1307.5604 (U. Schmidt et al.)

Probing Physics beyond the Standard Model with He/Xe clock comparison
experiments    [PDF]

U. Schmidt, F. Allmendinger, W. Heil, S. Karpuk, A. Scharth, Y. Sobolev, K. Tullney, S. Zimmer

The comparison of the free precession of co-located 3He-129Xe spins (clock comparison) enables us to search for very tiny nonmagnetic spin interactions. With our setup we could establish new limits for Lorentz invariance violating interactions of spins with a relic background field which permeates the Universe and points in a preferred direction in space.

View original: http://arxiv.org/abs/1307.5604