Speaker
Christian Pulvermacher
(KIT)
Description
Belle II is an experiment being built at the $e^+e^-$ SuperKEKB B factory, and will record decays of a large number of $B \bar B$ pairs.
This pairwise production of $B$ mesons allows analysts to use one correctly reconstructed $B$ meson to deduce the four-momentum and flavour of the other (signal-side) $B$ meson, without reconstructing any of its daughter particles.
It also permits, in conjunction with a signal-side selection, to account for all tracks and calorimeter signals in an event and thus get a cleaner sample, e.g. for decays containing neutrinos.
I will present a software framework for Belle II that reconstructs $B$ mesons in many decay modes with minimal user intervention.
It does so by reconstructing particles in user-supplied decay channels, and then in turn using these reconstructed particles in higher-level decays.
This hierarchical reconstruction allows to cover a relatively high fraction of all $B$ decays by specifying a limited number of particle decays.
Multivariate classification methods are used to achieve a high signal-to-background ratio in each individual channel.
The entire reconstruction, including the application of precuts and classifier trainings, is automated to a high degree and will allow users to easily add new channels or to retrain on analysis-specific Monte Carlo samples.
Authors
Christian Pulvermacher
(KIT)
Thomas Keck
(KIT)
Co-authors
Martin Heck
(KIT, Karlsruhe)
Michael Feindt
(KIT)
Thomas Kuhr
(KIT)
