Manufacture Details of a SWGO Double-Layer Tank Design - Water Cherenkov Detector Prototype

Water-Cherenkov detectors (WCD) have been manufactured in Australia by the company AQUAMATE as part of the RD activities for SWGO. They consist of a steel tank frame with a bladder on its interior satisfying the SWGO double-layer tank design. Tanks and bladders have been custom designed to optimally accommodate the bladder inside the tank and with minimal material usage. They are delivered in compact boxes that are easy to transport. These boxes are designed to fit 24 tanks in a 20-foot container. The double-layer tank design has introduced new features to improve the discrimination between gamma-rays and cosmic rays. Some of these features created challenges for the manufacturing. Some units have been delivered to one of Peru’s candidate sites at 4800 m and to Mexico (the HAWC Observatory, 4100 m) for prototype tests in real conditions. In this contribution we will describe manufacturing and construction details of the first SWGO prototype WCD. These details were envisaged to facilitate: the transport of the units, the assembly, the deployment and maintenance activities of the detectors. Furthermore, the units need to be resistant to strong winds, rain, snow and earthquakes.The costs are scalable with the detector volume. This information could be of interest to other Observatories that are in RD phase, such as the Global Cosmic Ray Observatory (GCOS) for the study of the highest-energy particles in the Universe and the Tau Air Shower Mountain-Based Observatory (TAMBO) for the search of PeV neutrinos.