Off-diagonal helicity density matrix elements for heavy vector mesons   inclusively produced in N-N, gamma-N, l-N interactions
  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 V produced in current jets, with a large energy fraction x_E; the value of rho_(1,-1)(V) is related to the hard constituent dynamics and tests unusual properties of it. Some recent data on phi, K^* and D^* produced in e^+ e^- annihilations at LEP show such effects. Predictions are given here for rho_(1,-1) of heavy mesons produced in nucleon-nucleon, gamma-nucleon and lepton-nucleon interactions. 
M. Anselmino (1), M. Bertini (1 and 2), F. Murgia (3) and B. Pire (4)   ((1) University and INFN, Torino, Italy, (2) IPN, Ly...