Prentice, S.J. and Ashall, C. and James, P.A. and Short, L. and Mazzali, P.A. and Bersier, D. and Crowther, P.A. and Barbarino, C. and Chen, T.-W. and Copperwheat, C.M. and Darnley, M.J. and Denneau, L. and Elias-Rosa, N. and Fraser, M. and Galbany, L. and Gal-Yam, A. and Harmanen, J. and Howell, D.A. and Hosseinzadeh, G. and Inserra, C. and Kankare, E. and Karamehmetoglu, E. and Lamb, G.P. and Limongi, M. and Maguire, K. and McCully, C. and Olivares, F. and Piascik, A.S. and Pignata, G. and Reichart, D.E. and Rest, A. and Reynolds, T. and Rodríguez, Ó. and Saario, J.L.O. and Schulze, S. and Smartt, S.J. and Smith, K.W. and Sollerman, J. and Stalder, B. and Sullivan, M. and Taddia, F. and Valenti, S. and Vergani, S.D. and Williams, S.C. and Young, D.R. (2019) Investigating the properties of stripped-envelope supernovae; what are the implications for their progenitors? Monthly Notices of the Royal Astronomical Society, 485 (2). pp. 1559-1578. ISSN 0035-8711
Abstract
We present observations and analysis of 18 stripped-envelope supernovae observed during 2013–2018. This sample consists of five H/He-rich SNe, six H-poor/He-rich SNe, three narrow lined SNe Ic, and four broad lined SNe Ic. The peak luminosity and characteristic time-scales of the bolometric light curves are calculated, and the light curves modelled to derive 56Ni and ejecta masses (MNi and Mej). Additionally, the temperature evolution and spectral line velocity curves of each SN are examined. Analysis of the [O I] line in the nebular phase of eight SNe suggests their progenitors had initial masses <20 M⊙. The bolometric light curve properties are examined in combination with those of other SE events from the literature. The resulting data set gives the Mej distribution for 80 SE–SNe, the largest such sample in the literature to date, and shows that SNe Ib have the lowest median Mej, followed by narrow-lined SNe Ic, H/He-rich SNe, broad-lined SNe Ic, and finally gamma-ray burst SNe. SNe Ic-6/7 show the largest spread of Mej ranging from ∼1.2–11 M⊙, considerably greater than any other subtype. For all SE–SNe <Mej> = 2.8 ± 1.5 M⊙ which further strengthens the evidence that SE–SNe arise from low-mass progenitors which are typically <5 M⊙ at the time of explosion, again suggesting MZAMS <25 M⊙. The low <Mej> and lack of clear bimodality in the distribution implies <30 M⊙ progenitors and that envelope stripping via binary interaction is the dominant evolutionary pathway of these SNe.