next up previous contents
Next: gabs: gaussian absorption line Up: Multiplicative Model Components Previous: expabs: exponential roll-off at


expfac: exponential modification

An exponential modification of a spectrum.


\begin{displaymath}
M(E) = \begin{array}{ll}
1+Aexp(-fE) & E > E_c\\ [.2cm]
1 & E < E_c
\end{array}\end{displaymath}

where:

par1=$A$ amplitude of effect
par2=$f$ exponential factor
par3=$E_c$ start energy of modification