Limits on diffusive shock acceleration in dense and incompletely ionised media
نویسندگان
چکیده
The limits imposed on diffusive shock acceleration by upstream ion-neutral Alfvén wave damping, and by ionisa-tion and Coulomb losses of low energy particles, are calculated. Analytic solutions are given for the steady upstream wave ex-citation problem with ion-neutral damping and the resulting escaping upstream flux calculated. The time dependent problem is discussed and numerical solutions presented. Finally the significance of these results for possible observational tests of shock acceleration in supernova remnants is discussed.
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