TY - JOUR
T1 - Astrometric Accelerations as Dynamical Beacons: A Giant Planet Imaged inside the Debris Disk of the Young Star AF Lep
AU - Franson, Kyle
AU - Bowler, Brendan P.
AU - Zhou, Yifan
AU - Pearce, Tim D.
AU - Bardalez Gagliuffi, Daniella C.
AU - Biddle, Lauren I.
AU - Brandt, Timothy D.
AU - Crepp, Justin R.
AU - Dupuy, Trent J.
AU - Faherty, Jacqueline
AU - Jensen-Clem, Rebecca
AU - Morgan, Marvin
AU - Sanghi, Aniket
AU - Theissen, Christopher A.
AU - Tran, Quang H.
AU - Wolf, Trevor N.
N1 - Funding Information:
K.F. acknowledges support from the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE 2137420. B.P.B. acknowledges support from the National Science Foundation grant AST-1909209, NASA Exoplanet Research Program grant 20-XRP20_2-0119, and the Alfred P. Sloan Foundation. Y.Z. acknowledges support from the Heising-Simons Foundation 51 Pegasi b Fellowship. T.D.P. is supported by Deutsche Forschungsgemeinschaft (DFG) grants KR 2164/14-2 and KR 2164/15-2. Q.H.T. and B.P.B. acknowledge the support from a NASA FINESST grant (80NSSC20K1554). T.D. acknowledges support from UKRI STFC AGP grant ST/W001209/1. This work was supported by a NASA Keck PI Data Award, administered by the NASA Exoplanet Science Institute. This research has made use of the VizieR catalog access tool, CDS, Strasbourg, France (DOI: 10.26093/cds/vizier). The original description of the VizieR service was published in 2000, A&AS 143, 23. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This work has benefited from The UltracoolSheet at http://bit.ly/UltracoolSheet , maintained by Will Best, Trent Dupuy, Michael Liu, Rob Siverd, and Zhoujian Zhang, and developed from compilations by Dupuy & Liu (), Dupuy & Kraus (), Liu et al. (), Best et al. (), Best et al. ().
Funding Information:
K.F. acknowledges support from the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE 2137420. B.P.B. acknowledges support from the National Science Foundation grant AST-1909209, NASA Exoplanet Research Program grant 20-XRP20_2-0119, and the Alfred P. Sloan Foundation. Y.Z. acknowledges support from the Heising-Simons Foundation 51 Pegasi b Fellowship. T.D.P. is supported by Deutsche Forschungsgemeinschaft (DFG) grants KR 2164/14-2 and KR 2164/15-2. Q.H.T. and B.P.B. acknowledge the support from a NASA FINESST grant (80NSSC20K1554). T.D. acknowledges support from UKRI STFC AGP grant ST/W001209/1. This work was supported by a NASA Keck PI Data Award, administered by the NASA Exoplanet Science Institute. This research has made use of the VizieR catalog access tool, CDS, Strasbourg, France (DOI: 10.26093/cds/vizier). The original description of the VizieR service was published in 2000, A&AS 143, 23. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This work has benefited from The UltracoolSheet at http://bit.ly/UltracoolSheet, maintained by Will Best, Trent Dupuy, Michael Liu, Rob Siverd, and Zhoujian Zhang, and developed from compilations by Dupuy & Liu (2012), Dupuy & Kraus (2013), Liu et al. (2016b), Best et al. (2018), Best et al. (2021).
Publisher Copyright:
© 2023. The Author(s). Published by the American Astronomical Society.
PY - 2023/6/22
Y1 - 2023/6/22
N2 - We present the direct-imaging discovery of a giant planet orbiting the young star AF Lep, a 1.2 M ⊙ member of the 24 ± 3 Myr β Pic moving group. AF Lep was observed as part of our ongoing high-contrast imaging program targeting stars with astrometric accelerations between Hipparcos and Gaia that indicate the presence of substellar companions. Keck/NIRC2 observations in L ′ with the vector vortex coronagraph reveal a point source, AF Lep b, at ≈340 mas, which exhibits orbital motion at the 6σ level over the course of 13 months. A joint orbit fit yields precise constraints on the planet’s dynamical mass of 3.2 − 0.6 + 0.7 M Jup, semimajor axis of 8.4 − 1.3 + 1.1 au, and eccentricity of 0.24 − 0.15 + 0.27 . AF Lep hosts a debris disk located at ∼50 au, but it is unlikely to be sculpted by AF Lep b, implying there may be additional planets in the system at wider separations. The stellar inclination (i * = 54 − 9 + 11 ° ) and orbital inclination (io = 50 − 12 + 9 ° ) are in good agreement, which is consistent with the system having spin-orbit alignment. AF Lep b is the lowest-mass imaged planet with a dynamical mass measurement and highlights the promise of using astrometric accelerations as a tool to find and characterize long-period planets.
AB - We present the direct-imaging discovery of a giant planet orbiting the young star AF Lep, a 1.2 M ⊙ member of the 24 ± 3 Myr β Pic moving group. AF Lep was observed as part of our ongoing high-contrast imaging program targeting stars with astrometric accelerations between Hipparcos and Gaia that indicate the presence of substellar companions. Keck/NIRC2 observations in L ′ with the vector vortex coronagraph reveal a point source, AF Lep b, at ≈340 mas, which exhibits orbital motion at the 6σ level over the course of 13 months. A joint orbit fit yields precise constraints on the planet’s dynamical mass of 3.2 − 0.6 + 0.7 M Jup, semimajor axis of 8.4 − 1.3 + 1.1 au, and eccentricity of 0.24 − 0.15 + 0.27 . AF Lep hosts a debris disk located at ∼50 au, but it is unlikely to be sculpted by AF Lep b, implying there may be additional planets in the system at wider separations. The stellar inclination (i * = 54 − 9 + 11 ° ) and orbital inclination (io = 50 − 12 + 9 ° ) are in good agreement, which is consistent with the system having spin-orbit alignment. AF Lep b is the lowest-mass imaged planet with a dynamical mass measurement and highlights the promise of using astrometric accelerations as a tool to find and characterize long-period planets.
UR - http://www.scopus.com/inward/record.url?scp=85163449114&partnerID=8YFLogxK
U2 - 10.3847/2041-8213/acd6f6
DO - 10.3847/2041-8213/acd6f6
M3 - Article
AN - SCOPUS:85163449114
SN - 2041-8205
VL - 950
SP - 1
EP - 10
JO - Astrophysical Journal Letters
JF - Astrophysical Journal Letters
IS - 2
M1 - L19
ER -