Gluon Gluon to jpsi jpsi CMS Meeting 8-20 CMS B-Physics meeting

Typical Feynman diagrams of pair production in p p collision at leading order in color-singlet scheme CMS Meeting 8-20 CMS B-Physics meeting

Typical Feynman diagrams of pair production in p p collision at leading order in color-singlet scheme The generator is on the basis of FDC system(arXiv: hep-ph/0407058), and the generator could generate events in color-singlet and –octet scheme, respectively. CMS Meeting 8-20 CMS B-Physics meeting

Comparison between theoretical cross-section calculations and the results of my generator (see arxiv-0903.0954v3 for mathematica results) Down limit (2jpsi) ( ) Theoretical calculations in Mathematica Generator results Single-color Octet-color 5GeV 1.08pb 1.15pb 1.329pb 1.492pb 6GeV 0.37pb 0.74pb 0.402pb 0.908pb 7GeV 0.14pb 0.49pb 0.144pb 0.583pb CMS Meeting 8-20 CMS B-Physics meeting

Signals If set the down limit of Pt of double jpsi at 5GeV，because if Pt of jpsi was lower than 5GeV, the c quark fragmentation is not appropriate. cross-section of single-color model is 1.125pb; cross-section of octet-color model is 1.131pb. (10 TeV) This result has included branching ratio of jpsi to mumu:5.6% for each jpsi CMS Meeting 8-20 CMS B-Physics meeting

CMSSW_3_1_1, 10 TeV Model Pre-selection Color-singlet (100,000 events) 93030 Color-octet (100,000 events) 88249 Pre-selection: dimuon with different charge, Pt >0.7, |eta|<2.5, invariant mass (3.0, 3.2) CMS Meeting 8-20 CMS B-Physics meeting

Recomuon Number (trackermuon) Octet Singlet Singlet CMS Meeting 8-20 CMS B-Physics meeting

Inva_mass fitting 2 Cut the first di-muon mass: 2.9-3.3; Two vertex fitting, chi-square<100. Fitting area 3.0-3.2 6566 CMS Meeting 8-20

(pt<3&&fabs(eta)<1)||(pt<3-(1. 5/0. 2 (pt<3&&fabs(eta)<1)||(pt<3-(1.5/0.2*(fabs(eta)-1))&&fabs(eta)<1.2&&fabs(eta)>1) ||(pt<1.5-(0.8/1.3*(fabs(eta)-1.2))&&fabs(eta)<2.5&&fabs(eta)>1.2)) CMS Meeting 8-20

Muon +track Cut the first di-muon mass: 2.9-3.3; Two vertex fitting, chi-square<100. Fitting area 3.0-3.2 11088.7 CMS Meeting 8-20

Octet 2D_pt Bin:0-4,4-7,7-10,10-15,15-25 CMS Meeting 8-20 CMS B-Physics meeting

General Efficiency Trig is efficiency of trigger path to select events. Final-parti-reco is efficiency of final particles like muon, photon, jet, etc. CMS Meeting 8-20