Neutrinos are tiny elementary particles that do not interact through the electromagnetic force. Almost like ghosts, they can literally go through walls and escape places that are inaccessible by other means, giving us a unique way of observing the interior of stars or nuclear reactors.
Hyper-Kamiokande – a cylindrical water tank that is 62 m high and 76 m in diameter – is a next-generation neutrino detector, which will be built inside a mountain 250 km northwest of Tokyo starting in 2020. The talk will give an overview on the process of designing and building a subterranean detector of this size, starting from preparations for cavern construction and ending with the design of photodetectors, electronics and data analysis.
In addition, the talk will cover selected areas of the physics programme of this detector. It will be explained how detecting neutrinos from our sun lets us figure out why the sun shines and how we can measure the temperature at its core to a precision of about 1%. Finally, I will explain how such a neutrino detector can help us watch, millisecond by millisecond, how giant stars explode in a supernova, creating many of the chemical elements that are necessary for life and computers to exist.