On the Sigma^0 --> Lambda^0 + gamma decay in the Effective quark model with chiral U(3)xU(3) symmetry

A. N. Ivanov; A. Ya. Berdnikov; Ya. A. Berdnikov; M. Faber; V. A. Ivanova; V. F. Kosmach; A. V. Nikitchenko; N. I. Troitskaya

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arXiv · hep-ph/0512176

On the Sigma^0 --> Lambda^0 + gamma decay in the Effective quark model with chiral U(3)xU(3) symmetry

A. N. Ivanov·A. Ya. Berdnikov·Ya. A. Berdnikov·M. Faber·V. A. Ivanova·V. F. Kosmach·A. V. Nikitchenko·N. I. Troitskaya

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Abstract

We analyse the angular distributions of the Sigma^0 --> Lambda^0 + gamma decay rate in the laboratory and in the rest frame of the Sigma^0 - hyperon in the dependence on baryon polarizations. We calculate the dynamical polarization vector of the Lambda^0 - hyperon. Within the Effective quark model with chiral U(3) x U(3) symmetry (PRC 59, 451 (1999)) we calculate the transition magnetic moment mu_(Sigma^0 Lambda^0). The theoretical value mu_(Sigma^0 Lambda^0) = - 1.62, measured in nuclear magnetons, agrees well with the experimental data |mu^(\exp)_(Sigma^0 Lambda^0)| = (1.61 +/-0.08) and the theoretical result, predicted within the naive quark model mu_(Sigma^0 Lambda^0) = (\sqrt{3}/4)(mu_(Sigma^-) - mu_(Σ^+)) = (- 1.57 +/- 0.01).

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A. N. Ivanov, A. Ya. Berdnikov, Ya. A. Berdnikov, M. Faber, V. A. Ivanova, V. F. Kosmach, A. V. Nikitchenko, N. I. Troitskaya. 2005-12-14. On the Sigma^0 --> Lambda^0 + gamma decay in the Effective quark model with chiral U(3)xU(3) symmetry. https://arxiv.org/abs/hep-ph/0512176

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