Super-Kamiokande(SK) is a 50-kiloton water Cherenkov detector built at 1000 m underground in Hida-city, Japan. It has been operational since 1996 and leading a wide range of neutrino measurements, including solar, atmospheric, and accelerator neutrinos, as well as searches for nucleon decays. In 2020, the SK detector underwent a major upgrade by dissolving Gadolinium into its pure water and started a new phase of the experiment as SK-Gd.  Thanks to Gadolinium’s large thermal neutron capture cross-section and subsequent emission of gamma-rays with total energy of ~8 MeV, neutron detection capability at SK has been significantly enhanced. One of the primary physics goals of SK-Gd is the world’s first observation of Diffuse Supernova Neutrino Backgrounds (DSNB). Past searches with the data from the pure-water phase of SK already ruled out some DSNB models with optimistic flux predictions. With the enhanced sensitivity of SK-Gd, we will be exploring an extremely interesting region of the DNSB flux predictions in the coming years. Furthermore, the successor of the SK detector, the Hyper-Kamiokande(HK) detector is now under construction. We are aiming to start observation at HK in 2027 and will continue to be at the forefront of CP-violation measurement in the leptonic sector, astrophysical neutrino observations, and nucleon decay searches. In this seminar, I will discuss recent hot topics from the Super-Kamiokande and Hyper-Kamiokande experiments.

開始日時	2021/11/19　16:00
終了日時	2021/11/19　17:30
講演者	Yasuhiro Nakajima (University of Tokyo)
会場	Zoom
連絡先	katsuro@post.kek.jp
言語	日本語
ウェブサイト	https://kds.kek.jp/event/39846/

概要

Super-Kamiokande(SK) is a 50-kiloton water Cherenkov detector built at 1000 m underground in Hida-city, Japan. It has been operational since 1996 and leading a wide range of neutrino measurements, including solar, atmospheric, and accelerator neutrinos, as well as searches for nucleon decays. In 2020, the SK detector underwent a major upgrade by dissolving Gadolinium into its pure water and started a new phase of the experiment as SK-Gd. Thanks to Gadolinium’s large thermal neutron capture cross-section and subsequent emission of gamma-rays with total energy of ~8 MeV, neutron detection capability at SK has been significantly enhanced. One of the primary physics goals of SK-Gd is the world’s first observation of Diffuse Supernova Neutrino Backgrounds (DSNB). Past searches with the data from the pure-water phase of SK already ruled out some DSNB models with optimistic flux predictions. With the enhanced sensitivity of SK-Gd, we will be exploring an extremely interesting region of the DNSB flux predictions in the coming years. Furthermore, the successor of the SK detector, the Hyper-Kamiokande(HK) detector is now under construction. We are aiming to start observation at HK in 2027 and will continue to be at the forefront of CP-violation measurement in the leptonic sector, astrophysical neutrino observations, and nucleon decay searches. In this seminar, I will discuss recent hot topics from the Super-Kamiokande and Hyper-Kamiokande experiments.