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تسجيل مستخدم جديدTemplate RR Lyrae H alpha, H beta, and H gamma Velocity Curves
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Branimir Sesar
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We present template radial velocity curves of $ab$-type RR Lyrae stars constructed from high-precision measurements of ${rm Halpha}$, ${rm Hbeta}$, and ${rm Hgamma}$ lines. Amplitude correlations between the Balmer line velocity curves, Johnson $V$-band, and SDSS $g$- and $r$-band light curves are also derived. Compared to previous methods, these templates and derived correlations reduce the uncertainty in measured systemic (center-of-mass) velocities of RR Lyrae stars by up to 15 {kms}, and will be of particular interest to wide-area spectroscopic surveys such as the Sloan Digital Sky Survey (SDSS) and LAMOST Experiment for Galactic Understanding and Exploration (LEGUE).
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