The Jiangmen Underground Neutrino Observatory (JUNO) is a neutrino medium baseline experiment under construction in southern China, expecting to be completed in 2023. The experiment has been proposed with the main goals of determining the neutrino mass ordering and measuring three oscillation parameters with sub-percent precision. To reach these goals, JUNO is located about 52.5 km from two nuclear power plants and will detect electron antineutrinos from reactors through inverse beta decay. Furthermore, an unprecedented energy resolution of 3% at 1 MeV is required. The JUNO detector consists of 20 kton of liquid scintillator contained in a 35.4 m diameter acrylic vessel, which is instrumented with a system of about 17,612 20-inch Large-PMTs and 25,600 3-inch small-PMTs, with a total photocoverage greater than 75%.
The front-end electronics for the Large-PMT system consists of a Global Central Unit (GCU), which performs the analog-to-digital conversion of the waveforms a few meters away from the PMT, thus providing good performance in terms of signal-to-noise ratio.
The mass production of the Large-PMT electronics was carried out in a dedicated facility in Kunshan, China. At the production site, several tests were performed to assess the integrity and the performances of the GCUs; the integration with the back-end electronics was also tested.
This contribution will focus on the test protocol that has been developed for the mass testing of the Large-PMT electronics at Kunshan. Results of the tests will also be presented.