Higher - twist contributions to the Structure Functions coming from 4 - fermion operators ∗
نویسندگان
چکیده
We evaluate the contribution of a class of higher–twist operators to the lowest moment of the Structure Functions , by computing appropriate matrix elements of six four–fermion operators in the quenched approximation. Their perturbative renormalization constants and mixing coefficients are calculated in the 't Hooft–Veltman scheme of dimensional regularization, using codes written in the algebraic manipulation computer language FORM.
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