The Long Term X-Ray Variability of Quasars
| Main Authors: | Middei, Riccardo, Vagnetti, F., Bianchi, S., La Franca, F., Paolillo, M. |
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| Format: | info Proceeding Journal |
| Terbitan: |
, 2016
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/163794 |
Daftar Isi:
- We present the analysis of the ensemble structure function of the soft X-ray variability on a sample of about 3000 quasars. Our data are based on the observations of the ROSAT and XMM-Newton satellites, cross-correlated with the Sloan Digital Sky Survey Quasar catalogue. We measure for the first time the structure function up to a rest-frame time interval as large as 20 years (the longest time interval investigated through this type of study). The results of our analysis show that the X-ray variability of quasars still increases at these long time lags. This will be discussed in relation to the physical size of the emitting region.