Observation of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mrow><mml:mover><mml:mrow><mml:mi>p</mml:mi></mml:mrow><mml:mrow><mml:mi>¯</mml:mi></mml:mrow></mml:mover></mml:mrow></mml:mrow><mml:mi>p</mml:mi><mml:mo>→</mml:mo><mml:mn>2</mml:mn><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>at Rest: Evidence Concerning s-State Annihilation

We have identified the annihilation mode $\overline{p}p\ensuremath{\rightarrow}2{\ensuremath{\pi}}^{0}$ for antiprotons stopping in liquid hydrogen at a rate which is 0.15 (\ifmmode\pm\else\textpm\fi{}20%) times that reported for $\overline{p}p\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$. This indicates that about 40% of all annihilations into $2\ensuremath{\pi}$ take place from odd-orbital atomic $\overline{p}p$ states, in contrast to the usual assumption that annihilation from the $s$ state predominates.