Test of Lorentz Invariance with Spin Precession of Ultracold Neutrons

I. Altarev et al.
Phys. Rev. Lett. 103, 081602 – Published 20 August 2009


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<2×1020eV (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|<3×104eV/c2m.

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  • Received 19 May 2009


©2009 American Physical Society

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Vol. 103, Iss. 8 — 21 August 2009

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Heating up of Superconductors
January 27, 2017

This collection marks the 30th anniversary of the discovery of high-temperature superconductors. The papers selected highlight some of the advances that have been made to date, both in understanding why these compounds behave in the way they do, and in utilizing them in applications. The papers included in the collection have been made free to read.

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