{"action":"created","issue":{"url":"https://api.github.com/repos/cms-sw/cmssw/issues/9039","labels_url":"https://api.github.com/repos/cms-sw/cmssw/issues/9039/labels{/name}","comments_url":"https://api.github.com/repos/cms-sw/cmssw/issues/9039/comments","events_url":"https://api.github.com/repos/cms-sw/cmssw/issues/9039/events","html_url":"https://github.com/cms-sw/cmssw/pull/9039","id":75298589,"number":9039,"title":"Switch Voronoi subtraction from equalization based recovery of negative fluctuation to ghost-particle based clustering and energy resumming","user":{"login":"yslai","id":1032767,"avatar_url":"https://avatars.githubusercontent.com/u/1032767?v=3","gravatar_id":"","url":"https://api.github.com/users/yslai","html_url":"https://github.com/yslai","followers_url":"https://api.github.com/users/yslai/followers","following_url":"https://api.github.com/users/yslai/following{/other_user}","gists_url":"https://api.github.com/users/yslai/gists{/gist_id}","starred_url":"https://api.github.com/users/yslai/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/yslai/subscriptions","organizations_url":"https://api.github.com/users/yslai/orgs","repos_url":"https://api.github.com/users/yslai/repos","events_url":"https://api.github.com/users/yslai/events{/privacy}","received_events_url":"https://api.github.com/users/yslai/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/cms-sw/cmssw/labels/comparison-available","name":"comparison-available","color":"009800"},{"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/reconstruction-pending","name":"reconstruction-pending","color":"fbca04"},{"url":"https://api.github.com/repos/cms-sw/cmssw/labels/tests-approved","name":"tests-approved","color":"009800"}],"state":"open","locked":false,"assignee":null,"milestone":{"url":"https://api.github.com/repos/cms-sw/cmssw/milestones/51","html_url":"https://github.com/cms-sw/cmssw/milestones/Next%20CMSSW_7_5_X","labels_url":"https://api.github.com/repos/cms-sw/cmssw/milestones/51/labels","id":982516,"number":51,"title":"Next CMSSW_7_5_X","description":"","creator":{"login":"nclopezo","id":1944922,"avatar_url":"https://avatars.githubusercontent.com/u/1944922?v=3","gravatar_id":"","url":"https://api.github.com/users/nclopezo","html_url":"https://github.com/nclopezo","followers_url":"https://api.github.com/users/nclopezo/followers","following_url":"https://api.github.com/users/nclopezo/following{/other_user}","gists_url":"https://api.github.com/users/nclopezo/gists{/gist_id}","starred_url":"https://api.github.com/users/nclopezo/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/nclopezo/subscriptions","organizations_url":"https://api.github.com/users/nclopezo/orgs","repos_url":"https://api.github.com/users/nclopezo/repos","events_url":"https://api.github.com/users/nclopezo/events{/privacy}","received_events_url":"https://api.github.com/users/nclopezo/received_events","type":"User","site_admin":false},"open_issues":71,"closed_issues":558,"state":"open","created_at":"2015-02-17T08:21:25Z","updated_at":"2015-05-13T14:48:21Z","due_on":"2015-03-02T23:00:00Z","closed_at":null},"comments":7,"created_at":"2015-05-11T17:31:44Z","updated_at":"2015-05-13T15:52:27Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/cms-sw/cmssw/pulls/9039","html_url":"https://github.com/cms-sw/cmssw/pull/9039","diff_url":"https://github.com/cms-sw/cmssw/pull/9039.diff","patch_url":"https://github.com/cms-sw/cmssw/pull/9039.patch"},"body":"This patch addresses the Voronoi subtraction performance issues. Previously, the negative fluctuation are recovered by equalization. This pull request switches to a postive energy-only clustering, where the negative fluctuation are propagated through the clustering as ghost particles, and then resummed.\r\n\r\nThe expected performance difference is a deterioration of 0.5 GeV/c or 1% energy scale difference for 50 GeV jets in the 2.76 TeV PbPb system, due to the effect of ECAL zero suppression on the underlying event  - which is not handled in this implementation, as opposed to the previous equalization method."},"comment":{"url":"https://api.github.com/repos/cms-sw/cmssw/issues/comments/101722658","html_url":"https://github.com/cms-sw/cmssw/pull/9039#issuecomment-101722658","issue_url":"https://api.github.com/repos/cms-sw/cmssw/issues/9039","id":101722658,"user":{"login":"yslai","id":1032767,"avatar_url":"https://avatars.githubusercontent.com/u/1032767?v=3","gravatar_id":"","url":"https://api.github.com/users/yslai","html_url":"https://github.com/yslai","followers_url":"https://api.github.com/users/yslai/followers","following_url":"https://api.github.com/users/yslai/following{/other_user}","gists_url":"https://api.github.com/users/yslai/gists{/gist_id}","starred_url":"https://api.github.com/users/yslai/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/yslai/subscriptions","organizations_url":"https://api.github.com/users/yslai/orgs","repos_url":"https://api.github.com/users/yslai/repos","events_url":"https://api.github.com/users/yslai/events{/privacy}","received_events_url":"https://api.github.com/users/yslai/received_events","type":"User","site_admin":false},"created_at":"2015-05-13T15:52:27Z","updated_at":"2015-05-13T15:52:27Z","body":"@cvuosalo Updated. A performance deterioration of 0.5 GeV/c or 1% energy scale difference for 50 GeV jets in the 2.76 TeV PbPb system was found previously, and was the effect of ECAL zero suppression on the underlying event. This causes a small nonlinearity that was corrected by the previous equalization method, but not this simpler method."}}