The two-pion contribution to the hadronic vacuum polarization with staggered quarks

Abstract

We present results from the first lattice QCD calculation of the two-pion contributions to the light-quark connected vector-current correlation function obtained from staggered-quark operators. We employ the MILC collaboration's gauge-field ensemble with $2+1+1$ flavors of highly improved staggered sea quarks at a lattice spacing of $a\approx 0.15$ fm with a light sea-quark mass at its physical value. The two-pion contributions allow for a refined determination of the noisy long-distance tail of the vector-current correlation function, which we use to compute the light-quark connected contribution to HVP with improved statistical precision. We compare our results with traditional noise-reduction techniques used in lattice QCD calculations of the light-quark connected HVP, namely the so-called fit and bounding methods. We observe a factor of roughly three improvement in the statistical precision in the determination of the HVP contribution to the muon's anomalous magnetic moment over these approaches. We also lay the group theoretical groundwork for extending this calculation to finer lattice spacings with increased numbers of staggered two-pion taste states.

arXiv commentv2: Updated to reflect published version, added a multi-exponential matrix fit appendix

References in corpus (33)

• Leading hadronic contribution to the muon magnetic moment from lattice QCD
• High-precision scale setting in lattice QCD
• On the generalized eigenvalue method for energies and matrix elements in lattice field theory
• Calculation of the hadronic vacuum polarization contribution to the muon anomalous magnetic moment
• Lattice QCD ensembles with four flavors of highly improved staggered quarks
• Effective noise reduction techniques for disconnected loops in Lattice QCD
• Vector Correlators in Lattice QCD: methods and applications
• Lattice calculation of the lowest order hadronic contribution to the muon anomalous magnetic moment
• S and D-wave phase shifts in isospin-2 pi pi scattering from lattice QCD
• Hadron Scattering Lengths in Lattice QCD
• Hadronic vacuum polarization contribution to the anomalous magnetic moments of leptons from first principles
• Lattice calculation of the short and intermediate time-distance hadronic vacuum polarization contributions to the muon magnetic moment using twisted-mass fermions
• Window observable for the hadronic vacuum polarization contribution to the muon $g-2$ from lattice QCD
• Vus from pi and K decay constants in full lattice QCD with physical u, d, s and c quarks
• $B_{(s)}^0$-mixing matrix elements from lattice QCD for the Standard Model and beyond
• Covariant approximation averaging
• Consistency of hadronic vacuum polarization between lattice QCD and the R-ratio
• Electromagnetic and strong isospin-breaking corrections to the muon $g-2$ from Lattice QCD+QED
• Hadronic-vacuum-polarization contribution to the muon's anomalous magnetic moment from four-flavor lattice QCD
• The anomalous magnetic moment of the muon in the Standard Model: an update
• Low-energy couplings of QCD from current correlators near the chiral limit
• The hadronic vacuum polarization contribution to $a_{\mu }$ from full lattice QCD
• Electromagnetic corrections in hadronic processes
• Light-quark connected intermediate-window contributions to the muon $g-2$ hadronic vacuum polarization from lattice QCD
• The muon anomalous magnetic moment with staggered fermions: is the lattice spacing small enough?
• Studying the $\rho$ resonance parameters with staggered fermions
• Effective field theories for QCD with rooted staggered fermions
• Rho resonance, timelike pion form factor, and implications for lattice studies of the hadronic vacuum polarisation
• Renormalising vector currents in lattice QCD using momentum-subtraction schemes
• Model averaging approaches to data subset selection
• Improving meson two-point functions by low-mode averaging
• Hybrid calculation of hadronic vacuum polarization in muon g-2 to 0.48\%
• $\pi \pi$ scattering in partially-quenched twisted-mass chiral perturbation theory