The Reliable Determination of $F_\pi$ beyond $Q^2$=6 GeV$^2$

ORAL

Abstract

The charged pion form factor, $F_{\pi}(Q^2)$, is an important quantity which can be used to advance our knowledge of hadronic structure. However, the extraction of $F_{\pi}$ from electroproduction data requires a model of the $^1$H$(e,e^{\prime}\pi^+)n$ reaction, and thus is inherently model dependent. Furthermore, one is either $(a)$ limited to the kinematic regime where the pion pole term dominates the longitudinal cross section ($-t_{min}<$0.20 GeV$^2$), or $(b)$ required to have some other reliable means to identify the non-pole backgrounds expected to dominate at higher $-t$. The E12-06-101 pion form factor experiment planned to run at Jefferson Lab Hall C in a few years respects constraint $(a)$, and is expected to provide reliable $F_{\pi}$ values of unprecedented quality up to $Q^2$=6 GeV$^2$. Measurements using the same Jefferson Lab apparatus above $Q^2>$8 GeV$^2$ are possible, provided one has a means to address constraint $(b)$. I will discuss some of the issues involved if one is to make these measurements a successful reality.

Authors

  • Garth Huber

    Univ of Regina