کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1873824 | 1531679 | 2007 | 108 صفحه PDF | دانلود رایگان |
We review the description of the lowest-energy nucleon excitation—the Δ(1232)Δ(1232)-resonance. Much of the recent experimental effort has been focused on the precision measurements of the nucleon-to-ΔΔ transition by means of electromagnetic probes. We confront the results of these measurements with the state-of-the-art calculations based on chiral effective-field theories (EFT), lattice Quantum Chromodynamics (QCD), large-NcNc relations, perturbative QCD, and QCD-inspired models. We also discuss the link of the nucleon-to-ΔΔ form factors to generalized parton distributions (GPDs). Some of the theoretical approaches are reviewed in detail, in particular, recent dynamical and unitary-isobar models of pion electroproduction, which are extensively used in the interpretation of experiments. A novel extension of chiral EFTs to the energy domain of the ΔΔ-resonance is reviewed. The two-photon exchange effects in the electroexcitation of the ΔΔ-resonance are addressed.
Journal: Physics Reports - Volume 437, Issues 5–6, January 2007, Pages 125–232