Number 138 (Story #3), July 26, 1993 by Phillip F. Schewe and Ben Stein THE LIQUID SCINTILLATOR NEUTRINO DETECTOR (LSND) at Los Alamos will provide the best terrestrial limits on oscillations between electron- and muon-type neutrinos; such oscillations may be at least partially responsible for the "solar neutrino problem" insofar as electron neutrinos from the sun that turn into muon neutrinos on their way toward the Earth would not be spotted by detectors sensitive only to electron neutrinos. At Los Alamos a beam of neutrinos will enter a 9-m-long tank containing 200 tons of liquid scintillator; neutrino and antineutrino interactions will be signalled by brief bursts of light. Two years of data collection (starting this summer) should provide limits on neutrino oscillation---expressed in terms of the square of the mass difference between muon and electron neutrinos (assuming that at least one neutrino species has a nonzero mass)---of about 4 x 10**-2 eV**2. (CERN Courier, Jul 1993.)