Recent measurements of form factors at NA48

Sergey Shkarovskiy, D. Melikhov, I. Volobuev
2017 EPJ Web of Conferences  
The NA48/2 experiment presents a final result of the charged kaon semileptonic decays form factors measurement based on 4.28 million K ± e3 and 2.91 million K ± µ3 selected decays collected in 2004. The result is competetive with other measurements in K ± µ3 mode and has a smallest uncertainty for K ± e3 , that leads to the most precise combined K ± l3 result and allows to reduce the form factor uncertainty of |V US |. KABES 2 KABES 1 Z collimator TAX 17, 18 Y Figure 1. Schematic side view of
more » ... atic side view of the NA48/2 beamline and detectors. Apart from that, a large statistics of K ± → π 0 l ± ν (K l3 ) events has been collected during a special data taking period of 2004 (l means e or µ lepton). Semileptonic kaon decays (K l3 ) offer the most ⋆
doi:10.1051/epjconf/201715803007 fatcat:n42kyke6kjbpdcevevjjnkjpnm