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Measurement of elastic electroproduction of phi mesons at HERA

H1 Collaboration·C. Adloff
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Abstract

The elastic electroproduction of phi mesons is studied at HERA with the H1 detector for photon virtualities 1 < Q^2 < 15 GeV^2 and hadronic centre of mass energies 40 < W < 130 GeV. The Q^2 and t dependences of the cross section are extracted (t being the square of the four-momentum transfer to the target proton). When plotted as function of (Q^2 + M_V^2) and scaled by the appropriate SU(5) quark charge factor, the phi meson cross section agrees within errors with the cross sections of the vector mesons V = rho, omega and J/psi. A detailed analysis is performed of the phi meson polarisation state and the ratio of the production cross sections for longitudinally and transversely polarised phi mesons is determined. A small but significant violation of s-channel helicity conservation (SCHC) is observed.

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H1 Collaboration, C. Adloff. 2000-05-05. Measurement of elastic electroproduction of phi mesons at HERA. https://doi.org/10.1016/s0370-2693(00)00613-4

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