Precision measurement of the $\Xi^{0}$ mass and the branching ratios of the decays $\Xi^{0}\rightarrow\Lambda\gamma$ and $\Xi^{0}\rightarrow\Sigma^{0}\gamma$

A new precision measurement of the $\Xi^{0}$ mass has been performed at the NA48 experiment at the CERN SPS. The value obtained is $[1314.82 \pm 0.06_{(stat.)} \pm 0.2_{(syst.)}]$MeV/c$^{2}$. The branching ratios of $\Xi^{0}$ radiative decays have been measured as: Br($\Xi^{0} \to \Lambda\gamma) = [1.90 \pm 0.34_{(stat)} \pm 0.19_{(syst.)}] \cdot 10^{−3}$ and Br($\Xi^{0} \to \Sigma^{0}\gamma)=[3.14 \pm 0.76_{(stat.)} \pm 0.32_{(syst.)}] \cdot 10^{−3}$.