Abstract Details

Name: Neeraj Kumari
Affiliation: Physical Research Laboratory
Conference ID: ASI2020_426
Title : Variability and correlation study of Mrk 509 in UV/optical & X-ray
Authors and Co-Authors : Neeraj Kumari, Sachindra Naik, Main Pal
Abstract Type : Poster
Abstract Category : Extragalactic Astronomy
Abstract : Large flux variations on the timescales of hours to years are very common in active galactic nuclei (AGNs). There are different proposed physical mechanisms for these variabilities which depend on the timescales of the processes. Longer timescale variations of the order of months to years may belong to the propagation fluctuations in the accretion disk while short term variations are generally associated with inverse-Comptonization or reprocessing of shorter wavelength radiation into longer wavelength. We aim for a detailed variability study of Seyfert 1 galaxy Mrk 509 (z = 0.034076) in UV/optical and X-ray energy range and to find the correlation between them to identify the dominating physical process going on in the system. This object is being monitored with SWIFT satellite since 2006 at irregular intervals. A large number of observations and simultaneous look of the source in UV/optical & X-ray, covering many epochs, gives us the opportunity for a detailed analysis in terms of long as well as short term variability. We use about 292 pointing observations to study the variability in six UV/optical and X-ray (0.3-10 keV) band. The X-ray spectra during the variability are well described by a model consisting of an absorbed power law and blackbody in soft band (0.3-1.0 keV). Using correlation analysis, we can test the existing assumptions in the standard Shakura-Sunyaev disk. If we obtain a different time-lag between X-ray and UV/Optical than theoretically estimated time-lag, we can infer the physical size of the accretion disk.