Revisiting the pion's scalar form factor in chiral perturbation theory

Abstract

The quark-connected and the quark-disconnected Wick contractions contributing to the pion's scalar form factor are computed in the two and in the three flavour chiral effective theory at next-to-leading order. While the quark-disconnected contribution to the form factor itself turns out to be power-counting suppressed its contribution to the scalar radius is of the same order of magnitude as the one of the quark-connected contribution. This result underlines that neglecting quark-disconnected contributions in simulations of lattice QCD can cause significant systematic effects. The technique used to derive these predictions can be applied to a large class of observables relevant for QCD-phenomenology.

16 pages, 5 figures

References in corpus (3)

• Review of lattice results concerning low energy particle physics
• Chiral symmetry breaking and the Banks--Casher relation in lattice QCD with Wilson quarks
• Quark disconnected diagrams in chiral perturbation theory

Cited by in corpus (10)

• FLAG Review 2019
• Interactions of Charmed Mesons with Light Pseudoscalar Mesons from Lattice QCD and Implications on the Nature of the D_{s0}^*(2317)
• The scalar pion form factor in two-flavor lattice QCD
• Tetraquarks, hadronic molecules, meson-meson scattering and disconnected contributions in lattice QCD
• The size of the pion from full lattice QCD with physical $u$, $d$, $s$ and $c$ quarks
• Connected and Disconnected Contractions in Pion-Pion Scattering
• The scalar radius of the pion from Lattice QCD in the continuum limit
• Effective Field Theory in The Study of Long Range Nuclear Parity Violation on Lattice
• Novel Soft-Pion Theorem for Long-Range Nuclear Parity Violation
• Extracting the low-energy constant $L_0^r$ at three flavors from pion-kaon scattering