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Measurement of the quadratic slope parameter in the K_L -> 3π^0 decay Dalitz plot

NA48 Collaboration
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Abstract

A value of (-6.1 +- 0.9_{stat} +- 0.5_{syst})*10^{-3} is obtained for the quadratic slope parameter h in the K_L -> 3π^0 decay Dalitz plot at the NA48 experiment at the CERN SPS. The result is based on 14.7*10^6 fully reconstructed K_L -> 3π^0 -> 6γdecays. This is the most precise measurement of any of the Dalitz plot slope parameters in the charged and neutral kaon decays so far.

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NA48 Collaboration. 2001-06-20. Measurement of the quadratic slope parameter in the K_L -> 3π^0 decay Dalitz plot. https://doi.org/10.1016/s0370-2693(01)00861-9

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