Experimental search for the decay mode K_L -> pi^0 gamma e^+ e^-

TL;DR

This paper reports the first experimental search for the decay K_L -> pi^0 gamma e^+ e^-, setting an upper limit on its branching ratio due to no observed events, contributing new data to rare kaon decay studies.

Contribution

It provides the first experimental upper limit on the branching ratio of the decay K_L -> pi^0 gamma e^+ e^- with no prior measurements.

Findings

No events observed in the decay channel.

Set a 90% confidence level upper limit of 7.1x10^{-7} on the branching ratio.

First published experimental result for this decay mode.

Abstract

We report on results of a search for the decay mode K_L -> pi^0 gamma e^+ e^- conducted by the E162 experiment at KEK. We observed no events and set a 90% confidence level upper limit of Br(K_L -> pi^0 gamma e^+ e^-)< 7.1x10^{-7} for its branching ratio. This is the first published experimental result on this decay mode.