Galactic Cosmic rays from Supernova Remnants: II Shock Acceleration of Gas and Dust

We present a quantitative model of galactic cosmic ray (GCR) origin and acceleration, wherein a mixture of interstellar and/or circumstellar gas and dust is accelerated by a supernova remnant (SNR) blast wave. The gas and dust are accelerated simultaneously, but differences in how each component is treated by the shock leaves a distinctive signature which we believe exists in the cosmic ray composition data. A re-examination of the detailed GCR elemental composition, presented in a companion paper, has led us to abandon the long held assumption that GCR abundances are somehow determined by first ionization potential (FIP). Instead, volatility and mass (presumably mass-to-charge ratio) seem to better organize the data: among the volatile elements, the abundance enhancements relative to solar increase with mass (except for the slightly high H/He ratio); the more refractory elements seem systematically overabundant relative to the more volatile ones in a quasi-mass-independent fashion. If this is the case, material locked in grains in the interstellar medium must be accelerated to cosmic ray energies more efficiently than interstellar gas-phase ions. Here we present results from a nonlinear shock model which includes (i) the direct acceleration of interstellar gas-phase ions, (ii) a simplified model for the direct acceleration of weakly charged grains to