tauRec: drop TauCommonPi0Cells container from xAOD

Hello,

This MR is dropping the TauCommonPi0Cells container, it is too large to afford it in xAODs (it was not written out in R21 xAODs). We will write it out on demand for performance samples. Note to ourselves: this means we can no longer rerun our custom topoclustering at xAOD level, so we need to double check it is well configured in R22: https://gitlab.cern.ch/atlas/athena/blob/master/Reconstruction/tauRec/share/Pi0ClusterMaker_jobOptions.py

Bright side: we save about 20 kb per event!!

Cheers, Bertrand

Reconstruction/tauRec/python/TauRecBuilder.py

@@ -23,12 +23,11 @@ import traceback
 from RecExConfig.Configured import Configured
 from .TauRecConfigured import TauRecConfigured
 
-# global tauRec config keys
+# global tauRec config keys - to be replaced with tauRecFlags
 _outputType = "xAOD::TauJetContainer"
 _outputKey = "TauJets"
 _outputAuxType = "xAOD::TauJetAuxContainer"
 _outputAuxKey = "TauJetsAux."
-_track_collection = "InDetTrackParticles"
 
 ################################################################################
 ## @class TauRecCoreBuilder
@@ -40,14 +39,19 @@ class TauRecCoreBuilder ( TauRecConfigured ) :
     Find clusters used for Pi0 identification and eflow variables.
     PhotonConversion will be run here too.
     """
-  
+    
     _output     = { _outputType:_outputKey , _outputAuxType:_outputAuxKey,
                     'xAOD::TauTrackContainer' : 'TauTracks',
                     'xAOD::CaloClusterContainer' : 'TauShotClusters',
                     'xAOD::PFOContainer' : 'TauShotParticleFlowObjects',
                     'CaloCellContainer' : 'TauCommonPi0Cells',
                     }
-    
+
+    # drop TauCommonPi0Cells container from nominal xAODs, too heavy
+    _outputAOD = _output.copy()
+    _outputAOD.pop('CaloCellContainer')
+
+
     def __init__(self, name = "TauCoreBuilder",doPi0Clus=False, doTJVA=False):
         self.name = name
         self.doPi0Clus = doPi0Clus
@@ -65,7 +69,7 @@ class TauRecCoreBuilder ( TauRecConfigured ) :
         
         from RecExConfig.ObjKeyStore import objKeyStore
         objKeyStore.addManyTypesStreamESD(self._output)
-        objKeyStore.addManyTypesStreamAOD(self._output)              
+        objKeyStore.addManyTypesStreamAOD(self._outputAOD)              
         objKeyStore.addManyTypesTransient(self._output)              
         
         import tauRec.TauAlgorithmsHolder as taualgs