Polarized Structure Function $\ddot{I}{ƒ}_{L{T}^{\prime }}$ for $p(\vec{e},e^{\prime }{K}^{+})\hat{I}›$ in the Nucleon Resonance Region

Abstract

The first measurements of the polarized structure function $\ddot{I}{ƒ}_{L{T}^{\prime }}$ for the reaction $p(\vec{e},e^{\prime }{K}^{+})\hat{I}›$ in the nucleon resonance region are reported. Measurements are included from threshold up to $W$=2.05 GeV for central values of $Q^2$ of 0.65 and 1.00 GeV${}^2$, and nearly the entire kaon center-of-mass angular range. $\ddot{I}{ƒ}_{L{T}^{\prime }}$ is the imaginary part of the longitudinal-transverse response and is expected to be sensitive to interferences between competing intermediate s-channel resonances, as well as resonant and non-resonant processes. The results for $\ddot{I}{ƒ}_{L{T}^{\prime }}$ are comparable in magnitude to previously reported results from CLAS for $\ddot{I}{ƒ}_{LT}$, the real part of the same response. An intriguing sign change in $\ddot{I}{ƒ}_{L{T}^{\prime }}$ is observed in the high $Q^2$ data at $W\approx 1.9$ GeV. Comparisons to several existing model predictions are shown.

2 tex files and 12 figures (14 eps files), 33 pages in one column format