Results 21 to 30 of about 1,203,775 (345)

The XMM large scale structure survey: optical vs. X-ray classifications of active galactic nuclei and the unified scheme [PDF]

, 2007
Our goal is to characterize AGN populations by comparing their X-ray and optical classifications. We present a sample of 99 spectroscopically identified X-ray point sources in the XMM-LSS survey which are significantly detected in the [2-10] keV band ...
A. Corral, A. Schwope, Akylas, Alexander, Antonucci, Aretxaga, Barcons, Bassani, Bondi, Boyle, Brandt, Burkert, C. Lonsdale, Caccianiga, Carrera, Cash, Chiappetti, Cohen, Coleman, Comastri, Comastri, D. Maccagni, Della Ceca, Dickey, Downes, Dye, E. Gosset, Eckart, Elvis, F. J. Carrera, F. Pacaud, Fiore, Fiore, Gallagher, Gandhi, Gandhi, Gandhi, Gavignaud, Gehrels, Giacconi, Gilli, Griffiths, Hickox, I. Gavignaud, J. A. Tedds, J. Ebrero, J. Surdej, Kewley, Kukula, L. Chiappetti, Lamareille, Lawrence, Le Fèvre, Le Fèvre, Lonsdale, M. J. Page, M. Krumpe, M. Pierre, M. Polletta, M. Tajer, M. Watson, Mainieri, Maiolino, Maiolino, Mateos, Moran, Murray, Nandra, O. Garcet, O. Le Fèvre, P. G. Sprimont, P. Gandhi, P. Vaisanen, Pacaud, Page, Page, Page, Page, Page, Panessa, Pappa, Perola, Pierre, Pierre, Polletta, Punsly, Ranalli, Risaliti, S. Mateos, S. Rosen, Setti, Severgnini, Severgnini, Silverman, Spergel, T. Contini, Tajer, Treister, Treister, Turner, V. Borkowski, Veilleux, W. Borczyk, Weingartner, Worsley   +104 more
core   +3 more sources

Galactic Centre X‐ray Sources [PDF]

AIP Conference Proceedings, 2007
4 pages, 3 figures; Poster to appear in AIP Conf. Proc.: `The Multicoloured Landscape of Compact Objects and their Explosive Origins'; Cefalu, Sicily, 2006 June 11 ...
Gosling, A, Bandyopadhyay, R, Blundell, K   +2 more
openaire   +3 more sources

X-ray observations of ultraluminous X-ray sources [PDF]

Astrophysics and Space Science, 2007
Invited talk at the 5th Stromlo Symposium. 10 pages, 4 figures.
openaire   +4 more sources

Luminous supersoft X-ray sources [PDF]

Astronomy & Astrophysics, 2004
We discuss possible evolution channels that lead to the formation of luminous supersoft X-ray sources, subclasses of which may be progenitors of type Ia supernovae. We carry out full evolution calculations from the zero-age main sequence to the supersoft source.
Bitzaraki, O.M., Rovithis-Livaniou, H., Tout, C.A., van den Heuvel, E.P.J.   +3 more
openaire   +4 more sources

The HELLAS2XMM survey: IV. Optical identifications and the evolution of the accretion luminosity in the Universe [PDF]

, 2003
We present results from the photometric and spectroscopic identification of 122 X-ray sources recently discovered by XMM-Newton in the 2-10 keV band (the HELLAS2XMM 1dF sample).
A. Baldi, A. Comastri, Akiyama, Alexander, Baldi, Banse, Barcons, Barger, Barger, Bertin, Brandt, Brusa, C. Vignali, Cavaliere, Comastri, Comastri, Comastri, Cowie, Della Ceca, Elvis, F. Cocchia, F. Fiore, F. La Franca, Fabian, Ferrarese, Fiore, Fiore, Fiore, Fontana, Franceschini, Franceschini, G. C. Perola, G. Matt, George, Giacconi, Giacconi, Giommi, Granato, Hartwick, Hasinger, Ho, La Franca, Laor, Lehmann, Lilly, M. Brusa, M. Mignoli, Madau, Madau, Mainieri, Menci, Mineo, Mushotzky, N. Carangelo, Oke, P. Ciliegi, P. Severgnini, R. Maiolino, S. Molendi, Schmidt, Schmidt, Setti, Ueda   +62 more
core   +5 more sources

Radial Distribution of X-ray Point Sources near the Galactic Center [PDF]

, 2009
(Abridged) We present the LogN-LogS and spatial distributions of X-ray point sources in seven Galactic Bulge (GB) fields within 4 deg from the Galactic Center (GC).
Baganoff, Bogdanov, Ebisawa, Freeman, Grindlay, Heinke, Hickox, Hong, Hong, Hong, JaeSub Hong, Jonathan E. Grindlay, Kim, Kim, Laycock, Maureen van den Berg, Muno, Muno, Muno, Muno, Muno, Murakami, Murakami, Nishiyama, Ruiter, Schlegel, Silas Laycock, Stanek, van den Berg, Wijnands   +29 more
core   +1 more source

X-ray reflection in a sample of X-ray bright Ultraluminous X-ray sources

, 2009
We apply a reflection-based model to the best available XMM-Newton spectra of X-ray bright UltraLuminous X-ray (ULX) sources (NGC 1313 X-1, NGC 1313 X-2, M 81 X-6, Holmberg IX X-1, NGC 5408 X-1 and Holmberg II X-1).
A. C. Fabian, Abolmasov, Arnaud, Blandford, Brenneman, Brown, Cackett, Colbert, Dewangan, Dickey, Fabbiano, Fabbiano, Fabian, Feng, Fryer, Fryer, George, Gladstone, Goad, Guilbert, Hadfield, Kaaret, Karachentsev, King, Kubota, Laor, Li, Liu, M. D. Caballero-García, Makishima, Mapelli, Miller, Miller, Miller, Miller, Miniutti, Miyawaki, Nandra, Paczynski, Pakull, Pakull, Reis, Reis, Remillard, Roberts, Roberts, Ross, Soria, Stobbart, Strohmayer, Tanaka, Ueda, Winter   +52 more
core   +1 more source

The Chandra Deep Field-North Survey. XIV. X-ray detected Obscured AGNs and Starburst Galaxies in the Bright Submm Source Population

, 2002
We provide X-ray constraints and perform the first X-ray spectral analyses for bright (f_850>=5mJy; S/N>=4) SCUBA sources in an 8.4'x8.4' area of the 2 Ms Chandra Deep Field-North survey containing the Hubble Deep Field-North.
A. E. Hornschemeier, Blain A. W., C. Vignali, D. M. Alexander, D. P. Schneider, Downes D., F. E. Bauer, G. Chartas, G. P. Garmire, Maiolino R., Matt G., Matt G., Rengarajan T. N., Rowan-Robinson M., S. C. Gallagher, Severgnini P., Soucail G., Vignati P., W. N. Brandt, Zezas A.   +19 more
core   +1 more source

X-ray and Optical Study of Low Core Density Globular Clusters NGC6144 and E3 [PDF]

, 2009
We report on the Chandra X-ray Observatory and Hubble Space Telescope observation of two low core density globular clusters, NGC6144 and E3. By comparing the number of X-ray sources inside the half-mass radius to those outside, we found 6 X-ray sources ...
Albert K. H. Kong, Alcaino, Bassa, Cees Bassa, Cool, Cool, David Pooley, Davies, Frank Verbunt, Freeman, Giacconi, Green, Grindlay, Grindlay, Heinke, Heinke, Hills, Kong, Lu, Pooley, Pooley, Pooley, Pryor, Sarajedini, Scott F. Anderson, Shih-Hao Lan, Verbunt, Verbunt, Verbunt, Verbunt, Walter H. G. Lewin, Wijnands   +31 more
core   +2 more sources

The X-ray binary population in M33: II. X-ray spectra and variability

, 2007
In this paper we investigate the X-ray spectra and X-ray spectral variability of compact X-ray sources for 3 Chandra observations of the Local Group galaxy M33. The observations are centered on the nucleus and the star forming region NGC 604.
A. Zezas, D.‐W. Kim, G. Fabbiano, H.‐J. Grimm, J. McDowell, Okada Y., Predehl P.   +6 more
core   +1 more source