REVIEW 9 cited by
Isospin-breaking effects in the two-pion contribution to hadronic vacuum polarization
Not yet reviewed by Pith; the record is open.
This paper has not been read by Pith yet. Machine review is queued; the pith claim, tier, and objections will appear here once it completes.
SPECIMEN: schema-true, not a live event
T0 review · schema-true
One-sentence machine reading of the paper's core claim.
pith:XXXXXXXX · record.json · timestamp
Isospin-breaking effects in the two-pion contribution to hadronic vacuum polarization
read the original abstract
Isospin-breaking (IB) effects in the two-pion contribution to hadronic vacuum polarization (HVP) can be resonantly enhanced, if related to the interference of the $\rho(770)$ and $\omega(782)$ resonances. This particular IB contribution to the pion vector form factor and thus the line shape in $e^+e^-\to \pi^+\pi^-$ can be described by the residue at the $\omega$ pole - the $\rho$-$\omega$ mixing parameter $\epsilon_\omega$. Here, we argue that while in general analyticity requires this parameter to be real, the radiative channels $\pi^0\gamma$, $\pi\pi\gamma$, $\eta\gamma$ can induce a small phase, whose size we estimate as $\delta_\epsilon=3.5(1.0)^\circ$ by using a narrow-width approximation for the intermediate-state vector mesons. We then perform fits to the $e^+e^-\to \pi^+\pi^-$ data base and study the consequences for the two-pion HVP contribution to the anomalous magnetic moment of the muon, its IB part due to $\rho$-$\omega$ mixing, and the mass of the $\omega$ resonance. We find that the global fit does prefer a non-vanishing value of $\delta_\epsilon=4.5(1.2)^\circ$, close to the narrow-resonance expectation, but with a large spread among the data sets, indicating systematic differences in the $\rho$-$\omega$ region.
Forward citations
Cited by 9 Pith papers
-
Pion $\beta$ decay and $\tau\to\pi\pi\nu_\tau$ beyond leading logarithms
Pion β decay and τ→ππν short-distance radiative corrections are matched at NLL accuracy with evanescent-scheme dependence cancelled, giving Δ_RC^{πℓ}=0.03403(11) and a τ-HVP isospin-breaking shift of −0.07(4)×10^-10.
-
Radiative return at NLOPS accuracy
First implementation of NLO corrections matched to a parton shower for the radiative processes e+e−→π+π−γ and e+e−→μ+μ−γ, including ISR, FSR and their interference.
-
Dispersive analysis of the $J/\psi\to\pi^0 \gamma^\ast$ transition form factor with $\rho$-$\omega$ mixing effects
Dispersive analysis with ρ-ω mixing produces a two-parameter fit describing BESIII data on the J/ψ→π⁰γ* form factor from 0 to 2.8 GeV and extracts a (62 ± 21)° relative phase between strong and electromagnetic modes.
-
Comparison of the hadronic vacuum polarization between hadronic $\tau$-decay data and lattice QCD
Isospin-corrected inclusive τ spectral functions yield light-quark-connected HVP and window quantities consistent with lattice QCD, but the 2π⁻π⁺π⁰ mode differs significantly from e⁺e⁻-based Pais expectations.
-
Muon $g$$-$2: correlation-induced uncertainties in precision data combinations
A general framework quantifies correlation-induced uncertainties in precision data combinations and applies it to e+e- to hadrons cross sections for muon g-2 HVP determinations.
-
Field-theoretic versus data-driven evaluations of electromagnetic corrections to hadronic vacuum polarization in $(g-2)_\mu$
Virtual electromagnetic corrections largely cancel radiative-channel contributions in data-driven HVP evaluations for muon g-2, reconciling timelike and spacelike methods via a VMD model.
-
A dispersive method to study CP asymmetries in hadronic multi-body $B$ decays
The large localized CP asymmetry in B±→K±π+π− arises from a dip in the CP-conserving rate, not enhanced CP violation, and the non-resonant isospin-2 S-wave is essential — per a 13-parameter dispersive fit to LHCb's an...
-
The anomalous magnetic moment of the muon in the Standard Model: an update
The updated SM prediction for the muon anomalous magnetic moment is 116592033(62)×10^{-11}, showing no tension with the experimental average of 38(63)×10^{-11}.
-
Comparison of the hadronic vacuum polarization between hadronic $\tau$-decay data and lattice QCD
Lattice QCD and tau-decay dispersive calculations of isospin-one HVP generally agree, except for a significant difference in the 2π−π+π0 four-pion mode contribution to window quantities.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.