The metastable Q 3Δ2 state of ThO: a new resource for the ACME electron EDM search

  title={The metastable Q 3$\Delta$2 state of ThO: a new resource for the ACME electron EDM search},
  author={X Wu and Zhang-Zhu Han and J Chow and D. G. Ang and C. Meisenhelder and Cristian D. Panda and Elizabeth West and G. Gabrielse and John M. Doyle and D. DeMille},
  journal={New Journal of Physics},
The best upper limit for the electron electric dipole moment was recently set by the ACME collaboration. This experiment measures an electron spin-precession in a cold beam of ThO molecules in their metastable H ( 3 Δ 1 ) state. Improvement in the statistical and systematic uncertainties is possible with more efficient use of molecules from the source and better magnetometry in the experiment, respectively. Here, we report measurements of several relevant properties of the long-lived Q ( 3 Δ 2… 

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