LAPPDs in ANNIE: A new technology for future neutrino experiments

The ANNIE experiment at Fermilab will be the first experiment testing Large-Area Picosecond Photodetectors (LAPPDs) in a gadolinium-loaded water Cherenkov detector, placed in a neutrino beam with a peak energy of 700 MeV. LAPPDs are a novel technology for photodetection with a high gain, an excellent timing (<100 psec) and a militemeter-level spatial resolution. During the physics phase of ANNIE, that followed the successful measurement of beam-induced backgrounds, the entire water tank (26 tons) will be fully covered with photomultiplier tubes and several functional LAPPDs, thus enabling detailed reconstruction of kinematics. LAPPDs show substantial improvement in precision for vertex reconstruction and they will help to understand the topology of neutrino-nucleus interactions. ANNIE is designed to study the abundance of final state neutrons produced in charged-current interactions and LAPPDs will be critical to achieve this goal. This presentation will give an overview of the experiment, the design and performances of the LAPPDs and the current status of the project.