We have studied the production of neutral $\Sigma^{0}$ baryons in the reaction p+Nb at an incident proton energy of $E_{\textrm{kin}}$ = 3.5 GeV.
The measurement has been performed with the HADES spectrometer at GSI, Darmstadt. $\Sigma^{0} \rightarrow \Lambda^{0} \gamma$ and $\Sigma^{0} \rightarrow \Lambda e^{+} e^{-}$
decays were identified via the charged decay $\Lambda \rightarrow p \pi^{-}$ coincident to $e^{+}e^{-}$ pairs from external or internal gamma conversion. A total of
net 220 $\Sigma^0$ candidates has been extracted. We present here the analysis method and the signal verification in simulations.