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arXiv · 2507.22023

Lightcurves of stars in the Chamaeleon I Association

K. Neumannová·L. Kueß·E. Paunzen·K. Bernhard
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Abstract

Star-forming regions are essential for studying very young stellar objects of various masses. They still contain a significant amount of dust and gas. We present a study of light curves of stars in the field of the Chamaeleon I association. We use automatic spectral classification with MKCLASS to identify the spectral types of the stars in the field with a light curve from the NEOWISE and Gaia surveys. The light curves are analysed using the software Peranso and astropy. We also used VSX to identify the variability type. Based on astrometry, we have identified 92 stars, 73 of which are members of the association. We received light curves for 55 stars from the Gaia survey and for 69 stars from the ALLWISE/NEOWISE survey. For 28 of them, it was possible to determine the types of variables, mostly T Tauri and Orion variables. The spectral types of the members are mostly cooler M-type stars, with one being a possible chemically peculiar (CP) star. The non-members associated with light curve measurements include spectral types A-G with one CP candidate.

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K. Neumannová, L. Kueß, E. Paunzen, K. Bernhard. 2025-07-29. Lightcurves of stars in the Chamaeleon I Association. https://arxiv.org/abs/2507.22023

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