184 citations · 1k across the 17 of their papers we have counts for
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Detection of Gravity Modes in RR Lyrae Stars
Merieme Chadid
We report the detection of gravity modes in RR Lyrae stars. Thanks to PAIX, the first Antarctica polar photometer. Unprecedented and uninterrupted U BV RI time-series photometric g…
Hydrogen and Helium Shock Phenomena during Rising Light in RR Lyrae Fundamental Mode Pulsators
George W. Preston, Christopher Sneden, Merieme Chadid
We present measurements of H and He emission and absorption lines produced in RRab fundamental mode pulsators during primary light rise. The lines define universal progressions of…
The Axial Rotation and Variable Macroturbulence of RR Lyrae and Red Horizontal Branch Stars
George W. Preston, Christopher Sneden, Merieme Chadid +2
We have derived relations between full-width-half-maxima and equivalent widths of metallic absorption lines in the spectra of RR~Lyrae stars to estimate new upper limits on the axi…
The RRC Stars: Chemical Abundances and Envelope Kinematics
Christopher Sneden, George W. Preston, Merieme Chadid +1
We analyzed series of spectra obtained for twelve stable RRc stars observed with the echelle spectro- graph of the du Pont telescope at Las Campanas Observatory and we analyzed the…
Spectroscopic Comparison of Metal-Rich RRab Stars of the Galactic Field with Their Metal-Poor Counterparts
Merieme Chadid, Christopher Sneden, George W. Preston
We investigate atmospheric properties of 35 stable RRab stars that possess the full ranges of period, light amplitude, and metal abundance found in Galactic RR Lyrae stars. Our res…
Axial rotation and turbulence of RR ab stars: the Peterson Conundrum revisited
G. W. Preston, M. Chadid
We calibrate and then use the relation between equivalent width (EW) and full-width-half-maximum (FWHM) of metallic absorption lines in the spectra of RR Lyrae stars to estimate a…
Metal Abundances, Radial Velocities and other Physical Characteristics for the RR Lyrae Stars in the Kepler Field
James M. Nemec, Judith G. Cohen, Vincenzo Ripepi +5
Spectroscopic iron-to-hydrogen ratios, radial velocities, atmospheric parameters, and new photometric analyses are presented for 41 RR Lyrae stars (and one probable high-amplitude…
Discovery of Peculiar Double-Mode Pulsations and Period Doubling in KEPLER RRc Variables
P. Moskalik, R. Smolec, K. Kolenberg +6
We analyzed the Long Cadence photometry of 4 first overtone RR Lyr-type stars (RRc stars) observed by the KEPLER telescope. All studied variables are multiperiodic. The strongest s…
Period and light curve fluctuations of the Kepler Cepheid V1154 Cyg
A. Derekas, Gy. M. Szabo, L. Berdnikov +11
We present a detailed period analysis of the bright Cepheid-type variable star V1154 Cygni (V =9.1 mag, P~4.9 d) based on almost 600 days of continuous observations by the Kepler s…
Fourier analysis of non-Blazhko ab-type RR Lyrae stars observed with the Kepler space telescope
J. M. Nemec, R. Smolec, J. M. Benko +22
Nineteen of the ~40 RR Lyr stars in the Kepler field have been identified as candidate non-Blazhko (or unmodulated) stars. In this paper we present the results of Fourier decomposi…
Kepler photometry of the prototypical Blazhko star RR Lyr: An old friend seen in a new light
K. Kolenberg, S. Bryson, R. Szabó +18
We present our analysis of the long cadence Kepler data for the well-studied Blazhko star RR Lyr, gathered during the first two quarters of the satellite's observations and coverin…
Does Kepler unveil the mystery of the Blazhko effect? First detection of period doubling in Kepler Blazhko RR Lyrae stars
R. Szabó, Z. Kolláth, L. Molnár +15
The first detection of the period doubling phenomenon is reported in the Kepler RR Lyrae stars RR Lyr, V808 Cyg and V355 Lyr. Interestingly, all these pulsating stars show Blazhko…
CoRoT light curves of RR Lyrae stars. CoRoT 101128793: long-term changes in the Blazhko effect and excitation of additional modes
Ennio Poretti, Margit Paparo, Magali Deleuil +13
The CoRoT (Convection, Rotation and planetary Transits) space mission provides a valuable opportunity to monitor stars with uninterrupted time sampling for up to 150 days at a time…
First Kepler results on RR Lyrae stars
K. Kolenberg, R. Szabó, D. W. Kurtz +21
We present the first results of our analyses of selected RR Lyrae stars for which data have been obtained by the Kepler Mission. As expected, we find a significant fraction of the…