Monday, September 15, 1997
4:00 PM (refreshments 3:45)
Edgerton Hall, Room 34-101
EECS Colloquium
Abstract
Ion traps are revolutionizing precision mass spectrometry for three reasons: the mass is determined from a [cyclotron] frequency measurement, unlimited time is available for this measurement, and perturbations due to unknown space charge have eliminated by working with only one trapped ion at a time. Implementing this approach, which requires sophisticated superconducting electronics, has advanced the precision of mass determination by over an order of magnitude, and the sensitivity of mass spectrometers by approximately two orders of magnitude to the ultimate limit - one molecule. I shall discuss our experimental techniques, results, and ways to increase precision further, including squeezing the thermal noise to reduce uncertainties due to the relativistic mass shift.
Recent results have recalibrated the gamma ray spectrum by weighing gamma rays, and may help replacing the artifact kilogram with an atomic standard. Measuring the fine structure constant classically, determining the neutrino rest mass, and weighing chemical bonds are on the future agenda.
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Modified: Sep 5, 1997|
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