James Glanz
Indianapolis--Eight months ago a group of experimenters at Los Alamos National Laboratory met with skepticism when they claimed to have found evidence of a positive mass for the neutrino--a wispy subatomic particle generally assumed to be massless. Now they're back, with twice the evidence. Last week the Liquid Scintillator Neutrino Detector (LSND) experiment reported that it has picked up 22 events in which neutrinos generated at the end of an accelerator changed identity before reaching the detector. That process can only take place if the neutrino has mass. If the LSND group is right--and some other researchers are warming to the claim--conventional physics may be in need of revision.