The excited baryon spectrum: What have we learned?

A complete theory of strong interactions must describe the excited baryon spectrum as well as the structure of prominent states, which reflects the dynamics of nonperturbative QCD. Beyond the discriminating power of exclusive single- and double-pion electroproduction, the ω channel provides an additional probe of high-mass excited states. The current analysis provides preliminary differential and integrated cross sections of ω electroproduction off the proton from W = 1.7 to 3.2 GeV and Q2 = 1.5 to 5.5 GeV2. The data was collected by JLab's CLAS detector during two run periods and comprises the largest sample of exclusive resonance-region ω electroproduction ever analyzed. Preliminary Legendre decomposition of the cross sections supports previous indications of s-channel contributions to cross sections in the resonance region.

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Mapping chiral symmetry breaking in the excited baryon spectrum

Physical Review D ◽

10.1103/physrevd.94.054006 ◽

2016 ◽

Vol 94 (5) ◽

Cited By ~ 7

Author(s):

Pedro Bicudo ◽

Marco Cardoso ◽

Felipe J. Llanes-Estrada ◽

Tim Van Cauteren

Keyword(s):

Symmetry Breaking ◽

Chiral Symmetry ◽

Chiral Symmetry Breaking ◽

Baryon Spectrum ◽

Excited Baryon

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Applications of AdS/CFT Duality to QCD

International Journal of Modern Physics A ◽

10.1142/s0217751x06032009 ◽

2006 ◽

Vol 21 (04) ◽

pp. 762-768 ◽

Cited By ~ 4

Author(s):

Stanley J. Brodsky ◽

Guy F. de Téramond

Keyword(s):

Scattering Amplitudes ◽

Quantum Chromodynamics ◽

Power Law ◽

Mass Parameter ◽

Light Quark ◽

Form Factors ◽

Light Front ◽

Baryon Spectrum ◽

Conformal Theory ◽

Counting Rules

Even though quantum chromodynamics is a broken conformal theory, the AdS/CFT correspondence has led to important insights into the properties of QCD. For example, as shown by Polchinski and Strassler, dimensional counting rules for the power-law falloff of hadron scattering amplitudes follow from dual holographic models with conformal behavior at short distances and confinement at large distances. We find that one also obtains a remarkable representation of the entire light-quark meson and baryon spectrum, including all orbital excitations, based on only one mass parameter. We also show how hadron light-front wavefunctions and hadron form factors in both the space-like and time-like regions can be predicted.

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