par Besnard, Philippe;Roosen, R.;Van Mechelen, Pierre;Clerbaux, Barbara 
;Collard, Caroline ;de Wolf, Els;Favart, Laurent ;Heremans, R.;Janssen, Xavier ;Johnson, Denis;Marage, Pierre ; [et al.]
Référence Physics letters. Section B, 483, 4, page (360-372)
Publication Publié, 2000-06
;Collard, Caroline ;de Wolf, Els;Favart, Laurent ;Heremans, R.;Janssen, Xavier ;Johnson, Denis;Marage, Pierre ; [et al.]Référence Physics letters. Section B, 483, 4, page (360-372)
Publication Publié, 2000-06
Article révisé par les pairs
| Résumé : | The elastic electroproduction of φ mesons is studied at HERA with the H1 detector for photon virtualities 1 < Q2 < 15 GeV2 and hadronic centre of mass energies 40 < W < 130 GeV. The Q2 and t dependences of the cross section are extracted (t being the square of the four-momentum transfer to the target proton). When plotted as function of (Q2 + M(v)/2) and scaled by the appropriate SU(5) quark charge factor, the φ meson cross section agrees within errors with the cross sections of the vector mesons V = p, ω and J/ψ. A detailed analysis is performed of the φ meson polarisation state and the ratio of the production cross sections for longitudinally and transversely polarised φ mesons is determined. A small but significant violation of s-channel helicity conservation (SCHC) is observed. (C) 2000 Elsevier Science B.V. |
