Nearby Supernova Factory Observations of SN 2007if: First Total Mass Measurement of a Super-Chandrasekhar-Mass Progenitor
Astrophysical Journal
| dc.creator | Scalzo, R.A | |
| dc.creator | Hoyer, S. | |
| dc.date | 2019-12-18T18:15:03Z | |
| dc.date | 2022-07-07T23:39:32Z | |
| dc.date | 2019-12-18T18:15:03Z | |
| dc.date | 2022-07-07T23:39:32Z | |
| dc.date | 2010 | |
| dc.date.accessioned | 2023-08-22T01:03:00Z | |
| dc.date.available | 2023-08-22T01:03:00Z | |
| dc.identifier | 15010003 | |
| dc.identifier | 15010003 | |
| dc.identifier | https://hdl.handle.net/10533/237223 | |
| dc.identifier.uri | https://repositorioslatinoamericanos.uchile.cl/handle/2250/8303817 | |
| dc.description | We present photometric and spectroscopic observations of SN 2007if, an overluminous (M_V = -20.4), red (B-V = 0.16 at B-band maximum), slow-rising (t_rise = 24 days) type Ia supernova in a very faint (M_g = -14.10) host galaxy. A spectrum at 5 days past B-band maximum light is a direct match to the super-Chandrasekhar-mass candidate SN Ia 2003fg, showing Si II and C II at ~9000 km/s. A high signal-to-noise co-addition of the SN spectral time series reveals no Na I D absorption, suggesting negligible reddening in the host galaxy, and the late-time color evolution has the same slope as the Lira relation for normal SNe Ia. The ejecta appear to be well mixed, with no strong maximum in I-band and a diversity of iron-peak lines appearing in near-maximum-light spectra. SN2007 if also displays a plateau in the Si II velocity extending as late as +10 days, which we interpret as evidence for an overdense shell in the SN ejecta. We calculate the bolometric light curve of the SN and use it and the \ion{Si}{2} velocity evolution to constrain the mass of the shell and the underlying SN ejecta, and demonstrate that SN2007 if is strongly inconsistent with a Chandrasekhar-mass scenario. Within the context of a "tamped detonation" model appropriate for double-degenerate mergers, and assuming no host extinction, we estimate the total mass of the system to be 2.4 +/- 0.2 solar masses, with 1.6 +/- 0.1 solar masses of nickel-56 and with 0.3-0.5 solar masses in the form of an envelope of unburned carbon/oxygen. Our modeling demonstrates that the kinematics of shell entrainment provide a more efficient mechanism than incomplete nuclear burning for producing the low velocities typical of super-Chandrasekhar-mass SNeIa. | |
| dc.description | FONDAP | |
| dc.description | FONDAP | |
| dc.language | eng | |
| dc.relation | instname: Conicyt | |
| dc.relation | reponame: Repositorio Digital RI2.0 | |
| dc.relation | info:eu-repo/grantAgreement/Fondap/15010003 | |
| dc.relation | https://arxiv.org/abs/1003.2217 | |
| dc.rights | Atribución-NoComercial-SinDerivadas 3.0 Chile | |
| dc.rights | http://creativecommons.org/licenses/by-nc-nd/3.0/cl/ | |
| dc.rights | info:eu-repo/semantics/openAccess | |
| dc.title | Nearby Supernova Factory Observations of SN 2007if: First Total Mass Measurement of a Super-Chandrasekhar-Mass Progenitor | |
| dc.title | Astrophysical Journal | |
| dc.type | Articulo | |
| dc.type | info:eu-repo/semantics/article | |
| dc.type | info:eu-repo/semantics/publishedVersion |