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Draft: Adapt SimpleCone algorithm simulation to the data formats and interfaces of the Phase-1 L1Calo system

Johannes Frederic Damp requested to merge jodamp/athena:fix-simple-cone-phase-1 into 23.0

edit: Will upload ref file changes into a new MR - jmharris

Currently firmware and simulation of the Phase-1 L1Topo system show mismatches for the SimpleCone algorithm.

From a recently investigated subset of events, all of the mismatches could be explained by two reasons:

  1. The DeltaR^2 calculation does not use the bitwise function calcDeltaR2BW that is used in most other algorithms, instead DeltaR^2 is calculated manually. In addition, a conversion factor of 100 is applied when checking the DeltaR^2 criterion, which is related to Phase-0 eta/phi granularity, but yields wrong results for the Phase-1 system. The calcDeltaR2BW takes care of all granularity conversions and differences between Phase-0 and Phase-1 L1Topo.

  2. The simulation implementation sets default values for a minEta and a maxEta cut, however minEta and maxEta cuts do neither exist in the firmware nor are specified in the menu (compare e.g. https://gitlab.cern.ch/atlas/athena/-/blob/master/Trigger/TriggerCommon/TriggerMenuMT/python/L1/Config/TopoAlgoDef.py#L985 for a list of menu parameters for this algorithm) In simulation, since the parameter does not exist in the menu, a default value of 31 is currently used, which however is not converted to phase-1 granularity, leading to an effective maxEta cutoff at 31/40=0.775, rejecting most of the jets.

With this MR, the two problems are solved as follows:

  1. Use calcDeltaR2BW to calculate DeltaR^2 between jet pairs
  2. Remove all references to minEta and maxEta
Edited by Jack Harrison

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