Test of Lorentz Invariance with Spin Precession of Ultracold Neutrons
Abstract
A clock comparison experiment, analyzing the ratio of spin precession frequencies of stored ultracold neutrons and Hg199 atoms, is reported. No daily variation of this ratio could be found, from which is set an upper limit on the Lorentz invariance violating cosmic anisotropy field b⊥<2×10-20eV (95% C.L.). This is the first limit for the free neutron. This result is also interpreted as a direct limit on the gravitational dipole moment of the neutron |gn|<0.3eV/c2m from a spin-dependent interaction with the Sun. Analyzing the gravitational interaction with the Earth, based on previous data, yields a more stringent limit |gn|<3×10-4eV/c2m.
- Publication:
-
Physical Review Letters
- Pub Date:
- August 2009
- DOI:
- arXiv:
- arXiv:0905.3221
- Bibcode:
- 2009PhRvL.103h1602A
- Keywords:
-
- 11.30.Cp;
- 04.80.Cc;
- 11.30.Er;
- 28.20.-v;
- Lorentz and Poincare invariance;
- Experimental tests of gravitational theories;
- Charge conjugation parity time reversal and other discrete symmetries;
- Neutron physics;
- Nuclear Experiment
- E-Print:
- 4 pages, 3 figures accepted for publication in Phys. Rev. Lett