Streamline HLT L3 Muon reconstruction

- execute either Inside-Out or Outside-In reconstruction first, resorting to the second pass only for candidates that require it
- Tracks filtered by quality using some of the same criteria as HLT Muon ID
- L1/L2 objects matched with bad L3 tracks are reused to seed the second reconstruction step
- Changes implemented via 2 procModifiers for IO first (default) and OI first reconstruction
- Implemented changes in SingleMu, TTbar, and ZMM workflows with .777 and .778 subfixes for IO and OI first reconstruction, respectively
- Change 2026 to Run4 in Phase 2 workflows

Configuration/ProcessModifiers/python/phase2L3MuonsOIFirst_cff.py

@@ -0,0 +1,4 @@
+import FWCore.ParameterSet.Config as cms
+
+# this modifier is for enabling Phase 2 L3 Tracker Muon Outside-In first reconstruction 
+phase2L3MuonsOIFirst = cms.Modifier()

Configuration/PyReleaseValidation/python/upgradeWorkflowComponents.py

@@ -814,6 +814,70 @@ def condition(self, fragment, stepList, key, hasHarvest):
 upgradeWFs['ticl_v5_superclustering_mustache_pf'].step3 = {'--procModifiers': 'ticl_v5,ticl_superclustering_mustache_pf'}
 upgradeWFs['ticl_v5_superclustering_mustache_pf'].step4 = {'--procModifiers': 'ticl_v5,ticl_superclustering_mustache_pf'}
 
+# Improved L2 seeding from L1Tk Muons and L3 Tracker Muon Inside-Out reconstruction first (Phase-2 Muon default)
+class UpgradeWorkflow_phase2L2AndL3Muons(UpgradeWorkflow):
+    def setup_(self, step, stepName, stepDict, k, properties):
+        if ('Digi' in step and 'NoHLT' not in step) or ('HLTOnly' in step):
+            stepDict[stepName][k] = merge([self.step2, stepDict[step][k]])
+        if 'RecoGlobal' in step:
+            stepDict[stepName][k] = merge([self.step3, stepDict[step][k]])
+        if 'HARVESTGlobal' in step:
+            stepDict[stepName][k] = merge([self.step4, stepDict[step][k]])
+    def condition(self, fragment, stepList, key, hasHarvest):
+        return (fragment=="ZMM_14" or 'SingleMu' in fragment or 'TTbar_14' in fragment) and 'Run4' in key
+
+upgradeWFs['phase2L2AndL3Muons'] = UpgradeWorkflow_phase2L2AndL3Muons(
+    steps = [
+        'HLTOnly',
+        'DigiTrigger',
+        'RecoGlobal',
+        'HARVESTGlobal'
+    ],
+    PU = [
+        'HLTOnly',
+        'DigiTrigger',
+        'RecoGlobal',
+        'HARVESTGlobal'
+    ],
+    suffix = '_phase2L2AndL3MuonsIOFirst',
+    offset = 0.777,
+)
+upgradeWFs['phase2L2AndL3Muons'].step2 = {'--procModifiers':'phase2L2AndL3Muons'}
+upgradeWFs['phase2L2AndL3Muons'].step3 = {'--procModifiers':'phase2L2AndL3Muons'}
+upgradeWFs['phase2L2AndL3Muons'].step4 = {'--procModifiers':'phase2L2AndL3Muons'}
+
+# Improved L2 seeding from L1Tk Muons and L3 Tracker Muon Outside-In reconstruction first
+class UpgradeWorkflow_phase2L3MuonsOIFirst(UpgradeWorkflow):
+    def setup_(self, step, stepName, stepDict, k, properties):
+        if ('Digi' in step and 'NoHLT' not in step) or ('HLTOnly' in step):
+            stepDict[stepName][k] = merge([self.step2, stepDict[step][k]])
+        if 'RecoGlobal' in step:
+            stepDict[stepName][k] = merge([self.step3, stepDict[step][k]])
+        if 'HARVESTGlobal' in step:
+            stepDict[stepName][k] = merge([self.step4, stepDict[step][k]])
+    def condition(self, fragment, stepList, key, hasHarvest):
+        return (fragment=="ZMM_14" or 'SingleMu' in fragment or 'TTbar_14' in fragment) and 'Run4' in key
+
+upgradeWFs['phase2L3MuonsOIFirst'] = UpgradeWorkflow_phase2L3MuonsOIFirst(
+    steps = [
+        'HLTOnly',
+        'DigiTrigger',
+        'RecoGlobal',
+        'HARVESTGlobal'
+    ],
+    PU = [
+        'HLTOnly',
+        'DigiTrigger',
+        'RecoGlobal',
+        'HARVESTGlobal'
+    ],
+    suffix = '_phase2L2AndL3MuonsOIFirst',
+    offset = 0.778,
+)
+upgradeWFs['phase2L3MuonsOIFirst'].step2 = {'--procModifiers':'phase2L2AndL3Muons,phase2L3MuonsOIFirst'}
+upgradeWFs['phase2L3MuonsOIFirst'].step3 = {'--procModifiers':'phase2L2AndL3Muons,phase2L3MuonsOIFirst'}
+upgradeWFs['phase2L3MuonsOIFirst'].step4 = {'--procModifiers':'phase2L2AndL3Muons,phase2L3MuonsOIFirst'}
+
 # Track DNN workflows
 class UpgradeWorkflow_trackdnn(UpgradeWorkflow):
     def setup_(self, step, stepName, stepDict, k, properties):

HLTrigger/Configuration/python/HLT_75e33/modules/hltIter2Phase2L3FromL1TkMuonPixelSeedsFiltered_cfi.py

@@ -33,3 +33,10 @@
     nSeedsMax_E = cms.int32(20),
     src = cms.InputTag("hltIter2Phase2L3FromL1TkMuonPixelSeeds")
 )
+
+from Configuration.ProcessModifiers.phase2L2AndL3Muons_cff import phase2L2AndL3Muons
+from Configuration.ProcessModifiers.phase2L3MuonsOIFirst_cff import phase2L3MuonsOIFirst
+(phase2L2AndL3Muons & phase2L3MuonsOIFirst).toModify(
+    hltIter2Phase2L3FromL1TkMuonPixelSeedsFiltered, 
+    L1TkMu = "hltPhase2L3MuonFilter:L1TkMuToReuse"
+)

HLTrigger/Configuration/python/HLT_75e33/modules/hltPhase2L3FromL1TkMuonPixelTracksTrackingRegions_cfi.py

@@ -22,3 +22,10 @@
         zErrorVetex = cms.double(0.2)
     )
 )
+
+from Configuration.ProcessModifiers.phase2L2AndL3Muons_cff import phase2L2AndL3Muons
+from Configuration.ProcessModifiers.phase2L3MuonsOIFirst_cff import phase2L3MuonsOIFirst
+(phase2L2AndL3Muons & phase2L3MuonsOIFirst).toModify(
+    hltPhase2L3FromL1TkMuonPixelTracksTrackingRegions.RegionPSet,
+    input = "hltPhase2L3MuonFilter:L1TkMuToReuse"
+)

HLTrigger/Configuration/python/HLT_75e33/modules/hltPhase2L3MuonFilter_cfi.py

@@ -0,0 +1,24 @@
+import FWCore.ParameterSet.Config as cms
+
+hltPhase2L3MuonFilter = cms.EDProducer("phase2HLTMuonSelectorForL3",
+    l1TkMuons = cms.InputTag("l1tTkMuonsGmt"),
+    l2MuonsUpdVtx = cms.InputTag("hltL2MuonsFromL1TkMuon:UpdatedAtVtx"),
+    l3Tracks = cms.InputTag("hltIter2Phase2L3FromL1TkMuonMerged"),
+    IOFirst = cms.bool(True),
+    matchingDr = cms.double(0.02),
+    applyL3Filters = cms.bool(True),
+    MinNhits = cms.int32(1),
+    MaxNormalizedChi2 = cms.double(5.0),
+    MinNhitsMuons = cms.int32(0),
+    MinNhitsPixel = cms.int32(1),
+    MinNhitsTracker = cms.int32(6),
+    MaxPtDifference = cms.double(999.0),
+)
+
+from Configuration.ProcessModifiers.phase2L2AndL3Muons_cff import phase2L2AndL3Muons
+from Configuration.ProcessModifiers.phase2L3MuonsOIFirst_cff import phase2L3MuonsOIFirst
+(phase2L2AndL3Muons & phase2L3MuonsOIFirst).toModify(
+    hltPhase2L3MuonFilter,
+    l3Tracks = "hltPhase2L3OIMuonTrackSelectionHighPurity",
+    IOFirst = False,
+)

HLTrigger/Configuration/python/HLT_75e33/modules/hltPhase2L3MuonMerged_cfi.py

@@ -8,18 +8,47 @@
     MinFound = cms.int32(3),
     MinPT = cms.double(0.05),
     ShareFrac = cms.double(0.19),
-    TrackProducers = cms.VInputTag("hltPhase2L3OIMuonTrackSelectionHighPurity", "hltIter2Phase2L3FromL1TkMuonMerged"),
+    TrackProducers = cms.VInputTag(
+        "hltPhase2L3OIMuonTrackSelectionHighPurity",
+        "hltIter2Phase2L3FromL1TkMuonMerged",
+    ),
     allowFirstHitShare = cms.bool(True),
     copyExtras = cms.untracked.bool(True),
     copyMVA = cms.bool(False),
     hasSelector = cms.vint32(0, 0),
     indivShareFrac = cms.vdouble(1.0, 1.0),
-    newQuality = cms.string('confirmed'),
-    selectedTrackQuals = cms.VInputTag("hltPhase2L3OIMuonTrackSelectionHighPurity", "hltIter2Phase2L3FromL1TkMuonMerged"),
-    setsToMerge = cms.VPSet(cms.PSet(
-        pQual = cms.bool(False),
-        tLists = cms.vint32(0, 1)
-    )),
-    trackAlgoPriorityOrder = cms.string('hltESPTrackAlgoPriorityOrder'),
-    writeOnlyTrkQuals = cms.bool(False)
+    newQuality = cms.string("confirmed"),
+    selectedTrackQuals = cms.VInputTag(
+        "hltPhase2L3OIMuonTrackSelectionHighPurity",
+        "hltIter2Phase2L3FromL1TkMuonMerged",
+    ),
+    setsToMerge = cms.VPSet(cms.PSet(pQual = cms.bool(False), tLists = cms.vint32(0, 1))),
+    trackAlgoPriorityOrder = cms.string("hltESPTrackAlgoPriorityOrder"),
+    writeOnlyTrkQuals = cms.bool(False),
+)
+
+from Configuration.ProcessModifiers.phase2L2AndL3Muons_cff import phase2L2AndL3Muons
+phase2L2AndL3Muons.toModify(
+    hltPhase2L3MuonMerged,
+    TrackProducers = cms.VInputTag(
+        "hltPhase2L3OIMuonTrackSelectionHighPurity",
+        "hltPhase2L3MuonFilter:L3IOTracksFiltered",
+    ),
+    selectedTrackQuals = cms.VInputTag(
+        "hltPhase2L3OIMuonTrackSelectionHighPurity",
+        "hltPhase2L3MuonFilter:L3IOTracksFiltered",
+    ),
+)
+
+from Configuration.ProcessModifiers.phase2L3MuonsOIFirst_cff import phase2L3MuonsOIFirst
+(phase2L2AndL3Muons & phase2L3MuonsOIFirst).toModify(
+    hltPhase2L3MuonMerged,
+    TrackProducers = cms.VInputTag(
+        "hltPhase2L3MuonFilter:L3OITracksFiltered",
+        "hltIter2Phase2L3FromL1TkMuonMerged",
+    ),
+    selectedTrackQuals = cms.VInputTag(
+        "hltPhase2L3MuonFilter:L3OITracksFiltered",
+        "hltIter2Phase2L3FromL1TkMuonMerged",
+    ),
 )

HLTrigger/Configuration/python/HLT_75e33/modules/hltPhase2L3OISeedsFromL2Muons_cfi.py

@@ -39,3 +39,15 @@
     tsosDiff1 = cms.double(0.2),
     tsosDiff2 = cms.double(0.02)
 )
+
+from Configuration.ProcessModifiers.phase2L2AndL3Muons_cff import phase2L2AndL3Muons
+phase2L2AndL3Muons.toModify(
+    hltPhase2L3OISeedsFromL2Muons,
+    src = "hltPhase2L3MuonFilter:L2MuToReuse"
+)
+
+from Configuration.ProcessModifiers.phase2L3MuonsOIFirst_cff import phase2L3MuonsOIFirst
+(phase2L2AndL3Muons & phase2L3MuonsOIFirst).toModify(
+    hltPhase2L3OISeedsFromL2Muons,
+    src ="hltL2MuonsFromL1TkMuon:UpdatedAtVtx"
+)

HLTrigger/Configuration/python/HLT_75e33/sequences/HLTMuonsSequence_cfi.py

@@ -7,4 +7,44 @@
 from ..sequences.HLTPhase2L3MuonsSequence_cfi import *
 from ..sequences.HLTPhase2L3OISequence_cfi import *
 
-HLTMuonsSequence = cms.Sequence(HLTL2MuonsFromL1TkSequence+HLTPhase2L3OISequence+HLTPhase2L3FromL1TkSequence+HLTIter0Phase2L3FromL1TkSequence+HLTIter2Phase2L3FromL1TkSequence+HLTPhase2L3MuonsSequence)
+HLTMuonsSequence = cms.Sequence(
+    HLTL2MuonsFromL1TkSequence
+    + HLTPhase2L3OISequence
+    + HLTPhase2L3FromL1TkSequence
+    + HLTIter0Phase2L3FromL1TkSequence
+    + HLTIter2Phase2L3FromL1TkSequence
+    + HLTPhase2L3MuonsSequence
+)
+
+from ..modules.hltPhase2L3MuonFilter_cfi import *
+
+# The IO first HLT Muons sequence
+Phase2HLTMuonsSequenceIOFirst = cms.Sequence(
+    HLTL2MuonsFromL1TkSequence
+    + HLTPhase2L3FromL1TkSequence
+    + HLTIter0Phase2L3FromL1TkSequence
+    + HLTIter2Phase2L3FromL1TkSequence
+    + hltPhase2L3MuonFilter
+    + HLTPhase2L3OISequence
+    + HLTPhase2L3MuonsSequence
+)
+# The OI first HLT Muons sequence
+Phase2HLTMuonsSequenceOIFirst = cms.Sequence(
+    HLTL2MuonsFromL1TkSequence
+    + HLTPhase2L3OISequence
+    + hltPhase2L3MuonFilter
+    + HLTPhase2L3FromL1TkSequence
+    + HLTIter0Phase2L3FromL1TkSequence
+    + HLTIter2Phase2L3FromL1TkSequence
+    + HLTPhase2L3MuonsSequence
+)
+
+from Configuration.ProcessModifiers.phase2L2AndL3Muons_cff import phase2L2AndL3Muons
+
+phase2L2AndL3Muons.toReplaceWith(HLTMuonsSequence, Phase2HLTMuonsSequenceIOFirst)
+
+from Configuration.ProcessModifiers.phase2L3MuonsOIFirst_cff import phase2L3MuonsOIFirst
+
+(phase2L2AndL3Muons & phase2L3MuonsOIFirst).toReplaceWith(
+    HLTMuonsSequence, Phase2HLTMuonsSequenceOIFirst
+)

RecoMuon/L3TrackFinder/interface/phase2HLTMuonSelectorForL3.h

@@ -0,0 +1,81 @@
+#ifndef RecoMuon_L3TrackFinder_phase2HLTMuonSelectorForL3_H
+#define RecoMuon_L3TrackFinder_phase2HLTMuonSelectorForL3_H
+
+/**  \class phase2HLTMuonSelectorForL3
+ * 
+ *   Phase-2 L3 selector for Muons
+ *   This module allows to choose whether to perform 
+ *   Inside-Out or Outside-In reconstruction first for L3 Muons, 
+ *   performing the second pass only on candidates that were not
+ *   reconstructed or whose quality was not good enough. Required 
+ *   quality criteria are configurable, the default parameters 
+ *   match the requests of HLT Muon ID. 
+ *   When Inside-Out reconstruction is performed first, the resulting
+ *   L3 Tracks are filtered and geometrically matched with L2
+ *   Standalone Muons. If either the match is unsuccessful, or 
+ *   the L3 track is not of good-enough quality, the associated 
+ *   Standalone Muon will be re-used to seed the Outside-In step.
+ *   The Outside-In first approach follows a similar logic by 
+ *   matching the L3 tracks directly with L1 Tracker Muons. 
+ *   Then, when either the match fails or the track is not of 
+ *   good-enough quality, the L1 Tracker Muon is re-used to seed
+ *   the Inside-Out reconstruction.
+ *
+ *   \author Luca Ferragina (INFN BO), 2024
+ */
+
+#include "FWCore/Framework/interface/stream/EDProducer.h"
+#include "FWCore/Framework/interface/ESHandle.h"
+#include "FWCore/Framework/interface/Frameworkfwd.h"
+#include "FWCore/Framework/interface/ConsumesCollector.h"
+#include "FWCore/Framework/interface/EventSetup.h"
+#include "FWCore/Framework/interface/Event.h"
+#include "FWCore/Framework/interface/MakerMacros.h"
+#include "FWCore/ParameterSet/interface/ParameterSet.h"
+#include "FWCore/MessageLogger/interface/MessageLogger.h"
+#include "FWCore/ParameterSet/interface/ConfigurationDescriptions.h"
+#include "FWCore/Utilities/interface/ESGetToken.h"
+#include "FWCore/Utilities/interface/InputTag.h"
+
+#include "DataFormats/L1TMuonPhase2/interface/TrackerMuon.h"
+#include "DataFormats/MuonReco/interface/MuonFwd.h"
+#include "DataFormats/MuonSeed/interface/L2MuonTrajectorySeedCollection.h"
+#include "DataFormats/TrackReco/interface/Track.h"
+#include "DataFormats/TrackReco/interface/TrackFwd.h"
+
+namespace edm {
+  class ParameterSet;
+  class Event;
+  class EventSetup;
+}  // End namespace edm
+
+class phase2HLTMuonSelectorForL3 : public edm::stream::EDProducer<> {
+public:
+  // Constructor
+  phase2HLTMuonSelectorForL3(const edm::ParameterSet&);
+
+  // Destructor
+  ~phase2HLTMuonSelectorForL3() override = default;
+
+  // Default values
+  static void fillDescriptions(edm::ConfigurationDescriptions& descriptions);
+
+  // Select objects to be reused
+  void produce(edm::Event&, const edm::EventSetup&) override;
+
+private:
+  const edm::EDGetTokenT<l1t::TrackerMuonCollection> l1TkMuCollToken_;
+  const edm::EDGetTokenT<reco::TrackCollection> l2MuCollectionToken_;
+  const edm::EDGetTokenT<reco::TrackCollection> l3TrackCollectionToken_;
+
+  const bool IOFirst_;
+  const double matchingDr_;
+  const bool applyL3Filters_;
+  const double maxNormalizedChi2_, maxPtDifference_;
+  const int minNhits_, minNhitsMuons_, minNhitsPixel_, minNhitsTracker_;
+
+  // Check L3 inner track quality parameters
+  const bool rejectL3Track(l1t::TrackerMuonRef l1TkMuRef, reco::TrackRef l3TrackRef) const;
+};
+
+#endif