Presentation is loading. Please wait.

Presentation is loading. Please wait.

PHANTOM Update Physics at TeV Colliders Workshop - Les Houches 2007 Ezio Maina U. of Torino.

Similar presentations


Presentation on theme: "PHANTOM Update Physics at TeV Colliders Workshop - Les Houches 2007 Ezio Maina U. of Torino."— Presentation transcript:

1 PHANTOM Update Physics at TeV Colliders Workshop - Les Houches 2007 Ezio Maina U. of Torino

2 Phantom Ballestrero, Belhouari,Bevilacqua,E.M. Dedicated event generator Complete 26 O(α 6 )+O(α 4 α s 2 ) pbar, e + e -- p-p, p-pbar, e + e -- Complete set of reactions up to pp 4l2j, ee 2l4j At LHC: q 1 q 2 f 1 f 2 f 3 f 4 f 5 f 6 O(α 6 )+O(α 4 α s 2 ) gg f 1 f 2 f 3 f 4 f 5 f 6, gqgq f 1 f 2 f 3 f 4, qqgg f 1 f 2 f 3 f 4 Exact matrix elements. No production decay or EVBA Fast One-shot: generates unweighted events for all processes simultaneously Efficient: good mapping of phase-space Multichannel + Vegas q 1 q 2 q 1 q 2 q 3 q 4 lv covered in Phase1.0 Accomando,Ballestrero,E.M. hep-ph/0504009

3 qqVV prod VV scattering Higgs top VV couplings

4 Exact vs VVqq-Prod Decay uuuuqqμν Single process qq=u-dbar,c-sbar mh=500GeV MADEVENT: qqWV Decay Tuned comparison Could produce exact result

5 VV scattering with PHANTOM Light Higgs VV weakly coupled Higgs Found check VV scattering Are SM predictions verified? Heavy (No) Higgs VV strongly coupled Higgs Not Found check VV scattering What restores Unitarity?

6 Models of EWSB Electroweak Chiral Lagrangian Butterworth,Cox,Forshaw PRD65(02)96014 Fabbrichesi,Vecchi hep-ph/0703236 many others Expand LL LL Amp in partial waves M= j a j (s) Pj (cos( ϑ )) SS =1 |a j (s)|1 Low Energy Th. M (VVVV) s/v 2 No H Unitarization: one example a j = a 0j /(1-ia 0j ) a 0j s Small s LET Large s a j 1 NOT UNIQUE!! Works well in ππ

7 Models of EWSB 2 Higgs low energy remnant of High Energy Strong Dynamics Severely constrained by EW Precision Tests Additional states may appear as resonances (Model dependent) Reduced HVV couplings Partial restoration of Unitarity up to the High Energy scale Model Independent Low Energy parametrization of composite Higgs models Giudice,Grojean,Pomarol,Rattazzi hep-ph/0703164 Barbieri,Bellazzini,Rychkov,Varagnolo arXiv:0706.0432 Additional dynamics,dimensions …….

8 Small sensitivity to MH in SM range SM predictions well defined. Not just counting exp Accomando,Ballestrero,Bolognesi,E.M.,Mariotti JHEP 0603(2006)093 hep-ph/0512219 qq4qlv ( EW) M(VW)>800GeV +p T +E+η+M ij cuts

9 qq4qμ + μ -- ( EW) M(VZ)>800GeV +p T +E+η+M ij cuts Accomando,Ballestrero,Belhouari,Maina PRD 75:113006,2007 hep-ph/0603167 100 fb -1 |η V |< 2

10 Looking for Mr. V Boson Butterworth, Ellis, Raklev hep-ph/0702150 70 250 GeV Alternatives? W jets Jet in W+jet

11 qq4qlv O(α 6 )+O(α 4 α s 2 ) Ballestrero, Bevilacqua,E.M. WVjj Wjjjj

12 Closer to the real world CMS Note 2007/005 Preliminary Torino+ Milano CMS Group+TH FAMOS Bkg:Alpgen+Madevent 430 fb -1 needed for S/B 1/2 =5 in 4qev

13 Conclusions Studying EWSB through VV scattering is hard Semileptonic channels essential New techniques for reconstructing hadronic Vs needed Plans Complete qq4qlv Alternative models of EWSB

14 Backup slides

15 Boson-Boson scattering and Unitarity

16 Selection 4qμν CMS Note

17 Selection 4qeν CMS Note

18 Selection 4qeν continued

19 Efficiency


Download ppt "PHANTOM Update Physics at TeV Colliders Workshop - Les Houches 2007 Ezio Maina U. of Torino."

Similar presentations


Ads by Google