Search Publications
X-Ray Spectral Variability of the Seyfert Galaxy NGC 4051 Observed with Suzaku
Fabian, Andrew C.; Takahashi, Tadayuki; Yamauchi, Makoto +13 more
We report on results from a Suzaku observation of the narrow-line Seyfert 1 NGC 4051. During our observation, large-amplitude rapid variability was seen, and the averaged 2--10keV flux was 8.1×10-12erg s-1cm-2, which is several times lower than the historical average. The X-ray spectrum hardens when the source flux…
Temperature and Metallicity in the Intra-Cluster Medium of Abell 262 Observed with Suzaku
Sato, Kosuke; Gastaldello, Fabio; Matsushita, Kyoko
We studied the temperature and abundance distributions of the intra-cluster medium (ICM) in the Abell 262 cluster of galaxies observed with Suzaku. Abell 262 is a bright, nearby poor cluster with an ICM temperature of ∼2keV, thus providing useful information about the connection of ICM properties between groups and clusters of galaxies. With the X…
Suzaku Observations of Metallicity Distribution in the Intracluster Medium of the NGC 5044 Group
Sato, Kosuke; Ohashi, Takaya; Matsushita, Kyoko +2 more
The metallicity distribution in the intracluster medium of the NGC 5044 group was studied up to 0.3r180 using the XIS instrument aboard the Suzaku satellite. The abundances of O, Mg, Si, S, and Fe were measured with high accuracy. The region within a radius of 0.05r180 from the center shows approximately solar abundances of M…
Suzaku Observations of SGR1900+14 and SGR1806-20
Yonetoku, D.; Mihara, T.; Yamaoka, K. +8 more
Spectral and timing studies of Suzaku ToO observations of two SGRs, 1900+14 and 1806-20, are presented. The X-ray quiescent emission spectra were well fitted by a two blackbody function or a blackbody plus a power law model. The non-thermal hard component discovered by INTEGRAL was detected by the PIN diodes and its spectrum was reproduced by the …
X-Ray Reflection Nebulae with Large Equivalent Widths of the Neutral Iron Kα Line in the Sagittarius C Region
Koyama, Katsuji; Nakajima, Hiroshi; Matsumoto, Hironori +5 more
This paper reports on the first results of a Suzaku observation in the Sgr C region. We detected four diffuse clumps with strong line emission at 6.4keV, Kα from neutral or low-ionized Fe. One of them, M359.38-0.00, was newly discovered with Suzaku. The X-ray spectra of the two bright clumps, M359.43-0.07 and M359.47-0.15, after subtracting the ga…
Hard X-Ray Spectrum from West Lobe of Radio Galaxy Fornax A Observed with Suzaku
Tashiro, M. S.; Seta, H.; Isobe, N. +2 more
An observation of the West lobe of radio galaxy Fornax A (NGC 1316) with Suzaku is reported. Since Feigelson et al. (1995) and Kaneda et al. (1995) discovered the cosmic microwave background boosted inverse-Comptonized (IC) X-rays from the radio lobe, the magnetic field and electron energy density in the lobes have been estimated under the assumpt…
Energy-Scale Calibration of the Suzaku X-Ray Imaging Spectrometer Using the Checker Flag Charge-Injection Technique in Orbit
Dotani, Tadayasu; Miller, Eric D.; Mori, Hideyuki +25 more
The X-ray Imaging Spectrometer (XIS) aboard 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 resolution in the 0.2--12keV band. Because of radiation damage in orbit, however, the charge-transfer inefficiency (CTI) has increased, and hence the energy…
Super-Hard X-Ray Emission from η Carinae Observed with Suzaku
Hamaguchi, Kenji; Ishida, Manabu; Tsujimoto, Masahiro +4 more
We present the Suzaku results of η Carinae in the 5-50keV range conducted twice around the apastron in 2005 August for 50ks and in 2006 February for 20ks. The X-ray Imaging Spectrometer (XIS) produced hard (5-12keV) band spectra, resolving K shell lines from highly ionized Fe and Ni. The Hard X-ray Detector yielded a significant detection in the s…
Nobeyama Millimeter Array Observations of the Nuclear Starburst of M 83: A GMA Scale Correlation between Dense Gas Fraction and Star Formation Efficiency
Kohno, Kotaro; Kuno, Nario; Nakanishi, Kouichiro +6 more
We present aperture synthesis high-resolution (∼7'' × 3'') observations in CO (J = 1--0), HCN (J = 1--0), and 95GHz continuum emission toward the central (∼1.5 kpc) region of the nearby barred spiral galaxy M 83 with the Nobeyama Millimeter Array. Our high-resolution CO (J = 1--0) mosaic map depicts the presence of molecular ridges along the leadi…
Uniting the Quiescent Emission and Burst Spectra of Magnetar Candidates
Yamaoka, Kazutaka; Nakagawa, Yujin E.; Yoshida, Atsumasa +1 more
Spectral studies of quiescent emission and bursts of magnetar candidates based on XMM-Newton, Chandra, and Swift data are presented. Spectra of both the quiescent emission and the burst for most magnetar candidates are reproduced by a photoelectrically absorbed two-blackbody function (2BB). There is a strong correlation between the lower and highe…