Interstellar scintillations as a tool for studying the hyperfine radio structure of quasars and galaxy nuclei

Interstellar scintillations can be utilized to investigate the hyperfine (less than or equal to 10 to the -5th arc sec) angular structure of quasars and galaxy nuclei, as well as its evolution with time. The detection of such scintillations is most promising at wavelengths near 3 cm. The expected scintillation index m is approximately equal to 1%, with a time scale of about 3h. Scintillation measurements of compact structures in quasars and galaxy nuclei would be a valuable complement to results obtained by the VLBI method.