Decaying neutrino and a high cosmological baryon density

The low second acoustic peak in the recent Boomerang data may indicate a cosmological baryon density which is larger than allowed by standard big bang nucleosynthesis. We show that the decay of the tau-neutrino: ντ→νe+φ, where νe is the electron neutrino and φ is a scalar, essentially can assure agreement between BBN calculations and light element observations for a large baryon density.