The Crystal Ball detector at the DORIS II storage ring at DESY has been used to measure the branching ratios for the decay modes τ±→h±π0ν and τ±→h±π0π 0ν, where h± is any charged hadron. The results are BR(τ±→h±π0 ν) = (22.0±0.8±1.9)%, BR(τ±→h±π0 π0ν) = (5.7±0.5+1.0-1.7)%. The first result is in good agreement with the present world average. The decay mode h±π0π0ν is reconstructed in τ decays for the first time. Its branching ratio, however, is somewhat lower than the corresponding world average, and therefore tends to increase the one-prong problem.
ASJC Scopus subject areas
- Nuclear and High Energy Physics