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Search for the KL-->pi 0 pi 0 e+e- decay in the KTeV experiment
A Alavi-Harati1, T Alexopoulos, M Arenton
1University of Wisconsin, Madison, Wisconsin 53706, USA.
Physical Review Letters
|November 22, 2002
Summary
Researchers searched for the KL-->pi 0 pi 0 e+e- decay mode following a CP violating asymmetry discovery. One candidate event was observed, setting an upper limit on the branching ratio.
Area of Science:
- Particle Physics
- High Energy Physics
- Kaon Decays
Background:
- A significant CP violating asymmetry was recently observed in the KL-->pi+pi-e+e- decay mode.
- This discovery necessitates further investigation into related decay channels to understand CP violation mechanisms.
Purpose of the Study:
- To search for the rare KL-->pi 0 pi 0 e+e- decay mode.
- To establish an upper limit for the branching ratio of this decay mode.
Main Methods:
- Analysis of data from the KTeV-E799 experiment at Fermilab.
- Examined a sample of 2.7 x 10^11 neutral kaon (KL) decays.
- Event selection and background estimation for the KL-->pi 0 pi 0 e+e- channel.
Main Results:
- One candidate event for the KL-->pi 0 pi 0 e+e- decay was observed.
- The expected background for this channel was estimated to be 0.3 events.
- An upper limit for the KL-->pi 0 pi 0 e+e- branching ratio was set at 6.6 x 10^-9 at the 90% confidence level.
Conclusions:
- The study provides a stringent upper limit on the branching ratio of the KL-->pi 0 pi 0 e+e- decay.
- This result contributes to the ongoing investigation of CP violation in kaon decays and particle physics.
- Further experimental and theoretical work may be needed to fully interpret these findings.
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