Added new beamspot with fixed emittance for 2017 pp @ 5 TeV

[gsfs]

PR description:

This PR adds a new beamspot option for MC. This beamspot is a modification of that previously used for MC for 2017 pp data @ 5 TeV. It was known for some time that the original beam smearing did not match that in data but it was felt that the difference was small enough not to matter. However, now that we have the much larger 2018 PbPb dataset, new analyses may be possible that are sensitive to the difference in beam smearing in pp. Therefore, it was decided to add a more accurate beam smearing option in CMSSW. This is being put in CMSSW_9_4_X since this is the only CMSSW version used for analyzing that 2017 pp data.

PR validation:

This exact code has already been used successfully to generate numerous private MC samples with the new beamspot option. We now want the ability to generate official samples and so need this code in an official CMSSW release.

Back port information

This is a backport of PR #28580 which is now merged into master.

[cmsbuild]

A new Pull Request was created by @gsfs for CMSSW_9_4_X.

It involves the following packages:

Configuration/StandardSequences
IOMC/EventVertexGenerators

@civanch, @kpedro88, @cmsbuild, @franzoni, @mdhildreth, @fabiocos, @davidlange6 can you please review it and eventually sign? Thanks.
@makortel, @felicepantaleo, @GiacomoSguazzoni, @rovere, @VinInn, @Martin-Grunewald, @dgulhan this is something you requested to watch as well.
@davidlange6, @slava77, @fabiocos you are the release manager for this.

cms-bot commands are listed here

[civanch]

@gsfs , we use first making PR for the master and after integration backport to previous releases. So, please, make the same PR for 11_1_0

[gsfs]

OK, I wasn't sure that was necessary in this particular case since this beamspot cannot be useful in any releases other than 9_4_X. I will work on that.

[gsfs]

New PR #28580 created merging these code changes into Master.

[civanch]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-run-pr-tests/3866/console Started: 2019/12/09 09:50

[cmsbuild]

+1
Tested at: c47754a
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-37c3d0/3866/summary.html

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-37c3d0/3866/summary.html

Comparison Summary:

• No significant changes to the logs found
• Reco comparison results: 0 differences found in the comparisons
• DQMHistoTests: Total files compared: 27
• DQMHistoTests: Total histograms compared: 2721493
• DQMHistoTests: Total failures: 106
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 2721225
• DQMHistoTests: Total skipped: 162
• DQMHistoTests: Total Missing objects: 0

[civanch]

+1

[fabiocos]

+operations

correct backport

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_9_4_X IBs (tests are also fine) and once validation in the development release cycle CMSSW_11_1_X is complete. This pull request will now be reviewed by the release team before it's merged. @davidlange6, @slava77, @smuzaffar, @fabiocos (and backports should be raised in the release meeting by the corresponding L2)

[gsfs]

Identical PR for master was PR #28580 which is now merged. For completeness, I added this information to the description of this PR at the top of this page.

[fabiocos]

+1