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Related papers: Is there a hard tail in the Coma Cluster X-ray spe…

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Chandra X-ray observations of the high redshift (z =1.532) radio-loud quasar 3C270.1 in 2008 February show the nucleus to have a power-law spectrum, Gamma = 1.66 +/- 0.08, typical of a radio-loud quasar, and a marginally-detected Fe Kalpha…

We present the preliminary results of a survey that makes use of several deep exposures obtained with the X-Ray telescopes of the BeppoSAX satellite. The survey limiting sensitivity is 5 x 10^-14 cgs in the 2-10 keV band and 7 x 10^-14 cgs…

Astrophysics · Physics 2011-02-11 P. Giommi , F. Fiore , D. Ricci , S. Molendi , M. C. Maccarone , A. Comastri

We have undertaken a search for the infrared emission from the intracluster dust in the Coma cluster of galaxies by the Multiband Imaging Photometer for Spitzer. Our observations yield the deepest mid and far-infrared images of a galaxy…

Astrophysics of Galaxies · Physics 2011-02-11 T. Kitayama , Y. Ito , Y. Okada , H. Kaneda , H. Takahashi , N. Ota , T. Onaka , Y. Y. Tajiri , H. Nagata , K. Yamada

We have analyzed a long-term database for Sco X-1 obtained with the telescope IBIS onboard the INTEGRAL satellite in order to study the hard X-ray behavior of Sco X-1 from 20 up to 200 keV. Besides the data used for producing of the…

High Energy Astrophysical Phenomena · Physics 2015-06-12 T. Maiolino , F. D'Amico , J. Braga

We present BeppoSAX observations of the Seyfert 1.8 galaxy NGC1365 in the 0.1--100 keV range. The source was 6 times brighter than during an ASCA observation 3 years earlier. The 4--10 keV flux is highly variable during the BeppoSAX…

Astrophysics · Physics 2007-05-23 G. Risaliti , R. Maiolino , L. Bassani

Using 2.5 Ms of data obtained by the INTEGRAL satellite in 2003-2004, we discovered persistent hard X-ray emission from the soft gamma-ray repeater SGR 1900+14. Its 20-100 keV spectrum is well described by a steep power law with photon…

Astrophysics · Physics 2009-11-11 D. Gotz , S. Mereghetti , A. Tiengo , P. Esposito

The Coma cluster is one of the nearest galaxy clusters, and the first one in which a radio halo and a peripheral relic were discovered. While its halo and the central parts of the intracluster medium have been studied extensively, X-ray…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 G. A. Ogrean , M. Brüggen

Mkn 841 has been observed simultaneously by XMM and BeppoSAX in January 2001. Due to operational contingency, the 30ks XMM observation was split into two parts, separated by about 15 hours. We first report the presence of a narrow iron line…

We report optical, radio and X-ray observations of the Narrow-Line Seyfert 1 galaxy RX J1702.5+3247. The soft (0.1-2 keV) X-ray flux, measured by BeppoSAX, is characterized by strong variability on short time scales (< 500 sec). The most…

Astrophysics · Physics 2009-11-06 M. Gliozzi , W. Brinkmann , S. A. Laurent-Muehleisen , E. C. Moran , J. Whalen

We have searched for the 3.55 keV line from sterile neutrino decay using 3.1 megaseconds of RXTE cluster data. A 2.5$\sigma$ excess of emission over a thermal model is found over the energy span of the 3.55 keV line in the combined spectra…

High Energy Astrophysical Phenomena · Physics 2026-04-24 Mark J. Henriksen

We have used the upgraded Giant Metrewave Radio Telescope to map the Coma cluster of galaxies at 250-500 MHz and 1050-1450 MHz bands. These 6.26 arcsec and 2.18 arcsec resolutions observations allow detailed radio structures to be…

Astrophysics of Galaxies · Physics 2021-06-01 Dharam V. Lal

The X-ray luminous quasar GB 1428+4217 at redshift 4.72 has been observed with ASCA. The observed 0.5-10 keV flux is 3.2E-12 erg/s/cm2. We report here on the intrinsic 4-57 keV X-ray spectrum, which is very flat (photon index of 1.29). We…

Astrophysics · Physics 2009-10-30 A. C. Fabian , K. Iwasawa , A. Celotti , W. N. Brandt , R. G. McMahon , I. M. Hook

We examine the constraints imposed by Faraday rotation measures of extragalactic point sources on the structure of the magnetic field in the halo of our Galaxy. Guided by radio polarization observations of external spiral galaxies, we look…

Astrophysics of Galaxies · Physics 2017-03-29 Philippe Terral , Katia Ferriere

We present the results of Suzaku observation of the radio halo cluster Abell 2319. The metal abundance in the central cool region is found to be higher than the surrounding region, which was not resolved in the former studies. We confirm…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Chika Sugawara , Motokazu Takizawa , Kazuhiro Nakazawa

We report on deep XMM-Newton observations of the vertex filament in the southern giant lobe of the Fanaroff-Riley class I radio galaxy Centaurus A. We find no X-ray excess from the filament region and place a 3 sigma upper limit on the 1…

Astrophysics of Galaxies · Physics 2015-10-28 Sarka Wykes , Martin J. Hardcastle , Judith H. Croston

Several deep PSPC observations of the Coma cluster reveal a very large-scale halo of soft X-ray emission, substantially in excess of the well known radiation from the hot intra-cluster medium. The excess emission, previously reported in the…

Astrophysics · Physics 2009-11-07 M. Bonamente , M. K. Joy , R. Lieu

The bright X-ray selected BL Lac object 1ES1101--232 shows a flat X-ray spectrum, making it detectable with high statistics over the wide BeppoSAX energy range. We have observed it in two different epochs with BeppoSAX, and found a…

We have monitored a sample of 27 nearby globular clusters in the hard X-ray band (20-120 keV) for approximately 1400 days using the BATSE instrument on board the Compton Gamma-Ray Observatory. Globular clusters may contain a large number of…

Astrophysics · Physics 2009-10-28 E. Ford , P. Kaaret , B. A. Harmon , M. Tavani , S. N. Zhang

We present the results of a deep (1.1 Ms) observation of the Coma cluster of galaxies in the 18-30 keV band with the IBIS/ISGRI imager on board the INTEGRAL satellite. We show that the source extension in the North-East to South-West (SW)…

Astrophysics · Physics 2007-10-25 D. Eckert , N. Produit , A. Neronov , T. J. -L. Courvoisier

This paper reports the X-ray spectral analysis of 5 high-redshift (z \ge 2) radio-quiet quasars observed by ASCA. A simple power law continuum plus cold Galactic absorption model well fits all the spectra (tipically between $\sim$ 2-30 keV…

Astrophysics · Physics 2009-10-31 C. Vignali , A. Comastri , M. Cappi , G. G. C. Palumbo , M. Matsuoka , H. Kubo
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