Production of vector K mesons and their spin alignment in NOMAD

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First measurements of K^\star(892)^\pm mesons production properties and their spin alignment in \nu_\mu charged current (CC) and neutral current (NC) interactions are presented. The analysis of the full data sample of the NOMAD experiment is performed in different kinematic regions. For {K^\star}^+ and {K^\star}^- mesons produced in \nu_\mu CC interactions and decaying into K^0 \pi^\pm we have found the following yields per event: (2.6\pm0.2(\mbox{stat.})\pm0.2(\mbox{syst.}))\% and (1.6\pm0.1(\mbox{stat.})\pm0.1(\mbox{syst.})) respectively, while for the {K^\star}^+ and {K^\star}^- mesons produced in \nu\mbox{NC} interactions the corresponding yields per event are: (2.5\pm0.3(\mbox{stat.})\pm0.3(\mbox{syst.})) and (1.0\pm0.3(\mbox{stat.})\pm0.2(\mbox{syst.})). The results obtained for the \rho_{00} parameter, 0.40\pm0.06(\mbox{stat.})\pm0.03(\mbox{syst.}) and 0.28\pm0.07(\mbox{stat.})\pm0.03(\mbox{syst.}) for K^\star(892)^+ and K^\star(892)^- produced in \nu_\mu CC interactions, are compared to theoretical predictions tuned on LEP measurements in e+e- annihilation at the Z0 pole. For K^\star(892)^+ mesons produced in \nu\mbox{NC} interactions the measured \rho_{00} parameter is 0.66\pm0.10(\mbox{stat.})\pm0.05(\mbox{syst.}).