Mass Production of Large-sized Nuclear Emulsion Plates for J-PARC E07

In the E07 experiment at J-PARC, we systematically study double strangeness (S = -2) systems on Λ-Λ and Ξ-N interaction via S = -2 nuclei such as double Λ hypernuclei and twin Λ hypernuclei with hybrid-emulsion method. The number of S = -2 nuclei is planned to be about 10 which is 10 times or more events than that of the E373 experiment at KEK-PS. We have to prepare for large-scale emulsion plates by huge amount of emulsion gel with weight of 2.1 t, which is about 3 times’ quantity used for E373. To make it possible, we have developed methods for treatment of supporting films and for making emulsion plates. We have successfully produced 1500 plates.