2025/02/11 by Oliveros, Sarira Sahu A. U. Puga, Páez-Sánchez, D. I., Sánchez-Colón, G. +5
#FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #High Energy Physics - Phenomenology (hep-ph)
paper · doi:10.48550/arxiv.2502.07940
Markarian 501, a well known high energy BL Lac object, has exhibited several epochs of very high energy (VHE) gamma-ray flaring events when its synchrotron peak frequency shifted above 1017 Hz, a signature of extreme behavior. From July 16 to July 31, 2014 such flaring events were observed for 15 days by various telescopes. On July 19 (MJD 56857.98), the X-ray outburst from the source was at its highest and on the same day an intriguing narrow peak-like feature around 3 TeV was observed by MAGIC telescopes, a feature inconsistent with standard interpretations. Using the well known two-zone photohadronic model, we study these VHE gamma-ray spectra on a day-by-day basis and offer explanation. Our two-zone photohadronic scenario shows that, on MJD 56857.98, the peak-like feature appears at a cutoff energy of Ecγ = 3.18 TeV. Below this energy the observed VHE spectrum increases slowly and above Ecγ it falls faster, thus resulting in a mild peak-like feature.