First version of PowhegResHook

[cmsbuild]

This Pythia8 hook is a C++ port of the alternative hook-based algorithm by Jezo et. al. (arXiv:1607.04538, Appendix B.2) for showering Powheg ttb_NLO_dec and b_bbar_4l processes.

Caveats:

• While the authors found quite good agreement with the reference algorithm, some modifications will be necessary in the future to get complete agreement
• The hook might not be compatible yet with the emission veto hook that we normally use for Powheg+Pythia8.
  Automatically ported from CMSSW_8_1_X First version of PowhegResHook #16546 (original by @intrepid42).

[cmsbuild]

A new Pull Request was created by @cmsbuild for CMSSW_9_0_X.

It involves the following packages:

GeneratorInterface/Pythia8Interface

@cmsbuild, @govoni, @perrozzi, @thuer, @davidlange6 can you please review it and eventually sign? Thanks.
@agrohsje, @mkirsano this is something you requested to watch as well.
@slava77, @smuzaffar you are the release manager for this.

cms-bot commands are listed here #13028

[perrozzi]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/16369/console

[cmsbuild]

Pull request #16604 was updated. @cmsbuild, @govoni, @perrozzi, @thuer, @davidlange6 can you please check and sign again.

[davidlange6]

please test

[cmsbuild]

The tests are being triggered in jenkins.
https://cmssdt.cern.ch/jenkins/job/ib-any-integration/16708/console

[cmsbuild]

+1
Tested at: 6e87d99
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-16604/16708/summary.html

[cmsbuild]

Comparison job queued.

[cmsbuild]

Comparison is ready
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-16604/16708/summary.html

The workflows 1003.0, 1001.0, 1000.0, 140.53, 136.731, 4.22 have different files in step1_dasquery.log than the ones found in the baseline. You may want to check and retrigger the tests if necessary. You can check it in the "files" directory in the results of the comparisons