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Search for the decay $K_S \to π^0γγ$

A. Lai
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Abstract

A search for the decay $K_S\toπ^0γγ$ has been made using the NA48 detector at the CERN SPS. Using data collected in 1999 during a 40-hour run with a high-intensity $K_S$ beam, an upper limit for the branching ratio $BR(K_S\toπ^0γγ, z\ge 0.2)<3.3\times\nolinebreak 10^{-7}$ has been obtained at 90% confidence level, where $z=m_{γγ}^2/m_{K_0}^2$.

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A. Lai. 2002-12-20. Search for the decay $K_S \to π^0γγ$. https://doi.org/10.1016/s0370-2693(03)00104-7

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