Speaker
Alexei Kulik
(Institute for Nuclear Research)
Description
The high statistics search for structure dependent (SD) components of radiation in K+ -> e+ nu pi0 gamma decay is performed by the OKA collaboration. The 4-dimensional distribution of about 3000 events of the decay in the phase space area of E(gamma)>30 MeV, Theta(e-gamma)<20 degrees analysed. The total SD contribution to branching ratio (including interference) is measured to (3 +- 5.4)x10^-6.
As the measurement errors don't allow to claim the observation, we set the 90% CL upper limit of 10^-5. This is in agreement with the Chiral Perturbation Theory (ChPT) predictions and is 5 times lower than the current PDG limit.
For the first time the chiral axial anomaly (AA) contribution is measured separately to (0+-2.3)x10^-6, < 3x10^-6 90% CL.
Primary author
Alexei Kulik
(Institute for Nuclear Research)
