Systematic investigation of the effect of 56Ni mixing in the early photospheric velocity evolution of stripped-envelope supernovae

Abstract

Mixing of 56Ni, whose nuclear decay energy is a major luminosity source in stripped-envelope supernovae, is known to affect the observational properties of stripped-envelope supernovae such as light-curve and color evolution. Here we systematically investigate the effect of 56Ni mixing on the photospheric velocity evolution in stripped-envelope supernovae. We show that 56Ni mixing significantly affects the early photospheric velocity evolution. The photospheric velocity, which is often used to constrain the ejecta mass and explosion energy, significantly varies by just changing the degree of 56Ni mixing. In addition, the models with a small degree of 56Ni mixing show a flattening in the early photospheric velocity evolution, while the fully mixed models show a monotonic decrease. The velocity flattening appears in both helium and carbon+oxygen progenitor explosions with a variety of ejecta mass, explosion energy, and 56Ni mass. Some stripped-envelope supernovae with early photospheric velocity information do show such a flattening. We find that Type Ib SN 2007Y, which has early photospheric velocity information, has a signature of a moderate degree of 56Ni mixing in the photospheric velocity evolution and about a half of the ejecta is mixed in it. The immediate spectroscopic follow-up observations of stripped-envelope supernovae shortly after the explosion providing the early photospheric evolution give an important clue to constrain 56Ni mixing in the ejecta.

9 pages, 13 figures, 1 table, accepted by Monthly Notices of the Royal Astronomical Society

References in corpus (10)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• Confined Dense Circumstellar Material Surrounding a Regular Type II Supernova: The Unique Flash-Spectroscopy Event of SN 2013fs
• A Wolf-Rayet-like progenitor of supernova SN 2013cu from spectral observations of a wind
• Theoretical light curves for deflagration models of Type Ia supernova
• Investigating the properties of stripped-envelope supernovae, what are the implications for their progenitors?
• Analysis of Late--time Light Curves of Type IIb, Ib and Ic Supernovae
• Three-Dimensional Explosion Geometry of Stripped-Envelope Core-Collapse Supernovae. II. Modelling of Polarization
• The $\gamma$-ray deposition histories of core-collapse supernovae
• Type Ic Supernova of a 22 ${\text{M}}_{\odot }$ Progenitor

Cited by in corpus (11)

• Low-luminosity type IIP supernovae: SN 2005cs and SN 2020cxd as very low-energy iron core-collapse explosions
• Synthetic observables for electron-capture supernovae and low-mass core collapse supernovae
• The circumstellar material around the Type IIP SN 2021yja
• Progenitor mass constraints for the type Ib intermediate-luminosity SN 2015ap and the highly extinguished SN 2016bau
• Are stripped envelope supernovae really deficient in ${}^{56}$Ni?
• Inferring the progenitor mass-kinetic energy relation of stripped-envelope core-collapse supernovae from nebular spectroscopy
• Velocity evolution of broad-lined type-Ic supernovae with and without gamma-ray bursts
• Optical color of Type Ib and Ic supernovae and implications for their progenitors
• Photospheric velocity evolution of SN 2020bvc: signature of $r$-process nucleosynthesis from a collapsar
• Diagnosing The Ejecta Properties of Engine-Driven Supernovae from Observables in Their Initial Phase
• A precursor interpretation for the Crab supernova 1054 A.D. very early light curve