Two Years of INTEGRAL monitoring of GRS 1915+105 Part 2: X-Ray Spectro-Temporal Analysis

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

13 pages, 8 figures (3 color), accepted for publication in ApJ, scheduled for the March 20, 2008, vol676 issue. Paper 1 is the

Scientific paper

10.1086/527372

(abridged) This is the second paper presenting the results of two years of monitoring of GRS 1915+105 with \integral and \rxte and the Ryle Telescope. We present the X-ray spectral and temporal analysis of four observations which showed strong radio to X-ray correlations. During one observation GRS 1915+105 was in a steady state, while during the three others it showed cycles of X-ray dips and spikes (followed by radio flares). We present the time-resolved spectroscopy of these cyclesand show that in all cases the hard X-ray component (the Comptonized emission from a coronal medium) is suppressed in coincidence with a soft X-ray spike that ends the cycle. We interpret these results as evidence that the soft X-ray spike is the trigger of the ejection, and that the ejected medium is the coronal material. In the steady state observation, the X-ray spectrum is indicative of the hard-intermediate state, with the presence of a relatively strong emission at 15 GHz. The X-ray spectra are the sum of a Comptonized component and an extra power law extending to energies >200 keV without any evidence for a cut-off. We observe a possible correlation of the radio flux with that of the power law component, which may indicate that we see direct emission from the jet at hard X-ray energies. We study the energy dependence of a ~4 Hz QPO during the hard-intermediate state observation. The QPO-``spectrum'' is well modeled by a power law with a cut-off at an energy about 11 keV that clearly differs from the relative contribution of the Comptonized component to the overall flux. This may rule out models of global oscillations of the Compton corona.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Two Years of INTEGRAL monitoring of GRS 1915+105 Part 2: X-Ray Spectro-Temporal Analysis does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Two Years of INTEGRAL monitoring of GRS 1915+105 Part 2: X-Ray Spectro-Temporal Analysis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Two Years of INTEGRAL monitoring of GRS 1915+105 Part 2: X-Ray Spectro-Temporal Analysis will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-681411

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.