pick ecal fraction of 0 for a candidate with trackMomentum 0

[slava77]

This is a follow up to investigation of origins of the NaN PFCandidate that leads to a crash in
https://hypernews.cern.ch/HyperNews/CMS/get/recoDevelopment/1385.html

Here, the ecal raw energy was set to infinity, while the momentum is still OK.
Then later in the PFCandConnector, in the process of updating the momentum to account for nuclear interations, the candidate momentum is updated based on the calorimeter energy values. That's the point where the final candidate momentum turns to a NaN.

@bachtis please check if fraction=0 makes sense in this case.
If confirmed, I'd run more tests and propagate to 75X/76X.

[cmsbuild]

A new Pull Request was created by @slava77 (Slava Krutelyov) for CMSSW_7_4_X.

pick ecal fraction of 0 for a candidate with trackMomentum 0

It involves the following packages:

RecoParticleFlow/PFProducer

@cmsbuild, @cvuosalo, @slava77 can you please review it and eventually sign? Thanks.
@mmarionncern, @bachtis, @lgray this is something you requested to watch as well.
You can sign-off by replying to this message having '+1' in the first line of your reply.
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@Degano you are the release manager for this.
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[slava77]

@cmsbuild please test

[cmsbuild]

The tests are being triggered in jenkins.

[cmsbuild]

+1
Tested at: 66af8e0
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-11302/8184/summary.html

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-11302/8184/summary.html

[slava77]

@cmsbuild please test
to refresh the tests before signing it

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/8789/console

[cmsbuild]

+1
Tested at: 66af8e0
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-11302/8789/summary.html

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-11302/8789/summary.html

[slava77]

+1

for #11302 66af8e0

• in rare cases pf candidate ecal energy could be set to infinity, which eventually leads to NaN momentum; set ecal energy to 0 instead (OK'd by @bachtis in private communication).
• jenkins tests pass and comparisons with baseline show no differences

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_7_4_X IBs (tests are also fine) and once validation in the development release cycle CMSSW_7_6_X is complete. This pull request requires discussion in the ORP meeting before it's merged. @davidlange6, @Degano, @smuzaffar

[davidlange6]

+1