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V.A. K hoze (IPPP, Durham & PINP)

Studying the BSM Higgs sector by forward proton tagging at the LHC. 20 th Sept.2008. V.A. K hoze (IPPP, Durham & PINP). (Based on works with S. H einemeyer, A. M artin, M. R yskin, W.J. S tirling, M. T asevsky and G. W eiglein).

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V.A. K hoze (IPPP, Durham & PINP)

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  1. Studying the BSM Higgs sector by forward proton tagging at the LHC 20th Sept.2008 V.A. Khoze(IPPP, Durham & PINP) (Based on works with S.Heinemeyer, A.Martin, M.Ryskin, W.J.Stirling, M.Tasevsky and G.Weiglein) main aim:to demonstrate that theCentral Exclusive Diffractive Production can provide unique advantages for probing the BSM Higgs sector

  2. two-faceted IPPP MHV N=2 SQCD U(1)s

  3. PLAN • Introduction(gluonic Aladdin’s lamp) • 2. Central Exclusive Diffractive Production (only a taste). • 3. Prospects for CED MSSM Higgs-boson production. • 4. Other BSM scenarios. • 5. Conclusion.

  4. The LHC is a discovery machine ! • CMS & ATLASwere designed and optimised to look beyond the SM • High -pt signatures in the central region • But… • Main physics ‘goes Forward’ • Difficult background conditions, pattern recognition, Pile Up... • The precision measurements are limited by systematics • (luminositygoal ofδL ≤5% , machine ~10%) • Lack of : • Threshold scanning , resolution of nearly degenerate states • (e.g. MSSM Higgs sector) • Quantum number analysing • Handle on CP-violating effects in the Higgs sector • Photon – photon reactions , … The LHC is a very challenging machine! The LHC is not a precision machine (yet) ! ILC/CLIC chartered territory p p RG Is there a way out? X YES  Forward Proton Tagging Rapidity Gaps  Hadron Free Zones matchingΔ Mx ~δM (Missing Mass) RG p p

  5. Forward Proton Taggersas a gluonicAladdin’s Lamp • (Old and NewPhysics menu) • Higgs Hunting(the LHC ‘core business’) • Photon-Photon, Photon - HadronPhysics. • ‘Threshold Scan’:‘Light’ SUSY … • Various aspects of DiffractivePhysics (soft & hard ). • •High intensityGluon Factory(underrated gluons) (~20 mln quraks vs 417 ‘tagged’ g at LEP) • QCD test reactions, dijet P-luminosity monitor • Luminometry • Searches for new heavy gluophilic states • and many other goodies… • FPT • Would provide a unique additional tool to complement the conventionalstrategies at theLHCandILC. Higgs is only a part of the broad EW, BSM and diffractiveprogram@LHC wealth of QCD studies, glue-glue collider, photon-hadron, photon-photon interactions… FPT  will open upan additional richphysics menu ILC@LHC

  6. (Khoze-Martin-Ryskin1997-2008) -4 (CDPE) ~ 10  (incl) (A. Kaidalov) New CDF results not so long ago: between Scylla and Charibdis: orders of magnitude differences in the theoretical predictions are now a history

  7. (Mike Albrow) Visualization of QCD Sudakov formfactor arXiv:0712.0604 , PRD-2008 A killing blow to the wide range of theoretical models. CDF d

  8. Current consensus on the LHC Higgs search prospects • SM Higgs : detection is in principle guaranteed for any mass. • In the MSSMh-boson most probably cannot escape detection, and in large areas of parameter space other Higgses can be found. • But there are still troublesomeareas of the parameter space: • intense coupling regime of MSSM, MSSM with CP-violation… • More surprises may arise in other SUSY • non-minimal extensions: NMSSM…… • ‘Just’ a discovery will not be sufficient! • After discovery stage(HiggsIdentification): • The ambitious program of precise measurements of the Higgs mass, width, couplings, • and, especially of the quantum numbers and CP properties would require • an interplay with a ILC . with a bit of personal flavour (A.Heijboer, A.Meyer, I. Thukerman) mH (SM) <160 GeV @95% CL

  9. The main advantages of CED Higgs production • Prospects for high accuracy (~1%) mass measurements • (irrespectively of the decay mode). • Quantum number filter/analyser. • ( 0++dominance ;C,P-even) • H ->bb opens up (Hbb- coupl.) • (gg)CED bb inLO ; NLO,NNLO, b- masseffects - controllable. • For some areas of the MSSM param. spaceCEDP may become adiscovery channel! • H→WW*/WW - an added value (less challenging experimentally + small bgds., better PUcond. ) • New leverage –proton momentum correlations (probes of QCD dynamics , CP- violation effects…) H How do we know what we’ve found?  LHC : ‘after discovery stage’,Higgs ID…… mass, spin, couplings to fermions and Gauge Bosons, invisible modes…  for all these purposes the CEDP will be particularly handy !

  10. SM Higgs WW decay channel: require at least one W to decayleptonically (trigger). Rate is large enough…. Cox, de Roeck, Khoze, Pierzchala, Ryskin, Stirling, Nasteva, Tasevsky-04

  11. without ‘clever hardware’: for H(SM)bb at 60fb-1 only a handful of events due to severe exp. cuts and low efficiencies, though S/B~1 . But H->WWmode at M>135 GeV. (B.Cox et al-06) enhanced trigger strategy & improved timing detectors (FP420, TDR) MSSM situation in the MSSM is very different from the SM SM-like > 4 generations:enhancedHbbrate (~ 5 times ) Conventionally due to overwhelming QCD backgrounds, the direct measurement of Hbb is hopeless The backgrounds to the diffractive H bb mode are manageable!

  12. for Higgs searches in the forward proton mode the QCD bb backgrounds are suppressed by Jz=0 selection rule and by colour, spin and mass resolution (M/M) –factors. There must be a god ! KMR-2000 (Mangano & Parke) ggqq

  13. The MSSM and more ‘exotic ‘scenarios If the coupling of the Higgs-like object to gluons is large, double proton tagging becomes very attractive • The intense coupling regime of the MSSM (E.Boos et al, 02-03) CP-violating MSSM Higgs physics(B.Cox et al . 03,KMR-03, J. Ellis et al.-05) Potentially of great importance for electroweak baryogenesis • an ‘Invisible’ Higgs(BKMR-04) • NMSSM(J. Gunion, J.Forshaw et al.)

  14. MSSM Higgs at High tanb • Neutral sector simplifies at high tanb • A and h/H become degenerate • Other scalar SM-like, low cross section • Only need to search for a single mass peak (f) • For the A and its twin h/H, at high tanb decays into bb (90%) and tt (10%) dominate • So, for example, won’t see enhancement in HWW* channel

  15. Four integrated luminosity scenarios HKRSTW, arXiv:0708.3052 [hep-ph] (bb, WW,- modes studied) • L = 60fb-1: 30 (ATLAS) + 30 (CMS): 3 yrs with L=1033cm-2s-1 2.L = 60fb-1, effx2: as 1, but assuming doubled exper.(theor.) eff. 3. L = 600fb-1: 300 (ATLAS) + 300 (CMS) : 3 yrs with L=1034cm-2s-1 4. L = 600fb-1,effx2: as 3, but assuming doubled exper.(theor.) eff. upmost ! We have to be open-minded about the theoretical uncertainties. Should be constrained by the early LHC measurements (KMR-08)

  16. New Tevatron data still pouring

  17. Simulation : A.Pilkington Shuvaev et al-08

  18. A.G. Shuvaev & KMR.arXiv:0806.1447 [hep-ph] Further improvement of the g-b misidentification probability 1.3%0.5% or even better. In the CEP environment gbb could/should be menagable

  19. CDM benchmarks Compliant with the Cold DarkMatter and EW bounds (EHHOW-07) Tevatron limits New bb-background(M. Tasevsky + HKRW TEVATRON PRELIMINARY 3 -discovery, P3- NUHM scenario LEP limit

  20. 5 -discovery, P3- NUHM scenario 3 -discovery, P4- NUHM scenario PRELIMINARY

  21. 3 -discovery, P3- NUHM scenario H PRELIMINARY

  22. Other BSM Scenarios ‘ Invisible ‘ HiggsB(KMR)-04 H • several extensions of the SM: fourth generation, • some SUSY scenarios, • large extra dimensions,… • (one of the ‘LHC headaches’ ) • the potential advantages of the CEDP – a sharp peak in the MM spectrum, mass determination, quantum numbers • strong requirements : • triggering directlyon L1 on the proton tigers • or rapidity gap triggers (forward calorimeters,.., ZDC)  Implications of fourth generation (current status: e.g.G.Kribs et.al,arXiv:0706.3718) For CEPenhanced Hbb rate (~ 5 times ), while WBF is suppressed.

  23. (J.R. Forshaw, J.F. Gunion, L. Hodgkinson, A. Papaefstathiou, A.D. Pilkington, arXiv:0712.3510)

  24. haa Low mass higgs in NMSSM: If ma < mB difficult (impossible) at standard LHC J. Gunion: FP420 may be the only way to see it at the LHC 150 fb-1

  25. Long Lived gluinos at the LHC P. Bussey et al hep-ph/0607264 Gluino mass resolution with 300 fb-1 using forward detectors and muon system The event numbers includes acceptance in the FP420 detectors and central detector, trigger… R-hadrons look like slow muons good for triggering Measure the gluino mass with a precision (much) better than 1%

  26. at 200 GeV: CED HWW rate – factor of ~7; at 120 GeV CED Hbb rate – factor of ~5.

  27. Experts claim that : Hints from B- factories Baryon asymmetry of the Universe Baryogenesis at the EW scale 4G is allowed by precision measurements 4G allows for the heavy Higgs 4G D0 data rule out a Higgs in a 4-generation scenario within 150-185 GeV mass range (CDF limits)

  28. for the light Higgs below 200 GeV

  29. + “ independent “ physicists Alberta, Antwerp, UT Arlington, Brookhaven, CERN, Cockroft, UC Davis, Durham, Fermilab, Glasgow, Helsinki, Lawrence Livermore, UCL London, Louvain, Kraków, Madison/Wisc, Manchester, ITEP Moscow, Prague, Rio de Janeiro, Rockefeller, Saclay, Santander, Stanford U, Torino, Yale. The earliest date for data taking is 2010

  30. CONCLUSION God Loves Forward ProtonS Forward Proton Taggingwouldsignificantlyextend the physics reachof the ATLASand CMS detectors by giving access to a wide range of exciting new physics channels. FPT has the potential to make measurements which are unique at LHC and may be challenging even at a ILC. For certain BSMscenarios theFPT may be the Higgs discovery channel. FPT offers a sensitive probe of the CP structure of the Higgs sector.

  31. Backup

  32. KMR: 0802.0177 Are the early LHC runs, without proton taggers, able to check estimates for pp  p+A+p ? gap gap Possible checks of: (i) survival factor S2:W+gaps, Z+gaps (ii) generalised gluon fg : gp Up Divide et Impera (iii) Sudakov factor T : 3 central jets (iv) soft-hard factorisation #(A+gap) evts (enhanced absorptive corrn)#(inclusive A) evts with A = W, dijet, U…

  33. Exclusive SM Higgs production b jets : MH = 120 GeV s = 2 fb (uncertainty factor ~2.5) MH = 140 GeV s = 0.7 fb WishList WW* : MH = 120 GeV s = 0.4 fb MH = 140 GeV s = 1 fb MH = 140 GeV :5-6 signal / O(3) background in 30 fb-1 H (with detector cuts) • The b jet channel is possible, with a good understanding of detectors and clever level 1 trigger ( μ-trigger from the central detector at L1 or/and RP(220) +jet condition) • TheWW channel is very promising : no trigger problems, better mass resolution at higher masses (even in leptonic / semi-leptonic channel), weaker dependence on jet finding algorithms, better PU situation • The  mode looks advantageous • If we see SM-like Higgs + p- tagsthe quantum numbers are0++ H

  34. suppressed enhanced The MSSM can be very proton tagging friendly The intense coupling regime is where the masses of the 3 neutral Higgs bosons are close to each other and tan  is large (E.Boos et al, 02-03) 0++ selection rule suppresses A production: CEDP ‘filters out’ pseudoscalar production, leaving pure H sample for study Well known difficult region for conventional channels, tagged proton channel may well be thediscovery channel,and is certainly a powerful spin/parity filter

  35. decoupling regime mA ~ mH150GeV, tan >10; h = SM intense coupling: mh ~ mA ~ mH ,WW.. coupl suppressed KKMR-04 • with CEDP: • h,Hmay be • clearlydistinguishable • outside130+-5 GeV range, • h,Hwidths are quite different

  36. Probing CP violation in the Higgs Sector Azimuthal asymmetry in tagged protons provides direct evidence for CP violation in Higgs sector ‘CPX’ scenario ( in fb) KMR-04 A is practically uPDF - independent CP odd active at non-zero t CP even (Similar results in tri-mixing scenaio (J.Ellis et al) )

  37. But not a simple replica in the signal rates

  38. small mass range  not obvious, needs further studies Thanks to Tim Tait for discussions

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