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arXiv · 2302.10929

The Evryscope Fast Transient Engine: Real-Time Detection for Rapidly Evolving Transients

Hank Corbett·Jonathan Carney·Ramses Gonzalez·Octavi Fors·Nathan Galliher·Amy Glazier·Ward S. Howard·Nicholas M. Law·Robert Quimby·Jeffrey K. Ratzloff·Alan Vasquez Soto
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Abstract

Astrophysical transients with rapid development on sub-hour timescales are intrinsically rare. Due to their short durations, events like stellar superflares, optical flashes from gamma-ray bursts, and shock breakouts from young supernovae are difficult to identify on timescales that enable spectroscopic followup. This paper presents the Evryscope Fast Transient Engine (EFTE), a new data reduction pipeline designed to provide low-latency transient alerts from the Evryscopes, a North-South pair of ultra-wide-field telescopes with an instantaneous footprint covering 38% of the entire sky, and tools for building long-term light curves from Evryscope data. EFTE leverages the optical stability of the Evryscopes by using a simple direct image subtraction routine suited to continuously monitoring the transient sky at minute cadence. Candidates are produced within the base Evryscope two-minute cadence for 98.5% of images, and internally filtered using VetNet, a convolutional neural network real-bogus classifier. EFTE provides an extensible, robust architecture for transient surveys probing similar timescales, and serves as the software testbed for the real-time analysis pipelines and public data distribution systems for the Argus Array, a next generation all-sky observatory with a data rate 62x higher than Evryscope.

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Hank Corbett, Jonathan Carney, Ramses Gonzalez, Octavi Fors, Nathan Galliher, Amy Glazier, Ward S. Howard, Nicholas M. Law, Robert Quimby, Jeffrey K. Ratzloff, Alan Vasquez Soto. 2023-02-21. The Evryscope Fast Transient Engine: Real-Time Detection for Rapidly Evolving Transients. https://doi.org/10.3847/1538-4365/acbd41

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