Summary of WG B contributions at DIS03 ElectroWeak and Physics Beyond the SM Convenor: Wilfried Buchmüller (DESY), Stefan Schlenstedt (DESY Zeuthen)  Electroweak Physics and Top Production (three+ talks)  Physics Beyond the Standard Model (18+ talks)  SUSY, LeptoQuarks, Contact Interactions, Extra Dimensions  Search for Excited Fermions  Excess of isolated leptons and search for unusual events  Limits on Single Top production

April 24, 2003DIS03 - WG B summary - S Schlenstedt2 ElectroWeak Physics over 1000 measurements can be presented as ~20 pseudo- observables (talks by A Mehta, G Altarelli and recent reviews) – on the Z pole: line shape, asymmetries, charm- and beauty-production – and: W mass and width, top-production, N-cross section (translated into sin 2  W or M W ), Atomic parity-violation … collected at LEP I/II, Tevatron and, HERA (see WG A)

April 24, 2003DIS03 - WG B summary - S Schlenstedt3 ElectroWeak physics at LEP II Talk by J Wilson Many precise measurements up to √s=209 GeV Branching ratio’s and cross sections new measurements of the W-mass at threshold and at high energies and the W-width the triple charged and neutral gauge couplings (ZWW, ZZZ, ZZ  …)

April 24, 2003DIS03 - WG B summary - S Schlenstedt4 ElectroWeak physics at LEP II cont’d Talk by J Wilson threshold measurement Measure directly the triple-boson vertex

April 24, 2003DIS03 - WG B summary - S Schlenstedt5 ElectroWeak physics at LEP II Talk by J Wilson … and lepton universality and  the global SM fit

April 24, ElectroWeak results from Tevatron Run I Talk by A Stone W Top cross section (pb) (based on 100 evts) Z  (  2 ) Theory

7 Tevatron Run II  Higher beam energy  new detectors and trigger  CDF and D0 took ~100 pb -1, presented analyses of 30…90 pb -1  detector commissioning and physics analysis hand in hand  in 0304 less integrated luminosity but improved detector acceptances Talks by A Stone and T Nelson

April 24, 2003DIS03 - WG B summary - S Schlenstedt8 ElectroWeak Results from CDF Talk by T Nelson  W  B ( W  l ) = 2640 ± 12 ± 93 ± 158 lum pb  Z  B ( Z  ll ) = ± 4.3 ± 10.6 ± 15.1 lum pb Run II  tt (pb) measured  W   B(W  e,  ),  Z  combined e, , 

9 D0 EW Results  Combining the observation of the top decay channels an excess of 3s is observed, compatible with a signal expectation at the 35% CL  Four new W & Z cross section measurements: Talk by A Stone   (W) B(W  ) 3226±128±100±323 lum pb  (W) B(W  e ) 3054±100± 86±305 lum pb  (Z) B(Z  ) 264± 7± 17± 26 lum pb  (Z) B(Z  ee) 294± 11± 8± 29 lum pb  tt (pb) 0 40

10 Because of two 3 sigma anomalies, the Standard Model (SM) fit of the precision electroweak data has a poor confidence level, CL= […] The data then favor new physics whether the anomalous measurements are excluded from the fit or not…and the Higgs boson mass cannot be predicted until the new physics is understood. M Chanowitz, hep Higgs mass constraints ElectroWeak summary A FB (b) and NuTeV ~3  effects: Just a regular statistical pattern? QCD effects (s, c, isospin…)?

April 24, 2003DIS03 - WG B summary - S Schlenstedt11 NNLO for EW, Higgs and SUSY processes  Calculation of cross sections in pQCD: factorization of calculable “hard” short-distance and “soft” long- distance physics, the latter with virtual corrections  A unified approach and a master formula to calculate in NNLO the soft and virtual functions for processes like hadron-hadron- (Drell-Yan), lepton-hadron- scattering, total xsec’s, SM and charged Higgs production, FCNC single top production, SUSY …  Example FCNC single top production at HERA: eu  et Talk by N Kidonakis at √s = 300

April 24, 2003DIS03 - WG B summary - S Schlenstedt12 Phenomenology of a SU(2) Triplet Higgs  Extension of the SM Higgs sector: add a real triplet to the complex doublet (unlike the MSSM with a second doublet)  investigate if the then “SM” Higgs can be heavy and what the relation to the new Higgs masses is Talk by A Sabio-Vera checked if the Quantum- corrections are changing the picture (  no)

13 April 24, 2003DIS03 - WG B summary - S Schlenstedt Double charged Higgs at LEP Predicted by LR super symmetric model (Higgs triplet): Decay in two charged leptons, mainly in tau’s. Yukawa coupling to lepton is free parameter. h  >10 -7 : look for 4  ’s close to interaction point h  <10 -7 : search for kick of charged tracks h  <10 -8 : search for anomalous ionisation OPAL: m H >98.5 GeV/c 2 Talk by A Tilquin

April 24, 2003DIS03 - WG B summary - S Schlenstedt14 Doubly Charged Higgs at CDF “Any model with Higgs triplets predicts double charged Higgs.” Reach sensitivity up to 125 GeV/ c 2 by Summer Talk by A Munar Same sign dielectron data analyzed Same sign dielectron data analyzed Selection: High E T inclusive electron trigger Selection: High E T inclusive electron trigger Search in mass windows of 10% M H (3  ) Search in mass windows of 10% M H (3  ) Signal: 0 observed Control Region Z mass 0 observed ( predicted) (see also H ++ from H1 later)

15 April 24, 2003DIS03 - WG B summary - S Schlenstedt Slepton searches at LEP e+e+ e-e- ,Z * e+e+ e-e- 2 acoplanar leptons + missing energy Main background from WW  l l Channel  1 0 massMass limit Selectron 0 GeV 40 GeV 99.6 GeV 99.4 GeV Smuon 0 GeV 40 GeV 94.9 GeV 96.5 GeV stau 0 GeV 40 GeV 85.0 GeV 91.7 GeV Talk by A Tilquin

16 April 24, 2003DIS03 - WG B summary - S Schlenstedt Search for Neutralino at LEP Chargino, neutralino slepton and Higgs results are combined. LSP mass limit obtained at high tan(  ) Talk by A Tilquin

April 24, 2003Talk by E Perez17 Search for resonant squarks in H1 Here: e + p data, L = 63 pb -1 Here: e + p data, L = 63 pb -1 High E T e + jet i.e. look for signal in high E T / Q 2 NC DIS (mainly at large ’ ) 1. Rp-violating decay : q  e q 2. “Gauge” decays : q  q  i 0 or q  i + or q g followed by cascade decay of gaugino e+ + multi-jets ………………… NC DIS e- + multi-jets …………………  bckgd free + multi-jets …………………… CC DIS e ( ) + l + multi-jets…………… small SM bckgd (similar to scalar LeptoQuark ) e+e+ d e+e+ d u L j ~ ’ 1j1 q e+e+ d u 0101 u L j ~ ’ 1j1 q* ~ e +, e -, q (Majorana)  L = 2 ~ All decays involving at most 2 gauginos are considered Large number of final states ! BRs depend on model parameters Look for the signal in ~ all possible decay modes: [ data: H1, EPJC20 (2001) 639. ] ~ ~

April 24, 2003DIS03 - WG B summary - S Schlenstedt18 Constraints in the MSSM sector from H1 Scan of the SUSY parameter space: M 2, , tan  Limits on ’ 1j1 do not depend strongly on the MSSM parameters For ’ = 0.3 ( ’ 2 / 4  =  em ) : squarks can be ruled out up to  280 GeV For ’ = 0.3 ( ’ 2 / 4  =  em ) : squarks can be ruled out up to  280 GeV HERA’s sensitivity extends beyond the indirect limits from low energy experiments for c L (also for t L ) ~~ Masses of gauginos & couplings to f-f  branchings ~ Consider first an “unconstrained model” : sfermion & gaugino sectors are not related, i.e. M f are free parameters ~ 0.3 weakest strongest M squark (GeV) ’ 1j c L (APV ) ~ u L (  0 ) ~ example for j=1,2 Talk by E Perez

19 m 0 (GeV) 1500 m 1/2 (GeV) Constraints on mSUGRA model : ’ 111,121 from H1 Sfermion & gaugino masses related via RGE m 0 (m 1/2 ) = common mass param for scalar (gauginos) at GUT scale Assume Radiative Electroweak Symmetry Breaking 5 parameters : m 0 (GeV) m 1/2 (GeV) L3 D0 (Run I) For medium tan  : H1’s sensitivity extends beyond the domain excluded by D0  Complementarity. However H1 bounds depend on ’, D0’s do not. D0 (Run I) (pair prod q & g) ~~ (pair prod, sfermion &  ) In such constrained models : LEPII has highest sensitivity ’ 1j1 = 0.3 tan  = 2 ’ 1j1 = 0.3 tan  = 6 larger BR (  0 1  qq) m 0, m 1/2, tan , sgn(  ), A 0 Talk by E Perez Talk by H Dreiner

20 April 24, 2003DIS03 - WG B summary - S Schlenstedt Constraints on mSUGRA : ’ 131 from H1 ’ 131 would allow resonant stop production at HERA. Interesting since the stop might be the lightest squark ! light … ~  0 1 < 30 GeV, i.e. “loose” t  b  + 1  b  0 1 XX  + 1 < 30 GeV, “loose” t  b  + 1 sensitivity via RpV decay only m 0 (GeV) m 1/2 (GeV) ’ 131 = 0.3 Larger part of the parameter space is covered (compared to the case ’ 1j1, j  3) Sensitivity to M(t 1,L ) up to  270 GeV Sensitivity to M(t 1,L ) up to  270 GeV NB: Tevatron RunI : different frameworks, but typical sensitivities  130 GeV. RunII:  GeV For intermediate m 0, excluded domain not ruled out by LEPII Discovery potential for RpV stop at HERA with larger L ! Discovery potential for RpV stop at HERA with larger L ! ~ the stop tan  = 10 Talk by E Perez

April 24, 2003DIS03 - WG B summary - S Schlenstedt21 Resonance search in the CDF-dijet Spectrum Event Selection: Event Selection: Inclusive Jet Sample (75 pb -1 ), two Highest E T jets Fit the Mass Spectrum with a smooth background No evidence of resonances Limits on Axigluons, Excited Quarks, Octet Technirhos, E6 Diquarks, W’  already improved with respect run I Talk by A Munar

April 24, 2003DIS03 - WG B summary - S Schlenstedt22 LeptoQuarks at Tevatron and qq  LQ LQ LQ decay and search strategy: LQ  e ( )q,  q with   Branching Ratio (LQ  l q) (242) DZero (242) CDF Vector Yang-Mills Coupling (GeV/c) Vector Minimal Coupling (GeV/c) Scalar (GeV/c)  1 st Gen. already strong limits from run I for all three generations LQ’s appear in extended gauge sectors and composite models, scalar and vector particles, coupling to u or d

April 24, 2003DIS03 - WG B summary - S Schlenstedt23 LeptoQuarks at D0 Talks by O Kouznetsov 1st Gen LQ : 2 e + 2 jets M LQ > 179 GeV M LQ > 225 GeV ( L = 115 pb -1 ) Theoretical NLO  (for Q = 1, 0.5, 2  M LQ )  limit at 95% CL L = 43.0 pb -1 2nd Gen 2  + 2 jets L = 30.0 pb -1 M LQ > 157 GeV M LQ > 200 GeV ( L = 120 pb -1 ) Run I

April 24, 2003DIS03 - WG B summary - S Schlenstedt24 LeptoQuarks at CDF (1rst Gen) Talk by A Munar 2 high E T electrons and 2 jets Missing Energy and 2 jets M(LQ) > 230 GeV/c 95% CL (Run I 220 GeV/c 2 ) Limit already better than Run I 25% increase in the cross section ~factor 1/3 less luminosity acceptances slightly higher M(LQ) < 60 GeV/c 2 or M(LQ) > 107 GeV/c 95% CL ( not searched in Run I by CDF) Limit from D0 (Run I, similar luminosity) M(LQ) > 98 GeV/c 95 % CL

April 24, LeptoQuarks at H1 Talk by J Scheins direct search of resonant LQ production in NC mass spectrum : no excess  limits e - sensitive to F=3B+L= data above √s=318 u- and s-channel contribution

April 24, 2003DIS03 - WG B summary - S Schlenstedt26 LeptoQuarks at ZEUS Talk by G Barbagli Combine channels with eq and q when possible Constant for scalar LQ as function of branching ratios  into eq and q

27 April 24, 2003DIS03 - WG B summary - S Schlenstedt LeptoQuarks at LEP New color triplets bosonic fields mediating interaction between quark and leptons SpinQF ll Scalar Vector  1/3,  2/3  4/3,  5/3 0,20,1/2,1 e+e+ e-e- ,Z LQ e+e+ e-e- OPAL OPAL Preliminary I3I3 Talk by A Tilquin

April 24, Contact Interaction at HERA parametrize the deviation from SM through four- fermion contact interaction with an effective coupling g 2 /  2 for different chiral combinations Talks by J Scheins and G Barbagli Limits for effectice mass scale  eeqq 1.7 … 7.0 TeV All models are consistent with the SM

29 April 24, 2003DIS03 - WG B summary - S Schlenstedt Extra dimensions at LEP Trying to solve the hierarchy problem: Weakness of Gravity at electroweak scale Our word confined to four dimensions Gravity propagates in extra dimensions (ADD) Planck mass Radius of extra dimensions Number of ED Planck mass in ED By choosing M D  EW  No hierarchy problem d=1  R=10 13 mExcluded d=2  R=1 mm d=3  R=1 nm …. d=7  R=1 fmMax in M-theory f,V G 1/M Pl Small but large number of states (G KK ) Talk by A Tilquin

30 April 24, 2003DIS03 - WG B summary - S Schlenstedt Extra dimensions at LEP (cont) Direct search: missing energy Indirect: look for deviation from (d  /d  ) SM For n=2 M D >1.36 TeV LEP average: M S >1.2 TeV ( =+1) M S >1.09TeV ( =-1) Talk by A Tilquin

April 24, 2003DIS03 - WG B summary - S Schlenstedt31 Search for Extra Dimensions at D0 where Fit the distributions in the M ll - cos  * plane to determine the value of  G di-e:  G = 0.0  0.27 TeV -4, di-  :  G = 0.02  1.35 TeV -4 (  G = 0 in SM) Extract 95% CL upper limits on  G  translate to 95% CL lower limits on Planck scale M S Talk by O Kouznetsov Di-e limit close to Run I, Di-  (new )

April 24, 2003DIS03 - WG B summary - S Schlenstedt32 Search for Extra Dimensions at HERA Search again for deviations in the Q 2 distribution Talks by J Scheins and G Barbagli M S > (TeV)H1ZEUS = =

April 24, 2003DIS03 - WG B summary - S Schlenstedt33 Talk by M Schneider Excited Fermions : Composite models to explain the number of families

April 24, 2003DIS03 - WG B summary - S Schlenstedt34 Excited Fermions at HERA Talk by M Schneider Quarks  Electron  > HERA superior at high s (LEP) > more sensitive at small f s (FNAL) Neutrino 

35 April 24, 2003DIS03 - WG B summary - S Schlenstedt Excited fermions at LEP In composite models, fermion & boson are composite with and associated energy scale . Lot of decay channel at LEP: ,Z,W,g f/   e+e+ e-e- e*e*  From differential x-section gauge group weights factor Talk by A Tilquin

April 24, 2003DIS03 - WG B summary - S Schlenstedt36 Excited Fermions at CDF Talk by A Munar Search 0 events observed Limits on M e  and  BR(e *  e  ) - M e  = , M e  < 785 GeV/c 2 compare to current Limit ( H1 ) M e  =  M e  < 223 GeV/c 2 M e  =  M e  < 223 GeV/c 2

April 24, 2003DIS03 - WG B summary - S Schlenstedt37 Inclusive Searches in DiPhoton Signature at CDF Search for Diphoton + extra leptons: 0 events found (in agreement w SM)  Limits on Gauge Mediated Supersymmetry Observed: 2 Expected Events: 2  2 M C > 113 GeV/c 95% C.L. Talk by A Munar

April 24, 2003DIS03 - WG B summary - S Schlenstedt38 Unusual events at HERA

April 24, Isolated e and  at HERA with large missing p T Confirmation of excess H1 in e + data no excess in H1 e – and ZEUS e ± “Backgrounds” well understood largest SM contribution W production (hadronic channel checked as well ) Excess at large p T and M T where the SM contribution is small Talk by G Frising W production calculated in NLO (two independent calculations) correction ± 10-15% w reduced scale uncertainty - not the source of the H1 excess Talk by C Schwanenberger

April 24, 2003DIS03 - WG B summary - S Schlenstedt40 Unusual events at HERA

April 24, 2003DIS03 - WG B summary - S Schlenstedt41 Isolated  at ZEUS with large missing p T Talk by D Lelas

April 24, 2003DIS03 - WG B summary - S Schlenstedt42 Multileptons at HERA Talk by A Parenti di-  cross section (H1) and events (ZEUS): OK di-e cross section (H1) and events (ZEUS): OK H1 observes excess at high masses M 12 >100: 3/3 (for 2/3 e) and expects.25/.23 ZEUS observes 2/0 (for 2/3 e) and expects 1.2/0.4 Search for Higgs ++ (coupling to di-lepton) as source for excess  too small  set limits at high p T mainly  exclusion plot on coupling h ee Understand this SM process, e.g. as BG to isolated leptons and for the

April 24, 2003DIS03 - WG B summary - S Schlenstedt43 Single Top production at HERA  physics explanation of the lepton excess could be anomalous top production in FCNC (see Fritsch and Holtmann 1999) - the SM cross section is small ~1 pb 1. Search for isolated electron or muon with a high missing p T (from the ) 2. Search for 3 jets (two from W)  reconstruct the “top” mass  main Background is SM W production  no excess found: set 95% CL limit on  (ep  etX) and the tu  magnetic coupling limit   u,c t W b W  lep or had p ee  H1ZEUS  (pb) < 0.43 pb0.23 pb  < < Talks by A Schöning and D Dannheim (status of ICHEP02) 

April 24, 2003DIS03 - WG B summary - S Schlenstedt44 Talk by D Dannheim

April 24, 2003DIS03 - WG B summary - S Schlenstedt45 Anomalous t-coupling and SUSY at LEP Talk by A Tilquin R-parity violation l,q W,q e+e+ e-e- t b

April 24, 2003DIS03 - WG B summary - S Schlenstedt46 Summary  LEP1/2 and Tevatron run I and HERA I data sets analyzed  Tevatron run II preliminary results, HERA II will start  Electroweak Standard Model sector well measured and understood: we need more top and of course the Higgs  One expects Physics Beyond the SM at  (1/  G F ) ≈ 300 GeV  A wide search program showed no signal yet  A few interesting event classes need confirmation at high luminosities at FNAL and DESY Many thanks to the speakers and the local help