It was announced this week that the Hyper-Kamiokande experiment, a large water Cherenkov neutrino detector, will begin construction in Japan in 2020. "This experiment will be a real game-changer for the particle and astrophysics community," says Erin O'Sullivan, a postdoctoral associate at Stockholm University who is working on Hyper-Kamiokande. "There is something for everyone with this detector. World-leading nucleon decay limits will test physics from the earliest times of the Universe, a man-made beam of neutrinos will be pointed at the detector to test for an explanation of why our Universe is made of matter rather than antimatter, and for the first time we will see neutrinos from supernovae out to the Mpc-scale as well as make a precision measurement of the diffuse supernova neutrino background, which will tell us details about the supernova explosions that we haven't yet been able to access with other detection methods."


An design drawing for the instrument - a large container of water surrounded by light detectors


The Hyper-Kamiokande collaboration has over 300 scientists from 15 countries and 76 member institutions, including Stockholm University and the Oskar Klein Center. The detector consists of a cylindrical tank of water that will be a staggering 60 meters in height and 74 meters in diameter. Over 40,000 photosensors will line the wall of the tank to detect the tiny flashes of light that arise from neutrino interactions or nucleon decay byproducts. "Hyper-Kamiokande will be a beautiful piece of technology," says Dr. O'Sullivan, "and it will fundamentally change the way we see our world."

For more information, refer to the Hyper-Kamiokande webpage or the Next-Generation Neutrino Science Organization page.