Undergraduate Research at Jefferson Lab

Hadron Mass Corrections in Polarized Semi-Inclusive Deep Inelastic Scattering

Student: Steven Casper

School: Carnegie Mellon University

Mentored By: Wally Melnitchouk

We derive mass corrections for semi-inclusive deep inelastic scattering of leptons from nucleons using a collinear factorization framework which incorporates the initial state mass of the target nucleon and the final state mass of the produced hadron. The formalism is constructed specifically to ensure that physical kinematic thresholds for the semi-inclusive process are explicitly respected. We calculate a leading-order cross section from the contraction of a lepton tensor and a hadron tensor, and we find it is a function of mass-dependent scaling variables. Comparison with the cross section without mass corrections shows significant deviation in the kinematic regions of facilities such as Jefferson Lab. The mass corrections will be important to efforts at extracting polarized parton distribution functions from semi-inclusive processes at intermediate energies.