A Time Resolved View of the X-Ray Spectral Variability of the Seyfert-1 Galaxy ESO 511-G030

Abstract

Abstract The origin of the Soft X-ray excess in the spectra of several nearby active galactic nucleus is still highly debated. In this work we report the monotonic spectral hardening of a nearby bare Seyfert galaxy ESO 511-G030 over a time period of ∼110 ks. We found that both the soft (0.3–2  keV) and the hard X-ray (2–10  keV) bands have shown interesting variability during the 110 ks observation. The soft X-ray flux shows a sharp drop in the last ∼50 ks, by ∼30%, while the hard X-ray flux initially increased and then decreased. The overall effect of these variations is a monotonic increase in the hardness ratio. We conclude that: (A) The soft X-ray flux variations may be related to the changes in the primary hard X-ray. (B) The soft X-ray flux decreases by ∼36% in a timespan of ∼50 ks, indicating that its origin could be from a region as close as <0.5 light-day from the supermassive black hole. A detailed hardness ratio resolved spectral analysis with state-of-the-art reflection models will be reported in a future paper.