First Measurement of Transferred Polarization in the Exclusive e p --> e' K+ Lambda Reaction
The first measurements of the transferred polarization for the exclusive {rvec e}p {yields} e{prime}K{sup +}{rvec {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 Q{sup 2} from 0.3 to 1.5 (GeV/c){sup 2}, W from 1.6 to 2.15 GeV, and over the full center-of-mass angular range of the K{sup +} 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{bar s} quark pair is produced with spins predominantly anti-aligned. Implications for the validity of the widely used {sup 3}P{sub o} quark-pair creation operator are discussed.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE; USDOE Office of Energy Research (ER) (US)
- DOE Contract Number:
- AC05-84ER40150
- OSTI ID:
- 837303
- Report Number(s):
- JLAB-PHY-02-137; DOE/ER/40150-3182; hep-ex/0212014; PRLTAO; TRN: US0500971
- Journal Information:
- Physical Review Letters, Vol. 90; Other Information: PBD: 4 Apr 2003; ISSN 0031-9007
- Country of Publication:
- United States
- Language:
- English
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