Fix beamspot in PATElectronProducer

[RSalvatico]

PR description:

There are two related bugs in the PATElectronProducer:

1. The variable beamSpot
   

   cmssw/PhysicsTools/PatAlgos/plugins/PATElectronProducer.cc

   Line 523 in 4a85623

   reco::BeamSpot beamSpot;

   
   is initialized but never set to the actual collection of BeamSpot. Nevertheless, it is used throughout the code. As a result, the BS2D and BS3D variables (impact parameters wrt the beamspot)
   

   cmssw/PhysicsTools/PatAlgos/plugins/PATElectronProducer.cc

   Line 1427 in 4a85623

   anElectron.setDB(track->dxy(beamspot), track->dxyError(beamspot), pat::Electron::BS2D);

   
   are essentially trash. For example, before the fix gsfTrack->dxy(beamspot) tends to be a very large number wrt the equivalent for muons.

2. There is no check on the validity of the beamspot, so
   

   cmssw/PhysicsTools/PatAlgos/plugins/PATElectronProducer.cc

   Line 524 in 4a85623

   bool beamSpotIsValid = false;

   
   is never set to true. As a result, the BS3D error
   

   cmssw/PhysicsTools/PatAlgos/plugins/PATElectronProducer.cc

   Line 1435 in 4a85623

   d0_err = beamspotIsValid ? result.second.error() : -1.0;

   
   is always -1.0.

This PR fixes 1. and 2.

PR validation:

I ran several workflows and saw reasonable values for the impact parameters wrt the beamspot.

If this PR is a backport please specify the original PR and why you need to backport that PR. If this PR will be backported please specify to which release cycle the backport is meant for:

It does not need a backport if future re-minis are going to happen with CMSSW >= 142X (probably the case?).

FYI @afiqaize @cochando @SanghyunKo

[cmsbuild]

cms-bot internal usage

[cmsbuild]

+code-checks

Logs: https://cmssdt.cern.ch/SDT/code-checks/cms-sw-PR-46412/42266

[cmsbuild]

A new Pull Request was created by @RSalvatico for master.

It involves the following packages:

• PhysicsTools/PatAlgos (xpog, reconstruction)

@cmsbuild, @ftorrresd, @hqucms, @jfernan2, @mandrenguyen can you please review it and eventually sign? Thanks.
@AlexDeMoor, @Ming-Yan, @Senphy, @ahinzmann, @andrzejnovak, @azotz, @castaned, @gkasieczka, @gouskos, @gpetruc, @hatakeyamak, @jdamgov, @jdolen, @mariadalfonso, @mbluj, @mmarionncern, @nhanvtran, @rappoccio, @schoef, @seemasharmafnal this is something you requested to watch as well.
@antoniovilela, @mandrenguyen, @rappoccio, @sextonkennedy you are the release manager for this.

cms-bot commands are listed here

[RSalvatico]

type egamma, bug-fix

[RSalvatico]

@cmsbuild, please test

[cmsbuild]

+1

Size: This PR adds an extra 32KB to repository
Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-cca9d2/42245/summary.html
COMMIT: 50e2d9f
CMSSW: CMSSW_14_2_X_2024-10-15-2300/el8_amd64_gcc12
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-sw/cmssw/46412/42245/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• You potentially removed 3 lines from the logs
• Reco comparison results: 35 differences found in the comparisons
• DQMHistoTests: Total files compared: 44
• DQMHistoTests: Total histograms compared: 3335129
• DQMHistoTests: Total failures: 419
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3334690
• DQMHistoTests: Total skipped: 20
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 43 files compared)
• Checked 193 log files, 163 edm output root files, 44 DQM output files
• TriggerResults: no differences found

[jfernan2]

+1

[hqucms]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next master IBs (tests are also fine). This pull request will now be reviewed by the release team before it's merged. @sextonkennedy, @mandrenguyen, @antoniovilela, @rappoccio (and backports should be raised in the release meeting by the corresponding L2)

[mandrenguyen]

+1