J/AJ/168/104 WASP-69b JWST NIRCam & MIRI eclipse depth sp. (Schlawin+, 2024)
Multiple clues for dayside aerosols and temperature gradients in WASP-69 b from
a Panchromatic JWST Emission Spectrum.
Schlawin E., Mukherjee S., Ohno K., Bell T.J., Beatty T.G., Greene T.P.,
Line M., Challener R.C., Parmentier V., Fortney J.J., Rauscher E.,
Wiser L., Welbanks L., Murphy M., Edelman I., Batalha N., Moran S.E.,
Mehta N., Rieke M.
<Astron. J., 168, 104 (2024)>
=2024AJ....168..104S 2024AJ....168..104S
ADC_Keywords: Exoplanets; Spectra, infrared
Keywords: Exoplanet astronomy ; Exoplanet atmospheres ;
Exoplanet atmospheric composition ; Infrared spectroscopy ;
Chemical enrichment ; James Webb Space Telescope ;
Atmospheric clouds ; Albedo ; Planetary science
Abstract:
WASP-69 b is a hot, inflated, Saturn-mass planet (0.26MJup) with a
zero-albedo equilibrium temperature of 963K. Here, we report the JWST
2-12µm emission spectrum of the planet consisting of two eclipses
observed with NIRCam grism time series and one eclipse observed with
the MIRI low-resolution spectrometer (LRS). The emission spectrum
shows absorption features of water vapor, carbon dioxide, and carbon
monoxide, but no strong evidence for methane. WASP-69 b's emission
spectrum is poorly fit by cloud-free homogeneous models. We find three
possible model scenarios for the planet: (1) a scattering model that
raises the brightness at short wavelengths with a free geometric
albedo parameter; (2) a cloud-layer model that includes high-altitude
silicate aerosols to moderate long-wavelength emission; and (3) a
two-region model that includes significant dayside inhomogeneity and
cloud opacity with two different temperature-pressure profiles. In all
cases, aerosols are needed to fit the spectrum of the planet. The
scattering model requires an unexpectedly high geometric albedo of
0.64. Our atmospheric retrievals indicate inefficient redistribution
of heat and an inhomogeneous dayside distribution, which is
tentatively supported by MIRI LRS broadband eclipse maps that show a
central concentration of brightness. Our more plausible models (2 and
3) retrieve chemical abundances enriched in heavy elements relative to
solar composition by 6x to 14x solar and a C/O ratio of 0.65-0.94,
whereas the less plausible highly reflective scenario (1) retrieves a
slightly lower metallicity and lower C/O ratio.
Description:
WASP-69 b was observed as part of the MIRI And NIRCam Assay for the
Transmission and Emission of Exoplanets (MANATEE) program, which
combines observations from MIRI/LRS 5-14um GTO program 1177 (on
2023-05-02) and NIRCam GTO program 1185 (on 2022-10-25 with F322W2:
2.4-4.01um and on 2023-06-06 with F444W: 3.88-4.98um) to build up
near-infrared to mid-infrared spectra on a wide variety of planets.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
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21 00 06.19 -05 05 40.0 WASP-69 b = NAME Makombe
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File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
sp.dat 79 280 Combined JWST NIRCam & MIRI eclipse depth spectrum
(Data behind Figure 5 - top panel)
spbin.dat 134 79 Rebinned, merged JWST eclipse depth and brightness
temperature spectra (Data behind Figure 5 -
middle and bottom panels)
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See also:
VII/233 : 2MASS All-Sky Extended Source Catalog (XSC) (IPAC/UMass, 2003-2006)
VI/151 : Search for radio emission from giant exoplanets (Griessmeier, 2016)
J/ApJ/683/1076 : Transits of exoplanet XO-3b (Winn+, 2008)
J/MNRAS/445/1114 : WASP-69b, WASP-70Ab and WASP-84b (Anderson+, 2014)
J/A+A/564/A125 : AGN Torus model comparison of AGN in CDFS (Buchner+, 2014)
J/AJ/153/136 : Planets and their host stars with Gaia plx (Stassun+, 2017)
J/ApJ/834/17 : Mass & radius of planets & low mass stars (Chen+, 2017)
J/A+A/608/A135 : Sodium detection in WASP-69b atm. (Casasayas-Barris+, 2017)
J/ApJS/239/14 : Revised exoplanet radii from Gaia DR2 (Johns+, 2018)
J/ApJ/874/L31 : Giant planet bulk and atm. metallicities (Thorngren+, 2019)
J/A+A/630/A135 : Beyond exoplanet mass-radius relations (Ulmer-Moll+, 2019)
J/A+A/641/A158 : GTC transit light curves of WASP-69b (Murgas+, 2020)
J/ApJ/890/23 : NUV and FUV measurements of planet host stars (Loyd+, 2020)
J/AJ/159/278 : He-filter obs. of WASP-69b & WASP-52b (Vissapragada+, 2020)
J/AJ/161/174 : Transit depth biases for 31 planets (Morello+, 2021)
J/ApJS/258/40 : ExoClock project. II. Exoplanet ephemerides (Kokori+, 2022)
J/MNRAS/512/2062 : 10 exoplanet systems transit timing (Basturk+, 2022)
J/A+A/659/L4 : Geometric albedo of HD 209458 b (Brandeker+, 2022)
J/A+A/672/A24 : Geometric albedo of HD 189733b (Krenn+, 2023)
J/AJ/165/104 : Emergent sp. IR fluxes of 122 hot Jupiters (Deming+, 2023)
J/AJ/167/213 : Absolute Calib. IV. Bright star templates (Rieke+, 2024)
J/ApJS/270/14 : Transit times of hot Jupiters from TESS (Wang+, 2024)
Byte-by-byte Description of file: sp.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 F19.16 um lambda [2.45/11.9] Wavelength, spectral element bin
center
21- 26 F6.4 um Width [0.0096/0.25] Wavelength, width of spectral
element
28- 49 E22.16 % Depth [-4.51e-06/0.003] Eclipse depth, fraction
51- 72 E22.16 % e_Depth [3.8e-05/0.0003] Uncertainty in Depth
74- 79 A6 --- Filter Filter or Filters used (1)
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Note (1): Filter as follows:
F322W2 = JWST/NIRCam obs. on 2022-10-25 (2.4-4.01um; 144 occurrences)
F444W = JWST/NIRCam obs. on 2023-06-06 (3.88-4.98um; 102 occurrences)
LRS = JWST/MIRI obs. on 2023-05-02 (5.0-14um; 28 occurrences)
Avg = Average of F322W2 and F444W (6 occurrences)
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Byte-by-byte Description of file: spbin.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 F19.16 um lambda [2/11.9] Wavelength, spectral element bin
center
21- 39 F19.17 um Width [0.049/0.25] Wavelength, width of spectral
element
41- 62 F22.20 --- Depth [0.00013/0.003] Eclipse depth, fraction
64- 85 E22.16 --- e_Depth [2e-05/0.0003] Uncertainty in Depth
87- 96 A10 --- Filter Filter or Filters used (1)
98- 115 F18.13 K Tb [848/1178] Brightness Temperature
117- 134 F18.15 K e_Tb [8.8/66.5] Uncertainty in Tb
--------------------------------------------------------------------------------
Note (1): Filters as follows:
binned NC = (50 occurrences)
LRS = (28 occurrences)
F240M-comb = (1 occurrence)
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 27-Nov-2024