Periodical Component Found in the Space Maser Signal and Its Interpretation

In this paper we report of the periodic component found recently in the signal of the space radio source Sep A. The background for the search was the prediction of the theory of the optic-metrical parametric resonance (OMPR). It suggests that if certain conditions are fulfilled, the action of the periodic source of the gravitational waves (GW) like a compact binary or a pulsar on a monochromatic electromagnetic wave of a space maser would cause the special type of a parametric resonance, and a specific component would appear in the observed maser signal. This effect has a resonance character, therefore, it is of the zeroth order in the dimensionless amplitude of the GW. This makes it principally different from all the 18 other known effects that could be used for the detection of the GW - all of them are of the first order in the extremely small amplitude of the GW. The periodic change of the intensity of one of the spectum components is hard to explain by any other mechanism than OMPR. If such observations performed independently give similar results, they would provide another evidence of the GW existence and the perspectives of the GW astronomy could be discussed.