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arXiv · 1612.03275

Optical photometry and spectroscopy of the low-luminosity, broad-lined Ic supernova iPTF15dld

Abstract

Core-collapse stripped-envelope supernova (SN) explosions reflect the diversity of physical parameters and evolutionary paths of their massive star progenitors. We have observed the type Ic SN iPTF15dld (z = 0.047), reported by the Palomar Transient Factory. Spectra were taken starting 20 rest-frame days after maximum luminosity and are affected by a young stellar population background. Broad spectral absorption lines associated with the SN are detected over the continuum, similar to those measured for broad-lined, highly energetic SNe Ic. The light curve and maximum luminosity are instead more similar to those of low luminosity, narrow-lined Ic SNe. This suggests a behavior whereby certain highly-stripped-envelope SNe do not produce a large amount of Ni56, but the explosion is sufficiently energetic that a large fraction of the ejecta is accelerated to higher-than-usual velocities. We estimate SN iPTF15dld had a main sequence progenitor of 20-25 Msun, produced a Ni56 mass of ~0.1-0.2 Msun, had an ejecta mass of [2-10] Msun, and a kinetic energy of [1-18] e51 erg.

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E. Pian, L. Tomasella, E. Cappellaro, S. Benetti, P. A. Mazzali, C. Baltay, M. Branchesi, E. Brocato, S. Campana, C. Copperwheat, S. Covino, P. D'Avanzo, N. Ellman, A. Grado, A. Melandri, E. Palazzi, A. Piascik, S. Piranomonte, D. Rabinowitz, G. Raimondo, S. Smartt, I. A. Steele, M. Stritzinger, S. Yang, S. Ascenzi, M. Della Valle, A. Gal-Yam, F. Getman, G. Greco, C. Inserra, E. Kankare, L. Limatola, L. Nicastro, A. Pastorello, L. Pulone, A. Stamerra, L. Stella, G. Stratta, L. Tartaglia, M. Turatto. 2016-12-10. Optical photometry and spectroscopy of the low-luminosity, broad-lined Ic supernova iPTF15dld. https://doi.org/10.1093/mnras%2Fstw3247

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