| Autor: |
Oset, E., Inoue, T., Vacas, M.J. Vicente, Ramos, A., Bennhold, C. |
| Předmět: |
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| Zdroj: |
International Journal of Modern Physics A: Particles & Fields; Gravitation; Cosmology; Nuclear Physics; Jan2003, Vol. 18 Issue 3, p387, 10p |
| Abstrakt: |
The s-wave meson-baryon interaction in the S = -1, S = 0 and S = -2 sectors is studied by means of coupled channels, using the lowest-order chiral Lagrangian and the N/D method or equivalently the Bethe-Salpeter equation to implement unitarity. This chiral approach leads to the dynamical generation of the Λ(1405), Λ(1670) and Σ(1620) states for S = -1, the N[sup *](1535) for S = 0 and the Ξ(1620) for S = -2. We look for poles in the complex plane and extract the couplings of the resonances to the different final states. This allows identifying the Λ(1405) and the Λ(1670) resonances with &Kmacr;N and KΞ quasibound states, respectively. Our results are found to be incompatible with the measured properties of the Ξ(1690) resonance, thus ruling this state out as the remaining member of this octet of dynamically generated resonances. We therefore assign ½[sup -] for the spin and parity of the Ξ(1620) resonance as the S = -2 member of the lowest-lying ½[sup -] octet. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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