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arXiv · hep-ph/9904205

Off-diagonal helicity density matrix elements for vector mesons produced in polarized e+e- processes

M. Anselmino·M. Bertini·F. Caruso·F. Murgia·P. Quintairos
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Abstract

Final state quark-antiquark interactions give origin to non zero values of the off-diagonal element rho_{1,-1} of the helicity density matrix of vector mesons produced in e+e- annihilations, as confirmed by recent OPAL data on Phi, D^* and K^*'s. New predictions are given for rho_{1,-1} of several mesons produced at large x_E and small p_T -- i.e. collinear with the parent jet -- in the annihilation of polarized e+ and e-; the results depend strongly on the elementary dynamics and allow further non trivial tests of the Standard Model.

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M. Anselmino, M. Bertini, F. Caruso, F. Murgia, P. Quintairos. 1999-04-01. Off-diagonal helicity density matrix elements for vector mesons produced in polarized e+e- processes. https://doi.org/10.1007/s100520050652

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