flavour physics at the high-energy frontier
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Flavour Physics at the High-Energy Frontier
FlaviaNet meeting in honour of Chris Sachrajda
John Ellis
Open Questions beyond the Standard Model
• What is the origin of particle masses?due to a Higgs boson? + other physics?solution at energy < 1 TeV (1000 GeV)
• Why so many flavours of matter particles?mixing and CP violation?
• Unification of the fundamental forces?at very high energy ~ 1016 GeV?probe directly via neutrino physics, indirectly via masses, couplings
• Quantum theory of gravity?(super)string theory: extra space-time dimensions?
LHC
LHC
LHC
LHC
High-pT Physics Meets Flavour
• The major particle physics objectives of the LHC– ATLAS, CMS, LHCb
• Good reasons to expect new physics at the TeV scale:– Higgs, naturalness, dark matter
• No clue where flavour physics originates
• What is flavour structure of TeV physics?
• How to reveal it?– Combine direct and indirect approaches
At what Energy is the New Physics?
A lot accessibleto the LHC
Some accessibleonly indirectly
Dark matter
Origin of mass
Where is the physics of flavour?
The Dogs that did (not) Bark
• In the quark sector:– CKM model describes perfectly (?) the available
data on quark mixing and CP violation– Passes consistency tests
• In the lepton sector:– MNS model describes neutrino mixing– No consistency tests– Muon anomalous magnetic moment may suggest
new physics at the TeV scale
Flavour and CP Violation
- CKM model successful atpresent
- A pillar of the Standard Model
- What lies beyond it?
Quo Vadisg - 2?
• Older e+e- data show discrepancy– now 3.4
• Disagreement with decay data– Discrepancy ~ 2
• New BABAR e+e- data agree poorly with previous e+e- data– Intermediate between e+e- and
decay data
• Combination with previous e+e- data yield discrepancy ~ 3.1
Astronomers tell us that most of the matter in the universe is invisible
We will look for it
with the LHC
Dark Matter in the Universe
Astronomers saythat most of thematter in theUniverse isinvisible Dark Matter
LSP ? LKP ? LTP ?
We shall look for them with the
LHC
Dark Matter in the Universe
Relics leaving thermal equilibrium in early Universeprovide cold dark matter if mass ~ (2.7 K Mplanck)1/2 ~ TeV
• Particles + spartners
• 2 Higgs doublets, coupling μ, ratio of v.e.v.’s = tan β• Unknown supersymmetry-breaking parameters:
Scalar masses m0, gaugino masses m1/2, trilinear soft couplings Aλ, bilinear soft coupling Bμ
• Assume universality? constrained MSSM = CMSSMSingle m0, single m1/2, single Aλ, Bμ: not string?
• Not the same as minimal supergravity (mSUGRA)• Gravitino mass, additional relations
m3/2 = m0, Bμ = Aλ – m0
Minimal Supersymmetric Extension of Standard Model (MSSM)
Minimal Flavour Violation (MFV)
• All squark mixing due to CKM matrix• Universal scalar masses at high scale for
sparticles with same quantum numbers• Parametrization:
• Maximally CP-violating MFV (MCPMFV) model has 19 parameters, of which 6 violate CP:
• Often assume universal ImMa, ImAf, but non-universality compatible with MFV: MCPMFV
JE + Lee + Pilaftsis: arXiv 0708.2079
Effects of CP Phases in MCPMFV
Renormalization
of phases Ino masses
Heavy Higgs masses
Bs mixing
J.E. + Lee + Pilaftsis: arXiv:0708.2078
Effects of CP Phases in MCPMFV
Bs
b s
Bu
Different
regions
allowed for
different
phases … … and hence
ACP in
b sJ.E. + Lee + Pilaftsis: arXiv:0708.2078
• Expand scalar mass2 matrices in complete basis derived from Yukawa couplings:
where:
• Use RGEs to study magnitudes in MCPMFV• Use data to constrain coefficients
SupersymmetricFlavour Geometry
JE + Hodgkinson +Lee + Pilaftsis: arXiv 0911.3611
Current Constraints on CMSSM
WMAP constraint on relic density
Excluded because stau LSP
Excluded by b s gamma
Preferred (?) by latest g - 2
Assuming the lightest sparticleis a neutralino
JE + Olive + Santoso + Spanos
Non-Universal Scalar Masses
• Different sfermions with same quantum #s?e.g., d, s squarks?disfavoured by upper limits on flavour-
changing neutral interactions
• Squarks with different #s, squarks and sleptons?disfavoured in various GUT models
e.g., dR = eL, dL = uL = uR = eR in SU(5), all in SO(10)
• Non-universal susy-breaking masses for Higgses?No reason why not!
NUHM
NUHM1
Best-Fit Spectra
CMSSM
O.Buchmueller, JE et al: arXiv:0808.4128
Spectra with likely Ranges
O.Buchmueller, JE et al: arXiv:0907.5568
Likelihood Function for Higgs Mass
CMSSM NUHM1
O.Buchmueller, JE et al: arXiv:0907.5568
How Soon Might the CMSSM be Detected?
O.Buchmueller, JE et al: arXiv:0808.4128
How Soon Might the NUHM1 be Detected?
O.Buchmueller, JE et al: arXiv:0808.4128
g - 2 b s
Sensitivities to Constraints
O.Buchmueller, JE et al: arXiv:0808.4128
What Happens if g - 2 Dropped?
Solid lines: with g - 2
Dashed lines: without g - 2
Focus-point still disfavoured, e.g., by mWO.Buchmueller, JE et al: arXiv:0907.5568
NUHM1CMSSM
Correlation between Gluino & Squark Masses
CMSSM NUHM1
O.Buchmueller, JE et al: arXiv:0907.5568
Likelihood Function for Bs +-
CMSSM NUHM1
O.Buchmueller, JE et al: arXiv:0907.5568
Standard Model prediction
Can the LHC find heavier Higgs Bosons?
CMSSM NUHM1
O.Buchmueller, JE et al: arXiv:0907.5568
Accessiblewith LHC
First 2009 Beam Circuits:Friday Nov. 20th @ 8.15pm
First LHC Collision in ATLAS
Two-Jet Event in CMS
Collision in LHCb
Colliding Beams @ 900 GeV
First LHC Physics Paper from ALICE
No Higgs yet!
Pseudo-rapidity distribution invariant mass distribution
No Supersymmetry
yet!
TPC
ITS
TOF
34
Towards Heavy Flavours in ALICE
Towards Heavy Flavours in ATLAS
SPC263, December 14, 2009 36
Towards Heavy Flavours in CMS
Ks
Towards Heavy Flavours in LHCb
Ks
Without
VELO
With
VELO
Colliding Beams @ 2.36 TeV
First 2.36 TeV Collision in ATLAS
No Black Holes yet!CMS 4-Jet Event @ 2.36 TeV
pT(m1) = 3.6 GeV, pT(m2) = 2.6 GeV, m(mm)= 3.04 GeVpT(m1) = 3.6 GeV, pT(m2) = 2.6 GeV, m(mm)= 3.04 GeV
CMS Experiment at the LHC, CERNDate Recorded: 2009-12-14 04:46 CETRun/Event: 124120/5686693Candidate Dimuon Event at 2.36 TeV
Even Heavier Flavour in CMS?
16 Bunches per Beam
Elastic Scattering Cross Sections
NUHM1CMSSM
O.Buchmueller, JE et al: arXiv:0907.5568
Likelihood Function for Spin-Independent Dark Matter Scattering
CMSSM NUHM1
O.Buchmueller, JE et al: arXiv:0907.5568
Conversation with Mrs Thatcher: 1982
What do you do?
Think of things for the experiments to look
for, and hope they find something different
Wouldn’t it be better if they
found what
you predicted?
Then we would not learn anything!
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