{"action":"created","issue":{"url":"https://api.github.com/repos/cms-sw/cmssw/issues/12901","labels_url":"https://api.github.com/repos/cms-sw/cmssw/issues/12901/labels{/name}","comments_url":"https://api.github.com/repos/cms-sw/cmssw/issues/12901/comments","events_url":"https://api.github.com/repos/cms-sw/cmssw/issues/12901/events","html_url":"https://github.com/cms-sw/cmssw/pull/12901","id":125858483,"number":12901,"title":"Add Pythia8 UserHook for Resonance decay filtering","user":{"login":"bendavid","id":4920798,"avatar_url":"https://avatars.githubusercontent.com/u/4920798?v=3","gravatar_id":"","url":"https://api.github.com/users/bendavid","html_url":"https://github.com/bendavid","followers_url":"https://api.github.com/users/bendavid/followers","following_url":"https://api.github.com/users/bendavid/following{/other_user}","gists_url":"https://api.github.com/users/bendavid/gists{/gist_id}","starred_url":"https://api.github.com/users/bendavid/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/bendavid/subscriptions","organizations_url":"https://api.github.com/users/bendavid/orgs","repos_url":"https://api.github.com/users/bendavid/repos","events_url":"https://api.github.com/users/bendavid/events{/privacy}","received_events_url":"https://api.github.com/users/bendavid/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/cms-sw/cmssw/labels/comparison-pending","name":"comparison-pending","color":"fbca04"},{"url":"https://api.github.com/repos/cms-sw/cmssw/labels/generators-pending","name":"generators-pending","color":"fbca04"},{"url":"https://api.github.com/repos/cms-sw/cmssw/labels/orp-pending","name":"orp-pending","color":"fbca04"},{"url":"https://api.github.com/repos/cms-sw/cmssw/labels/pending-signatures","name":"pending-signatures","color":"eb6420"},{"url":"https://api.github.com/repos/cms-sw/cmssw/labels/tests-pending","name":"tests-pending","color":"fbca04"}],"state":"open","locked":false,"assignee":null,"milestone":{"url":"https://api.github.com/repos/cms-sw/cmssw/milestones/57","html_url":"https://github.com/cms-sw/cmssw/milestones/Next%20CMSSW_8_0_X","labels_url":"https://api.github.com/repos/cms-sw/cmssw/milestones/57/labels","id":1362157,"number":57,"title":"Next CMSSW_8_0_X","description":"","creator":{"login":"smuzaffar","id":4115138,"avatar_url":"https://avatars.githubusercontent.com/u/4115138?v=3","gravatar_id":"","url":"https://api.github.com/users/smuzaffar","html_url":"https://github.com/smuzaffar","followers_url":"https://api.github.com/users/smuzaffar/followers","following_url":"https://api.github.com/users/smuzaffar/following{/other_user}","gists_url":"https://api.github.com/users/smuzaffar/gists{/gist_id}","starred_url":"https://api.github.com/users/smuzaffar/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/smuzaffar/subscriptions","organizations_url":"https://api.github.com/users/smuzaffar/orgs","repos_url":"https://api.github.com/users/smuzaffar/repos","events_url":"https://api.github.com/users/smuzaffar/events{/privacy}","received_events_url":"https://api.github.com/users/smuzaffar/received_events","type":"User","site_admin":false},"open_issues":45,"closed_issues":530,"state":"open","created_at":"2015-10-18T08:35:44Z","updated_at":"2016-01-21T15:53:33Z","due_on":null,"closed_at":null},"comments":7,"created_at":"2016-01-11T01:19:10Z","updated_at":"2016-01-21T16:02:25Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/cms-sw/cmssw/pulls/12901","html_url":"https://github.com/cms-sw/cmssw/pull/12901","diff_url":"https://github.com/cms-sw/cmssw/pull/12901.diff","patch_url":"https://github.com/cms-sw/cmssw/pull/12901.patch"},"body":"Allows to retry resonance decays until desired configuration is present.  This is much faster than filtering at the event level, since only the resonance decays are retried.  It also works for LHE input without throwing away any events, with the caveat that only the decays handled by pythia are retried (but decay products from the lhe level can still be included in the counting, eg for counting the combined number of leptons at LHE + pythia decay level for Higgs associated production, etc)\r\n\r\nIn order for this new userhook to work with jet matching, emission veto, etc, a further UserHook was required to act as a generic mechanism to run multiple user hooks simultaneously (and this is now used by default)\r\n\r\nAn example gen fragment is provided in \r\nGeneratorInterface/Pythia8Interface/test/resonanceDecayFilter.py\r\n\r\nImmediate use case is some SUSY signal generation which requires some filtering of Higgs decays (two Higgs in each event and requesting at least one H->gamma gamma decay)\r\n\r\n"},"comment":{"url":"https://api.github.com/repos/cms-sw/cmssw/issues/comments/173617322","html_url":"https://github.com/cms-sw/cmssw/pull/12901#issuecomment-173617322","issue_url":"https://api.github.com/repos/cms-sw/cmssw/issues/12901","id":173617322,"user":{"login":"bendavid","id":4920798,"avatar_url":"https://avatars.githubusercontent.com/u/4920798?v=3","gravatar_id":"","url":"https://api.github.com/users/bendavid","html_url":"https://github.com/bendavid","followers_url":"https://api.github.com/users/bendavid/followers","following_url":"https://api.github.com/users/bendavid/following{/other_user}","gists_url":"https://api.github.com/users/bendavid/gists{/gist_id}","starred_url":"https://api.github.com/users/bendavid/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/bendavid/subscriptions","organizations_url":"https://api.github.com/users/bendavid/orgs","repos_url":"https://api.github.com/users/bendavid/repos","events_url":"https://api.github.com/users/bendavid/events{/privacy}","received_events_url":"https://api.github.com/users/bendavid/received_events","type":"User","site_admin":false},"created_at":"2016-01-21T16:02:25Z","updated_at":"2016-01-21T16:02:25Z","body":"I checked with the JetMatchingMadgraph hook that the jet matching results don't change adding this code and combining with the resonance decay filter.  Of course that doesn't test the full range of possible UserHook functionality."}}