Convolution of Breit-Wigner with Gaussian

Dear All,

i am a new user in Root & RooFit.

i calculate the differential cross sections as a function of diphoton invariant mass for the higgs decay to two photons (H->gamma gamma). Now i have the values of the differential cross sections against the diphoton invariant masses in the range of 125.6 to 126 GeV (range of invariant mass). The behavior of the diff. cross section distribution takes the form of a Breit Wigner with a very narrow width and a small kink at one side of the tail.

Now i want to convolute this distribution with a Gaussian. i am following the example given in the Roofit manual using the ready made Roofit voigtian macro. In that macro voigtian function is a default function of Roofit and i don’t have any control to feed our calculated differential cross sections values.

Is it possible to feed our data points and then convolute with the Gaussian without using the voigtian function ?

i highly appreciate your any suggestions. Thanks.

With regards,