Metallicities from high-resolution spectra of 49 RR Lyrae variables

Gilligan, Christina K.; Chaboyer, Brian; Marengo, Massimo; Mullen, Joseph P.; Bono, Giuseppe; Braga, Vittorio F.; Crestani, Juliana; Dall'Ora, Massimo; Fiorentino, Giuliana; Monelli, Matteo; Neeley, Jill R.; Fabrizio, Michele; Martínez-Vázquez, Clara E.; Thévenin, Frédéric; Sneden, Christopher
Bibliographical reference

Monthly Notices of the Royal Astronomical Society

Advertised on:
6
2021
Number of authors
15
IAC number of authors
1
Citations
19
Refereed citations
15
Description
Accurate metallicities of RR Lyrae are extremely important in constraining period-luminosity-metallicity (PLZ) relationships, particularly in the near-infrared. We analyse 69 high-resolution spectra of Galactic RR Lyrae stars from the Southern African Large Telescope. We measure metallicities of 58 of these RR Lyrae stars with typical uncertainties of 0.15 dex. All but one RR Lyrae in this sample has accurate ( $\sigma _{\varpi }\lesssim 10{{\ \rm per\ cent}}$ ) parallax from Gaia. Combining these new high-resolution spectroscopic abundances with similar determinations from the literature for 93 stars, we present new PLZ relationships in WISE W1 and W2 magnitudes, and the Wesenheit magnitudes W(W1, V - W1) and W(W2, V - W2).
Related projects
A view of our Milky Way galaxy with its close neighbors the Magellanic Clouds
Galaxy Evolution in the Local Group
Galaxy formation and evolution is a fundamental Astrophysical problem. Its study requires “travelling back in time”, for which there are two complementary approaches. One is to analyse galaxy properties as a function of red-shift. Our team focuses on the other approach, called “Galactic Archaeology”. It is based on the determination of galaxy
Matteo
Monelli