An object-oriented tracking system for BaBar

Paper: 369
Session: A (talk)
Speaker: Schaffner, Stephen, Stanford Linear Accelerator Center, Stanford
Keywords: algorithms, C++, class libraries, object-oriented methods


An object-oriented tracking system for BaBar

Stephen Schaffner
Stanford Linear Accelerator Center
BaBar Collaboration

Abstract

The BaBar experiment at SLAC is using object-oriented software
for its off-line reconstruction; charged particle tracking software
is an integral part of this system. Object-orientation is intended
to provide us with flexible and maintainable tracking code. We
report on our current design for the core tracking system, describing
in detail the major abstractions (tracks, hits, trajectories) and
interfaces (to the track consumer, and to the detector description).
We also report on our experience with object-oriented programming
for charged particle vertexing and for kinematic fits at BaBar.
C++ permits a much more transparent implementation
of Kalman filter vertex fits. We have explored the use of classic
kinematic fitters, andtheir interface to the OO structure of the rest of
the reconstruction.Kinematic fits, combined with vertexing provides
good discrimination against combinatoric background.