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Relentless multi-wavelength variability of Mrk 421 and Mrk 501
(2022)PoS: Proceedings of Science ~ Proceedings of 37th International Cosmic Ray ConferenceMrk 421 and Mrk 501 are two close, bright and well-studied high-synchrotron-peaked blazars, which feature bright and persistent GeV and TeV emission. We use the longest and densest dataset of unbiased observations of these two sources, obtained at TeV and GeV energies during five years with FACT and Fermi-LAT. To characterize the variability and derive constraints on the emission mechanism, we augment the dataset with contemporaneous ...Conference Paper -
The Southern Wide-field Gamma-ray Observatory reach for Primordial Black Hole evaporation
(2022)PoS: Proceedings of Science ~ Proceedings of 37th International Cosmic Ray ConferenceThe Southern Wide-field Gamma-ray Observatory (SWGO) is a proposed ground-based gamma-ray detector that will be located in the Southern Hemisphere and is currently in its design phase. In this contribution, we will outline the prospects for Galactic science with this Observatory. Particular focus will be given to the detectability of extended sources, such as gamma-ray halos around pulsars; optimisation of the angular resolution to mitigate ...Conference Paper -
Benchmarking the Science for the Southern Wide-Field Gamma-ray Observatory (SWGO)
(2022)PoS: Proceedings of Science ~ Proceedings of 37th International Cosmic Ray ConferenceThe Southern Wide-field Gamma-ray Observatory (SWGO) is the project to build a new extensive air shower particle detector for the observation of very-high-energy gamma-rays in South America. SWGO is currently planned for installation in the Southern Hemisphere, which grants it a unique science potential among ground-based gamma-ray detectors. It will complement the capabilities of CTA, working as a wide-field instrument for the monitoring ...Conference Paper -
Multi-wavelength study of Mrk 421 during a TeV flare
(2022)PoS: Proceedings of Science ~ 37th International Cosmic Ray Conference (ICRC 2021)The blazar Mrk 421 shows frequent, short flares in the TeV energy regime. Due to the fast nature of such episodes, we often fail to obtain sufficient simultaneous information about flux variations in several energy bands. To overcome this lack of multi-wavelength (MWL) coverage, especially for the pre- and post-flare periods, we have set up a monitoring program with the FACT telescope (TeV energies) and the Neil Gehrels Swift Observatory ...Conference Paper -
Relentless multi-wavelength variability of Markarian 421 and Markarian 501
(2022)PoS: Proceedings of Science ~ 37th International Cosmic Ray Conference (ICRC 2021)Mrk 421 and Mrk 501 are two close bright and well-studied high-synchrotron-peaked blazars, which feature bright and persistent GeV and TeV emission. We use the longest and densest dataset of unbiased observations of these two sources, obtained at TeV and GeV energies during 5 years with the FACT telescope and Fermi-LAT. To characterize the variability and derive constraints on the emission mechanism, we augment the dataset with contemporaneous ...Conference Paper -
Statistical properties of flux variations in blazar light curves at GeV and TeV energies
(2022)PoS: Proceedings of Science ~ 37th International Cosmic Ray Conference (ICRC 2021)Despite numerous detections of individual flares, the physical origin of the rapid variability observed from blazars remains uncertain. Using Bayesian blocks and the Eisenstein-Hut HOP algorithm, we characterize flux variations of high significance in the γ-ray light curves of two samples of blazars. Daily binned long-term light curves of TeV-bright blazars observed with the First G-APD Cherenkov Telescope (FACT) are compared to those ...Conference Paper -
FACT - Database-based Analysis and Spectrum Calculations
(2022)PoS: Proceedings of Science ~ 37th International Cosmic Ray Conference (ICRC 2021)The First G-APD Cherenkov Telescope (FACT) is located at the Observatory Roque de los Muchachos on the Canary island La Palma. It uses the imaging air Cherenkov technique to detect gamma rays. With the help of silicon based photosensors in the camera, FACT is an ideal instrument to monitor a small sample of sources with a good time coverage. The automatic operation of the telescope allows an increase of the duty cycle of the instrument. ...Conference Paper -
Multiwavelength variability and correlation studies of Mrk421 during historically low X-ray and γ-ray activity in 2015–2016
(2022)PoS: Proceedings of Science ~ 37th International Cosmic Ray Conference (ICRC 2021)In this work, we report multi-band flux variability and correlations of the nearby (z=0.031) blazar Markarian 421 (Mrk~421) using multi-wavelength (MWL) data from November 2014 to June 2016. In this period, Mrk~421 exhibited historically low activity in X-rays and very-high-energy gamma rays (VHE; E>0.1 TeV) and an additional spectral component was observed by \textit{Swift}-BAT. The highest flux variability occurs in X-rays and VHE which, ...Conference Paper -
FACT - Highlights from more than Eight Years of Unbiased TeV Monitoring
(2022)PoS: Proceedings of Science ~ 37th International Cosmic Ray Conference (ICRC 2021)The First G-APD Cherenkov Telescope (FACT) has been monitoring blazars at TeV energies for more than eight years. Using solid state photo sensors and performing robotic operations results in a maximized duty cycle of the instrument and minimized observational gaps, providing an unprecedented data sample of more than 14700~hours of physics data. With an unbiased observing strategy, a small sample of sources is monitored. Results of an ...Conference Paper -
Extreme blazars under the eyes of MAGIC
(2022)PoS: Proceedings of Science ~ 37th International Cosmic Ray Conference (ICRC 2021)Extreme high-frequency-peaked BL Lac objects (EHBLs) are the most energetic persistent sources in the universe. This contribution reports on long-term observing campaigns of tens of EHBLs that have been organized by the MAGIC collaboration to enlarge their population at VHE and understand the origin of their extreme properties. EHBLs are characterized by a spectral energy distribution (SED) featuring a synchrotron peak energy above 1 keV. ...Conference Paper