High statistic measurement of the K- -> pi0 e- nu decay form-factors
Abstract
The decay K- -> pi0 e- nu is studied using in-flight decays detected with the ISTRA+ spectrometer. About 920K events are collected for the analysis. The lambda+ slope parameter of the decay form-factor f+(t) in the linear approximation (average slope) is measured: lambda+(lin)= 0.02774 +- 0.00047(stat) +- 0.00032(syst). The quadratic contribution to the form-factor was estimated to be lambda'+ = 0.00084 +- 0.00027(stat) +- 0.00031(syst). The linear slope, which has a meaning of df+(t)/dt|_{t=0} for this fit, is lambda+ = 0.02324 +- 0.00152(stat) +- 0.00032(syst). The limits on possible tensor and scalar couplings are derived: f_{T}/f_{+}(0)=-0.012 +- 0.021(stat) +- 0.011$(syst), f_{S}/f_{+}(0)=-0.0037^{+0.0066}_{-0.0056}(stat) +- 0.0041(syst).
Cite
@article{arxiv.hep-ex/0404030,
title = {High statistic measurement of the K- -> pi0 e- nu decay form-factors},
author = {O. P. Yushchenko and S. A. Akimenko and G. I. Britvich and K. V. Datsko and A. P. Filin and A. V. Inyakin and A. S. Konstantinov and V. F. Konstantinov and I. Y. Korolkov and V. A. Khmelnikov and V. M. Leontiev and V. P. Novikov and V. F. Obraztsov and V. A. Polyakov and V. I. Romanovsky and V. M. Ronjin and V. I. Shelikhov and N. E. Smirnov and O. G. Tchikilev and V. A. Uvarov and V. N. Bolotov and S. V. Laptev and A. Yu. Polyarush},
journal= {arXiv preprint arXiv:hep-ex/0404030},
year = {2008}
}
Comments
11 pages, 8 figures. Accepted by Phys.Lett. B