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arXiv · hep-ex/0204008

New measurements of the $η$ and $K^0$ masses

A. Lai·NA48 collaboration
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Abstract

New measurements of the $η$ and $K^0$ masses have been performed using decays to 3$π^0$ with the NA48 detector at the CERN SPS. Using symmetric decays to reduce systematic effects, the results $M(η) = 547.843\pm0.051$ MeV/c$^2$ and $M(K^0) = 497.625\pm0.031$ MeV/c$^2$ were obtained.

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A. Lai, NA48 collaboration. 2002-04-08. New measurements of the $η$ and $K^0$ masses. https://doi.org/10.1016/s0370-2693(02)01573-3

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