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arXiv · 2207.09160

ANDICAM I and J band monitoring of bright inner Galactic late-type stars

Maria Messineo
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Abstract

Time-series photometry in I and J band of 57 inner Galactic late-type stars, highly-probable red supergiant (RSG) stars, is here presented. 38% of the sample presents significant photometric variations. The variations in I and J band appear to be correlated, with DeltaI = DeltaJ x 2.2, DeltaI variations ranging from 0.04-1.08 mag, DeltaJ variations from 0.03-0.52 mag. New short periods (< 1000 d) could be estimated for 8 stars and range from 167-433 d. This work confirms that the sample is not contaminated by large-amplitude Asymptotic Giant Branch (AGB) stars. Furthermore, despite the large errors in distance, the period-luminosity diagram suggests that the sample is populating the same sequence as the known Galactic RSGs.

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Maria Messineo. 2022-07-19. ANDICAM I and J band monitoring of bright inner Galactic late-type stars. https://doi.org/10.1093/pasj%2Fpsac055

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