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Resolving the Inner Structure of Matter The H1 Experiment at HERA

Resolving the Inner Structure of Matter The H1 Experiment at HERA. Max Klein (University of Liverpool). Talk at Plovdiv - Bulgaria. History HERA H1 and its physics Completing H1 Outlook. positively charged massive atomic nucleus. Discovery of the atomic nucleus 1909. atom.

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Resolving the Inner Structure of Matter The H1 Experiment at HERA

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  1. Resolving the Inner Structure of Matter The H1 Experiment at HERA Max Klein (University of Liverpool) M. Klein H1 27. 3. 2007 Talk at Plovdiv - Bulgaria

  2. History HERA H1 and its physics Completing H1 Outlook M. Klein H1 27. 3. 2007

  3. positively charged massive atomic nucleus Discovery of the atomic nucleus 1909 • atom • Ernest Rutherford (1871-1937) • H. Geiger und E. Marsden M. Klein H1 27. 3. 2007

  4. QED • photon exchange • - incalculabe formfactors (charge, magn. moment) e e p p Elastic electron scattering ep -> ep • Feynman diagrams 1949 Momentum transferred to p elastic scattering off a proton with charge distribution M. Klein H1 27. 3. 2007

  5. Scattering cross section MottKurve experimentalcurve Scattering angle Protons have finite size • 1955 R.Hofstadter and R.McAllister • elastic ep scattering • experimental curve (-) above the theoretical prediction of Mott (-) • Mott 1929: • electron-scattering of • pointlike particles • formfactor M. Klein H1 27. 3. 2007

  6. SLAC Deep Inelastic Scattering ep -> eX (1969) • resolution pointlike scattering centers inside the proton • Friedman, Kendall, Taylor M. Klein H1 27. 3. 2007

  7. Deep Inelastic Electron-Proton Scattering M. Klein H1 27. 3. 2007

  8. HERA: quarks are pointlike down to proton radius/1000 Inclusive cross section ep -> eX exhibits so far no extra formfactor -> Limits on SUSY, leptoquarks, extra dimensions, quark radius… Luminosity upgrade to probe deeper the smallest dimensions nucleon formfactor present limits ? ZEUS r < 0.85 H1 r < 1.0 10-18m finite quark size M. Klein H1 27. 3. 2007

  9. HERA Hoch-Energie Ring Anlage - High Energy Ring Accelerator M. Klein H1 27. 3. 2007

  10. Nature Vol 400 1 July 1999 M. Klein H1 27. 3. 2007

  11. HERA: built 1985-1991 6.2 km ring accelerator(s) Superconducting p ring Warm magnet e ring Data delivery since 1992 M. Klein H1 27. 3. 2007

  12. M. Klein H1 27. 3. 2007

  13. ZEUS H1 • protons 920 GeV • electrons 27.6 GeV M. Klein H1 27. 3. 2007

  14. g/Z0 Q2 HERA - Deep inelastic scattering and searches at the energy frontier High Q2-> Low x -> M. Klein H1 27. 3. 2007

  15. x 0 1 x 0 1 1/3 x 0 1 1/3 The function characterising the proton’s structure no substructure u 3 free valence quarks u d 3 bound quarks Gluon Valence quarks Sea quarks gluons M. Klein H1 27. 3. 2007

  16. Expectations on the density of partons before HERA M. Klein H1 27. 3. 2007

  17. HERA discovered high density state of matter (QCD, neutrino astrophysics, ..) 1992 data ~30nb-1 1997 data ~30pb-1 F. Wilczek M. Klein H1 27. 3. 2007

  18. H1 and its physics M. Klein H1 27. 3. 2007

  19. ~320 authors, 40 institutes 100 PhD students, 50 engineers M. Klein H1 27. 3. 2007

  20. Fast Track Trigger Forward Proton and Neutron Spectro- meters Luminosity spectrometer p e 27.5 GeV 920 GeV Forward tracking: Si + DC M. Klein H1 27. 3. 2007

  21. Physics at HERA (the expected and theunexpected) • Inclusive ep measurements (NC, CC-inverse neutrino i.a.) -> pdf’s, gluon, • Low x physics: small coupling and high density of partons -> “CGC, BFKL..” • Heavy flavour physics (c and b: production and fragmentation dynamics) • Final state physics (parton emission,,jets, y structure, dijet correlations ) • Diffraction [all related: e.g. “the structure of charm jets in diffraction”] • Parton amplitudes (DVCS) • Searches for exotic states (pentaquarks) and less? exotic ones (instantons) • Searches: substructure, leptoquarks, SUSY, isolated lepton events • Electroweak physics (spacelike region) • classic DIS • QCD • Searches • elweak for HERA physics see also: • Talks at DIS05, April 2005, Madison • 4/06, Tsukuba and 4/07, Munich M. Klein H1 27. 3. 2007

  22. Q2/GeV2 M. Klein H1 27. 3. 2007

  23. Asymptotic Freedom RGE gluon & quark loops Prediction confirmed in many reactions Nobel price 2004 ( Gross, Politzer, Wilczek) At small distances < fm quarks are free QPM restored in the limit of perturbative QCD At large distances, quarks are confined.(?) Lattice, string theories, nonperturbative regime There is a 3rd region discovered at HERA, where the coupling is small BUT the densities are large (low x physics, AA, superhigh energy neutrino physics, forward physics at the LHC) leading and next-to-leading order (NLO) M. Klein H1 27. 3. 2007

  24. The first ever measurement of the beauty contents of the proton F2b [lifetime tag] Small fraction of cross section. [Beauty in pt(rel) and  still above NLO QCD]. 57 pb-1 Central Silicon Tracker (CST/H1) M. Klein H1 27. 3. 2007

  25. High energy allows to take snapshots of proton structure: photon fluctuates into colour dipol. Its virtuality allows to scan through p’s structure. HERA measured the transition from hadronic (soft) to partonic (hard) behaviour which occurs at 0.3fm --> new data to come hc/Q = 6.3 2.0 0.6 0.2 0.06 0.02 fm F2 x- at small x rise of the parton densities M. Klein H1 27. 3. 2007

  26. The end of HERA operation at high energies (1992-2007) 27.6 GeV * 920 GeV --> 460 GeV 4-6/2007 M. Klein H1 27. 3. 2007

  27. M. Klein H1 27. 3. 2007

  28. Polarisation asymmetries establish parity violation ~vqae at small distances M. Klein H1 27. 3. 2007

  29. Completing H1’s Physics Programme 2007-2010+ Take low proton beam energy data (until 2.7.2007) Use all data available for final measurements Analyses in high order QCD (NNLO in inclusive case) Combination with ZEUS data where appropriate Highest possible accuracy in testing QCD and predictions for LHC M. Klein H1 27. 3. 2007

  30. Two independent structure functions characterise inclusive DIS completely F2 : quarks FL : gluons Measurement of FL just starting at HERA M. Klein H1 27. 3. 2007

  31. deep inelastic neutral current scattering event in the H1 apparatus yp Spacal p e‘ e 27.5 GeV 920 GeV Silicon Strips Drift chambers e+ LAr calorimeter DIS s=4EeEp=100000 GeV2 M. Klein H1 27. 3. 2007

  32. Neutral and charged current data and heavy flavour data determine full set of pdf’s exp uncertainties of H1 pdfs based on HERA I data using Lagrange method for fit: x 0.01 0.4 0.65 xU 1% 3% 7% xD 2% 10% 30% M. Klein H1 27. 3. 2007

  33. M. Klein H1 27. 3. 2007

  34. HERA 2 Temple in Paestum, Italy before and after the luminosity upgrade HERA 1: 1991-2000, HERA 2: 2003-2007 --> data analysis till 2010+ M. Klein H1 27. 3. 2007

  35. Outlook M. Klein H1 27. 3. 2007

  36. The next huge step of accelerator based particle physics: 2007..2020 M. Klein H1 27. 3. 2007

  37. The LHC is a discovery machine based on developping QCD F.Gianotti ly 05 M. Klein H1 27. 3. 2007

  38. M. Klein H1 27. 3. 2007

  39. JINST 1 2006 P10001 • New Physics in the eq Sector leptoquarks, RP violating SUSY,.. • Quark-Gluon Dynamics and the Origin of Mass confinement and diffraction, the gluon • The Structure of Quantum Chromodynamics high density (CGC, instantons, odderons..), resumm’s • The Structure of the Proton substructure, parton correlations, transverse, uPDF’s • Precision for the LHC heavy flavour (b), strong coupling, partons • The Origin of the Quark Gluon Plasma partons in nuclei, deconfinement phase, CGC A possible future - ep Scattering at TeV Energies Design study for e ring in the LHC tunnel (LHeC) by 2009/10. 70 on 7000 GeV2 , 100 times HERA luminosity M. Klein H1 27. 3. 2007

  40. The H1 (+ ZEUS) experiment at HERA has been a major success • Its results have revolutionised the way we understand the structure of the proton and the underlying field theory • Many new fields were opened up such as the physics of high parton densities or the phenomenon of hard diffraction • Many unique measuremnets are being done at HERA, on the parton distributions, light, heavy quarks and gluons, with unprecedent precision and kinematic reach • Thus the results of HERA are of vital importance for understanding the data at the LHC which are imminent • A future DIS scattering experiment at TeV energy scales may be of fundamental importance, yet, the findings at the LHC will direct particle physics further • Within 100 years we went from the atomic nucleus at 10-14 m to pointlike quarks at 10-18 m, who knows what is ‘next door’? M. Klein H1 27. 3. 2007

  41. M. Klein H1 27. 3. 2007

  42. e e LEP _ e+ e-→ q q HERA e p → e X g2 M2 _FNAL_ pp → l l X q q • Proton • e Substructure of quarks? Leptoquarks? New physics? 4 Fermion Contact-Term HERA : Standard Model ok up to L = 5 TeV Symbiosis of ee, ep, pp M. Klein H1 27. 3. 2007

  43. The next huge step of collider detectors: ATLAS & CMS: 2007..2020 M. Klein H1 27. 3. 2007

  44. QCD represents ongoing exciting theory development,from hadronic interactions to a field theory of quarks and gluons • Landau 1955: „weak coupling electrodynamics is … fundamentally logically incomplete.” „within the limits of formal electrodynamics a point interaction is equivalent … to no interaction at all.” • Dyson 1960: “The correct theory will not be found within the next 100 years.” • Feynman 1961: “I still … do not subscribe to the philosophy of renormalization.” • Weinberg 1972, Gravitation + Cosmology: „we encounter theoretical difficulties beyond the range of modern statistical mechanics.” M. Klein H1 27. 3. 2007

  45. quarks carry only about 1/2of the nucleon momentum: The strong interaction gets larger at small distances [asymptotic freedom] and gluons carry half of proton’s momentum: QCD non Abelian qg field theory Nobel prize 2004: Gross, Politzer, Wilczek no doubt it “runs” - BUT how large is the coupling? and is the field so simple? HERA has a fundamental role to answer these ?’s M. Klein H1 27. 3. 2007

  46. M. Klein H1 27. 3. 2007

  47. M. Klein H1 27. 3. 2007

  48. New tracking detectors of H1 and ZEUS for HF physics in HERA II FST BST Online D* charm and beauty evt vtx (lo and hi y) eID (DVCS, J/Ψ, searches) FL Huge investments for high luminosity phase by H1 [and ZEUS] & fwd chambers CST MVD M. Klein H1 27. 3. 2007

  49. The QCD Lagrangian j … quark flavoursa,b,c … 3 coloursμ,ν … space-time F.Wilczek, Physics Today, August 2000. M. Klein H1 27. 3. 2007

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