Pion Form Factor: Present and Future

The pion charge form factor, $F_{\pi}$, is of key interest in the study of the quark-gluon structure of hadrons. The valence structure of the pion $\langle q\bar{q}\rangle$ is relatively simple, so it is used as a test case for all models of hadronic structure. Experimentally, the measurement of the pion form factor poses special challenges. The technique utilizes a precision Rosenbluth separation of the $p(e,e'\pi^+)n$ reaction at low $-t$. $F_{\pi}$ is then extracted from the separated $\sigma_L$ cross sections with the aid of a model. Over the past several years, we have mounted two experiments at Jefferson Lab (JLab) to measure $F_{\pi}$ over the range of $Q^2=0.6$ to 2.45 GeV$^2$. These measurements are planned to be extended to higher $Q^2$ with the completion of the JLab 12 GeV upgrade. These data would challenge QCD-based calculations in the most rigorous manner. The recent JLab data will be presented and compared to a variety of model calculations, and the future outlook will be discussed.