2021ApJ...923...32B

The study of stripped-envelope core-collapse supernovae (SNe), with evidence for strong interaction of SN ejecta with the circumstellar medium (CSM), provides insights into the pre-supernova progenitor, and a fast-forwarded view of the progenitor mass-loss history. In this context, we present late-time radio observations of SN 2004dk, a Type Ibc supernova located in the galaxy NGC 6118, at a distance of d_L ≃ 23 Mpc. About 10 yr after explosion, SN 2004dk has shown evidence for Hα emission, possibly linked to the SN ejecta interacting with a H-rich CSM. Using data from the VLA Low Band Ionosphere and Transient Experiment (VLITE), we confirm the presence of a late-time radio rebrightening accompanying the observed Hα emission. We model the SN 2004dk radio light curves within the (spherically symmetric) synchrotron-self-absorption (SSA) model. Within this model, our VLITE observations combined with previously collected VLA data favor an interpretation of SN 2004dk as a strongly CSM-interacting radio SN going through a complex environment shaped by nonsteady mass loss from the SN progenitor.