Exclusive π⁻ Electroproduction off the Neutron in Deuterium in the Resonance Region

Department of Physics and Astronomy, University of South Carolina, Columbia, SC, USA

^a e-mail: tianye8001@gmail.com
^b e-mail: gothe@sc.edu

Published online: 25 March 2016

Abstract

The goal of our research is to provide the exclusive γ^*(n) → p⁺π⁻ reaction cross section from deuterium data using the correction factor that account for the final state re-scattering that can be determined from the data set itself. The “e1e” Jefferson Lab CLAS data set that we analyze includes both a hydrogen and deuterium target run period, which allows a combined analysis of pion electroproduction off the free proton, the bound proton, and the bound neutron under the same experimental conditions. Hence it will provide the experimentally best possible information about the off-shell and final state interaction effects in deuterium, which must be considered in order to extract the neutron information. This data set will provide results with a kinematic coverage for the hadronic invariant mass W up to 1.7 GeV and in the momentum transfer Q² range of 0.4 − 1.0 GeV/c². The cross section analysis of this data set is currently underway, which will considerably improve our knowledge of the Q² evolution of π⁻p electroproduction cross sections off bound neutron needed for the extraction of excited neutron state electrocouplings for the first time.