Search

The coherent production of 3π systems by charged current antineutrino interactions on neon nuclei is studied in the bubble chamber BEBC exposed to the CERN SPS wide band beam. The coherent signal is attributed mainly to (ρπ) production, where the (ρπ) system is either non-resonant or comes from the decay of a1 mesons. The kinematical variables and the total cross section are compared with the predictions of the meson dominance model. © 1991 Springer-Verlag.

Backward proton and pion production is studied in ν and {Mathematical expression} charged current interactions in neon. The results are compared with other experiments and theory. The complete backward proton data is compatible with protons produced by reinteractions in the nucleus. However in events with only one proton, muon variables appear correlated to those for the backward proton, as expected by the two-nucleon correlation model. © 1989 Springer-Verlag.

The average multiplicities of charged hadrons and of π+, π− and π0 mesons, produced in\(\bar v\)Ne and νNe charged current interactions in the forward and backward hemispheres of theW±-nucleon center of mass system, are studied with data from BEBC. The dependence of the multiplicities on the hadronic mass (W) and on the laboratory rapidity (yLab) and the energy fraction (z) of the pion is also investigated. Special care is taken to determine the π0 multiplicity accurately. The ratio of average π multiplicities\(\frac{{2\left\langle {n_{\pi ^O } } \right\rangle }}{{[\left\langle {n_{\pi ^ + } } \right\rangle + \left\langle {n_{\pi ^ - } } \right\rangle ]}}\) is consistent with 1. In the backward hemisphere\(\left\langle {n_{\pi ^O } } \right\rangle \) is positively correlated with the charged multiplicity. This correlation, as well as differences in multiplicities between\(\mathop v\limits^{( - )} \) and\(\mathop v\limits^{( - )} \),\(\mathop v\limits^{( - )} \) scattering, is attributed to reinteractions inside the neon nucleus of the hadrons produced in the initial\(\mathop v\limits^{( - )} \) interaction.