Search for B0 → τ+τ− at Belle
| Autor: | Chia-Hao Tu, 涂嘉豪 |
|---|---|
| Rok vydání: | 2016 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 104 We perform a search for B0->τ+τ−, based on a data sample of 772 million BB pairs collected at the (4S) resonance with the Belle detector at the KEKB asymmetric-energy e−e+ collider. We consider three τ decay modes ( τ->e,μ,π), which corresponds to six sub-decay final states of B. Since there are 2~4 neutrinos in the final state for signals, we employ the hadronic tagging method to fully reconstruct the accompanying B mesons. The signal and background separation is achieved using the NeuroBaye package with various kinematic variables. No significant signal is found, and we estimate the upper limit of branching fraction at 90% confidence level: B(B0->τ+τ−) < 1.56 × 10E−3. So far the obtained upper limit is the most stringent. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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