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arXiv · 1904.09645

Towards Efficient Detection of Small Near-Earth Asteroids Using the Zwicky Transient Facility (ZTF)

Quanzhi Ye·Frank J. Masci·Hsing Wen Lin·Bryce Bolin·Chan-Kao Chang·Dmitry A. Duev·George Helou·Wing-Huen Ip·David L. Kaplan·Emily Kramer·Ashish Mahabal·Chow-Choong Ngeow·Avery J. Nielsen·Thomas A. Prince·Hanjie Tan·Ting-Shuo Yeh·Eric C. Bellm·Richard Dekany·Matteo Giomi·Matthew J. Graham·Shrinivas R. Kulkarni·Thomas Kupfer·Russ R. Laher·Ben Rusholme·David L. Shupe·Charlotte Ward
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Abstract

We describe ZStreak, a semi-real-time pipeline specialized in detecting small, fast-moving near-Earth asteroids (NEAs) that is currently operating on the data from the newly-commissioned Zwicky Transient Facility (ZTF) survey. Based on a prototype originally developed by Waszczak et al. (2017) for the Palomar Transient Factory (PTF), the predecessor of ZTF, ZStreak features an improved machine-learning model that can cope with the $10\times$ data rate increment between PTF and ZTF. Since its first discovery on 2018 February 5 (2018 CL), ZTF/ZStreak has discovered $45$ confirmed new NEAs over a total of 232 observable nights until 2018 December 31. Most of the discoveries are small NEAs, with diameters less than $\sim100$ m. By analyzing the discovery circumstances, we find that objects having the first to last detection time interval under 2 hr are at risk of being lost. We will further improve real-time follow-up capabilities, and work on suppressing false positives using deep learning.

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Quanzhi Ye, Frank J. Masci, Hsing Wen Lin, Bryce Bolin, Chan-Kao Chang, Dmitry A. Duev, George Helou, Wing-Huen Ip, David L. Kaplan, Emily Kramer, Ashish Mahabal, Chow-Choong Ngeow, Avery J. Nielsen, Thomas A. Prince, Hanjie Tan, Ting-Shuo Yeh, Eric C. Bellm, Richard Dekany, Matteo Giomi, Matthew J. Graham, Shrinivas R. Kulkarni, Thomas Kupfer, Russ R. Laher, Ben Rusholme, David L. Shupe, Charlotte Ward. 2019-04-21. Towards Efficient Detection of Small Near-Earth Asteroids Using the Zwicky Transient Facility (ZTF). https://doi.org/10.1088/1538-3873%2Fab1b18

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