SN 2024bfu, SN 2025qe, and the early light curves of type Iax supernovae
arXiv:2506.02118 · doi:10.1093/mnras/staf1675
Abstract
Type Iax supernovae (SNe Iax) are one of the most common subclasses of thermonuclear supernova and yet their sample size, particularly those observed shortly after explosion, remains relatively small. In this paper we present photometric and spectroscopic observations of two SNe Iax discovered shortly after explosion, SN 2024bfu and SN 2025qe. Both SNe were observed by multiple all-sky surveys, enabling tight constraints on the moment of first light and the shape of the early light curve. Our observations of SN 2025qe begin <2d after the estimated time of first light and represent some of the earliest observations of any SN Iax. Spectra show features consistent with carbon absorption throughout the evolution of SN 2025qe, potentially indicating the presence of unburned material throughout the ejecta. We gather a sample of SNe Iax observed by ATLAS, GOTO, and ZTF shortly after explosion and measure their rise times and early light curve power-law rise indices. We compare our results to a sample of normal SNe Ia and find indications that SNe Iax show systematically shorter rise times, consistent with previous work. We also find some indication that SNe Iax show systematically lower rise indices than normal SNe Ia. The low rise indices observed among SNe Iax are qualitatively consistent with extended Ni distributions and more thoroughly-mixed ejecta compared to normal SNe Ia, similar to predictions from pure deflagration explosions.
26 pages, 4 appendices, 20 figures, 10 tables. Accepted by MNRAS
References in corpus (35)
- The Zwicky Transient Facility: System Overview, Performance, and First Results
- The Zwicky Transient Facility: Data Processing, Products, and Archive
- Determining the Type, Redshift, and Age of a Supernova Spectrum
- PESSTO : survey description and products from the first data release by the Public ESO Spectroscopic Survey of Transient Objects
- Design and operation of the ATLAS Transient Science Server
- The Spectroscopic Diversity of Type Ia Supernovae
- Secondary Maximum in the Near-Infrared Lightcurves of Type Ia Supernovae
- The Peculiar SN 2005hk: Do Some Type Ia Supernovae Explode as Deflagrations?
- Late-Time Spectroscopy of SN 2002cx: The Prototype of a New Subclass of Type Ia Supernovae
- Type Ia Supernova Explosions in Binary Systems: A Review
- Deflagrations in hybrid CONe white dwarfs: a route to explain the faint Type Iax supernova 2008ha
- The Rising Light Curves of Type Ia Supernovae
- Comprehensive Observations of the Bright and Energetic Type Iax SN 2012Z: Interpretation as a Chandrasekhar Mass White Dwarf Explosion
- ESC observations of SN 2005cf. I. Photometric Evolution of a Normal Type Ia Supernova
- The evolution of the peculiar Type Ia supernova SN 2005hk over 400 days
- Spectropolarimetry of the Peculiar Type Ia SN 2005hk
- Gaia Data Release 3: The Galaxy in your preferred colours. Synthetic photometry from Gaia low-resolution spectra
- Early light curves for Type Ia supernova explosion models
- Supernovae and their host galaxies. I. The SDSS DR8 database and statistics
- Wait for it: Post-supernova winds driven by delayed radioactive decays
- Determining the Ni distribution of type Ia supernovae from observations within days of explosion
- Early observations of the nearby type Ia supernova SN 2015F
- The birth rate of SNe Ia from hybrid CONe white dwarfs
- The lowest of the low: discovery of SN 2019gsc and the nature of faint Iax supernovae
- SN 2019muj -- a well-observed Type Iax supernova that bridges the luminosity gap of the class
- SN 2020kyg and the rates of faint Iax Supernovae from ATLAS
- Detecting the signatures of helium in type Iax supernovae
- Models of pulsationally assisted gravitationally confined detonations with different ignition conditions
- Observations of the low-luminosity Type Iax supernova 2019gsc: a fainter clone of SN 2008ha?
- Intermediate Luminosity Type Iax SN 2019muj With Narrow Absorption Lines: Long-Lasting Radiation Associated With a Possible Bound Remnant Predicted by the Weak Deflagration Model
- Early and Extensive Ultraviolet Through Near Infrared Observations of the Intermediate-Luminosity Type Iax Supernovae 2024pxl
- An analysis of the spectroscopic signatures of layering in the ejecta of type Iax supernovae
- White dwarf deflagrations for Type Iax supernovae: Polarisation signatures from the explosion and companion interaction
- SN 2020udy: a SN Iax with strict limits on interaction consistent with a helium-star companion
- Including a Luminous Central Remnant in Radiative Transfer Simulations for Type Iax Supernovae