Studies of the Proton Fragmentations

In Hall B of the Thomas Jefferson National Accelerator Facility Accelerator facility, JLab, in Newport News, VA, and using the CLAS12 detection capabilities, a liquid hydrogen target undergoes the SIDIS process with a 10.6 GeV polarized electron beam. Beam Single-spin asymmetries (SSA) for for the ep → e′p'+X channel, also known as ALU, are extracted as a function of different kinematic variables. Experimental setup, data processing and data analysis methods will be explained and our corrections to the physics asymmetries will be presented. This study allows us a clear separation of SIDIS proton resulting from Target fragmentations region from these resulting from the current fragmentation. For the first time a soft intermediate region is observed. This is a benchmark to future SIDIS experiments that try to understand the mechanism and origin of the formation of different hadron species.