Download or read book Tau Decays Into Three Charged Leptons and Two Neutrinos written by and published by . This book was released on 2003 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have searched for the radiative leptonic tau decays? → eee−?{sub?}?{sub e} and? →?e+e−?{sub?}?{sub?} using 3.60 fb−1 of data collected by the CLEO-II experiment at CESR. We present a first observation of the? → ee+e−?{sub {tau}}?{sub e} process. For this channel we measure the branching fraction B({tau} → ee+e−?{sub {tau}}?{sub e}) = (2.8 ± 1.4 ± 0.4) x 10−5. An upper limit is established for the second channel: B({tau} → {mu}e+?{sub {tau}}?{sub {mu}})