Reconstruction of high energy muons in the CMS experiment at the LHC
The detection of TeV muons is a fundamental ingredient of a number of key analyses performed by the CMS experiment at the LHC collider, like the search for new high-mass resonances decaying into di-muons or one muon and one neutrino. Muons with an energy of a few hundred GeV or more experience catastrophic energy losses in the material they traverse. These energy losses have a very significant negative imact on the most important parameters of the muon energy measurement distribution: central value, resolution, and tails.
In order to mitigate these effects, a new muon reconstruction algorithm, called DYnamic Truncation (DYT), has been developed. The DYT identifies the muon position measurements that are produced after a catastrophic energy loss. The inclusion of these measurements in the muon track fit is responsible for the degradation of the muon energy measurement. The identification of such measuremnts is based on the level of incompatibility between the position measurement itself and the expected position obtained using the previous measurements.
