Abstract
We report initial observations and analysis on the Type IIb SN 2016gkg in the nearby galaxy NGC 613. SN 2016gkg exhibited a clear double-peaked light curve during its early evolution, as evidenced by our intensive photometric follow-up campaign. SN 2016gkg shows strong similarities with other Type IIb SNe, in particular, with respect to the He i emission features observed in both the optical and near-infrared. SN 2016gkg evolved faster than the prototypical Type IIb SN 1993J, with a decline similar to that of SN 2011dh after the first peak. The analysis of archival Hubble Space Telescope images indicate a pre-explosion source at SN 2016gkg's position, suggesting a progenitor star with a ∼mid-F spectral type and initial mass 15-20 Ṁ, depending on the distance modulus adopted for NGC 613. Modeling the temperature evolution within of explosion, we obtain a progenitor radius of R, smaller than that obtained from the analysis of the pre-explosion images (240-320 R ).
Original language | English |
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Article number | L12 |
Number of pages | 7 |
Journal | Astrophysical Journal Letters |
Volume | 836 |
Issue number | 1 |
DOIs | |
State | Published - 10 Feb 2017 |
Keywords
- supernovae: general
- supernovae: individual (2016gkg)
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science