TY - JOUR
T1 - Core-collapse explosions of Wolf–Rayet stars and the connection to Type IIb/Ib/Ic supernovae
AU - Dessart, L.
AU - Hillier, D.J.
AU - Livne, E.
AU - Yoon, S.C.
AU - Woosley, S.E.
AU - Waldman, R.
AU - Langer, N.
PY - 2011
Y1 - 2011
N2 - We present non-Local Thermodynamic Equilibrium (LTE) time-dependent radiative-transfer
simulations of supernova (SN) IIb/Ib/Ic spectra and light curves, based on ∼1051 erg pistondriven
ejecta, with and without 56Ni, produced from single and binary Wolf–Rayet (WR)
stars evolved at solar and sub-solar metallicities. Our bolometric light curves show a 10-
d long post-breakout plateau with a luminosity of 1–5 × 107 L , visually brighter by
10 mag than the progenitor WR star. In our 56Ni-rich models, with ∼3M ejecta masses,
this plateau precedes a 20 to 30 d long re-brightening phase initiated by the outwarddiffusing
heat wave powered by radioactive decay at depth. A larger ejecta mass or a
deeper 56Ni location increases the heat diffusion time and acts to both delay and broaden
the light-curve peak. Discriminating between the two effects requires spectroscopic modelling.
In low ejecta-mass models with moderate mixing, γ -ray leakage starts as early as
∼50 d after explosion and causes the nebular luminosity to steeply decline by ∼0.02 mag
d−1. Such signatures, which are observed in standard SNe IIb/Ib/Ic, are consistent with
low-mass progenitors derived from a binary-star population. We propose that the majority
of stars with an initial mass 20M yield SNe II-P if ‘effectively’ single, SNe IIb/
Ib/Ic if part of a close binary system, and SN-less black holes if more massive. Our ejecta,
with outer hydrogen mass fractions as low as 0.01 and a total hydrogen mass of 0.001M ,
yield the characteristic SN IIb spectral morphology at early times. However at later times,
∼15 d after the explosion, only Hα may remain as a weak absorption feature. Our binary
models, characterized by helium surface mass fractions of 0.85, systematically show He I
lines during the post-breakout plateau, irrespective of the 56Ni abundance. Synthetic spectra
show a strong sensitivity to metallicity, which offers the possibility to constrain it directly
from SN spectroscopic modelling.
AB - We present non-Local Thermodynamic Equilibrium (LTE) time-dependent radiative-transfer
simulations of supernova (SN) IIb/Ib/Ic spectra and light curves, based on ∼1051 erg pistondriven
ejecta, with and without 56Ni, produced from single and binary Wolf–Rayet (WR)
stars evolved at solar and sub-solar metallicities. Our bolometric light curves show a 10-
d long post-breakout plateau with a luminosity of 1–5 × 107 L , visually brighter by
10 mag than the progenitor WR star. In our 56Ni-rich models, with ∼3M ejecta masses,
this plateau precedes a 20 to 30 d long re-brightening phase initiated by the outwarddiffusing
heat wave powered by radioactive decay at depth. A larger ejecta mass or a
deeper 56Ni location increases the heat diffusion time and acts to both delay and broaden
the light-curve peak. Discriminating between the two effects requires spectroscopic modelling.
In low ejecta-mass models with moderate mixing, γ -ray leakage starts as early as
∼50 d after explosion and causes the nebular luminosity to steeply decline by ∼0.02 mag
d−1. Such signatures, which are observed in standard SNe IIb/Ib/Ic, are consistent with
low-mass progenitors derived from a binary-star population. We propose that the majority
of stars with an initial mass 20M yield SNe II-P if ‘effectively’ single, SNe IIb/
Ib/Ic if part of a close binary system, and SN-less black holes if more massive. Our ejecta,
with outer hydrogen mass fractions as low as 0.01 and a total hydrogen mass of 0.001M ,
yield the characteristic SN IIb spectral morphology at early times. However at later times,
∼15 d after the explosion, only Hα may remain as a weak absorption feature. Our binary
models, characterized by helium surface mass fractions of 0.85, systematically show He I
lines during the post-breakout plateau, irrespective of the 56Ni abundance. Synthetic spectra
show a strong sensitivity to metallicity, which offers the possibility to constrain it directly
from SN spectroscopic modelling.
U2 - 10.1111/j.1365-2966.2011.18598.x
DO - 10.1111/j.1365-2966.2011.18598.x
M3 - Article
SN - 0035-8711
VL - 414
SP - 2985
EP - 3005
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -