CERN announces measurement of antimatter excess in space
The following is adapted from a press release issued today by CERN, the European Organization for Nuclear Research. Samuel Ting, the Thomas Dudley Cabot Professor of Physics at MIT and the spokesman for the international team of researchers running the Alpha Magnetic Spectrometer, also announced these results via webcast.The international team running the Alpha Magnetic Spectrometer (AMS) today announces the first results in its search for dark matter. The AMS paper, to be published in the journal Physical Review Letters, reports the observation of an excess of positrons in the cosmic ray flux.The AMS results are based on some 25 billion recorded events, including 400,000 positrons with energies between 0.5 GeV and 350 GeV (gigaelectronvolts, a unit of energy equal to one billion electron volts), recorded over a year and a half. This represents the largest collection of antimatter particles recorded in space. The positron fraction increases from 10 GeV...