Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published June 1, 2006 | Published
Journal Article Open

Search for the decay τ-→3π^-2π^+2π^0ν_τ


A search for the decay of the τ lepton to five charged and two neutral pions is performed using data collected by the BABAR detector at the PEP-II asymmetric-energy e^+e^- collider. The analysis uses 232  fb^(-1) of data at center-of-mass energies on or near the Υ(4S) resonance. We observe 10 events with an expected background of 6.5_(-1.4)^(+2.0) events. In the absence of a signal, we set the limit on the branching ratio B(τ-→3π^-2π^+2π^0ν_τ)<3.4×10^(-6) at the 90% confidence level. This is a significant improvement over the previously established limit. In addition, we search for the decay mode τ-→2ωπ-ν_τ. We observe 1 event with an expected background of 0.4+1.0/-0.4 events and calculate the upper limit B(τ-→2ωπ-ν_τ)<5.4×10^(-7) at the 90% confidence level. This is the first upper limit for this mode.

Additional Information

© 2006 The American Physical Society. Received 7 April 2006; published 9 June 2006. We are grateful for the extraordinary contributions of our PEP-II colleagues in achieving the excellent luminosity and machine conditions that have made this work possible. The success of this project also relies critically on the expertise and dedication of the computing organizations that support BABAR. The collaborating institutions wish to thank SLAC for its support and the kind hospitality extended to them. This work is supported by the US Department of Energy and National Science Foundation, the Natural Sciences and Engineering Research Council (Canada), Institute of High Energy Physics (China), the Commissariat à l'Energie Atomique and Institut National de Physique Nucléaire et de Physique des Particules (France), the Bundesministerium für Bildung und Forschung and Deutsche Forschungsgemeinschaft (Germany), the Istituto Nazionale di Fisica Nucleare (Italy), the Foundation for Fundamental Research on Matter (The Netherlands), the Research Council of Norway, the Ministry of Science and Technology of the Russian Federation, and the Particle Physics and Astronomy Research Council (United Kingdom). Individuals have received support from CONACyT (Mexico), the Marie-Curie IEF (European Union), the A. P. Sloan Foundation, the Research Corporation, and the Alexander von Humboldt Foundation.

Attached Files

Published - AUBprd06p.pdf


Files (222.4 kB)
Name Size Download all
222.4 kB Preview Download

Additional details

August 19, 2023
October 23, 2023