Download Beyond the Standard Model - Southampton High Energy Physics

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)
LHC
• Why so many flavours of matter particles?
mixing and CP violation?
LHC
• Unification of the fundamental forces?
at very high energy ~ 1016 GeV?
probe directly via neutrino physics, indirectly via masses,
couplings
LHC
• Quantum theory of gravity?
(super)string theory: extra space-time dimensions?
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?
Dark matter
Where is the physics of flavour?
Origin of mass
A lot accessible
to the LHC
Some accessible
only indirectly
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 at
present
- A pillar of the
Standard Model
- What lies
beyond it?
Quo Vadis
g - 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+edata yield discrepancy ~ 3.1 
Dark
Matterininthe
theUniverse
Universe
Dark Matter
Astronomers say
that
most of tell
the
Astronomers
matter
in theof the
us that most
Universe
is
matter in the
universe is
invisible
invisible
Dark
Matter
LSP ? LKP ? LTP ?
We will look for it
We shall look for
with the
LHC
them
with
the
LHC
Relics leaving thermal equilibrium in early Universe
provide cold dark matter if mass ~ (2.7 K  Mplanck)1/2 ~ TeV
Minimal Supersymmetric Extension of
Standard Model (MSSM)
• 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 = CMSSM
Single 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 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 nonuniversality compatible with MFV: MCPMFV
JE + Lee + Pilaftsis: arXiv 0708.2079
Effects of CP Phases in MCPMFV
Renormalization
of phases
Heavy Higgs
masses
J.E. + Lee + Pilaftsis: arXiv:0708.2078
Ino
masses
Bs
mixing
Effects of CP Phases in MCPMFV
Bs  
Different
regions
allowed for
different
phases …
b  s
J.E. + Lee + Pilaftsis: arXiv:0708.2078
Bu  
… and
hence
ACP in
b  s
Supersymmetric
Flavour Geometry
• Expand scalar mass2
matrices in complete
basis derived from
Yukawa couplings:
where:
• Use RGEs to study magnitudes in MCPMFV
JE + Hodgkinson +Lee +
• Use data to constrain coefficients
Pilaftsis: arXiv 0911.3611
Current Constraints on CMSSM
Assuming the
lightest sparticle
is a neutralino
Excluded because stau LSP
Excluded by b  s gamma
WMAP constraint on relic density
Preferred (?) by latest g - 2
JE + Olive + Santoso + Spanos
Non-Universal Scalar Masses
• Different sfermions with same quantum #s?
e.g., d, s squarks?
disfavoured by upper limits on flavourchanging 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
Best-Fit Spectra
CMSSM
O.Buchmueller, JE et al: arXiv:0808.4128
NUHM1
Spectra with likely Ranges
O.Buchmueller, JE et al: arXiv:0907.5568
Likelihood Function for Higgs Mass
CMSSM
O.Buchmueller, JE et al: arXiv:0907.5568
NUHM1
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
Sensitivities to Constraints
g - 2
O.Buchmueller, JE et al: arXiv:0808.4128
bs
What Happens if g - 2 Dropped?
CMSSM
NUHM1
Solid lines: with g - 2
Dashed lines: without g - 2
Focus-point still disfavoured, e.g., by mW
O.Buchmueller, JE et al: arXiv:0907.5568
Correlation between
Gluino & Squark Masses
CMSSM
O.Buchmueller, JE et al: arXiv:0907.5568
NUHM1
Likelihood Function for Bs +CMSSM
Standard Model prediction
O.Buchmueller, JE et al: arXiv:0907.5568
NUHM1
Can the LHC find heavier Higgs Bosons?
CMSSM
Accessible
with LHC
O.Buchmueller, JE et al: arXiv:0907.5568
NUHM1
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!
Towards Heavy Flavours in ALICE
ITS
TPC
TOF
34
Towards Heavy Flavours in ATLAS
Towards Heavy Flavours in CMS
SPC263, December 14, 2009
36
Towards Heavy Flavours in LHCb
Ks
Ks
With
VELO
Without
VELO
L
L
Colliding Beams @ 2.36 TeV
First 2.36 TeV Collision in ATLAS
No Black Holes yet!
CMS 4-Jet Event @ 2.36 TeV
Even Heavier Flavour in CMS?
CMS Experiment at the LHC, CERN
Date Recorded: 2009-12-14 04:46 CET
Run/Event: 124120/5686693
Candidate Dimuon Event at 2.36 TeV
pT(m1) = 3.6 GeV, pT(m2) = 2.6 GeV, m(mm)= 3.04 GeV
16 Bunches per Beam
Elastic Scattering Cross Sections
CMSSM
O.Buchmueller, JE et al: arXiv:0907.5568
NUHM1
Likelihood Function for SpinIndependent Dark Matter Scattering
CMSSM
O.Buchmueller, JE et al: arXiv:0907.5568
NUHM1
Conversation with Mrs Thatcher: 1982
What do you do?
Think of things for the
experiments to look
for, and hope they find
something different
Then we would not
learn anything!
Wouldn’t it be
better if they
found what
you predicted?