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DOE OSTI · 1462191

Exploring Hyperon Structure with Electromagnetic Transverse Densities

Hiller Blin, Astrid N.·Alarcon, Jose Manuel·Vicente Vacas, Manuel J.·Weiss, Christian
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Abstract

Here, we explore the structure of the spin-1/2 flavor-octet baryons (hyperons) through their electromagnetic transverse densities. The transverse densities describe the distribution of charge and magnetization at fixed light-front time and enable a spatial representation of the baryons as relativistic systems. At peripheral distances b~1/M π the transverse densities are computed using a new method that combines chiral effective field theory (χEFT) and dispersion analysis. The peripheral isovector densities arise from two-pion exchange, which includes the ρ resonance through elastic unitarity. The isoscalar densities are estimated from vector meson exchange (ω,Φ). We find that the “pion cloud” in the charged Σ hyperons is comparable to the nucleon, while in the Ξ it is suppressed. The Λ–Σ 0 transition density is pure isovector and represents a clear manifestation of peripheral two-pion dynamics.

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74 ATOMIC AND MOLECULAR PHYSICS

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Hiller Blin, Astrid N., Alarcon, Jose Manuel, Vicente Vacas, Manuel J., Weiss, Christian. 2018-07-18. Exploring Hyperon Structure with Electromagnetic Transverse Densities. https://doi.org/10.1007/s00601-018-1434-3

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