2018 Impact factor 4.843
Particles and Fields
Eur. Phys. J. C 2, 539-544
DOI 10.1007/s100529800709

Off-diagonal helicity density matrix elements for vector mesons produced at LEP

M. Anselmino1 - M. Bertini1,2 - F. Murgia3 - P. Quintairos1,4

1 Dipartimento di Fisica Teorica, Università di Torino and INFN, Sezione di Torino, Via P. Giuria 1, I-10125 Torino, Italy
2 Institut de Physique Nucléaire de Lyon 43 Bvd. du 11 Novembre 1918, F-69622 Villeurbanne Cedex
3 INFN, Sezione di Cagliari, Via A. Negri 18, I-09127 Cagliari, Italy
4 Centro Brasileiro de Pesquisas Físicas R. Dr. Xavier Sigaud 150, 22290-180, Rio de Janeiro, Brazil

Received: 15 May 1997 / Published online: 20 February 1998

Abstract
Final state $q\bar q$ 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 pT, i.e. collinear with the parent jet; the values obtained for $\phi$ and D* are in agreement with data.


Copyright Springer-Verlag