Related papers: Mid-infrared PL relations for Globular Cluster RR …
On the basis of an extended set of nonlinear convective RR Lyrae pulsation models we derive the first theoretical light curves in the Gaia bands and the corresponding intensity-weighted mean magnitudes and pulsation amplitudes. The effects…
Because of strong and spatially highly variable interstellar extinction and extreme source crowding, the faint (K>15) stellar population in the Milky Way's nuclear cluster is still poorly studied. RR Lyrae stars provide us with a tool to…
We have begun developing a new metallicity calibration for RR Lyrae stars that includes high-temperature phase regions. Our calibration is an updated and expanded version of the Delta-S, equivalent width method, but which is applicable for…
We present a new distance estimation for the Milky Way dwarf spheroidal satellite Sculptor obtained from multi-epoch mid-infrared observations of RR Lyrae stars. The 3.6 {\mu}m observations have been acquired with the Infrared Array Camera…
Recent Hipparcos results have lent support to the idea that RR Lyrae variables in the halo field and in globular clusters differ in luminosity by ~0.2mag. In this Letter, we study the pulsation properties of RR Lyraes in clusters with…
We present results from the analysis of 2997 fundamental mode RR Lyrae variables located in the Small Magellanic Cloud (SMC). For these objects near-infrared time-series photometry from the VISTA survey of the Magellanic Clouds system (VMC)…
We use double-mode RR Lyrae (RRd) stars from the MACHO variable star database of the Large Magellanic Cloud (LMC) to estimate its distance, by utilizing photometric data, linear pulsation and stellar atmosphere models. If we set…
We present new statistical parallax solutions for the absolute magnitude and kinematics of RR Lyrae stars. New proper motion, radial velocity, and abundance data are used; the new data set is 50% larger, and of higher quality, than…
We present a Bayesian analysis of the distances to 15,040 Large Magellanic Cloud (LMC) RR Lyrae stars using $V$- and $I$-band light curves from the Optical Gravitational Lensing Experiment, in combination with new $z$-band observations from…
We present results from the theoretical modelling of the observed B,V light curves of 14 RR Lyrae stars in the Large Magellanic Cloud. The sample includes 7 fundamental and 7 first overtone pulsators covering the metallicity range from…
We present observations of RR Lyrae variables in the Local Group late-type spiral galaxy M33. Using the Advanced Camera for Surveys on the Hubble Space Telescope, we have identified 64 ab-type RR Lyraes in M33. We have estimated reddenings…
We present a detailed light curve analysis of RR Lyrae variables at multiple wavelengths using Fourier decomposition method. The time-series data for RR Lyrae variables in the Galactic bulge and the Magellanic Clouds are taken from the…
The universality of the Cepheid Period-Luminosity relations has been under discussion since metallicity effects have been assumed to play a role in the value of the intercept and, more recently, of the slope of these relations. The goal of…
We briefly describe a method of obtaining relative intrinsic stellar parameters, such as absolute magnitudes and colors from the light curves of fundamental mode RR Lyrae (RRab) stars. Absolute stellar parameters of double-mode variables…
Metallicities ([Fe/H]) from low resolution spectroscopy obtained with the Very Large Telescope (VLT) are presented for 98 RR Lyrae and 3 short period Cepheids in the bar of the Large Magellanic Cloud. Our metal abundances have typical…
(Abridged) We have surveyed four globular clusters in the Fornax dwarf galaxy for RR Lyrae stars, using archival HST observations. We identify 197 new RR Lyrae stars in these four clusters. Despite the short observational baseline, we…
The Large Magellanic Cloud (LMC) is widely considered a corner-stone of the astronomical distance scale, however a difference of 0.2-0.3 mag exists in its distance as predicted by the "short" and "long" distance scales. Distances to the LMC…
Observational bias against finding Milky Way (MW) dwarf galaxies at low Galactic latitudes (b < 20 deg) and at low surface brightnesses (fainter than 29 mag arcsec^-2, in the V-band) currently limits our understanding of the faintest limits…
We investigate the properties of the so-called BL Her stars, i.e., Population II Cepheids with periods shorter than 8 days, using updated pulsation models and evolutionary tracks computed adopting a metal abundance in the range of Z=0.0001…
Period-luminosity relations (PLRs) of type II Cepheids (T2Cs) in the Small Magellanic Cloud are derived based on OGLE-III, IRSF/SIRIUS and other data, and these are compared with results for the Large Magellanic Cloud and Galactic globular…