Study of the elementary reactions to search for the bound state via the He reaction at J-PARC

山我 拓巳*; 谷田 聖; 他74名*

AIP Conference Proceedings 1735, p.040007_1 - 040007_6, 2016/05

https://doi.org/10.1063/1.4949411

We have searched for the simplest kaonic nuclear state, , using the in-flight He reaction at the J-PARC hadron experimental facility. In the semi-inclusive neutron missing-mass spectrum at , an excess of yield was observed just below the mass-threshold, which cannot be explained by any elementary reactions [PTEP 2015, 061D01]. To understand the missing-mass spectrum of He, we investigated the elementary reactions using hydrogen and deuterium targets. The missing-mass spectrum was well described by the charge-exchange reaction. However, in the spectrum, we observed an excess of yield just below the mass-threshold, which was similar to that in the He spectrum.