000004505 001__ 4505
000004505 005__ 20240905101004.0
000004505 037__ $$aBELLE2-MTHESIS-2024-021
000004505 041__ $$aeng
000004505 100__ $$aMerna Abumusabh
000004505 245__ $$aSearch for B+ -> K+ nu nubar at Belle II using Graph Neural Networks
000004505 260__ $$aStrasbourg$$bIPHC$$c2024
000004505 300__ $$amult. p
000004505 500__ $$aPresented on 19 06 2024
000004505 502__ $$aMSc$$bStrasbourg, University of Strasbourg$$c2024
000004505 520__ $$aThis work presents the search for the decay of a charged B-meson into a charged kaon and a pair of neutrinos via graph-tagged analysis, which is an approach based on graph neural network,  in Belle~II, which is operating at the asymmetric electron-positron collider SuperKEKB located at KEK, Tsukuba, Japan.  B+ -> K+ nu nubar is a flavour changing neutral-current process that is highly suppressed in the Standard Model, and imposes many experimental challenge posed by the undetected pair of neutrinos in its final state. However, its branching fraction is accurately predicted in the Standard Model of particle physics, thus, a precise measurement of this branching fraction offers a unique opportunity to probe beyond Standard Model contributions. The expected upper limit on the branching fraction of B+ -> K+ nu nubar is determined to be 0.987* 10^{-5} at 90% confidence level, using simulated events.
000004505 700__ $$aGiulio DUJANY$$edir.
000004505 700__ $$aJacopo CERASOLI$$edir.
000004505 8560_ $$fmerna.abumusabh2@etu.unistra.fr
000004505 8564_ $$uhttps://docs.belle2.org/record/4505/files/BELLE2-MTHESIS-2024-021.pdf
000004505 980__ $$aTHESIS