Chasing X-ray counterparts to Fast Radio Bursts and Hypernebula with AXIS (Navin Sridhar)

Fast Radio Bursts are a new class of ms-duration coherent radio flashes, mostly of extragalactic origin. In April 2020, an FRB was detected from a Galactic magnetar, contemporaneous with a brief X-ray flash. A couple of years later, the same source produced an FRB contemporaneous with the largest spin glitch seen in a magnetar---as monitored from the quasi-periodic X-ray bursts. These observations established that at least some of the FRBs may be produced by young magnetars and can be accompanied by high-energy X-ray counterparts. However, recent observations have hinted towards multiple progenitors of FRBs, including a much older stellar population, such as accreting X-ray binaries. Some FRBs are also associated with a persistent radio counterpart (e.g., magnetar wind nebula or a hypernebula), albeit without any detections of a persistent high-energy counterpart. I will talk about how AXIS can play a role in constraining the properties of the FRB engine from their expected X-ray emissions.