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A QCD Sum Rule Approach to the $s\to dγ$ Contribution to the $Ω^-\to Ξ^-γ$ Radiative Decay

M. Nielsen·L. A. Barreiro·C. O. Escobar·R. Rosenfeld
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Abstract

QCD sum rules are used to calculate the contribution of short-distance single-quark transition $s\rightarrow d γ$, to the amplitudes of the hyperon radiative decay, $Ω^-\rightarrow Ξ^-γ$. We re-evaluate the Wilson coefficient of the effective operator responsible for this transition. We obtain a branching ratio which is comparable to the unitarity limit.

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M. Nielsen, L. A. Barreiro, C. O. Escobar, R. Rosenfeld. 1995-09-14. A QCD Sum Rule Approach to the $s\to dγ$ Contribution to the $Ω^-\to Ξ^-γ$ Radiative Decay. https://doi.org/10.1103/physrevd.53.3620

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