Nebular H α emission in Type Ia supernova 2016jae
There is a wide consensus that Type Ia supernovae (SNe Ia) originate from the thermonuclear explosion of CO white dwarfs (WDs), with the lack of hydrogen in the observed spectra as a distinctive feature. Here, we present supernova (SN) 2016jae, which was classified as an SN Ia from a spectrum obtain...
| Autores: | , , , , , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2021 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/260981 |
| Acceso en línea: | http://hdl.handle.net/10261/260981 |
| Access Level: | acceso abierto |
| Palabra clave: | Supernovae: general Supernovae: individual: SN2016jae Supernovae: individual: SN2018cqj Supernovae: individual |
| Sumario: | There is a wide consensus that Type Ia supernovae (SNe Ia) originate from the thermonuclear explosion of CO white dwarfs (WDs), with the lack of hydrogen in the observed spectra as a distinctive feature. Here, we present supernova (SN) 2016jae, which was classified as an SN Ia from a spectrum obtained soon after its discovery. The SN reached a B-band peak of o17.93 0.34 mag, followed by a fast luminosity decline with sBV0:56 0:06 and inferred m15(B) of 1:88 0:10 mag. Overall, the SN appears to be a 'transitional' event between a 'normal' SN Ia and a very dim SN Ia, such as 91bg-like SNe. Its peculiarity is that two late-time spectra, taken at +84 and +142 days after the peak, show a narrow line of H (with full width at half maximum of 650 and 1000 km so1, respectively). This is the third low-luminosity and fast-declining SN Ia, after SN2018cqj/ATLAS18qtd and SN2018fhw/ASASSN-18tb, found in the 100IAS survey to show a resolved narrow H line in emission in its nebular-phase spectra. We argue that the nebular H emission originates in an expanding hydrogen-rich shell (with velocity 1000 km so1). The hydrogen shell velocity is too high to be produced during a common envelope phase, though it may be consistent with some material stripped from an H-rich companion star in a single-degenerate progenitor system. However, the derived mass of this stripped hydrogen is 0.002-0.003 M , which is much less than that expected (>0.1 M ) from standard models for these scenarios. Another plausible sequence of events is a weak SN ejecta interaction with an H shell ejected by optically thick winds or a nova-like eruption on the CO WD progenitor some years before the SN explosion.© ESO 2021. |
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