Pontecorvo reactions in antiproton annihilation at rest in deuterium toπ0n,π0Δ0,ηn, andηΔ0

Using modularized NaI(Tl) detectors, we carried out a high statistics measurement of inclusive \ensuremath{\gamma}-ray, ${\ensuremath{\pi}}^{0}$, and \ensuremath{\eta} spectra, and determined the branching ratios or upper limits of Pontecorvo reactions $\mathrm{p\ifmmode\bar\else\textasciimacron\fi{}}d\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}n$, ${\ensuremath{\pi}}^{0}{\ensuremath{\Delta}}^{0}$, $\ensuremath{\eta}n$, and $\ensuremath{\eta}{\ensuremath{\Delta}}^{0}$ from the corresponding monochromatic peaks in them. The obtained branching ratios are $B(\mathrm{p\ifmmode\bar\else\textasciimacron\fi{}}d\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}n)=(1.03\ifmmode\pm\else\textpm\fi{}0.41)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, $B(\mathrm{p\ifmmode\bar\else\textasciimacron\fi{}}d\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{\ensuremath{\Delta}}^{0})=(4.67\ifmmode\pm\else\textpm\fi{}1.66)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$, $B(\mathrm{p\ifmmode\bar\else\textasciimacron\fi{}}d\ensuremath{\rightarrow}\ensuremath{\eta}n)l8.94\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}6}$ (95% C.L.), and $B(\mathrm{p\ifmmode\bar\else\textasciimacron\fi{}}d\ensuremath{\rightarrow}\ensuremath{\eta}{\ensuremath{\Delta}}^{0})l6.49\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$ (95% C.L.).