Effect of Cosmic Rays on the Evolution and Momentum Deposition of Supernova Remnants

Using a semianalytical approach based on the thin-shell approximation, we calculate the long-term evolution of supernova remnants (SNRs) while also accounting for the cosmic rays (CRs) accelerated at their blast waves. Our solution reproduces the results of state-of-the-art fluid simulations across the adiabatic and radiative stages for the gas-only case, and it predicts that typical CR acceleration efficiencies (≈10%) can boost SNR momentum deposition by a factor of 2-3. This enhancement can become as large as an order of magnitude in environments in which the gas experiences more severe radiative losses. This result may have a crucial impact on modeling the effect of supernova feedback on star formation and galaxy evolution.