Search

Your search keyword '"Bryant, Edward M"' showing total 2 results
Start Over Author "Bryant, Edward M" Publication Type Magazines
2 results on '"Bryant, Edward M"'

1. Early Release Science of the exoplanet WASP-39b with JWST NIRCam

Author

Ahrer, Eva-Maria, Stevenson, Kevin B., Mansfield, Megan, Moran, Sarah E., Brande, Jonathan, Morello, Giuseppe, Murray, Catriona A., Nikolov, Nikolay K., Petit dit de la Roche, Dominique J. M., Schlawin, Everett, Wheatley, Peter J., Zieba, Sebastian, Batalha, Natasha E., Damiano, Mario, Goyal, Jayesh M., Lendl, Monika, Lothringer, Joshua D., Mukherjee, Sagnick, Ohno, Kazumasa, Batalha, Natalie M., Battley, Matthew P., Bean, Jacob L., Beatty, Thomas G., Benneke, Björn, Berta-Thompson, Zachory K., Carter, Aarynn L., Cubillos, Patricio E., Daylan, Tansu, Espinoza, Néstor, Gao, Peter, Gibson, Neale P., Gill, Samuel, Harrington, Joseph, Hu, Renyu, Kreidberg, Laura, Lewis, Nikole K., Line, Michael R., López-Morales, Mercedes, Parmentier, Vivien, Powell, Diana K., Sing, David K., Tsai, Shang-Min, Wakeford, Hannah R., Welbanks, Luis, Alam, Munazza K., Alderson, Lili, Allen, Natalie H., Anderson, David R., Barstow, Joanna K., Bayliss, Daniel, Bell, Taylor J., Blecic, Jasmina, Bryant, Edward M., Burleigh, Matthew R., Carone, Ludmila, Casewell, S. L., Changeat, Quentin, Chubb, Katy L., Crossfield, Ian J. M., Crouzet, Nicolas, Decin, Leen, Désert, Jean-Michel, Feinstein, Adina D., Flagg, Laura, Fortney, Jonathan J., Gizis, John E., Heng, Kevin, Iro, Nicolas, Kempton, Eliza M.-R., Kendrew, Sarah, Kirk, James, Knutson, Heather A., Komacek, Thaddeus D., Lagage, Pierre-Olivier, Leconte, Jérémy, Lustig-Yaeger, Jacob, MacDonald, Ryan J., Mancini, Luigi, May, E. M., Mayne, N. J., Miguel, Yamila, Mikal-Evans, Thomas, Molaverdikhani, Karan, Palle, Enric, Piaulet, Caroline, Rackham, Benjamin V., Redfield, Seth, Rogers, Laura K., Roy, Pierre-Alexis, Rustamkulov, Zafar, Shkolnik, Evgenya L., Sotzen, Kristin S., Taylor, Jake, Tremblin, P., Tucker, Gregory S., Turner, Jake D., de Val-Borro, Miguel, Venot, Olivia, and Zhang, Xi

Abstract

Measuring the metallicity and carbon-to-oxygen (C/O) ratio in exoplanet atmospheres is a fundamental step towards constraining the dominant chemical processes at work and, if in equilibrium, revealing planet formation histories. Transmission spectroscopy (for example, refs. 1,2) provides the necessary means by constraining the abundances of oxygen- and carbon-bearing species; however, this requires broad wavelength coverage, moderate spectral resolution and high precision, which, together, are not achievable with previous observatories. Now that JWST has commenced science operations, we are able to observe exoplanets at previously uncharted wavelengths and spectral resolutions. Here we report time-series observations of the transiting exoplanet WASP-39b using JWST’s Near InfraRed Camera (NIRCam). The long-wavelength spectroscopic and short-wavelength photometric light curves span 2.0–4.0 micrometres, exhibit minimal systematics and reveal well defined molecular absorption features in the planet’s spectrum. Specifically, we detect gaseous water in the atmosphere and place an upper limit on the abundance of methane. The otherwise prominent carbon dioxide feature at 2.8 micrometres is largely masked by water. The best-fit chemical equilibrium models favour an atmospheric metallicity of 1–100-times solar (that is, an enrichment of elements heavier than helium relative to the Sun) and a substellar C/O ratio. The inferred high metallicity and low C/O ratio may indicate significant accretion of solid materials during planet formation (for example, refs. 3,4,) or disequilibrium processes in the upper atmosphere (for example, refs. 5,6).

Published
2023
Full Text
View/download PDF

2. A remnant planetary core in the hot-Neptune desert

Author

Armstrong, David J., Lopez, Théo A., Adibekyan, Vardan, Booth, Richard A., Bryant, Edward M., Collins, Karen A., Deleuil, Magali, Emsenhuber, Alexandre, Huang, Chelsea X., King, George W., Lillo-Box, Jorge, Lissauer, Jack J., Matthews, Elisabeth, Mousis, Olivier, Nielsen, Louise D., Osborn, Hugh, Otegi, Jon, Santos, Nuno C., Sousa, Sérgio G., Stassun, Keivan G., Veras, Dimitri, Ziegler, Carl, Acton, Jack S., Almenara, Jose M., Anderson, David R., Barrado, David, Barros, Susana C. C., Bayliss, Daniel, Belardi, Claudia, Bouchy, Francois, Briceño, César, Brogi, Matteo, Brown, David J. A., Burleigh, Matthew R., Casewell, Sarah L., Chaushev, Alexander, Ciardi, David R., Collins, Kevin I., Colón, Knicole D., Cooke, Benjamin F., Crossfield, Ian J. M., Díaz, Rodrigo F., Mena, Elisa Delgado, Demangeon, Olivier D. S., Dorn, Caroline, Dumusque, Xavier, Eigmüller, Philipp, Fausnaugh, Michael, Figueira, Pedro, Gan, Tianjun, Gandhi, Siddharth, Gill, Samuel, Gonzales, Erica J., Goad, Michael R., Günther, Maximilian N., Helled, Ravit, Hojjatpanah, Saeed, Howell, Steve B., Jackman, James, Jenkins, James S., Jenkins, Jon M., Jensen, Eric L. N., Kennedy, Grant M., Latham, David W., Law, Nicholas, Lendl, Monika, Lozovsky, Michael, Mann, Andrew W., Moyano, Maximiliano, McCormac, James, Meru, Farzana, Mordasini, Christoph, Osborn, Ares, Pollacco, Don, Queloz, Didier, Raynard, Liam, Ricker, George R., Rowden, Pamela, Santerne, Alexandre, Schlieder, Joshua E., Seager, Sara, Sha, Lizhou, Tan, Thiam-Guan, Tilbrook, Rosanna H., Ting, Eric, Udry, Stéphane, Vanderspek, Roland, Watson, Christopher A., West, Richard G., Wilson, Paul A., Winn, Joshua N., Wheatley, Peter, Villasenor, Jesus Noel, Vines, Jose I., and Zhan, Zhuchang

Abstract

The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically barren hot-Neptune ‘desert’1,2(a region in mass–radius space that contains few planets) have proved to be particularly valuable in this regard. These planets include HD149026b3, which is thought to have an unusually massive core, and recent discoveries such as LTT9779b4and NGTS-4b5, on which photoevaporation has removed a substantial part of their outer atmospheres. Here we report observations of the planet TOI-849b, which has a radius smaller than Neptune’s but an anomalously large mass of 39.1−2.6+2.7Earth masses and a density of 5.2−0.8+0.7grams per cubic centimetre, similar to Earth’s. Interior-structure models suggest that any gaseous envelope of pure hydrogen and helium consists of no more than 3.9−0.9+0.8per cent of the total planetary mass. The planet could have been a gas giant before undergoing extreme mass loss via thermal self-disruption or giant planet collisions, or it could have avoided substantial gas accretion, perhaps through gap opening or late formation6. Although photoevaporation rates cannot account for the mass loss required to reduce a Jupiter-like gas giant, they can remove a small (a few Earth masses) hydrogen and helium envelope on timescales of several billion years, implying that any remaining atmosphere on TOI-849b is likely to be enriched by water or other volatiles from the planetary interior. We conclude that TOI-849b is the remnant core of a giant planet.

Published
2020
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results