The Whisper of a Whimper of a Bang: 2400 Days of the Type Ia SN 2011fe Reveals the Decay of ${}^{55}$Fe

Abstract

We analyze new multi-filter Hubble Space Telescope (HST) photometry of the normal Type Ia supernova (SN Ia) 2011fe out to $\approx 2400$days after maximum light, the latest observations to-date of a SN Ia. We model the pseudo-bolometric light curve with a simple radioactive decay model and find energy input from both ${}^{57}$Co and ${}^{55}$Fe are needed to power the late-time luminosity. This is the first detection of ${}^{55}$Fe in a SN Ia. We consider potential sources of contamination such as a surviving companion star or delaying the deposition timescale for ${}^{56}$Co positrons but these scenarios are ultimately disfavored. The relative isotopic abundances place direct constraints on the burning conditions experienced by the white dwarf (WD). Additionally, we place a conservative upper limit of $<10^{-3}{M}_{\odot }$ on the synthesized mass of ${}^{44}$Ti. Only 2 classes of explosion models are currently consistent with all observations of SN2011fe: 1) the delayed detonation of a low-${\rho }_c$, near-${\mathrm{M}}_{\mathrm{Ch}}$ ($1.2-1.3M_{\odot }$) WD, or 2) a sub-${\mathrm{M}}_{\mathrm{Ch}}$ ($1.0-1.1M_{\odot }$) WD experiencing a thin-shell double detonation.

14 pages, 8 figures, 1 table. MNRAS, accepted

References in corpus (45)

• The Zwicky Transient Facility: System Overview, Performance, and First Results
• Double-detonation sub-Chandrasekhar supernovae: can minimum helium shell masses detonate the core?
• Double-detonation supernovae of sub-Chandrasekhar mass white dwarfs
• Constraining the Type Ia Supernova Progenitor: The Search for Hydrogen in Nebular Spectra
• Early Blue Excess from the Type Ia Supernova 2017cbv and Implications for Its Progenitor
• Deflagrations in hybrid CONe white dwarfs: a route to explain the faint Type Iax supernova 2008ha
• No X-rays from the very nearby Type Ia SN2014J: constraints on its environment
• Evidence for sub-Chandrasekhar-mass progenitors of Type Ia supernovae at the faint end of the width-luminosity relation
• Nebular spectra and abundance tomography of the type Ia supernova SN 2011fe: a normal SN Ia with a stable Fe core
• Double Detonations with Thin, Modestly Enriched Helium Layers Can Make Normal Type Ia Supernovae
• The Tip of the Red Giant Branch Distances to Type Ia Supernova Host Galaxies. IV. Color Dependence and Zero-Point Calibration
• Light and color curve properties of type Ia supernovae: Theory vs. Observations
• Flame Evolution During Type Ia Supernovae and the Deflagration Phase in the Gravitationally Confined Detonation Scenario
• The light curve of SN 1987A revisited: constraining production masses of radioactive nuclides
• Double detonations of sub-Chandrasekhar mass CO white dwarfs: Can different core and He shell masses explain variations of Type Ia supernovae?
• No trace of a single-degenerate companion in late spectra of SNe 2011fe and 2014J
• Non-Local Thermodynamic Equilibrium Radiative Transfer Simulations of Sub-Chandrasekhar-Mass White Dwarf Detonations
• SNe Ia from double detonations: Impact of core-shell mixing on the carbon ignition mechanism
• Nebular-Phase Spectra of Nearby Type Ia Supernovae
• Detonating Failed Deflagration Model of Thermonuclear Supernovae I. Explosion Dynamics
• Sub-Chandrasekhar progenitors favoured for type Ia supernovae: Evidence from late-time spectroscopy
• Swift X-Ray Upper Limits on Type Ia Supernova Environments
• Progenitor constraints on the Type-Ia supernova SN2011fe from pre-explosion Hubble Space Telescope HeII narrow-band observations
• Evidence for Sub-Chandrasekhar Mass Type Ia Supernovae from an Extensive Survey of Radiative Transfer Models
• The white dwarf's carbon fraction as a secondary parameter of Type Ia supernovae
• Late-time near-infrared observations of SN 2005df
• Spectroscopy of the Type Ia supernova 2011fe past 1000 days
• Late-time emission of type Ia supernovae: optical and near-infrared observations of SN 2001el
• Extremely late photometry of SN~2011fe
• Very late photometry of SN 2011fe
• No hot and luminous progenitor for Tycho's supernova
• Herschel limits on far-infrared emission from circumstellar dust around nearby Type Ia supernovae
• 5.9 keV Mn K-shell X-ray luminosity from the decay of 55Fe in Type Ia supernova models
• Spectral signatures of H-rich material stripped from a non-degenerate companion by a Type Ia supernova
• Constraining magnetic field amplification in SN shocks using radio observations of SNe 2011fe and 2014J
• Excluding super-soft X-ray sources as progenitors for four Type Ia supernovae in the Large Magellanic Cloud
• A Rapid Ionization Change in the Nebular-Phase Spectra of the Type Ia SN 2011fe
• The intermediate nebular phase of SN 2014J: onset of clumping as the source of recombination
• Pre-explosive accretion and simmering phases of Type Ia Supernovae
• Constraints on the density distribution of type Ia supernovae ejecta inferred from late-time light-curve flattening
• Thirty Years of Radio Observations of Type Ia SN 1972E and SN 1895B: Constraints on Circumstellar Shells
• Optical and ultraviolet spectroscopic analysis of SN 2011fe at late times
• Multi-epoch Spectropolarimetry of SN 2011fe
• Tumbling Dice: Radio Constraints on the Presence of Circumstellar Shells around Type Ia Supernovae with Impact Near Maximum Light
• The accuracy of post-processing nucleosynthesis

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