Description of the CLAS 2018 unpolarized cross-section data

Determine how to describe the CLAS 2018 unpolarized DVCS cross-section data within a local extraction and global fit without introducing bias, including the origin of their points lying below the Bethe–Heitler baseline at \(\phi\sim\pi\).

Background

Most of the CLAS 2018 unpolarized cross-section data were excluded because their inclusion biased the extraction. The authors report that neither the global analysis nor a local extraction can currently reproduce these measurements, particularly in kinematic bins where very small-uncertainty points fall below the Bethe–Heitler baseline. Resolving this discrepancy is necessary before the data can be reliably incorporated into future DVCS amplitude extractions.