelength Campaign
Makishima, Kazuo; Ueda, Yoshihiro; Yamada, Shin'ya +9 more
We report on results of the 2006 April multiwavelength campaign of SS 433, focusing on X-ray data observed with Suzaku at two orbital phases (in- and out-of-eclipse phases) and on simultaneous optical spectroscopic observations. Analyzing the FeXXV Kα lines originating from the jets, we detected a rapid variability of the Doppler shifts, dz/dt ≈ 0…
X-Ray Studies of HESS J1809-193 with Suzaku
Dotani, Tadayasu; Ebisawa, Ken; Bamba, Aya +1 more
Suzaku observed the region including HESS J1809-193, a TeV unidentified source, and confirmed the existence of extended hard X-ray emission previously reported by ASCA, as well as hard X-ray emission from PSR J1809-1917 in this region. A one-dimensional profile of the diffuse emission is represented along with a Gaussian model with a best-fit σ of…
A Catalog of Suzaku/WAM Hard X-Ray Solar Flares
Yamaoka, Kazutaka; Endo, Akira; Morigami, Kouichi +10 more
We developed a catalog of solar flares in the hard X-ray band observed with the Wide-band All-sky Monitor (WAM) onboard the Suzaku satellite between 2005 July and 2009 November. During this period, 105 solar flares (GOES class X: 13, M: 29, C: 47, B: 16) were detected with WAM, including 10% of GOES-class C events reported during the same period. …
Study of the Intracluster and Intergalactic Medium in the Sculptor Supercluster with Suzaku
Kelley, Richard L.; Sato, Kosuke; Ohashi, Takaya +5 more
We studied the high-temperature plasma in the direction of the Sculptor supercluster at z = 0.108 with Suzaku. Suzaku carried out four observations in the supercluster: namely, A 2811, A 2811 offset, A 2804, A 2801 regions in 2005 November-December, including the regions beyond the virial radii of these clusters. The spectra taken in regions outsi…
Suzaku Observations of the Merging Cluster Abell 85: Temperature Map and Impact Direction
Takata, Tadafumi; Furuzawa, Akihiro; Tamura, Takayuki +2 more
To investigate the present situation of the merging in the southern outer region of Abell 85, we carried out long-time (∼100 ks) observations with Suzaku, and produced an X-ray hardness ratio map. We found a high hardness ratio peak on the east side of a subcluster located south of the cluster; an X-ray spectrum of the region including this peak i…
AKARI Infrared Observations of the Edge-On Spiral Galaxy NGC 3079
Onaka, Takashi; Yamagishi, Mitsuyoshi; Kaneda, Hidehiro +3 more
We present AKARI near- to far-infrared images of the nearby edge-on spiral galaxy NGC 3079 in 10 photometric bands. The spectral energy distribution consists of continuum emission from dust with a single temperature of 28-33 K together with strong mid-infrared emission features from polycyclic aromatic hydrocarbons (PAHs). We derived dust masses o…
On the Light-Bending Model of X-Ray Variability of MCG -6-30-15
Ebisawa, Ken; Niedźwiecki, Andrzej; Miyakawa, Takehiro +1 more
We have applied the light-bending model of X-ray variability to Suzaku data of the Seyfert 1 galaxy MCG -6-30-15. We analyzed the energy dependence of the root mean square variability, and discussed conditions necessary for the model to explain the characteristic decrease of the source variability at around 5-8 keV. A model, where the X-ray source…
Suzaku Wide-Band X-Ray Observation of the Narrow-Line Seyfert 1 Galaxy Ton S180
Hayashida, Kiyoshi; Anabuki, Naohisa; Takahashi, Hiroaki
We observed the luminous narrow-line Seyfert 1 galaxy Ton S180 with Suzaku, and obtained its wide-band (0.25-55 keV) X-ray spectra for the first time. The spectra were modeled with three components: a power-law component, a reflection from a highly ionized disk component, and an extra soft component either of a disk blackbody or a cutoff power-law…