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The type I Seyfert galaxy NGC 3227 was observed by Suzaku six times in 2008, with intervals of $\sim1$ week and net exposures of $\sim50$ ksec each. Among the six observations, the source varied by nearly an order of magnitude, being…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Hirofumi Noda , Kazuo Makishima , Shin'ya Yamada , Kazuhiro Nakazawa , Soki Sakurai , Katsuma Miyake

We present the results of a joint {\it XMM-Newton} and {\it NuSTAR} campaign on the active galactic nucleus (AGN) IC 4329A, consisting of 9 $\times$ 20 ks {\it XMM-Newton} observations, and 5 $\times$ 20 ks {\it NuSTAR} observations within…

The bright type I Seyfert galaxy NGC 3516 was observed by {\it Suzaku} twice, in 2005 October 12--15 and 2009 October 28--November 2, for a gross time coverage of 242 and 544 ksec and a net exposure of 134 and 255 ksec, respectively. The…

High Energy Astrophysical Phenomena · Physics 2014-06-20 Hirofumi Noda , Kazuo Makishima , Kazuhiro Nakazawa , Shin'ya Yamada

IC 4329A is the brightest known Seyfert galaxy in hard (~2-30 keV) X-rays and is likely to be representative of Seyfert 1 galaxies as a class. A recent 100 ks BeppoSAX observation (Perola et al. 1999) clearly confirmed the presence of a…

Astrophysics · Physics 2009-10-31 M. Cappi , G. Di Cocco , M. Dadina , G. Malaguti , M. Matsuoka , G. Matt , G. C. Perola , L. Piro

We have obtained a deep, simultaneous observation of the bright, nearby Seyfert galaxy IC 4329A with Suzaku and NuSTAR. Through a detailed spectral analysis, we are able to robustly separate the continuum, absorption and distant reflection…

We report here the results of high-resolution and spectral imaging X-ray observations, with both the ROSAT HRI and PSPC, of the field surrounding the nearby Seyfert galaxy IC4329A. Many point sources are detected, the brightest being…

Astrophysics · Physics 2007-05-23 A. M. Read , W. Pietsch

We report results from a Suzaku observation of the narrow-line Seyfert 1 NGC 4051. During our observation, large amplitude rapid variability is seen and the averaged 2--10 keV flux is 8.1x10^-12 erg s^-1 cm^-2, which is several times lower…

From the spectral analysis of a broadband (0.1-200 keV) BeppoSAX observation of the Seyfert 1 galaxy IC 4329A, the main results obtained are: a) the amount of reflection, together with the intensity of the iron K line, indicate a geometry…

Astrophysics · Physics 2007-05-23 G. C. Perola

We report on the first Suzaku observation of IGR J16318-4848, the most extreme example of a new group of highly absorbed X-ray binaries that have recently been discovered by the International Gamma-Ray Astrophysics Laboratory INTEGRAL. The…

High Energy Astrophysical Phenomena · Physics 2015-05-14 L. Barragán , J. Wilms , K. Pottschmidt , M. A. Nowak , I. Kreykenbohm , R. Walter , J. A. Tomsick

In 2006 June, the obscured low luminosity active galactic nucleus in the nearby Seyfert 1.9 galaxy NGC 4258 was observed with Suzaku for ~ 100 ks. Utilizing the XIS and the HXD, the nucleus emission was detected over 2 to 40 keV range, with…

Astrophysics · Physics 2015-05-13 Shin'ya Yamada , Takeshi Itoh , Kazuo Makishima , Kazuhiro Nakazawa

We detect seven distinct absorbing systems in the high-resolution X-ray spectrum of the Seyfert 1 galaxy IC 4329A, taken with XMM-Newton. Firstly we detect absorption due to cold gas in our own Galaxy and warm gas in the Galactic halo or…

The Type I Seyfert galaxy Markarian 509 was observed with Suzaku in 2010 November, for a gross time span of 2.2 days. Timing and spectral properties of the 0.5-45 keV X-rays, detected with the XIS and HXD, consistently revealed the presence…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Hirofumi Noda , Kazuo Makishima , Shin'ya Yamada , Shunsuke Torii , Soki Sakurai , Kazuhiro Nakazawa

We obtained observations of NGC 4639 with ASCA in order to investigate its mildly active Seyfert 1 nucleus at hard X-ray energies. Koratkar et al. (1995) have previously shown that the nucleus is a pointlike source in the ROSAT soft X-ray…

We present a Suzaku observation of the dwarf Seyfert galaxy NGC4395 with an estimated black hole mass of ~10^5 Msun. Rapid and strong X-ray variability with an rms amplitude of ~60 per cent is observed in the 0.4-10 keV band with the XIS…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 K. Iwasawa , Y. Tanaka , L. C. Gallo

We observed a nearby radio galaxy, the Centaurus A (Cen A), three times with Suzaku in 2009, and measured the wide-band X-ray spectral variability more accurately than the previous measurements. The Cen A was in the active phase in 2009,…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Y. Fukazawa , K. Hiragi , S. Yamazaki , M. Mizuno , K. Hayashi , K. Hayashi , S. Nishino , H. Takahashi , M. Ohno

We have investigated spectral variation of the Seyfert 1 galaxy MCG-6-30-15 observed with Suzaku in January 2006 for three separate periods spreading over fourteen days. We found that the time-averaged continuum energy spectrum between 1…

High Energy Astrophysical Phenomena · Physics 2015-05-14 Takehiro Miyakawa , Ken Ebisawa , Yuichi Terashima , Fuminori Tsuchihashi , Hajime Inoue , Piotr Zycki

To constrain the origin of the soft X-ray excess phenomenon seen in many active galactic nuclei, the intensity-correlated spectral analysis, developed by Noda et al. (2011b) for Markarian 509, was applied to wide-band (0.5-45 keV) Suzaku…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Hirofumi Noda , Kazuo Makishima , Kazuhiro Nakazawa , Hideki Uchiyama , Shin'ya Yamada , Soki Sakurai

We report on the X-ray spectral variability of the Seyfert 1 galaxy NGC 4051 observed with the Rossi X-ray Timing Explorer (RXTE) during a 1000 day period between May 1996 and March 1999. The spectra were obtained as part of monitoring…

Astrophysics · Physics 2009-11-07 G. Lamer , I. M. McHardy , P. Uttley , K. Jahoda

We discuss the properties of the Seyfert 1.5 galaxy LB 1727, also known as 1H 0419-577, from X-ray observations obtained by ASCA and ROSAT along with optical observations from earlier epochs. ASCA shows only modest (< 20%) variations in…

A Suzaku observation of the nucleus of the radio-loud AGN Centaurus A in 2005 has yielded a broadband spectrum spanning 0.3 to 250 keV. The net exposure times after screening were: 70 ks per X-ray Imaging Spectrometer (XIS) camera, 60.8 ks…

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