10-16 June 2018
Dalhousie University
America/Halifax timezone
Welcome to the 2018 CAP Congress Program website! / Bienvenue au siteweb du programme du Congrès de l'ACP 2018!

Exclusive Backward-Angle Meson Electroproduction -- Unique access to $u$-channel physics

12 Jun 2018, 14:15
SUB 224 (cap.50) (Dalhousie University)

SUB 224 (cap.50)

Dalhousie University

Oral (Non-Student) / Orale (non-étudiant(e)) Nuclear Physics / Physique nucléaire (DNP-DPN) T3-5 Hadronic Physics (DNP) | Physique hadronique (DPN)


Garth Huber (University of Regina)


Exclusive meson electroproduction at different squared four-momenta of the exchanged virtual photon, $Q^2$, and at different four-momentum transfers, $t$ and $u$, can be used to probe QCD's transition from hadronic degrees of freedom at long distance scale to quark-gluon degrees of freedom at short distance scale. Backward-angle meson electroproduction was previously ignored, but is anticipated to offer complimentary information to conventional forward-angle meson electroproduction studies on nucleon structure. The results of our pioneering study of backward-angle $\omega$ cross sections through the exclusive $p(e,e'p)\omega$ reaction will be presented. The experiment was performed as part of E01-004 in Jefferson Lab Hall C, with central $Q^2$ values of 1.60 and 2.45 GeV$^2$, and $W$=2.21 GeV. The extracted cross sections were separated into transverse (T), longitudinal (L), and LT, TT interference terms. The data set has a unique coverage of $u\sim$ 0, opening up a new means to study the transition of the nucleon wave function through backward-angle experimental observables. Plans to extend these studies to the $\pi^0$ and $\phi$ channels will also be presented.

Primary authors

Garth Huber (University of Regina) Wenliang (Bill) Li (University of Regina and College of William and Mary)

Presentation Materials