Abstract Details

Name: Aditi Agarwal
Affiliation: IIA, Bengaluru
Conference ID: ASI2019_498
Title : Multiwavelength studies of blazars over diverse timescales
Authors and Co-Authors : Aditi Agarwal (IIA, Bangalore), G. C. Anupama (IIA, Bangalore), C. S. Stalin (IIA, Bangalore), A. Mangalam (IIA, Bangalore), P. Mohan (SHAO, China), Markus Boettcher (Centre for Space Research, South Africa)
Abstract Type : Poster
Abstract Category : Extragalactic Astronomy
Abstract : Blazars are characterized with luminous core, rapid variability over entire electro magnetic (EM) spectra, high radio to optical polarization, superluminal motion, non thermal emission and a Doppler boosted relativistic jet pointing < 10 degrees with the line of sight (LOS). To provide a detailed understanding of blazar and its environment, we study variability over diverse timescales using various statistical methods. As optical flux variations in blazars are often followed by spectral changes, thus we examine their colour – magnitude relationship on diverse timescales which helps us to understand the origin of variability. Flux variations in different frequencies may or may not be correlated. Thus search for the presence or absence of correlation among multiple frequencies, characteristic variability timescales in the light curves or a quasi-periodic oscillation (QPO) can be used to infer the origin of variability, constraint the size of emitting region and also derive SMBH mass. For this, we have developed a suite of time series analysis techniques namely, Structure Function, Discrete Correlation Function, Lomb-Scargle periodogram, Wavelet analysis and Power Spectral Density which we apply to analyze blazar light curves. Further, to study the core-jet morphology of blazars, we developed a piecewise Gaussian fit analysis technique. Using this, we are able to find spectral indices, time lags, core position offset, core radius, mean magnetic field strength, and other jet parameters. In essence, we explore complex phenomena governing blazars through the analysis of observational data and its applications using various theoretical models which further helps us to understand the physics of the inner regions of blazars.