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Title: Identifying RR Lyrae in the ZTF DR3 data set
ABSTRACT

We present an RR Lyrae (RRL) catalogue based on the combination of the third data release of the Zwicky Transient Facility (ZTF DR3) and Gaia EDR3. We use a multistep classification pipeline relying on the Fourier decomposition fitting to the multiband ZTF light curves and random forest classification. The resulting catalogue contains 71 755 RRLs with period and light-curve parameter measurements and has a completeness of 0.92 and a purity of 0.92 with respect to the Specific Objects Study Gaia DR2 RRLs. The catalogue covers the Northern sky with declination ≥−28°, its completeness is ≳0.8 for heliocentric distance ≤80 kpc, and the most distant RRL is at 132 kpc. Compared with several other RRL catalogues covering the Northern sky, our catalogue has more RRLs around the Galactic halo and is more complete at low-Galactic latitude areas. Analysing the spatial distribution of RRL in the catalogue reveals the previously known major overdensities of the Galactic halo, such as the Virgo overdensity and the Hercules–Aquila Cloud, with some evidence of an association between the two. We also analyse the Oosterhoff fraction differences throughout the halo, comparing it with the density distribution, finding increasing Oosterhoff I fraction at the elliptical radii between 16 and 32 kpc and some evidence of different Oosterhoff fractions across various halo substructures.

 
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Award ID(s):
1813881 1909584
NSF-PAR ID:
10361557
Author(s) / Creator(s):
;
Publisher / Repository:
Oxford University Press
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
510
Issue:
3
ISSN:
0035-8711
Page Range / eLocation ID:
p. 3575-3588
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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