An international team of astronomers has noticed a new eclipsing binary system, represented by an M-dwarf rotating around a main sequence star. The dwarf differs in that it demonstrates a relativistic radiant effect.
This effect is also called Doppler amplification — a process where relativistic effects change the apparent luminosity of a radiating substance moving at a speed close to the speed of light. The process is caused by the reflex movement of stars, which makes changes in the photometric flow due to the Doppler effect.
Astronomers are interested in measuring the radiant effect, especially in binary systems, because it will allow an independent assessment of the radial velocity of the second component. The indicator is able to play a decisive role in the disclosure of physical parameters and the characteristics of such systems.
The phase folded light curve and the best model for EPIC 219654213. Gray dots - measurements, black - circular data. The solid line is the best model
Using data from the Kepler spacecraft (mission K2), scientists were able to study the star EPIC 219654213, which was originally identified as the master of the planetary system. But the K2 data with additional spectroscopic surveys showed that we have a double star. The main component is a star of the main sequence of the spectral type F7V. By age, it reached 4.1 billion years, by its mass it almost converges with solar, and the radius is 1.52 solar. The satellite is a dwarf of the spectral type M5V, which is 5 times smaller than the Sun in massiveness and size. It is located almost in a circular orbit around the main star, flying over 5.44 days with a distance of 0.065 a. e.
The analysis also showed changes in the amplitude of the radiant effect of 35 ppm, which accounts for 50% of the apparent discrepancy between the expected and the observed effect of the radiance. The researchers plan to explore EPIC 219654213 using exoplanet hunting missions like TESS and PLATO. Further reviews will help confirm the true nature of the M-dwarf, which may also be a brown dwarf or a hot Jupiter.
