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arXiv · 0801.4711

Polarized Structure Function $σ_{LT'}$ for $p({\vec e},e'K^+)Λ$ in the Nucleon Resonance Region

Rakhsha Nasseripour·Brian Raue·Daniel Carman·Pawel Ambrozewicz·the CLAS Collaboration
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Abstract

The first measurements of the polarized structure function $σ_{LT'}$ for the reaction $p(\vec e,e'K^+)Λ$ 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. $σ_{LT'}$ 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 $σ_{LT'}$ are comparable in magnitude to previously reported results from CLAS for $σ_{LT}$, the real part of the same response. An intriguing sign change in $σ_{LT'}$ is observed in the high $Q^2$ data at $W\approx 1.9$ GeV. Comparisons to several existing model predictions are shown.

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Rakhsha Nasseripour, Brian Raue, Daniel Carman, Pawel Ambrozewicz, the CLAS Collaboration. 2008-01-30. Polarized Structure Function $σ_{LT'}$ for $p({\vec e},e'K^+)Λ$ in the Nucleon Resonance Region. https://doi.org/10.1103/physrevc.77.065208

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