Journal of High Energy Physics

, 2012:97 | Cite as

Baryon electric dipole moments from strong CP violation



The electric dipole form factors and moments of the ground state baryons are calculated in chiral perturbation theory at next-to-leading order. We show that the baryon electric dipole form factors at this order depend only on two combinations of low-energy constants. We also derive various relations that are free of unknown low-energy constants. We use recent lattice QCD data to calculate all baryon EDMs. In particular, we find dn = −2.9 ± 0.9 and dp = 1.1 ± 1.1 in units of 10−16e θ0 cm. Finite volume corrections to the electric dipole moments are also worked out. We show that for a precision extraction from lattice QCD data, the next-to-leading order terms have to be accounted for.


Chiral Lagrangians Lattice QCD CP violation 


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Copyright information

© SISSA, Trieste, Italy 2012

Authors and Affiliations

  1. 1.Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical PhysicsUniversität BonnBonnGermany
  2. 2.Institute for Advanced Simulation, Institut für Kernphysik and Jülich Center for Hadron PhysicsJARA-FAME and JARA-HPC, Forschungszentrum JülichJülichGermany

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