Detecting the signatures of helium in type Iax supernovae

Abstract

Recent studies have argued that the progenitor system of type Iax supernovae must consist of a carbon-oxygen white dwarf accreting from a helium star companion. Based on existing explosion models invoking the pure deflagration of carbon-oxygen white dwarfs, we investigate the likelihood of producing spectral features due to helium in type Iax supernovae. From this scenario, we select those explosion models producing ejecta and ${}^{56}$Ni masses that are broadly consistent with those estimated for type Iax supernovae (0.014 - 0.478~$M_{\odot }$ and $\sim 0.003$ - 0.183~$M_{\odot }$, respectively). To this end, we present a series of models of varying luminosities ($-18.4\lesssim M_{\mathrm{V}}\lesssim -14.5$~mag) with helium abundances accounting for up to $\sim$36\% of the ejecta mass, and covering a range of epochs beginning a few days before B$-$band maximum to approximately two weeks after maximum. We find that the best opportunity for detecting \ion{He}{i} features is at near-infrared wavelengths, and in the post-maximum spectra of the fainter members of this class. We show that the optical spectrum of SN~2007J is potentially consistent with a large helium content (a few 10${}^{-2}{M}_{\odot }$), but argue that current models of accretion and material stripping from a companion struggle to produce compatible scenarios. We also investigate the presence of helium in all objects with near-infrared spectra. We show that SNe~2005hk, 2012Z, and 2015H contain either no helium or their helium abundances are constrained to much lower values ($\lesssim$10${}^{-3}{M}_{\odot }$). Our results demonstrate the differences in helium content among type Iax supernovae, perhaps pointing to different progenitor channels. Either SN~2007J is an outlier in terms of its progenitor system, or it is not a true member of the type Iax supernova class.

15 pages, 12 figures, 2 tables. Accepted for publication in Astronomy and Astrophysics

References in corpus (17)

• Faint Thermonuclear Supernovae from AM Canum Venaticorum Binaries
• The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations?
• Late-Time Spectroscopy of SN 2002cx: The Prototype of a New Subclass of Type Ia Supernovae
• Unstable Helium Shell Burning on Accreting White Dwarfs
• Deflagrations in hybrid CONe white dwarfs: a route to explain the faint Type Iax supernova 2008ha
• The impact of type Ia supernovae on main sequence binary companions
• Comprehensive Observations of the Bright and Energetic Type Iax SN 2012Z: Interpretation as a Chandrasekhar Mass White Dwarf Explosion
• Slow-Speed Supernovae from the Palomar Transient Factory: Two Channels
• Possible Detection of the Stellar Donor or Remnant for the Type Iax Supernova 2008ha
• He-accreting carbon-oxygen white dwarfs and type Ia supernovae
• Investigating the diversity of supernovae type Iax: A MUSE and NOT spectroscopic study of their environments
• One-dimensional non-LTE time-dependent radiative transfer of an He-detonation model and the connection to faint and fast-decaying supernovae
• The hybrid CONe WD + He star scenario for the progenitors of type Ia supernovae
• On the Progenitor System of the Type Iax Supernova 2014dt in M61
• Helium in Double-Detonation Models of Type Ia Supernovae
• Constraints on single-degenerate Chandrasekhar mass progenitors of Type Iax supernovae
• Convection Destroys the Core/Mantle Structure in Hybrid C/O/Ne White Dwarfs

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