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arXiv · 1104.2668

Radial Velocities and Pulsation Ephemerides of 11 Field RR Lyrae Stars

Bi-Qing For·George W. Preston·Christopher Sneden
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Abstract

We present new radial velocities, improved pulsation periods and reference epoch s of 11 field RR Lyrae ab-type variables: AS Vir, BS Aps, CD Vel, DT Hya, RV Oct, TY Gru, UV Oct, V1645 Sgr, WY Ant, XZ Aps and Z Mic. This study is based on high resolution spectra obtained with the echelle spectro graph of the 2.5-m du Pont telescope at Las Campanas Observatory. We obtained ~200 spectra per star (i.e, total of ~2300 spectra) distributed more or less uniformly throughout their pulsation cycles. Radial velocity curves and photometric lightcurves phased to our new ephemerides are presented for all program stars. In a subsequent paper, we will use these spectra to derive stellar atmospheric parameters and chemical compositions throughout the pulsational cycles, based purely on spectroscopic constraints.

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Bi-Qing For, George W. Preston, Christopher Sneden. 2011-04-14. Radial Velocities and Pulsation Ephemerides of 11 Field RR Lyrae Stars. https://doi.org/10.1088/0067-0049/194/2/38

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