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تسجيل مستخدم جديدOn the Sigma^0 --> Lambda^0 + gamma decay in the Effective quark model with chiral U(3)xU(3) symmetry
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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_(Sigma^+)) = (- 1.57 +/- 0.01).
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