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تسجيل مستخدم جديدDetermination of the Collins-Soper Kernel from Lattice QCD
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We present lattice results for the non-perturbative Collins-Soper (CS) kernel, which describes the energy-dependence of transverse momentum-dependent parton distributions (TMDs). The CS kernel is extracted from the ratios of first Mellin moments of quasi-TMDs evaluated at different nucleon momenta.The analysis is done with dynamical $N_f=2+1$ clover fermions for the CLS ensemble H101 ($a=0.0854,mathrm{fm}$, $m_{pi}=m_K=422,mathrm{MeV}$). The computed CS kernel is in good agreement with experimental extractions and previous lattice studies.
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The Collins-Soper kernel relates transverse momentum-dependent parton distribution functions (TMDPDFs) at different energy scales. For small parton transverse momentum $q_Tsim Lambda_text{QCD}$, this kernel is non-perturbative and can only be determi
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The Collins-Soper kernel, which governs the energy evolution of transverse-momentum dependent parton distribution functions (TMDPDFs), is required to accurately predict Drell-Yan like processes at small transverse momentum, and is a key ingredient fo
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