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تسجيل مستخدم جديدTMDs, universality and factorization
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We present a short overview on transverse momentum dependent parton distribution and fragmentation functions, giving their partonic interpretation and ways to access them. We then discuss the issue of their universality and its connection to factorization in perturbative QCD.
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I discuss how the rapidity evolution of gluon transverse momentum dependent distribution changes from nonlinear evolution at small $xll 1$ to linear evolution at moderate $xsim 1$.
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