A limit on the mass of the tau neutrino mντ is derived from 4.5 × 106 tau pairs produced in an integrated luminosity of 5.0 fb-1 of e+e- → γ * → τ+τ- reactions at center of mass energies ≈ 10.6 GeV. The measurement technique involves a two-dimensional extended likelihood analysis, including the dependence of the end-point population on mντ, and allows for the first time an explicit background contribution. We use the the decays τ → 5πντ and τ → 3π2π0ντ to obtain an upper limit of 30 MeV/c2 at 95% C.L.
|Original language||English (US)|
|Number of pages||10|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|State||Published - Jul 9 1998|
Bibliographical noteFunding Information:
We gratefully acknowledge the effort of the CESR staff in providing us with excellent luminosity and running conditions. J.R. Patterson and I.P.J. Shipsey thank the NYI program of the NSF, M. Selen thanks the PFF program of the NSF, M. Selen and H. Yamamoto thank the OJI program of DOE, J.R. Patterson, K. Honscheid, M. Selen and V. Sharma thank the A.P. Sloan Foundation, M. Selen thanks Research Corporation, S. von Dombrowski thanks the Swiss National Science Foundation, and H. Schwarthoff thanks the Alexander von Humboldt Stiftung for support. This work was supported by the National Science Foundation, the US Department of Energy, and the Natural Sciences and Engineering Research Council of Canada.
- Tau neutrino mass