Direct evidence of two-component ejecta in supernova 2016gkg from nebular spectroscopy

Hanindyo Kuncarayakti, Gaston Folatelli, Keiichi Maeda +17

Spectral observations of the type-IIb supernova (SN) 2016gkg at 300-800 days are reported. The spectra show nebular characteristics, revealing emission from the progenitor star's m…