Abstract
We report the first extraction of the pion-nucleon multipoles near the production threshold for the channel at relatively high momentum transfer ( up to 4.2 ). The dominance of the -wave transverse multipole (), expected in this region, allowed us to access the generalized form factor within the light-cone sum-rule (LCSR) framework as well as the axial form factor . The data analyzed in this work were collected by the nearly CEBAF Large Acceptance Spectrometer (CLAS) using a 5.754-GeV electron beam on a proton target. The differential cross section and the - multipole were measured using two different methods, the LCSR and a direct multipole fit. The results from the two methods are found to be consistent and almost independent.
15 More- Received 4 January 2012
DOI:https://doi.org/10.1103/PhysRevC.85.035208
©2012 American Physical Society