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arXiv · 2512.13254

Non-detection of J1407b in ALMA Band 7 Observations

Pamela Klaassen·Matthew Kenworthy·Eric Mamajek·Nienke van der Marel·Michiel Min·Amaury Triaud·Antonion Hales
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Abstract

We report on ALMA Band 7 continuum observations towards the star 1SWASP J140747.93-394542.6 taken in mid 2024. These observations were a follow-up of a previous detection of an emission source in the J1407 field of view at an unexpected position in 2017. Proper motion analysis indicated that if this were the object responsible for the 2007 eclipse of J1407, it would be detectable at a new position, but still within an ALMA field of view in 2024. Here we present the non-detection of emission in the ALMA field of view (to a 1σ upper limit of 17.5 μJy),at both the 2017 position, and the position expected from proper motions. We place upper limits on a source at the proper motion corrected expected location in this 2024 data, and rule out the possibility of a dusty object being responsible for the 2007 eclipse

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Pamela Klaassen, Matthew Kenworthy, Eric Mamajek, Nienke van der Marel, Michiel Min, Amaury Triaud, Antonion Hales. 2025-12-15. Non-detection of J1407b in ALMA Band 7 Observations. https://doi.org/10.3847/2515-5172%2Fae2680

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