Coherent production of single pions and rho mesons in charged-current interactions of neutrinos and antineutrinos on neon nuclei at the Fermilab Tevatron.

Abstract

The coherent production of [pi] and [rho] mesons in [nu][sub [mu]]([bar [nu]][sub [mu]])--neon charged-current interactions has been studied using the Fermilab 15-foot bubble chamber filled with a heavy Ne-H[sub 2] mix and exposed to the Teva- tron quadrupole triplet (anti)neutrino beam. The [nu][sub [mu]] ([bar [nu]][sub [mu]]) beam had an average energy of 80 GeV (70 GeV). From a sample corresponding to approximately 28 000 charged-current interactions, net signals of (53[plus minus]9) [mu][sup [plus minus]][pi][sup [minus plus]] coherent events and (19[plus minus]7) [mu][sup [plus minus]][pi][sup [minus plus]][pi][sup 0] coherent events are extracted. For [ital E][gt]10 GeV, the coherent pion production cross section is determined to be (3.2[plus minus]0.7)[times]10[sup [minus]38] cm[sup 2] per neon nucleus whereas the coherent [rho] production cross section is (2.1[plus minus]0.8)[times]10[sup [minus]38] cm[sup 2] per neon nucleus. These cross sections and the kinematical characteristics of the coherent events at [vert bar][ital t][vert bar][lt]0.1 GeV[sup 2] are found to be in general agreement with the predictions of a model based on the hadron dominance and, in the pion case, on the partially conserved axial-vector current hypothesis. Also discussed is the coherent production of systems consisting of three pions.