highecut, zhighect: high-energy cutoff

A high energy cutoff.

$$M(E) = \begin{array}{ll} exp\left[(E_c-E)/E_f\right] & E \geq E_c\\ [.2cm] 1.0 & E \leq E_c \end{array}$$

where

par1=$E_c$	cutoff energy in keV
par2=$E_f$	e-folding energy in keV

The redshifted version zhighect has

$$M(E) = \begin{array}{ll} exp\left[(E_c-E[1+z])/E_f\right] & E \geq E_c\\ [.2cm] 1.0 & E \leq E_c \end{array}$$

where

par1=$E_c$	cutoff energy in keV
par2=$E_f$	e-folding energy in keV
par3=z	redshift