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Highlights from summer conferences. L. Bellagamba (INFN Bologna). Enorme quantita’ di risultati presentati piu’ di 300 articoli sottomessi a EPS e LeptonPhoton Per un report e’ ovviamente necessario fare una severa selezione. Overview. Non accelerator physics.
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Highlights from summer conferences
L. Bellagamba (INFN Bologna)
Enorme quantita’ di risultati presentati
piu’ di 300 articoli sottomessi a EPS e LeptonPhoton
Per un report e’ ovviamente necessario fare una severa selezione
Non accelerator physics
Gruppo I physics
WMAP: towards a highprecision Cosmology
studying the cosmic radiation background (CRB)
The Cosmologic Principle states that Universe is isotropic and homogenous at large scale
This was confirmed by the first CRB observations (Penzias e Wilson 1965)
At first sight CRB is isotropic
T=2.73 K
Looking to details:
 Disomogeneity1/1000
dipole due to Doppler effect
Where the CRB pattern come from ?
CRBpattern
snapshot of the
Universe at the
decoupling time
Compress the CMB map to study cosmology
5 degrees
Express sky as:
all the statistical information is contained in the angular power spectrum
compression
rarefaction…
baryons
Before (11 feb. 2003)
Primordial ripples
Fundamental mode
Geometry
Fit of the cosmological parameters
Using a flat Universe
(6 parameters)
Acceptable c2
Age of Universe:
13.4 0.3 Gyr
Age at decoupling:
372 14 Kyr
Baryon density:
0.047 0.006
Matter density:
0.29 0.07
Geometry of the Universe
Removing the flat condition in the model
Improvement precision respect to previous results (Boomerang)
Using also results from SN 1A and galactic clusters
strong constraints on WL and Wm
Riess et al. 2001
Extragalactic SN 1A
Verde et al 2002
Galactic clusters
We (and all of chemistry) are a small minority in the Universe
Now the question is:
What are Dark Matter and
Dark Energy?
Dark matter properties WIMPs
Dark matter natural candidate: LSP in Rp conserving SUSY
LSP in the MSSM is the lightest neutralino:
Higgsinos
Neutral gauginos
Direct detection in underground experiments
elastic scattering off a target nucleus:
 cross section depends on the relative velocity between WIMP and target
 the nuclear recoil energy is the measured quantity.
 Very low energy : ER 10 keV
 Very small interaction rate : down to 105 c/kg/day
Jun
Sun
~30 km/s
~220 km/s
Earth
Dec
Dark matter (II)
DAMAexperiments at Gran Sasso claims model independent evidence for WIMPS in the galactic halo
100 kg NaI(Tl) detector mass (scintillation)
Seeannual modulation signal (hearthorbital motion)
Effect 57%
Isotropic halo and dispersoin velocity
Allowed region for spin independent coupled WIMPS considering few different halo models and different values for the local WIMP velocity (170270 Km/s)
Latest results astroph/0307403
(7 annual cycles)
58000 + 49800 = 107800 Kg.days
Dark matter (III)
Other experiments:
DAMA new
UK/Boulby : NaIAD (NaI)xcheck for DAMA
UK/Boulby : ZEPLIN (Liq.Xe)
Stanford : CDMS (Ge e Si)
Frejus, France : EDELWEISS (Ge)
Remarks
Comparison between different exps. extremely difficult
Different targets can result in very different cross sections
Number of counts other expts. could expect on the basis of DAMA modulation results varies from few to zero.
Summary of the cosmological section
The precision CMB studies opens a new era for Cosmology
We are close to a Standard Cosmology able to fit a large number
of observations
Activity is going on:
 polarization study on WMAP data still going on
possible discrimination between different inflation models
 new satellite (Planck) will be launched in 2007
SUSY, offering a natural DM candidate, contributed to strengthen the link between highenergy physics and Cosmology.
The detection of WIMP/LSP in underground detector is an extremely difficult task at the limit of the present technology.
The techniques are anyway going better and better.
Can we discover first sparticle before LHC ?
DAMA already claimed to have it, but it is not a direct evidence and an independent check, also considering the difficult of the measurement, is certainly required.
K
c
b
c
W
s
New Physics in B Ks ?CP violation in the b sector:
dominated by a treelevel amplitude
Belle (2003) 140 fb1:
sin(2b) =0.733±0.057±0.028
:
sin(2b) =0.741±0.067±0.033
BaBar (2002) 81 fb1:
Belle 2003: sin2beff = 0.96 ±0.50
Belle result 3.5σ off respect to SM
BaBar 2003: sin2beff (φ KS) = +0.45±0.43±0.07
Closer to SM respect to previous results
Hint of new physics in B K ?
(NP effects might be large in loop induced processes)
2.1 s between BaBar and Belle:
more data absolutely needed to clarifythe situation
NEW: MW(Aleph) lower, small shifts
in heavy flavors, atomic PV close to SM
new Mt D0 Run I and CDF Run II
not included
Fit:
MH=96 GeV, MH<219 GeV at 95%CL
χ2/dof=25.4/15 4.5% prob
without NuTeV
MH=91 GeV, MH<202 GeV at 95%CL
χ2/dof=16.8/14 26.5% prob
OVERALL SM fine
except for NuTeV
NuTeV at FERMILAB measures NC/CC cross sections in n DIS

NuTeV main new feature is having both n and n beams
Independent measure of sin2q using n/nNC/CC cross sections exploiting the PASCHOSWOLFENSTEIN ratio
Most uncertainties and O(as) corrections cancel in the PW ratio
Corrections needed for:
non isoscalar target (2ZA), ne in the beam, higher twist, radiative corrections, effects of flavour asymmetries in the pdfs

NuTeV works at LO in QCD and finds
sin2qw(NuTeV)=0.2276±0.0013stat ±0.0006syst ±0.0006th
0.00003(Mt/GeV175)+0.00032 lnMH/100GeV
Global EW fit:
sin2qw= 0.2229 ±0.0004
~ 2.8 s
Dalla misura separata di Rn, Rn
NuTeV suggests a smaller lefthanded coupling
(III) NuTeV result O(1%) effect
possible SM explanations related to hadronic structure
Strange asymmetry
Isospin violation
A positive s reduces the anomaly
Naturally of O(1%), ds2W 0.002
Different models give this order of magnitude, ds2W<0
Sather,Rodionov et al,Londergan&Thomas
Discrepancy reduced ~ 30%
New MRST fit confirms such estimation but very large uncertainties
NuTeV finds much smaller effect
mH = 500 GeV
Recall:positive s reduces the NuTeV anomaly
 relies on inconsistent parameterization (total strangeness S 0)
 does not fit s in the context of global fit
 includes all available data
 accounts for strangeness conservation (S=0)
 fits s,sbar together with other pdfs
Negative s strongly disfavoured,
acceptable fits have 0.001< s <0.0031
Final remarks:
Fewissues still open: large sea uncertainties and shift from scould reduce discrepancy below 2σ
Given present understanding of hadron structure,
RPW is no good place for high precision physics
Problem: ~3σ discrepancybetween LR asymmetry of SLD and FB b asymmetry of LEP: in SM they measure the same quantity, sin2θeff
New AFB(b) preliminaries from OPAL and DELPHI
LEP: Zff
(e,m,t,c,b)
(t)
SLD: Z with beam pol.
The Chanowitz argument
2 possibilities, both involving new physics:
AFB(b) points to new physics
it’s a fluctuation or due to unknown syst.
But it is AFB(b) which pushes Higgs mass up !
without AFB(b) , the MH fit is very good
MH=42 GeV, MH<120 GeV at 95%CL
but in conflict with direct lower bound MH>114.4 GeV
In case, it ispossible to find NP that mimics a light Higgs.
For example SUSY can do thatwith light sleptons, tanβ>4
Altarelli et al
Conclusion is sensitive to top mass
improvement precision of Mtop is the priority Tevatron II
Excellent place for new physics unexplored loop effects ~ m2µ/Λ2
but needs chiral enhancement
Supersymmetry is natural candidate at moderate/large tanβ
No experimental news: BNL g2 experiment latest result from 2000 m+data
released 2002 :
soon result of 2001 mdata
expected 30% error reductions
Some theory developments:
4loop big, never checked!
had,LO
CMD2
Revised CMD2
LxL change
of sign
(g2)m news (II)
Incomplete compilation of theory predictions
EidelmanJegerlehner,
Davier et al,
Hagiwara et al
Largest theoretical uncertainties from
Vacuum polarization integrals involve vector spectral functions
which can be experimentally determined from two sources:
 e+e annihilation cross section (CMD2)
 Hadronic tau decays (ALEPH, CLEO, OPAL)
Tau data
e+e data
Final CMD2 π π data (2002) 0.6% syst error!
CMD2 have recently reanalyzed their data
Good agreement between Aleph, CLEO, Opal τ data
Davier at al (DEHZ)
aμhad,LO=709.0±5.1exp±1.2r.c±2.8SU(2)
Hagiwara et al (HMNT) NEW result:
aμhad,LO=691.7±5.8exp±2.0r.c.
~ 22.5σ
depending on which e+e analysis
Agreement with exp. results
ISR reduces the effective energy of the collision:even e+e colliders at fixed energy can investigaterange of s profit of large luminosities of meson
factories (DAFNE, CLEOC, BaBar, BELLE)
 interesting NEW results from KLOE (e+e ppin the region0.37 < sπ<0.93 GeV)
δaμ(had)=374.1±1.1stat±5.2syst±2.6th+(7.50.0)FSR
 to be compared with the NEW CMD2 (same s range)
δaμ(had)=378.6±2.6stat±2.2syst&th(it was 368.1)
Discrepancy with t data confirmed by KLOE
Further understanding needed
Possible violation of CVC or isospin symmetry?
e+
e
τ
ν
γ
W
π+
π
π0
π
CVC + isospin symmetry
Corrections by Cirigliano et al 02
SM works fine
Despite the severe tests performed in the attempt to discover some sign of new physics
no really convincing BSM signal so far
There are few points to clarify that will be further investigated in the next future
One of the next future priority is certainly improving the top mass precision.
A routine job for TEVATRON II but fundamental to better understand the few obscurities of the SM and eventually to discover the first convincing signs of new physics.
Non accelerator physics
Gruppo I physics
ZEUS Collab.,
PLB 559, 153 (2003)
Anomalous couplings between top, /Z and u/c may arise in SMextensions
H1 :5 candidates, 1.70.4 expected (Prelim.)
ktug
H1 Prelim., Contrib. Paper #181
ZEUS Collab., PLB 559, 153 (2003)
Final DELPHI results, Contrib. Paper #53
L3, PLB 549 (2002) 290
 No excess in H1 e p data
 No excess in ZEUS data in e & channels, candidates
 Agreement in the had. channel (but large bckgd)
 W prod full NLO corrections included
(recently available)
H1 Collab., PLB 561, 241 (2003)
ZEUS Prelim
e & m
had
130 pb1
H1 e+ p data, 105 pb1
e p l+ jet + PT,miss
Main SM contribution :
s(W)~1pb
The simplest best fit model has 6 parameters and
The probability to exceed is 5%
Can combine data with external surveys as well.
Flat LCDM still fits
Baryon density Wbh2 0.024 0.001
Matter density Wmh2 0.14 0.02
Hubble constant h0.72 0.05
Amplitude A 0.9 0.1
Optical Depth t0.166 + 0.076 – 0.071
Spectral index ns0.99 0.04
Fits not only the CMB but also a host of other cosmological observations.
Riess et al. 2001
Flat within errors
Improvement precision
respect to Boomerang
Using also results from SN
and galactic clusters
strong constraints on
WL and Wm
Verde et al 2002
Anticorrelation
Temperaturepolarization
Causal Seed model (Durrer et al. 2002)
Primordial Isocurvature i.c.
Preliminary studies
Data supports inflation
To some extent is possible to discriminate among different models
WMAP TE data in bins of Δl=10
Primordial Adiabatic i.c.
Beauty production at HERA
 Previously reported anomalies from HERA TEVATRON and LEP
 Larger statistics with HERA II data in the next future
btagging also will profit of the detectors upgrading in the vertex region
DIS
K
c
b
c
W
s
CPV news (I)
CP violation in SM due to a complex phase in CKM matrix
Bfactories allow precise measurements in bsector
and explore possiblebeyond SM sources of CPV
dominated by a treelevel amplitude
 2001 first signals for CPV outside of the kaon sector
Belle : sin(2b)=0.99±0.14±0.06
Babar : sin(2b) = 0.59±0.14±0.05
Updated results:
Belle (2003) 140 fb1:
h
sin(2b) =0.733±0.057±0.028
BaBar (2002) 81 fb1:
K (ek) and B (md,Vub , Vtd , sin (2)) sectors consistent with each other and SM
sin(2b) =0.741±0.067±0.033
Really going towards a precise measurement
r
claims model independent evidence for
WIMPS in the galactic halo
Dark matter (II)
100 kg NaI detector mass (scintillation)
 First results (2002) based on
58000 kgdays exposure (4 years)
Mc ~ 52 GeV
sp ~ 7x106 pb
See annual modulation signal (hearth orbital motion)
Search for New Physics in rare Bdecays
Theoretically cleanest example:
In the SM
sin(2b)eff = sin(2b) (Bf KS )
BaBar 2003: sin2beff (φ KS) = +0.45±0.43±0.07
Closer to SM respect to previous results
Belle 2003: sin2beff = 0.96 ±0.50
Belle result 3.5σ off respect to SM
Current WA: sin(2b)=0.731±0.056
But 2.1 s between BaBar and Belle:
more data absolutely needed to clarifythe situation
E158 (SLAC) new results for PV in Moller scattering
Huge luminosity
High polarization (~80%)
Results in agreement with SM
sin2qeff(Q2=0.027 GeV2)=
0.2371 0.0025 0.0027
Soon results from Run II
Last run (III) is going very well
Final results next year
H1 ( 115 pb1)
ZEUS ( 130 pb1)
selection
2e, M > 100 GeV
3 / 0.30 0.04
2 / 0.77 0.08
3e, M > 100 GeV
3 / 0.23 0.04
0 / 0.37 0.04
HERA multilepton eventsSearch for events with several leptons in final state
Mainly produced via collisions
H1, hepex/0307015, submitted to Eur. Phys. J
2e+3e
3e
M12(GeV)
observed / expected
(different angular ranges in H1 / ZEUS analyses)
+0.44
+0.46
0.43
0.43
Assuming CPT only LMA solution compatible with deficit observed by KamLAND
Best fit (thres. 2.6 MeV):
sin22q=1.0
Dm2=6.9 105 eV2
Solar neutrinos not a problem anymore:
LMA
106 cm2 s1
+1.01
FSSM=5.05
0.81
SMA
LOW
VAC
Predicted region at 95% CL from solar nu expts assuming LMA
MNSP matrix
Atmospheric, K2K
q23~450
Accelerator, reactor
q13 not measured yet
Solar, KamLAND
q12~300