Neutron electric dipole moment using $N_f=2+1+1$ twisted mass fermions

Abstract

We evaluate the neutron electric dipole moment $|{\vec{d}}_N|$ using lattice QCD techniques. The gauge configurations analyzed are produced by the European Twisted Mass Collaboration using $N_f=2+1+1$ twisted mass fermions at one value of the lattice spacing of $a\simeq 0.082\mathrm{fm}$ and a light quark mass corresponding to $m_{\pi }\simeq 373\mathrm{MeV}$. Our approach to extract the neutron electric dipole moment is based on the calculation of the $CP$-odd electromagnetic form factor $F_3(Q^2)$ for small values of the vacuum angle $\theta$ in the limit of zero Euclidean momentum transfer $Q^2$. The limit $Q^2\to 0$ is realized either by adopting a parameterization of the momentum dependence of $F_3(Q^2)$ and performing a fit, or by employing new position space methods, which involve the elimination of the kinematical momentum factor in front of $F_3(Q^2)$. The computation in the presence of a $CP$-violating term requires the evaluation of the topological charge $\mathcal{Q}$. This is computed by applying the cooling technique and the gradient flow with three different actions, namely the Wilson, the Symanzik tree-level improved and the Iwasaki action. We demonstrate that cooling and gradient flow give equivalent results for the neutron electric dipole moment. Our analysis yields a value of $|{\vec{d}}_N|=0.045(6)(1)\bar{\theta }e\cdot \mathrm{fm}$ for the ensemble with $m_{\pi }=373$ MeV considered.

arXiv commentVersion accepted for publication in Phys. Rev. D.: 33 pages, 13 Figures

References in corpus (42)

• An Improved Experimental Limit on the Electric Dipole Moment of the Neutron
• Electric dipole moments as probes of new physics
• Properties and uses of the Wilson flow in lattice QCD
• Chirally improving Wilson fermions - I. O(a) improvement
• Trivializing maps, the Wilson flow and the HMC algorithm
• Light hadrons from lattice QCD with light (u,d), strange and charm dynamical quarks
• Vector Correlators in Lattice QCD: methods and applications
• Twisted-mass lattice QCD with mass non-degenerate quarks
• Chirally improving Wilson fermions
• The Static Approximation of Heavy-Light Quark-Systems - A Systematic Lattice Study
• Nucleon form factors and moments of generalized parton distributions using $N_f=2+1+1$ twisted mass fermions
• The Effective Chiral Lagrangian From Dimension-Six Parity and Time-Reversal Violation
• Light baryon masses with dynamical twisted mass fermions
• Comparison of the gradient flow with cooling in $SU(3)$ pure gauge theory
• Disconnected quark loop contributions to nucleon observables in lattice QCD
• Computing and deflating eigenvalues while solving multiple right hand side linear systems in Quantum Chromodynamics
• The electric dipole moment of the neutron from 2+1 flavor lattice QCD
• New insights into the neutron electric dipole moment
• Reducing cutoff effects in maximally twisted lattice QCD close to the chiral limit
• The Nucleon Electric Dipole Form Factor From Dimension-Six Time-Reversal Violation
• Scaling in SU(3) Pure Gauge Theory with a Renormalization Group Improved Action
• The Electric Dipole Form Factor of the Nucleon in Chiral Perturbation Theory to Sub-leading Order
• Baryon electric dipole moments from strong CP violation
• The electric dipole moment of the neutron in chiral perturbation theory
• Topological charge using cooling and the gradient flow
• Full QCD calculation of neutron electric dipole moment with the external electric field method
• O(a^2) corrections to the one-loop propagator and bilinears of clover fermions with Symanzik improved gluons
• Neutron electric dipole moment with external electric field method in lattice QCD
• Computing the hadronic vacuum polarization function by analytic continuation
• The electric dipole form factor of the nucleon
• The nucleon electric dipole moment with the gradient flow: the $\theta$-term contribution
• On the effects of heavy sea quarks at low energies
• A Fresh Look into the Neutron EDM and Magnetic Susceptibility
• Light hadrons from Nf=2+1+1 dynamical twisted mass fermions
• Reply to Comment on ``An Improved Experimental Limit on the Electric Dipole Moment of the Neutron''
• Neutron Electric Dipole Moment on the Lattice: a Theoretical Reappraisal
• The Neutron Electric Dipole Moment in the Instanton Vacuum: Quenched Versus Unquenched Simulations
• Finite-volume corrections to the CP-odd nucleon matrix elements of the electromagnetic current from the QCD vacuum angle
• The Neutron EDM in the SM : A Review
• One-loop lattice artifacts of a dynamical charm quark
• An upper limit to the electric dipole moment of the neutron from lattice QCD
• Hyperon and charmed baryon masses and nucleon excited states from lattice QCD

Cited by in corpus (28)

• New experimental approaches in the search for axion-like particles
• Constraining the top-Higgs sector of the Standard Model Effective Field Theory
• Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation
• Confirming the Existence of the strong CP Problem in Lattice QCD with the Gradient Flow
• On Lattice Calculation of Electric Dipole Moments and Form Factors of the Nucleon
• The Role of Lattice QCD in Searches for Violations of Fundamental Symmetries and Signals for New Physics
• Review of the electric dipole moment of light nuclei
• Neutron electric dipole moment using lattice QCD simulations at the physical point
• Contribution of the QCD $\Theta$-term to nucleon electric dipole moment
• Neutron and proton electric dipole moments from $N_f=2+1$ domain-wall fermion lattice QCD
• Topological susceptibility from twisted mass fermions using spectral projectors and the gradient flow
• Theta dependence in Holographic QCD
• Short flow-time coefficients of CP-violating operators
• Proof of the renormalizability of the gradient flow
• The axion-baryon coupling in SU(3) heavy baryon chiral perturbation theory
• Indirect Signs of the Peccei-Quinn Mechanism
• Novel applications of Lattice QCD: Parton distribution functions, proton charge radius and neutron electric dipole moment
• Position space method for the nucleon magnetic moment in lattice QCD
• Nucleon tomography. What can we do better today than Rutherford 100 years ago?
• Lattice QCD and the Neutron Electric Dipole Moment
• Progress in the Nucleon Electric Dipole Moment Calculations in Lattice QCD
• Recent progress in hadron structure from Lattice QCD
• The electric dipole moment of the neutron from $N_f=2+1+1$ twisted mass fermions
• Deuteron electric dipole moment from holographic QCD
• Present and future prospects for lattice QCD calculations of matrix elements for nEDM
• Computing Nucleon Electric Dipole Moment from lattice QCD
• New Physics Searches from Nucleon Matrix Elements in Lattice QCD
• One-loop matching of the LEFT to the QCD gradient flow