Word: franzinis
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...billionth of a second before breaking down into three smaller particles called pions-one positive, one negative, one without any electrical charge. According to the laws of symmetry, the positive and negative pions should have identical energies. But when a team led by Columbia University's Dr. Paolo Franzini examined 1,441 photographs of eta-meson decay in the Brookhaven bubble chamber (TIME, July 8), they found that in 53% of the photographs the positive pion apparently had more energy than its negative counterpart-a significant violation of symmetry...
Because the Brookhaven bubble chamber has a fixed magnetic field, the positive pions that Franzini studied always curved in one direction, while the negative pions went the other way. If the field had been uneven for any reason, the higher positive-pion energy levels detected at Brookhaven might well have been erroneous. In the CERN spark chamber, the magnetic field was periodically reversed to make sure that positive and negative pions would both be subject to any variations in the field...
Though most scientists at the Berkeley meeting privately sided with the CERN findings, none would state flatly that symmetry had, after all, been restored. Franzini's group is preparing a new round of experiments at Brookhaven in an attempt to confirm the violations they reported; still another team led by Columbia University Physicist Leon Lederman will attempt a similar experiment, and the CERN scientists plan to make more tests of their own. "The evidence from the CERN experiments is by no means conclusive," says Franzini defiantly. "Many more experiments are needed before we can say who is right...
This was just what Columbia's Dr. Paolo Franzini had in mind when he went to work with Brookhaven's synchrotron in January 1965. Along with his wife, Dr. Juliet Lee-Franzini, Drs. Charles Baltay and Lawrence Kirsch, he fired particles called pi mesons into a bubble chamber filled with liquid deuterium. About one-thirtieth of the times that a pi meson hit a deuterium nucleus, out came the eta meson, which decays into three pions. The pions streaked through the bubble chamber, the positive leaving a line that curved to the right, the negative peeling...
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