000002527 001__ 2527
000002527 005__ 20210701104404.0
000002527 037__ $$aBELLE2-MTHESIS-2021-065
000002527 041__ $$aeng
000002527 100__ $$aRobin Leboucher
000002527 245__ $$aTrack selection optimisation for τ studies at Belle II
000002527 260__ $$aMarseille, France$$bCentre de Physique des Particules de Marseille$$c2020
000002527 300__ $$a30
000002527 500__ $$aPresented on 01 07 2020
000002527 502__ $$aMSc$$bBesançon, France, Université de Franche-Comté$$c2020
000002527 520__ $$aBeing forbidden in the Standard Model, lepton flavour violating decays appears to be a good probe for searching physics beyond the standard model.  In particular, the tau lepton, thanks to its high mass enables more lepton flavour violating decays: τ→lγ and τ→3l with l=e,μ. In addition the interest for τ decays is reinforced by several new physics models prediction on branching fractions just below current experimental limits.The data taking of Belle II, located at KEK, Japan, started in 2019 and should end by 2027,collecting 50 times more data than its predecessor, Belle. The large amount of e+e− collisions will provide a huge number of τ+τ− pairs, ideal for tau studies.Theτ-group of Belle II needs differ from other B and C mesons analysis, in particular because of the signal contamination by beam backgrounds. The use of latest simulated samples and back-grounds implies the requirement to update the "good track" definition by optimizing the track selection on impact parameters.
000002527 700__ $$aJustine Serrano$$edir.
000002527 8560_ $$fleboucher@cppm.in2p3.fr
000002527 8564_ $$uhttps://docs.belle2.org/record/2527/files/BELLE2-MTHESIS-2021-065.pdf
000002527 980__ $$aTHESIS