... CompHEP also The analytical answers for squared diagrams can be obtained in the form of REDUCE or MATHEMATICA code. ... CMS energy squared . ... To make contact with experimental results we must next calculate the invariant differential cross section which we get by applying the formula . ... The formula for the total cross section of Compton scattering can be obtained by integration (1) over t from t min =2Me 2 to t max =Me 4 /s. As above we use MATHEMATICA The result of evaluation is . ...