2021ApJ...920...34Y

Fast radio bursts (FRBs) are bright radio transients with short durations and extremely high brightness temperatures, and their physical origins are still unknown. Recently, a repeating source, FRB 20200120E, was found in a globular cluster in the very nearby M81 galaxy. The associated globular cluster has an age of ∼9.13 Gyr, and hosts an old population of stars. In this work, we consider that an FRB source is in a close binary system with a low-mass main-sequence star as its companion. Due to the large burst energy of the FRB, when the companion star stops the FRB, its surface would be heated by the radiation-induced shock, and make reemission. For a binary system with a solar-like companion star and an orbital period of a few days, we find that the reemission is mainly at an optical band, with delays of a few seconds after the FRB. Its luminosity is several times larger than the solar luminosity, and the duration is about hundreds of seconds. Such a transient might be observable in a future multiwavelength follow-up observation for Galactic FRB sources.