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zashift: redshift an additive model

This convolution model redshifts an additive model. It takes the calculated model and shifts energies by 1/(1+z) then applies an additional 1/(1+z) factor to the model values.

The energies command must be to used to extend the maximum energy over which the model is being calculated to (1+z) times the maximum energy in the response.

The parameter is:

par1 redshift

An example model use is:

XSPEC>model phabs*zashift*(pow+ga)
which redshifts the power-law and gaussian then multiplies by local absorption.