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We present detailed optical photometry for 25 Type Ibc supernovae (SNe Ibc) within d ≈ 150 Mpc obtained with the robotic Palomar 60-inch telescope in [2004][2005][2006][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 ≈ 10 d after V −band maximum is tightly distributed, (V − R) V 10 = 0.26 ± 0.06 mag. Using this technique, we find that SNe Ibc typically suffer from significant host galaxy extinction, E(B −V ) ≈ 0.4 mag. A comparison of the extinction-corrected light curves for helium-rich (Type Ib) and helium-poor (Type Ic) SNe 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 (BL) 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 SN 2009bb) we find a 25% probability that relativistic SNe are drawn from the overall SNe Ic-BL population. Finally, we fit analytic models to the light curves to derive typical 56 Ni masses of M Ni ≈ 0.2 and 0.5 M ⊙ for SNe Ibc and SNe Ic-BL, respectively. With reasonable assumptions for the photospheric velocities, we further extract kinetic energy and ejecta mass values of M ej ≈ 2 M ⊙ and E K ≈ 10 51 erg for SNe Ibc, while for SNe Ic-BL we find higher values, M ej ≈ 5 M ⊙ and E K ≈ 10 52 erg. We discuss the implications for the progenitors of SNe Ibc and their relation to those of engine-driven explosions.

We have converted the Palomar 60-inch telescope (P60) from a classical night assistant-operated telescope to a fully robotic facility. The automated system, which has been operational since September 2004, is designed for moderately fast (t 3 minutes) and sustained (R 23 mag) observations of gamma-ray burst afterglows and other transient events. Routine queue-scheduled observations can be interrupted in response to electronic notification of transient events. An automated pipeline reduces data in real-time, which is then stored on a searchable web-based archive for ease of distribution. We describe here the design requirements, hardware and software upgrades, and lessons learned from roboticization. We present an overview of the current system performance as well as plans for future upgrades.

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