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First Measurement of Transferred Polarization in the Exclusive e p --> e' K+ Lambda Reaction

CLAS Collaboration·D. S. Carman
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Abstract

The first measurements of the transferred polarization for the exclusive ep --> e'K+ Lambda reaction have been performed in Hall B at the Thomas Jefferson National Accelerator Facility using the CLAS spectrometer. A 2.567 GeV electron beam was used to measure the hyperon polarization over a range of Q2 from 0.3 to 1.5 (GeV/c)2, W from 1.6 to 2.15 GeV, and over the full center-of-mass angular range of the K+ meson. Comparison with predictions of hadrodynamic models indicates strong sensitivity to the underlying resonance contributions. A non-relativistic quark model interpretation of our data suggests that the s-sbar quark pair is produced with spins predominantly anti-aligned. Implications for the validity of the widely used 3P0 quark-pair creation operator are discussed.

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CLAS Collaboration, D. S. Carman. 2002-12-06. First Measurement of Transferred Polarization in the Exclusive e p --> e' K+ Lambda Reaction. https://doi.org/10.1103/physrevlett.90.131804

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