2013/08/31 by Nathan Smith, Jon C. Mauerhan, Jon Mauerhan +2 · 1 citation
Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Ejecta #Event (particle physics) #Gamma-ray bursts and supernovae #Kinetic energy #Light curve #Luminous blue variable #Pair-instability supernova #Physics #Pulsars and Gravitational Waves Research #Red supergiant #Spectral line #Supergiant #Supernova #astro-ph.HE #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stt2269
Accepted to MNRAS on 2013 Nov 21. 18 pages, 9 figures
arxiv created 2013/11/21 · openalex publication_date 2013/12/24 · arxiv updated 2015/06/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The recent supernova (SN) known as SN 2009ip had dramatic precursor eruptions followed by an even brighter explosion in 2012. Its pre-2012 observations make it the best documented SN progenitor in history, but have fuelled debate about the nature of its 2012 explosion – whether it was a true SN or some type of violent non-terminal event. Both could power shock interaction with circumstellar material (CSM), but only a core-collapse SN provides a self-consistent explanation. The persistent broad emission lines in the spectrum require a relatively large ejecta mass, and a corresponding kinetic energy of at least 1051 erg, while the faint 2012a event is consistent with published models of core-collapse SNe from compact (∼60 R⊙) blue supergiants. The light curves of SN 2009ip and another Type IIn, SN 2010mc, were nearly identical; we demonstrate that their spectra match as well, and that both are standard SNe IIn. Our observations contradict the recent claim that the late-time spectrum of SN 2009ip is returning to its progenitor's luminous blue variable-like state, and we show the that late-time spectra of SN 2009ip closely resemble the spectra of SN 1987A. Moreover, SN 2009ip's changing Hα equivalent width after explosion matches behaviour typically seen in core-collapse SNe IIn. Several key facts about SN 2009ip and SN 2010mc argue strongly in favour of a core-collapse interpretation, and make a non-terminal 1050 erg event implausible. The most straightforward and self-consistent interpretation is that SN 2009ip was an initially faint core-collapse explosion of a blue supergiant that produced about half as much 56Ni as SN 1987A, with most of the peak luminosity from CSM interaction.