Seminars

Lecturer: Prof. Gerald Gabrielse (Harvard)
Date: 2008-02-12 10:30
Place: Aniara

Home-made Atoms and Cold Antihydrogen

Gerald Gabrielse
Leverett Professor of Physics
Harvard University

Abstract
A single electron is isolated in space by itself for months at a time. Its circular cyclotron motion in a magnetic field is cooled so much that the quantum structure of this motion is clearly observed, as are quantum jumps between the lowest energy levels caused by 4 K blackbody radiation. This "home-made" atom, an electron bound to our apparatus instead of an atomic nucleus, is used to probe the electron with great precision. We have measured the electron's intrinsic magnetic moment, its so-called g value, to about 3 parts in 10^{13}. This is more accurate than any other measurement of this fundamental property of the electron by a factor of 15. This measurement, plus accurate QED theory, determines the fine structure constant about 20 times more accurately than does any other measurement method. One interesting application is the use of our measurement to constrain the existence of low-mass dark matter particles.

New Measurement of the Electron Magnetic Moment and the Fine Structure Constant [arXiv]

Created 2008-01-11 08:45:26 by Mats Holmström
Last changed 2008-02-06 08:44:48 by Mats Holmström