The luminous type Ia supernova 2022ilv and its early excess emission

Abstract

We present observations and analysis of the host-less and luminous type Ia supernova 2022ilv, illustrating it is part of the 2003fg-like family, often referred to as super-Chandrasekhar (Ia-SC) explosions. The ATLAS light curve shows evidence of a short-lived, pulse-like early excess, similar to that detected in another luminous type Ia supernova (SN 2020hvf). The light curve is broad and the early spectra are remarkably similar to SN 2009dc. Adopting a redshift of $z=0.026\pm 0.005$ for SN 2022ilv based on spectral matching, our model light curve requires a large ${}^{56}$Ni mass in the range $0.7-1.5$ M${}_{\odot }$, and a large ejecta mass in the range $1.6-2.3$ M${}_{\odot }$. The early excess can be explained by fast-moving SN ejecta interacting with a thin, dense shell of circumstellar material close to the progenitor ($\sim 10^{13}$ cm), a few hours after the explosion. This may be realised in a double-degenerate scenario, wherein a white dwarf merger is preceded by ejection of a small amount ($\sim 10^{-3}-10^{-2}$ M${}_{\odot }$) of hydrogen and helium-poor tidally stripped material. A deep pre-explosion Pan-STARRS1 stack indicates no host galaxy to a limiting magnitude of $r\sim 24.5$. This implies a surprisingly faint limit for any host of $M_r\gtrsim -11$, providing further evidence that these types of explosion occur predominantly in low-metallicity environments.

arXiv commentAccepted to ApJL after minor revision

References in corpus (45)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• The Zwicky Transient Facility: System Overview, Performance, and First Results
• The Swift Ultra-Violet/Optical Telescope
• Overview of the DESI Legacy Imaging Surveys
• ATLAS: A High-Cadence All-Sky Survey System
• Observational clues to the progenitors of Type-Ia supernovae
• WISeREP - An Interactive Supernova Data Repository
• The SDSS View of the Palomar-Green Bright Quasar Survey
• The type Ia supernova SNLS-03D3bb from a super-Chandrasekhar-mass white dwarf star
• Determining the Type, Redshift, and Age of a Supernova Spectrum
• Seeing the Collision of a Supernova with its Companion Star
• Nearby Supernova Factory Observations of SN 2007if: First Total Mass Measurement of a Super-Chandrasekhar-Mass Progenitor
• Design and operation of the ATLAS Transient Science Server
• A Circumbinary Disk in the Final Stages of Common Envelope and the Core-Degenerate Scenario for Type Ia Supernovae
• The ATLAS All-Sky Stellar Reference Catalog
• The Luminous and Carbon-Rich Supernova 2006gz: A Double Degenerate Merger?
• Remnant evolution after a carbon-oxygen white dwarf merger
• The Broad-lined Type Ic SN 2003jd
• Fourteen Months of Observations of the Possible Super-Chandrasekhar Mass Type Ia Supernova 2009dc
• High luminosity, slow ejecta and persistent carbon lines: SN 2009dc challenges thermonuclear explosion scenarios
• Ultraviolet Light Curves of Supernovae with Swift Uvot
• Observational Predictions for Sub-Chandrasekhar Mass Explosions: Further Evidence for Multiple Progenitor Systems for Type Ia Supernovae
• The structure and fate of white dwarf merger remnants
• The Pan-STARRS Data Processing System
• The Extremes of Thermonuclear Supernovae
• The Rising Light Curves of Type Ia Supernovae
• Exploring the Potential Diversity of Early Type Ia Supernova Light Curves
• Type Ia Supernovae from Merging White Dwarfs I. Prompt Detonations
• Tidal Tail Ejection as a Signature of Type~Ia Supernovae from White Dwarf Mergers
• Hunting for Supermassive Black Holes in Nearby Galaxies with the Hobby-Eberly Telescope
• Seeing Double: ASASSN-18bt Exhibits a Two-Component Rise in the Early-Time K2 Light Curve
• 'Super-Chandrasekhar' Type Ia Supernovae at nebular epochs
• Surface Radioactivity or Interactions? Multiple Origins of Early-excess Type Ia Supernovae and Associated Subclasses
• Spectral modelling of the "Super-Chandra" Type Ia SN 2009dc - testing a 2 M_sun white dwarf explosion model and alternatives
• Determining the ${}^{56}$Ni distribution of type Ia supernovae from observations within days of explosion
• Discovery of the Fastest Early Optical Emission from Overluminous SN Ia 2020hvf: A Thermonuclear Explosion within a Dense Circumstellar Environment
• Carnegie Supernova Project: The First Homogeneous Sample of "Super-Chandrasekhar Mass"/2003fg-like Type Ia Supernova
• Type Ia supernovae within dense carbon-oxygen rich envelopes: a model for 'Super-Chandrasekhar' explosions?
• Constraining Type Ia supernova explosions and early flux excesses with the Zwicky Transient Factory
• A Carbon/Oxygen-dominated Atmosphere Days After Explosion for the "Super-Chandrasekhar" Type Ia SN 2020esm
• ASASSN-15hy: an under-luminous, red 03fg-like type Ia supernova
• Early UV emission from disk-originated matter (DOM) in type Ia supernovae in the double degenerate scenario
• SN 2012dn from early to late times: 09dc-like supernovae reassessed
• ASASSN-15pz: Revealing Significant Photometric Diversity among 2009dc-like, Peculiar SNe Ia

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• A thermonuclear supernova interacting with hydrogen- and helium-deficient circumstellar material. SN 2020aeuh as a SN Ia-CSM-C/O?
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