Matter-enhanced antineutrino flavor transformation and supernova nucleosynthesis

Matter-enhanced antineutrino flavor transformation between ν̄e and ν̄μ(τ) can occur in supernovas if the vacuum masses for these species satisfy mν̄e>mν̄μ(τ). For δm2>1 eV2, such flavor transformation can affect the electron fraction Ye in the neutrino-heated supernova ejecta. We point out that such flavor transformations will not drive Ye>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 ν̄eν̄μ(τ) and r-process nucleosynthesis in the neutrino-heated supernova ejecta.