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CCD Observations of the RR Lyrae Variables in the Globular Cluster NGC 5897

Christine M. Clement·Jason F. Rowe
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Abstract

CCD observations for 10 (6 previously known and 4 newly discovered) of the 11 RR Lyrae variables in NGC 5897 have been analysed. The period-luminosity and period-amplitude plots indicate that the population of RR Lyrae variables in NGC 5897 includes 3 fundamental mode, 4 first-overtone and 4 second-overtone variables with mean periods 0.828, 0.459 and 0.343 days respectively. The variables have properties that are similar to some of the Oosterhoff type II variables in Omega Centauri. Two of the new variables (V11 and V13) were previously considered to be possible non-variables that lie within or near the instability strip on the horizontal branch; both have V amplitudes less than 0.2 mag. There is a chance that one or two of the variables (V10 and possibly V3) might be anomalous Cepheids and not RR Lyrae stars.

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Christine M. Clement, Jason F. Rowe. 2001-06-05. CCD Observations of the RR Lyrae Variables in the Globular Cluster NGC 5897. https://doi.org/10.1086/322123

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