The effect of nonlinear terms on the gluon distribution function and its Mellin moments in small-x region

Document Type : Full length research Paper

Authors

Faculty of Physics- Shahid Bahonar University of Kerman- Kerman- Iran

Abstract

We investigate Q^2 evolution of gluon distribution function in small-x region. In general, the evolution of parton distribution functions of hadrons is given by linear DGLAP evolution equations. In small-x region the gluon density increases. So in order to consider the effect of gluon recombination in this region, some corrections as nonlinear terms are added to DGLAP equations. This modified equation is known as GLR-MQ evolution equation. In this work, the GLR-MQ equation for gluon distribution of proton is solved and the obtained results compared with those of DGLAP evolution equation. We also calculate the first and second order Mellin moments of this distribution. The obtained results show important effect of nonlinear corrections on the evolution of gluon distribution function.

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Main Subjects


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