Test of spatial isotropy using a cryogenic torsion pendulum
Abstract
Motion of the earth through the cosmic neutrino background, or through certain kinds of vacuum states, produces a term of the form g(sigma) x v in the energy of an electron. To search for such a term, a cryogenic torsion pendulum carrying a transversely polarized magnet was used. Superconducting shields reduced magnetic torques. A sigma x v term would produce a sinusoidal oscillation of the pendulum with a period of one sidereal day. Such an oscillation was not detected, and a new limit of 8.5 x 10 to the -18th eV has been set for the splitting of the spin states of an electron at rest on the earth.
- Publication:
-
Physical Review Letters
- Pub Date:
- October 1987
- DOI:
- 10.1103/PhysRevLett.59.1784
- Bibcode:
- 1987PhRvL..59.1784P
- Keywords:
-
- Cryogenics;
- Earth Motion;
- Electron Energy;
- Electron Spin;
- Pendulums;
- Spatial Distribution;
- Liquid Helium;
- Magnetic Fields;
- Magnetic Moments;
- Nuclear Spin;
- Vacuum Chambers;
- 98.60.Df;
- 03.30.+p;
- Physics (General);
- Special relativity