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arXiv · 1604.06746

Universal Effective Hadron Dynamics from Superconformal Algebra

Abstract

An effective supersymmetric QCD light-front Hamiltonian for hadrons composed of light quarks, which includes a spin-spin interaction between the hadronic constituents, is constructed by embedding superconformal quantum mechanics into AdS space. A specific breaking of conformal symmetry inside the graded algebra determines a unique effective quark-confining potential for light hadrons, as well as remarkable connections between the meson and baryon spectra. The results are consistent with the empirical features of the light-quark hadron spectra, including a universal mass scale for the slopes of the meson and baryon Regge trajectories and a zero-mass pion in the limit of massless quarks. Our analysis is consistently applied to the excitation spectra of the $π, ρ, K, K^*$ and $ϕ$ meson families as well as to the $N, Δ, Λ, Σ, Σ^*, Ξ$ and $Ξ^*$ in the baryon sector. We also predict the existence of tetraquarks which are degenerate in mass with baryons with the same angular momentum. The mass of light hadrons is expressed in a universal and frame-independent decomposition in the semiclassical approximation described here.

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BibTeXRIS

Stanley J. Brodsky, Guy F. de Téramond, Hans Gunter Dosch, Cédric Lorcé. 2016-07-01. Universal Effective Hadron Dynamics from Superconformal Algebra. https://doi.org/10.1016/j.physletb.2016.05.068

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