Modelling the early time behaviour of type Ia supernovae: effects of the 56Ni distribution

M. R. Magee, S. A. Sim, R. Kotak, W. E. Kerzendorf

Research output: Contribution to journalArticlepeer-review

28 Citations (Scopus)
214 Downloads (Pure)


Recent studies have demonstrated the diversity in type Ia supernovae (SNe Ia) at early times and highlighted a need for a better understanding of the explosion physics as manifested by observations soon after explosion. To this end, we present a Monte Carlo code designed to model the light curves of radioactively driven, hydrogen-free transients from explosion to approximately maximum light. In this initial study, we have used a parametrised description of the ejecta in SNe Ia, and performed a parameter study of the effects of the $^{56}$Ni distribution on the observed colours and light curves for a fixed $^{56}$Ni mass of 0.6 $M_\odot$. For a given density profile, we find that models with $^{56}$Ni extending throughout the entirety of the ejecta are typically brighter and bluer shortly after explosion. Additionally, the shape of the density profile itself also plays an important role in determining the shape, rise time, and colours of observed light curves. We find that the multi-band light curves of at least one SNe Ia (SN 2009ig) are inconsistent with less extended $^{56}$Ni distributions, but show good agreement with models that incorporate $^{56}$Ni throughout the entire ejecta. We further demonstrate that comparisons with full $UVOIR$ colour light curves are powerful tools in discriminating various $^{56}$Ni distributions, and hence explosion models.
Original languageEnglish
Article numberA115
Number of pages13
JournalAstronomy and Astrophysics
Publication statusPublished - 22 Jun 2018


  • Astrophysics - High Energy Astrophysical Phenomena
  • Astrophysics - Instrumentation and Methods for Astrophysics
  • Astrophysics - Solar and Stellar Astrophysics


Dive into the research topics of 'Modelling the early time behaviour of type Ia supernovae: effects of the 56Ni distribution'. Together they form a unique fingerprint.

Cite this