Young supernova remnants (SNRs), only a few hundred years old, are among the most energetic and dynamic environments in the Galaxy. Their fast shocks (travelling at thousands of km/s) and amplified magnetic fields (0.1–1 G) create ideal conditions for cosmic-ray acceleration. At the same time, high-energy electrons undergo rapid synchrotron cooling, which counteracts acceleration. This balance...
Identifying the accelerators of Galactic cosmic ray (CR) protons with energies up to a few PeV remains a theoretical and observational challenge. Supernova remnants (SNRs) represent strong candidates because they provide sufficient energetics to reproduce the CR flux observed at Earth. Moreover, their strong forward shocks provide an efficient means of accelerating particles: diffusive shock...
Observations have established supernova remnants (SNRs) as efficient accelerators of cosmic rays, in particular electrons. Whereas the acceleration process is known in principle, many aspects are poorly understood. In fact, a number of central points that were considered certain twenty years ago have since had to be discarded. It is still unclear how the soft production spectrum required by...
The idea of supernova remnants (SNRs) as Galactic PeVatrons is increasingly challenged by the lack of observational evidence, with current theory suggesting that only the most energetic SNRs in unusually dense environments can reach PeV energies. We approach this problem in two complementary ways. First, we rely on neutrinos as smoking-gun signatures of hadronic interactions and compile a...
