Matter-enhanced antineutrino flavor transformation and supernova nucleosynthesis

Matter-enhanced antineutrino flavor transformation between ν${\mathrm{¯}}_{\mathit{e}}$ and ν${\mathrm{¯}}_{\mathrm{\mu }\left(\mathrm{\tau }\right)}$ can occur in supernovas if the vacuum masses for these species satisfy ${\mathit{m}}_{\nu \mathrm{¯}\mathit{e}}$>${\mathit{m}}_{\nu \mathrm{¯}\mathrm{\mu }\left(\mathrm{\tau }\right)}$. For δ${\mathit{m}}^2$>1 ${\mathrm{eV}}^2$, such flavor transformation can affect the electron fraction ${\mathit{Y}}_{\mathit{e}}$ in the neutrino-heated supernova ejecta. We point out that such flavor transformations will not drive ${\mathit{Y}}_{\mathit{e}}$>0.5 at the r-process nucleosynthesis epoch in the best available supernova model for such nucleosynthesis. Consequently, there is no obvious conflict between the matter-enhanced antineutrino flavor transformation ν${\mathrm{¯}}_{\mathit{e}\mathrm{\parallel }}$ν${\mathrm{¯}}_{\mathrm{\mu }\left(\mathrm{\tau }\right)}$ and r-process nucleosynthesis in the neutrino-heated supernova ejecta.