Volume 414 - 41st International Conference on High Energy physics (ICHEP2022) - Quark and Lepton Flavour Physics
Precise measurement of the Decay K± ➞ π0 π0 µ± ν
Full text: pdf
Pre-published on: November 16, 2022
Published on:
Abstract
We report the first observation of the decay $K^{\pm} \rightarrow \pi^{0} \pi^{0} \mu^{\pm} \nu$ ($K^{00}_{\mu4}$)
by the NA48/2 experiment at the CERN SPS. From 2437 detected signal candidates with a S/B ratio of about 6,
the branching ratio of the decay is determined with high precision. In the region of squared dilepton mass
above $0.03$~GeV$^2/c^4$, the branching ratio is found to be $BR(K^{00}_{\mu 4},S_l>0.03) = (0.65 \pm 0.03) \times 10^{-6}$.
The full phase space result $BR(K^{00}_{\mu 4}) = (3.4 \pm 0.2) \times 10^{-6}$, depending on the decay model
extrapolation, is in a reasonable agreement with the R form factor prediction from 1-loop Chiral Perturbation Theory.
DOI: https://doi.org/10.22323/1.414.0723
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access