The Hubble Space Telescope PanCET Program: An Optical to Infrared Transmission Spectrum of HAT-P-32Ab

Journal Article · Wed Jul 01 04:00:00 EDT 2020 · The Astronomical Journal (Online)

DOI:https://doi.org/10.3847/1538-3881/AB96CB· OSTI ID:23013282

Alam, Munazza K.; López-Morales, Mercedes ^[1]; Nikolov, Nikolay ^[2]; Sing, David K. ^[3]; Henry, Gregory W.; Williamson, Michael H. ^[4]; Baxter, Claire; Désert, Jean-Michel ^[5]; Barstow, Joanna K. ^[6]; Mikal-Evans, Thomas ^[7]; Bourrier, Vincent ^[8]; Lavvas, Panayotis ^[9]; Wakeford, Hannah R. ^[10]; Sanz-Forcada, Jorge ^[11]; Buchhave, Lars A. ^[12]; Cohen, Ofer ^[13]; others, and

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1. Center for Astrophysics, Harvard & Smithsonian, 60 Garden Street, Cambridge, MA 01238 (United States)
2. Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States)
3. Department of Physics & Astronomy, Johns Hopkins University, Baltimore, MD 21218 (United States)
4. Center of Excellence in Information Systems, Tennessee State University, Nashville, TN 37209 (United States)
5. Anton Pannekoek Institute for Astronomy, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands)
6. School of Physical Sciences, The Open University, Walton Hall, Milton Keynes, MK7 6AA (United Kingdom)
7. Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)
8. Observatoire de l’Université de Genève, Sauverny (Switzerland)
9. Groupe de Spectrométrie Moleculaire et Atmosphérique, Université de Reims Champagne Ardenne, Reims (France)
10. School of Physics, University of Bristol, HH Wills Physics Laboratory, Tyndall Avenue, Bristol BS8 1TL (United Kingdom)
11. Centro de Astrobiología (CSIC-INTA), ESAC Campus, Villanueva de la Cañada, Madrid (Spain)
12. DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 328, DK-2800 Kgs. Lyngby (Denmark)
13. Lowell Center for Space Science and Technology, University of Massachusetts, Lowell, MA 01854 (United States)

We present a 0.3−5 μm transmission spectrum of the hot Jupiter HAT-P-32Ab observed with the Space Telescope Imaging Spectrograph and Wide Field Camera 3 instruments mounted on the Hubble Space Telescope, combined with Spitzer Infrared Array Camera photometry. The spectrum is composed of 51 spectrophotometric bins with widths ranging between 150 and 400 Å, measured to a median precision of 215 ppm. Comparisons of the observed transmission spectrum to a grid of 1D radiative-convective equilibrium models indicate the presence of clouds/hazes, consistent with previous transit observations and secondary eclipse measurements. To provide more robust constraints on the planet’s atmospheric properties, we perform the first full optical to infrared retrieval analysis for this planet. The retrieved spectrum is consistent with a limb temperature of 1248{sub −92}{sup +92} K, a thick cloud deck, enhanced Rayleigh scattering, and ∼10× solar H{sub 2}O abundance. We find log(Z/Z {sub ⊙}) = 2.41{sub −0.07}{sup +0.06}, and compare this measurement with the mass–metallicity relation derived for the solar system.

• OSTI ID: 23013282
• Journal Information: The Astronomical Journal (Online), Journal Name: The Astronomical Journal (Online) Journal Issue: 1 Vol. 160; ISSN 1538-3881
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COMPARATIVE EVALUATIONS
ELEMENT ABUNDANCE
EQUILIBRIUM
LIMBS
MASS
METALLICITY
PHOTOMETRY
PLANETS
RAYLEIGH SCATTERING
SPACE
SPECTRA
SPECTROPHOTOMETRY
TELESCOPES
TRANSMISSION
WATER