sresc: synchrotron spectrum, cut off by particle escape

The synchrotron spectrum from an electron distribution limited by particle escape above some energy. The electrons are shock-accelerated in a Sedov blast wave encountering a constant-density medium containing a uniform magnetic field. The model includes variations in electron acceleration efficiency with shock obliquity, and post-shock radiative and adiabatic losses, as described in Reynolds (1998). This is a highly specific, detailed model for a fairly narrow set of conditions. See also Reynolds (1996). Note that the radio spectral index and flux can be obtained from Green's Catalogue for galactic SNRS.

par1 alpha: radio spectral index (flux proportional to frequency f$^{-\alpha})$
par2 break Hz: approximately the frequency at which the flux has dropped by a factor of 6 below a straight power law extrapolation from radio frequencies. This frequency is 5.3 times the peak frequency radiated by electrons with energy $E_{m3}$ in a magnetic field of $4B_1$, in the notation of Reynolds (1998), Eq. (19).
norm 1 GHz flux (Jy)