Search Publications
The application of slim disk models to ULX: The case of M33 X-8
Cappelluti, N.; Grandi, P.; Rodriguez, J. +8 more
A comparative XMM-Newton archival data spectral study of the ultraluminous X-ray source (ULX) M33 X-8 has been performed by using both the standard disk model and the newly developed slim disk models. The results of this analysis tend to confirm the hypothesis that M33 X-8 is an X-ray binary with a stellar-mass black hole accreting at super-Edding…
Ultra-luminous sources in nearby galaxies
Mushotzky, Richard
This paper presents an update of what we have learned in the last year about the ULX phenomenon. New results are presented on radio emission from Holmberg II and a review is given on the recent X-ray data on timing and spectra. The new X-ray spectroscopic and optical imaging survey of nearby ULX with XMM allows us, for the first time, to place the…
An archival study of extended X-ray emission from classical and recurrent novae
Balman, Şölen
I discuss morphology and spectrum of the first resolved and detected classical nova shell in the X-rays - the remnant of GK Persei (1901). The existence of such a nebulosity brings about the possibility of other nova remnants emitting X-rays. I calculate that the X-ray luminosity should be about 10 26-10 33 ergs s -1
The soft and hard X-ray emission of 3C 273 from 1996 to 2004 with BeppoSAX and XMM-Newton
Staubert, R.; Deluit, S. J.; Stuhlinger, M.
We present the results of a long monitoring of the quasar 3C 273 with BeppoSAX (1996 2001) and XMM-Newton (2000 2004). Our dataset is composed of nine BeppoSAX and 15 XMM observations for a total exposure time of 855 ks (∼492 ks for BeppoSAX and ∼363 ks for XMM). In the soft X-ray domain, we investigate the 2 10 keV continuum with MECS and PN and …
X-ray observations of black-hole accretion disks
Ebisawa, Ken; Kawaguchi, Toshihiro
Our current theoretical and observational understandings of the accretion disks around Galactic black-holes are reviewed. Historically, a simple phenomenological accretion disk model has been used to interpret X-ray observations. Although such a phenomenological interpretation is still useful, high quality X-ray data from contemporary instruments …
A systematic search of highly variable X-ray sources with the XMM-Newton serendipitous survey
Yuan, Weimin; Komossa, Stefanie; Osborne, Julian P. +1 more
We describe an ongoing programme to search for X-ray sources with long-term, large amplitude X-ray variability. The method is to compare the X-ray sources from the XMM-Newton Serendipitous Survey with those from the previous ROSAT pointed observations and the ROSAT All-sky Survey. The work is largely motivated by the recent discovery of a new type…
XMM-Newton observations of low luminosity Be/X-ray candidates
Haberl, F.; Motch, C.; Janot-Pacheco, E. +2 more
A small number of early Be stars exhibit X-ray luminosities intermediate between those typical of early type stars and those radiated by Be/X-ray binaries in the quiescent state. We report on XMM-Newton observations of two such Be stars, HD 161103 and SAO 49725 which were originally discovered in a systematic cross-correlation between the ROSAT al…
FUV and X-ray grating spectra of novae and supersoft X-ray sources
Orio, M.
I review recent FUV and X-ray observations of classical and recurrent novae and supersoft X-ray sources, among them potential type Ia supernova progenitors. FUSE spectra show emission lines of O VI, which appear to be produced very close to the white dwarf of the binary system. In one case, these lines have allowed a measurement of the white dwarf…
The ultraluminous X-ray sources NGC 1313 X-1 and X-2
Falomo, R.; Treves, A.; Turolla, R. +3 more
We present a detailed analysis of XMM archival data of two Ultraluminous X-ray Sources (ULXs) in the nearby spiral galaxy NGC 1313: NGC 1313 X-1 and X-2. The spectral continuum of these sources was modeled with a soft thermal component plus a power-law. If the soft component originates from an accretion disk, the inferred mass of the compact remna…
XMM-Newton observations of faint X-ray sources in globular clusters
Webb, N. A.; Barret, D.; Gendre, B.
Using the new generation of X-ray observatories, we are now beginning to identify populations of close binaries in globular clusters, previously elusive in the optical domain because of the high stellar density. These binaries are thought to be, at least in part, responsible for delaying the inevitable core collapse of globular clusters and their …