Search for B+ -> K+ nu nubar at Belle II using Graph Neural Networks

Sumitted to PubDB: 2024-09-05

Category: Master Thesis, Visibility: Public

Tags: -

Authors	Merna Abumusabh, Jacopo Cerasoli, Giulio Dujany
Date	Jan. 1, 2024
Belle II Number	BELLE2-MTHESIS-2024-021
Abstract	This 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.
Conference	Strasbourg