Direct Observational Constraint on Upstream Magnetic Field Amplification Reveals the Particle Acceleration Limit in a Supernova Remnant

Yuya Kawabata, Takaaki Tanaka, Hiromasa Suzuki +1

The origin of Galactic cosmic rays up to the knee energy (PeV) remains a long-standing open question in astrophysics. Supernova remnant shocks are leading candidates for accelerati…