“Cosmic-Ray Super-PeVatrons and Extreme Accelerators”
The LHAASO experiment is a new large-area, ground-based gamma-ray telescope designed to detect gamma-rays up to ~10^15 eV with unprecedented sensitivity. LHAASO has now unambiguously discovered PeVatrons in the Milky Way. The first Cosmic Ray Super-PeVatron is found in the Cygnus region of the sky, with 8 photons above 1 PeV arriving in a so-called cosmic ray bubble of angular size 10°. LHAASO has also discovered that a couple of PWNe (Pulsar Wind Nebulae) emit photons up to 2 PeV. The discovery of these so-called “Extreme Accelerators” in our galaxy poses significant theoretical challenges for our understanding of particle acceleration and the origin of cosmic rays. To make further progress, we need to improve the spatial resolution of our detectors, and we are planning an upgrade to LHAASO called LACT that makes use of the imaging air Cherenkov technique. The direct detection of neutrinos from PeVatrons, e.g., by ICECUBE-Gen2, would put in the last piece of the big puzzle that has lasted for over a century.
Host: Paolo Coppi