Angular analysis of \(\Lambda_b^0 \rightarrow\Lambda \mu^+\mu^-\)and \(\Lambda _b^0\rightarrow J/\psi\Lambda\) decays with the LHCb detector

[摘要] In this thesis the angular analysis of \(\Lambda_b^0 \rightarrow\Lambda \mu^+\mu^-\)and \(\Lambda _b^0\rightarrow J/ \psi\Lambda\) decays is presented, using data from pp collisions recorded by the LHCb experiment between 2011 and 2016, corresponding to an integrated luminosity of approximately 5 fb\(^{-1}\). Forthe\(\Lambda_b^0 \rightarrow\Lambda \mu^+\mu^-\) decay, the angular observables are extracted at low hadronic-recoil using the method of moments. This is the first time that the complete set of the angular observables has been measured; the results are published in Ref. [1]. A measurement of the angular observables of the \(\Lambda_b^0 \rightarrow J/ \psi\Lambda\) decays is also performed. The angular observables are extracted using a moment analysis; an interpretation of the results in terms of the production polarisation of \(\Lambda_b^0\) and the decay amplitudes is also performed. This is the first time that the complete set of the angular observables of the \(\Lambda_b^0 \rightarrow J/ \psi\Lambda\) has been measured; the results are preliminary and correspond to the current status of the analysis.

[发布机构] University:University of Birmingham;Department:School of Physics and Astronomy

[关键词] Q Science;QC Physics