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arXiv · 2208.14990

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems I: High Contrast Imaging of the Exoplanet HIP 65426 b from 2-16 $μ$m

Aarynn L. Carter·Sasha Hinkley·Jens Kammerer·Andrew Skemer·Beth A. Biller·Jarron M. Leisenring·Maxwell A. Millar-Blanchaer·Simon Petrus·Jordan M. Stone·Kimberly Ward-Duong·Jason J. Wang·Julien H. Girard·Dean C. Hines·Marshall D. Perrin·Laurent Pueyo·William O. Balmer·Mariangela Bonavita·Mickael Bonnefoy·Gael Chauvin·Elodie Choquet·Valentin Christiaens·Camilla Danielski·Grant M. Kennedy·Elisabeth C. Matthews·Brittany E. Miles·Polychronis Patapis·Shrishmoy Ray·Emily Rickman·Steph Sallum·Karl R. Stapelfeldt·Niall Whiteford·Yifan Zhou·Olivier Absil·Anthony Boccaletti·Mark Booth·Brendan P. Bowler·Christine H. Chen·Thayne Currie·Jonathan J. Fortney·Carol A. Grady·Alexandra Z. Greenbaum·Thomas Henning·Kielan K. W. Hoch·Markus Janson·Paul Kalas·Matthew A. Kenworthy·Pierre Kervella·Adam L. Kraus·Pierre-Olivier Lagage·Michael C. Liu·Bruce Macintosh·Sebastian Marino·Mark S. Marley·Christian Marois·Brenda C. Matthews·Dimitri Mawet·Michael W. McElwain·Stanimir Metchev·Michael R. Meyer·Paul Molliere·Sarah E. Moran·Caroline V. Morley·Sagnick Mukherjee·Eric Pantin·Andreas Quirrenbach·Isabel Rebollido·Bin B. Ren·Glenn Schneider·Malavika Vasist·Kadin Worthen·Mark C. Wyatt·Zackery W. Briesemeister·Marta L. Bryan·Per Calissendorff·Faustine Cantalloube·Gabriele Cugno·Matthew De Furio·Trent J. Dupuy·Samuel M. Factor·Jacqueline K. Faherty·Michael P. Fitzgerald·Kyle Franson·Eileen C. Gonzales·Callie E. Hood·Alex R. Howe·Masayuki Kuzuhara·Anne-Marie Lagrange·Kellen Lawson·Cecilia Lazzoni·Ben W. P. Lew·Pengyu Liu·Jorge Llop-Sayson·James P. Lloyd·Raquel A. Martinez·Johan Mazoyer·Paulina Palma-Bifani·Sascha P. Quanz·Jea Adams Redai·Matthias Samland·Joshua E. Schlieder

Abstract

We present JWST Early Release Science (ERS) coronagraphic observations of the super-Jupiter exoplanet, HIP 65426 b, with the Near-Infrared Camera (NIRCam) from 2-5 $μ$m, and with the Mid-Infrared Instrument (MIRI) from 11-16 $μ$m. At a separation of $\sim$0.82" (86$^{+116}_{-31}$ au), HIP 65426 b is clearly detected in all seven of our observational filters, representing the first images of an exoplanet to be obtained by JWST, and the first ever direct detection of an exoplanet beyond 5 $μ$m. These observations demonstrate that JWST is exceeding its nominal predicted performance by up to a factor of 10, depending on separation and subtraction method, with measured 5$σ$ contrast limits of $\sim$1$\times10^{-5}$ and $\sim$2$\times10^{-4}$ at 1" for NIRCam at 4.4 $μ$m and MIRI at 11.3 $μ$m, respectively. These contrast limits provide sensitivity to sub-Jupiter companions with masses as low as 0.3$M_\mathrm{Jup}$ beyond separations of $\sim$100 au. Together with existing ground-based near-infrared data, the JWST photometry are well fit by a BT-SETTL atmospheric model from 1-16 $μ$m, and span $\sim$97% of HIP 65426 b's luminous range. Independent of the choice of model atmosphere we measure an empirical bolometric luminosity that is tightly constrained between $\mathrm{log}\!\left(L_\mathrm{bol}/L_{\odot}\right)$=-4.31 to $-$4.14, which in turn provides a robust mass constraint of 7.1$\pm$1.2 $M_\mathrm{Jup}$. In totality, these observations confirm that JWST presents a powerful and exciting opportunity to characterise the population of exoplanets amenable to high-contrast imaging in greater detail.

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Aarynn L. Carter, Sasha Hinkley, Jens Kammerer, Andrew Skemer, Beth A. Biller, Jarron M. Leisenring, Maxwell A. Millar-Blanchaer, Simon Petrus, Jordan M. Stone, Kimberly Ward-Duong, Jason J. Wang, Julien H. Girard, Dean C. Hines, Marshall D. Perrin, Laurent Pueyo, William O. Balmer, Mariangela Bonavita, Mickael Bonnefoy, Gael Chauvin, Elodie Choquet, Valentin Christiaens, Camilla Danielski, Grant M. Kennedy, Elisabeth C. Matthews, Brittany E. Miles, Polychronis Patapis, Shrishmoy Ray, Emily Rickman, Steph Sallum, Karl R. Stapelfeldt, Niall Whiteford, Yifan Zhou, Olivier Absil, Anthony Boccaletti, Mark Booth, Brendan P. Bowler, Christine H. Chen, Thayne Currie, Jonathan J. Fortney, Carol A. Grady, Alexandra Z. Greenbaum, Thomas Henning, Kielan K. W. Hoch, Markus Janson, Paul Kalas, Matthew A. Kenworthy, Pierre Kervella, Adam L. Kraus, Pierre-Olivier Lagage, Michael C. Liu, Bruce Macintosh, Sebastian Marino, Mark S. Marley, Christian Marois, Brenda C. Matthews, Dimitri Mawet, Michael W. McElwain, Stanimir Metchev, Michael R. Meyer, Paul Molliere, Sarah E. Moran, Caroline V. Morley, Sagnick Mukherjee, Eric Pantin, Andreas Quirrenbach, Isabel Rebollido, Bin B. Ren, Glenn Schneider, Malavika Vasist, Kadin Worthen, Mark C. Wyatt, Zackery W. Briesemeister, Marta L. Bryan, Per Calissendorff, Faustine Cantalloube, Gabriele Cugno, Matthew De Furio, Trent J. Dupuy, Samuel M. Factor, Jacqueline K. Faherty, Michael P. Fitzgerald, Kyle Franson, Eileen C. Gonzales, Callie E. Hood, Alex R. Howe, Masayuki Kuzuhara, Anne-Marie Lagrange, Kellen Lawson, Cecilia Lazzoni, Ben W. P. Lew, Pengyu Liu, Jorge Llop-Sayson, James P. Lloyd, Raquel A. Martinez, Johan Mazoyer, Paulina Palma-Bifani, Sascha P. Quanz, Jea Adams Redai, Matthias Samland, Joshua E. Schlieder. 2023-05-03. The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems I: High Contrast Imaging of the Exoplanet HIP 65426 b from 2-16 $μ$m. https://doi.org/10.3847/2041-8213%2Facd93e

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