ar X iv : a st ro - p h / 97 12 23 2 v 1 1 7 D ec 1 99 7 1 The viscous disk of GRS 1915 + 105
نویسندگان
چکیده
GRS 1915+105, one of the two known galactic microquasars, shows an extremely complex variability in the X-ray band, comparable to no other X-ray source in the sky. Making use of RXTE/PCA data, we have analyzed the X-ray spectral distribution throughout the variability. We find that all variations can be attributed to the rapid appearance and disappearance of the inner region of an optically-thick accretion disk. Since the time scale for each event is related to the maximum radius of the disappearing region, the difference in time structure is due to the time distribution of such radii. The observed relation between the extent of the missing inner region of the disk and the duration of an event is in remarkable agreement with the expected radius dependence of the viscous time scale of the radiation-dominated region of an accretion disk.
منابع مشابه
X iv : a st ro - p h / 97 12 17 0 v 1 1 2 D ec 1 99 7 Thermal - viscous instabilities in the accretion disk of GRS 1915 + 105
We use data obtained with the PCA onboard RXTE to analyze the spectral variations of the black hole candidate and superluminal source GRS 1915+105. Our results suggest that despite the complicated structure of the X-ray light curve, all spectral changes observed in this source can be explained as a sudden disappearing of the inner part of the accretion disk around the compact object, followed b...
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From data obtained from the PCA in the 2-11 keV and 11-30.5 keV energy range, GRS 1915+105 is seen during RXTE observations between 1996 May and October on two separate branches in a hardness intensity diagram. On the hard branch, GRS 1915+105 exhibits narrow quasi-periodic oscillations ranging from 0.5 to 6 Hz with ∆ν ν ∼ 0.2. The QPOs are observed over intensities ranging from about 6,000 to ...
متن کاملar X iv : a st ro - p h / 99 04 08 7 v 1 7 A pr 1 99 9 QPOs and Spectral States in GRS 1915 + 105
We present results from the analysis of X-ray energy spectra and quasiperiodic oscillations (QPOs) from a set of observations which samples a broad range of time variability in GRS 1915+105. We first demonstrate that the frequency and integrated amplitude of a 0.5-10 Hz QPO is correlated with the apparent temperature of the accretion disk for the majority of observations. We then show that the ...
متن کاملar X iv : a st ro - p h / 97 06 24 4 v 1 2 4 Ju n 19 97 GRS 1915 + 105 : Flares , QPOs and other events at 15 GHz
Monitoring with the Ryle Telescope at 15 GHz of the Galactic X-ray transient source GRS 1915+105 has revealed a remarkable range of rapid and extended flares which appear to be related to the X-ray emission as recorded by the RXTE all-sky monitor. Quasi-periodic oscillations in the range 20 – 40 min have been found and are probably related to oscillations in the soft X-ray flux.
متن کاملar X iv : a st ro - p h / 03 05 10 6 v 1 7 M ay 2 00 3 The 590 days long term periodicity of the microquasar GRS 1915 + 105
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