Spectroscopy of the Type Ic Supernova SN 2017iuk Associated with Low-redshift GRB 171205A

Abstract

We here report a spectroscopic monitor for the supernova (SN) SN 2017iuk associated with the long-duration low-luminosity gamma-ray burst (GRB) GRB 171205A at a redshift of 0.037, which is up to now the third GRB–SN event away from us. Our spectroscopic observations and spectral analysis allow us to identify SN 2017iuk as a typical broad-line Type Ic SN. A comparison study suggests that the Type IcBL SN 2017iuk resembles SN 2006aj in the following aspects: (1) similar spectra at the nearby epochs, (2) comparable evolution of the photospheric velocity obtained from the measurements based on both the Si ii λ 6355 line and spectral modeling, and (3) comparable explosion parameters. This analogy could imply the formation of a neutron star in the core collapse of GRB 171205A/SN 2017iuk as previously suggested in GRB 060218/SN 2006aj. The properties of the host galaxy are discussed, which suggest that GRB 171205A/SN 2017iuk occurred in an early-type (S0), high-mass, star-forming galaxy with low specific star formation rate and solar metallicity.