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arXiv · 2409.11266

Colour-Based Disentangling of Mira Variables and Ultra-Cool Dwarfs

Aleksandra Avdeeva·Kefeng Tan·Santosh Joshi·Dana Kovaleva·Harinder P. Singh·Ali Luo·Oleg Malkov
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Abstract

Despite having different astronomical characteristics, the studies of mira variables and ultra-cool dwarfs frequently show similar red colors, which could cause leading to photometric misclassification. This study uses photometric data from the WISE, 2MASS, and Pan-STARRS surveys to construct color-based selection criteria for red dwarfs, brown dwarfs, and Mira variables. On analyzing the color indices, we developed empirical rules that separate these objects with an overall classification accuracy of approximately 91%-92%. While the differentiation between red dwarfs and both Mira variables and brown dwarfs is effective, challenges remain in distinguishing Mira variables from brown dwarfs due to overlapping color indices. The robustness of our classification technique was validated by a bootstrap analysis, highlighting the significance of color indices in large photometric surveys for stellar classification.

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Aleksandra Avdeeva, Kefeng Tan, Santosh Joshi, Dana Kovaleva, Harinder P. Singh, Ali Luo, Oleg Malkov. 2024-09-17. Colour-Based Disentangling of Mira Variables and Ultra-Cool Dwarfs. https://arxiv.org/abs/2409.11266

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