Published online by Cambridge University Press: 12 April 2016
Negative preflares (NPFs) of UV Cet stars, which were first observed by Italian astronomers |1|, are a highly unusual type of preflare activity without direct analogy in solar flares. The rarity of these events in the visual region leads to difficulties in statistical investigations. At present one can consider as reliably established only that the mean NPF-amplitudes increase and the probability of their appearance decreases with a shift toward blue |2|. According to |3| NPFs are observed mainly before flares of smaller amplitudes. Beginning in 1974 at the Crimea and the Astronomical Institute of Tashkent a series of works on the theory and observation of NPFs was carried out. A short review of these is given below.