A study of single photon production in e+e− collisions at s=58 GeV with the TOPAZ detector at TRISTAN

We report a study of single photon production in e+e− collisions at s=58 GeV with the TOPAZ detector at TRISTAN. From data corresponding to an integrated luminosity of 213 pb−1, 5 single photon candidates remained after event selection, which can be compared with the expected 3.1 ννγ and 2.8 background events. These results exclude the selectron mass below 47.2 GeV at the 90% confidence level, if ẽL and ẽR are mass-degenerate and the photino is massless. When combined with results from other experiments, this limit improves to 75.0 GeV.