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Joined 2026-09-21 Message
Incoming links: Masatoshi Koshiba
Kamiokande 2026-10-18
Kamiokande, associated with Masatoshi Koshiba, was an underground water Cherenkov detector viewed by photomultipliers. Improved water purity and reduced background enabled solar neutrino observations. A concentration of reconstructed recoil directions toward the Sun distinguished a source signal above an approximately direction-independent background.[ref]
For solar neutrinos, Electron elastic scattering supplies a directional recoil, with different cross sections for active neutrino flavors. Neither the Homestake experiment deficit nor the SN 1987A neutrino burst alone established neutrino oscillation; later evidence compared complementary channels and propagation effects.[ref]
Nobel Lecture: Birth of neutrino astrophysics by Masatoshi Koshiba. pp. 1013, 1016–1018: scattering and combined oscillation evidence
Masatoshi Koshiba 2026-10-18
Portrait of Masatoshi Koshiba
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Nobel Prize in Physics in 2002 2026-10-18
One quarter each went to Raymond Davis Jr. and Masatoshi Koshiba for pioneering astrophysics through detection of cosmic neutrinos. One half went to Riccardo Giacconi for pioneering astrophysics leading to the discovery of cosmic X-ray sources.[ref]
The Nobel Prize in Physics 2002 by Nobel Prize Outreach. Individual official 2002 summary: Davis and Koshiba one quarter each for cosmic neutrinos; Giacconi one half for cosmic X-ray sources.