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  • The Galactic bulge exploration: I. The period–absolute magnitude–metallicity relations for RR Lyrae stars for G BP , V, G, G RP , I, J, H , and K s passbands using Gaia DR3 parallaxes
Title: The Galactic bulge exploration: I. The period–absolute magnitude–metallicity relations for RR Lyrae stars for G BP , V, G, G RP , I, J, H , and K s passbands using Gaia DR3 parallaxes
We present a new set of period–absolute magnitude–metallicity (PMZ) relations for single-mode RR Lyrae stars calibrated for the opticalGBP,V,G,GRP, near-infraredI,J,H, andKspassbands. We compiled a large dataset (over 100 objects) of fundamental and first-overtone RR Lyrae pulsators consisting of mean intensity magnitudes, reddenings, pulsation properties, iron abundances, and parallaxes measured by theGaiaastrometric satellite in its third data release. Our newly calibrated PMZ relations encapsulate the most up-to-date ingredients in terms of both data and methodology. They are intended to be used in conjunction with large photometric surveys targeting the Galactic bulge, including the Optical Gravitational Lensing Experiment (OGLE), the Vista Variables in the Vía Láctea Survey (VVV), and theGaiacatalog. In addition, our Bayesian probabilistic approach provides accurate uncertainty estimates of the predicted absolute magnitudes of individual RR Lyrae stars. Our derived PMZ relations provide consistent results when compared to benchmark distances to globular clusters NGC 6121 (also known as M 4), NGC 5139 (also known as omega Cen), and Large and Small Magellanic Clouds, which are stellar systems rich in RR Lyrae stars. Lastly, ourKs-band PMZ relations match well with the previously published PMZ relations based onGaiadata and accurately predict the distance toward the prototype of this class of variables, the eponymic RR Lyr itself.  more » « less
Award ID(s):
2009836
PAR ID:
10534432
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Astronomy & Astrophysics, Volume 684, id.A176, 13 pp.
Date Published:
Journal Name:
Astronomy & Astrophysics
Volume:
684
ISSN:
0004-6361
Page Range / eLocation ID:
A176
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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