2019/11/05 by Jonathan Brande, Thomas Barclay, Joshua E. Schlieder +2 · 1 citation
Physics and Astronomy · #Astro and Planetary Science #Astronomy and Astrophysical Research #Exoplanet #Gas giant #Gravitational microlensing #Hot Jupiter #Jovian #Planet #Planetary system #Stars #Stellar, planetary, and galactic studies #astro-ph.EP #astro-ph.SR
paper · pdf · doi:10.3847/1538-3881/ab5444
arxiv created 2019/11/05 · openalex created_date 2019/11/22 · openalex publication_date 2019/12/13 · arxiv updated 2020/01/08 · openalex updated_date 2026/08/05
Abstract 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 astronomical units 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 and three orbital separations, observed in three different filters. We found that the f1550c 15.5 μ m filter is best suited for detecting Jupiter-like planets. Jupiter-like planets with patchy cloud cover, 2 au from their star, are detectable at 15.5 μ m 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 11.4 μ m (f1065c and f1140c filters), but only with cloud-free atmospheres and within 3 pc (six stars). Surveying all 27 stars would take <170 hr 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.