Metallicities from high-resolution spectra of 49 RR Lyrae variables

Gilligan, C. K.; Chaboyer, Brian; Marengo, Massimo; Mullen, J. P.; Bono, G.; Braga, V. F.; Crestani, Juliana; Dall’Ora, M.; Fiorentino, G.; Monelli, M.; Neeley, J.; Fabrizio, M.; Martı́nez-Vázquez, C. E.; Thévenin, F.; Sneden, Christopher

doi:10.1093/mnras/stab857

Cited by 16 publications

(16 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With this sample size the slopes of the PL relations are not entirely apparent, especially for the RRc stars, but the increase in brightness with the period can be seen. K -band brightness is much less sensitive to interstellar extinction than shorter wavelengths, limiting the spread of the PL relation, although for RR Lyrae stars the spread of the PL rela- tion is largely driven by metallicity (Catelan et al 2004;Layden et al 2019;Bhardwaj et al 2021;Gilligan et al 2021). Furthermore, not all stars have their K brightness measured (here, 32 of the 118 targets are missing from the lower plots), and even when they do, singleepoch measurements may not represent mean brightness values.…”

Section: Period-luminosity Relations and Colorsmentioning

confidence: 98%

First results on RR Lyrae stars with the TESS space telescope: untangling the connections between mode content, colors and distances

Molnár,

Bódi,

Pál

et al. 2021

Preprint

View full text Add to dashboard Cite

The TESS space telescope is collecting continuous, high-precision optical photometry of stars throughout the sky, including thousands of RR Lyrae stars. In this paper, we present results for an initial sample of 118 nearby RR Lyrae stars observed in TESS Sectors 1 and 2. We use differentialimage photometry to generate light curves and analyse their mode content and modulation properties. We combine accurate light curve parameters from TESS with parallax and color information from the

show abstract

Section: Period-luminosity Relations and Colorsmentioning

confidence: 98%

First results on RR Lyrae stars with the TESS space telescope: untangling the connections between mode content, colors and distances

Molnár,

Bódi,

Pál

et al. 2021

Preprint

View full text Add to dashboard Cite

show abstract

“…The metallicities were compiled by Fernley et al (1998), with a typical uncertainty of 0.15 dex. Recently, Gilligan et al (2021) measured updated metallicities for a sample of MW RR Lyrae that includes a majority of the stars in the Neeley et al (2017) sample. We compared the metallicities reported by Fernley et al (1998) and Gilligan et al (2021) and found them broadly consistent (median absolute difference of 0.15 dex, comparable to the reported uncertainties for both samples).…”

Section: Mw Calibration Samplementioning

confidence: 99%

RR Lyrae-based Distances for 39 Nearby Dwarf Galaxies Calibrated to Gaia eDR3

Nagarajan

Weisz

El-Badry

2022

ApJ

View full text Add to dashboard Cite

We provide uniform RR Lyrae-based distances to 39 dwarf galaxies in and around the Local Group. We determine distances based on a Bayesian hierarchical model that uses periods and magnitudes of published RR Lyrae in dwarf galaxies and is anchored to well-studied Milky Way (MW) RR Lyrae with spectroscopic metallicities and Gaia eDR3 parallaxes. Gaia eDR3 parallaxes for the anchor sample are a factor of 2, on average, more precise than DR2 parallaxes, and allow for a much better constrained period–luminosity–metallicity relation. While ∼75% of our distances are within 1σ of recent RR Lyrae distances in the literature, our distances are also ∼2–3 times more precise than distances in the literature, on average. On average, our distances are ∼0.05 mag closer than distances in the literature, as well as ∼0.06 mag closer than distances derived using a theoretical period–luminosity–metallicity relation. These discrepancies are largely due to our eDR3 parallax anchor. We show that the Hipparcos-anchored RR Lyrae distance scale of Carretta et al. overpredicts distances to MW RR Lyrae by ∼0.05 mag. The largest uncertainties in our distances are (i) the lack of direct metallicity measurements for RR Lyrae and (ii) the heterogeneity of published RR Lyrae photometry. We provide simple formulae to place new dwarf galaxies with RR Lyrae on a common distance scale with this work. We provide a public code that can easily incorporate additional galaxies and data from future surveys, providing a versatile framework for the cartography of the local universe with RR Lyrae.

show abstract

“…As the cluster RRLs adopted in this work cover roughly 1 dex in the intermediate metal regime, we collected the data of the reference stars from a large sample of high-resolution spectroscopic surveys of RRLs Nemec et al 2013;Govea et al 2014;Chadid et al 2017;Sneden et al 2017;Magurno et al 2019;Crestani et al 2021;Gilligan et al 2021), with the metallicities of RRLs ranging from −3.0 dex to solar or super-solar iron abundance based on those high-resolution spectra. We cross match the catalog of those studies with our data for the reference stars.…”

Section: Comparison Of Rrab Stars In Gcs and The Large Magellanic Clo...mentioning

confidence: 99%

“…The metallicities of RRLs in those studies have been highlighted for a reliable estimation of distance with the period-luminosity-metallicity relation. But it is difficult to obtain accurate measurements of metal abundances of this type of star Govea et al 2014;Nemec et al 2013;Sneden et al 2017;Chadid et al 2017;Magurno et al 2019;Crestani et al 2021;Gilligan et al 2021). Arellano Ferro (2022) reported a homogeneous approach toward the calculation of mean M V and [Fe/H] with a sample of 37 globular clusters (GCs) via Fourier decomposition of their light curves.…”

Section: Introductionmentioning

confidence: 99%

A Study of the Pulsation Properties of 57 Non-Blazhko Ab-type RR Lyrae Stars with Homogeneous Metallicities from the LAMOST–Kepler/K2 Survey

Zong

Wang

et al. 2023

ApJ

View full text Add to dashboard Cite

Homogeneous metallicities and continuous high-precision light curves play key roles in studying the pulsation properties of RR Lyrae stars. By cross matching LAMOST DR6 with the Kepler and K2 fields, we have determined seven and 50 non-Blazhko RRab stars, respectively, that have homogeneous metallicities determined from low-resolution spectra of the LAMOST–Kepler/K2 survey. The Fourier decomposition method is applied to the light curves of these stars provided by the Kepler space-based telescope to determine the fundamental pulsation periods and parameters. The calculated amplitude ratios of R 21, R 31 and the phase differences of ϕ 21, ϕ 31 are consistent with the parameters of RRab stars in both globular clusters and the Large Magellanic Cloud. We find a linear relationship between the phase differences ϕ 21 and ϕ 31, which is in good agreement with the results in the literature. As far as the amplitude, we find that the amplitude of primary frequency A 1 and the total amplitude A tot follow either a cubic or linear relationship. For the rise time, we do not find its relevance with the period of the fundamental pulsation mode P1, or A tot and ϕ 21. However, it might follow a linear relationship with R 31. Based on the homogeneous metallicities, we have derived a new calibration formula for the period–ϕ 31–[Fe/H] relation, which agrees well with previous studies.

show abstract

Metallicities from high-resolution spectra of 49 RR Lyrae variables

Cited by 16 publications

References 64 publications

First results on RR Lyrae stars with the TESS space telescope: untangling the connections between mode content, colors and distances

First results on RR Lyrae stars with the TESS space telescope: untangling the connections between mode content, colors and distances

RR Lyrae-based Distances for 39 Nearby Dwarf Galaxies Calibrated to Gaia eDR3

A Study of the Pulsation Properties of 57 Non-Blazhko Ab-type RR Lyrae Stars with Homogeneous Metallicities from the LAMOST–Kepler/K2 Survey

Contact Info

Product

Resources

About