QED corrections to the evolution of parton distributions
نویسندگان
چکیده
We study the systematic inclusion of QED corrections in the evolution of parton distributions. O(α) corrections modify the evolution equation for parton distributions. They introduce additional parton distributions, like the photon distribution in the nucleon, and lead to additional mixing effects. We discuss the modifications for a realistic model of Nf,up up-type flavours and Nf,down down-type flavours. We have implemented these corrections into a numerical program and we quantify the size of these effects in a toy model. The corrections reach the order of 1%.
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تاریخ انتشار 2004