Measurement of the Polarized Structure Function $\ddot{I}{ƒ}_{L{T}^{\prime }}$ for $p(\vec{e},e^{\prime }p)\ddot{I}{€}^o$ in the $\hat{I}”(1232)$ Resonance Region

Abstract

The polarized longitudinal-transverse structure function $\ddot{I}{ƒ}_{L{T}^{\prime }}$ has been measured in the $\hat{I}”(1232)$ resonance region at $Q^2=0.40$ and 0.65 GeV${}^2$. Data for the $p(\vec{e},e^{\prime }p)\ddot{I}{€}^o$ reaction were taken at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. For the first time a complete angular distribution was measured, permitting the separation of different non-resonant amplitudes using a partial wave analysis. Comparison with previous beam asymmetry measurements at MAMI indicate a deviation from the predicted $Q^2$ dependence of $\ddot{I}{ƒ}_{L{T}^{\prime }}$ using recent phenomenological models.

5 pages, LaTex, 4 eps figures: to be published in PRC/Rapid Communications. Version 2 has revised Q^2 analysis