SN 2004gt

SN 2004gt was a Type IIn supernova discovered in the galaxy NGC 6946, also known as the Fireworks Galaxy, in 2004. Type IIn supernovae are characterized by their spectra, which exhibit narrow hydrogen emission lines. These narrow lines are thought to arise from the interaction of the supernova ejecta with a dense circumstellar medium (CSM) that was likely expelled from the progenitor star prior to the explosion.

The progenitor star of SN 2004gt is believed to have been a massive star, possibly a Luminous Blue Variable (LBV) or a Wolf-Rayet star. The exact nature of the progenitor is still under investigation. The interaction of the supernova ejecta with the circumstellar material resulted in a bright, long-lasting radio and X-ray emission. Observations of SN 2004gt have contributed to the understanding of the late stages of massive star evolution and the processes that lead to Type IIn supernovae. The light curve of SN 2004gt showed a slow decline, typical of Type IIn supernovae due to the continued interaction with the CSM. Studying this supernova provides insights into the mass-loss mechanisms of massive stars and the composition and structure of the circumstellar environment surrounding these stars before they explode.