# Presentation: 682579

## Higgs at the Tevatron and LHC

- Rick St. Denis – Glasgow University

## Outline

- Higgs Decay Modes at Tev and LHC
- The two paths
- The CDF sensitivity
- Scenario
- Conclusions
- Appendix:Vector Boson Fusion Production of Higgs at TeV and LHC

## ATLAS Channels

- Deliberately Ignore 

- Should we
- invest in this?

- W,Z we know!

## CDF Channels NOW Ntupled 1fb-1 

- Total

- WH(lbb)

- WH-WWW

- VBF

- gg-WW

- ZH(llbb)

- ZH(bb)

- Used WW
- correction
- For VBF

- Before
- Selection!

## CDF (2009?) For 8fb-1 

## The Two Paths

- H to WW depends on jets, leptons (VBF too). Same at LHC, CDF.  Have studied VBF and fascinating match of detectors to machines!
- ttH depends on jets, b-jets: tagging and rmass resolution. WH,ZH depends on same: Huge synergy. Very different path.
- There are two natural divisions of effort: those that need silicon and those that don’t. We have lepton expertise and should use it!

## CDF Limits: (WW:360 pb-1)

- X 12

- Jet Resolution

## VBF Production Features

- Missing Et
- High Pt Leptons
- 2 forward jets, opposite in rapidity, high mass
- Spin 0 Higgs correlates spins of leptons: e,parallel and neutrinos also
- e-jet about 1-1.5

- Same as WW, but with forward jets.  Do analyses together. Very unique events.

## Studies

- Backgrounds: top, fakes, WW
- WW *is* the right laboratory in any case, even if no Higgs.  Something has to keep the cross section under control
- Need to get detector understood using Z’s to get e,W’s for Missing Energy.
- Need to understand top, WW for backgrounds.
- Do the Higgs detection at the same time

## Rolandi: LP2005

**Objectives for the Pilot RUN**
**Reach a Luminosity of 10****32**
**Low Luminosity run at 25 ns separation**
**Difficult to speculate further  on what the performance****might be in the first year. As always, CERN accelerators departments will do their best ! **
**Lyn Evans**

## Tevatron Projections

- 2007

- 2009

## Scenario

- ATLAS 2007: Pilot Run, Z,W calib? 200pb-1
- ATLAS 2008: Physics, 1fb-1
- CDF 2007: 4fb-1 : HWW 4x3: at SM limit in the 140-170 range. TOP and W Mass improved as well, so SM fit limits narrower.
- Deviations building from expected limit: we focus on this range for ATLAS 2008. Perhaps SM fit narrowing on this range.
- Higgs is 130-150 OR 170-185. Perhaps SM Fit excludes upper range.
- CDF 2009: 3at 120: ATLAS 2011? For discovery. CDF Keeps running!?
- ATLAS 2010: 10fb-1 : Discover it for > 130.

## Summary/Conclusions

- CDF/ATLAS interest in W decay modes.
- Detector expertise/studies in Z,W to leptons: Where our efforts should be.
- Some jets interest, but not absolutely needed.
- WW is the right laboratory for studying EW Sym Breaking.
- Tevatron will have clear statements from Direct and Indirect searches when LHC searchs get serious.

## Appendix: VBF

## Study Characteristics at Tev and LHC for 160

## Pt, Rapidity of Leptons, Jets

- Quark
- Forward

- Pt Quark can
- be low

- Electron
- In CDF

- Reasonably
- Triggerable

- Tev, H=160

## Pt, Rapidity of Leptons, Jets

- Quark more
- Forward

- Pt Quark can
- be low

- Electron
- In CDF:
- wider distn
- At LHC

- Reasonably
- Triggerable

- LHC, H=160

## Rapidity of two quarks

- Min 
- of 2
- quarks

- Max 
- of 2
- quarks

- 
- of 2
- quarks

- Tev, H=160

## Rapidity of two quarks

- Min 
- –
- wider

- Max 
- of 2
- Quarks
- wider

- 
- of 2
- Quarks
- wider

- LHC, H=160

## Missing Energy

- Tev, H=160

- 60 GeV
- Met

- Met vs
- Pte

- Quark can
- be along
- Met

- Met 180o from e

## Missing Energy

- A bit larger at LHC

- LHC, H=160

## Lepton Correlations:e-e

- Tev, H=160

- e,eanticorrelated in 

-  (e,e)

## Lepton Correlations:e-e

- LHC, H=160

- e,e anticorrelated less sharply in 

-  (e,e)

## Lepton Correlations: e-

- Lepton Correlations: e-

- e,correlated
- in y,phi and
- have high pt

- Tev, H=160

- R

## Lepton Correlations

- e,better
- correlated

- LHC, H=160

## Masses

- High Invariant
-  Mass between
-      quarks

- Large Invariant
-  Mass between
-      leptons

- Mt for e 

- Tev, H=160

## Masses

- Higher Invariant
-  Mass between
-      quarks

- Larger Invariant
-  Mass between
-      leptons

- Mt for e 

- LHC, H=160

## Electron-Jet Separation

- Tev, H=160

## Electron-Jet Separation

- LHC, H=160

- Same l-j
- separation

## Backup

## HWW