Dortmund 2021 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

T: Fachverband Teilchenphysik

T 83: Gamma astronomy II

T 83.4: Talk

Thursday, March 18, 2021, 16:50–17:05, Th

Long-term Studies of the Blazar Mrk 421 in the Multi-Wavelength Context — •Bernd Schleicher for the FACT and MAGIC collaboration — University of Würzburg, Institute for Theoretical Physics and Astrophysics

The blazar Mrk 421 is one of the brightest sources in very-high-energy (VHE) gamma rays. The origin of such gamma rays is still under debate but several models predict correlation between different wavelengths. Therefore, regular multi-wavelength (MWL) campaigns have been carried out, since 2009. Based on this extensive data sample, variability is studied on different time scales from minutes to years. At VHE, the source is regularly monitored by MAGIC and FACT. Combining the data from these two telescopes, both the short time scales (excellent sensitivity of MAGIC) and long time scales (dense monitoring by FACT) can be studied in detail. Studying 5.5 years of FACT light curves combined with MWL data show a correlation between VHE and X-ray with a lag < 0.6 days and a correlation between GeV gamma-ray and radio data with a lag of 43 days. A study of two years of data including both MAGIC and FACT in the VHE also shows a significant correlation between X-ray and VHE. The highest variability was found in X-rays and VHE in both studies. The analysis of further MWL observations is ongoing.