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Related papers: SHEEP: the ASCA 5-10 keV survey

200 papers

A review of recent developments in the field of X-ray surveys, especially in the hard (2-10 and 5-10 keV) bands, is given. A new detailed comparison between the measurements in the hard band and extrapolations from ROSAT counts, that takes…

Astrophysics · Physics 2007-05-23 P. Giommi , F. Fiore , M. Perri

We present an ASCA discovery of diffuse hard X-ray emission from the Sgr C complex with its peak in the vicinity of the molecular cloud core. The X-ray spectrum is characterized by a strong 6.4-keV line and large absorption. These…

Astrophysics · Physics 2009-10-31 H. Murakami , K. Koyama , M. Tsujimoto , Y. Maeda , M. Sakano

ASCA observations of the Seyfert 2 galaxy NGC 7582 revealed it was highly variable on the timescale of $\sim2\times10^4$ s in the hard X-ray (2-10 keV) band, while the soft X-ray (0.5-2 keV) flux remained constant during the observations.…

Astrophysics · Physics 2015-06-24 S. -J. Xue , C. Otani , T. Mihara , M. Cappi , M. Matsuoka

The INTEGRAL satellite, during its regular scanning observations of the Galactic plane, has discovered several new X-ray sources emitting above 20 keV. The nature of the great majority of them is still unknown. Here we report on the likely…

Astrophysics · Physics 2009-11-10 L. Sidoli , S. Vercellone , S. Mereghetti , M. Tavani

We present 0.5 -160 micron Spectral Energy Distributions (SEDs) of galaxies, detected at 70microns with the Multiband Imaging Photometer for Spitzer (MIPS), using broadband imaging data from Spitzer and ground-based telescopes.…

We present results of the ASCA observation of the Seyfert 2 galaxy NGC 4507. The 0.5-10 keV spectrum is rather complex and consists of several components: (1) a hard X-ray power law heavily absorbed by a column density of about 3 10^23…

Astrophysics · Physics 2009-10-30 A. Comastri , C. Vignali , M. Cappi , G. Matt , R. Audano , H. Awaki , S. Ueno

We follow up on a report by Vacca et al. (2018) of 28 candidate large-scale diffuse synchrotron sources in an 8{\deg}$\times$8{\deg} area of the sky (centred at RA 5h0m0s Dec 5{\deg}48'0''). These sources were originally observed at 1.4 GHz…

Astrophysics of Galaxies · Physics 2022-05-27 Torrance Hodgson , Melanie Johnston-Hollitt , Benajmin McKinley , Tessa Vernstrom , Valentina Vacca

We present a comprehensive catalog of 251 potential counterparts for 250 unassociated hard X-ray sources detected in the Swift Burst Alert Telescope (BAT) 150-month hard X-ray survey. Over 150 months of observation, BAT has detected 2339…

High Energy Astrophysical Phenomena · Physics 2026-04-29 K. Imam , N. Torres-Alba , S. Marchesi , M. Ajello , S. Joffre , I. Cox , A. Pizzetti , X. Zhao , A. Segreto , A. Banerjee , I. Pal , V. E. Gianolli , D. Stern

We review observations and theoretical models of X-ray/gamma-ray spectra of radio-quiet Seyfert galaxies and of Galactic black-hole candidates (in the hard spectral state). The observed spectra share all their basic components: an…

In this paper we report the discovery of an hard X-ray selected Type 2 Seyfert galaxy and we present and discuss its X-ray and optical spectrum together with the radio to X-ray energy distribution. The X-ray source - AXJ2254+1146 - is part…

Astrophysics · Physics 2007-05-23 R. Della Ceca , T. Maccacaro , P. Rosati , V. Braito

The X-ray spectrum of the Seyfert 1.5 source NGC 6860 is among the most complex of the sources detected in the Swift Burst Alert Telescope all-sky survey. A short XMM-Newton follow-up observation of the source revealed a flat spectrum both…

High Energy Astrophysical Phenomena · Physics 2015-05-19 Lisa M. Winter , Richard Mushotzky

The results from an X-ray spectral analysis of a large sample of quasars, observed with ASCA, are presented. Data reduction leaves 62 quasars, 35 radio-loud and 27 radio-quiet, suitable for spectral analysis. Differences are found between…

Astrophysics · Physics 2009-10-31 James Reeves , Martin Turner

We present the Spitzer 10-37um IRS high resolution (R~600) spectroscopic survey of the Seyfert galaxies of the 12 micron Galaxy Sample. The new spectra of 61 galaxies, with those already published, gives us a total of 91 12micron Seyfert…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Silvia Tommasin , Luigi Spinoglio , Matthew A. Malkan , Giovanni Fazio

SHADES is a new, major, extragalactic sub-mm survey currently being undertaken with SCUBA on the JCMT. The aim of this survey is to map 0.5 square degrees of sky at a depth sufficient to provide the first, major (~300 source), unbiased…

Astrophysics · Physics 2015-11-11 James S. Dunlop

The spectroscopic analysis of 117 serendipitous sources in the HELLAS2XMM 1df (1 degree field) survey is described. Of these, 106 sources, of which 86% have a spectroscopic redshift, are used to evaluate the fraction of X-ray absorbed (log…

The results of spectropolarimetry surveys of obscured AGNs are reviewed, paying special attention to their implications for the existence of two populations of type 2 Seyfert galaxies -- hidden Seyfert 1s and "true" Seyfert 2s. In this…

Astrophysics · Physics 2007-05-23 Edward C. Moran

We found diffuse hard X-ray sources, G11.0+0.0, G25.5+0.0, and G26.6-0.1 in the ASCA Galactic plane survey data. The X-ray spectra are featureless with no emission line, and are fitted with both models of a thin thermal plasma in…

Astrophysics · Physics 2009-11-07 Aya Bamba , Masaru Ueno , Katsuji Koyama , Shigeo Yamauchi

(abridged) We present an analysis of the deepest hard X-ray survey to date of about 2500 deg^2 performed by the IBIS instrument on board INTEGRAL in the 20-60 keV band, with a total exposure time of 4 Ms. We find 34 candidate sources. The…

Astrophysics · Physics 2009-11-13 S. Paltani , R. Walter , I. M. McHardy , T. Dwelly , C. Steiner , T. J. -L. Courvoisier

We present new BeppoSAX LECS, MECS and PDS observations of five lobe-dominated, broad-line active galactic nuclei selected from the 2-Jy sample of southern radio sources. These include three radio quasars and two broad-line radio galaxies.…

We present the Swift optical to X-ray spectral energy distributions (SEDs) of 44 quasars at redshifts z~2 observed by Swift, part of a larger program to establish and characterize the optical through X-ray SEDs of moderate-redshift quasars.…

Astrophysics of Galaxies · Physics 2017-02-20 Daniel Lawther , Marianne Vestergaard , Sandra Raimundo , Dirk Grupe