https://doi.org/10.1140/epjc/s10052-014-3177-8
Special Article - Tools for Experiment and Theory
TauSpinner: a tool for simulating CP effects in
decays at LHC
1
The Faculty of Physics, Astronomy and Applied Computer Science, Jagiellonian University, Łojasiewicza 11, 30-348, Kraków, Poland
2
Institute of Physics, Jagiellonian University, Łojasiewicza 11, 30-348, Kraków, Poland
3
Institute of Nuclear Physics, PAN, Kraków, ul. Radzikowskiego 152, Kraków, Poland
* e-mail: Z.Was@cern.ch
Received:
19
October
2014
Accepted:
7
November
2014
Published online:
28
November
2014
In this paper, we discuss application of the TauSpinner package as a simulation tool for measuring the CP state of the newly discovered Higgs boson using the transverse spin correlations in the decay channel. We discuss application for its main background
as well. The TauSpinner package allows to add, with the help of weights, transverse spin correlations corresponding to any mixture of scalar/pseudoscalar state, on already existing events using information from the kinematics of outgoing
leptons and their decay products only. This procedure can be used when polarimetric vectors of the
s decays and density matrix for
-pair production are not stored with the event sample. We concentrate on the well-defined effects for the Higgs (or Higgs-like scalar) decays, which are physically separated from the production processes. TauSpinner also allows to reintroduce (or remove) spin correlations to events from Drell–Yan
process, the main background for the Higgs parity observables, again with the help of weights only. From the literature, we recall well-established observables, developed for measuring the CP of the Higgs, and use them as benchmarks for illustrating applications of the TauSpinner package. We also include a description of the code and prepared testing examples.
© SIF and Springer-Verlag Berlin Heidelberg, 2014