What Makes Strong QCD so Intriguing Ralf W. Gothe Graduate Lecture Series Universidad Michoacana de San Nicolás de Hidalgo Morelia, México, Marcha 12-15, 2018 My talk will be about the electroexcitation of nucleon resonances. This conferences is all about nucleons and baryons. Nathan Isgur has been a strong supporter of a nucleon research program at this laboratory. He formulated the importance of studies of the nucleon in 3 remarks he made at the N*2000 conferences in this auditorium: Essentials: Phase Space Cells, Coherence, Form Factors, … QCD Knowns: Deep Inelastic Scattering and Heavy Quark Systems QCD Unknowns: Nonperturbative QCD, Mass, Confinement, … This work is supported in parts by the National Science Foundation under Grant PHY 1505615.

Essentials from Nuclei to Quarks Ralf W. Gothe Graduate Lecture Series Universidad Michoacana de San Nicolás de Hidalgo Morelia, México, Marcha 12-15, 2018 My talk will be about the electroexcitation of nucleon resonances. This conferences is all about nucleons and baryons. Nathan Isgur has been a strong supporter of a nucleon research program at this laboratory. He formulated the importance of studies of the nucleon in 3 remarks he made at the N*2000 conferences in this auditorium: Essentials: Phase Space Cells, Coherence, Form Factors, … QCD Knowns: Deep Inelastic Scattering and Heavy Quark Systems QCD Unknowns: Nonperturbative QCD, Mass, Confinement, … This work is supported in parts by the National Science Foundation under Grant PHY 1505615.

E = mc2 Matter E=CV/2= 1 kJ m=E/c2 = 1.1.10-11 g C=80mF and V=5kV defibrillator E=CV/2= 1 kJ m=E/c2 = 1.1.10-11 g C=80mF and V=5kV d=1mm A=9000m2

Resolution Momentum Space Volume No inplane asymmetry

Double Slit Experiment = Photons Dt Wilking, Dz Michelson, Dx Hanbury Brown Twiss

Quasi-Elastic Electron Scattering K1m K2m Km P1m P2m N * N Localization ↔ Statistical Motion Phase Space & Phase Space Cells Fermi Momentum Fermi Broadening

Quasi-Elastic Electron Scattering

Coherent Electron Scattering

Form Factors and Charge Density Distribution

Form Factors and Charge Density Distribution

Form Factors and Charge Density Distribution

Form Factors and Charge Radii

Nucleon Form Factors Dirac magnetic dipole moment of a structureless spin 1/2 particle

Nucleon Form Factors 12

n bonds and n+1 constituents Form Factor Scaling n 6n n bonds and n+1 constituents

Deep Inelastic Scattering DIS

Point-Like Constituents ~ Q-8 PRL 23 (1969) 935 Prog. in Phys. 4 (1982)

Point-Like Constituents with Spin 1/2 PRL 22 (1969) 156 F1 structure function vanishes for spin-zero particles Callan-Gross relation follows for spin ½ Dirac Particles

Quasi-Elastic Scattering Quark-Hadron Duality PRL 16 (1970) 1140, PR D4 (1971) 2901 E.D. Bloom and F.J. Gilman W = 1.9 GeV E’ = 17.6 GeV n = 2.37 GeV Q2 = 1.72 GeV mq = 0.36 GeV mq = Q2/2n pF = 0.67 GeV rF = 0.79 fm DrF = hc *√9p/2 DpF PR D22 (1975) 1884 S. Stein et al.

Quark Charges and Momentum Distributions x.v x.q= x.s/2 Isospin Symmetry For backward scattering: neutrinos couple only to quarks and antineutrinos only to antiquarks, due to angular momentum and helicity conservation.

Di-Quarks in Deep Inelastic Scattering Nucl. Phys. B371 (1992) 3 = 2/3 = 1/4 Only the u valence quark carries large x in the proton and the only the d valence quark in the neutron.

Di-Quarks in Deep Inelastic Scattering Arrington et al. (2009) Bonus, PRL 108, 142001 (2012) 1 1/4 Holt and Roberts, arXiv:1002.4666v3 (2010) = 1/4 Only the u valence quark carries large x in the proton and the only the d valence quark in the neutron.

Heavy Quark Systems Alpha_bb = 0.189 PDG

Hydrogen Atom Coulomb Potential 100 B= -13.6 eV U= -27.2 eV ah 𝑈𝑝=− 𝑐 𝑟𝑏 𝑇= ∆𝑝2 2𝑚 = ( )2 2𝑚𝑐2𝑟𝑏2 hc <𝑇> =−< 𝑈𝑝 2 >

Heavy Quark Systems Virial Theorem: as= 3/4 hc/rminmc2 = 0.25 for rcc = 0.4fm and as= 3/4 hc/rminmc2 = 0.18 for rbb = 0.2fm Alpha_bb = 0.189 PDG

Dirac Delta Function, Fields, Potentials, and Sources = 0 only for n = -2 and r > 0

Heavy Quark Systems Bali et al. he-la/0512018 Infinetly heavy sources, u,d,ubar,dbar sea-quarks with strange quark mass, which shows that the string breaks at 2 times the strange quark mass APS 09GHPCDRoberts.pdf