| Thesis | |
| Report number | CERN-THESIS-2015-396 |
| Title | Measuring the decay $B^0 \rightarrow \pi^- D_s^+$ with sensitivity to the $b \rightarrow u$ quark transition |
| Author(s) | Mulder, Mick (Vrije U., Amsterdam) |
| Publication | 57. |
| Thesis note | Master : Vrije U., Amsterdam : 2015 |
| Thesis supervisor(s) | Bethlem, Rick ; Tuning, Niels ; Bel, Lennaert |
| Note | Presented 26 Jun 2015 |
| Subject category | Particle Physics - Experiment |
| Accelerator/Facility, Experiment | CERN LHC ; LHCb |
| Abstract | In this thesis, the measurement of $\mathcal{B}(B^0 \rightarrow \pi^- D_s^+)$ at LHCb is discussed. $B^0 \rightarrow \pi^- D_s^+$ is a non-leptonic tree decay, which only occurs via the $b \rightarrow u$ quark transition. As a result, it probes the CKM matrix element $|V_{ub}|$. As $B^0 \rightarrow \pi^- D_s^+$ is purely non-leptonic, non-factorisable contributions $|a_{NF}|$ from the strong interaction have to be taken into account. They are estimated using $B^0 \rightarrow D \bar{D}$ decays while taking non-tree (penguin, exchange and penguin annihilation) contributions into account. It is found that $\mathcal{B}(B^0 \rightarrow \pi^- D_s^+) = (26.7\pm 2.0(stat.)\pm 1.5(syst.)\pm1.6(\mathcal{B}))\times 10^{-6}$, which results in $|V_{ub}||a_{NF}| = (3.40\pm 0.14(\mathcal{B})\pm 0.29(ext.))10^{-3}$, where the first uncertainty comes from the measurement of $\mathcal{B}(B^0 \rightarrow \pi^- D_s^+)$ and the second uncertainty from external inputs. |
Email contact: amelie.caillet@cern.ch
Record created 2017-03-28, last modified 2017-04-18
