First Measurement of the Polarization Observable E in the $\vec{p}(\vec{\gamma },{\pi }^{+})n$ Reaction up to 2.25 GeV

S. Strauch, W. J. Briscoe, M. Döring +165

First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction $\vec{\gamma }\vec{p}\to {\pi }^{+}n$, has…