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Electroweak Parameters and QCD Tests with Final State Searches: Summary of New Results

This paper presents results from various experiments conducted in 2004 and 2005, focusing on electroweak parameters and QCD tests with final state searches. Key findings include determinations of Mprop, sin2qw, and Mtop, contributions of charm and beauty to inclusive ep-scattering, proton beauty structure function measurements, and observations of large scaling violations. Furthermore, the study explores processes like beauty production, charm jets in DIS, and diffractive dijets, among others. The text summarizes HERA results, magnitudes of quarks in jets, and advancements in understanding diffraction phenomena. Various tests related to QCD factorization and deeply virtual Compton scattering are discussed alongside intriguing searches for exotic particles like the strange pentaquark. Data from HERA I and II runs, including isolated lepton events, multilepton events, and polarisation studies, are also presented. The paper highlights the ongoing physics investigations and outlines future research directions.

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Electroweak Parameters and QCD Tests with Final State Searches: Summary of New Results

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  1. Electroweak parameters F2cc and F2bb QCD tests with final states Searches Results with 2004/5 data Summary New Results from H1 2005’ event From Strbske Pleso to Madison: Olaf Behnke (Heidelberg) for the H1 collaboration

  2. Hera NC at high x Fit of el.weak parameters W aq, vq Ingredients for SM description: El. Weak par.: aq, vq, … p-PDFs Perform combined fit of el. weak par. and p-pdfs

  3. Fit of electroweak parameters: First HERA results on aq, vq Further results: • Mprop = 82.87 ± 1.83 GeV [exp] • sin2qw = 0.2151 ± 0.0040 [exp] • Mtop = 108 ± 44 GeV

  4. and New determination of Measure c and b contributions to the inclusive ep-scattering 3.75<Q2<60 GeV2 Exploit long b and c lifetimes Use track impact parameters meas. with the H1 vertex det. S=d/s(d)

  5. vs Q2 in bins of x Lumi ~ 57 pb-1 Precise new measurements In each Q2,x bin: >70% kin. acceptance!

  6. vs Q2 in bins of x These are the first measurements of the proton beauty structure function! Large scaling violations observed

  7. ~20% c and b contributions to the total x-secs ~0.2% ~30% ~1% ~20% ~4% b contribution strongly rising with Q2

  8. QCD tests with final states Jets: • asdetermination • Beauty production using events with muon and jets • Photoproduction of D* plus jet • Charm and beauty high pt photoproduction • D meson fragment. ratios and the charm fragmentation function • Charm jets in DIS • Jet shapes in tagged charm events • c and b using D* muon correlations Heavy flavours: • Diffractive dijets • Diffractive D* and CC • Elastic J/Psi production • Diffract. photoprod. of rho at large t • Dijet with a leading neutron • Deeply virtual compton scattering Diffraction:

  9. as from 3jets/2jets at high Q2 Dijets Jet Trijets as Jet Jet Average fitted as(mZ) Running as Average as(MZ) Consistent results

  10. Charm and Beauty in high pt dijet events (gp) Jet Q2 ~0 Use impact par. of tracks in jets Jet Excess Data/NLO in more forward direction Higher pT reached than for D* measurements

  11. Charm and Beauty in high pt dijet events (gp) Visible range: ptjet1(2)>11(8) GeV Measured quark fractions: fuds~58%, fc~35% , fb~7% Reach almost values expected for massless u,d,s,c,b ! ~1/11 ~4/11

  12. Beauty HERA summary plot: Data/NLO vs Q2 Many new data points since last year Main question (with long history): Excess data/NLO ?

  13. Diffraction: Diffractive parton densities H1 NLO analysis (2002) Quarks Incl. Diffr. Can we use these gluon and quark densities to predict other processes? QCD factorisation? Tevatron pp  fact. fails b b

  14. Diffractive dijets at HERA DIS: Q2>1 GeV2 Direct g Factorisation ok gp: Q2~0 Factorisation broken! Also res. g Xg Why suppression also for more direct g events ??

  15. Diffractive factorisation tests: CC, charm Charm: Factori-sation ok Charged Current: Data just become significant

  16. Deeply virtual compton scattering Access to skewed parton densities x-z x+z t First t slope measurement Fix norm. of pQCD models

  17. Searches: Lepton flav. violation , light Gravitinos

  18. D*p(3100) resonance New for DIS05: hep-ex03012 Acceptance corr. event yields 3.100 GeV Differential studies: Not confirmed (so far) by other experiments Compare to simple model (e.g. with isotropic decay)

  19. Strange Pentaquark (?) Search for q+(1530)K0s p Lumi=75 pb-1 No significant signal

  20. Strange Pentaquark (?) Search for q+(1530)K0s p 95% c.l. cross-section limits

  21. HERA II data e- data (2005) HERA II runs with polarised electron (positron) beams 2005 e-p: High lumi!  1 pb-1/day -25% H1 physics analysis: ~ 53 pb-1 e+p (2003-2004) ~ 21 pb-1 e-p (2005)

  22. Isolated lepton events with large ptmiss Excess Data/SM in HERA I data both for e and m Six new e events in HERA II data! e event from 2004 But: No m events (yet) in HERA II Need much more lumi to clarify!

  23. Total yield for HERA I and HERA II: Isolated lepton events with large ptmiss

  24. Multilepton events 1996-2004 e±p L=163 pb-1 (ICHEP04) New for DIS 2005: Analysis of 2005 e- data (21 pb-1): No new high mass events

  25. CC cross section as a function of polarisation Requires excellent control of calorimeter energy scales Neutral current analysis  used for calibration Charged current analysis El.magn. Hadronic

  26. CC cross section as a function of polarisation With brandnew data! Much effort invested e.g. for control of Lumi Polarisation dependence as expected from SM

  27. Summary • H1 physics highlights for DIS2005: • Electroweak parameters • F2cc and F2bb • as from 3/2 jets • Charged current with polarised electrons • Physics fun is continuing: Waiting for much higher luminosities!

  28. Polarisation dependence of the total charged current cross section (Andrei Nikiforov) Multi-lepton events and searches for the doubly charged Higgs (Andre Schoening) F2 and determination of the longitudinal proton structure function Fl at low Q2 (Alexey Petrukhin) F2 at low Q2 in QED compton scattering at HERA (Ewelina Lobodzinska) W boson mass and the light quark couplings to the Z boson (Benjamin Portheault) F2cc and F2bb at low and high Q2 using the H1 vertex detector (Tatsiana Klimkovich) Jet production at high Q2 (Thomas Kluge) Forward jets at low x in DIS (Albert Knutsson) Beauty production using events with muon and jets (Olaf Behnke) Photoproduction of D* plus jet (Gero Flucke) Charm and beauty high pt photoproduction (Lars Finke) D meson fragmentation ratios and the charm fragmentation function (Zuzana Rurikova) Charm jets in DIS (Adrian Perieanu) Jet shapes in Charm photoproduction (Maria Martisikova) Charm and beauty using D* muon correlations (Nick Malden) F2D and diffractive CC (Paul Laycock) Diffractive dijets (Matthias Mozer) Diffractive D* (Matthew Beckingham) Elastic J/Psi production (Christian Kiesling) Diffractive photoproduction of rho at large t (Carl Gwilliam Dijet cross sections for events with a leading neutron (Armen Bunatian) Deeply virtual compton scattering (Sasha Glazov) Prompt photons in photoproduction (Josef Ferencei) SUSY searches (Dave South) Searches for leptoquarks and lepton flavour violation (Linus Lindfeld) Isolated lepton searches (Christian Veelken) Analysis of the anti-charmed baryon state at H1 (Karin Daum) Search for a narrow baryonic resonance decaying to K0s p(pbar) (Christiane Risler) Summary of H1 results presented at DIS05

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