Electric Dipole Moment of the Neutron from 2+1 Flavor Lattice QCD.

  title={Electric Dipole Moment of the Neutron from 2+1 Flavor Lattice QCD.},
  author={Feng-Kun Guo and R. Horsley and Ulf-G. Mei{\ss}ner and Y. Nakamura and Holger Perlt and Paul E. L. Rakow and G. Schierholz and Arwed Schiller and James Zanotti},
  journal={Physical review letters},
  volume={115 6},
We compute the electric dipole moment d(n) of the neutron from a fully dynamical simulation of lattice QCD with 2+1 flavors of clover fermions and nonvanishing θ term. The latter is rotated into a pseudoscalar density in the fermionic action using the axial anomaly. To make the action real, the vacuum angle θ is taken to be purely imaginary. The physical value of dd(n) is obtained by analytic continuation. We find d(n)=-3.9(2)(9)×10(-16) θ  e cm, which, when combined with the experimental limit… 

Figures and Tables from this paper

Neutron Electric Dipole Moment on the Lattice
For the neutron to have an electric dipole moment (EDM), the theory of nature must have T, or equivalently CP, violation. Neutron EDM is a very good probe of novel CP violation in beyond the standard
Progress in the Nucleon Electric Dipole Moment Calculations in Lattice QCD
Electric dipole moments (EDMs), which are sought as evidence of CP violation, require lattice calculations to connect constraints from experiments to limits on the strong CP violation within QCD or
QCD θ-vacuum energy and axion properties
At low energies, the strong interaction is governed by the Goldstone bosons associated with the spontaneous chiral symmetry breaking, which can be systematically described by chiral perturbation
Computing Nucleon Electric Dipole Moment from lattice QCD
Electric dipole moments (EDMs) of nucleons and nuclei are actively considered as direct evidence of the CP violation. Calculations of nucleon EDMs on lattice are required to connect the quark- and
Recent progress in hadron structure from Lattice QCD
&We review recent progress in hadron structure using lattice QCD simulations, with main focus in the evaluation of nucleon quantities such as the axial and tensor charges, and the spin content of the
Electric Dipole Moment Results from lattice QCD
We utilize the gradient flow to define and calculate electric dipole moments induced by the strong QCD $\theta$-term and the dimension-6 Weinberg operator. The gradient flow is a promising tool to
Novel applications of Lattice QCD: Parton Distributions, proton charge radius and neutron electric dipole moment
We briefly discuss the current status of lattice QCD simulations and review selective results on nucleon observables focusing on recent developments in the lattice QCD evaluation of the nucleon form
Confirming the existence of the strong CP problem in lattice QCD with the gradient flow
We calculate the electric dipole moment of the nucleon induced by the QCD theta term. We use the gradient flow to define the topological charge and use $N_f = 2+1$ flavors of dynamical quarks
Nucleon Structure and the Neutron Electric Dipole Moment from Twisted Mass Lattice QCD
Recent results on nucleon structure using twisted mass lattice QCD simulated with a quark mass yielding the physical pion mass are presented. Namely, the nucleon axial charges and moments of parton
Dimension-5 CP -odd operators: QCD mixing and renormalization
Here, we study the off-shell mixing and renormalization of flavor-diagonal dimension-five T- and P-odd operators involving quarks, gluons, and photons, including quark electric dipole and


Full QCD calculation of neutron electric dipole moment with the external electric field method
We have calculated the neutron electric dipole moment (EDM) in the presence of the $CP$ violating $\ensuremath{\theta}$ term in lattice QCD with two-flavor dynamical clover quarks, using the external
The Electric dipole moment of the nucleon from simulations at imaginary vacuum angle theta
We compute the electric dipole moment of proton and neutron from lattice QCD simulations with N_f=2 flavors of dynamical quarks at imaginary vacuum angle theta. The calculation proceeds via the CP
Baryon electric dipole moments from strong CP violation
A bstractThe 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
Properties and uses of the Wilson flow in lattice QCD
Theoretical and numerical studies of the Wilson flow in lattice QCD suggest that the gauge field obtained at flow time t > 0 is a smooth renormalized field. The expectation values of local
Improved experimental limit on the electric dipole moment of the neutron.
The results may be interpreted as an upper limit on the neutron EDM of |d(n)|< 2.9 x 10(-26)e cm (90% C.L.).
Feynman-Hellmann approach to the spin structure of hadrons
We perform a Nf = 2 + 1 lattice QCD simulation to determine the quark spin fractions of hadrons using the Feynman-Hellmann theorem. By introducing an external spin operator to the fermion action, the
Improved experimental limit on the electric dipole moment of the neutron.
An experimental search for an electric dipole moment (EDM) of the neutron has been carried out at the Institut Laue-Langevin, Grenoble. Spurious signals from magnetic-field fluctuations were reduced
Flavor blindness and patterns of flavor symmetry breaking in lattice simulations of up, down, and strange quarks
QCD lattice simulations with 2+1 flavours (when two quark flavours are mass degenerate) typically start at rather large up-down and strange quark masses and extrapolate first the strange quark mass
Topological susceptibility and the sampling of field space in Nf = 2 lattice QCD simulations
A bstractWe present a measurement of the topological susceptibility in two flavor QCD. In this observable, large autocorrelations are present and also sizable cutoff effects have to be faced in the