Maria R. Drout, Alicia M. Soderberg, A. Gal-Yam, S. B. Cenko, D. B. Fox, D. C. Leonard, D. J. Sand, D. -S. Moon, I. Arcavi, Y. Green
We present detailed optical photometry for 25 Type Ibc supernovae within
d\approx150 Mpc obtained with the robotic Palomar 60-inch telescope in
2004-2007. This study represents the first uniform, systematic, and statistical
sample of multi-band SNe Ibc light curves available to date. We correct the
light curves for host galaxy extinction using a new technique based on the
photometric color evolution, namely, we show that the (V-R) color of
extinction-corrected SNe Ibc at t\approx10 days after V-band maximum is tightly
distributed, (V-R)=0.26+-0.06 mag. Using this technique, we find that SNe Ibc
typically suffer from significant host galaxy extinction, E(B-V)\approx0.4 mag.
A comparison of the extinction-corrected light curves for SNe Ib and Ic reveals
that they are statistically indistinguishable, both in luminosity and decline
rate. We report peak absolute magnitudes of M_R=-17.9+-0.9 mag and
M_R=-18.3+-0.6 mag for SNe Ib and Ic, respectively. Focusing on the broad-lined
SNe Ic, we find that they are more luminous than the normal SNe Ibc sample,
M_R=-19.0+-1.1 mag, with a probability of only 1.6% that they are drawn from
the same population of explosions. By comparing the peak absolute magnitudes of
SNe Ic-BL with those inferred for local engine-driven explosions (GRB-SN
1998bw, XRF-SN 2006aj, and SN2009bb) we find a 25% probability that they are
drawn from the SNe Ic-BL population. Finally, we fit analytic models to the
light-curves to derive typical Ni-56 masses of M_Ni \approx0.2 and 0.5 M_sun
for SNe Ibc and SNe Ic-BL, respectively. With reasonable assumptions for the
photospheric velocities, we extract kinetic energy and ejecta mass values of
M_ej \approx 2 M_sun and E_K\approx1e+51 erg for SNe Ibc, while for SNe Ic-BL
we find higher values, M_ej\approx5 M_sun and E_K\approx1e+52 erg. We discuss
the implications for the progenitors of SNe Ibc and their relation to
engine-driven explosions [ABRIDGED].
View original:
http://arxiv.org/abs/1011.4959
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