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arXiv · hep-ph/9810226

Quark fragmentation and off-diagonal helicity density matrix elements for vector meson production

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

As confirmed by some recent LEP data on phi, K^* and D^*0 production, final state interactions in quark fragmentation 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: we give estimates for rho_{1,-1} of vector mesons with a large x_E and collinear with the parent jet, relating its size and sign to the associated hard constituent dynamics. We mention possible non-zero values of rho_{1,-1} in several other processes.

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M. Anselmino, M. Bertini, F. Murgia, P. Quintairos. 1998-10-02. Quark fragmentation and off-diagonal helicity density matrix elements for vector meson production. https://arxiv.org/abs/hep-ph/9810226

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