Non-detection of J1407b in ALMA Band 7 Observations

TL;DR

This study used ALMA Band 7 observations to search for emission from the hypothesized object J1407b associated with the 2007 eclipse of star J1407, but found no detectable emission, constraining its nature.

Contribution

The paper provides the first ALMA non-detection of J1407b, setting upper limits on its emission and ruling out a dusty object as the cause of the 2007 eclipse.

Findings

No emission detected at the 2017 or expected 2024 positions.

Upper limit of 17.5 μJy on emission at the target location.

Rules out dusty object hypothesis for the 2007 eclipse.

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 1{\sigma} upper limit of 17.5 {\mu}Jy),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