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arXiv · 1905.02209

The Zwicky Transient Facility: Surveys and Scheduler

Eric C. Bellm·Shrinivas R. Kulkarni·Tom Barlow·Ulrich Feindt·Matthew J. Graham·Ariel Goobar·Thomas Kupfer·Chow-Choong Ngeow·Peter Nugent·Eran Ofek·Thomas A. Prince·Reed Riddle·Richard Walters·Quan-Zhi Ye
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Abstract

We present a novel algorithm for scheduling the observations of time-domain imaging surveys. Our Integer Linear Programming approach optimizes an observing plan for an entire night by assigning targets to temporal blocks, enabling strict control of the number of exposures obtained per field and minimizing filter changes. A subsequent optimization step minimizes slew times between each observation. Our optimization metric self-consistently weights contributions from time-varying airmass, seeing, and sky brightness to maximize the transient discovery rate. We describe the implementation of this algorithm on the surveys of the Zwicky Transient Facility and present its on-sky performance.

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Eric C. Bellm, Shrinivas R. Kulkarni, Tom Barlow, Ulrich Feindt, Matthew J. Graham, Ariel Goobar, Thomas Kupfer, Chow-Choong Ngeow, Peter Nugent, Eran Ofek, Thomas A. Prince, Reed Riddle, Richard Walters, Quan-Zhi Ye. 2019-05-06. The Zwicky Transient Facility: Surveys and Scheduler. https://doi.org/10.1088/1538-3873%2Fab0c2a

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