1999/02/22 by A. Alavi-Harati et. al, A. Alavi-Harati, I. F. M. Albuquerque +84 · 39 citations
Physics and Astronomy · #Branching fraction #High-Energy Particle Collisions Research #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #hep-ex
paper · pdf · doi:10.1103/physrevlett.83.917
published in Physical Review Letters 83(5), 917-921 (American Physical Society) · 5 pages, 4 figures
arxiv created 1999/02/22 · openalex publication_date 1999/08/02 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report on a new measurement of the decay KL\ensuremath→\ensuremathπ0\ensuremathγ\ensuremathγ by the KTeV experiment at Fermilab. We determine the KL\ensuremath→\ensuremathπ0\ensuremathγ\ensuremathγ branching ratio to be (1.68\ifmmode±\else\textpm\fi0.07\ifmmode±\else\textpm\fi0.08)\ifmmode×\else\texttimes\fi10^\ensuremath-6. Our data show the first evidence for a low-mass \ensuremathγ\ensuremathγ signal as predicted by recent O(p6) chiral perturbation calculations which include vector meson exchange contributions. From our data, we extract a value for the effective vector coupling aV\phantom\rule0ex0ex=\phantom\rule0ex0ex\ensuremath-0.72\ifmmode±\else\textpm\fi0.05\ifmmode±\else\textpm\fi0.06.