Wide-Field Telescope Observations of Supernovae

Abstract

The explosive universe of supernovae has been transformed from a slow target-by-target activity into a systematic census of the variable universe thanks to the advent of wide-field survey telescopes; this paper reviews this transition and its scientific consequences. Survey capability is not just a function of collecting area, as the five representative facilities examined here, ASAS-SN, ATLAS, Pan-STARRS, the Zwicky Transient Facility, and the Vera C. Rubin Observatory, demonstrate – they have an étendue of collecting area times field of view that varies by over two orders of magnitude among the facilities and is largest for Rubin. This increase in instrumental grasp, combined with an automated pipeline of difference imaging, the vetting of supernovae by means of machine-learning "real–bogus" classification, alert brokering, and photometric classification has led to a roughly tenfold increase in the annual number of classified supernovae and a growing discrepancy between supernova detection and spectroscopic confirmation. The samples produced are large and uniform enough to relate light-curve shape to progenitor channels, the core collapse of massive stars, and thermonuclear disruption of white dwarfs, and effectively use Type Ia supernovae as standardizable distance indicators, the key to the discovery of cosmic acceleration and current constraints on dark energy. Modern supernova astronomy is productive only through the integration of observing strategy with data analysis, not through either alone.