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

The Structure of the Nucleon 3 decades of investigation 1973-2004 - a personal perspective Arie Bodek , University of Rochester Madison, Wisconsin - Sept. 8, 2004. Particle Physics pre -1968 simplistic view Many different models for Hadron Structure.

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

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  1. The Structure of the Nucleon3 decades of investigation1973-2004 - a personal perspectiveArie Bodek, University of RochesterMadison, Wisconsin - Sept. 8, 2004

  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” done in hadron (proton) machines 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 e+e-, p-p • “Real Particle Physics now 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.). • Particle Physics Now simplistic view - “Real Particle Physics done at e+e- or hadron machine where new particles are NOT discovered (Supersymmetry, Lepto-quarks, Higgs, Heavy Leptons etc.

  3. The Structure of the Nucleon3 decades of investigation1973-2004a personal perspective In the beginning there was hadron Spectroscopy and quarks were only mathematical objects and then came the MIT-SLACelectron scattering experiments 1967-1973 And Quarks became Real Particles by 2000: Nucleon Structure is well understood and NNLO QCD works from Q2=1 GeV2 to the highest values currently accessible in hadron colliders. How did we get there?

  4. by 2000: Nucleon Structure is well understood and NNLO QCD works from Q2=1 GeV2 to the highest values currently accessible in hadron colliders. How did we get there? Like the majority of advances in High Energy Physics, progress in this area was accomplished by: Higher Energies (new accelerators and machines) And more importantly in combination with New experimental techniques - Higher PrecisionTo go beyond the Limitations/Brick Walls of old techniques Better understanding (new theoretical tools) Higher Luminosities (more statistics) Different probes (new beams)

  5. Gluons (bosons) =field particles of the color force Quarks (Fermions) - close to massless (MeV range) 1 GeV Mass If you want to be fussy, there are also a few photons from the electromagnetic interaction

  6. Inclusive e + p  e + X scattering Quarks are spin 1/2 Where Virtual photons are spin 1 and have mass =q2. Alternatively:

  7. Inclusive e + p  e + X scattering Single Photon Exchange Resonance Elastic DIS Where At high Q2 -> FL = 0 for spin 1/2 partons (virtual photon has spin 1, leading to a spin helicity flip) Alternatively:

  8. Why do theorists like this experiment so much? - Victor Weisskopf Prelude: SLAC MIT 1968-1974 Because they can understand the experimental setup- it is one of the few experiment where the apparatus and Feyman diagram look the same

  9. e-P scattering A. Bodek PhD thesis 1972 [ PRD 20, 1471(1979) ] Proton Data Electron Energy = 4.5, 6.5 GeV Data V. Weisskopf * (former faculty member at Rochester and at MIT when he showed these data at an MIT Colloquium in 1971 (* died April 2002 at age 93) Said MIT SLAC e-p DATA 1970 e.g. E0 = 4.5 and 6.5 GeV ‘The Deep Inelastic Region is the“Rutherford Experiment”of the proton. The electron scattering data in the Resonance Region is the“Frank Hertz Experiment”of the Proton. What do The Frank Hertz” and“Rutherford Experiment” of the proton’ have in common? A: Quarks! And QCD

  10. 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.” (1967-73) Described in detail in"The Hunting of the Quark," (Simon & Schuster) Michael Riordan AIP Science Writing Award 1988 & AIP Andrew Gemant Award 2003 Important to share the excitement of science with the public 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

  11. COMPARISONS OF DEEP INELASTIC ep AND en CROSS-SECTIONS AB et al Phys. Rev. Lett. 30: 1087,1973. (SLAC Exp. E49 PhD thesis)-First resultNext Step higher precision • THE RATIO OF DEEP - INELASTIC en TO ep CROSS-SECTIONSINTHE THRESHOLD REGION AB et al Phys.Lett.B51:417,1974 ( SLAC E87) 1968 - SLAC e-p scaling ==> Point like Partons in the nucleon 1970-74 - Neutron/Proton ratio - Partons are fractionally charged (quarks) PRL referees - nothing substantially new over 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 PARTONS ARE QUARKS ! [ (1/3) / (2/3)]2 =1/4 Small x : N/P=1 explained by sea quarks F2N F2P Scaling-> Point like PARTONS 2/3 F2P 1/4 1 2 x x

  12. RP 3 R=L/ T (small) quarks are spin 1/2 ! EXTRACTION OF R = L/T FROM DEEP INELASTIC eP AND eD CROSS-SECTIONS. E. Riordan, AB et al Phys.Rev.Lett.33:561,1974. EXPERIMENTAL STUDIES OF THE NEUTRON AND PROTONELECTROMAGNETIC STRUCTURE FUNCTIONS. AB et alPhys.Rev.D20:1471-1552,1979. BUT what is the x and Q2 Dependence of R? What is x, Q2 dependence of u, d, s, c quarks and antiquarks?

  13. 4. Integral of F2(x) =0.5 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, much before PETRABUT what is their x Distributions? F2P 4 F2N 5. Scatter shows F2(x, Q2) as expected from bremstrahlung of gluons by struck quarks in initial of final states. BUT QCD NOT FULLY FORMALIZED YET F2D 5

  14. Scaling violations from quark binding effects (Higher Twist, Target mass) go like powers in 1/Q2 QCD scaling violations from gluon emission are logarithmic with Q2

  15. Scaling violationsSEEN in 1974, Are they deviations from Parton Model e.g. from “gluon” emission, or are they just at Low Q2 F2P Extracted from Rosenbluth separations • Next Higher Precision: First observation of Scaling Violations SLAC • E. M. Riordan, AB et al TESTS OF SCALING OF THE PROTON ELECTROMAGNETIC STRUCTURE FUNCTIONSPhys.Lett.B52:249,1974(more detail in AB et al Phys.Rev.D20:1471-1552,1979 Note in 2000. We show that Higher Twist come from Target Mass + NNLO QCD STUDIES OF HIGHER TWIST AND HIGHER ORDER EFFECTS IN NLO AND NNLO QCD ANALYSIS AB, UK Yang. Eur. Phys. J. C13 (2000) 241 245. 1974: PRL Referees - obviously these are uninteresting low Q2 effects

  16. "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 1972-2000 Anti-quarks,strange , charm quarks in nucleons , individual PDFs(u,d,qbar,gluonsQ2,x dependence)R=longitudinal structure function (x,Q2), quarks in nuclei , origin of scaling violations- low Q2 higher twist or QCD?, • A Detailed understanding of Nucleon Structure Required Initiating Measurements at Different Laboratories, New Detectors, New Analysis Techniques and Theoretical Tools - AND also sorting out which experiments are right and which experiments are wrong - incremental but steady progress. Meanwhile: the J/Psi was discovered in 1974 --->and the age of Spectroscopy returned; and then came the Upsilon and there was more spectroscopy to be done. - but a few people continued to study the nucleon.

  17. How are Parton Distributions (PDFs) Extract from various data at large momentum transfer (e// and other expts.) PDF(x)= Valence and sea H and D d/u Also Drell Yan, jets etc

  18. Also thanks to our Collaborators over the past 3.5 decades +FUTURE ( Blue awarded Panofsky Prize) • The Electron Scattering SLAC-MIT collaboration at SLAC End Station A (E49, E87) with Kendall, Friedman, Taylor, Coward, Breidenbach, Riordan, Elias, Atwood& others (1967-1973) • The Electron Scattering E139, E140, E140x, NE8 collaboration at SLAC ESA/ NPAS injector at SLAC (with Rock, Arnold, Bosted, Phillipone, Giokaris & others) (1983-1993) • The E379/E595 Hadronic Charm:with Barish, Wojcicki, Merrit. Fisk, Shaevitz& others) Production collaboration at Fermilab labE(1974-83) • The AMY e+e- Collaboration at TRISTAN/KEK (with Steve Olsen& others) (1982-1990) • The CCFR(W)-NuTeV Neutrino Collaboration at Fermilab Lab E (with(1974-2004)Barish, Sciulli, Shaevitz, Fisk, Smith,Merritt, Bernstein, McFarland and others) • The CDF proton-antiproton Collaboration at Fermilab (1988- • And in particular I thank the graduate students and 2004) • postdocs over the years, and Rochester Senior ScientistsBudd, deBarbaro Sakumoto. • +more progress to be made with collaborators at the CMS-LHC experiment,(1995-->) • The New Electron Scattering JUPITER Collaboration at • Jefferson Lab,& the new MINERvA Neutrino (1993--> • Collaboration at Fermilab(McFarland, Morfin, Keppel, Manly),

  19. Fermilab CCFR/NuTeV v-N Expt. -N (data) CDF Collider Expt MINERvA Expt KEK AMY @ TRISTAN JHF Conclusion Rochester CERN-N, v-N (data) CMS Collider J-lab e-N (Data) JUPITER Expt. SLAC ESA SLAC NPAS programs e-N Data

  20. Caltech (->Columbia)- Chicago - Fermilab - Rochester -(Wisconsin) • The CCFR(W)-NuTeV Neutrino Collaboration at Fermilab Lab E (1974-2004) - separate quark and antiquark distributions, Valence and Sea • Barish, Sciulli, Shaevitz, Fisk, Smith,Merritt, Bernstein, McFarland and others) • . • Budd, deBarbaro Sakumoto • Rochester Senior Scientists V-A Weak Interaction => difference between quarks and anti-quarks (Neutrinos are left handed and antineutrinos right handed)

  21. Neutrino physics is information rich NC- Electroweak CC- quarks antiquarks, PDFs and QCD dimuons- Charm and Strange quarks

  22. 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

  23. . CCFR(W) Neutrino detector used as a final state muon identifier in a high energy proton beam - what is the origin of prompt muon productxion in hadronic collision P+N-> D--> Muon 30% and P+N - > Dimuons 70% 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)

  24. 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 • 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 ISRresults. • Intrinsic C(x) = 0 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 B: Are there charm quarks in nucleon ?

  25. Dimuon event C: Strange Quarks in the Nucleon - Caltech-Fermilab --> CCFR (Columbia -Chicago-Fermilab-Rochester) and -Later- NuTeV Neutrino Collaborations at Fermilab LAB E. K The Strange SeaAnti-quarks are about 1/2 of the average of u and d sea - i.e Not SU3 Symmetric. Karol Lang, AN EXPERIMENTAL STUDY OFDIMUONS PRODUCED IN HIGH-ENERGY NEUTRINO INTERACTIONS.UR-908 (1985)Ph.D. Thesis (Rochester) Now Professor at UT Austin Most recently M.Goncharov and D. Mason (NuTeV PhDs)

  26. Precision High Statistics Neutrino Experiments at Fermilab - Valence, Sea, Scaling Violations, gluons F2 xF3 , Precise sGLS sum rule (Q2 dependence) GLS( q2) dependence s 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)

  27. 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 -FE DATA IN A PHYSICS MODEL INDEPENDENT WAY. By CCFR/NuTeV Phys.Rev.Lett.86, 2742,2001 Same PDFs should describe all processes Resolved 10% to 20% difference between  and  data Experiment vs Theory: Ratio of F2 (neutrino)/F2 (muon)

  28. A lot of other physics (not related to nucleon structure) was investigated in the lab E E595 hadron program and the Lab E CCFR (W) /NuTeV Neutrino Program --- a few examples: Some discoveries and precise measurements e.g. • Neutral Currents and electroweak mixing angle, Trimuons (CCFR(w)/NuTeV) And also searches and limits (A few non-discoveries) • Limits on Dzero to Dzero-bar mixing (E595) • Search for New Heavy Leptons – Pawel de Barbaro, Rochester PhD Thesis 1990 • Search for inclusive oscillations of muon neutrinos - Ian Stockdale, Rochester PhD Thesis 1984 • Search for exclusive oscillations of muon neutrinos to electron neutrinos – Sergei Avvakumov, Rochester PhD Thesis 2002

  29. D Quark Distributions in Nuclei - New Parallel Program at SLAC AB, J Ritchie FERMI MOTION EFFECTS IN DEEP INELASTIC LEPTON SCATTERING FROM NUCLEAR TARGETS, Phys.Rev.D23:1070,1981; Phys.Rev.D24:1400,1981. 1983 (conference proceeding) surprising report of difference between Iron and Deuterium muon scattering data from the European Muon Collaboration (EMC) Disagreement with Fermi Motion Models. Physics Archeology - Use 12 and 13 year old SLAC Empty target data to check on this AB, 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 ELECTRON SCATTERING FROM NUCLEAR TARGETS AND QUARK DISTRIBUTIONS IN NUCLEI. AB et al Phys.Rev.Lett.50:1431,1983.. - Use Empty Target Data from SLAC E87(1972)(initially rejected by Phys. Rev, Letters) IRON A COMPARISON OF THE DEEP INELASTIC STRUCTURE FUNCTIONS OF DEUTERIUM AND ALUMINUM NUCLEI. AB et al Phys.Rev.Lett.51:534,1983. Use empty target data from SLAC E49B(1970) ALUMINUM

  30. Quark Distributions in NucleiAB et al Phys. Rev. Lett. 51: 534, 1983 (SLAC Expt. E49, E87 empty tgt data 1970,1972) EMC PRL Referees: (1) How can they claim that there are quarks in nuclei + (2) Obviously uninteresting multiple scattering of electrons in a nucleus- --> later accepted by PRL editors.

  31. 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. Back to SLAC End Station A to measure effect on various nuclei

  32. 1983: The field of quark distributions in nuclei hit a brick wall: 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 - SLAC E140, E140x - . New Precision Measurement of R and F2, and Re-Analysis of all SLAC DIS data to obtain 1% precision. New hardware, new theoretical tools 1 month run worth years of data, IMPACT all DIS Experiments Past and Future. Upgrade Cerenkov Counter for ESA 8 GeV spectrometer - N2 with wavelength shifter on phototube Upgrade Shower Counter from lead-acrylic (to segmented lead glass) Upgraded tracking (wire chambers instead of scintillator-hodoscope) Upgraded Radiative Corrections - Improved treatment using Bardin, Complete Mo-Tsai, test with different r.l. targets ( to 0.5%) Cross normalize all previous SLAC experiment to SLAC E140 by taking data in overlap regions.(Re-analysis with upgraded rad corr).

  33. 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 on the faculty at 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 eAuSCATTERING. 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 (American U PhD) 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.

  34. Provided normalization and shape at lower Q2 for all DIS experiments- constrain systematic errors on high energy muon experiments - Perturbative QCD with and without target mass (TM) effects

  35. Current Status of Unpolarised SFs From Bodek (2000) Overall, F2 is well measured over 4 orders of magnitude,

  36. SLAC E140 and the combined SLAC re-analysis provided the first precise values and kinematic dependence of R Related to F2/2xF1 for use by all DIS experiments to extract F2 from differential cross section data R

  37. Proton-Antiproton (CDF/Dzero) collisions are actually parton-parton collisions (free nucleons) Measure W mass from Transverse mass of electrons from W decays W->electron-neutrino

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

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

  40. Proton-antiproton collisions (CDF)- 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) Qun Fan, A MEASUREMENT OF THE CHARGE ASYMMETRY IN W DECAYS PRODUCED IN P ANTI-P COLLISIONS. Ph.D.Thesis (Rochester 1996) (now at KLA-Tenor

  41. Need to measure the W Decay lepton Asymmetry at high rapidity where there is no central tracking Unfortunately W’s decay to electrons and neutrinos - Decay lepton asymmetry is a convolution of the W production Asymmetry

  42. A NEW TECHNIQUE FOR DETERMINING CHARGE AND MOMENTUM OF ELECTRONS AND POSITRONS USING CALORIMETRY AND SILICON TRACKING. AB and Q. Fan In *Frascati 1996, Calorimetry in HEP*553- 560 (First used in AMY) 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 mis-ID Need Just silicon tracking and segmented EM +HAD calorimetry -Adapted by CMS-LHC

  43. 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.

  44. With this new technique, one can also significantly reduce the QCD background for very forward Z Bosonsproduced in hadron colliders. 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 -> more statistics - Tevatron run II & LHC

  45. 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

  46. Knowing level of PDFs at High x Allows us to search for New Physics In High Mass Drell Yan Events 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 A few non-discoveries

  47. 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) Expected Z Rapidity 2 fm-1 CDF Rochester PhD Thesis (in progress) Ji Yeon Han

  48. F: Phenomenology: PUTTING it ALL TOGETHER The Great Triumph of NNLO QCD Origin of Higher Twist Effects, d/u and PDFs at large X – 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. PARTON DISTRIBUTIONS, D/U, AND HIGHER TWIST EFFECTS AT HIGH X. AB, UK YangPhys.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). AB, UK YangEur.Phys.J.C13:241-245,2000

  49. NNLO QCD+Tgt Mass works very well for Q2>1 GeV2 NNLO QCD+TM blackGreat Triumph of NNLO QCD. AB, UK YangEur.Phys.J.C13:241-245,2000 Size of the higher twist effect with NNLO analysis is very small a2= -0.009 (in NNLO) versus –0.1( in NLO) - > factor of 10 smaller, a4 nonzero F2P R F2D

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