[Deeppwg] Abstract for EINN 2025

[elouan]

Dear all,

I am a PhD student at CEA Saclay, working with Maxime Defurne on the 
extraction of the beam spin asymmetry in the Sullivan process and I am 
planning to submit the following abstract to the EINN 2025 conference, 
which will be held in October. I would like to present preliminary 
results on the Sullivan DVCS beam spin asymmetry measurements with RG-a 
data.

Title : First measurement of the DVCS beam spin asymmetry in the 
Sullivan process

Abstract : Deeply Virtual Compton Scattering (DVCS) is a powerful tool 
to investigate the internal structure of hadrons in terms of Generalized 
Parton Distributions (GPDs). The Sullivan process, involving the 
exchange of a virtual pion from the proton’s meson cloud, offers a 
unique opportunity to access the three-dimensional structure of the pion 
at high energies. Since the pion plays a central role in QCD dynamics, 
being the lightest hadron and the Goldstone boson associated with chiral 
symmetry breaking, unraveling its structure is of fundamental importance 
for our understanding of hadronic matter.
This work aims at measuring, for the first time, the DVCS beam spin 
asymmetry (BSA) in the Sullivan process, using data collected with the 
CLAS12 experiment at Jefferson Lab with a 10.6 GeV electron beam on a 
proton target. These preliminary results demonstrate the feasibility of 
this novel measurement, thereby improving our understanding of the 
Sullivan process and validating this approach as a tool to probe the 
pion’s internal dynamics. This first measurement paves the way for an 
exploration of the pion structure through its GPDs, and sets the stage 
for future studies at Jefferson Lab and at the upcoming Electron-Ion 
Collider.

Please let me know if you have any comments or feedback.

Best regards,

Elouan