Puzzles in Hadronic Physics and Novel Quantum Chromodynamics Phenomenology

Abstract

We review some outstanding puzzles and experimental anomalies in hadron physics that appear to challenge conventional wisdom and, in some cases, the foundations of QCD. We also discuss possible solutions and propose new tests and experiments that could illuminate the underlying physics and novel phenomenological features of QCD. In some cases, new perspectives for QCD physics have emerged.

35 pages, pdf only

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• Light-Cone Wavefunctions and the Intrinsic Structure of Hadrons

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• Light-Front Holographic QCD and Emerging Confinement
• Explanation and Prediction of Observables using Continuum Strong QCD
• Exotic hadrons: review and perspectives
• Tsallis Fits to pT Spectra and Multiple Hard Scattering in pp Collisions at the LHC
• A review of the intrinsic heavy quark content of the nucleon
• Novel Six-Quark Hidden-Color Dibaryon States in QCD
• Measurement of the forward-backward asymmetry in top quark-antiquark production in ppbar collisions using the lepton+jets channel
• Scattering in Time-Dependent Basis Light-Front Quantization
• The QCD Dynamics of Tetraquark Production
• Can we understand an auxetic pion-photon transition form factor within QCD? BaBar faces Belle
• Extra Spin Asymmetries From the Breakdown of TMD-Factorization in Hadron-Hadron Collisions
• A direct probe of the intrinsic charm content of the proton
• Non-perturbative quantum time evolution on the light-front
• Study of $Z$ bosons produced in association with charm in the forward region
• Search for doubly-heavy dibaryons in a quark model
• Applications of Basis Light-Front Quantization to QED
• Transverse Momentum Spectra of Pions at LHC Energies
• The fundamental scale of QCD
• CORSIKA Implementation of Heavy Quark Production and Propagation in Extensive Air Showers
• Anomalous pion production induced by nontrivial topological structure of QCD vacuum
• Proton's Electromagnetic Form Factors from a Non-Power Confinement Potential
• Asymmetry in ${\Lambda }_b$ and ${\bar{\Lambda }}_b$ production
• Revisiting the $B_s^{(\ast )}$-Meson Production at the Hadronic Colliders
• The Forward Physics Facility at the High-Luminosity LHC
• Potentials on the conformally compactified Minkowski spacetime and their application to quark deconfinement
• Novel QCD Phenomena at JLab
• $f$-mode Oscillations for Hyperons and H-dibaryons in Neutron Stars