Related papers: RR Lyrae stars seen from space

RR Lyrae stars are pulsating stars, many of which also show a long-term variation called the Blazhko effect which is a modulation of amplitude and phase of the lightcurve. In this work, we searched for the incidence rate of the Blazhko…

The extended photometry available for XZ Dra, a Blazhko type RR Lyrae star, makes it possible to study its long-term behavior. It is shown that its pulsation period exhibit cyclic, but not strictly regular variations with approx. 7200 d…

We present a detailed nonlinear dynamical investigation of the Blazhko modulation of the Kepler RR Lyrae star V783 Cyg (KIC 5559631). We used different techniques to produce modulation curves, including the determination of amplitude…

In an extended photometric campaign of RR Lyrae variables of the globular cluster M3, an aberrant light-curve, non-Blazhko RRab star, V123, was detected. Based on its brightness, colors and radial velocity curve, V123 is a bona fide member…

We used the GEOS database to study the Blazhko effect of galactic RRab stars. The database is continuously enriched by maxima supplied by amateur astronomers and by a dedicated survey by means of the two TAROT robotic telescopes. The same…

We report the discovery of a new group of double-periodic RR Lyrae stars from the analysis of the OGLE-IV Galactic bulge photometry. In 11 stars identified in the OGLE catalog as first overtone pulsators (RRc stars) we detect additional…

We reanalyzed the c-type RR Lyrae star BE Dor (MACHO 5.4644.8, OGLE-LMC-RRLYR-06002) that had been discovered to show cyclic period changes. The photometric data of several sky surveys (DASCH, MACHO, OGLE, ASAS-SN, and TESS) were used for…

Hydrogen emissions of RR Lyrae variables are the imprints of shock waves traveling through their atmospheres. We develop a pattern recognition algorithm, which is then applied to single-epoch spectra of SDSS and LAMOST. These two…

We present an overview and current status of research on RR Lyrae stars in binary systems. In present days the number of binary candidates has steeply increased and suggested that multiple stellar systems with an RR Lyrae component is much…

I report some results of an echelle spectroscopic survey of RR Lyrae stars begun in 2006 that I presented in my Henry Norris Lecture of January 4, 2010. Topics include (1) atmospheric velocity gradients, (2) phase-dependent envelope…

We analyzed the long and short cadence light curves of the Kepler non-Blazhko RRab stars. We prepared the Fourier spectra, the Fourier amplitude and phase variation functions, time-frequency representation, the O-C diagrams and their…

DM Cyg, a fundamental mode RRab star was observed in the 2007 and 2008 seasons in the frame of the Konkoly Blazhko Survey. Very small amplitude light curve modulation was detected with 10.57 d modulation period. The maximum brightness and…

We present the results of collaborative observations of three RR Lyrae stars (CX Lyr, NU Aur and VY CrB) which have a strong Blazhko effect. This work has been initiated and performed in the framework of the GEOS RR Lyr Survey (Groupe…

We present our results of searching for differences in light curves of modulated and non-modulated RRab stars in the Galactic bulge. We examined a sample of more than 8000 stars. The most important results are that Blazhko stars have…

The Blazhko-phenomenon, the modulation of the pulsation of RR Lyrae stars remains one of the most stubborn unsolved problems of stellar pulsation. The recent idea of Stothers proposes that periodic variations in the properties of the…

We present some recent findings concerning the use of RR Lyrae as distance indicators and stellar tracers. We outline pros and cons of field and cluster RR Lyrae stars and discuss recent theoretical findings concerning the use of the Bailey…

We have obtained the most extensive and most accurate photometric data of a Blazhko variable MW Lyr during the 2006-2007 observing seasons. The data within each 0.05 phase bin of the modulation period (P_m=1/f_m) cover the entire light…

LINEAR 1169665 is a RR Lyrae of sub-type c discovered by the asteroid survey LINEAR. The robotic telescope TAROT at Calern Observatory has observed it between the years 2006 and 2015. The present study of TAROT data as well as those from…

We report the discovery of a new case of an RR Lyrae star that experienced a switching of its pulsation mode. We detected USNO-B1.0 1171-0309158 as a double-mode RR Lyrae star from observations of the Catalina surveys (CSS) that showed…

The Kepler space telescope revealed new, unexpected phenomena in RR Lyrae stars: period doubling and the possible presence of additional modes. Identifying these modes is complicated because they blend in the rich features of the…