J/AJ/162/290 OSIRIS K-band spectra of planets HR8799 b, c, and d (Ruffio+, 2021)
Deep Exploration of the Planets HR8799 b, c, and d with Moderate-resolution
Spectroscopy.
Ruffio J.-B., Konopacky Q.M., Barman T., Macintosh B., Hoch K.K.W.,
De Rosa R.J., Wang J.J., Czekala I., Marois C.
<Astron. J., 162, 290 (2021)>
=2021AJ....162..290R 2021AJ....162..290R
ADC_Keywords: Exoplanets; Stars, F-type; Spectra, infrared
Keywords: Extrasolar gaseous giant planets ; Exoplanet atmospheric
composition ; Direct imaging ; Exoplanet formation
Abstract:
The four directly imaged planets orbiting the star HR8799 are an ideal
laboratory to probe atmospheric physics and formation models. We
present more than a decade's worth of Keck/OSIRIS observations of
these planets, which represent the most detailed look at their
atmospheres to date by its resolution and signal-to-noise ratio. We
present the first direct detection of HR8799d, the second-closest
known planet to the star, at moderate spectral resolution with
Keck/OSIRIS (K-band; R∼4000). Additionally, we uniformly analyze new
and archival OSIRIS data (H and K band) of HR8799b, c, and d. First,
we show detections of water (H2O) and carbon monoxide (CO) in the
three planets and discuss the ambiguous case of methane (CH4) in the
atmosphere of HR8799b. Then, we report radial-velocity (RV)
measurements for each of the three planets. The RV measurement of
HR8799 d is consistent with predictions made assuming coplanarity and
orbital stability of the HR8799 planetary system. Finally, we perform
a uniform atmospheric analysis on the OSIRIS data, published
photometric points, and low-resolution spectra. We do not infer any
significant deviation from the stellar value of the carbon-to-oxygen
ratio (C/O) of the three planets, which therefore does not yet yield
definitive information about the location or method of formation.
However, constraining the C/O for all the HR8799 planets is a
milestone for any multiplanet system, and particularly important for
large, widely separated gas giants with uncertain formation processes.
Description:
OH-Suppressing Infrared Integral Field Spectrograph (OSIRIS) is an
infrared integral field spectrograph on the W. M. Keck I telescope
with moderate spectral resolution (R∼4000). The smallest platescale
(20mas/pix; ∼1.3"x0.3" field of view) was used for all but the 2018
observations (35mas/pix).
Objects:
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RA (2000) DE Designation(s)
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23 07 28.72 +21 08 03.3 HR 8799 = HD 218396
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig11.dat 89 3316 Extracted spectra of HR 8799b, c, and d
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See also:
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
J/ApJ/761/57 : CHARA array angular diameters of HR 8799 (Baines+, 2012)
J/ApJ/762/88 : Young stellar kinematic group candidate members (Malo+, 2013)
J/A+A/566/A130 : Rotation & variability substellar objects (Crossfield, 2014)
J/MNRAS/440/1649 : ExoMol line lists for CH4 (Yurchenko+, 2014)
J/MNRAS/454/593 : Young moving groups in solar neighbourhood (Bell+, 2015)
J/A+A/587/A57 : HR 8799e and HR 8799d spectra (Zurlo+, 2016)
J/AJ/155/226 : Gemini Planet Imager spectra of HR8799c/d/e (Greenbaum+, 2018)
J/AJ/158/13 : The first 300 stars observed by the GPIES (Nielsen+, 2019)
J/AJ/159/63 : New AO exoplanets & brown dwarf companions (Bowler+, 2020)
J/A+A/633/A110 : K band spectrum of beta Pictoris b (GRAVITY+, 2020)
J/AJ/160/207 : OSIRIS K-band spectroscopy κAndromedaeb (Wilcomb+, 2020)
J/ApJ/891/171 : COCONUTS. I. Spectra of WD & T4 comoving syst. (Zhang+, 2020)
Byte-by-byte Description of file: fig11.dat
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Bytes Format Units Label Explanations
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1- 7 F7.5 um Waveb [1.47/2.39] Planet b wavelength
9- 15 F7.4 --- Fluxb [-0.1/0.09]? Planet b flux; continuum subtracted
17- 22 F6.4 --- e_Fluxb [0.003/0.07]? Uncertainty in Fluxb
24- 29 F6.4 --- Transb [0.29/1.36]? Planet b atmosphere transmission
31- 37 F7.5 um Wavec [1.47/2.39] Planet c wavelength
39- 45 F7.4 --- Fluxc [-0.15/0.13]? Planet c flux; continuum subtracted
47- 52 F6.4 --- e_Fluxc [0.005/0.06]? Uncertainty in Fluxc
54- 59 F6.4 --- Transc [0.25/1.51]? Planet c atmosphere transmission
61- 67 F7.5 um Waved [1.95/2.39]? Planet d wavelength
69- 75 F7.4 --- Fluxd [-0.4/0.29]? Planet d flux; continuum subtracted
77- 82 F6.4 --- e_Fluxd [0.02/0.3]? Uncertainty in Fluxd
84- 89 F6.4 --- Transd [0.28/1.31]? Planet d atmosphere transmission
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 09-Mar-2022