A. Ranieri

Physics with the KLOE-2 experiment at the upgraded DA Phi NE

Investigation at a φ-factory can shed light on several debated issues in particle physics. We discuss: (i)xa0recent theoretical development and experimental progress in kaon physics relevant for the Standard Model tests in the flavor sector, (ii)xa0the sensitivity we can reach in probing CPT and Quantum Mechanics from time evolution of entangled-kaon states, (iii)xa0the interest for improving on the present measurements of non-leptonic and radiative decays of kaons and η/η′ mesons, (iv)xa0the contribution to understand the nature of light scalar mesons, and (v)xa0the opportunity to search for narrow di-lepton resonances suggested by recent models proposing a hidden dark-matter sector. We also report on the e+e− physics in the continuum with the measurements of (multi)hadronic cross sections and the study of γγ processes.

Limit on the production of a light vector gauge boson in phi meson decays with the KLOE detector

We present a new limit on the production of a light dark-force mediator with the KLOE detector at DA Phi NE. This boson, called U, has been searched for in the decay phi -> eta U, U -> e(+)e(-), analyzing the. decay eta -> pi(0)pi(0)pi(0) in a data sample of 1.7 fb(-1). No structures are observed in the e(+)e(-) invariant mass distribution over the background. This search is combined with a previous result obtained from the decay eta -> pi(+)pi(-)pi(0), increasing the sensitivity. We set an upper limit at 90% C.L. on the ratio between the U boson coupling constant and the fine structure constant of alpha/alpha < 1.7 x 10(-5) for 30 < M-U < 400 MeV and alpha/alpha <= 8 x 10(-6) for the sub-region 50 < M-U <210 MeV. This result assumes the Vector Meson Dominance expectations for the phi eta gamma* transition form factor. The dependence of this limit on the transition form factor has also been studied.

Search for a vector gauge boson in phi meson decays with the KLOE detector KLOE-2 Collaboration

The existence of a light dark force mediator has been tested with the KLOE detector at DAPHNE. This particle, called U, is searched for using the decay chain phi-->etaU, eta-->pi+pi-pi0, U-->e+e-. No evidence is found in 1.5 fb-1 of data. The resulting exclusion plot covers the mass range 5<M_U<470 MeV, setting an upper limit on the ratio between the U boson coupling constant and the fine structure constant, alpha/alpha, of<= 2x10^-5 at 90% C.L. for 50<M_U<420 MeV.

Precision measurement of σ(e+e−→π+π−γ)/σ(e+e−→μ+μ−γ) and determination of the π+π− contribution to the muon anomaly with the KLOE detector

We have measured the ratio

Test of CPT and Lorentz symmetry in entangled neutral kaons with the KLOE experiment

sigma(e^+e^-rightarrowpi^+pi^-gamma)/sigma(e^+e^-rightarrow mu^+mu^-gamma)

Measurement of the φ→π0e+e- transition form factor with the KLOE detector

, with the KLOE detector at DA

A new limit on the CP violating decay KS→3π0 with the KLOE experiment

Phi

Precision measurement of

NE for a total integrated luminosity of

\sigma(e^+e^-\rightarrow\pi^+\pi^-\gamma)/\sigma(e^+e^-\rightarrow \mu^+\mu^-\gamma)

sim

and determination of the

240 pb