2025MNRAS.541.3214E

Transition radiation is produced when a relativistic charged particle enters or leaves a solid medium. The electrons that produce synchrotron radiation may interact with the dust in circumstellar environments, leading to the emission of transition radiation. We explore the production of transition radiation in dusty novae that also display synchrotron radiation emission. Transition radiation is emitted in the hard ultraviolet/X-ray range. We suggest that, even when the transition radiation is not itself directly observable, it may have a role in determining the ionisation balance of, and grain heating in, nova ejecta. Furthermore, it may be important in other dusty environments (such as supernova remnants) with non-thermal radio emission.