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arXiv · 1712.08727

Evidence that the planetary candidate CVSO30c is a background star from optical, seeing-limited data

Chien-Hsiu Lee·Po-Shih Chiang
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Abstract

We report serendipitous optical imaging of CVSO30c, an exoplanet candidate associated with the pre-main sequence T Tauri star CVSO30 resides in the 25 Ori stellar cluster. We perform PSF modeling on our seeing limited optical image to remove the lights from the host star (CVSO30), allowing us to extract photometry of CVSO30c to be g = 23.2+/-0.2 (statistic)+/-0.1 (systematic) and r = 21.5+/-0.1 (statistic)+/-0.1 (systematic) magnitudes, respectively. This is 170 and 80 times too bright in the g and r-band, respectively, if CVSO30c were an L0 substellar object as suggested by previous studies. The optical/infrared colors of CVSO 30c are indicative of a stellar, not substellar object, while the object's color-magnitude diagram position is strikingly inconsistent with expected values for a low mass member of 25 Ori. Broad-band photometry for CVSO30c is instead better fit by contaminants such as a background K3 giant or M subdwarf. Our study demonstrates that optical seeing limited data can help clarify the nature of candidate wide separation planet-mass companions in young star-forming regions.

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Chien-Hsiu Lee, Po-Shih Chiang. 2017-12-23. Evidence that the planetary candidate CVSO30c is a background star from optical, seeing-limited data. https://doi.org/10.3847/2041-8213%2Faaa40b

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