Follow-Up Exploration of the TWA 7 Planet-Disk System with JWST NIRCam

Katie A. Crotts; Aarynn L. Carter; Kellen Lawson; James Mang; Beth Biller; Mark Booth; Rodrigo Ferrer-Chavez; Julien H. Girard; Anne-Marie Lagrange; Michael C. Liu; Sebastian Marino; Maxwell A. Millar-Blanchaer; Andy Skemer; Giovanni M. Strampelli; Jason Wang; Olivier Absil; William O. Balmer; Raphaël Bendahan-West; Ellis Bogat; Rachel Bowens-Rubin; Gaël Chauvin; Clémence Fontanive; Kyle Franson; Jens Kammerer; Jarron Leisenring; Caroline V. Morley; Isabel Rebollido; Nour Skaf; Ben J. Sutlieff; Evelyn L. Bruinsma; Sasha Hinkley; Kielan Hoch; Andrew D. James; Rohan Kane; Dimitri Mawet; Michael R. Meyer; Skyler Palatnick; Marshall D. Perrin; Shrishmoy Ray; Emily Rickman; Aniket Sanghi; Klaus Subbotina Stephenson

arXiv · 2506.19932

Follow-Up Exploration of the TWA 7 Planet-Disk System with JWST NIRCam

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Abstract

The young M-star TWA 7 hosts a bright and near face-on debris disk, which has been imaged from the optical to the submillimeter. The disk displays multiple complex substructures such as three disk components, a large dust clump, and spiral arms, suggesting the presence of planets to actively sculpt these features. The evidence for planets in this disk was further strengthened with the recent detection of a point-source compatible with a Saturn-mass planet companion using JWST/MIRI at 11 $μ$m, at the location a planet was predicted to reside based on the disk morphology. In this paper, we present new observations of the TWA 7 system with JWST/NIRCam in the F200W and F444W filters. The disk is detected at both wavelengths and presents many of the same substructures as previously imaged, although we do not robustly detect the southern spiral arm. Furthermore, we detect two faint potential companions in the F444W filter at the 2-3$σ$ level. While one of these companions needs further followup to determine its nature, the other one coincides with the location of the planet candidate imaged with MIRI, providing further evidence that this source is a sub-Jupiter mass planet companion rather than a background galaxy. Such discoveries make TWA 7 only the second system, after $β$ Pictoris, in which a planet predicted by the debris disk morphology has been detected.

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Katie A. Crotts, Aarynn L. Carter, Kellen Lawson, James Mang, Beth Biller, Mark Booth, Rodrigo Ferrer-Chavez, Julien H. Girard, Anne-Marie Lagrange, Michael C. Liu, Sebastian Marino, Maxwell A. Millar-Blanchaer, Andy Skemer, Giovanni M. Strampelli, Jason Wang, Olivier Absil, William O. Balmer, Raphaël Bendahan-West, Ellis Bogat, Rachel Bowens-Rubin, Gaël Chauvin, Clémence Fontanive, Kyle Franson, Jens Kammerer, Jarron Leisenring, Caroline V. Morley, Isabel Rebollido, Nour Skaf, Ben J. Sutlieff, Evelyn L. Bruinsma, Sasha Hinkley, Kielan Hoch, Andrew D. James, Rohan Kane, Dimitri Mawet, Michael R. Meyer, Skyler Palatnick, Marshall D. Perrin, Shrishmoy Ray, Emily Rickman, Aniket Sanghi, Klaus Subbotina Stephenson. 2025-06-24. Follow-Up Exploration of the TWA 7 Planet-Disk System with JWST NIRCam. https://arxiv.org/abs/2506.19932

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