Blazars represent a subset of AGN with relativistic jets where the direction of a jet lies very close to our line of sight. The highly Doppler boosted emission from the blazar’s jet results in high apparent luminosities, and blazars display variability on periods from less than one day up to years. At optical wavelengths, the observed emission of the blazar is a superposition of the polarized...
This work provides the description of charged particle transport in magnetic fields via a correlated random walk of particles and derives a telegraph transport equation from first principles that describe the initial, ballistic, and later diffusive phases in a consistent manner. A novel high-performance numerical method based on the theoretical considerations is presented that propagates...
The spectral energy distribution of radio-loud AGN have a characteristic double bump structure, with emission at the lower wavelengths being dominated by synchrotron radiation from non-thermal electrons in relativistic jets. To investigate how the radio emission of these sources relate to the dynamical structure of the relativistic jets we model the synchrotron emission by using 3D hybrid...
We present results of an optical variability study of 44 newly identified blazar candidates behind the Magellanic Clouds. The sample contains candidates for 27 flat spectrum radio quasars (FSRQs) and 17 BL Lacertae objects (BL Lacs), with nine of them recognized as blazars, while the classification of the remaining objects is still uncertain. All objects possess high photometric accuracy and...
S5 1803+784 is a BL Lac object. Unlike most low synchrotron peaked (LSP) blazars, the spectrum of S5 1803+784 is poorly fitted with a single zone synchrotron self-Compton (SSC) leptonic jet model. This could be why recent multiwavelength studies show no clear correlation between the synchrotron emission and the gamma-ray emission in this blazar. We utilize a simple single-zone leptonic jet...
Blazars are a class of Active Galactic Nuclei (AGN) that are radio loud and have a small angle between the jet and the observer’s line of sight. In some cases, flaring events in one frequency band are not accompanied by flaring in other bands. Such events are termed orphan flares. The causes of this variabil- ity and conditions in and location of the high energy emission region are not...
The third observation run (O3) of Advanced LIGO and Advanced Virgo started in April 2019 and ended in March 2020, with improved sensitivities compared to the previous observing run. The presentation will review the science results achieved during the O3 run, that include the GWTC-2, GWTC-2.1 catalogs of compact binary mergers and some exceptional events: GW190412, the merger of two black holes...