Public Member Functions | |
NPVBeamspotCorrection () | |
void | initNPVBeamspotCorrection () |
double | GetNVertexBsCorrection (double nRecoVtx) |
NPVBeamspotCorrection::NPVBeamspotCorrection | ( | ) |
Return approximate correction on the number of reconstructed vertices due to different beamspot longitudinal lengths.
Author: S. Pagan Griso <spagangriso@lbl.gov> Adapted for ApplyJetCalibration/JetCalibTools by Joe Taenzer <joseph.taenzer@cern.ch>
Description: Use GetNVertexBsCorrected(...) to get the corrected number of vertices expected on average with a beamspot length of 47mm, assuming your input value refers to a sample with beamspot length of 66mm (MC12a).
Disclaimer: The following is based on a statistical extrapolation based on low-mu data. This is meant to give a feeling of the magnitude of the effect on average. This function can be used as a "x-axis" scaling in order to see the magnitude of the effect on quantities depending on the number of vertices, or to roughly estimate if the residual discrepancy observed in the number of reconstructed vertices after a <mu> re-weighting is consistent with this effect.
Other notes: If you are in need to get the correction for different beamspot sizes, please just get in contact with me and I can easily provide you with a more comphrensive set of simple tools to do that.