THE 2000 WOLF FOUNDATION PRIZE IN PHYSICS
The Prize Committee for Physics has unanimously decided that the Prize for 2000 be jointly awarded to:
Raymond Davis Jr.
University of Pennsylvania,
Philadelphia, Pennsylvania, and
Brookhaven National Laboratory
Upton, New York, USA
University of Tokyo
for their pioneering observations of astronomical phenomena by detection of neutrinos, thus creating the emerging field of neutrino astronomy.
The observations of the elusive neutrinos of astrophysical origin, by Davis and by Koshiba, have opened a new window of opportunity for the study of astronomical objects, such as the sun and exploding stars, and the study of fundamental properties of matter. Davis and Koshiba developed complementary methods that have yielded important scientific results and have inspired the development of new neutrino detection experiments.
Professor Raymond Davis Jr. developed, through persistent and sustained efforts, the first large-scale radiochemical neutrino detectors and obtained the first measurement of the flux of neutrinos from the sun. Davis developed the techniques of extracting from a large detector volume, the few atoms of argon produced by incoming neutrinos. With the continuing theoretical support of John Bahcall, these measurements were shown to provide a very stringent test for theories of the solar interior.
Professor Masatoshi Koshiba led the design and construction of the Kamiokande detector and its successors. The Kamiokande detectors broke new ground, by recording the time of arrival, energy and direction of the incoming neutrinos. These attributes were essential in identifying neutrinos from Supernova 1987a; in identifying that low energy neutrinos originate in the sun, by measuring the direction of their source; and in measuring fluxes of neutrinos of different types, produced in the atmosphere by cosmic rays, providing the first evidence that neutrinos have mass.