Search for Higgs in H WW lνlν

Transcription

1 Search for Higgs in H WW lνlν John Alison University of Pennsylvania on behalf of the ATLAS Collaboration

2 Higgs Physics Standard Model Remarkably Accurate Description Data. One Remaining Piece: Higgs Boson. Data predict m(h) below ~ GeV Best Fit for Higgs Mass "! LEP 95% CL Tevatron 95% CL arxiv:9.975 Theory uncertainty Fit including theory errors Fit excluding theory errors M H 3# # # sin Theory vs Experiment (5) M Z " Z! had Rlep,l A FB A l (LEP) A l (SLD) lept % eff (Q ) FB,c A FB,b A FB A c A b Rc Rb $ # had (M ) Z M W " W m c m b m t arxiv: (O fit - O meas ) /! meas A l (L A l (S lept sin % eff ( (5) $ # had

3 Searching for the Higgs Branching ratios - -3 arxiv:.593 cc bb gg Z WW ZZ M H LHC HIGGS XS WG [GeV/c ] H WW lνlν Strongest sensitivity over broad range of m(h) Critical in the region between LEP and SM EWK exclusion Reconstructable Cross-section [pb] - -3 gg H WW ll qq qqh qq ( l E T ) h gg H gg H ZZ llll m H

4 9 Entries Dilepton Selection 5 Data stat) 8 ATLAS Preliminary SM (sys WW WZ/ZZ/W 7 s = 7 TeV, L dt =.7 fb t t Single Top 6 H WW e e Z+jets W+jets H [5 GeV] M 3 ee Data / MC 3 Hww Analysis 5.5 M ee Entries / GeV Entries / GeV Missing Energy Jet Veto Exploit Higgs properties Spin-. Expected Mass Range Data / MC ta / MC 45 ATLAS Preliminary Data SM (sys stat) 4 No WW WZ/ZZ/W s = 7 TeV, clear mass peak L dt =.7 fb t t Single Top Z+jets W+jets (data driven) Data SM (sys stat) H WW l l + jets ATLAS Preliminary L dt =.7 fb s = 7 TeV, H WW l l + jets H [5 GeV] Challenging Analysis Many backgrounds After Hww Selection All channels WW H [5 GeV] WZ/ZZ/W t t Single Top Z+jets W+jets (data driven) M T H [5 GeV] M T

5 Results 95% CL Limit on / SM ATLAS Preliminary Observed Expected!! CLs Limits H WW Ldt =.7 fb s (*) l l = 7 TeV m H

6 Results "! LEP 95% CL Tevatron 95% CL arxiv:9.975 ATLAS Hww Expected Excluded 3# 4 # 3 Theory uncertainty Fit including theory errors Fit excluding theory errors # M H

7 The Future is Now. In the works 95% CL Limit on!/! SM 95% CL Limit on!/! SM Projections, s=7 TeV fb fb 5fb TeVatron LEP Presented Here ATLAS Preliminary (Simulation) m H Figure 3: Combined sensitivity for different integrate median sensitivities and right gives the 3σ sensitivity. P are shown for comparison. Its a great time to be doing Higgs Physics!

8 Bonus

9 Combined Limit 95% CL Limit on / SM ATLAS Preliminary Observed Expected!! CLs Limits Ldt =.-.3 fb s = 7 TeV m H

10 The future is now. Integrated Luminosity, fb ATLAS Preliminary (Simulation) 5! s=7 TeV 5! s=8 TeV 3! s=7 TeV 3! s=8 TeV 95% CL s=7 TeV 95% CL s=8 TeV m H

11 The Future is Now. Sensitivity to!/! SM 3! obs., fb 3! obs., fb 3! obs., 5 fb TeVatron 95% CL exc. LEP 95% CL exc. ATLAS Preliminary (Simulation) Median sensitivity s=7 TeV Projections m H

12 Full Mass Range 95% CL Limit on / SM ATLAS Preliminary Observed Expected!! CLs Limits Ldt =.-.3 fb s = 7 TeV m H

13 Hww Sensitivity H!WW!l"l"