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This content will become publicly available on April 14, 2026

Title: Photometric Metallicity and Distance Estimates for ∼70,000 RR Lyrae Stars from the Zwicky Transient Facility
Abstract Utilizing Zwicky Transient Facility (ZTF) data and existing RR Lyrae stars (RRLs) catalogs, this study achieves the first calibration of theP−ϕ31−R21− [Fe/H] andP−ϕ31−A2−A1− [Fe/H] relations in the ZTF photometric system for RRab and RRc stars. We also recalibrate the period–absolute magnitude–metallicity (PMZ) and period–Wesenheit–metallicity (PWZ) relations in the ZTFgribands for RRab and RRc stars. Based on nearly 4100 stars with precise measurements ofP,ϕ31,A2, andA1, and available spectroscopic metallicity estimates, the photometric metallicity relations exhibit strong internal consistency across different bands, supporting the use of a weighted averaging method for the final estimates. The photometric metallicity estimates of globular clusters based on RR Lyrae members also show excellent agreement with high-resolution spectroscopic measurements, with a typical scatter of 0.15 dex for RRab stars and 0.14 dex for RRc stars, respectively. Using hundreds of local RRLs with newly derived photometric metallicities and precise Gaia Data Release 3 parallaxes, we establish the PMZ and PWZ relations in multiple bands. Validation with globular cluster RR Lyrae members reveals typical distance errors of 3.1% and 3.0% for the PMZ relations, and 3.1% and 2.6% for the PWZ relations for RRab and RRc stars, respectively. Compared to PMZ relations, the PWZ relations are tighter and almost unbiased, making them the recommended choice for distance calculations. We present a catalog of 73,795 RRLs with precise photometric metallicities; over 95% of them have accurate distance measurements. Compared to Gaia DR3, approximately 25,000 RRLs have precise photometric metallicities and distances derived for the first time.  more » « less
Award ID(s):
1927130
PAR ID:
10649111
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
IOP
Date Published:
Journal Name:
The Astrophysical Journal Supplement Series
Volume:
278
Issue:
1
ISSN:
0067-0049
Page Range / eLocation ID:
2
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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