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1 NUINT04 - Italy - Panofsky Prize Talk - 2004 Arie Bodek, University of Rochester The Structure of the Nucleon 3.5 decades of investigation 1968-1980.

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Presentation on theme: "1 NUINT04 - Italy - Panofsky Prize Talk - 2004 Arie Bodek, University of Rochester The Structure of the Nucleon 3.5 decades of investigation 1968-1980."— Presentation transcript:

1 1 NUINT04 - Italy - Panofsky Prize Talk - 2004 Arie Bodek, University of Rochester The Structure of the Nucleon 3.5 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 1980-2004 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, - Panofsky Prize 2004 2004-2010 Next generation NNLO QCD, Jefferson Lab Electron Scattering Experiments (JUPITER), MINERvA, Neutrino Superbeams. Neutrino Oscillations.

2 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 3 Prelude: SLAC MIT 1968-1974 Why do theorists like this experiment so much? - Victor Weisskopf

4 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 REGION Phys.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 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 6 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 FUNCTIONS Phys.Lett.B52:249,1974.& 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.

7 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 8 A : Nobel Prize 1990 - Friedman, Kendall, Taylor for 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 9 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. 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." Riordan and Bodek at the 1990 Nobel Ceremony

10 10 MIT SLAC DATA 1972 e.g. E0 = 4.5 and 6.5 GeV 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 ) What do The Frank Hertz” and “Rutherford Experiment” of the proton’ have in common? A: Quarks! And QCD

11 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 A, Bodek Panofsky Prize 2004 "For his 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 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-now G) Hadron Expt. p-Fe, pion-Fe and p-pbar, p-p colliders E379/E595 Hadronic 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-now G) Phenomenology(1999-F-now) e+e- Experiments The AMY e+e- Collaboration at TRISTAN/KEK (1982-1990) skip A lot of fun, but mostly unrelated to nucleon structure – except measurement of  S

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14 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 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 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 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. Goncharov et 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 18 H. Kim (Columbia PhD) et al. D.Harris et. al., (CCFR) MEASUREMENT OF  S (Q 2 ) FROM THE GROSS- LLEWELLYN SMITH SUM RULE. Phys. Rev. Lett. 81 (1998) 3595-3598 W.G. Seligman et al. (CCFR Columbia PhD), IMPROVED DETERMINATION OF  S FROM NEUTRINO NUCLEON SCATTERING. Phys. Rev. Lett. 79 (1997) 1213-1216.

19 19 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.86:2742-2745,2001

20 20 Neutrino Experiments REQUIRE good Hadron Calorimetry and Muon Energy calibration (~0.3%) 10 cm Fe Sampling, simultaneous neutrino running and hadron and muon test beams D.A. Harris, J. Yu et al( NuTeV-Rochester- FNAL) PRECISION CALIBRATION OF THE NUTEV CALORIMETER. UR-1561 Nucl. Inst. Meth. A447 (2000) W.K. Sakumoto et al. (CCFR-Rochester), CALIBRATION OF THE CCFR TARGET CALORIMETER. Nucl.Instrum.Meth.A294:179-192,1990. Developed Fe-scintillator compensating calorimeter. 3mx3m large counters with wavelength shifting readout

21 21 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 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

22 22 D Quark Distributions in Nuclei - Parallel Program at SLAC A.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. A. 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) A. 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)

23 23 Quark Distributions in Nuclei A. Bodek et al Phys.Rev.Lett.51:534, 1983 (SLAC Expt. E49, E87 empty tgt data 1970,1972)

24 24 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 NUCLEI Phys. 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.

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26 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. (1)Upgrade Cereknov Counter for ESA 8 GeV spectrometer - N2 with wavelength shifter on phototube (2)Upgrade Shower Counter (new segmented lead glass) (3)Upgraded tracking (wire chamber instead of scintillator) (4)Upgraded Radiative Corrections - Improved treatment using Bardin, Complete Mo-Tsai, test with different r.l. targets (5)Cross normalize all previous SLAC experiment to SLAC E140 by taking data in overlap regions.

27 27 Sridhara Rao Dasu, PRECISION MEASUREMENT OF X, Q2 AND A-DEPENDENCE OF R =  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/  T IN DEEP 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 BERYLLIUM TARGETS 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 28 Provided normalization and shape at lower Q2 for all DIS experiments

29 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 30 E: Proton-Antiproton (CDF/Dzero) collisions are actually parton-parton collisions (free nucleons)

31 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.

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34 34 Need to measure the W Asymmetry at high rapidity where there is no central tracking

35 35 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

36 36 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.

37 37 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. Proton-antiproton (CDF/Dzero) collisions-Measurement of d/u in the proton by using the W+- Asymmetry

38 38 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

39 39 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

40 40 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

41 41 Expected CDF Run II 2 fm-1 Drell Yan Mass Distribution Need even better PDFs Expected Z Rapidity 2 fm-1 CDF Rochester PhD Thesis (in progress) Ji Yeon Han Expected W Asymmetry 2 fm-1 CDF Rochester PhD Thesis (in progress ) Geum Bong Yu

42 42 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. Bodek Phys.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.

43 43 NNLO QCD+TM black Great Triumph of NNLO QCD Un-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 NNLO QCD+Tgt Mass works very well for Q2>1 GeV2

44 44 F 2, R comparison of NLO QCD+TM+HT black (Q 2 >1) (use QCD Renormalons forHT vs NLO QCD+TM only green Un-Ki Yang, A. Bodek Phys.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 NLO QCD + Target Mass + Renormalon HT works. ALSO a GREAT QCD TRIUMPH

45 45 Great Triumph of NNLO QCD Un-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

46 46 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.

47 47 Original approach (NNLO QCD+TM) was to explain the non-perturbative QCD effects at low Q 2, 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 Modified LO = Pseudo NNLO approach for low energies Applications to Jlab and Neutrino Oscillations P=M q m f =M* (final state interaction) Resonance, higher twist, and TM  w  = Q 2 +m f 2+ O(m f 2 -m i 2 ) + A M (1+(1+Q 2 / 2 ) ) 1/2 +B Xbj= Q 2 /2 M K factor to PDF, Q 2 /[Q 2 +C] A : initial binding/target mass effect plus higher order terms B: final state mass m f 2,  m  and photo- production limit ( Q 2 =0)

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52 52 Applications to Neutrino Oscillations at Low Energy MODELING DEEP INELASTIC CROSS-SECTIONS IN THE FEW GEV REGION.. Bodek, U.K. Yang Presented at 1st Workshop on Neutrino - Nucleus Interactions in the Few GeV Region (NuInt01), Tsukuba, Japan, 13-16 Dec 2001. Nucl.Phys.Proc.Suppl.112:70-76,2002 e: hep-ex/0203009 HIGHER TWIST, XI(OMEGA) SCALING, AND EFFECTIVE LO PDFS FOR LEPTON SCATTERING IN THE FEW GEV REGION. A Bodek, U.K. Yang Proceedings of 4th International NuFact '02 Workshop (Neutrino Factories Workshop on Neutrino Factories, London, England, 1-6 Jul 2002. J.Phys.G29:1899-1906,2003 MODELING NEUTRINO AND ELECTRON SCATTERING INELASTIC CROSS- SECTIONS IN THE FEW GEV REGION WITH EFFECTIVE LO PDFS IN LEADING ORDER. A. Bodek, U.K. Yang. 2nd International Workshop on Neutrino - Nucleus Interactions in the Few GeV Region (NUINT 02), Irvine, California, 12-15 Dec 2002. Nucl.Phys.Proc.Suppl. hep-ex/0308007 Invited Article to be published in Annual Review of Particle and Nuclear Science 2005

53 53 Work in Progress: Now working on the axial structure functions and next plan to work on resonance fits. G: Next: JUPITER at Jlab (Bodek,Keppel) will provided electron-Carbon (also e-H and e-D and other nuclei such as e-Fe) in resonance region. G: Next: MINERvA at FNAL (McFarland, Morfin) will provide Neutrino-Carbon data at low energies.

54 54 "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 It is an honor to be associated with these previous Panofsky Prize Winners 2003 William Willis 2002 Kajita Takaaki, Masatoshi Koshiba and Yoji Totsuka 2001 Paul Grannis 2000 Martin Breidenbach 1999 Edward H. Thorndike 1998David Robert Nygren 1997 Henning Schroder and Yuri Zaitsev 1996 Gail G. Hanson and Roy F. Schwitters 1995 Frank J. Sciulli 1994 Thomas J. Devlin and Lee G Pondrom 1993 Robert B. Palmer, Nicholas P. Samios, and Ralph P. Shutt 1992 Raymond Davis, Jr. and Frederick Reines 1991 Gerson Goldhaber and Francois Pierre 1990 Michael S. Witherell 1989 Henry W. Kendall, Richard E. Taylor, and Jerome I. Friedman 1988 Charles Y. Prescott

55 55 I would like to thank all of my collaborators over the past 3.5 decades The Electron Scattering SLAC-MIT collaboration at SLAC End Station A (In collaboration with Kendall, Friedman, Taylor, Coward, Breidenbach, Riordan, Elias, Atwood and others ) The Electron Scattering S E139, E140, E140x, NE8 collaboration at SLAC ESA and the Nuclear Physics NPAS injector at SLAC (in collaboration with ( Rock, Arnold, Bosted, Phillipone, Giokaris and others) The E379/E595 Hadronic Charm Production collaboration at Fermilab lab E (in collaboration with Barish, Wojcicki and others) The AMY e+e- Collaboration at TRISTAN/KEK (in collaboration with Steve Olsen and others) The CCFR-NuTeV Neutrino Collaboration at Fermilab Lab E(in collaboration with Barish, Sciulli, Shaevitz, Fisk, Merritt, Bernstein, McFarland and others) The CDF proton-antiproton Collaboration at Fermilab I am also looking forward to thanking my collaborators in The New Electron Scattering JUPITER Collaboration at Jefferson Lab and the new MINERvA Neutrino Collaboration at Fermilab (McFarland, Morfin, Keppel, Manly), and the CM-LHC collaboration when we get new results. And in particular I would like to thank the excellent graduate students and postdocs over the years, and Rochester Scientists Budd, deBarbaro, and Sakumoto.

56 56 Additional Slides

57 57 Kinematic Higher-Twist (target mass:TM)  TM = Q 2 / [M (1+ (1+Q 2 / 2 ) 1/2 ) ] –Proton Mass can be measured from the shape of low Q2 scaling violations The Target Mass Kinematic Higher Twist effects comes from the fact that the quarks are bound in the nucleon. They are important at low Q 2 and high x. They involve change in the scaling variable from x to  TM  and various kinematic factors and convolution integrals in terms of the PDFs for xF1, F 2 and xF 3 Above x=0.9, this effect is mostly explained by a simple rescaling in  TM  F 2 pQCD+TM (x, Q 2 ) =F 2 pQCD (  TM  Q 2  Compare complete Target-Mass calculation to simple rescaling in  TM Ratio F 2 (pQCD+TM)/F 2 pQCD Q 2 =15 GeV 2

58 58 Dynamic Higher Twist- Power Corrections- e.g. Renormalon Model (sum up all of QCD higher order terms) Use: Renormalon QCD model of Webber&Dasgupta- Phys. Lett. B382, 272 (1996), Two parameters a 2 and a 4. This model includes the (1/ Q 2 ) and (1/ Q 4 ) terms from gluon radiation turning into virtual quark antiquark fermion loops (from the interacting quark only, the spectator quarks are not involved). F 2 theory (x,Q 2 ) = F 2 PQCD+TM [1+ D 2 (x,Q 2 ) + D 4 (x,Q 2 ) ] D 2 (x,Q 2 ) = (1/ Q 2 ) [ a 2 / q (x,Q 2 ) ] *times function of x,q2 D 4 (x,Q 2 ) = (1/ Q 4 ) [ a 4 times function of x) ] In this model, the higher twist effects are different for 2xF 1, xF 3,F 2. With complicated x dependences which are defined by only two parameters a 2 and a 4. (the D 2 (x,Q 2 ) term is the same for 2xF 1 and, xF 3 ) Fit a 2 and a 4 to experimental data for F 2 and R=F L /2xF 1. F 2 data (x,Q 2 ) = [ F 2 measured +  F 2 syst ] ( 1+ N ) :  2 weighted by errors where N is the fitted normalization (within errors) and  F 2 syst is the is the fitted correlated systematic error BCDMS (within errors). q-qbar loops

59 59 Very high x F2 proton data (DIS + resonance) (not included in the original fits Q 2 =1. 5 to 25 GeV 2 ) NLO pQCD +  TM + higher twist describes very high x DIS F 2 and resonance F 2 data well. (duality works) Q 2 =1. 5 to 25 GeV 2 Q 2 = 25 GeV 2 Ratio F 2 data/F 2 pQCD Q 2 = 25 GeV 2 Ratio F 2 data/ F 2 pQCD+TM Q 2 = 25 GeV 2 Ratio F 2 data/F 2 pQCD+TM+HT F2 resonance Data versus F 2 pQCD+TM+HT pQCD ONLY pQCD+TM pQCD+TM+HT Q 2 = 25 GeV 2 Q 2 = 15 GeV 2 Q 2 = 9 GeV 2 Q 2 = 3 GeV 2 Q 2 = 1. 5 GeV 2 x  x  A w (w, Q 2 ) will account for interactions with spectator quarks

60 60 Look at Q 2 = 8, 15, 25 GeV 2 very high x data-backup slide* Pion production threshold A w ( w, Q 2 ) Now Look at lower Q 2 (8,15 vs 25) DIS and resonance data for the ratio of F2 data/( NLO pQCD +TM +HT} High x ratio of F2 data to NLO pQCD +TM +HT parameters extracted from lower x data. These high x data were not included in the fit. oThe Very high x(=0.9) region: It is described by NLO pQCD (if target mass and higher twist effects are included) to better than 10% Ratio F 2 data/F 2 pQCD+TM+HT Q 2 = 25 GeV 2 Q 2 = 15 GeV 2 Q 2 = 9 GeV 2

61 61 Initial quark mass m I and final mass,m F =m * bound in a proton of mass M Summary: INCLUDE quark initial Pt) Get  scaling (not x=Q 2 /2M ) for a general parton Model  Is the correct variable which is Invariant in any frame : q3 and P in opposite directions P= P 0 + P 3,M P F = P I 0,P I 3,m I P F = P F 0,P F 3,m F =m * q=q3,q0 Most General Case: (Derivation in Appendix)  ‘ w = [Q’ 2 +B] / [ M (1+(1+Q 2 / 2 ) ) 1/2 +A] (with A=0, B=0)  where2Q’ 2 = [Q 2 + m F 2 - m I 2 ] + { ( Q 2 +m F 2 - m I 2 ) 2 + 4Q 2 (m I 2 +P 2 t) } 1/2  Bodek-Yang: Add B and A to account for effects of additional  m 2  from NLO and NNLO (up to infinite order) QCD effects. For case  w with P 2 t =0  see R. Barbieri et al Phys. Lett. 64B, 1717 (1976) and Nucl. Phys. B117, 50 (1976) Special cases: (1) Bjorken x, x BJ =Q 2 /2M , -> x  For m F 2 = m I 2 =0 and High 2, (2) Numerator m F 2 : Slow Rescaling  as in charm production (3) Denominator : Target mass term  =Nachtman Variable  =Light Cone Variable  =Georgi Politzer Target Mass var. ( all the same  )

62 62 http://web.pas.rochester.edu/~icpark/MINERvA/

63 63 Correct for Nuclear Effects measured in e/ muon expt. Comparison of Fe/D F2 data In resonance region (JLAB) Versus DIS SLAC/NMC data In  TM (C. Keppel 2002).


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