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The Structure of the Nucleon 3 decades of investigation 1973-2004 Arie Bodek , University of Rochester. Like the majority of advances in High Energy Physics, progress in this area was accomplished by: Higher Precision (new experimental techniques) Better understanding (new theoretical tools)
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The Structure of the Nucleon3 decades of investigation1973-2004Arie Bodek, University of Rochester Like the majority of advances in High Energy Physics, progress in this area was accomplished by: Higher Precision (new experimental techniques) Better understanding (new theoretical tools) Higher Luminosities (more statistics) Different probes (new beams) Higher Energies (new accelerators and machines) Session S5 - DPB/DPF Prize Session., Monday afternoon, 14:30 - 15:06 May 03 Governor's Square 14, Adam's Mark Hotel
The Structure of the Nucleon3 decades of investigation1973-2004Arie Bodek, University of Rochester 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 In 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?
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
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 x x
RP 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? and of d, u, quarks and antiquarks?
Integral of F2(x) did not add up to 1.0. Missing momentum attributed to “gluons”. GLUONS “DISCOVERED”BUT what is their x Distributions?Like Pauli’s missing energy in beta decay attributed to neutrinos*Gluons were “Discovered” in 1970, much before PETRA.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 F2P F2N F2D
Scaling violationsSEEN in 1973, 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. Riorday, 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 2003. 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. PRL Referees - obviously these are uninteresting low Q2 effects
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
"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.
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
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-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),
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
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 ?
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)
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 OFS (Q2) FROM THE GROSS- LLEWELLYN SMITH SUM RULE.Phys. Rev. Lett. 81, 3595 (1998)
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)
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 surprising report of difference between Iron and Deuterium muon scattering data from the European Muon Collaboration (EMC) Disagreement with Fermi Motion Model 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) 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)
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.
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
SLAC E140, E140x - . 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 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).
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, andA/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.
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
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
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 Deuterium (d versus u), when the PDFs are used to extract information from collider data 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. 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 andQCD* 136-138.
E: Proton-Antiproton (CDF/Dzero) collisions are actually parton-parton collisions (free nucleons)
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) (now at KLA-Tenor
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
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 misID Need Just silicon tracking and segmented EM +HAD calorimetry
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.
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
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
Great Triumph of NNLO QCD. AB, UK YangEur.Phys.J .C13:24,2000 First extraction of (NNLO PDFs)/(NLO PDFs) ratio Low x NNLO PDFs 2% higher than NLO PDFs High x NNLO PDFs 10% lower than NLO PDFs For High Statistics 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
CONCLUSION: Progress is made in finite incremental steps as new techniques and methods lead to greater precision (making what was impossible -> possible) A factor of 2 reduction in error each generation (either statistical or systematic) is worth it, and one can always go back and re-analyze old data with better corrections to reduce systematic errors In 4 generations of experiments (2)4 =16 fold reduction in errors 2000: Nucleon Structure well understood. NNLO QCD works from Q2=1 to the highest values currently accessible. Hadron colliders are actually quark and gluon colliders with known and well understood PDFs.
2000-2004->2010 (The high Energy Frontier): For Tevatron and Run II and LHC , the path to greater precision is using: NNLO QCD fits with both Q2>1 GeV2 DIS data & very high Q2 Collider Data.-Good for theorists • 2000-2004->2010 (The Low Energy Frotier) • Applications to Neutrino Oscillations at Low Energy (Nucleon and Nuclear Structure down to Q2=0) • Here 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. * Vector Part well understood - Phenomenology AB+U K Yang (2002-2004) • - Axial Part needs further investigation - • future Data 2004-2008 (JUPITER, e-N at Jlab) • MINERvA, v-N at Fermilab)
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 +A Xbj= Q2 /2 Mn Mn (1+(1+Q2/n2) )1/2 +B K factor to PDF, Q2/[Q2+C] MODELING DEEP INELASTIC CROSS-SECTIONS IN THE FEW GEV REGION.AB, UK YangNucl.Phys.Proc.Suppl.112:70,2002 A : initial binding/target mass effect plus higher order terms B: final state mass mf2 , Dm2, and photo- production limit (Q2 =0)
Describes all vector structure functions from Q2=0 to 100,000 GeV2
Maintaining the colorful Program G:Next: JUPITER at Jlab (Bodek,Keppel) will provided electron-Carbon (also e-H and e-D and other nuclei such as e-Fe) data in resonance region, and final states (Manly)-summer 04 +05. G : Next: MINERvA at FNAL (McFarland, Morfin) will provide Neutrino-Carbon data at low energies. G: CDF Run II (now) and CMS, high statistics W’s Z’s and Drell Yan Work in Progress: Phenomenology: Now working on the axial structure functions and plan to work on resonance fits for both electrons/neutrinos
Time Line Several Parallel Program over 30 years • Electron scattering e-P, e-N, e-A * (Kendal Friedman Taylor- Panofsky & Nobel Prizes) • 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) • {Develop segmented tile-fiber and strip-fiber calorimetry ( 1990------2004) • CMS Experiment at CERN LHC (1995-----now) • Neutrino Experiments * (Frank Sciulli Panofsky Prize) • 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 JAPAN (1982-1990) skip • A lot of fun, but mostly unrelated to nucleon structure – except measurement of S • And Shower Electron tracking with with segmented calorimetry
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
NLO QCD + Target Mass + Renormalon HT works. A GREAT QCD TRIUMPH F2, R comparison of NLO QCD+TM+HT black(Q2>1)(use QCD Renormalons for HT vs NLO QCD+TMonly greenAB, UK YangPhys.Rev.Lett.82,1999 PDFs and QCD in NLO + TM + QCD Renormalon Model for Dynamic HT describe the F2 and R data very well, with only 2 parameters. Dynamic HT effects are there but small
"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 2004 Arie Bodek (Rochester) 2003 William Willis (Columbia) 2002 Kajita Takaaki, Masatoshi Koshiba and Yoji Totsuka 2001 Paul Grannis (SUNY SB) Martin Breidenbach (SLAC) 1999 Edward H. Thorndike (Rochester) 1998 David Robert Nygren (Berkeley) 1997 Henning Schroder and Yuri Zaitsev 1996 Gail G. Hanson and Roy F. Schwitters 1995 Frank J. Sciulli (Columbia) 1994 Thomas J. Devlin (Rutgers) and Lee G Pondrom (Wisconsin) It is an honor to be associated with these previous Panofsky Prize Winners 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 (Santa Barbara) 1989 Henry W. Kendall, Richard E. Taylor, and Jerome I. Friedman (MIT/SLAC) 1988 Charles Y. Prescott (SLAC)
Applications to Neutrino Oscillations at Low Energy MODELING DEEP INELASTIC CROSS-SECTIONS IN THE FEW GEV REGION.A. 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