Author ORCID Identifier
Kimberly Ward-Duong: 0000-0002-4479-8291
Document Type
Article
Publication Date
4-10-2025
Publication Title
Astrophysical Journal Letters
Abstract
We present aperture masking interferometry (AMI) observations of the star HIP 65426 at 3.8 μm, as part of the JWST Direct Imaging Early Release Science program, obtained using the Near Infrared Imager and Slitless Spectrograph instrument. This mode provides access to very small inner working angles (even separations slightly below the Michelson limit of 0.5λ/D for an interferometer), which are inaccessible with the classical inner working angles of the JWST coronagraphs. When combined with JWST’s unprecedented infrared sensitivity, this mode has the potential to probe a new portion of parameter space across a wide array of astronomical observations. Using this mode, we are able to achieve a 5σ contrast of ΔmF380M ∼ 7.62 ± 0.13 mag relative to the host star at separations ≳0 . ″ 07, and the contrast deteriorates steeply at separations ≲0 . ″ 07. However, we detect no additional companions interior to the known companion HIP 65426b (at separation ∼0 . ″ 82 or 8 7 − 31 + 108 au ). Our observations thus rule out companions more massive than 10-12 MJup at separations ∼10-20 au from HIP 65426, a region out of reach of ground- or space-based coronagraphic imaging. These observations confirm that the AMI mode on JWST is sensitive to planetary mass companions at close-in separations (≳0 . ″ 07), even for thousands of more distant stars at ∼100 pc, in addition to the stars in the nearby young moving groups and associations, as stated in previous works. This result will allow the planning and successful execution of future observations to probe the inner regions of nearby stellar systems, opening an essentially unexplored parameter space.
Volume
983
Issue
1
DOI
10.3847/2041-8213/adaeb7
ISSN
20418205
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.
Rights
© 2025 The Authors
Recommended Citation
Ray, Shrishmoy; Sallum, Steph; Hinkley, Sasha; Sivaramkrishnan, Anand; Cooper, Rachel; Kammerer, Jens; Greebaum, Alexandra Z.; Thatte, Deeparshi; Stolker, Tomas; Lazzoni, Cecilia; Tokovinin, Andrei; Furio, Matthew de; Factor, Samuel; Meyer, Michael; Stone, Jordan M.; Carter, Aarynn; Biller, Beth; Skemer, Andrew; Suárez, Genaro; Leisenring, Jarron M.; Perrin, Marshall D.; Kraus, Adam L.; Absil, Olivier; Balmer, William O.; Boccaletti, Anthony; Bonavita, Mariangela; Bonnefoy, Mickael; Booth, Mark; Bowler, Brendan P.; Briesemeister, Zackery W.; Bryan, Marta L.; and Calissendorff, Per, "The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems. III. Aperture Masking Interferometric Observations of the Star HIP 65426 at 3.8 μm" (2025). Astronomy: Faculty Publications, Smith College, Northampton, MA.
https://scholarworks.smith.edu/ast_facpubs/138
Comments
Archived as published.