CM-AMO Seminar | Precision Mass Measurement: The Cyclotron Frequency is not qB/m, does E=mc^2?, Speaker: Professor Dave Pritchard (Cecil and Ida Green Professor of Physics, MIT)
Thursday, November 10, 2011
335 West Hall
Speaker: Professor Dave Pritchard (Cecil and Ida Green Professor of Physics, MIT)We have developed an ion balance that has improved atomic and molecular mass measurement accuracy beyond 10^(-11). It compares the cyclotron frequency of two individual molecular or atomic ions trapped in a uniform magnetic field to find the mass ratio. Besides improving the mass of fundamental particles, we have discovered a correction to the cyclotron resonance formula, enabled a new route to determining the fine structure constant using simple physics, made the best measurement of the dipole moment of any charged molecule, recalibrated the x-ray wavelength standard, enabled a possible route to replace the artifact kilogram with an atomic mass standard, and made a precise test of E=mc^2. We can also weigh chemical bonds.