The Belle II experiment is designed to produce many B mesons. Due to their heavy mass, they decay immediately after production into several daughter particles that subsequently can decay further.
Today we want to learn how to reconstruct mother particle properties (in this case: the mass) from its decay products. We will use the drag-and-drop histogramm builder which enables to combine particles. Their invariant mass is shown. If the selected particles were actually produced by the same mother, the invariant mass peaks at the mother’s mass.
Following the excercises, step by step we will reconstruct heavier particles until we are finally able to reconstruct the core ingredient of the Belle II experiment: A B meson.
The analysis can be started here.