Search Publications
Suzaku Detection of Extended/Diffuse Hard X-Ray Emission from the Galactic Center
Maeda, Yoshitomo; Kokubun, Motohide; Makishima, Kazuo +12 more
Five on-plane regions within ±0°.8 of the galactic center were observed with the Hard X-ray Detector (HXD) and the X-ray Imaging Spectrometer (XIS) aboard Suzaku. From all regions, significant hard X-ray emission was detected with HXD-PIN up to 40keV, in addition to the extended plasma emission which is dominant in the XIS band. The hard X-ray sig…
Suzaku Observation of the Metallicity in the Hot Interstellar Medium of the Isolated Elliptical Galaxy NGC 720
Fukazawa, Yasushi; Anabuki, Naohisa; Matsushita, Kyoko +3 more
The metal abundances in the interstellar medium of the isolated elliptical galaxy NGC 720 were studied with the CCD X-ray Imaging Spectrometer (XIS) aboard the Suzaku satellite. The high detection efficiency along with the excellent spectral resolution of the XIS allowed the K-shell lines of O and Mg to be clearly resolved, and the abundances of O…
Suzaku X-Ray Spectroscopy of a Peculiar Hot Star in the Galactic Center Region
Nagata, Tetsuya; Tsujimoto, Masahiro; Koyama, Katsuji +5 more
We present the results of a Suzaku study of a bright point-like source in the 6.7keV intensity map of the Galactic center region. We detected an intense FeXXV 6.7keV line with an equivalent width of ∼1keV as well as emission lines of highly ionized Ar and Ca from a spectrum obtained by the X-ray Imaging Spectrometer. The overall spectrum is descri…
Performance of an Imaging Fourier Transform Spectrometer with Photoconductive Detector Arrays: An Application for the AKARI Far-Infrared Instrument
Nakagawa, Takao; Shirahata, Mai; Doi, Yasuo +10 more
We have developed an imaging Fourier transform spectrometer (FTS) for space-based far-infrared astronomical observations. The FTS employs newly developed photoconductive detector arrays with acapacitive trans-impedance amplifier, which makes the FTS acompletely unique instrument. The FTS was installed as afunction of the far-infrared instrument (F…
Galaxy Clusters at 0.9 < z < 1.7 in the AKARI NEP Deep Field
Goto, Tomotsugu; Inami, Hanae; Nakagawa, Takao +11 more
There is ahuge gap between the properties of red-sequence selected massive galaxy clusters at z < 1 and Lyman-break selected proto-clusters at z > 3. It is important to understand when and how the z > 3 proto-clusters evolve into passive clusters at z < 1. We aim to fill this cluster desert by using space-based N4 (4 µm) imaging …
Abundance Inhomogeneity in the Northeastern Rim of the Cygnus Loop Revealed by the Suzaku Observatory
Miller, Eric D.; Katsuda, Satoru; Uchida, Hiroyuki +5 more
We present the results of a spatially resolved spectral analysis from four Suzaku observations covering the northeastern rim of the Cygnus Loop. A two-kTe non-ionization equilibrium (NEI) model fairly well represents our data, which confirms the NEI condition of the plasma there. The metal abundances are depleted relative to the solar v…
Suzaku Observation of G359.79-0.26, a New Supernova Remnant Candidate in the Galactic Center
Mori, Hideyuki; Koyama, Katsuji; Tsuru, Takeshi Go +2 more
Utilizing Suzaku observations, we obtained the X-ray spectrum of G359.79-0.26, an extended X-ray feature nearby the Galactic center (GC) supernova remnant (SNR) SgrA East. We estimated the contribution from the Galactic center diffuse X-rays, which allows us a proper background subtraction from the faint extended source. A thin thermal plasma with…
Discovery of a Bright Transient Ultraluminous X-Ray Source, Suzaku J1305-4931 in NGC4945
Isobe, Naoki; Gandhi, Poshak; Makishima, Kazuo +5 more
An X-ray source, Suzaku J1305-4931, was discovered in the south-west arm of a nearby Seyfert II galaxy, NGC4945, at 0.5-10keV flux of 2.2×10-12erg cm-2 s-1 during a Suzaku observation conducted on 2006 January 15-17. It was undetectable in a shorter observation on 2005 August 22--23, with an upper limit of 1.7×10
Asymmetric Ejecta Distribution of the Cygnus Loop Revealed with Suzaku
Miller, Eric D.; Katsuda, Satoru; Mori, Koji +4 more
We observed a linearly sliced area of the Cygnus Loop from the north-east to the south-west with Suzaku in seven pointings. After dividing the entire fields of view (FOV) into 119 cells, we extracted spectra from all of the cells and performed spectral analysis for them. We then applied both one- and two-component non-equilibrium ionization (NEI) …
An AKARI Search for Intracluster Dust of Globular Clusters
Yamamura, Issei; Matsunaga, Noriyuki; Mito, Hiroyuki +7 more
We report on observations of 12 globular clusters with the Far-Infrared Surveyor (FIS) aboard the AKARI satellite. Our goal is to search for emission from cold dust within clusters. We detected diffuse emissions toward NGC6402 and 2808, but the IRAS 100µm maps show the presence of strong background radiation. They are likely to have been emi…