Search for Stan Lai, Pekka K. Sinervo Exotics Meeting, April 20, - PowerPoint PPT Presentation

� ✁ � ✂ ✄ ✄ ✄ Search for Stan Lai, Pekka K. Sinervo Exotics Meeting, April 20, 2006 Result Blessing Outline: Review of Procedure Result Plots to be blessed 1

☛ ☞ ✍ ✎ ✏ ✍ ☛ ✍ ✌ ✌ ☞ ✍ ✑ ✒ ☞ ✓ ✔ ✘ ✎✗ ✌ ✑ ☛ ✂ � ✁ � ✂ ✄ ✁ ✄ ☎ ☛ ☛ ✙ ✡ ✁ ✡ ✡ ✁ ✡ ✏ ✏ Event Selection and Acceptance Look for decay ✆✠✟ ✆✞✝ Event Selection: 1 loose lepton ( GeV) 5 jets ( GeV, ) Source Uncertainty (%) ✓✖✕ GeV JES 4.2 boson, Cosmic/Conversion rejection PDF 1.0 loose SecVtx tags ISR/FSR 1.6 ✚✜✛ CDF II Preliminary CDF II Preliminary MC Model 0.5 4 3.5 Lep.ID 5 ) (%) 3 BTag 18 b 2.5 b → MC stats 1 2 H)/BR(H Total 19 1.5 1 t A(t 0.5 0 100 105 110 115 120 125 130 135 Higgs Mass [GeV] 2

Acceptance Plots for Blessing CDF II Preliminary CDF II Preliminary CDF II Preliminary CDF II Preliminary 4 Fraction of events per tag bin 3.5 0.3 ) (%) m m = 115 GeV/c = 115 GeV/c 2 2 H H 3 0.25 b 2.5 b 0.2 → 2 H)/BR(H 0.15 1.5 0.1 1 t A(t 0.05 0.5 0 0 100 105 110 115 120 125 130 135 0 1 2 3 4 5 N Higgs Mass [GeV] tag 3

☛ ☛ ✏ � ✝ ✄ ✆ ✂ ✚ ✛ ✡ ✆ ✆ ✆ ✡ ☎ ✄ ✏ ✡ ✄ ✁ ✄ ✁ ✄ ✄ ✁ ✁ ✡ ✄ ✁ ✄ ✄ ☛ ✗ ✂ ✄ ☛ ✗ ✏ ✂ ✁ ✗ � ✏ ✏ ✏ ☛ ✗ ✡ ✛ ✕ ✏ ✟ ✑ ✂ � ✏ ✏ ✗ ✏ ☛ ☛ ☛ ✌ ✞ ☞ ✘ ✗ ☛ ✛ ✆ ✁ Background Evaluation We evaluate three backgrounds: Mistag Background - events with -jets Use the Mistag Matrix to predict multi-mistags events Multijet Background - events without a boson in final state Using the vs Isolation method to find component in pretag sample Scale to the number of observed double tag + mistag events events Irreducible Background - events with a boson and -jets Find the MC fraction of these events compared to events with one fake -tag Multiply this fraction by the single fake tag background that was found in mistag background Sources considered are , AND , where there is a decay events 4

Mistag Evaluation Plots for Blessing -1 -1 -1 -1 CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb 200 500 predicted tags predicted tags 180 events / 0.4 units 160 400 events / 10 GeV observed tags 140 observed tags 120 300 100 200 80 60 100 40 20 0 0 0 20 40 60 80 100 120 140 160 180 200 -4 -3 -2 -1 0 1 2 3 4 E [GeV] pseudorapidity η T 5

� ✁ ✎ ✆ ✒ ✑ ✑ ✄ ✂ ✝ ☛ ✒ ✏ ✏ ✗ ✏ ✂ ☛ ✎ ✍ ✌ ✗ ✟ ✂ ✄ ✑ ✑ ✒ ☎ ✆ ✂ ✠ ☛ ✡ ☛ ☎ ✂ ✡ ✁ ✡ ☞ ✏ ✏ ☛ ✏ ✗ ✏ ✂ ✞ ✛ ✗ ✏ ✑ ✑ ✟ ✗ ✏ ✂ ✁ ✗ � ✏ ✞ � ✏ ✄ ✆ ✏ ✎ ✑ ✗ ✏ ✂ ✁ � ✗ ✂ ✏ � ✏ ✗ ✏ ✂ � ✏ ✗ ✁ Event Tally and Result Plot for blessing: -1 -1 CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb 4 4 10 10 Source Yield (events) 95% C.L. Limit Mistag Standard Model σ × BR(H → b b ) t t H ) [fb] ) [fb] 3 3 10 10 Irreducible b b QCD b b → → 2 2 10 10 BR(H BR(H Total Background Signal 10 10 × × ( GeV) σ σ Observed 1 1 1 100 100 105 105 110 110 115 115 120 120 125 125 130 130 135 135 Higgs Mass [GeV] Higgs Mass [GeV] Once backgrounds estimates finalized, the signal region was unblinded One event observed in the signal region 95% C.L. Limit ( GeV) on is 660 fb. ✆✞✝ For 95% C.L. limit we find . 6

✡ Event Display for Blessing Event with an identified, central muon, 5 jets, and three -tagged jets: CDF II Preliminary Run 167551, Event 3626393 2 1.5 Jet 1: 73.8 GeV 1 Y (cm) L = 7.6 mm xy Muon 26.9 GeV MET 48.1 GeV L = 3.4 mm 0.5 xy Jet 4: 23.6 GeV L = 3.5 mm xy 0 Jet 2: 41.4 GeV Jet 3: 27.9 GeV -0.5 Jet 5: 15 GeV -1.5 -1 -0.5 0 0.5 1 1.5 X (cm) 7

✡ Event Display for Blessing Event with an identified, central muon, 4 jets, and three -tagged jets: CDF II Preliminary Run 178151, Event 179433 Jet 1: 56 GeV 2 MET 60.9 GeV 1 L = 16 mm xy Jet 2: 54.8 GeV L = 2 mm Y (cm) Jet 3: 50.1 GeV xy 0 L = 1.1 mm xy -1 Jet 4: 37.1 GeV Muon 84.6 GeV -2 -2.5 -2 -1.5 -1 -0.5 0 0.5 1 1.5 2 X (cm) Note this event does not pass our selection criteria 8

Distribution Plots for Blessing -1 -1 CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb 0.6 0.6 -1 -1 CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb 0.5 0.5 observed event observed event events / 20 GeV events / 20 GeV 0.6 0.6 2 ttH (m =115/c ) H 0.4 0.4 irreducible 0.5 0.5 0.3 0.3 observed event observed event events / 40 GeV events / 40 GeV mistags and QCD 0.2 0.2 0.4 0.4 0.1 0.1 0.3 0.3 0 0 0 0 50 50 100 100 150 150 200 200 250 250 300 300 350 350 400 400 450 450 500 500 0.2 0.2 0.6 0.6 2 0.1 0.1 t t H (m = 115 GeV/c ) H observed event observed event 0.5 0.5 events / 20 GeV events / 20 GeV irreducible 0 0 0.4 0.4 0 0 100 100 200 200 300 300 400 400 500 500 600 600 700 700 800 800 900 900 1000 1000 H H [GeV] [GeV] mistags and QCD 0.3 0.3 T T -1 -1 CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb 0.2 0.2 0.6 0.6 2 ttH (m = 115 GeV/c ) 0.1 0.1 H 0.5 0.5 irreducible 0 0 0 0 50 50 100 100 150 150 200 200 250 250 300 300 350 350 400 400 450 450 500 500 events / 10 GeV/c events / 10 GeV/c observed event observed event mistags and QCD 0.4 0.4 0.6 0.6 0.3 0.3 observed event observed event 0.5 0.5 events / 20 GeV events / 20 GeV 0.4 0.4 0.2 0.2 0.3 0.3 0.1 0.1 0.2 0.2 0 0 0.1 0.1 0 0 20 20 40 40 60 60 80 80 100 120 140 160 180 200 220 240 100 120 140 160 180 200 220 240 Lepton Pt [GeV/c] Lepton Pt [GeV/c] 0 0 0 0 50 50 100 100 150 150 200 200 250 250 300 300 350 350 400 400 450 450 500 500 bb Mass [GeV] bb Mass [GeV] 9

Distribution Plots for Blessing -1 -1 CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb 0.6 0.6 observed event observed event 0.5 0.5 events / 20 GeV events / 20 GeV 0.4 0.4 0.3 0.3 0.2 0.2 0.1 0.1 0 0 -1 -1 0 0 50 50 100 100 150 150 200 200 250 250 300 300 CDF II Preliminary L = 320 pb CDF II Preliminary L = 320 pb 0.6 0.6 2 t t H (m = 115 GeV/c ) H observed event observed event 0.6 0.6 0.5 0.5 2 t t H (m = 115 GeV/c ) H observed event observed event irreducible 0.5 0.5 events / 20 GeV events / 20 GeV events / 20 GeV events / 20 GeV irreducible 0.4 0.4 0.4 0.4 mistags and QCD mistags and QCD 0.3 0.3 0.3 0.3 0.2 0.2 0.2 0.2 0.1 0.1 0.1 0.1 0 0 0 0 50 50 100 100 150 150 200 200 250 250 300 300 0 0 0 0 50 50 100 100 150 150 200 200 250 250 300 300 0.6 0.6 Missing Transverse Energy [GeV] Missing Transverse Energy [GeV] observed event observed event 0.5 0.5 events / 20 GeV events / 20 GeV 0.4 0.4 0.3 0.3 0.2 0.2 0.1 0.1 0 0 0 0 50 50 100 100 150 150 200 200 250 250 300 300 Jet Et [GeV] Jet Et [GeV] 10

✠ � ✝✡ ✆ � ✞✟ ✝ ✆ ☞ � ☎ � ✁ ✍ ✏ � ✑ ☎ ✁ ✔ ✝ ☛ Summary Performed blind search for ✁✄✂ production First Limits set on ✁✄✂ production Expect background of events, observe 1 event Another event has 3 -tags, but misses the jet cut Limit set at 660 fb, 168 times above SM expectation for ✌✎✍ ✑✓✒ 11