Consideration of Photon Radiation in Kinematic Fits for Future e+ e- Colliders
Abstract
Kinematic fitting is an important tool to improve the resolution in high-energy physics experiments. At future e+e- colliders, photon radiation parallel to the beam carrying away large amounts of energy and momentum will become a challenge for kinematic fitting. A photon with longitudinal momentum pz({\eta}) is introduced, which is parametrized such that {\eta} follows a normal distribution. In the fit, {\eta} is treated as having a measured value of zero, which corresponds to pz = 0. As a result, fits with constraints on energy and momentum conservation converge well even in the presence of a highly energetic photon, while the resolution of fits without such a photon is retained. A fully simulated and reconstructed e+e- -> qqqq event sample at sqrt(s) = 500 GeV is used to investigate the performance of this method under realistic conditions, as expected at the International Linear Collider.
Cite
@article{arxiv.1007.0020,
title = {Consideration of Photon Radiation in Kinematic Fits for Future e+ e- Colliders},
author = {Moritz Beckmann and Benno List and Jenny List},
journal= {arXiv preprint arXiv:1007.0020},
year = {2010}
}
Comments
7 pages, 4 figures, conference proceeding of International Linear Collider Workshop 2010, Beijing