Measurement of K*(892)0 and K0 mesons in Al + Al collisions at 1.9A GeV

A new measurement of subthreshold K*(892) 0 and K 0 production is presented. The experimental data complete the measurement of strange particles produced in Al + Al collisions at 1.9A GeV measured with the FOPI detector at SIS at GSI (Darmstadt). The K*(892) 0 /K 0 yield ratio is found to be 0.0315 ± 0.006(stat.) ± 0.012(syst.) and is in good agreement with the transport model prediction. These measurements provide information on the in-medium cross section of K + -π - fusion, which is the dominant process in subthreshold K*(892) 0 production.