Anamaria Gkini: Eruptive mass loss prior to superluminous supernovae

Thursday 31 Oct 2024, 13:15 → 14:00 Europe/Stockholm

A5:1003 (AlbaNova Main Building)

The fate of stars and the type of the resulting supernova (SN) explosions are closely linked to their final years before core collapse. During the late stages of stellar evolution, stars can lose a significant amount of their initial mass through eruptive mass loss, leading to the formation of circumstellar material (CSM) around the SN, which may be observable post-explosion. In this talk, I will focus on superluminous supernovae (SLSNe), a specific type of explosion that is exceptionally bright and cannot be explained by conventional power sources. In particular, I will present two SLSNe that display spectroscopic signatures indicative of line scattering from a rapidly expanding CSM that was ejected shortly before the explosion. First, I will provide a detailed analysis of the photometric properties and evolution of these two SLSNe, placing them in the context of other well-studied SLSNe. Next, I will focus on the modeling of the spectroscopic lines to infer the properties of the CSM and the timing of its ejection. Finally, I will discuss potential mass-loss mechanisms and sources that power these SLSNe.  The discovery of these objects offers valuable insights into the late stages of stellar evolution and enhances our understanding of SLSN progenitors.