Molecular maser radio emission in the environment of young stellar objects (Review)

Abstract

AbstractA brief review of properties of molecular maser sources in star‐forming regions is given. Different types of sources, their structure and variability are discussed. The variability of H2O masers at a timescale of several days observed in the case of the Cep A maser source is difficult to explain in the model of energy diffusion inside a maser cloud. Another possibility is suggested and analysed. An H2O maser flare may be due to amplification of a strong nonthermal radio flare of the magnetically active central young star (possibly, of the T Tauri variability type) by an initially unsaturated H2O maser. An observational test is suggested.