Repeating FRB 121102 : Eight-year Fermi-LAT Upper Limits and Implications

Understand

The repeating fast radio burst (FRB) source that produced FRB 121102 was recently localized in a star forming galaxy at $z=0.193$, which is associated with an extended radio source at the burst location.

• One possibility is that the repeating FRBs are produced by a new-born magnetar, which also powers the radio nebula.
• If so, the magnetar may produce $\gamma$-ray emission due to magnetic dipolar spin-down.
• The luminosity depends on the magnetar spin parameters and age.