Four (Super)luminous Supernovae from the First Months of the ZTF Survey

Understand

We present photometry and spectroscopy of four hydrogen-poor luminous supernovae discovered during the two-month science commissioning and early operations of the Zwicky Transient Facility (ZTF) survey.

• Three of these objects, SN2018bym (ZTF18aapgrxo), SN2018avk (ZTF18aaisyyp) and SN2018bgv (ZTF18aavrmcg) resemble typical SLSN-I spectroscopically, while SN2018don (ZTF18aajqcue) may be an object similar to SN2007bi experiencing considerable host galaxy reddening, or an intrinsically long-lived, luminous and red SN Ic.
• We analyze the light curves, spectra, and host galaxy properties of these four objects and put them in context of the population of SLSN-I.
• SN2018bgv stands out as the fastest-rising SLSN-I observed to date, with a rest-frame g-band rise time of just 10 days from explosion to peak -- if it is powered by magnetar spin-down, the implied ejecta mass is only ~1 M$_{\odot}$.