Type Ib supernova Master OT J120451.50+265946.6: radio emitting shock with inhomogeneities crossing through a dense shell

We present radio observations of a Type Ib supernova (SN) Master OT J120451.50+265946.6. Our low frequency Giant Metrewave Radio Telescope (GMRT) data taken when the SN was in the optically thick phase for observed frequencies reveal inhomogeneities in the structure of the radio emitting region. The high frequency Karl G. Jansky Very Large Array data indicate that the shock is crossing through a dense shell between $\sim$ 47 to $\sim 87$ days. The data $\ge 100$ days onwards are reasonably well fit with the inhomogeneous synchrotron-self absorption model. Our model predicts that the inhomogeneities should smooth out at late times. Low frequency GMRT observations at late epochs will test this prediction. Our findings suggest the importance of obtaining well-sampled wide band radio data in order to understand the intricate nature of the radio emission from young supernovae.