Limit on Lorentz and CPT Violation of the Proton Using a Hydrogen Maser
arXiv:physics/0008230 · doi:10.1103/PhysRevD.63.111101
Abstract
We present a new measurement constraining Lorentz and CPT violation of the proton using a hydrogen maser double resonance technique. A search for hydrogen Zeeman frequency variations with a period of the sidereal day (23.93 h) sets a clean limit on violation of Lorentz and CPT symmetry of the proton at the 10^{-27} GeV level.
4 pages, 3 figures. Submitted to Physical Review Letters