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تسجيل مستخدم جديدInternal structure of the Lambda(1405) resonance probed in chiral unitary amplitude
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The internal structure of the resonant Lambda(1405) state is investigated based on meson-baryon coupled-channels chiral dynamics. We evaluate Lambda(1405) form factors which are extracted from current-coupled scattering amplitudes in meson-baryon degrees of freedom. Using several probe currents and channel decomposition, we find that the resonant Lambda(1405) state is dominantly composed of widely spread Kbar around N, with escaping pi Sigma component.
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Recent CLAS data for the pi Sigma invariant mass distributions (line-shapes) in the gamma p -> K^+ pi Sigma reaction are theoretically investigated. The line-shapes have peaks associated with the Lambda(1405) excitation. Our model consists of gauge i
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The electromagnetic mean squared radii, <r^2>_E and <r^2>_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 v
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The electric mean squared radii <r^2>_E of Lambda(1405) are calculated in the chiral unitary model. We describe the Lambda(1405) as a dynamically generated resonance fully in the octet meson and octet baryon scattering. We also consider ``Lambda(1405
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a(1405)n process favors the production of Lambda(1405) initiated by the KbarN channel. The present approach indicates that the Lambda(1405) resonance position is 1420 MeV rather than 1405 MeV in the pi Sigma invariant mass spectra of K- d to pi Sigma n reactions. This is consistent with an observed spectrum of the K^- d to pi^+ Sigma^- n with 686-844 MeV/c incident K^- by bubble chamber experiments done in the 70s. Our model also reproduces the measured Lambda(1405) production cross section.
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