[Deeppwg] [EXTERNAL] Abstract on SIDIS proton BSA for QCD Evolution and Transversity workshop

[Marco Contalbrigo]

Dear all,
below is the abstract about SIDIS proton BSA results Fatiha 
intends to submit to the QCD Evolution and Transversity
workshops. The presentation will be based on already approved
results and previous presentations at CPHI and APS.

Possible comments and suggestions are welcome.
Best regards, Marco. 

Multi-Dimensional studies of the ep->e'p'+X Single Spin Asymmetries

Authors:Fatiha Benmokhtar, Harut Avakian and  Timothy Hayward

Studies of the properties and the azimuthal distribution of hadrons produced in the Target Fragmentation Region serve as a test of our
complete understanding of the different mechanisms in the SIDIS production of hadrons and provide additional information on the QCD
dynamics that are not accessible with single hadron production in the Current Fragmentation Region. We present first Multi-dimensional
studies of beam SSA for semi-inclusive protons (ep ? e?p'+X), produced in the TFR, that can be related to higher twist Fracture Functions
describing the F_LU structure function. Such measurements were performed with the CLAS12 detector in Hall B at Jefferson lab using a
longitudinally polarized 10.6~GeV electron beam on an unpolarized hydrogen target. Preliminary results of this study captured the
transition between the TFR and CFR regions showing a clear sign change of the SSA for protons produced in the backward region in CM,
dominated by TFR protons providing a criteria for experimental separation of CFR and TFR regions. These findings are opening a new avenue
for studies of nucleon structure.