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Comparing A ccelerator and direct Dark Matter searches

Comparing A ccelerator and direct Dark Matter searches. WIMPS: what can we say about their properties ? possible origins ?  many models What is an effective theory ? Detecting DM from missing momentum at colliders : LEP, Tevatron , LHC Validity of effective theory.

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Comparing A ccelerator and direct Dark Matter searches

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  1. ComparingAccelerator and direct DarkMattersearches • WIMPS: • whatcanwesay about theirproperties? possible origins?  manymodels • Whatis an effective theory? • Detecting DM frommissingmomentumatcolliders: • LEP, Tevatron, LHC • Validity of effective theory • Some references: • Bai, Fox and Harnik, 1005.3797v2 • P. Fox et al., 1103.0240 • J. Goodman et al., 1008.1783, 1111.2359 • G. Busoni et al., 1307.2253, 1402.1275 • O. Buchmueller et al., 1308.6799 • M. Papucci et al., 1402.2285 • KICP workshop 2013: https://kicp-workshops.uchicago.edu/DM-LHC2013/presentations.php G. Azuelos Dark Matter workshop - Montreal

  2. Properties of WIMPS Dark Matter workshop - Montreal In earlyuniverse, WIMPS are in thermal equilibrium and annihilateuntil the densityistoolow  freeze-out Somepossibilities: LSP: neutralinos, gravitinos LKP: Kaluza-Klein state in Universal Extra dimensions LTP: Little Higgs with T parity also, in Technicolor, composite Higgs models Higgs portal Z’ portal fermion portal  useful to have a model-independentapproach In colliderexperiments: non-interacting, invisible particles missing ET

  3. Effective theories W Classic example: Fermi theory: Weak interaction is well approximated, in nuclear physics, by a contact interaction, when, in fact, it is an exchange of a heavy particle Dark Matter workshop - Montreal Assume new physics at some high energy scale L Energy scale at which measurement is performed: Q  Observed effect of new physics is small and needs to be calculated at 1st order only

  4. Effective approximation Propagator of the heavy particle: valid as long as (weak contact coupling) c q M c q (f = scalar mediator) Dark Matter workshop - Montreal

  5. Translate to Direct Detection time c q M c q Dark Matter workshop - Montreal

  6. Different kinematics Dark Matter workshop - Montreal

  7. Wimpsinteractingwithmatter c c c c c q c c h,H Z q q q q q q q c Dark Matter workshop - Montreal Assumingweak interactions (neutralinos): spin-independent: spin-dependent

  8. spin-dependent cross sections arXiv:1005.3797v2 atTevatron proton neutron Bai, Fox and Harnik Dark Matter workshop - Montreal

  9. Light mediator momentum and spin-dependent model arXiv:1005.3797v2 Bai, Fox and Harnik Dark Matter workshop - Montreal

  10. LEP shines light on Dark Matter 4 effective operators • single photon • cm energy ~ 200 GeV • central: 45o < q < 135o • forward: 12o< q < 32o • v. forward: 3.8o< q< 8o arXiv:1103.0240v1 simulated conditions, accounting for efficiencies as function of angle and resolutions P. Fox et al. Dark Matter workshop - Montreal

  11. DM nucleon scattering cross section arXiv:1103.0240v1 P. Fox et al. • also considered… • if lepton coupling only • limits on annihilation • lighter mediator effects strongconstraints on spin-dependentatlow mass: no A2dependence Dark Matter workshop - Montreal

  12. Operators Manycurvesobtained for the limits on L and for limitsderived on nucleon cross sections for the differentoperators arXiv:1008.1783v2 J. Goodman et al. Dirac Complexscalars Real scalars Dark Matter workshop - Montreal

  13. reach at colliders, in EFT spin-independent arXiv:1008.1783v2 J. Goodman et al. spin-dependent Dark Matter workshop - Montreal

  14. LHC ATLAS 1210.4391 Dark Matter workshop - Montreal

  15. Validity condition of EFT • Definition: ; Typically expect • condition for perturbativity: • mediator heavier than WIMP: • truncation of propagator expansion: • s-channel: arXiv:1307.2253 G. Busoni et al. The lower Q, the better the EFT approximation Dark Matter workshop - Montreal

  16. Momentum transfer Q k p1 p3 p2 p4 arXiv:1307.2253 G. Busoni et al. Dark Matter workshop - Montreal

  17. RL Fraction of cross section for which Q < L : for scalar operator: arXiv:1307.2253 G. Busoni et al. Dark Matter workshop - Montreal

  18. RL for scalar operator: arXiv:1307.2253 G. Busoni et al. Dark Matter workshop - Montreal

  19. Compared to ATLAS arXiv:1402.1275 G. Busoni et al. Dark Matter workshop - Montreal

  20. rUV/eff Ratio of cross sections obtained with UV completed theory (s-channel scalar mediator) and with EFT : arXiv:1307.2253 G. Busoni et al. The smalletpT and mc are, the better the EFT approximation. Dark Matter workshop - Montreal

  21. Beyond Effective Field Theory at the LHC • EFT is valid if • cross section enhanced if mediator is on-shell, for example • Consider CMS monojet analysis, as basis (7 and 8 TeV analyses) • Use Monte Carlo (MCFM 6.6) to simulate dark matter monojet process • includes full effects of mediator propagator and width, in s-channel • consider axial-vector and vector operators only: • apply CMS cuts • one hard jet: pT > 100 GeV • signal regions (best of their signal regions) • parton level cuts, with geometric acceptance • background simulated with MadGraph: • pythia showering and PGS detector simulation • compared results with CMS to validate their MC analysis arXiv:1308.6799 O. Buchmueller et al., Dark Matter workshop - Montreal

  22. Simplified model s-channel axial-vector interaction: applies also to Majorana DM, and more interesting spin-dependent limits EFT OK 2.5 TeV resonant production of mediator EFT OKwithin 20% resonant production of mediator EFT valid if M >> Q • Q > 500 GeV when pT(j) > 100 GeV, Etmiss > 400 GeV • find condition: M > 2.5 TeV Dark Matter workshop - Montreal

  23. Region 1: Very high mediator mass: EFT OK arXiv:1308.6799 O. Buchmueller et al., Dark Matter workshop - Montreal

  24. Region II : resonant enhancement • On-shell production of mediator if • production enhanced  EFT limit conservative arXiv:1308.6799 Region III for CMS conditions Region II for CMS conditions CMS EXO-12-048 PAS O. Buchmueller et al., see also Goodman & Shepherd, arXiv:1111.2359 Limit on L scales as ~ G-1/4 at the resonance peak Dark Matter workshop - Montreal

  25. Region III: very light mediator – EFT limit too strong • In the limit where the mediator is very light, • the cross section does not depend on its mass since • EFT assumes M is very large (and g small for the same L) arXiv:1308.6799 O. Buchmueller et al., Dark Matter workshop - Montreal

  26. Comparison to Direct Detection arXiv:1308.6799 O. Buchmueller et al., Dark Matter workshop - Montreal

  27. Recommendations and Conclusion • Validity of EFT depends a lot on the assumptions and parameters: • 4 parameters: • small dependence on width G in resonance region • LHC should provide limits on L in M-mcplane (in s-channel assumption?) • for few values of G/M Complementarity: M. Cahill-Rowley, 1305.6921 Dark Matter workshop - Montreal

  28. Extras Dark Matter workshop - Montreal

  29. tree level coupling to leptons only Dark Matter workshop - Montreal

  30. Assume coupling to leptons only Dark Matter workshop - Montreal

  31. Limits on Λ Dark Matter workshop - Montreal

  32. Upper limits on annihilation cross sections Dark Matter workshop - Montreal

  33. Annihilation cross section, compared to astronomicallimits LEP limitsbetterthan Fermi for low masses Dark Matter workshop - Montreal

  34. With different mediator masses strongdependence on width, if M > 2 mwimp, sinceitisproduced on-shell Dark Matter workshop - Montreal

  35. Wimp-Nucleus cross section Dark Matter workshop - Montreal

  36. Annihilation cross section Dark Matter workshop - Montreal

  37. Limits on L Bai, Fox and Harnik,arXiv:1005.3797 • monojetlimitsfrom CDF • ET(jet) > 80 GeV • Etmiss > 80 GeV • 2nd jet ET < 30 GeV • no add. jet with ET > 20 GeV Dark Matter workshop - Montreal

  38. spin-independent cross section Bai, Fox and Harnik,arXiv:1005.3797 proton very sensitive atlow masses tests alsocouplings to highergenerations Dark Matter workshop - Montreal need quark content of nucleon

  39. c c c c c q c c h,H Z q q q q q q q c http://www.worldscientific.com/doi/abs/10.1142/S0218301392000023?queryID=%24%7BresultBean.queryID%7D Dark Matter workshop - Montreal

  40. ATLAS 1210.4391 Dark Matter workshop - Montreal

  41. ATLAS 1210.4391 Dark Matter workshop - Montreal

  42. ATLAS 1210.4391 Dark Matter workshop - Montreal

  43. ATLAS mono-Z1404.0051 Dark Matter workshop - Montreal

  44. CMSEXO-12-048 PAS Dark Matter workshop - Montreal

  45. Bai, at DM workshop 2013 Dark Matter workshop - Montreal

  46. Bai, at DM workshop 2013 Dark Matter workshop - Montreal

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