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A VMD Estimate of the Muon g-2 A HLS based approach. M. Benayoun LPNHE Paris 6/7. OUTLINE. Model & Method Symmetry Breaking : BKY & ( ρ , ω , φ ) mixing Global Fit : t vs e + e - Global Fit : e + e - → π π / KKbar / π γ / η γ / π π π ππ contribution to g-2
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A VMD Estimate of the Muon g-2 A HLS basedapproach M. Benayoun LPNHE Paris 6/7 M. Benayoun, VMD & g-2 estimates
OUTLINE • Model & Method • Symmetry Breaking : BKY & (ρ,ω,φ) mixing • Global Fit : t vs e+ e- • Global Fit : e+e- → π π/KKbar /πγ/ηγ/π ππ • ππ contribution to g-2 • VMD estimate of HVP and g-2 • Conclusions M. Benayoun, VMD & g-2 estimates
HLS : A VMD Model (I) • The HiddenLocalSymmetry model is: • A unifiedVMDframeworkincluding e+e- → π π/KKbar /πγ/ηγ/π ππ& τ→ππντ& PVγcouplings&η/η’ γπ π/γγ& …… • Few basic parameters : e, fπ,Vud,Vus, a (≈2), g ,… • PresentLimits : • Up to the ≈ φ mass region( 1.05 GeV) • No scalarsmesons, no ρ’, no ρ’’ …… M.Bando et al. Phys. Rep. 164 (1988) 217 M. Harada & K. Yamawaki Phys. Rep. 381 (2003) 1 M. Benayoun, VMD & g-2 estimates
NSK2:: Breaking the HLS Model Breaking the HLS Model HLS not enoughFlexible to reallyaccount for data • Needbreakingschemes to become operating: • BKY mechanism • vectormesonmixing M.Bando et al. Nucl. Phys. B259 (1985) 493 A. Bramon et al. Phys. Lett. B345 (1995) 263 M.Benayoun et al. Phys. Rev. D58 (1998) 074006 M.Benayoun et al. EPJ C55 (2008) 199 M.Benayoun et al. EPJ C65 (2010) 211 M. Benayoun, VMD & g-2 estimates
HLS and the BKY Mechanism • Define • Then • Standard HLS Lagrangians • BKY breaking : • Full HLS Lagrangian : • BKY Breaking Matrix : Diag PS fieldmatrix M. Hashimoto, Phys. Rev. D54 (1996) 5611 M. Benayoun et al, arXiv:1106.1315 M. Benayoun, VMD & g-2 estimates
Isospin Breaking : Vector Field Mixing I • treelevel:: idealvectorfields≡mass eigenstates • Vector Mass TermDiagonalization: • one loop:: s-dependenttransitions among R1 fields F. Jegerlehner & R. Szafron EPJ C71 (2011) 1632 C. Wolfe&K. Maltman, Phys. Rev. D80 (2009)114024 M. Benayoun, VMD & g-2 estimates
Isospin Breaking : Vector Field Mixing II • At one loop, the HLS Lagrangian piece induces s-dependenttransitions among R1 fields isospin symmetry breaking : M. Benayoun, VMD & g-2 estimates
Transitions at one loop • Define the loops : = K+ K- , = K0K0 Then, beside self-masses : → + ~ ε2(s) ≠ 0 always →- ≠ 0 by isospin brk →- ~ ε1(s) VVP Lagrangian K*K loops // Yang-Mills K*K*loops f(s) M. Benayoun, VMD & g-2 estimates
The Mass Matrix Eigen System At one loop: As : Solveperturbatively M. Benayoun, VMD & g-2 estimates
From Ideal To Physical Fields Physical Fields R1 Fields M. Benayoun, VMD & g-2 estimates
Analysis Method GLOBAL FIT to the largest possible data set • Why ? • Check VMD constraintswellaccepted by DATA? (correct lineshapes & yields with Proba. OK) • IF YES ↔ theoreticalcorrelationsfulfilled by DATA →→ improvedparameters • HLS formfactors& fit parameters values &errors& covariance matrix→ contributions to g-2 • Procedurefullyblind to g-2 M. Benayoun, VMD & g-2 estimates
Channels Considered • Non-Anomalous annihilations : e+e- → π π/ or decays : τ→ππντ(plays as constraintonly!) • AnomalousProcesses : e+e- → π γ/ηγ/π ππ(Anomalous FKTUY Effective Lagrangianpieces) • Radiative decayswidths (VPγ, η/η’→ππγ) OVERCONSTRAINED MODEL & BreakingScheme M. Benayoun, VMD & g-2 estimates
Channels Considered • Non-Anomalous annihilations : e+e- → π π/ or decays : τ→ππντ(constraint) • AnomalousProcesses : e+e- → π γ/ηγ/π ππ(Anomalous Effective Lagrangianpieces) • Radiative decayswidths (VPγ, η/η’→ππγ) • ISR data : NOT INCLUDEDOVERCONSTRAINED MODEL & BreakingScheme Relying on more than 40 (scan) data sets M. Benayoun, VMD & g-2 estimates
V π π Couplings: I=1 part of ω and φ Mixing Angles I=1 terms *Atleadingorder : ρtermunchanged(I=1 part) *smalls-dependentω and φcouplings (I=1 part) * Charged and neutralrho’s: samecoupling to pions M. Benayoun, VMD & g-2 estimates
ρ couplings to γ/W • (γ/W) V transitions : = + Full agreement between data One loop corrections M. Benayoun, VMD & g-2 estimates
ρ couplings to γ/W • (γ/W) V transitions : = + Full agreement between data One loop corrections M. Benayoun, VMD & g-2 estimates
ρ couplings to γ/W • (γ/W) V transitions : = + Full agreement between data One loop corrections M. Benayoun, VMD & g-2 estimates
ρ couplings to γ/W Re[F(s)] Im[F(s)] M. Benayoun, VMD & g-2 estimates
Dipion Spectra M. Benayoun, VMD & g-2 estimates
e+e-Fit Residuals e+e- Data M. Benayoun, e+ e- versus tau
Tau Fit Residuals M. Benayoun, VMD & g-2 estimates
Tau Residuals M. Benayoun, VMD & g-2 estimates
NSK18:: Dipion Mass Spectrum • s-dependent (missing) effect ! M. Davier NP Proc. Supp. 169 (2007) 288 M. Benayoun, VMD & g-2 estimates
3-pion Data M. Benayoun, VMD & g-2 estimates
e+e- → K Kbar Data K+ K- KL KS M. Benayoun, VMD & g-2 estimates
e+e- → K Kbar Data Ratio K+ K- KL KS M. Benayoun, VMD & g-2 estimates
e+e- → π0 γ M. Benayoun, VMD & g-2 estimates
e+e- → ηγ Data M. Benayoun, VMD & g-2 estimates
Effect of Global Fitting on aµ(ππ) L.O. Contribution of ππ to g-2 Integratedfrom 0.630 to 0.958 GeV/c (x10-10) FSR Corrected • Reconstructed value consistent with exp. average • Global fits provideimproveduncertainties • Probabilitiesprovided by the (underlying) global fits M. Benayoun, VMD & g-2 estimates
Effect of Global Fit on aµ(ππ) L.O. Contribution of ππ to g-2 Integratedfrom 0.630 to 0.958 GeV/c (x10-10) • Reconstructed value consistent with exp. average • Global fits provideimproveduncertainties • Probabilitiesprovided by the (underlying) global fits M. Benayoun, VMD & g-2 estimates
Effect of Global Fit on aµ(ππ) L.O. Contribution of ππ to g-2 Integratedfrom 0.630 to 0.958 GeV/c (x10-10) • Reconstructed value consistent with exp. average • Global fits provideimproveduncertainties • Probabilitiesprovided by the (underlying) global fits M. Benayoun, VMD & g-2 estimates
Contributions to g-2 up to F () Excl. ISR Uncertaintiesuniformlyimproved by a factor 2 M. Benayoun, VMD & g-2 estimates
VMD estimate of LO HVP Below 1.05 GeV • Most of Hadronic VP estimatedfromour Model (574.76 ± 2.10/ 572.82 ± 1.90) • Missingchannels(ηπ π, π π π π, etc…) HVP estimatedfrom data (1.55 ± 0.57) Above 1.05 GeV • LO HVP estimatedfrom data and pQCD (111.41 ± 4.10) • Total LO HVP : B → 687.72 ± 4.63 //A → 685.78 ± 4.55 M. Benayoun, VMD & g-2 estimates
VMD estimate of g-2 • LO HVP + HO HVP + LBL +QED +EW give aµ= (11 659 175.37 ± 5.31) 10-10 (B) Or aµ= (11 659 173.43 ± 5.25) 10-10 (A) M. Benayoun, VMD & g-2 estimates
VMD estimate of g-2 M. Benayoun, VMD & g-2 estimates
Conclusions 1/ HLS with BKY and Vector Meson Mixing provides a good simultaneous fit of e+e- → → π π/K+K-/ KLKS/ π γ/ηγ/π ππ 2/ A simultaneous account of e+e- → → π π& τ→ππντ 3/ VMD physics correlations improveg-2 (Uncertainty : HVP up to f uniformly improved by 2) M. Benayoun, VMD & g-2 estimates
Backup Slides M. Benayoun, VMD & g-2 estimates
NSK1:: HLS : A VMD Model (I) • The HiddenLocalSymmetry model is: • A unifiedVMDframeworkincluding e+e- → π π/Kkbar /πγ/ηγ/π ππ& τ→ππντ& PVγcouplings&η/η’ γπ π/γγ& …… • Few basic parameters : e, fπ,Vud,Vus, a (≈2), g ,… • PresentLimits : • Up to the ≈ φ mass region( 1.05 GeV) • No scalarsmesons, no ρ’, no ρ’’ …… M.Bando et al. Phys. Rep. 164 (1988) 217 M. Harada & K. Yamawaki Phys. Rep. 381 (2003) 1 M. Benayoun, VMD & g-2 estimates
VMD :: The HLS Framework • HiddenLocal Symmetry Model (HLS) as a whole LA, LV, LYM , Lanomalous (π/K formfactors, VPPP, γPPP, VPγ & Pγγcouplings) • BKY-like flavor U(3)/SU(3) breakingmechanisms M.Bando, T. Kugo & K. Yamawaki Phys. Rep. 164 (1988) 217 M. Harada & K. Yamawaki Phys. Rep. 381 (2003) 1 M.Benayoun & H.O’Connell PR D 58 (1998) 074006 M.Bando, T. Kugo & K. Yamawaki Phys. Rep. 164 (1988) 217 A. Bramon, A. Grau & G. Pancheri PL B 345 (1995) 263 M. Benayounet al. PR D 59 (1999) 114027 G. Morpurgo PR D 42 (1990) 1497 M. Benayoun, L. DelBuono & H. O’Connell EPJ C 17 (2000) 593 M. Benayoun et al. EPJ C 55 (2008) 139 M. Benayoun, VMD & g-2 estimates
The HiddenLocal Symmetry Model :The Non-AnomalousSector • Define • Define covariant derivatives • Then and • The Full HLS Lagrangian : PS fieldmatrix Expandedform: M.Benayoun & H.O’Connell PR D 58 (1998) 074006 UniversalVectorCoupling M. Benayoun, VMD & g-2 estimates
The Covariant Derivatives • Covariant derivatives ≠ for left- right-ξ fields : • With : T± is CKM matrix reduced to Vus and Vud terms M. Benayoun, VMD & g-2 estimates
Anomalous Annihilations/Decays • Non-Anomalous annihilations : e+e- → π π/ or decays : τ→ππντ • AnomalousProcesses : e+e- → π γ/ηγ/π ππ :: Other Effective Lagrangianpieces M. Benayoun, VMD & g-2 estimates
SIDE RESULT : Prediction for η/η’→ ππγ M. Benayoun et al. ArXiv 0907.4047 Г(η’→ ππγ)=53.11±1.47 PDG : 60±5 keV Г(η→ ππγ)=55.82±0.83 PDG : 60±4 eV Lineshapes and yields : tests for g valueand ρ0 lineshape M. Benayoun, VMD & g-2 estimates
BELLE/ALEPH/CLEO M. Benayoun, VMD & g-2 estimates