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Off-diagonal Helicity Density Matrix Elements for Vector Mesons Produced at LEP

Mauro Anselmino·Marc Bertini·Francesco Murgia·Paulo Quintairos
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Abstract

Final state quark-antiquark interactions may 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 and D^*'s. Predictions are given for rho_{1,-1} of several mesons produced at large z and small p_T, i.e. collinear with the parent jet; the values obtained for phi and D^* are in agreement with data.

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Mauro Anselmino, Marc Bertini, Francesco Murgia, Paulo Quintairos. 1997-04-28. Off-diagonal Helicity Density Matrix Elements for Vector Mesons Produced at LEP. https://doi.org/10.1007/s100520050159

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