From Hadronic Cross Section to the measurement of the Vacuum Polarization at KLOE: a fascinating endeavour

Abstract

The KLOE experiment at the $\varphi -factory$ DA$\Phi$NE in Frascati is the first to have employed Initial State Radiation (ISR) to precisely determine the $e^{+}{e}^{-}\to {\pi }^{+}{\pi }^{-}(\gamma )$ cross section below 1 GeV. Such a measurement is particularly important to test the Standard Model (SM) calculation for the $(g-2)$ of the muon, where a long standing 3$\sigma$ discrepancy is observed. I will review the ISR activity in KLOE in the last 18 years from the measurement of the hadronic cross section to the first direct determination of the time-like complex running $\alpha (s)$ in the region below 1 GeV.

13 pages, 8 figures. Contribution to the proceedings of the KLOE-2 Workshop on e+e- collision physics at 1 GeV, 26-28 October 2016 INFN - Laboratori Nazionali di Frascati, Italy

References in corpus (11)

• Update of the e^+e^-\toπ^+π^- cross section measured by SND detector in the energy region 400<\sqrt{s}<1000 MeV
• Measurement of sigma(e+ e- -> pi+ pi-) from threshold to 0.85 GeV^2 using Initial State Radiation with the KLOE detector
• Measuring the leading hadronic contribution to the muon g-2 via $\mu e$ scattering
• A new approach to evaluate the leading hadronic corrections to the muon g-2
• Measurement of the e+e- -> pi+pi- cross section with the CMD-2 detector in the 370-520 MeV c.m. energy range
• Photon pair production at flavour factories with per mille accuracy
• Leading-order hadronic contribution to the electron and muon g-2
• Measurement of the running of the fine structure constant below 1 GeV with the KLOE Detector
• Initial State Radiation: A success story
• Final state radiation and a possibility to test a pion-photon interaction model near two-pion threshold
• The HLS approach to $(g-2{)}_{\mu }$~: A Solution to the "$\tau$ versus $e^{+}{e}^{-}$" Puzzle

Cited by in corpus (2)

• The anomalous magnetic moment of the muon in the Standard Model
• The anomalous magnetic moment of the muon in the Standard Model: an update