Abstract

We performed a search for neutron spin coupling to a Lorentz- and -violating background field using a magnetometer with overlapping ensembles of K and atoms. The comagnetometer is mounted on a rotary platform for frequent reversal of its orientation. We measure sidereal oscillations in the signal to search for anomalous spin coupling of extra-solar origin. We determine the equatorial components of the background field interacting with the neutron spin to be b˜Xn=(0.1±1.6)×10-33  GeV and b˜Yn=(2.5±1.6)×10-33  GeV, improving on the previous limit by a factor of 30. This measurement represents the highest energy resolution of any spin anisotropy experiment.

Date

October 5, 2010

Authors

JM Brown, SJ Smullin, TW Kornack, MV Romalis

Journal

Physical review letters

Volume

105

Issue

15

Pages

151604

Publisher

American Physical Society