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New Physics with Forward Protons at the LHC

New Physics with Forward Protons at the LHC. V.A. K hoze ( IPPP, Durham & Rockefeller U. & PNPI ). (Based on works of extended Durham group). . main aims: to overview the ( very ) forward physics programme at the LHC;

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New Physics with Forward Protons at the LHC

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  1. New Physics with Forward Protons at the LHC V.A. Khoze ( IPPP, Durham & Rockefeller U. & PNPI) (Based on works of extended Durham group)  main aims:to overview the (very) forward physics programme at the LHC; to show that the Central Exclusive Diffractive Processes may provide an exceptionally clean environment to study SM & to search for and to identify the nature of, New Physics at the LHC; to discuss the new Exclusive results at the Tevatron; to attract new members to the Exclusive Forward Club.     H

  2. 4. The ‘standard candle’ processes( experimental checks at the Tevatron). 5. Prospects for CED Higgs production. 6. Other BSMscenarios, ‘Exotics’. 7. Conclusion.

  3. 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 ~10-15% at best) • 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! with a bit of personal flavour 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

  4. HPS ATLAS FP ALICE , LHCb

  5. A BIT OF HISTORY Full AcceptanceDetector – J. Bjorken (1991) FELIXLOI (1997) TOTEMLOI (1997) TOTEMTDR (2004) June 2000

  6. 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) • QCD test reactions, dijet P 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

  7. The basic ingredients of the Durhamapproach(KMR 1997-2009)  RGsignature for Higgs huntingDKT-1987. Rescattering effects-DKS-1992. Developed, clearly formulated and promoted by Bjorken(1992-93) Original idea pppHp – SJBrodsky (<1990). TCV- CMS-2007 + …. h • Main requirements: • inelastically scattered protons remain intact • active gluons do not radiate in the course of evolution up to the scale M • <Qt> >>/\QCDin order to go by pQCD book Further development (KKMR-01, BBKM-06,GLMM;KMR(07-09)) - 4 (CDPE) ~ 10 *  (incl)

  8. Production of Higgs particles in diffractive hadron hadron collisions. A.Schafer, O.Nachtmann and R..Schopf Phys.Lett.B249:331-335,1990.

  9. High price to pay for such a clean environment: σ (CEDP) ~ 10 -4 σ( inclus.) Rapidity Gapsshould survive hostilehadronicradiation damagesand ‘partonic pile-up ‘ symbolicallyW = S² T² Colour charges of the ‘digluon dipole’ are screened only at rd ≥ 1/ (Qt)ch GAP Keepers (Survival Factors) ,protecting RG against: the debris of QCD radiation with 1/Qt≥ ≥ 1/M(T) soft rescattering effects (necessitated by unitariy) (S) How would you explain this to your (grand) children ? Forcing two camels to go through the eye of a needle H P P

  10. (Khoze-Martin-Ryskin1997-2009) -4 (CDPE) ~ 10  (incl) New CDF results (dijets, , c) not so long ago: between Scylla and Charibdis: orders of magnitude differences in the theoretical predictions are now a history

  11. p p LHC as a High Energy  Collider KMR-02 QCD Sudakov Formfactor

  12. “soft” scattering can easily destroy the gaps S²absorption effects -necessitated by unitarity gap M Everybody’s ~ happy (KMR, GLMM, FHSW, Petrov et al, BH, GGPS, Luna...MCs) gap soft-hard factorizn conserved broken eikonal rescatt: between protons enhanced rescatt: involving intermediate partons Subject of hot discussions nowadays :S²enh

  13. Standard Candle Processes ‘Better to light a candle than to rant against darkness’ ( Confucius )

  14. CURRENT EXPERIMENTAL CHECKS ☻ Up to now the diffractive production data are consistent with K(KMR)S results Still more work to be done to constrain the uncertainties. Exclusive high-Et dijets CDF:data up to (Et)min>35 GeV ‘Factorization breaking’ between the effective diffractive structure functions measured at the Tevatron and HERA.CDF (PRD-00) The ratio of high Et dijets in production with one and two rapidity gaps. CDF (PRL-00) CDF results on exclusive charmonium CEP, (CDF, PRL-09) Energy dependence of the RG survival (D0, CDF). Central Diffractive Production ofγγ (…., )(CDF, PRL-07) ( in line with the KMRS calculations) ( 3 candidates & more candidates in the new data ) Leading neutrons at HERA (PRD-2008)    

  15. * * * Our 3 measurements are all in good agreement (factor “few”) with the Durham group predictions.

  16. Visualization of QCD Sudakov formfactor CDF PRD-2008 A killing blow to the wide range of theoretical models. CDF d

  17. arXiv:0902.1271 402 events Fit: 2 Gaussians + QED continuum. Masses 3.09, 3.68 GeV == PDG Widths 15.8,16.7 MeV=resolution. QED = generator x acceptance 3 amplitudes floating p p

  18. /KK mode as a spin-parity analyzer

  19. Khoze, Martin and Ryskin, Eur.Phys.J. C23: 311 (2002) ; KMR+Stirling hep-ph/0409037 Claim factor ~ 3 uncertainty ; Correlated to p+H+p 36 fb H 3 candidates, 2 golden, 1 ? ? 36 fb  0.8 events New data, Lower threshold, possible “observation” to come(?) & SuperCHIC ! (HKRS-09)

  20. Dimuons: Upsilon Region CDF Run II Preliminary Trigger: μ+μ- |η|<0.6 , pT(μ) > 4 GeV/c Inclusive Search for/measurement of photoproduction of Y(1S),Y(2S),Y(3S) (not before seen in hadron-hadron) Invariant Mass 0 associated tracks pT(μμ) < 1.5 GeV/c CDF Run II Preliminary Y(1S) Status: analysis in progress. QED continuum check, but kinematics better constrained. Y : cf HERA (we resolve states) Can we see ? At most a few events, but BR’s not known. Only “existence proof” (& not yet). Y(2S) Y(3S)

  21. 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 troublesome areas of the parameter space: • intense coupling regime of MSSM, MSSM with CP-violation… • More surprises may arise in other SUSY • non-minimal extensions: NMSSM, charming Higgs, hidden Higgs,… • ‘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 . Current consensus on the LHC Higgs search prospects mH (SM) <157 GeV @95% CL Recall, 14 TeV,L=1034 - anticipated only in 2014 SPIN-PARITY

  22. 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 Yukawa coupl.) conventionally- • (gg)CED bb inLO ; NLO,NNLO, b- masseffects – controllable. • For some scenariosCEPmay becomeadiscovery channel! • (SM Higgs (if exists) will be discovered by the standard methods.) •  A handle on the overlap backgrounds- Fast Timing Detectors (10 ps timing or better). • New leverage –proton momentum correlations (probes of QCD dynamics , CP- violation effects…) H BSM 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 CEP will be particularly useful !

  23. 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 ggqq

  24. without ‘clever hardware’: for H(SM) at 60 fb-1 only a handful of events due to severe exp. cuts and low efficiencies, though S/B~1 . enhanced trigger strategy & improvedtiming detectors (FP420, TDR) MSSM Situation in the MSSM is very different from the SM SM-like > Conventionally due to overwhelming QCD backgrounds, the direct measurement of Hbb is hopeless The backgrounds to the diffractive H bb mode are manageable!

  25. The MSSM and more ‘exotic ‘scenarios If the coupling of the Higgs-like object to gluons is large, double proton tagging becomes very attractive • Theintense couplingregime of theMSSM (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 Triplet Higgs bosons (CHHKP-2009) Fourth Generation Higgs (HKRTW-08,09)  NMSSM(J. Gunion, et al.) Invisible’ Higgs(BKMR-04) There isNO experimental preference for a SM Higgs. Any Higgs-like boson is very welcome !

  26. Higgs spin-parity determination HKRTW-09

  27. (S.Heinemeyer, VAK, M.Ryskin, W.J.Stirling, M.Tasevsky and G.Weiglein 07-08)

  28. New Tevatron data still pouring HKRSTW-07

  29. HKRSTW-07

  30. (bb, WW,- modes studied) We have to be open-minded about the theoretical uncertainties. Should be constrained by the early LHC measurements (KMR-08)

  31. NEW DEVELOPMENT Compliant with the Cold DarkMatter and EW bounds

  32. Simulation : A.Pilkington

  33. CDM benchmarks Abundance of the lightest neutralinio in the early universe compatible with the CDM constraints as measured by WMAP. The MA – tan planes are in agreement with the EW and B-physics constraints

  34. B(H) is suppressed

  35. CDF & D0

  36. At 60 fb-1 : for M=120 GeV , ~25 bb events; for M=220 GeV, ~ 50 WW events; favourable bgs

  37. Current status (HKRTW-09)

  38. New approach to studyheavy quarkoniaand new charmonium-like states (work together with L. Harland-Lang, M.Ryskin and W.J. Stirling) of interest for ALICE & LHCb CEP

  39. FNAL, E288 (spins- still unconfirmed) (Currently no complete theoretical description of onium properties.) (Still puzzles) (BABAR (2008) The heaviest and most compact quark-antiquark bound state in nature 47

  40. CONCLUSION God Loves Forward Protons ForwardProtonTaggingwouldsignificantlyextend the physics reachof the LHC 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 sometimes 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.

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