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Alexander A. Savin PowerPoint Presentation
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Alexander A. Savin

Alexander A. Savin

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Alexander A. Savin

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  1. Rapidity Gaps and Survival Probability Experimental Introduction Alexander A. Savin Multi-jet final states and energy flows working group HERA LHC Workshop, CERN, 26-27 March 2004

  2. Hard Diffraction (hard scale: jets production, W etc ) Rapidity gap: HERA TEVATRON SD DD DPE A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  3. Events signature at HERA 27.5 GeV e 820/920 GeV P Large Rapidity Gap Leading Proton Spectrometer (LPS, ZEUS) Forward Proton Spectrometer (FPS, H1) Ep’/Ep = 1 A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  4. Event simulation LO: ARIADNE LEPTO PYTHIA RAPGAP Parton Level Hadron Level CDM+LUND etc GEANT Detector Simulation NLO: DISENT DISASTER++ MEPJET NLOJETS Uncertainties: pdf hadronisation detector A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  5. Jet Finding i j HERA TEVATRON Longitudinally invariant kT cluster algorithm Cone algorithm with Inclusive mode, combine if: Out-of-cone correction: an addition to the jet Pt (R) Exclusive mode: combine until A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  6. QCD fits and Pomeron parton density functions universal partonic cross section parton distributions flux A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  7. D(3) PDF was assigned to the Pomeron and evolved using DGLAP equation QCD-fit to F 2 Z is the fractional momentum of Pomeron carried by the struck parton A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  8. Diffractive DIS Dijets Data Using PDF’s from LO fits to F2D and RAPGAP H1 Shape is o.k. Normalization? 1996-97 A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  9. Diffractive PHP Dijet Data IP p H1 1996-97 Gap survival factor? GAL Generalised Area Low model for pp diff.scattering (fits to inclusive DIS ee data). A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  10. Tevatron vs HERA LO fits: HERA predictions for the rate of dijet production in pp exceed the observed rate by a factor 10! _ Even more for DPE: CDF measured: Predicted using H1 fit 6: A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  11. Tevatron vs Tevatron: Double Pomeron Exchange vs SD A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  12. DPE Higgs production H A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  13. Jets with rapidity gap - interjet energy flow - Infrared safe way to study gaps-between-jets ; - pQCD/npQCD at 1 GeV ; PHP Total minijet energy in the gap g-remnant P- remnant 2 high-Et jets 2p Jet R Gap Jet R 0 -2.4 2.4 h A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  14. Jets with rapidity gap - interjet energy flow Gap Fraction Expectation for behavior of Gap Fraction (J. D. Bjorken, V. Del Duca, W.-K. Tang) Dijet events with Rapidity Gap (Egap-dep.) fgap All Dijet events fgapsinglet 2 fgapn-s 3 4 A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  15. The Gap Fraction H1 Color singlet added A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  16. The Gap Fraction ZEUS New ressumation A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27

  17. Summary A lot of interesting data, theoretical input is needed (see next talk!) A.Savin, Rapidity Gaps and Survival Probability, Experimental Introduction, HERA LHC Workshop, CERN, March 26-27