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arXiv · 0803.4068

Electromagnetic mean squared radii of Lambda(1405) in chiral dynamics

T. Sekihara·T. Hyodo·D. Jido
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Abstract

The electromagnetic mean squared radii, _E and _M, of Lambda(1405) are calculated in the chiral unitary model. We describe the excited baryons as dynamically generated resonances in the octet meson and octet baryon scattering. We evaluate values of _E and _M for the Lambda(1405) on the resonance pole and obtain their complex values. We also consider Lambda(1405) obtained by neglecting decay channels. For the latter case, we obtain negative and larger absolute electric mean squared radius than that of typical ground state baryons. This implies that Lambda(1405) has structure that K^- is widely spread around p.

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T. Sekihara, T. Hyodo, D. Jido. 2008-10-21. Electromagnetic mean squared radii of Lambda(1405) in chiral dynamics. https://doi.org/10.1016/j.physletb.2008.09.023

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