The Feasibility of Directly Imaging Nearby Cold Jovian Planets with MIRI/JWST
Jonathan Brande, Thomas Barclay, Joshua E. Schlieder, Eric D. Lopez, Elisa V. Quintana
(Submitted on 5 Nov 2019)
The upcoming launch of the James Webb Space Telescope (JWST) will dramatically increase our understanding of exoplanets, particularly through direct imaging. Microlensing and radial velocity surveys indicate that some M-dwarfs host long period giant planets. Some of these planets will likely be just a few parsecs away and a few AU from their host stars, a parameter space that cannot be probed by existing high-contrast imagers. We studied whether the coronagraphs on the Mid-Infrared Instrument on JWST can detect Jovian-type planets around nearby M-dwarfs. For a sample of 27 very nearby M-dwarfs, we simulated a sample of Saturn–Jupiter-mass planets with three atmospheric configurations, three orbital separations, observed in three different filters. We found that the f1550c 15.5μm filter is best suited for detecting Jupiter-like planets. Jupiter-like planets with patchy cloud cover, 2 AU from their star, are detectable at 15.5μm around 14 stars in our sample, while Jupiters with clearer atmospheres are detectable around all stars in the sample. Saturns were most detectable at 10.65 and 11.4μm (f1065c and f1140c filters), but only with cloud-free atmospheres and within 3 pc (6 stars). Surveying all 27 stars would take <170 hours of JWST integration time, or just a few hours for a shorter survey of the most favorable targets. There is one potentially detectable known planet in our sample -- GJ~832~b. Observations aimed at detecting this planet should occur in 2024--2026, when the planet is maximally separated from the star.
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:1911.02022 [astro-ph.EP] (or arXiv:1911.02022v1 [astro-ph.EP] for this version)
Submission history
From: Jonathan Brande
[v1] Tue, 5 Nov 2019 19:00:01 UTC (1,450 KB)
