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Exclusive electroproduction of phi mesons at 4.2 GeV

CLAS Collaboration·K. Lukashin·E. S. Smith
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Abstract

We studied the exclusive reaction e p --> e' p' phi using the phi --> K^+ K^- decay mode. The data were collected using a 4.2 GeV incident electron beam and the CLAS detector at Jefferson Lab. Our experiment covers the range in Q^2 from 0.7 to 2.2 GeV^2, and W from 2.0 to 2.6 GeV. Taken together with all previous data, we find a consistent picture of phi production on the proton. Our measurement shows the expected decrease of the t-slope with the vector meson formation time c Delta tau below 2 fm. At = 0.6 fm, we measure b_phi = 2.27 +- 0.42 GeV^-2. The cross section dependence on W as W^{0.2+-0.1} at Q^2 = 1.3 GeV^2 was determined by comparison with phi production at HERA after correcting for threshold effects. This is the same dependence as observed in photoproduction.

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CLAS Collaboration, K. Lukashin, E. S. Smith. 2001-04-10. Exclusive electroproduction of phi mesons at 4.2 GeV. https://doi.org/10.1103/physrevc.63.065205

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