Observation of [formula presented]
A Ishikawa, K Abe, K Abe, T Abe, I Adachi, BS Ahn, H Aihara, K Akai, M Akatsu, M Akemoto, Y Asano, T Aso, V Aulchenko, T Aushev, AM Bakich, Y Ban, A Bay, I Bizjak, A Bondar, A Bozek Show all
Physical Review Letters | Published : 2003
We report the observation of the flavor-changing neutral current decay [Formula presented] and an improved measurement of the decay [Formula presented], where [Formula presented] represents an electron or a muon, with a data sample of [Formula presented] accumulated at the [Formula presented] resonance with the Belle detector at KEKB. The results for the branching fractions are [Formula Presented] and [Formula Presented], where the first error is statistical, the second is systematic and the third is from model dependence. © 2003 The American Physical Society.