Year: 1987
Type: article
Abstract: We have measured the branching ratios for several \ensuremath{\tau} decay modes. We use ${e}^{+}$${e}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\ensuremath{\tau}}^{+}$${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$ events accumulated with the TPC/Two-Gamma facility at the SLAC ${e}^{+}$${e}^{\mathrm{\ensuremath{-}}}$ storage ring PEP. The data correspond to an integrated luminosity of 77 ${\mathrm{pb}}^{\mathrm{\ensuremath{-}}1}$ at a center-of-mass energy of 29 GeV. The one- and three-charged-particle inclusive branching ratios of the \ensuremath{\tau} decay are measured to be ${B}_{1}$=(84.7\ifmmode\pm\else\textpm\fi{}1.0)% and ${B}_{3}$=(15.1\ifmmode\pm\else\textpm\fi{}1.0)%, where ${B}_{1}$+${B}_{3}$ is constrained to be 99.85%. The branching ratios of the two leptonic decay modes are B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${e}^{\mathrm{\ensuremath{-}}}$ \ensuremath{\nu}${\ifmmode\bar\else\textasciimacron\fi{}}_{e}$${\ensuremath{\nu}}_{\ensuremath{\tau}}$)=(18.4\ifmmode\pm\else\textpm\fi{}1.6)% and B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\ensuremath{\mu}}^{\mathrm{\ensuremath{-}}}$ \ensuremath{\nu}${\ifmmode\bar\else\textasciimacron\fi{}}_{\ensuremath{\mu}}$${\ensuremath{\nu}}_{\ensuremath{\tau}}$)=(17.7\ifmmode\pm\else\textpm\fi{}1.4)%. If we then assume lepton universality, we obtain B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${e}^{\mathrm{\ensuremath{-}}}$ \ensuremath{\nu}${\ifmmode\bar\else\textasciimacron\fi{}}_{e}$${\ensuremath{\nu}}_{\ensuremath{\tau}}$)=(18.3\ifmmode\pm\else\textpm\fi{}0.9)% and B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\ensuremath{\mu}}^{\mathrm{\ensuremath{-}}}$ \ensuremath{\nu}${\ifmmode\bar\else\textasciimacron\fi{}}_{\ensuremath{\mu}}$${\ensuremath{\nu}}_{\ensuremath{\tau}}$)=(17.8\ifmmode\pm\else\textpm\fi{}0.9)%. We measure the Cabibbo-allowed semihadronic decay mode B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\ensuremath{\pi}}^{\mathrm{\ensuremath{-}}}$+neutral particles)=(47.0\ifmmode\pm\else\textpm\fi{}1.5)%, and the Cabibbo-suppressed \ensuremath{\tau} decay mode B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${K}^{\mathrm{\ensuremath{-}}}$+neutral particles)=(1.6\ifmmode\pm\else\textpm\fi{}0.4)%. By looking for associated photons, we find B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${K}^{\mathrm{\ensuremath{-}}}$${\ensuremath{\pi}}^{0}$+neutral particles) to be (1.2\ifmmode\pm\else\textpm\fi{}0.6)%. Using the channel K${\mathrm{*}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\mathit{K}}_{\mathit{S}}^{\mathit{O}}$${\mathrm{\ensuremath{\pi}}}^{+}$${\mathrm{\ensuremath{\pi}}}^{\mathrm{\ensuremath{-}}}$, we find B(${\ensuremath{\tau}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${K}^{\mathrm{*}\mathrm{\ensuremath{-}}}$(892)+neutral particles)=(1.4\ifmmode\pm\else\textpm\fi{}0.9)%. The quoted errors are the combined statistical and systematic errors.
Authors: H. Aihara, M. Alston-Garnjost, R. E. Avery, J. A. Bakken, A. Barbaro-Galtieri, A. R. Barker, A. V. Barnes, B. A. Barnett, B. A. Barnett, D. A. Bauer, H.-U. Bengtsson, D. L. Bintinger, G. J. Bobbink, T. S. Bolognese, A. D. Bross, C. D. Buchanan, A. Buijs, D. O. Caldwell, C-Y. Chien, A. R. Clark, G. D. Cowan, D. A. Crane, O. I. Dahl, K. A. Derby, J. J. Eastman, T. K. Edberg, P. H. Eberhard, A. M. Eisner, R. Enomoto, F. C. Erné, T. Fujii, J. W. Gary, W. Gorn, J. M. Hauptman, W. Hofmann, J. E. Huth, J. Hylen, T. Kamae, H. S. Kaye, K. H. Kees, R. W. Kenney, L. T. Kerth, Winston Ko, R. I. Koda, R. R. Kofler, K. K. Kwong, R. L. Lander, W. G. J. Langeveld, J. G. Layter, F. L. Linde, C. S. Lindsey, S. C. Loken, A. Lu, X-Q. Lu, G. R. Lynch, L. Madansky, R. J. Madaras, K. Maeshima, B. D. Magnuson, J. N. Marx, G. E. Masek, L. G. Mathis, J. A. J. Matthews, S. J. Maxfield, S. O. Melnikoff, E. S. Miller, W. Moses, R. R. McNeil, P. Nemethy, D. R. Nygren, P. J. Oddone, H. P. Paar, D. A. Park, S. K. Park, D. E. Pellett, A. Pevsner, M. Pripstein, M. T. Ronan, R. R. Ross, F. R. Rouse, K. A. Schwitkis, J. C. Sens, G. Shapiro, M. D. Shapiro, B. C. Shen, W. E. Slater, J. R. Smith, J. S. Steinman, M. L. Stevenson, D. H. Stork, M. G. Strauss, M. K. Sullivan, T. Takahashi, J. R. Thompson, N. Toge, S. Toutounchi, R. van Tyen, B. van Uitert, G. J. VanDalen, R. F. van Daalen Wetters, W. Vernon, W. Wagner, E. M. Wang, Y. X. Wang, M. R. Wayne, W. A. Wenzel, J. T. White, M. C. S. Williams, Z. R. Wolf, H. Yamamoto, S. J. Yellin, C. Zeitlin, W-M. Zhang
Language: English
Subfield: Nuclear and High Energy Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W1908307710