“ “ Higgs” at high mass Higgs” at high mass As seen in previous days, issues are many and still under discussion this is my partial (imprecise?) summary ! Overview of experimental results (~1 fb-1 published, 5 fb-1 u review) theory: (Yellow Report 1, done!) Yellow Report 2 in preparation (differential distributions) What’s next? S.Bolognesi (Johns Hopkins University) Paris, 23 November 2011 Paris, 23 November 2011 Workshop on Implications of LHC results for TeV-scale Workshop on Implications of LHC results for TeV-scale physics (WG1) physics (WG1)
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“Higgs” at high mass As seen in previous days, issues are many and still under discussion this is my partial (imprecise?) summary ! Overview of experimental.
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““Higgs” at high massHiggs” at high mass
As seen in previous days, issues are many and still under discussion
this is my partial (imprecise?) summary !
Overview of
experimental results (~1 fb-1 published, 5 fb-1 under review)
theory: (Yellow Report 1, done!)
Yellow Report 2 in preparation (differential distributions)
What’s next?
S.Bolognesi (Johns Hopkins University)
Paris, 23 November 2011Paris, 23 November 2011
Workshop on Implications of LHC results for TeV-scale physics (WG1)Workshop on Implications of LHC results for TeV-scale physics (WG1)
Sources
First LHC to Terascale Workshop (Sept 2011):
LCH at LHC by J.R. Espinoza
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CMS AN-2010-35: Angular Analysis of Resonances pp → X → ZZ
by David Krohn (Harvard)JHU seminar: Path-Integral Jetswww.pha.jhu.edu/groups/particle-theory/seminars/talks/F11/talk.khron.pdf
Boson Boson scattering analysis by A.Ballestrero (INFN Torino)
LHC To Terascale Physics WS S.Bolognesi (Johns Hopkins University)2
Outline
Status: CMS and ATLAS results in a nutshell
→ what are the limiting factors?
Next: move to larger mass
improve sensitivity to lower xsec
→ which experimental and theoretical issues?
The final arbiter: VV scattering
LHC To Terascale Physics WS S.Bolognesi (Johns Hopkins University)3
Current status
“high” mass: > 200 GeV (i.e. H→WW, ZZ)
LHC To Terascale Physics WS S.Bolognesi (Johns Hopkins University)4
From HPC summary talk about HiggsFrom HPC summary talk about Higgs
Several channels
BR→sensitivity: almost reversed order !
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Limiting factors
WW→lnqq, ZZ→llqq limited by huge V+jets background, taken from simu/data with large theoretical/statistical error
ZZ→llnn:
WW→lnln at high mass limited by signal << WW background ( not effective)
• >400 GeV limited by Z+jets tail at high MET: not large but not well known (controlled with g+jets → statistical error+met uncertainty)
• 200-400 GeV limited by non-Z background (top, W+jets, WW)
ZZ→4l limited by statistics (only ZZ background: small and well known)
drives the UL for mH>350
drives the UL for mH 200-300
Future improvements ?
Combination of >5 different channels (ele, mu, btag, …) Robust!
Very optimized analyses, some space for further improvement. With higher lumi:
• use shape analyses (where not yet done)
• extract background (norm and shape) from data with lower uncertainty
• extract signal with multidimensional fit (now only mZZ fit)
LHC To Terascale Physics WS S.Bolognesi (Johns Hopkins University)8
What’s next ?
higher mass
lower xsec
LHC To Terascale Physics WS S.Bolognesi (Johns Hopkins University)9
1 TeV masses: not anymore “the” Higgs
→ General search for X→VV→4f:
→ importance of semileptonic final states
xsec larger than Higgs
at high mass still very low number of events per fb-1