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تسجيل مستخدم جديدLepton anomalous magnetic moments in Lattice QCD+QED
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We present a lattice calculation of the Hadronic Vacuum Polarization (HVP) contribution to the anomalous magnetic moments of the electron, $a_e^{rm HVP}$, the muon, $a_mu^{rm HVP}$, and the tau, $a_tau^{rm HVP}$, including both the isospin-symmetric QCD term and the leading-order strong and electromagnetic isospin-breaking corrections. Moreover, the contribution to $a_mu^{rm HVP}$ not covered by the MUonE experimen, $a_{MUonE}^{rm HVP}$, is provided. We get $a_e^{rm HVP} = 185.8~(4.2) cdot 10^{-14}$, $a_mu^{rm HVP} = 692.1~(16.3) cdot 10^{-10}$, $a_tau^{rm HVP} = 335.9~(6.9) cdot 10^{-8}$ and $a_{MUonE}^{rm HVP} = 91.6~(2.0) cdot 10^{-10}$. Our results are obtained in the quenched-QED approximation using the QCD gauge configurations generated by the European (now Extended) Twisted Mass Collaboration (ETMC) with $N_f=2+1+1$ dynamical quarks, at three values of the lattice spacing varying from $0.089$ to $0.062$ fm, at several values of the lattice spatial size ($L simeq 1.8 div 3.5$ fm) and with pion masses in the range between $simeq 220$ and $simeq 490$ MeV.
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