Conveners
Parallel 9: AGN-III
- Andrew Chen
Fermi-LAT has detected more than 3700 gamma-ray blazars, confirming that they are the
largest group of high-energy gamma-ray emitters. In gamma-ray astronomy it is therefore crucial to understand their emission mechanisms and their population properties. In the same way they are also fundamental for indirect studies on topics such as the extragalactic background light and searches for the...
It is characteristic of multi-wavelength blazar variability to exhibit temporal signatures of coloured noise. We therefore simulate multi- wavelength blazar variability by means of time-dependent blazar modeling and introduce different generated sets of coloured noise variations. The different sets of variations specifically cover a spectrum of pure power law indices in temporal frequency...
The broadband emission in the blazar is highly anisotropic and non-thermal boosted along the jet axis and dominated by red noise. Any kind of periodic signature in their light curve is buried in the red noise and therefore a sophisticated method is required to detect them if they are present. Recently, the presence of a QPO signal is proposed or detected in the gamma-ray light curve of many...
This project investigates a new methodology to search for periods in light-curves of high-energy gamma-ray sources such as Active Galactic Nuclei (AGNs). High-energy light curves have significant stochastic components, making period detection somewhat challenging.
In our first model, periodic terms , drifts of the light-curves and random walk with correlation between flux points due to...
In this study, we systematically studied the X-ray to GeV gamma-ray spectra of 61 {\it Fermi} Large Area Telescope (LAT) detected radio galaxies. We found an anticorrelation between peak frequency and peak luminosity in the high-energy spectral component of radio galaxies, similar to blazars. With this sample, we also constructed a gamma-ray luminosity function (GLF) of gamma-ray-loud radio...
Motivated by the detection of a hardening in the γ-ray spectrum from the core of the radio galaxy Centaurus A, this work focuses on the findings of Fermi-LAT observations of radio galaxies to search for similar spectral features. This includes discussion of a number of radio galaxy γ-ray spectral energy distributions to uncover any common characteristics amongst the Fermi-LAT-detected radio...
The Hydra A radio galaxy is the result of one of the most powerful AGN outbursts known to date. It hosts a pair of 300- kiloparsec diameter radio lobes that have been inflated over multiple generations of activity. Radio observations provide us with a unique perspective for investigating and studying the high-energy particles that reside in the radio lobes. The MeerKAT radio telescope carried...
