000002526 001__ 2526
000002526 005__ 20210701101733.0
000002526 037__ $$aBELLE2-MTHESIS-2021-064
000002526 041__ $$afre
000002526 100__ $$aGüney Polat
000002526 245__ $$aSearch for B -> K(*)νν decays in the Belle II experiment
000002526 260__ $$aStrasbourg$$bIPHC$$c2019
000002526 300__ $$amult. p
000002526 500__ $$aPresented on 21 06 2019
000002526 502__ $$aMSc$$bStrasbourg, Faculté de Physique et Ingénierie$$c2019
000002526 520__ $$aThe B -> K(*)νν decay channel, never discovered to this day, is actively sought in the Belle II experiment: its branching ratio is in the order of magnitude of 10^(−6) and could be significantly changed if new physics occurred in the decay process. During this internship, we analysed simulations of events produced inside the experiment’s collider SuperKEKB by electron-positron collisions. This analysis consists of the reconstruction of B mesons decays from simulations, in order to apply afterwards a selection optimised with the Punzi figure of merit and to retain only the events corresponding to the B0 → K(*0)νν channel, while rejecting the rest. Finally, we expect 0.9 ± 0.04 signal event and 1 ± 1 background event, for a luminosity of 1 ab^(−1). The efficiency of the signal selection procedure is (5.31 ± 0.27)%, without taking into account a first selection from the decay's reconstruction. An estimation of an upper limit on the branching ration still has to be done, with the help of statistical methods we need to study.
000002526 700__ $$aIsabelle Ripp-Baudot$$edir.
000002526 8560_ $$fpolat@cppm.in2p3.fr
000002526 8564_ $$uhttps://docs.belle2.org/record/2526/files/BELLE2-MTHESIS-2021-064.pdf
000002526 980__ $$aTHESIS