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Scientists quietly announce a potentially huge discovery in physics

published by Houston Chronicle
Apr 16, 2013

Between 2006 and 2008 about four dozen physicists buried 19 Germanium-based detectors and 11 silicon-based detectors deep in a mine in Minnesota. They believed the Germanium detectors might be just right to capture the rare, but theoretically possible collision between a WIMP and an atomic nucleus. The silicon detectors were just there to confirm the result -- i.e. if a Germanium detector recorded such a collision and a silicon detector did not, that would be good evidence for a WIMP. Theoretical physicists guessed that WIMPs would be about 50 times the size of a proton. Because mass and energy are equivalent thanks to Einstein's E=mc2, particle physicists measure mass in energy units. A proton has a mass of 1 billion electron volts, or 1 GeV. Physicists thought WIMPs might have a mass of about 50 GeV.