Common Benchmarks for FCC Physics John Ellis King’s College London & CERN @ FCC-ee/TLEP7 Workshop
Dec 17, 2015
Common Benchmarks forFCC Physics
John Ellis
King’s College London & CERN
@ FCC-ee/TLEP7 Workshop
Overall coordination: JE, Christophe Grojean– Match theory predictions to FCC-ee experimental precisions
– How to discover new physics in precision measurements,
in rare decays (Z, W, t, H, b, c, t, …), in rare or invisible processes
– Set up the framework for global fits and understand the complementarity with other colliders (LHC, FCC-hh, in particular)
Model Building and New Physics
Andreas Weiler
Precision EW calculations
Sven Heinemeyer
Global Analysis, Combination, Complementarity
JE
QCD and gg Physics
(Joint exp/th)Peter Skands
Flavour Physics(Joint exp/th)
Jernej Kamenik
Synergy with FCC-hh physics
Linear collider physics,LEP physicsHF physics
Phenomenological Working Groups
Towards Benchmarks for FCC Studies
• Higgs physics:– precision studies– higher-dimensional operators,
composite Higgs– rare and exotic decays– multiple Higgs production– extra Higgs bosons
• EW/SM precision issues– parameter measurements (mt, mW)
– higher-order EW corrections– 3 and 4 gauge boson (anomalous)
couplings– top (anomalous) couplings
• New physics related to EWSB:– WW scattering– supersymmetry– extra dimensions– composite models
• Rare flavour-changing processes:– Rare H decays– Rare Z decays– Rare top decays– charm/bottom flavor studies– lepton-flavour violation
• Extensions of the SM:– extra vector-like fermions– SU(2)R models
– leptoquarks
• Interface with cosmology:– dark matter– baryogenesis– right-handed/(almost) sterile
neutrinos
• QCD:– Perturbation theory– Modelling final states
Proposed physics topics to be used in the study of
synergy/complementarity among experiments at FCC-hh/ee/eh
Alain, Patrick, Michelamneglo, John + …?
LHC
HL-LHC
FCC-ee
FCC-hh (eh)
The Twin Frontiers of FCC-ee Physics
Precision Measurements • Springboard for
sensitivity to new physics
• Precision H studies• Precision Z studies• Theoretical issues:
– Higher-order QCD– Higher-order EW– Mixed QCD + EW
Rare Decays• Direct searches for new
physics• Many opportunities• Z: 1012
• b, c, τ: 1011
• W: 108
• H: 106
• t: 106
Precision FCC-ee Measurements
Precision Higgs Precision Electroweak
Possible FCC-ee Precision Measurements
What else is there?
Supersymmetry• Successful prediction for Higgs mass
– Should be < 130 GeV in simple models
• Successful predictions for couplings– Should be within few % of SM values
• Naturalness, GUTs, string, … (???)
p-value of simple models ~ 5% (also SM)
2012 20/fb
Scan of CMSSM
Buchmueller, JE et al: arXiv:1312.5250
Confronted with likelihood analysis of CMSSM
LHC Reach for CMSSM Susy
O. Buchmueller, JE, K. de Vries et al.
H to WW constraint on (m0, m1/2) plane in CMSSM:All points within one current σ of low-mass best-fit value
Impact of LHC Precision H on CMSSM
H to WW
O. Buchmueller, JE, K. de Vries et al.
H to WW constraint on (m0, m1/2) plane in CMSSM:Points within one, two, three TLEP σ of low-mass best-fit value
Impact of FCC-ee Precision H on CMSSM
H to WW
O. Buchmueller, JE, K. de Vries et al.
Estimate of (m0, m1/2) in CMSSM on basis ofprecision H measurements with low-mass best-fit central values
O. Buchmueller, JE, K. de Vries et al.
Impact of FCC-ee Precision H on CMSSM
ΓZ constraint on (m0, m1/2) plane in CMSSM:All points within one current σ of low-mass best-fit value
Impact of LEP Precision Z on CMSSM
ΓZ
O. Buchmueller, JE, K. de Vries et al.
ΓZ constraint on (m0, m1/2) plane in CMSSM:Points within one, two, three TLEP σ of low-mass best-fit value
Impact of FCC-ee Precision Z on CMSSM
ΓZ
O. Buchmueller, JE, K. de Vries et al.
Estimate of (m0, m1/2) in CMSSM on basis ofprecision Z measurements with low-mass best-fit central values
Impact of FCC-ee Precision Z on CMSSM
O. Buchmueller, JE, K. de Vries et al.
One-dimensional likelihood functions in CMSSM ifprecision measurements with low-mass best-fit central values:
compare masses with LHC measurements,
Test SUSY at the loop level
Impact of FCC-ee Precision on CMSSM
O. Buchmueller, JE, K. de Vries et al.
Comparison with LHC Measurement
• Consider squark and gluino pair production at low-mass best-fit point
• Simulate with PYTHIA + DELPHES
• Estimate 5 to 15% jet energy resolution• Assume 300/fb @ LHC @ 13 TeV• Fit data with template: estimated mass
resolution ~ 10 to 15%• Overall mass uncertainty ~ 20%• Test SUSY at the loop level
O. Buchmueller, JE, J. Marrouche et al.
Assume no SUSY @ HL-LHC:current precision measurements with high-mass best-fit values
Impact of HL-LHC on CMSSM
O. Buchmueller, JE, K. de Vries et al.
One-dimensional likelihood functions in CMSSM ifprecision measurements with high-mass best-fit central values:
Predict masses for FCC-pp measurements
Impact of FCC-ee Precision on CMSSM
O. Buchmueller, JE, K. de Vries et al.
What Parts of High-Mass CMSSM Parameter Space are Allowed?
• Imposing dark matter density constraint
• Focus-point strip:– A0 ~ 0, large m0/m1/2
• Extends to m1/2 ~ 4 TeV
• Neutralino has Higgsino mixture
• Truncated by mh
O. Buchmueller, JE, K. Olive et al.
Towards a ‘no-lose’ theorem for FCC-hh
HE-LHC
LHC 3000
LHC 300
LHC 8 TeV
• Imposing dark matter density constraint
• Stop coannihilation strip– A0 ~ 3 m0, large m0/m1/2
• Extends to m1/2 ~ 13 TeV
• Very small mass difference: mstop – mχ
• mh very uncertain
What Parts of High-Mass CMSSM Parameter Space are Allowed?
HE-LHC
LHC 3000
LHC 300
LHC 8 TeVO. Buchmueller, JE, K. Olive et al.
Towards a ‘no-lose’ theorem for FCC-hh
• Limited range compatible with mh
• Current precision EWPO measurements insensitive
Exploring the Focus-Point Strip
O. Buchmueller, JE, K. Olive et al.
• Compatible with LHC measurement of mh
• May extend to mχ = mstop ~ 6500 GeV
Exploring the Stop Coannihilation Strip
Current limits
(monojets), MET
LHC 300 (monojets), MET
HE-LHC (monojets), MET
LHC 3000 (monojets), MET
100 TeV (monojets), MET
Towards Benchmarks for FCC Studies
• Higgs physics:– precision studies– higher-dimensional operators,
composite Higgs– rare and exotic decays– multiple Higgs production– extra Higgs bosons
• EW/SM precision issues– parameter measurements (mt, mW)
– higher-order EW corrections– 3 and 4 gauge boson (anomalous)
couplings– top (anomalous) couplings
• New physics related to EWSB:– WW scattering– supersymmetry– extra dimensions– composite models
• Rare flavour-changing processes:– Rare H decays– Rare Z decays– Rare top decays– charm/bottom flavor studies– lepton-flavour violation
• Extensions of the SM:– extra vector-like fermions– SU(2)R models
– leptoquarks
• Interface with cosmology:– dark matter– baryogenesis– right-handed/(almost) sterile
neutrinos
• QCD:– Perturbation theory– Modelling final states
Proposed physics topics to be used in the study of
synergy/complementarity among experiments at FCC-hh/ee/eh
Alain, Patrick, Michelamneglo, John + …?