Presentation #202.04 in the session “Peta-electronvolt Cosmic Accelerators in the Milky Way”.
Current-generation Imaging atmospheric Cherenkov telescopes (IACTs), including H.E.S.S., MAGIC, and VERITAS, provide key capabilities in the quest to identify and characterize Galactic Pevatrons. They span an energy range from below 100 GeV (overlapping Fermi-LAT) to several 10s TeV or higher (overlapping HAWC, LHAASO, and Tibet AS Gamma). However, the key strengths of IACTs lie in their excellent angular resolution, typically better than 0.1 degrees above 1 TeV (and as good as 0.05 deg) and their excellent energy resolution of 15-20% over a broad energy range. While current-generation IACTs generally don’t directly access information about PeV cosmic rays, their abilities to discern morphological and spectral features provide crucial information for characterizing the emission from PeVatrons, such as in the H.E.S.S. observations of diffuse emission near the Galactic Center region, and in connecting the acceleration and emission sites to objects seen at longer wavelengths. In the coming years, the Cherenkov Telescope Array Observatory (CTAO), designed to have an order of magnitude better sensitivity, greater energy reach (from 30 GeV to >100 TeV), and better angular and energy resolutions, will provide a high-resolution survey of the Galactic plane and deep follow-up studies of candidate PeVatrons. In this talk, we review recent observations of potential PeVatrons by current-generation instruments and their near-term prospects, as well as the potential for CTAO to contribute to this science in the coming decade.