Speaker
Dr
Xiaolin Kang
(INFN-LNF)
Description
The KLOE-2 experiment completed its data-taking at the e+e- DAPHNE collider
in Frascati, achieving the integrated luminosity goal of more than 5 fb-1 at
the phi peak. KLOE-2 represents the continuation of KLOE with an upgraded
detector and an extended physics program, which includes the study of light
meson properties and decay dynamics with unprecedented statistics. The new
data sample, together with the KLOE one, corresponds to more than 3x10^8
eta meson events. This statistics has been used to search for the P, CP
violating decay eta->pi+pi-, obtaining the most stringent upper limit for
this decay.
The eta -> pi0 gamma gamma decay is an important test of ChPT because of
its sensitivity to the p^6 term on both the branching ratio and the M(gg)
spectrum. A preliminary KLOE measurement, based on 450 pb-1, provided a
4 sigma's lower value w.r.t. the most accurate determination of the BR
from Crystal Ball. A new analysis with a larger data sample is in progress
to confirm this result. The same five photon final state is used to search
for the B boson, a postulated leptophobic mediator of dark forces.
The new four stations installed in KLOE-2 to tag electrons and positrons from
the reaction e+e- -> e+e-gamma*gamma* -> e+e-X, will give the opportunity to
investigate gamma-gamma physics at the phi resonance. Single pseudoscalar
production will improve the determination of the two-photon decay widths of
these mesons. The analysis for the pi0 final state is in progress, aiming to
achieve an accuracy of O(1%). Preliminary results will be presented.
Primary author
Dr
Xiaolin Kang
(INFN-LNF)
