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arXiv · 1708.04629

Mary, a pipeline to aid discovery of optical transients

Igor Andreoni·Colin Jacobs·Sarah Hegarty·Tyler Pritchard·Jeff Cooke·Stuart Ryder
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Abstract

The ability to quickly detect transient sources in optical images and trigger multi-wavelength follow up is key for the discovery of fast transients. These include events rare and difficult to detect such as kilonovae, supernova shock breakout, and "orphan" Gamma-ray Burst afterglows. We present the Mary pipeline, a (mostly) automated tool to discover transients during high-cadenced observations with the Dark Energy Camera (DECam) at CTIO. The observations are part of the "Deeper Wider Faster" program, a multi-facility, multi-wavelength program designed to discover fast transients, including counterparts to Fast Radio Bursts and gravitational waves. Our tests of the Mary pipeline on DECam images return a false positive rate of ~2.2% and a missed fraction of ~3.4% obtained in less than 2 minutes, which proves the pipeline to be suitable for rapid and high-quality transient searches. The pipeline can be adapted to search for transients in data obtained with imagers other than DECam.

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Igor Andreoni, Colin Jacobs, Sarah Hegarty, Tyler Pritchard, Jeff Cooke, Stuart Ryder. 2017-08-15. Mary, a pipeline to aid discovery of optical transients. https://doi.org/10.1017/pasa.2017.33

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