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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 20041
Highlights from ICHEP 04
ICHEP 2004, BeijingNicola Coppola
Colloquium at NIKHEF
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
The Basis of Particle Physics
String theory
Cosmology
Future acceleratorsBarbieri2
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
QCD Works!
@ Tevatron
@ HERA
Klein
CrucialFor LHC
b productionLucchesi
3
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
World Summary of αS(MZ) July 2004
world average (MSbar, NNLO)
αS(MZ) = 0.1182 0.0027
cf. (2002) 0.1183 0.0027
Bethke , hep-ex/0407021
Stirling
4
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Summary of beauty data from HERA vs NLO QCD
Klein5
Data of increased accuracy are above but not inconsistent with QCD
Charm is 20% of F2.Beauty only 2% belowvalence quark region
First measurement of bottom structure function, uses b lifetime tagging.
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
More beauty data from HERA
Loizides6
2 times the statistic is already on tape, ready for analysis
First measurement of bottom using b lifetime tagging with new MVD.
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
NNLO pQCDCalculations
Parton splitting functions
W, Z cross sections
+ 7 pages! Moch, Vermaseren & Vogt
jetson
way
Stirling
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
QCD Calculations in String Approach
• Maximal helicity-violating (MHV) amplitudes as effective vertices in a new scalar graph approach
• use them with scalar propagators to calculate
– tree-level non-MHV amplitudes
– with both quarks and gluons
– … and loop diagrams!
• dramatic simplification: compact output in terms of familiar spinor products
• phenomenology? multijet cross sections at LHC, etc. underway
Cachazo, Svrcek & Witten
Stirling
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Particle Production RatiosWell described by simple thermodynamic model, T ~ lattice …
… but could these just be phase space and statistics?Dunlop 10
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Elliptic Flow: the Shape of the Interaction Region at RHIC
Anisotropic Flowx
yz
Peripheral Collisions
Reproduced well by hydrodynamic model
Shape parameter v2
but hydrodynamic model failsto reproduce HBT source size
Dunlop
11
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Hadron Elliptic Flows Scale with Quark Number
)3/p( v3 ~)p( vand )2/p( v2 ~)p( vpions,Except T2,qTB2,T2,qTM2,
Dunlop
12
– Clear separation into two classes: baryons and mesons
– Apparent scaling with number of constituent quarks in final-state hadron
y
x
py
px
)(tan,2cos 12
x
y
pp
v
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Jet Quenching @ RHIC …
… due to parton energy loss in QGP?
Dunlop Strong suppression of back-to-back correlations in central Au+Au
13
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
The State of Heavy-Ion Theory• A patchwork, with model parameters adjusted
independently for different observables.• Statistical equilibriation or phase space?• Hydrodynamical model: EOS vs realistic quark-gluon
calculations?• Source size as measured by HBT?• Parton energy loss: promising development!• Watch out for J/ψ suppression!• For compelling QGP claim, need quantitative estimates
of theoretical uncertainties Dunlop15
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Questions on Hadron Spectroscopy
• Do (which) pentaquarks exist?• Do other exotic hadrons exist?• What are the quark descriptions of the DsJ
(2317) and DsJ(2460)?• Does the DsJ(2632) exist (SELEX)?• What is the quark description of the X(3872)?• Interpretation of threshold reported states?• Fate of 12% rule in ψ’ decay (BES)?
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Some Sightings of the Θ+(1530) …
… but many negative searchesJin
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
(LEPS)
nK
Inconsistencies in Mθ and Γθ?
0SpK
Also width of θ+(1540)
- Two “positive” experiments:HERMES: Γθ = 17 9 2 MeV
ZEUS: Γθ = 8 4 MeV
K+N PWA indicates Γθ < 1 MeV
Jin
M(nK+)≠ M(pKs)?
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
How Significant are Negative Results?
• Compare with production of other baryons resonances
• Λ(1520) may not be most reliable guide
• Most positive results at lower energies
• Different production mechanisms for exotic baryons?
Jin
21
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Interpretations of θ+(1530) – if it exists
• Naïve non-relativistic quark model would need epicycles:
di/triquarks, P-wave ground state• Predicted in chiral soliton model:
fits data, predicts other exotic states• Existence requires confirmation:
a high-statistics, high-significance experiment• If it exists, θ+ spin & parity distinguish models
The stakes are high: the θ+(Ξ--, θc) may take us beyond the naïve quark model
← Based on idea thatquarks weigh << ΛQCD
Close
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
M()
BK X(3872)
Belle
Also reported in ωJ/ψ:mixed isospin would
→ mixing with D0D*0 molecule
Close
X(3872 ): Charmonium or D0D*0 “Molecular State”?
’J/
X(3872) 10σeffect
Belle, also CDF, D0
MeVMeVM
3.25.06.00.3872
at 90% C.L.
No D0D0 → unnatural spin-parity Jin
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M(J/ ) –M(J/ )
M(J
/
)
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
M=1859 MeV/c2
< 30 MeV/c2 (90% CL)
J/pp
0 0.1 0.2 0.33-body phase space acceptance
2/dof=56/56
acceptance weighted BW +3 +5
10 25
BES IIalso pΛ,pΛc, KΛ,
ππ,πΚ
Hadronic Threshold States
Quark description inadequate: need hadronic description? molecules, …?
Jin
24
M(pp)-2mp (GeV)
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Electroweak Physics
APV, E158compatible
with expectedrunning of α(Q2)
NuTeV:EW corrections - 1σ?
Strange sea - 1σ?ubar ≠ dbar - 1σ?
(NOMAD)
Teubert
Low Energy vs High Energy
25
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Top-Quark Mass: Run 1 Revisited D0: improved Run 1 value
) GeV 5.1 174.3 m (previous t
t tM M 2.4 % @
t
m 178.0 2.7(stat) 3.3New world average (Run 1 on
(syst) GeV 178.0 4.3 GeV
ly):
new
Implications for fit to Higgs mass …Denisov
FutureTevatronProspects
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
The Blue Band Plot Global electroweak fit – high Q2 data
Since Aachen EPS Summer 2003:new top mass increases mH by ~20 GeVnew 2-loop terms etc. increase mH by ~6 GeV
t
S Z
+ 69H - 4
2
5
H
m = 178.2 3.9 GeV(M ) = 0.1186 0.0027
m = 114 = 15.8/13 df (prob = 2
GeV
m < 260 GeV (6
95 )%)
% cl
(5)had Z Hfor (M ) = 0.02749 0.00012 m 129 GeVD Þ
2W H
from uncertainties of 2 (& leading 3)loops for M & sin (main ef'bl
fecueb
t fand'
or m )eff
new
Teubert
BES et al 27
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Pulls on Global Fit
Direct search limit
Higgs mass from individual measurements
How Good is the Global Electroweak Fit?
Heavy flavours ≠ leptons, mW
Teubert 28
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004Denisov, Barr
fb-1
1 year @1033
1 month @1033
1 year @1034
LHC: ATLAS
Values for single experiment
h → requiresexcellent low-pT lepton + tau jet trigger
tim
e
Looking for Standard-Model Higgs
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Klein
How good is the EW “Standard-Model”
30
-combined H1 and ZEUS-result consistent with 0
In the SM LH coupling `n isexcluded unless RH currents exist
Expect zero cross section at P=-1and linear dependence on P
HERA II: can now prescribepositron beam helicity also inep collider mode
Polarization dependence firmlyestablished for the first time
se+p®`n X
(Pe+=-1) = 0.2 ± 1.8 (stat) ± 1.6 (sys) pb
2dof
=5.4/4
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Flavour Physics: Some Questions
• Are the data on quark mixing described by the CKM model?
• Are there signatures of physics beyond the SM?• If not, why is new physics flavour-blind?• Why is neutrino mixing so different from quark
mixing?• Can they be related?
Sakai, Ali, Giorgi, Ligeti, Patera, Shipsey, Langacker, McGrew, Wang
31
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
New Determinations of Vus
CKM unitarity ‘crisis’ has disappeared
V us x
f +(0
)
•PDG02
Patera
32
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Just a reminder on CKM/CPV results
Is there room for NP?
Sakai, Ali, Giorgi, Ligeti33
First evidence for direct CPV in B decays
Paradigm change: look for corrections,rather than alternatives to CKM
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Rare KDecays
KL→0e+e-
KL→0+-
KS→0e+e-
KS→0+-
KL→0
Im t = A23
)0,1()0,0(
),(
The connection of the KL0e+e-() decays to t
needs work on ancillary modes
More handles on triangle
Results & prospectsfor K+ → π+νν
Bounds & prospectsfor KL
→ π0νν
KS → π0l +l-, π0γγimportant forKL → π0l +l-
Patera
35
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Neutrino Masses & Oscillations• First confirmed physics beyond SM• LSND? Waiting for MiniBooNE• (Near) bimaximal mixing ≠ quarks:
Is there a relation: θν+θc = π/4? Reactors for θ13? • Dirac or Majorana masses: seesaw?
Normal or inverted hierarchy? ββ0ν?• Holy Grail: CP violation via phase δ?
Indirect relation to cosmology via baryogenesis?• Search for violation of charged lepton numbers
Langacker
36
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
L/E Significance
Δχ2 (neutrino decay – oscillation) =11.4 3.4 σΔχ2 (neutrino decoherence – osc’n) =14.6 3.8 σ
Evidence for Neutrino Oscillation Patternfrom Super-Kamiokande & KamLAND
OscillationDecayDecoherence
Wang37
The dips in the data cannot be explained by other models
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
KamLAND
SK/SNO
sin2 is determined by SK/SNO
KamLAND consistent with SK/SNO
Wang
38
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
K2K confirms Super-KamiokandeK2K Rate suppression
and spectral distortion …
… agree with SK azimuthal distributionsand
L/E analysis
McGrew, Wang39
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Physics beyond the SM
• The most pressing issue is breaking EW symmetry
• Must be solved below 1 TeV energy• Would be a revolution in fundamental physics• Basis for any further theoretical speculations• Hints of grand unification: gauge couplings,
neutrino masses, but wait and see• String unification is still the dream
Barbieri
40
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Breaking Electroweak Symmetry
• Calculability principle: EW scale should be calculable in terms of other mass scale
• No quadratic divergences: supersymmetry ?or Higgs as pseudo-Goldstone boson ?
• Supersymmetry: also gauge unification and dark matter
• LEP data: some fine-tuning needed Barbieri
41
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Alternatives to Supersymmetry
• Interpretation of EW data?consistency of measurements? Discard some?
• Higgs + higher-dimensional operators?corridors to higher Higgs masses?
• Little Higgs modelsextra `Top’, gauge bosons, `Higgses’
• Higgsless modelsstrong WW scattering, extra D?
Barbieri
42
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Little Higgs Models• Embed SM in larger gauge group• Higgs as pseudo-Goldstone boson• Cancel top loop
with new heavy T quark
• New gauge bosons, Higgses• Higgs light, other new
physics heavy Not as complete as susy: more physics > 10 TeV
MT < 2 TeV (mh / 200 GeV)2
MW’ < 6 TeV (mh / 200 GeV)2
MH++ < 10 TeV
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004 44
zoomzoom
gμ - 2: e+e- Data vs τ Data
KLOE agrees with CMD-2: discard τ dataWhy the 10%
τ - e+e- discrepancy above ρ peak?
Largest contributions, errors from low energies
Teubert
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Weak contribution : aweak = + (15.4 ± 0.3) 10 –10
Hadronic contribution from higher order : ahad [( /)3] = – (10.0 ± 0.6) 10 –10
Hadronic contribution from LBL scattering: ahad [LBL] = + (12.0 ± 3.5) 10 –10
Updated Results for gμ - 2(693.4 ± 5.3 ± 3.5) 10 –10=(11 659 182.8 ± 6.3had ± 3.5LBL ± 0.3QED+EW) 10 –10=a
SM [e+e– ]
ahad [e+e– ]
2.7 standard deviations
= (25.2 ± 9.2) 10 –10a
exp – a SM
not yet published
not yet published
preliminary
BNL E821 (2004):a
exp = (11 659 208.0 5.8) 1010
Teubert45
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Sparticle mass measurements @ LHC
• Mass measurements from exclusive cascade decays
• Mass differences well measured– Typically limited by
detector performance• Of order 1%
• Error in overall mass scale– Unknown missing energy
• Of order 10%
ATLASSquark – neutralino1mass difference5 fb-1
q
qR~
qR~
q
p p
Barr //
46
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
l+
l- parton-level
-> Measure spin-1/2 nature of neutralino-2-> Also can measure scalar nature of slepton-> Success at several distinct points in parameter space
detector-level
Lepton+jet invariant massC
harg
e as
ymm
etry
spin-0
Even
tsMeasuring Sparticle Spin @ LHC
0* 1*
ATLAS
ATLAS
Barr //47
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
NLO QCD Calculations Needed for Extracting BSM signals
Stirling48
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
A Few Remarks on String Theory
• A very powerful tool, e.g., for QCD• Already solved many problems in Q. Gravity• Is it relevant to particle physics?• Can string theory explain the origin of the
Universe?• Could it replace inflation by a scalar field?• What is the landscape of string vacua?• Distinctive experimental signature: extra D? Liu
Stirling
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Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Particle Astrophysics and Cosmology
• What is the Dark Matter?• Is there Dark Energy?• Are there Ultra-High-Energy Cosmic
Rays beyond the GZK cutoff?• Was there inflation?• How did the Universe begin?
Binetruy
51
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Composition of the Cosmos
WIMPs
WMAP best fit
Binetruy52
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
WMAP+SN+HST
Concordance Cosmological ModelWMAP, Supernovae,Large-scale structures …
Barbiellini //, Ghirlanda et al
… and gamma-ray bursters?
53
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Candidates for Cold Dark Matter• Axion?• Lightest Supersymmetric Particle (LSP)?
neutralino? gravitino?accelerators vs non-accelerator expts?
• Lightest Kaluza-Klein Particle (LKP)?in models with universal extra dimensions
• Superheavy (metastable) Particle?‘WIMPzilla’ produced at inflation?decays responsible for UHECRs??
54
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Direct Search for Dark Matter- Look for elastic scatteringon nuclei in low-backgroundexperiment
- DAMA modulation signaldifficult to reconcile withother experiments, such asCDMS2
- Good prospects forimprovement by factor ~ 20
- Starting to reach regionexpected in models
Binetruy55
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
~2 degrees around the galactic center
EGRET data
Annihilation channel W+W-
Mχ =80.3 GeVbackground model (Galprop)WIMP annihilation (DarkSusy)
Total Contribution
Gamma Rays from Neutralino Annihilations?
- Uncertainties incosmic-ray bkgrd- Also in signalnormalization
Morselli, Sander // 56
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Neutralino Annihilations inside Sun?
Look forχχ→ν→μ
Future
Present
57
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Questions on Future Accelerators
• What do we want?• How can we involve a diversity of regions?• How can we ensure diversity of facilities?• Can we work together to get them approved?• Can we build them?• Can we do experiments with them?• Will they answer all our questions?• How can we ensure access to them? Lüth
Brau
Yokoya
Dorfan
Miller
Barbieri
58
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Motivations for Future Colliders• Physics AND cosmology make us expect
strong new signals at the scale of 1 TeV• Physics case for LHC has been made and
accepted: It will look into the whole region where new physics should be
• Physics case for the TeV ILC has been made.• Physics cases for CLIC (and Larger HC?) will
follow results from LHC (and TeV ILC)
Miller
59
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Tasks for the TeV ILC
• Measure mt to < 100 MeV• If there is a light Higgs of any
kind, pin it down: Does it have standard model couplings? What is its precise mass?
• If there are extra light particles: Measure mass and properties
• If LHC sees nothing new below ~ 500 GeV:
Look for indirect signatures
Miller
60
MeVmmR
20001
~~
0 01 1L R R Re e ® ®
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Examples of Possible Indirect Physics
- (e+e- ® f f )(direct)
ILC
Sensitivities to a Z’ Parameters of a WLWL Resonance
Imposing a1=1 (SM coupling) get
blue bar from LHC, red from ILC.
LHC fit,100fb-1
LC 1 TeV 1 ab-1
Miller61
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
The ITRP Recommendation• We recommend that the linear collider be based on superconducting r.f.
technology (from Exec. Summary)
– This recommendation is made with the understanding that we are recommending a technology, not a design. We expect the final design to be developed by a team drawn from the combined warmand cold linear collider communities, taking full advantage of the experience and expertise of both (from the Executive Summary).
– We submit the Executive Summary today to ILCSC & ICFA
– Details of the assessment will be presented in the ITRP report (to be published around mid September)
– The superconducting technology has features that tipped the balance in its favor. They follow in part from the low r.f. frequency.
Dorfan
62
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Beyond the TeV ILC• We need 2 LCs:
The TeV ILC, asap, then a multi- (~3?) TeV CLICThe CLIC two-beam accelerator concept The third CLIC test facility
Plan to demonstrate R1, R2 BY 2009: Δt ~ 5y relative to ILCYokoya
Miller
63
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Sparticles may not be very lightFull
Modelsamples
Detectable@ LHC
ProvideDark Matter
Dark MatterDetectableDirectly
Lightest visible sparticle →
← Second lightest visible sparticle
JE, Olive, Santoso, Spanos64
Nicola Coppola ICHEP04, HIGHLIGHTS 01.10. 2004
Summary of the Summary
• QCD ever more quantitative• Electroweak theory suggests new physics @ TeV scale:
Higgs + ?• Flavour physics becoming quantitative• CKM looking better and better• Neutrinos really do oscillate!• Growing symbiosis with cosmology• LHC on its way• Good ideas for future accelerators• ITRP has done its work
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