Search for the flavor changing neutral current decay D0 ---> mu+ mu- with the HERA-B detector.

HERA-B COLLABORATION , H. WAHLBERG

PHYSICS LETTERS B

Año: 2004 vol. 96 p. 173 - 183

0370-2693

We report on a search for the flavor-changing neutral current decay $D^0 \to \mu^+\mu^-$ using $50 \times 10^6$ events recorded with a dimuon trigger in interactions of 920 GeV protons with nuclei by the HERA-B experiment. We find no evidence for such decays and set a 90% confidence level upper limit on the branching fraction $Br(D^0 \to \mu^+\mu^-) <2.0 \times 10^{-6}$.