Speaker
Description
Supernovae explosions are among the most powerful and brightest events in the universe, marking the end of the star’s life. These events although having been studied widely in optical and x-ray windows, radio observations offer a unique opportunity especially when the event happens within a dense environment. The radio emissions detected are produced through the synchrotron radiation mechanism, where relativistic electrons spiral around the magnetic field lines causing emission of radiation across a broad spectrum. By analyzing the radio flux intensities at a given frequency against time yields a radio light curve. The radio light curve exhibit a predictable pattern; an initial rise, followed by a peak (turning point) and then a gradual decline as the energy dissipates as the shock sweeps into lower-density circumstellar medium (CSM). However, there is a growing number of observed radio light curves that deviates from this evolution trend by having a re-brightening at a later-date after the explosion. I will be sharing the results of re-modelling the re-brightening part of the radio light curve to reconstruct the progenitor mass-loss histories, characterize the CSM density and geometry and also constrain the shock microphysics during the interaction. The findings are crucial in constructing accurate stellar evolution models, particularly for massive stars, whose final stages are still poorly constrained observationally.
| Stream | Science or Engineering |
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