Skip to content

tauRecTools: deploy final combined TES and MVA TES calibrations

Bertrand Martin Dit Latour requested to merge martindl/athena:R22_MVATES_with0p_FINAL into master

Hello,

This MR is deploying the final Tau Energy Scale calibrations for combined TES (ATLTAU-1740) and MVA TES (ATLTAU-1739). The tunes were derived on Round 2.5 gamma* MC preproduction. It is mostly a resubmission of !45164 (closed) with a few extras: dedicated TES calibration for 0-prong taus, adjustment of tau pt cuts for ESD->AOD thinning.

For MVA TES, two small changes were made to the variable definitions.

  • First, ptDetectorAxis was replaced with the proper tau-vertex-corrected LC-scale tau pt, namely ptIntermediateAxis. These two pt calibrations are very close, but we should be using ptIntermediateAxis.
  • Second, for BDT scores that come out of the tau substructure reconstruction (BDTs that separate 1p0n/1p1n/1pXn and 3p0n/3pXn modes), something had been overlooked. The BDT scores are initialised to a default value of -1111 in the reconstruction, while the meaningful values set in the substructure reconstruction are within [-5,1]. So having a range that spans [-1111, 1] is quite bad for the MVA TES BRT optimisation, basically the cuts on these variable seemed completely random (TMVA probably scans for optimal cuts with a fixed step size). Scanning values in the meaningful range [-5-epsilon, 1] makes much more sense, although the BRT performance does not improve much.

In addition, a dedicated TES calibration is implemented for 0p taus. This gives a very slightly sharper turnon for 0p, compared to the inclusive MVA TES.

Finally, the tau pt cuts used in the tau thinning algorithm (ESD->AOD) were tuned to get approximately the same AOD size with the R22 approach (tau pt cut) and the R21 approach (seed jet pt cut), as motivated in these slides. That will result in a sizeable increase in AOD size compared to the current default pt cut of 10 GeV, which was derived with a R21 tune of MVA TES, and is overly aggressive in R22.

I'm also updating the digest counts, as tau energy calibration is known to impact the number of tracks in AODs, via tau track thinning.

Cheers, Bertrand

Edited by Bertrand Martin Dit Latour

Merge request reports