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ABSTRACT We present optical photometric and spectroscopic analysis of a Type Iax supernova (SN) 2020rea situated at the brighter luminosity end of Type Iax supernovae (SNe). The light curve decline rate of SN 2020rea is Δm15(g) = 1.31 ± 0.08 mag which is similar to SNe 2012Z and 2005hk. Modelling the pseudo-bolometric light curve with a radiation diffusion model yields a mass of 56Ni of 0.13 ± 0.01 M⊙ and an ejecta mass of 0.77$$^{+0.11}_{-0.21}$$ M⊙. Spectral features of SN 2020rea during the photospheric phase show good resemblance with SN 2012Z. TARDIS modelling of the early spectra of SN 2020rea reveals a dominance of Iron Group Elements (IGEs). The photospheric velocity of the Si ii line around maximum for SN 2020rea is ∼ 6500 km s−1 which is less than the measured velocity of the Fe ii line and indicates significant mixing. The observed physical properties of SN 2020rea match with the predictions of pure deflagration model of a Chandrasekhar mass C–O white dwarf. The metallicity of the host galaxy around the SN region is 12 + log(O/H) = 8.56 ± 0.18 dex which is similar to that of SN 2012Z.
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Observational Properties of a Bright Type lax SN 2018cni and a Faint Type Iax SN 2020kyg
Abstract We present the optical photometric and spectroscopic analysis of two Type Iax supernovae (SNe), 2018cni and 2020kyg. SN 2018cni is a bright Type Iax SN ( M V ,peak = −17.81 ± 0.21 mag), whereas SN 2020kyg ( M V ,peak = −14.52 ± 0.21 mag) is a faint one. We derive 56 Ni mass of 0.07 and 0.002 M ⊙ and ejecta mass of 0.48 and 0.14 M ⊙ for SNe 2018cni and 2020kyg, respectively. A combined study of the bright and faint Type Iax SNe in R / r -band reveals that the brighter objects tend to have a longer rise time. However, the correlation between the peak luminosity and decline rate shows that bright and faint Type Iax SNe exhibit distinct behavior. Comparison with standard deflagration models suggests that SN 2018cni is consistent with the deflagration of a CO white dwarf, whereas the properties of SN 2020kyg can be better explained by the deflagration of a hybrid CONe white dwarf. The spectral features of both the SNe point to the presence of similar chemical species but with different mass fractions. Our spectral modeling indicates stratification at the outer layers and mixed inner ejecta for both of the SNe.
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- Award ID(s):
- 1911225
- PAR ID:
- 10450576
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Date Published:
- Journal Name:
- The Astrophysical Journal
- Volume:
- 953
- Issue:
- 1
- ISSN:
- 0004-637X
- Page Range / eLocation ID:
- 93
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3847/1538-4357/acd559
