Trouble with ww scattering: m ~ E2



Yüklə 5,16 Mb.
tarix31.08.2018
ölçüsü5,16 Mb.
#65576





Trouble with WW scattering: M ~ E2

  • Trouble with WW scattering: M ~ E2

  • uncontrollable infinities in loop diagrams

  • can be cancelled by

  • scalar exchange

  • with HWW couplings

  • Need new physics @ TeV scale









  • Quite consistent: Δχ2 ~ 1.5



Large Mh → large self-coupling → blow up at low-energy scale Λ due to

  • Large Mh → large self-coupling → blow up at low-energy scale Λ due to

  • renormalization

  • Small: renormalization

  • due to t quark drives

  • quartic coupling < 0

  • at some scale Λ

  • → vacuum unstable

  • Vacuum could be stabilized by Supersymmetry



Very sensitive to mt as well as MH

  • Very sensitive to mt as well as MH

  • Present vacuum probably metastable with lifetime >> age of the Universe



What is it?

  • What is it?

    • Higgs or …?
  • What else is there?

    • Supersymmetry …?
  • What next?

    • A Higgs factory or …?


Higgs field:

  • Higgs field:

  • <0|H|0> ≠ 0

  • Quantum loop problems







Rescale couplings: to bosons by a, to fermions by c

  • Rescale couplings: to bosons by a, to fermions by c

  • Standard Model: a = c = 1



Do couplings scale ~ mass? With scale = v?

  • Do couplings scale ~ mass? With scale = v?

  • Red line = SM, dashed line = best fit



ATLAS sees excess in γγ, CMS sees deficit

  • ATLAS sees excess in γγ, CMS sees deficit

  • Loop diagrams ~ Standard Model?



Higher-dimensional operators as relics of higher-energy physics?

  • Higher-dimensional operators as relics of higher-energy physics?

  • Operators constrained by SU(2) × U(1) symmetry:

  • Constrain using LHC +

  • Tevatron Higgs

  • measurements



Combine Higgs coupling measurements with constraints on anomalous triple-gauge boson couplings

  • Combine Higgs coupling measurements with constraints on anomalous triple-gauge boson couplings



Constraints from energy dependence of



Supersymmetry

  • Supersymmetry













To study the ‘Higgs’ in detail:

  • To study the ‘Higgs’ in detail:

  • The LHC

    • Rethink LHC upgrades in this perspective?
  • A linear collider?

    • ILC up to 500 GeV
    • CLIC up to 3 TeV
      • (Larger cross section at higher energies)
  • A circular e+e- collider: LEP3, TLEP

    • A photon-photon collider: SAPPHiRE
  • A muon collider









Predictions of current best fits in simple SUSY models

  • Predictions of current best fits in simple SUSY models

  • Current uncertainties in SM calculations [LHC Higgs WG]

  • Comparisons with

    • LHC
    • HL-LHC
    • ILC
    • TLEP
  • Don’t decide before LHC 13/4



A large circular tunnel

  • A large circular tunnel

    • Circumference ~ 80 to 100 km
  • Could accommodate TLEP and VHE-LHC

    • ECM up to 100 TeV with 15 Tesla magnets
  • Could be sited around Geneva

  • TLEP Study Group under way

  • Timely to study VHE-LHC





Yüklə 5,16 Mb.

Dostları ilə paylaş:




Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur ©genderi.org 2023
rəhbərliyinə müraciət

    Ana səhifə