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arXiv · 1712.00701

Test of depending frequencies of the variable Stars of OC: NGC 6866

Gireesh C. Joshi
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Abstract

The search of secondary pulsations is carried out to understand the possible relations among the known parameters of variables of the cluster, NGC 6866. These pulsations arise due to the various ongoing physical phenomena of the variables. Moreover, pulsations of the variables are identified through the visual inspection of their frequency-amplitude distributions. A total of 18 variables among the 28 known variables are showing the secondary pulsation modes. Furthermore, these pulsation modes do not occur for PV, EA, EB, Elliptical and semi-regular. In addition, the field variables seem to be the red-component-stars (RCS) for the studied cluster. The smoothness of the frequency-amplitude curves, signal to noise ratio and the significant limits are play major role for deciding the real peak or frequency values. We are not rejected those amplitude peak of parabolic patterns, for which, the amplitude is greater than then significant limit of variables. The weight of pulsation frequencies is given to be 0.5 for non full cyclic variation but the amplitude is greater than significant limit. Similarly, our present analysis does not support the HADS characteristics of previous known HADS stars within stellar cluster NGC 6866. We are also proposed to new correlation between the secondary pulsation modes (depending frequencies) and the absolute magnitude of known variables.

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Gireesh C. Joshi. 2017-12-03. Test of depending frequencies of the variable Stars of OC: NGC 6866. https://arxiv.org/abs/1712.00701

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