The White Dwarf-neutron Star Binary Model of Repeating FRBs

Fast Radio Bursts (FRBs) are transient and bright radio pulses from cosmological origins, which have two types: repeating FRBs and non-repeating FRBs. A compact binary system composed of a neutron star with a strong bipolar magnetic field and a magnetic white dwarf may be able to explain the repeated behavior of repeating FRBs. When the white dwarf fills its Roche lobe, mass transfer will occur through the inner Lagrange point to the surface of the neutron star. After an explosion, the white dwarf may be kicked away, and accreted again in the evolution process to realize the phenomenon of repeated explosion. Based on the observation data of repeating FRBs 121102 and 180916, we studied the relationship between the time interval of two adjacent bursts and the fluence of the subsequent burst in the neutron star-white dwarf binary model. By comparing the theoretical values with the observed values, we confirmed that such an intermittent outflow mechanism of Roche lobe may explain the repeated behavior of repeating FRBs.