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            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, S.P., ApJ 493, 357 1998. This is a  highly specific, detailed model for a fairly narrow set of conditions. See also Reynolds, S.P., ApJL 459, L13 1996. Note that the radio spectral  index and flux can be obtained from Green's Catalogue at   http://www.mrao.cam.ac.uk/surveys/snrs 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 Em3 in a magnetic field of 4B1, in the notation of Reynolds (1998), Eq. (19).

norm

1 GHz flux (Jy)