The Hubble PanCET Program: A Metal-rich Atmosphere for the Inflated Hot Jupiter HAT-P-41b

Journal Article · Mon Feb 01 04:00:00 EST 2021 · The Astronomical Journal (Online)

DOI:https://doi.org/10.3847/1538-3881/ABC8F4· OSTI ID:23159089

Sheppard, Kyle B.; Deming, Drake; Ih, Jegug ^[1]; Welbanks, Luis; Madhusudhan, Nikku ^[2]; Mandell, Avi M. ^[3]; Nikolov, Nikolay ^[4]; Henry, Gregory W.; Williamson, Michael H. ^[5]; Sing, David K. ^[6]; López-Morales, Mercedes ^[7]; Sanz-Forcada, Jorge ^[8]; Lavvas, Panayotis ^[9]; Ballester, Gilda E. ^[10]; Evans, Thomas M. ^[11]; others, and

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1. Department of Astronomy, University of Maryland at College Park, College Park, MD 20742 (United States)
2. Institute of Astronomy, University of Cambridge, Madingley Road Cambridge CB3 0HA (United Kingdom)
3. Solar System Exploration Division, NASA’s Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
4. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
5. Center of Excellence in Information Systems, Tennessee State University, Nashville, TN 37209 (United States)
6. Department of Physics & Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States)
7. Center for Astrophysics, Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 01238 (United States)
8. Centro de Astrobiología (CSIC-INTA) (Spain)
9. Groupe de Spectrométrie Moleculaire et Atmosphérique, Université de Reims Champagne Ardenne, Reims (France)
10. Lunar & Planetary Laboratory, Department of Planetary Sciences, University of Arizona, Tucson, AZ (United States)
11. Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, 37-241, Cambridge, MA 02139 (United States)

We present a comprehensive analysis of the 0.3–5 μm transit spectrum for the inflated hot Jupiter HAT-P-41b. The planet was observed in transit with Hubble STIS and WFC3 as part of the Hubble Panchromatic Comparative Exoplanet Treasury (PanCET) program, and we combine those data with warm Spitzer transit observations. We extract transit depths from each of the data sets, presenting the STIS transit spectrum (0.29–0.93 μm) for the first time. We retrieve the transit spectrum both with a free-chemistry retrieval suite (AURA) and a complementary chemical equilibrium retrieval suite (PLATON) to constrain the atmospheric properties at the day–night terminator. Both methods provide an excellent fit to the observed spectrum. Both AURA and PLATON retrieve a metal-rich atmosphere for almost all model assumptions (most likely O/H ratio of log{sub 10}Z/Z{sub ⊙}=1.46{sub −0.68}{sup +0.53} and log{sub 10}Z/Z{sub ⊙}=2.33{sub −0.25}{sup +0.23}, respectively); this is driven by a 4.9σ detection of H{sub 2}O as well as evidence of gas absorption in the optical (>2.7σ detection) due to Na, AlO, and/or VO/TiO, though no individual species is strongly detected. Both retrievals determine the transit spectrum to be consistent with a clear atmosphere, with no evidence of haze or high-altitude clouds. Interior modeling constraints on the maximum atmospheric metallicity (log{sub 10}Z/Z{sub ⊙}<1.7) favor the AURA results. The inferred elemental oxygen abundance suggests that HAT-P-41b has one of the most metal-rich atmospheres of any hot Jupiters known to date. Overall, the inferred high metallicity and high inflation make HAT-P-41b an interesting test case for planet formation theories.

• OSTI ID: 23159089
• Journal Information: The Astronomical Journal (Online), Journal Name: The Astronomical Journal (Online) Journal Issue: 2 Vol. 161; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
79 ASTRONOMY AND ASTROPHYSICS
ABSORPTION
CHEMISTRY
COMPUTERIZED SIMULATION
DETECTION
JUPITER PLANET
METALLICITY
METALS
OXYGEN
SPECTRA
TITANIUM OXIDES
VANADIUM OXIDES