Influence of aerosol lifetime on the interpretation of nucleation experiments with respect to the first nucleation theorem

Abstract. The SAWNUC (Sulphuric Acid Water NUCleation) microphysical aerosol nucleation model is used to study the effect of reactor walls on the interpretation of nucleation experiments with respect to nucleation theory. This work shows that loss processes, such as wall losses, influence the interpretation of nucleation experiments, especially at low growth rates and short lifetimes of freshly nucleated particles. In these cases the power dependency of the formation rates, determined at a certain particle size, with respect to H₂SO₄ does not correspond to the approximate number of H₂SO₄ molecules in the critical cluster as expected by the first nucleation theorem. Observed ∂log(J)/∂log([H₂SO₄]) therefore can vary widely for identical nucleation conditions but different sink terms.