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An X-ray spectral study of the origin of reflection features in bare Seyfert 1 galaxy ESO 511--G030

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 نشر من قبل Ritesh Ghosh
 تاريخ النشر 2020
  مجال البحث فيزياء
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The reprocessed X-ray emission from Active Galactic Nuclei (AGN) is an important diagnostic tool to study the dynamics and geometry of the matter surrounding the supermassive black holes (SMBHs). We present a broadband (optical-UV to hard X-ray) spectral study of the bare Seyfert 1 galaxy, ESO~511--G030, using multi-epoch Suzaku and XMM-Newton data from 2012 and 2007 respectively. The broadband spectra of ESO~511--G030 exhibit a UV bump, a prominent soft-excess below 2 keV, a relatively broad ($sigma=0.08 - 0.14$ keV) Fe emission line at 6.4 keV and a weak Compton hump at E > 10 keV. The soft X-ray excess in ESO~511--G030 can be described either as the thermal Comptonization of disk seed photons by a warm ($0.40^{+0.02}_{-0.02}$ keV), optically thick ($tau = 12.7^{+0.5}_{-0.4}$) and compact ($< 15 rm r_{g}$) corona or as the blurred reflection from an untruncated and moderate to highly ionized accretion disk. However, for the blurred reflection, the model requires some extreme configuration of the disk and corona. Both these models prefer a rapidly spinning black hole ($a>0.78$) and a compact corona, indicating a relativistic origin of the broad Fe emission line. We found an inner disk temperature of $sim 2-3$ eV that characterises the UV bump and the SMBH accretes at a sub-Eddington rate ($lambda_{Edd} = 0.004-0.008$).

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