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arXiv · hep-ex/0012031

A Measurement of the Branching Ratio and Asymmetry of the Decay Cascade^0-->Sigma^0/gamma

A. Alavi-Harti
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Abstract

We have studied the rare weak radiative hyperon decay Cascade0-->Sigma0/gamma in the KTeV experiment at Fermilab. We have identified 4045 signal events over a background of 804 events. The dominant Cascade0-->Lambda/pi0 decay, which was used for normalization, is the only important background source. An analysis of the acceptance of both modes yields a branching ratio of BR(Cascade0-->Sigma0/gamma)=(3.34 +/- 0.05 +/- 0.09) x 10^(-3). By analyzing the final state decay distributions, we have also determined that the Sigma0 emission asymmetry parameter for this decay is alpha = -0.63 +/- 0.09.

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A. Alavi-Harti. 2000-12-11. A Measurement of the Branching Ratio and Asymmetry of the Decay Cascade^0-->Sigma^0/gamma. https://doi.org/10.1103/physrevlett.86.3239

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