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Particle Physics pre -1968 simplistic view Many different models for Hadron Structure.

NUINT04 - Italy - Panofsky Prize Talk - 2004 Arie Bodek , University of Rochester The Structure of the Nucleon 3.5 decades of investigation.

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Particle Physics pre -1968 simplistic view Many different models for Hadron Structure.

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  1. NUINT04 - Italy - Panofsky Prize Talk - 2004Arie Bodek, University of RochesterThe Structure of the Nucleon3.5 decades of investigation • 1968-1980 Quarks (and gluons) -spin 1/2 point like Constituents Electron-Nucleon Scattering - Friedman, Kendall, Taylor, Panofsky Prize 1989,Nobel Prize of 1990. • A Detailed understanding of Nucleon Structure Required 3.5 Additional Decades of Experiments at Different Laboratories, New Detectors, Analysis Techniques and Theoretical Tools • 1980-2004LO QCD, anti-quarks, strange and charm quarks (hadronic charm production), individual PDFs , longitudinal structure function, quarks in nuclei , high statistics electron, muon and neutrino scattering experiments, NLO and NNLO QCD, origin of higher twist corrections, proton-antiproton collisions, W Asymmetry and d/u, Drell-Yan and Z rapidity distributions, application to neutrino oscillations, -Panofsky Prize 2004 • 2004-2010Next generation NNLO QCD, Jefferson Lab Electron Scattering Experiments (JUPITER), MINERvA, Neutrino Superbeams. Neutrino Oscillations.

  2. Particle Physics pre -1968 simplistic view • Many different models for Hadron Structure. • Quarks was considered more of a convenient way to model a symmetry rather than real particles (since none were ever observed and they had strange properties like 1/3 charge. • “Real Particle Physics” were done at hardon machine where “Resonances” and new particles were being studied and discovered (spectroscopy, group theory, partial wave analysis, resonances, Regge poles etc.) • Short Interlude – quarks “discovered” in electron scattering Particle Physics post 1973 simplistic view • J/psi-Charm and then Upsilon-Bottom discovered • “Real Particle Physics done at e+e- or hadron machine where new charm and bottom mesons and hadrons are discovered and studied, but now they are made of quarks (spectroscopy, partial wave analysis, resonances etc.). • “Real Particle Physics done at e+e- or hadron machine where new particles are NOT discovered (Supersymmetry, Lepto-quarks, Higgs, Heavy Leptons etc.

  3. Why do theorists like this experiment so much? - Victor Weisskopf Prelude: SLAC MIT 1968-1974

  4. 1968 - SLAC e-p scaling ==> Point like Partons in the nucleon (Bjorken/Feyman) MIT-SLAC group:Led by Friedman, Kendall, Taylor. • 1970-74 - Neutron/Proton ratio - Partons are quarks (Bodek PhD. MIT 1972) • A. Bodek et al., COMPARISONS OF DEEP INELASTIC ep AND en CROSS-SECTIONS.Phys.Rev.Lett.30:1087,1973. (SLAC Exp. E49) • A. Bodek et al., THE RATIO OF DEEP - INELASTIC en TO ep CROSS-SECTIONS IN THE THRESHOLD REGIONPhys.Lett.B51:417,1974 & (SLAC E87) • A. Bodek, COMMENT ON THE EXTRACTION OF NUCLEON CROSS SECTIONS FROM DEUTERIUM DATA, Phys. Rev. D8, 2331 (1973). N =d d u + sea 1/3 1/3 2/3 P = u u d + sea 2/3 2/3 1/3 Large x N/P -> 0.25 Explained by valence d/u [ (1/3) / (2/3)]2 =1/4 Small x : N/P=1 explained by sea quarks

  5. R=L/ T (small) quark are spin 1/2 E.M.Riordan PhD Thesis MIT 1973 E.M. Riordan, A. Bodek et al., EXTRACTION OF R = L/T FROM DEEP INELASTIC eP AND eD CROSS-SECTIONS. Phys.Rev.Lett.33:561,1974. A. Bodek et al.,EXPERIMENTAL STUDIES OF THE NEUTRON AND PROTON ELECTROMAGNETIC STRUCTURE FUNCTIONS. Phys.Rev.D20:1471-1552,1979.

  6. and A. Bodek et al.,. Phys.Rev.D20:1471-1552,1979 & **Note: much later we show Higher Twist come from NNLO QCD – see U. K. Yang, A. Bodek,STUDIES OF HIGHER TWIST AND HIGHER ORDER EFFECTS IN NLO AND NNLO QCD ANALYSIS OF LEPTON NUCLEON SCATTERING DATA ON F2 AND R L/T . Eur. Phys. J. C13 (2000) 241 245. • First observation of Scaling Violations SLAC -Higher Twist or QCD ? ** E. M. Riordan, A. Bodek et al., TESTS OF SCALING OF THE PROTON ELECTROMAGNETIC STRUCTURE FUNCTIONSPhys.Lett.B52:249,1974.&

  7. Integral of F2(x) did not add up to 1.0. Missing momentum attributed to “gluons”.Like Pauli’s missing energy in beta decay attributed to neutrinos*Gluons were “Discovered” in 1970, way before PETRA.Scatter shows F2(x, Q2) as expected from bremstrahlung of gluons by struck quarks in initial of final states.Scaling violations from “gluon” emission discovered in 1973, way before PETRA

  8. A: Nobel Prize 1990 - Friedman, Kendall, Taylorfor their pioneering investigations concerning deep inelastic scattering of electrons on protons and bound neutrons, which have been of essential importance for the development of the quark model in particle physics." Front row: Richard Taylor, Jerome Friedman, Henry Kendall. Second row:Arie Bodek, David Coward, Michael Riordan, Elliott Bloom, James Bjorken, Roger (Les) Cottrell, Martin Breidenbach, Gutherie Miller, Jurgen Drees, W.K.H. (Pief) Panofsky, Luke Mo, William Atwood. Not pictured: Herbert (Hobey) DeStaebler Graduate students in italics

  9. Michael Riordan has been awarded the 2002 Andrew Gemant Award by the American Institute of Physics for "skillfully conveying the excitement and drama of science and for clarifying important scientific ideas through his many books, articles and television programs." • E.M.Riordan PhD Thesis MIT 1973 One of the books that he wrote about the MIT-SLAC program titled "The Hunting of the Quark," (Simon & Schuster) won the AIP's Science Writing Award in 1988. Riordan wrote the "Hunting of the Quark" while holding the position of Scientist in the Department of Physics and Astronomy at Rochester (1984-1987), during which time he worked with Professor Arie Bodek's group on experiments E140 and E141 at the Stanford Linear Accelerator Center. Riordan and Bodek at the 1990 Nobel Ceremony

  10. e-P scattering A. Bodek PhD thesis 1972 [ PRD 20, 1471(1979) ] Proton Data Electron Energy = 4.5, 6.5 GeV Data ‘The electron scattering data in the Resonance Region is the “Frank Hertz Experiment” of the Proton. The Deep Inelastic Region is the “Rutherford Experiment” of the proton’ V. Weisskopf * (former faculty member at Rochester and MIT) when he showed these data at an MIT Colloquium in 1971 (* died April 2002 at age 93) MIT SLAC DATA 1972 e.g. E0 = 4.5 and 6.5 GeV What do The Frank Hertz” and“Rutherford Experiment” of the proton’ have in common? A: Quarks! And QCD

  11. "Physics is generally paced by technology and not by the physical laws. We always seem to ask more questions than we have tools to answer.” Wolfgang K. H. Panofsky • Questions in 1980-2004 LO QCD, anti-quarks, strange and charm quarks (hadronic charm production), individual PDFs , longitudinal structure function, quarks in nuclei , high statistics electron, muon and neutrino scattering experiments, NLO and NNLO QCD, origin of higher twist corrections, proton-antiproton collisions, W Asymmetry and d/u, Drell-Yan and Z rapidity distributions, application to neutrino oscillations, - • A Detailed understanding of Nucleon Structure Required 35 additional years of Experiments at Different Laboratories, New Detectors, Analysis Techniques and Theoretical Tools - AND also sorting out which experiments are right and which experiments are wrong • Panofsky Prize 2004 "For broad, sustained, and insightful contributions to elucidating the structure of the nucleon, using a wide variety of probes, tools and methods at many laboratories."

  12. Time Line Several Parallel Program over 35 years • Electron scattering e-P, e-N, e-A • Electron Scatt. SLAC-MIT SLAC E49, E87+more(1967-1973) A --------- D • Electron Scatt. SLAC E139, E140, E140x,E141, NE8(1983-1993) D • New Electron Scatt. JUPITER Expt at Jefferson Lab(2004-nowG) • Hadron Expt. p-Fe, pion-Fe and p-pbar, p-p colliders • E379/E595Hadronic Charm Production at Fermilab(1974-1983) B • CDF proton-antiproton Expt at Fermilab(1988---E----now) • CMS Experiment at CERN LHC(1995-----now) • Development of segmented tile-fiber and strip-fiber calorimetry ( 1990--------2004) • Neutrino Experiments • The CCFR-NuTeV Neutrino Expt at Fermilab(1974------- C-------2004) • New MINERvA Neutrino Expt at Fermilab(2004-nowG) • Phenomenology (1999-F-now) • e+e- Experiments • The AMY e+e- Collaboration at TRISTAN/KEK JAPAN(1982-1990) skip • A lot of fun, but mostly unrelated to nucleon structure – except measurement of S

  13. I would like to thank all of my collaborators over the past 3.5 decades • The Electron Scattering SLAC-MIT collaborationat SLAC End Station A (E49, E87) with Kendall, Friedman, Taylor, Coward, Breidenbach, Riordan, Elias, Atwood& others • The Electron Scattering E139, E140, E140x, NE8collaboration atSLAC ESA/ NPAS injector at SLAC (with Rock, Arnold, Bosted, Phillipone, Giokaris & others) • The E379/E595 Hadronic Charm with Barish, Wojcicki, Merrit. Fisk, Shaevitz& others) Productioncollaborationat Fermilab lab E • The AMY e+e- Collaboration at TRISTAN/KEK (with Steve Olsen& others) • The CCFR-NuTeV Neutrino Collaboration at Fermilab Lab E (with Barish, Sciulli, Shaevitz, Fisk, Smith,Merritt, Bernstein, McFarland and others) • The CDF proton-antiproton Collaboration at Fermilab • And in particular I thank the graduate students and • postdocs over the years, and Rochester Senior Scientists -- Budd, deBarbaro Sakumoto. • I am also looking forward ƒor more progress to be made with my new collaborators at the CMS-LHC experiment, The New Electron Scattering JUPITER Collaboration at Jefferson Lab,the new MINERvA Neutrino Collaboration • at Fermilab (McFarland, Morfin, Keppel, Manly),

  14. B: Hadronic Charm Production - Lab E Fermilab E379/E595 Single muons from charm, dimuons from Drell-Yan, vary target density to determine rate of muons from pion decays (1974-1983)

  15. Charm Quarks in the Nucleon • Rochester-Stanford-Caltech-Fermilab - Chicago Collaboration – Lab E (with Barry Barish, Frank Merritt, H.E. Fisk and Stan Wojcicki) Jack L. Ritchie, HADRONIC CHARM PRODUCTION BY PROTONS AND PIONS ON IRON.UR-861 (1983) Ph.D. Thesis (Rochester). Dexter Prize, U of Rochester - Now Professor at UT Austin A. Bodek et al.,A STUDY OF THE FORWARD PRODUCTION OF CHARM PARTICLE PAIRS IN P-FE AND PI- FE INTERACTIONS Phys. Lett. B 113:77,1982 (Fermilab Experiment E595, A. Bodek Spokesperson) Hadronic Charm Production is about 20 mb. Distribution is peaked at small Feynman x and is dominated by quark-quark and gluon-gluon processes. No Intrinsic Charm quarks in the nucleon - in contradiction with previously WRONG results reported by experiments at ISR

  16. C: Strange Quarks in the Nucleon - Caltech-Fermilab -Later- CCFR (Columbia -Chicago-Fermilab-Rochester) and -Later- NuTeV Neutrino Collaborations at Fermilab LAB E. Dimuon event

  17. Strange Quarks in the Nucleon - (Caltech-Fermilab, later CCFR Columbia -Chicago-Fermilab-Rochester) and NuTeV Neutrino Collaborations at Fermilab Karol Lang, AN EXPERIMENTAL STUDY OF DIMUONS PRODUCED IN HIGH-ENERGY NEUTRINO INTERACTIONS. UR-908 (1985) Ph.D. Thesis (Rochester) Now Professor at UT Austin K. Lang et al.(CCFR-Rochester PhD), NEUTRINO PRODUCTION OF DIMUONS. Z.Phys.C33:483,1987 (leading order analysis) A.O. Bazarko et al., (CCFR-Columbia PhD) DETERMINATION OF THE STRANGE QUARK CONTENT OF THE NUCLEON FROM A NEXT-TO-LEADING ORDER QCD ANALYSIS OF NEUTRINO CHARM PRODUCTION. Z.Phys.C65:189-198,1995 M. Goncharovet al. (NuTeV K.State PhD). PRECISE MEASUREMENT OF DIMUON PRODUCTION CROSS-SECTIONS IN MUON NEUTRINO FE AND MUON ANTI-NEUTRINO FE DEEP INELASTIC SCATTERING AT THE TEVATRON.Phys.Rev.D64:112006,2001 • The Strange Sea Anti-quarks are about 1/2 of the average of u and d sea - not SU3 Symmetric.

  18. W.G. Seligman et al. (CCFR Columbia PhD),IMPROVED DETERMINATION OF S FROM NEUTRINO NUCLEON SCATTERING. Phys. Rev. Lett. 79 (1997) 1213-1216. H. Kim (Columbia PhD) et al. D.Harris et. al., (CCFR) MEASUREMENT OFS (Q2) FROM THE GROSS- LLEWELLYN SMITH SUM RULE. Phys. Rev. Lett. 81 (1998) 3595-3598

  19. W.G. Seligman et al. (CCFR Columbia PhD),IMPROVED DETERMINATION OF S FROM NEUTRINO NUCLEON SCATTERING. Phys. Rev. Lett. 79 1213 (1997) H. Kim (CCFR Columbia PhD); D.Harris (Rochester) et. al.MEASUREMENT OFS (Q2) FROM THE GROSS- LLEWELLYN SMITH SUM RULE.Phys. Rev. Lett. 81, 3595 (1998)

  20. Precision Neutrino Experiments CCFR/NuTeV Un Ki Yang UR-1583,2000 Ph.D. Thesis, (Rochester) Lobkowicz Prize, U of R; URA Best Thesis Award Fermilab 2001 (now at Univ. of Chicago) Un-Ki Yang et al..MEASUREMENTS OF F2 AND XF3 FROM CCFR MUON NEUTRINO-FE AND MUON ANTI-NEUTRINO-FE DATA IN A PHYSICS MODEL INDEPENDENT WAY. By CCFR/NuTeV Phys.Rev.Lett.86, 2742,2001

  21. Neutrino Experiments REQUIRE good Hadron Calorimetry and Muon Energy calibration (~0.3%) 10 cm Fe Sampling, NuTeV simultaneous neutrino running and hadron and muon test beams D.A. Harris (Rochester), J. Yu et al NuTeV PRECISION CALIBRATION OF THE NUTEV CALORIMETER. UR-1561 Nucl. Inst. Meth. A447 (2000) W.K. Sakumoto(Rochester), et al. CCFR CALIBRATION OF THE CCFR TARGET CALORIMETER.Nucl.Instrum.Meth. A294:179-192,1990. CCFR Developed Fe-scintillator compensating calorimeter. 3mx3m large counters with wavelength shifting readout

  22. A lot of other physics (not related to nucleon structure) was investigated in the lab E E595 hadron program and the Lab E CCFR/NuTeV Neutrino Program --- a few examples: Some discoveries and precise measurements e.g. • Neutral Currents and electroweak mixing angle, Trimuons (CCFR/NuTeV) And also searches and limits Jack L. Ritchie UR PhD1983 Limits on Dzero to Dzero-bar mixing (E595 -1982) • Search for inclusive oscillations of muon neutrinos - Ian Stockdale,Rochester PhD Thesis CCFR-1982 • Search for New Heavy Leptons –CCFR -1990 Pawel de Barbaro, Rochester PhD Thesis 1990 • Search for exclusive oscillations of muon neutrinos to electron neutrinos-NuTeV – Sergei Avvakumov, Rochester PhD Thesis 2002

  23. D Quark Distributions in Nuclei - Parallel Program at SLAC Bodek,EMPTY TARGET SUBTRACTIONS AND RADIATIVE CORRECTIONS IN ELECTRON SCATTERING EXPERIMENTS, Nucl. Inst. Meth. 109 (1973). - factor of 6 increase in rate of empty target data by making empty target same radiation length as H2 and D2 targets; - used in SLAC E87 - more payoff later A. Bodek, J.L. Ritchie, FERMI MOTION EFFECTS IN DEEP INELASTIC LEPTON SCATTERING FROM NUCLEAR TARGETS, Phys.Rev.D23:1070,1981; Phys.Rev.D24:1400,1981. Bodek et al., ELECTRON SCATTERING FROM NUCLEAR TARGETS AND QUARK DISTRIBUTIONS IN NUCLEI. Phys.Rev.Lett.50:1431,1983.. - Use Empty Target Data from SLAC E87 (1972) Bodek et al., A COMPARISON OF THE DEEP INELASTIC STRUCTURE FUNCTIONS OF DEUTERIUM AND ALUMINUM NUCLEI.Phys.Rev.Lett.51:534,1983. Use empty target data from SLAC E49B (1970)

  24. Quark Distributions in Nuclei A. Bodek et al Phys.Rev.Lett.51:534, 1983 (SLAC Expt. E49, E87 empty tgt data 1970,1972)

  25. D Back to SLAC using High Energy Beam and the Nuclear Physics Injector NPAS - SLAC E139, E140, E140x, E141, NE8 • R.G. Arnold et al.,MEASUREMENTS OF THE A-DEPENDENCE OF DEEP INELASTIC ELECTRON SCATTERING FROM NUCLEIPhys. Rev. Lett.52:727,1984; • (initial results incorrect by 1% since two photon external radiative corrections for thick targets not initially accounted for. Found out later in SLAC E140) • J. Gomez et al., MEASUREMENT OF THE A-DEPENDENCE OF DEEP INELASTIC ELECTRON SCATTERING. Phys.Rev.D49:4348-4372,1994.

  26. SLAC E140, E140x - A. Bodek and S. Rock, Spokespersons. New Precision Measurement of R and F2, and Re-Analysis of all SLAC DIS data to obtain 1% precision. The issues: (1) Precise Values and Kinematic dependence of R needed to extract F2 from all electron muon and neutrino experiments. (2) Precise normalization of F2 needed to establish normalization of PDFs for all DIS experiments to 1%. Solution: SLAC E140 - New hardware, new theoretical tools. Upgrade Cereknov Counter for ESA 8 GeV spectrometer - N2 with wavelength shifter on phototube Upgrade Shower Counter (new segmented lead glass) Upgraded tracking (wire chamber instead of scintillator) Upgraded Radiative Corrections - Improved treatment using Bardin, Complete Mo-Tsai, test with different r.l. targets Cross normalize all previous SLAC experiment to SLAC E140 by taking data in overlap regions.

  27. Sridhara Rao Dasu,PRECISION MEASUREMENT OF X, Q2 AND • A-DEPENDENCE OFR = L/T AND F2 IN DEEP INELASTIC • SCATTERING. UR-1059 (Apr 1988) . Ph.D. Thesis. (Rochester) • SLAC E140 - winner of the Dexter Prize U of Rochester 1988 • (now Professor a U. Wisconsin, Madison) • S. Dasu(Rochester PhD )et al.,MEASUREMENT OF THE DIFFERENCE • IN R = L/T, andA/D IN DEEP INELASTIC ed, eFE AND eAu • SCATTERING. Phys.Rev.Lett.60:2591,1988; • S. Dasu et al., PRECISION MEASUREMENT OF R = L/T AND F2 IN DEEP INELASTIC ELECTRON SCATTERING. Phys.Rev.Lett.61:1061,1988; • S. Dasu et al., MEASUREMENT OF KINEMATIC AND NUCLEAR DEPENDENCE OF R = L/TINDEEP INELASTIC ELECTRON SCATTERING.Phys.Rev.D49:5641-5670,1994. • L.H. Tao, C. Keppel (American U PhD’s) et al., PRECISION MEASUREMENT OF R = L/T ON HYDROGEN, DEUTERIUM AND BERYLLIUMTARGETS IN DEEP INELASTIC ELECTRON SCATTERING. Z.Phys.C70:387,1996 • L.W. Whitlow (Stanford PhD), et al. ,A PRECISE EXTRACTION OF R = L/T FROM A GLOBAL ANALYSIS OF THE SLAC DEEP INELASTIC ep AND ed SCATTERING CROSS-SECTIONS.Phys.Lett.B250:193-198,1990. • L.W. Whitlow, et. al., PRECISE MEASUREMENTS OF THE PROTON AND DEUTERON STRUCTURE FUNCTIONS FROM A GLOBAL ANALYSIS OF THE SLAC DEEP INELASTIC ELECTRON SCATTERING CROSS-SECTIONS. Phys.Lett.B282:475-482,1992.

  28. Provided normalization and shape at lower Q2 for all DIS experiments

  29. SLAC E140 and the combined SLAC re-analysis provided the first precise values and kinematic dependence of R for use by all DIS experiments to extract F2 from differential cross section data

  30. E: Proton-Antiproton (CDF/Dzero) collisions are actually parton-parton collisions (free nucleons)

  31. Proton-Antiproton (CDF/Dzero) collisions are actually parton-parton collisions (free nucleons) This is why it is important to know the nuclear corrections for PDFs extracted from nucleons bound in Fe (neutrino) or in D2 (d versus u), when the PDFs are used to extract information from collider data In 1994 uncertainties in d/u from deuteron binding effects resulted in an error in the W mass extracted from CDF data of order 75 MeV. By the introduction of new techniques, one can use CDF data to provide independent constraints on free nucleon PDFs. A. Bodek, CONSTRAINTS ON PDFS FROM W AND Z RAPIDITY DISTRIBUTIONS AT CDF. Nucl. Phys. B, Proc. Suppl. 79 (1999) 136-138. In *Zeuthen 1999, Deep inelastic scattering and QCD* 136-138.

  32. Need to measure the W Asymmetry at high rapidity where there is no central tracking

  33. Qun Fan, Arie Bodek,A NEW TECHNIQUE FOR DETERMINING CHARGE AND MOMENTUM OF ELECTRONS AND POSITRONS USING CALORIMETRY AND SILICON TRACKING. In *Frascati 1996, Calorimetry in HEP*553- 560 Use silicon vertex detector to extrapolate electron track to the forward shower counters. Compare the extrapolated location to the centroid of the EM shower in a segmented shower counter. Energy of electron determined by the shower counter, Sign is determined by investigating if the shower centeroid is to the left or right of the extrapolated track, All hadron collider physics (Tevatron, LHC) with electrons and positrons can be done better without a central tracker . No Track misID Need Just silicon tracking and segmented EM +HAD calorimetry

  34. The d/u ratio in standard PDFs found to be incorrect. Now all new PDF fits include CDF W Asymmetry as a constraint. PDF error on W mass reduced to 10 MeV by using current CDF data.

  35. Proton-antiproton (CDF/Dzero) collisions-Measurement of d/u in the proton by using the W+- Asymmetry Mark Dickson,THE CHARGE ASYMMETRY IN W BOSON DECAYS PRODUCED IN P ANTI-P COLLISIONS. (1994) Ph.D.Thesis (Rochester). (now at MIT Lincoln Labs) Abe et al. (CDF-article on Rochester PhD Thesis)THE CHARGE ASYMMETRY IN W BOSON DECAYS PRODUCED IN P ANTI-P COLLISIONS AT 1.8-TEV. Phys.Rev.Lett.74:850-854,1995 Qun Fan, A MEASUREMENT OF THE CHARGE ASYMMETRY IN W DECAYS PRODUCED IN P ANTI-P COLLISIONS. Ph.D.Thesis (Rochester) (now at KLA-Tenor) Abe et al. (CDF article on Rochester PhD Thesis), A MEASUREMENT OF THE LEPTON CHARGE ASYMMETRY IN W BOSON DECAYS PRODUCED IN P ANTI-P COLLISIONS. Phys.Rev.Lett.81:5754-5759,1998.

  36. With this new technique, one can also significantly reduce the QCD background for very forward Z Bosons. Jinbo Liu, Measurement of d /dy for Drell-Yan e+e Pairs in the Z Boson Region Produced in Proton Anti-proton Collisions at 1.8 TeV. UR-1606, 2000 -Ph.D. Thesis (Rochester). (now at Lucent Technologies) T. Affolder et al. (CDF- article on Rochester PhD Thesis), MEASUREMENT OF d / dY FOR HIGH MASS DRELL-YAN E+ E- PAIRS FROM P ANTI-P COLLISIONS AT 1.8-TEV. Phys.Rev.D63:011101,2001. NLO QCD describes Z -y distributions better than LO QCD

  37. Knowledge of high x PDF is used as input to searches for new Z’ bosons in high-mass Drell-Yan cross sections and Forward-Backward Asymmetry (another use of forward tracking of electrons) Arie Bodek and Ulrich Baur IMPLICATIONS OF A 300-GEV/C TO 500-GEV/C Z-PRIME BOSON ON P ANTIP COLLIDER DATA AT 1.8-TEV. Eur.Phys.J.C21:607-611,2001 . T. Affolder et al.(CDF)Measurement of d / dM and forward backward charge asymmetry for high mass Drell-Yan e+ e- pairs from p anti-p collisions at 1.8-TeV.Phys.Rev.Lett.87:131802,2001

  38. Manoj Kumar Pillai, A SEARCH FOR NEW GAUGE BOSONS IN ANTI-P P COLLISIONS AT 1.8-TEV at CDF (1996). Ph.D.Thesis (Rochester) Abe et al.,(CDF) LIMITS ON QUARK - LEPTON COMPOSITENESS SCALES FROM DILEPTONS PRODUCED IN 1.8-TEV P ANTI-P COLLISIONS. Phys.Rev.Lett.79:2198-2203,1997. Abe et al. (CDF),MEASUREMENT OF Z0 AND DRELL-YAN PRODUCTION CROSS-SECTION USING DIMUONS IN ANTI-P P COLLISIONS AT 1.8-TEV. Phys.Rev.D59:052002,1999 Abe et al.(CDF)SEARCH FOR NEW GAUGE BOSONS DECAYING INTO DILEPTONS IN ANTI-P P COLLISIONS AT 1.8-TEV. Phys.Rev.Lett.79:2192-2197,1997 Knowing level of PDFs at High x Allows us to search for New Physics In High Mass Drell Yan Events

  39. Expected CDF Run II 2 fm-1 Drell Yan Mass Distribution Need even better PDFs Expected W Asymmetry 2 fm-1 CDF Rochester PhD Thesis (in progress) Geum Bong Yu Expected Z Rapidity 2 fm-1 CDF Rochester PhD Thesis (in progress) Ji Yeon Han

  40. F: Phenomenology: PUTTING it ALL TOGETHER The Great Triumph of NNLO QCD Origin of Higher Twist Effects, d/u and PDFs at large X – PARTON DISTRIBUTIONS, D/U, AND HIGHER TWIST EFFECTS AT HIGH X.Un-Ki Yang, A. BodekPhys.Rev.Lett.82:2467-2470,1999. STUDIES OF HIGHER TWIST AND HIGHER ORDER EFFECTS IN NLO AND NNLO QCD ANALYSIS OF LEPTON NUCLEON SCATTERING DATA ON F(2) AND R = (L) / (T). By Un-Ki Yang, A. Bodek . Eur.Phys.J.C13:241-245,2000 NNLO QCD +target mass corrections describes all of DIS data for Q2>1 GeV2 with NO Need for Higher Twists. GREAT TRIUMPH for QCD . Most of what was called low Q2 higher Twist are accounted for by higher order QCD.

  41. NNLO QCD+Tgt Mass works very well for Q2>1 GeV2 NNLO QCD+TM blackGreat Triumph of NNLO QCDUn-Ki Yang, A. Bodek . Eur.Phys.J.C13:241-245,2000 Size of the higher twist effect with NNLO analysis is really small (but not 0) a2= -0.009 (in NNLO) versus –0.1( in NLO) - > factor of 10 smaller, a4 nonzero

  42. NLO QCD + Target Mass + Renormalon HT works. ALSO a GREAT QCD TRIUMPH F2, R comparison of NLO QCD+TM+HT black(Q2>1) (use QCD Renormalons forHT vs NLO QCD+TM only greenUn-Ki Yang, A. BodekPhys.Rev.Lett.82:2467-2470,1999 PDFs and QCD in NLO + TM + QCD Renormalon Model for Dynamic HTdescribe the F2 and R data very well, with only 2 parameters. Dynamic HT effects are there but small

  43. Great Triumph of NNLO QCDUn-Ki Yang, A. Bodek . Eur.Phys.J.C13:241-245,2000 For High Statitics Hardon Collider Physics (run II, LHC), the next step is to extract NNLO PDFs. So declare victory and let theorists and PDF Professionals (MRST and CTEQ) make progress towards the next generation NNLO PDF fits for Tevatron and LHC

  44. For Tevatron and Run II, the path to greater precision is to perform NNLO QCD fits using both Q2>1 GeV2 DIS data and very high Q2 Tevatron results. In contrast, for applications to Neutrino Oscillations at Low Energy (down to Q2=0) the best approach is to use a LO PDF analysis (including a more sophisticated target mass analysis) and include the missing QCD higher order terms in the form of Empirical Higher Twist Corrections. Reason: For Q2>1 both Current Algebra exact sum rules (e.g. Adler sum rule) and QCD sum rules (e.g. momentum sum rule) are satisfied. This is why duality works in the resonance region (so use NNLO QCD analysis) For Q2<1, QCD corrections diverge, and all QCD sum rules (e.g momentum sum rule) break down, and duality breaks down in the resonance region. In contrast, Current Algebra Sum rules e,g, Adle sum rule which is related to the Number of (U minus D) Valence quarks) are valid.

  45. Modified LO = Pseudo NNLO approach for low energiesApplications to Jlab and Neutrino Oscillations Original approach (NNLO QCD+TM) was to explain the non-perturbative QCD effects at low Q2, but now we reverse the approach: Use LO PDFs and “effective target mass and final state masses” to account for initial target mass, final target mass, and missing higher orders q mf=M* (final state interaction) P=M Resonance, higher twist, and TM x w= Q2+mf2+O(mf2-mi2) +A Xbj= Q2 /2 Mn Mn (1+(1+Q2/n2) )1/2 +B A : initial binding/target mass effect plus higher order terms B: final state mass mf2 , Dm2, and photo- production limit (Q2 =0) K factor to PDF, Q2/[Q2+C]

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