J/ApJ/922/L2 Limits on binary planets in HR 8799b, c & d (Vanderburg+, 2021)
First Doppler limits on binary planets and exomoons in the HR 8799 system.
Vanderburg A., Rodriguez J.E.
<Astrophys. J., 922, L2 (2021)>
=2021ApJ...922L...2V 2021ApJ...922L...2V
ADC_Keywords: Exoplanets; Radial velocities; Spectra, infrared
Keywords: Direct imaging ; Natural satellites (Extrasolar) ;
Exoplanet detection methods
Abstract:
We place the first constraints on binary planets and exomoons from
Doppler monitoring of directly imaged exoplanets. We model radial
velocity observations of HR 8799 b, c, and d from
Ruffio+ (2021, J/AJ/162/290) and determine upper limits on the msini
of short-period binary planets and satellites. At 95% confidence, we
rule out companions orbiting the three planets more massive than
msini=2MJ with orbital periods shorter than 5 days. We achieve our
tightest constraints on moons orbiting HR 8799c, where with 95%
confidence we rule out out edge-on Jupiter-mass companions in periods
shorter than 5 days and edge-on half-Jupiter-mass moons in periods
shorter than 1 day. These radial velocity observations come from
spectra with resolution 20 times lower than typical radial velocity
instruments and were taken using a spectrograph that was designed
before the first directly imaged exoplanet was discovered. Similar
data sets from new and upcoming instruments will probe significantly
lower exomoon masses.
Description:
We use the radial velocity observations of HR 8799 b, c, and d
reported by Ruffio+ (2021, J/AJ/162/290). These observations were made
over the course of a decade (between UT 2010 July 11 and UT 2020
August 3) with the OH-Suppressing Infrared Integral Field Spectrograph
(OSIRIS, R∼4000) on the Keck telescopes. Most of the observations
reported were made in the K band, some were derived from both H and K
bands, and others were made entirely from the H-band observations.
Objects:
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RA (ICRS) DE Designation(s)
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23 07 28.71 +21 08 03.3 HR 8799 b = WDS J23075+2108Ab
23 07 28.71 +21 08 03.3 HR 8799 c = WDS J23075+2108Ac
23 07 28.71 +21 08 03.3 HR 8799 d = WDS J23075+2108Ad
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 40 26 *Radial velocities of HR 8799 b, c, and d
fig2.dat 65 500 Limits on the presence of orbiting companions
to the HR 8799 planets
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Note on table1.dat: These observations are as reported by
Ruffio+ (2021, J/AJ/162/290).
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See also:
J/ApJ/761/57 : CHARA array angular diameters of HR 8799 (Baines+, 2012)
J/ApJ/807/45 : Habitable planets around M dwarfs (Dressing+, 2015)
J/A+A/587/A57 : HR 8799e and HR 8799d spectra (Zurlo+, 2016)
J/AJ/155/226 : Gemini Planet Imager sp. of HR 8799 c/d/e (Greenbaum+, 2018)
J/A+A/633/A110 : K band spectrum of beta Pictoris b (GRAVITY+, 2020)
J/AJ/162/290 : OSIRIS K-band sp. of planets HR8799 b, c & d (Ruffio+, 2021)
J/AJ/164/143 : Sp. of HR 8799 planets with SCExAO/CHARIS (Wang+, 2022)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Planet name
11- 20 F10.2 d BJD Barycentric Julian Date
22- 26 F5.1 km/s RV [-18.3/-3.2] Radial velocity
28- 30 F3.1 km/s e_RV [0.7/3.5] RV uncertainty
32- 36 F5.3 arcsec Scale [0.02/0.035] Pixel scale
38- 40 A3 --- Filt Filter / Band ("H", "K" or "H/K")
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Byte-by-byte Description of file: fig2.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq [0/499] Line number
5- 8 F4.2 d Per [0.01/9.99] Moon orbital period, P
10- 14 F5.3 Mjup 1sigmab [0.097/5.54] The 1σ limits for planet b
16- 20 F5.3 Mjup 2sigmab [0.14/9.83] The 2σ limits for planet b
22- 27 F6.3 Mjup 3sigmab [0.22/11.17] The 3σ limits for planet b
29- 33 F5.3 Mjup 1sigmac [0.057/2.67] The 1σ limits for planet c
35- 39 F5.3 Mjup 2sigmac [0.13/4.98] The 2σ limits for planet c
41- 46 F6.3 Mjup 3sigmac [0.24/12.28] The 3σ limits for planet c
48- 52 F5.3 Mjup 1sigmad [0.075/1.56] The 1σ limits for planet d
54- 58 F5.3 Mjup 2sigmad [0.23/4.7] The 2σ limits for planet d
60- 65 F6.3 Mjup 3sigmad [0.54/59.1] The 3σ limits for planet d
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 31-Mar-2023