A Fresh Look into the Neutron EDM and Magnetic Susceptibility

Abstract

We reexamine the estimate of the neutron Electric Dipole Moment (NEDM) from chiral and QCD spectral sum rules (QSSR) approaches. In the former, we evaluate the pion mass corrections which are about 5% of the leading Log. results. However, the chiral estimate can be affected by the unknown value of the renormalizaton scale nu. For QSSR, we analyze the effect of the nucleon interpolating currents on the existing predictions. We conclude that previous QSSR results are not obtained within the optimal choice of these operators, which lead to an overestimate of these results by about a factor 4. The weakest upper bound |theta|< 2 10^-9 for the strong CP-violating angle is obtained from QSSR, while the strongest upper bound |theta|< 1.3 10^-10 comes from the chiral approach evaluated at the scale ν=M_N. We also re-estimate the proton magnetic susceptibility, which is an important input in the QSSR estimate of the NEDM.

Version to appear in Phys. Lett. B

References in corpus (2)

• Full QCD calculation of neutron electric dipole moment with the external electric field method
• Discrete Symmetries on the Light Front and a General Relation Connecting Nucleon Electric Dipole and Anomalous Magnetic Moments

Cited by in corpus (12)

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• Reevaluation of Neutron Electric Dipole Moment with QCD Sum Rules
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• The Electric Dipole Form Factor of the Nucleon in Chiral Perturbation Theory to Sub-leading Order
• Baryon electric dipole moments from strong CP violation
• Neutron Electric Dipole Moment Induced by the Strangeness Revisited
• Neutron electric dipole moment using lattice QCD simulations at the physical point
• Maximal CP and Bounds on the Neutron Electric Dipole Moment from P and CP Breaking
• Finite-volume corrections to the CP-odd nucleon matrix elements of the electromagnetic current from the QCD vacuum angle
• N to $\Delta$ transition amplitudes from QCD sum rules
• Charged Lepton-Flavor Violation in Beyond-Standard Models
• Parity- and Time-Reversal-Violating Moments of Light Nuclei