SN 2020kyg and the rates of faint Iax supernovae from ATLAS

Research output: Contribution to journalJournal articleResearchpeer-review

Documents

  • stac177

    Final published version, 4.27 MB, PDF document

  • Shubham Srivastav
  • S. J. Smartt
  • M. E. Huber
  • K. C. Chambers
  • Angus, Charlotte
  • T-W Chen
  • F. P. Callan
  • J. H. Gillanders
  • O. R. McBrien
  • S. A. Sim
  • M. Fulton
  • Hjorth, Jens
  • K. W. Smith
  • D. R. Young
  • K. Auchettl
  • J. P. Anderson
  • G. Pignata
  • T. J. L. de Boer
  • C-C Lin
  • E. A. Magnier

We present multiwavelength follow-up observations of the ATLAS discovered faint Iax supernova SN 2020kyg that peaked at an absolute magnitude of M-g approximate to -14.9 +/- 0.2, making it another member of the faint Iax supernova population. The bolometric light curve requires only approximate to 7 x 10(-3) M-circle dot of radioactive Ni-56, with an ejected mass of M-ej similar to 0.4 M-circle dot and a low kinetic energy of E approximate to 0.05 +/- 0.02 x 10(51) erg. We construct a homogeneous volume-limited sample of 902 transients observed by ATLAS within 100 Mpc during a 3.5 yr span. Using this sample, we constrain the rates of faint Iax (M-r greater than or similar to -16) events within 60 Mpc at 12(-8)(+1)(4) per cent of the SN Ia rate. The overall Iax rate, at 15(-9)(+)(17) per cent of the Ia rate, is dominated by the low-luminosity events, with luminous SNe Iax (M-r less than or similar to -17.5) like 2002cx and 2005hk, accounting for only 0.9(-0.5)(+1.1) per cent of the Ia rate (a 2 sigma upper limit of approximately 3 per cent). We favour the hybrid CONe WD + He star progenitor channel involving a failed deflagration of a near Chandrasekhar mass white dwarf, expected to leave a bound remnant and a surviving secondary companion, as a candidate explanation for faint Iax explosions. This scenario requires short delay times, consistent with the observed environments of SNe Iax. Furthermore, binary population synthesis calculations have suggested rates of 1-18 per cent of the SN Ia rate for this channel, consistent with our rate estimates.

Original languageEnglish
JournalMonthly Notices of the Royal Astronomical Society
Volume511
Issue number2
Pages (from-to)2708-2731
Number of pages24
ISSN0035-8711
DOIs
Publication statusPublished - 15 Feb 2022

    Research areas

  • supernovae: general, supernovae: individual: SN 2020kyg, NEAR-INFRARED OBSERVATIONS, EXTREMELY LOW-LUMINOSITY, LATE-TIME SPECTROSCOPY, WHITE-DWARF, GAIA DR2, REDSHIFT, I., EVOLUTION, TRANSIENT, 2005HK

ID: 302384675