Speaker
Description
The existence of the Intergalactic Magnetic Field (IGMF) in the voids of the Large Scale Structure provides a unique opportunity to infer the information about the evolution of the Universe in the early times. Currently, the most promising way to measure this field is through the IGMF-induced halos around the distant, gamma-ray loud AGNs. Among these 1ES 0229+200 remains the most suitable, given its hard GeV spectrum and absence of strong variability on the yearly time scales.
In what follows, we present the results of 4 years of MAGIC observations of 1ES 0229+200, combined with the 9 year of the Fermi/LAT data, aimed to detect the degree-scale IGMF-induced halo around this source in the GeV-TeV energy range. Though no halo is detected, these observations allow us to derive a lower bound on the IGMF strength (in the large correlation length limit) at the level of $10^{-14}$ G - combining both the morphological and spectral information on the halo. We further discuss the implications of this bound for the existing IGMF models.