Using optical lines to study particle acceleration at supernova remnants

摘要: The shocks of several young supernova remnants (SNR) are often associated with very thin optical filaments dominated by Balmer emission resulting from charge-exchange and collisional excitation between neutral Hydrogen the interstellar medium shocked protons electrons. Optical lines a direct probe conditions at shock, in particular width narrow broad components reflect temperature upstream downstream respectively. When shock accelerate efficiently non-thermal particles, structure changes producing anomalous it is possible to use their line shape spatial profile check efficiency SNR accelerating cosmic rays. Here we illustrate kinetic theory acceleration presence neutrals some applications SNRs. We show that three cases (RCW 86, 0509-67.5 Tycho) can be explained assuming fraction $\sim 10\%$ total energy converted into not thermal while one single case, northwestern part SN 1006, there no evidence efficient acceleration.