A possible origin of the overlapping light-curve of eRO–QPE1

ABSTRACT Quasi-periodic eruptions (QPEs) are recurrent X-ray eruptions found so far in the nuclei of low-mass galaxies. Their trigger mechanism is still unknown, and new observations are demanded to reveal the physics behind it. Recently, chaotic mixtures of multiple overlapping eruptions with varying amplitudes have been observed in eRO–QPE1 obs1. This complex behaviour presents a challenge to the existing QPE models. In this paper, we propose that the overlapping features may be the result of gravitational lensing. Therefore, all QPEs could share a common trigger mechanism, and we do not need a special mechanism for eRO–QPE1.