Formation of the pseudoscalars<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi>π</mml:mi></mml:mrow><mml:mrow><mml:mn>0</mml:mn></mml:mrow></mml:msup></mml:mrow></mml:math>,<i>η</i>, and η’ in the reaction<i>γγ→γγ</i>

The Crystal Ball detector has been used at the DORIS II storage ring at DESY to study the reaction ${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\rightarrow}${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\gamma}*\ensuremath{\gamma}*\ensuremath{\rightarrow}${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$\ensuremath{\gamma}\ensuremath{\gamma}, where X is a narrow resonance with mass between 100 and 3000 MeV. Formation of ${\ensuremath{\pi}}^{0}$, \ensuremath{\eta}, and \ensuremath{\eta}' mesons is observed, and the following meson partial widths are obtained: ${\mathrm{\ensuremath{\Gamma}}}_{\mathrm{\ensuremath{\pi}}0\mathrm{\ensuremath{\Gamma}}0\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}}$=7.7\ifmmode\pm\else\textpm\fi{}0.5\ifmmode\pm\else\textpm\fi{}0.5 eV, ${\mathrm{\ensuremath{\Gamma}}}_{\mathrm{\ensuremath{\eta}}\mathrm{\ensuremath{-}}\ensuremath{\gamma}\ensuremath{\gamma}}$=0.514\ifmmode\pm\else\textpm\fi{}0.017\ifmmode\pm\else\textpm\fi{}0.035 keV, and ${\mathrm{\ensuremath{\Gamma}}}_{\mathrm{\ensuremath{\eta}}\mathcal{'}\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}}$=4.7\ifmmode\pm\else\textpm\fi{}0.5\ifmmode\pm\else\textpm\fi{}0.5 keV. No other narrow resonances are observed, and upper limits are given for the product ${\ensuremath{\Gamma}}_{X\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}}$${B}_{X\ensuremath{\rightarrow}\ensuremath{\gamma}\ensuremath{\gamma}}$. .AE