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arXiv · 2206.14632

Discovery of a Short Period Pulsator from Istanbul University Observatory

Mustafa Turan Sağlam·Meryem Çördük·Sinan Aliş·Görkem Özgül·Olcaytuğ Özgüllü·Fatih Erkam Göktürk·Rahmi Gündüz·Süleyman Fişek·F. Korhan Yelkenci·Eyüp Kaan Ülgen·Tolga Güver
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Abstract

We report the discovery of a new short period pulsating variable in the field of exoplanet host star XO-2. Variable has been identified while it was being used as a comparison star. In order to verify the variability of the candidate, a follow-up program was carried out. Period analysis of multi-band light curves revealed a very prominent and consistent pulsation periodicity of $P\sim0.95$ hours. Given the variability period, amplitude and the color index, the object is most likely a \emph{Delta Scuti} type variable. Absolute magnitude ($M_{v}$) and the color index $(B-V)_{0}$ of the star determined as $2.76$ and $0.22$, respectively. This $(B-V)_{0}$ of the star corresponds to A7 spectral type with an approximate effective temperature of 7725 K. Machine-learning analysis of the time-series data also revealed that the object is of variable type DSCT with a probability of 78\%.

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Mustafa Turan Sağlam, Meryem Çördük, Sinan Aliş, Görkem Özgül, Olcaytuğ Özgüllü, Fatih Erkam Göktürk, Rahmi Gündüz, Süleyman Fişek, F. Korhan Yelkenci, Eyüp Kaan Ülgen, Tolga Güver. 2022-06-29. Discovery of a Short Period Pulsator from Istanbul University Observatory. https://doi.org/10.55064/tjaa.1103590

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