Investigating the properties of stripped-envelope supernovae; what are the implications for their progenitors?

We present observations and analysis of 18 stripped-envelope supernovae observed during 2013 -- 2018. This sample consists of 5 H/He-rich SNe, 6 H-poor/He-rich SNe, 3 narrow lined SNe Ic and 4 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 $ =2.8\pm{1.5}$ Msun which further strengthens the evidence that SE-SNe arise from low mass progenitors which are typically $ $ and lack of clear bimodality in the distribution implies $<30$ Msun progenitors and that envelope stripping via binary interaction is the dominant evolutionary pathway of these SNe.