Volume 365, Number 1, January 2001
First Results from XMM-Newton
|Page(s)||L152 - L157|
|Published online||15 January 2001|
The variable XMM-Newton spectrum of Markarian 766*
Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey, RH5 6NT, UK
2 Instituto de Física de Cantabria (Consejo Superior de Investigaciones Científicas-Universidad de Cantabria), 39005 Santander, Spain
3 Science Operations Centre, Astrophysics Division, ESA Space Science Department, PO Box 50727, 28080 Madrid, Spain
4 Space Research Organization of The Netherlands, Laboratory for Space Research, Sorbonnelaan 2, Utrecht, CA 3584, The Netherlands
5 Astrophysikalisches Institut Potsdam, Sternwarte 16, 14482 Potsdam, Germany
6 NASA Goddard Space Flight Center, Code 660, Greenbelt, MD 20771, USA
7 X-Ray Astronomy Group, Department of Physics and Astronomy, Leicester University, Leicester LE1 7RH, UK
8 Los Alamos National Laboratory, NIS-2, Los Alamos, NM 87545, USA
Corresponding author: M. J. Page, firstname.lastname@example.org
Accepted: 10 November 2000
The narrow-line Seyfert 1 galaxy Mrk 766 was observed for 60 ks with the XMM-Newton observatory. The source shows a complex X-ray spectrum. The 2-10 keV spectrum can be adequately represented by a power law and broad Fe Kα emission. Between 0.7 and 2 keV the spectrum is harder and exhibits a flux deficit with respect to the extrapolated medium energy slope. Below 0.7 keV, however, there is a strong excess of emission. The RGS spectrum shows an edge-like feature at 0.7 keV; the energy of this feature is inconsistent with that expected for an OVII edge from a warm absorber. Mrk 766 varies by a factor of ~2 in overall count rate in the EPIC and RGS instruments on a timescale of a few thousand seconds, while no significant flux changes are observed in the ultraviolet with the OM. The X-ray variability is spectrally dependent with the largest amplitude variability occurring in the 0.4-2 keV band. The spectral variability can be explained by a change in flux and slope of the medium energy continuum emission, superimposed on a less variable (or constant) low energy emission component.
Key words: accretion, accretion disks / black hole physics / galaxies: Seyfert / X-rays: general
© ESO, 2001
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.