We search for lepton-flavor and lepton-number-violating. Τ decays into a lepton (ℓ= electron or muon) and two charged mesons (h,h'=π± or K±) using 854 fb-1 of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. We obtain 90% confidence level upper limits on the. Τ→ℓhh' branching fractions in the range. (2.0-8.4)×10-8. These results improve upon our previously published upper limits by factors of about 1.8 on average.
|Number of pages||8|
|Journal||Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics|
|Publication status||Published - 2013 Feb 26|
Bibliographical noteFunding Information:
We thank the KEKB group for the excellent operation of the accelerator; the KEK cryogenics group for the efficient operation of the solenoid; and the KEK computer group, the National Institute of Informatics, and the PNNL/EMSL computing group for valuable computing and SINET4 network support. We acknowledge support from the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan, the Japan Society for the Promotion of Science (JSPS) , and the Tau-Lepton Physics Research Center of Nagoya University ; the Australian Research Council and the Australian Department of Industry, Innovation, Science and Research ; the National Natural Science Foundation of China under contract Nos. 10575109 , 10775142 , 10875115 and 10825524 ; the Ministry of Education, Youth and Sports of the Czech Republic under contract Nos. LA10033 and MSM0021620859 ; the Department of Science and Technology of India ; the Istituto Nazionale di Fisica Nucleare of Italy ; the BK21 and WCU program of the Ministry Education Science and Technology, National Research Foundation of Korea , and GSDC of the Korea Institute of Science and Technology Information ; the Polish Ministry of Science and Higher Education ; the Ministry of Education and Science of the Russian Federation and the Russian Federal Agency for Atomic Energy and a Grant of the Russian Foundation for Basic Research 12-02-01032 ; the Slovenian Research Agency ; the Swiss National Science Foundation ; the National Science Council and the Ministry of Education of Taiwan ; and the U.S. Department of Energy and the National Science Foundation . This work is supported by a Grant-in-Aid from MEXT for Science Research in a Priority Area (“New Development of Flavor Physics”), and from JSPS for Creative Scientific Research (“Evolution of Tau-lepton Physics”).
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics