Published August 24, 2007 | Version v1
Journal article Metadata-only

First Observation of KL→π±e±νe+e-

Creators

  • 1. Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637 (United States)
  • 2. Department of Physics and Institute of Nuclear and Particle Physics, University of Virginia, Charlottesville, Virginia 22901 (United States)
  • 3. University of Colorado, Boulder, Colorado 80309 (United States)

Description

This Letter is the first report of the KL→π±e±νe+e- decay. Based on 19 208±144 events, we determine the branching fraction, B(KL→π±e±νe+e-;Me+e->5 MeV/c2,Ee+e-*>30 MeV)=(1.285±0.041)x10-5, and Γ(Ke3ee;Me+e->5 MeV/c2)/Γ(Ke3)=[4.57±0.04(stat)±0.14(syst)]x10-5. This ratio agrees with a theoretical prediction based on chiral perturbation theory (ChPT) calculated to O(p4). The measured kinematical distributions agree with those predicted by just ChPT O(p4), but show significant disagreement with ones predicted by leading-order ChPT

Additional details

Identifiers

DOI
10.1103/PhysRevLett.99.081803;

Publishing Information

Journal Title
Physical Review Letters
Journal Volume
99
Journal Issue
8
Journal Page Range
p. 081803-081803.5
ISSN
0031-9007
CODEN
PRLTAO

INIS

Country of Publication
United States
Country of Input or Organization
International Atomic Energy Agency (IAEA)
INIS RN
39050073
Subject category
S72: PHYSICS OF ELEMENTARY PARTICLES AND FIELDS;
Descriptors DEI
BRANCHING RATIO; CHIRALITY; ELECTRONS; KAONS NEUTRAL LONG-LIVED; MEV RANGE 10-100; PARTICLE DECAY; PARTICLE PRODUCTION; PERTURBATION THEORY; PIONS MINUS; POSITRONS; SCORPIONS
Descriptors DEC
ANIMALS; ANTILEPTONS; ANTIMATTER; ANTIPARTICLES; ARACHNIDS; ARTHROPODS; BOSONS; DECAY; DIMENSIONLESS NUMBERS; ELEMENTARY PARTICLES; ENERGY RANGE; FERMIONS; HADRONS; INVERTEBRATES; KAONS; KAONS NEUTRAL; LEPTONS; MATTER; MESONS; MEV RANGE; PARTICLE PROPERTIES; PIONS; PSEUDOSCALAR MESONS; STRANGE MESONS; STRANGE PARTICLES

Optional Information

Notes
(c) 2007 The American Physical Society
Collaborations
KTeV Collaboration