Search Publications
Universal profiles of the intracluster medium from Suzaku X-ray and Subaru weak-lensing observations*
Sato, Kosuke; Fukazawa, Yasushi; Nakazawa, Kazuhiro +16 more
We conduct a joint X-ray and weak-lensing study of four relaxed galaxy clusters (Hydra A, A 478, A 1689, and A 1835) observed by both Suzaku and Subaru out to virial radii, with the aim of understanding recently discovered unexpected features of the intracluster medium (ICM) in cluster outskirts. We show that the average hydrostatic-to-lensing tot…
Discovery of recombining plasma in the supernova remnant 3C 391
Takahashi, Tadayuki; Koyama, Katsuji; Nakashima, Shinya +2 more
Recent X-ray study of middle-aged supernova remnants (SNRs) reveals strong radiative recombination continua (RRCs) associated with overionized plasmas, which origin still remains uncertain. We report a discovery of an RRC in the middle-aged SNR 3C 391. If the X-ray spectrum is fitted with a two-temperature plasma model in collisional ionization eq…
Firm detection of a cyclotron resonance feature with Suzaku in the X-ray spectrum of GRO J1008-57 during a giant outburst in 2012
Makishima, Kazuo; Sasano, Makoto; Mihara, Tatehiro +3 more
We report on the firm detection of a cyclotron resonance scattering feature (CRSF) in the X-ray spectrum of the Be X-ray binary pulsar, GRO J1008-57, achieved by the Suzaku Hard X-ray Detector during a giant outburst which was detected by the MAXI Gas Slit Camera in 2012 November. The Suzaku observation was carried out on 2012 November 20, outburs…
Abundances in the ejecta of core-collapse supernova remnants G350.1-0.3 and G349.7+0.2
Koyama, Katsuji; Uchida, Hiroyuki; Yasumi, Masato +5 more
We present Suzaku results of the two Galactic supernova remnants (SNRs) G350.1-0.3 and G349.7+0.2. We find Al and Ni Kα lines from both the SNRs for the first time, in addition to previously detected K-shell lines of Mg, Si, S, Ar, Ca, and Fe. The spectra are well described by two optically thin thermal plasmas: a low-temperature (low-kT) plasma i…
O I fluorescent line contamination in soft X-ray diffuse background obtained with Suzaku/XIS
Mitsuda, Kazuhisa; Yamasaki, Noriko Y.; Takei, Yoh +1 more
The quantitative measurement of O VII line intensity is a powerful method for understanding the soft X-ray diffuse background. By systematically analyzing the O VII line intensity in 145 high-latitude Suzaku/XIS observations, the flux of O I fluorescent line in the XIS spectrum, contaminating the O VII l…
Temperature and entropy profiles to the virial radius of the Abell 1246 cluster observed with Suzaku
Sato, Kosuke; Ohashi, Takaya; Yamasaki, Noriko Y. +2 more
We report properties of the intracluster medium (ICM) in Abell 1246 to the virial radius (r200) and further outside as observed with Suzaku. The ICM emission is clearly detected to r200, and we derive profiles of electron temperature, density, entropy, and cluster mass based on the spectral analysis. The temperature shows var…
Suzaku view of the neutron star in the dipping source 4U 1822-37
Enoto, Teruaki; Makishima, Kazuo; Zhang, Zhongli +2 more
The dipping X-ray source 4U 1822-37 was observed by Suzaku on 2006 October 20 for a net exposure of 37 ks. The source was detected with the XIS at a 1-10 keV flux of 5.5 × 10-10 erg cm-2 s-1, and with the HXD (HXD-PIN) at a 10-50 keV flux of 8.9 × 10-10 erg cm-2 s-1. With HXD-PIN, t…
Structual study of Galactic hot gas toward Markarian 421 from X-ray absorption and emission lines
Mitsuda, Kazuhisa; Yamasaki, Noriko Y.; Wang, Q. Daniel +4 more
We present a structural study of the hot ISM in the Galactic halo along the sight line toward the bright active galactic nucleus Mkn 421. The O VII and O VIII absorption lines were measured with the Low Energy Transmission Grating Spectrograph aboard Chandra toward Mkn 421; the O VII and O VIII emission lines were observed in the adjacent fields o…
Probing the accretion scheme of the dipping X-ray binary 4U 1915-05 with Suzaku
Makishima, Kazuo; Zhang, Zhongli; Sasano, Makoto +2 more
The dipping low-mass X-ray binary 4U 1915-05 was observed by Suzaku on 2007 November 8 for a net exposure of 39 ks. It was detected by the XIS with a 0.8-10 keV signal rate of 9.84 ± 0.01 cts s-1 per camera, and HXD-PIN with a 12-45 keV signal rate of 0.29 ± 0.01 cts s-1. After removing the periodic dips and an X-ray burst, t…
Suzaku discovery of Fe K-shell line from the O-rich SNR G292.0+1.8
Katsuda, Satoru; Koyama, Katsuji; Uchida, Hiroyuki +7 more
We report the Suzaku/XIS results of the Galactic oxygen-rich supernova remnant G292.0+1.8, a remnant of a core-collapse supernova. The X-ray spectrum of G292.0+1.8 consists of two types of plasma, one is in collisional ionization equilibrium (CIE) and the other is in non-equilibrium ionization (NEI). The CIE plasma has nearly solar abundances, and…