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Enorme quantita’ di risultati presentati piu’ di 300 articoli sottomessi a EPS e Lepton-Photon

Highlights from summer conferences. L. Bellagamba (INFN Bologna). Enorme quantita’ di risultati presentati piu’ di 300 articoli sottomessi a EPS e Lepton-Photon Per un report e’ ovviamente necessario fare una severa selezione. Overview. Non accelerator physics.

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Enorme quantita’ di risultati presentati piu’ di 300 articoli sottomessi a EPS e Lepton-Photon

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  1. Highlights from summer conferences L. Bellagamba (INFN Bologna) Enorme quantita’ di risultati presentati piu’ di 300 articoli sottomessi a EPS e Lepton-Photon Per un report e’ ovviamente necessario fare una severa selezione

  2. Overview Non accelerator physics • WMAP: towards a high-precision cosmology • Dark matter: DAMA result • News from CP violation in the b-sector • EW tests: possible disagreements with SM expectations • - NuTeV result • - sin2qW from forward-backward/left-right asymmetries • (g-2)m Gruppo I physics

  3. Recent results from WMAP WMAP: towards a high-precision 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 • Disomogeneity1/100000 • (COBE beginning ‘90) • Important discovery: first observations of CRB anysotropies

  4. Where the CRB pattern come from ? • Gravity fluctuations acts on baryon-photon gas • oscillation (compression – rarefaction) due to gravity and pressure of the plasma • At the decoupling time the photons are released (the Universe become trasparent) CRBpattern snapshot of the Universe at the decoupling time

  5. Compress the CMB map to study cosmology 5 degrees Express sky as: all the statistical information is contained in the angular power spectrum

  6. WMAP 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

  7. Flat within errors 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

  8. We (and all of chemistry) are a small minority in the Universe Now the question is: What are Dark Matter and Dark Energy?

  9. Dark matter (I) 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 10-5 c/kg/day

  10. 60 ° 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  5-7% 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 (170-270 Km/s) Latest results astro-ph/0307403 (7 annual cycles) 58000 + 49800 = 107800 Kg.days

  11. NaIAD 2002 (new 25 kg.yrs) Dark matter (III) Other experiments: DAMA new UK/Boulby : NaIAD (NaI)x-check 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.

  12. 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 high-energy 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.

  13. J/ K c b c W s New Physics in B   Ks ? CP violation in the b sector: • B  J/ Ks dominated by a tree-level amplitude Belle (2003) 140 fb-1: sin(2b) =0.733±0.057±0.028 : sin(2b) =0.741±0.067±0.033 BaBar (2002) 81 fb-1: 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

  14. Global EW fit 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

  15. The NuTeV result (I) 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 PASCHOS-WOLFENSTEIN ratio Most uncertainties and O(as) corrections cancel in the PW ratio Corrections needed for: non isoscalar target (2ZA), ne in the beam, higher twist, radiative corrections, effects of flavour asymmetries in the pdfs -

  16. The NuTeV result (II) NuTeV works at LO in QCD and finds sin2qw(NuTeV)=0.2276±0.0013stat ±0.0006syst ±0.0006th -0.00003(Mt/GeV-175)+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 left-handed coupling

  17. (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

  18. NuTeV (IV) Strange Asymmetry Recall:positive s- reduces the NuTeV anomaly • NuTeV: Dimuons (charm production) • s-=-0.0027±0.0013(low x) BUT NuTeV fit to s- - relies on inconsistent parameterization (total strangeness S 0) - does not fit s- in the context of global fit • New CTEQ 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 s-could reduce discrepancy below 2σ Given present understanding of hadron structure, RPW is no good place for high precision physics

  19. Asymmetries at the Z pole (I) 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: Zff (e,m,t,c,b) (t) SLD: Z with beam pol.

  20. Asymmetries (II) 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

  21. (g-2)m news (I) 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 g-2 experiment latest result from 2000 m+data released 2002 : soon result of 2001 m-data expected 30% error reductions Some theory developments: 4loop big, never checked!

  22. am had,LO CMD-2 Revised CMD-2 LxL change of sign (g-2)m news (II) Incomplete compilation of theory predictions Eidelman-Jegerlehner, 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 (CMD-2) - Hadronic tau decays (ALEPH, CLEO, OPAL) Tau data e+e- data Final CMD-2 π π data (2002) 0.6% syst error! CMD-2 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. ~ 2-2.5σ depending on which e+e- analysis Agreement with exp. results

  23. (g-2)m news (III) 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, CLEO-C, 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+(7.5-0.0)FSR - to be compared with the NEW CMD-2 (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? • KLOE is soon expected to improve the precision • BaBar is finalising similar analysis • Maybe new inputs will come from BELLE e+ e- τ- ν γ W π+ π- π0 π- CVC + isospin symmetry Corrections by Cirigliano et al 02

  24. SM status summary 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.

  25. Overview Non accelerator physics • WMAP: towards a high-precision cosmology • Dark matter: DAMA result • News on solar n oscillations • News from CP violation in the b-sector • EW tests: possible disagreements with SM expectations • - NuTeV result • - sin2qW from forward-backward/left-right asymmetries • (g-2)m • Single top production: example of complementarity between different colliders Gruppo I physics

  26. FCNC couplings involving the top quark ? ZEUS Collab., PLB 559, 153 (2003) Anomalous couplings between top, /Z and u/c may arise in SMextensions • single top production @ LEP & HERA • t  u/c + /Z @ Tevatron H1 :5 candidates, 1.70.4 expected (Prelim.) • not excluded by LEP & Run I data • ZEUS vs H1 : too few events so far… •  looking forward to doubling L ! • Sensitivity @Tevatron : • mainly via radiative top decays • u/c  t :  quite large but huge bckgd ! ktug H1 Prelim., Contrib. Paper #181 ZEUS Collab., PLB 559, 153 (2003) Final DELPHI results, Contrib. Paper #53 L3, PLB 549 (2002) 290

  27. HERA events with isolated lepton + PT,miss (I) e p   + jet + X e p   + jet + X jet e p 

  28. HERA events with isolatedlepton+ PT,miss(II) - 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 pb-1 H1 e+ p data, 105 pb-1 e p  l+ jet + PT,miss Main SM contribution : s(W)~1pb

  29. Descrizione del fit 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.

  30. Geometry 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 Anti-correlation Temperature-polarization 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.

  31. Phot. Beauty production at HERA - Previously reported anomalies from HERA TEVATRON and LEP • btagged exploiting semileptonic • decay b  cm • Unfold from charm, uds using • d(Si) and Ptrel (m-jet) • Compare with NLO QCD directly in measured range • ZEUS results in quite good agreement with SM predictions • H1 photoproduction a bit above - Larger statistics with HERA II data in the next future b-tagging also will profit of the detectors upgrading in the vertex region DIS

  32. J/ K c b c W s CPV news (I) CP violation in SM due to a complex phase in CKM matrix B-factories allow precise measurements in b-sector and explore possiblebeyond SM sources of CPV • B  J/ Ks dominated by a tree-level 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 fb-1: h sin(2b) =0.733±0.057±0.028 BaBar (2002) 81 fb-1: 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

  33. DAMAexperiments at Gran Sasso 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 kg-days exposure (4 years) Mc ~ 52 GeV sp ~ 7x10-6 pb See annual modulation signal (hearth orbital motion) • Latest results astro-ph/0307403 • (3 more annual cycles) • 58000 + 49800 = 107800 Kg-days

  34. CPV news (II) Search for New Physics in rare B-decays Theoretically cleanest example: In the SM sin(2b)eff = sin(2b) (Bf 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

  35. E158 (SLAC) new results for PV in Moller scattering Huge luminosity High polarization (~80%) • suppressed at tree level • sensitive to sin2q • sensitive to new physics • complementary to collider exps. 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

  36. expt H1 ( 115 pb-1) ZEUS ( 130 pb-1) 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 events Search for events with several leptons in final state Mainly produced via  collisions H1, hep-ex/0307015, submitted to Eur. Phys. J 2e+3e 3e M12(GeV) observed / expected (different angular ranges in H1 / ZEUS analyses)

  37. Solar nnews +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 10-5 eV2 Solar neutrinos not a problem anymore: LMA • SNO, (April 2002) 106 cm-2 s-1 +1.01 FSSM=5.05 -0.81 SMA • FSNO=5.09 • KamLAND (December 2002) • observed evidence for reactor neutrino disappearence at ~ 180 Km distance LOW VAC Predicted region at 95% CL from solar nu expts assuming LMA

  38. Summary onn MNSP matrix Atmospheric, K2K q23~450 Accelerator, reactor q13 not measured yet Solar, KamLAND q12~300 • n physics is certainly the sector with the most impressive developments in the last few years. • In this sector we discovered the only BSM physics so far, even if a natural extension of the SM can accommodate n masses and mixing. • the old solar n problem, which tormented us since 60’, has been finally understood • In the next few years accelerator and reactor experiments will give insight on the still unmeasured mixing angle and, hopefully, the first “appearance” signal will give us the direct evidence that n do oscillate.

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