Search for: All records

A bstract We study all the possible spin asymmetries that can arise in back-to-back electron-jet production, ep → e + jet + X , as well as the associated jet fragmentation process, ep → e +jet( h )+ X , in electron-proton collisions. We derive the factorization formalism for these spin asymmetries and perform the corresponding phenomenology for the kinematics relevant to the future electron ion collider. In the case of unpolarized electron-proton scattering, we also give predictions for azimuthal asymmetries for the HERA experiment. This demonstrates that electron-jet production is an outstanding process for probing unpolarized and polarized transverse momentum dependent parton distribution functions and fragmentation functions. 

A bstract We derive the transverse momentum dependent (TMD) factorization and resummation formula of the unpolarized transverse momentum distribution ( j T ) for the single hadron production with the thrust axis in an electron-positron collision. Two different kinematic regions are considered, including small transverse momentum limit j T « Q , and joint transverse momentum and threshold limit j T « Q (1 − z h ) « Q , where Q and z h are the hard scattering energy and the observed hadron momentum fraction. Using effective theory methods, we resum logarithms ln( Q/j T ) and ln(1 − z h ) to all orders. In the end, we present the differential cross sections and Gaussian widths calculated for the inclusive charged pion production and find that our results are consistent with the measurements reported by the Belle collaboration.