Shilei ZangUniversity of Colorado, Boulder

GMSB Meeting, 1 Aug 2008

QCD Control Sample

HLT; trkIso30; (dE>0)eHLT; trkIso90; Pt2>30; (dE>0) controlHLT; trkIso12; HoE90; Pt2>30; (dE>0); do not satisfy e controlHLT; trkIso12 ; HoE90; Pt2>30; (dE>0); do not satisfy e

*BkgGMSBBkg1/fbBlue: Red: control (or e) : 80 signal; 2698 bkgs control : 55 signal; 3157 bkgse : 61 from bkgs vs. -control vs. -control vs. e

Jet resolution:MET resolution: Signal yield:Control sample:

MET vs. for background (left) and for GMSB signal (right).k=5.0k=5.0pt1>80, pt2>20BkgGMSBMETMET has powerful separation. almost no correlation with Pt1, Pt2, trkIso. (but MET has.)

Signal yield:Control sample: HLT; HoE80; Pt2>20; Electron: haveSeeds && # of track (Pt>1.5; R=1Di-photons: Control sample:trkIso 12trkIso/Pt 0.1Pt1 >120 60 110&&Pt2>50 Pt1

*BkgGMSBBkgGMSBPt1Pt1Pt2Pt2trkIso1trkIso1trkIso2trkIso2

*BkgGMSBBkgGMSBMETMETMETMETtrkIso1trkIso1trkIso2trkIso2

*BkgGMSBBkgGMSBMETMETMETMETtrkIso1/Pt1trkIso1/Pt1trkIso2/Pt2trkIso2/Pt2

*BkgGMSBBkgGMSBMETMETMETMETPt1Pt1Pt2Pt2

*HoE80; Pt2>20;Blue: trkIso12 (550 evts)HoE80; Pt2>20;Blue: trkIso/Pt0.1 (771 evts)trkIsotrkIso/PtMETMET

*BkgGMSBBkgGMSBtrkIso1trkIso1trkIso2trkIso2MET/(Pt)MET/(Pt)MET/(Pt)MET/(Pt)

*BkgGMSBBkgGMSBtrkIso1/Pt1trkIso1/Pt1trkIso2/Pt2trkIso2/Pt2MET/(Pt)MET/(Pt)MET/(Pt)MET/(Pt)

*BkgGMSBBkgGMSBPt1Pt1Pt2Pt2MET/(Pt)MET/(Pt)MET/(Pt)MET/(Pt)

*BkgGMSBBkgGMSBPt1+Pt2Pt1+Pt2Pt2Pt2MET/(Pt)MET/(Pt)Pt1Pt1

*Blue: trkIso12 (550 evts)Blue: trkIso/Pt0.1 (771 evts)trkIsotrkIso/PtMET/(Pt)MET/(Pt)

*Pt2>30; w/o trkIsoBlue: Pt1>120 (2452 evts)Red: 8060 (3098 evts)Red: 20

*w/o trkIsoBlue: Pt1>110 && Pt2>50 (2249 evts)Red: Pt1

*BkgGMSBBkgGMSBPt1Pt1Pt2Pt2MET/(MET)MET/(MET)MET/(MET)MET/(MET)

*Blue: trkIso12 (550 evts)Blue: trkIso/Pt0.1 (771 evts)trkIsotrkIso/PtMET/(MET)MET/(MET)

*Pt2>30; w/o trkIsoBlue: Pt1>120 (2452 evts)Red: 8060 (3098 evts)Red: 20

*Di-photons; 1/fbMET/(MET)MET/(Pt)METSeparation: MET/(Pt) > MET > MET/(MET)

*MET/(Pt)Pt1 & Pt2MET/(Pt)The best choice now: MET/(Pt);Pt1, Pt2 together for the control sample(we can get enough control events!)Di-photons; 1/fb

*A new technique for mass variable (stopped for the moment)Momentum of two photons (known) Momentum of two gravitinos: P1x, P1y, P1z; P2x, P2y, P2z. (unknown)MET: METx, METy. (known)Generate P1x, P1y, P1z; P2x, P2y, P2z distributions according to GMSB MC truth. (take all GM1b-GM1g GMSB simulated events for this.) sample A.For each event i (not in sample A; already passed all cuts: iPt1>80, iPt2>20, iMET>80), use all events in sample A with |Pt1-iPt1|

*Require |mass(j)-mass(k)|

*METformula massPt1>90; Pt2>30Pt1>90; Pt2>30 BkgGMSB (GM1e)New Mass(preliminary)GMSBGMSB