A search for deeply-bound kaonic nuclear state at the J-PARC E15 experiment

The J-PARC E15 experiment will be performed to search for the simplest kaonic nuclear bound state, K¯NN, by the in-flight He3(K−,N) reaction. The exclusive measurement will be performed by a simultaneous measurement of the missing mass using the forward neutron or proton, and the invariant mass via the expected decay, e.g. K−pp→Λp→pπ−p. In this report, an overview of the experiment and an analysis of engineering runs performed in February and June are presented.