## Tests of CPT and Lorentz symmetry from muon anomalous magnetic dipole moment

Y. V. Stadnik, B. M. Roberts, V. V. Flambaum, Phys. Rev. D 90, 045035 (2014)

doi:10.1103/PhysRevD.90.045035

arXiv:1407.5728

We derive the relativistic factor for splitting of the g-factors of a fermion and its anti-fermion partner, which is important for placing constraints on dimension-5, CPT-odd and Lorentz invariance-violating interactions from experiments performed in a cyclotron. From existing data, we extract limits (1$$\sigma$$) on the coupling strengths of a background field (including the field amplitude), which is responsible for such g-factor splitting, with an electron, proton and muon to be: $$| f^0_e | < 1.4 \times 10^{-25} \textrm{ GeV T}^{-1}$$, $$| f^0_p | < 2 \times 10^{-22} \textrm{ GeV T}^{-1}$$ and $$| f^0_u | < 5 \times 10^{-24} \textrm{ GeV T}^{-1}$$, respectively, in the laboratory frame. From existing data, we also extract limits (1$$\sigma$$) on the coupling strengths of related dimension-5 interactions of a background field with an electron, proton, neutron and muon: $$| \mathbf{d}_e^{(\perp)} | < 10^{-22} \textrm{ GeV T}^{-1}$$, $$| \mathbf{d}_p^{(\perp)} | < 10^{-23} \textrm{ GeV T}^{-1}$$, $$| \mathbf{d}_n^{(\perp)} | < 10^{-22} \textrm{ GeV T}^{-1}$$ and $$| \mathbf{d}_u^{(\perp)} | < 10^{-22} \textrm{ GeV T}^{-1}$$, respectively, in the laboratory frame.

Written on 1 August 2014