The HARPS search for southern extra-solar planets: XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti
Exoplanet surveys have shown that systems with multiple low-mass planets on compact orbits are common. Except for a few cases, however, the masses of these planets are generally unknown. At the very end of the main sequence, host stars have the lowest mass and hence offer the largest reflect motion...
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Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00046361_v605_n_p_AstudilloDefru http://hdl.handle.net/20.500.12110/paper_00046361_v605_n_p_AstudilloDefru |
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paper:paper_00046361_v605_n_p_AstudilloDefru2023-06-08T14:28:21Z The HARPS search for southern extra-solar planets: XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti Planetary systems Stars: individual: YZ Cet Stars: late-type Techniques: radial velocities Extrasolar planets Planets Stars Dynamical model Mean motion resonances Minimum mass Planetary system Radial velocity Stars: individual Stars:late type Techniques: radial velocities Orbits Exoplanet surveys have shown that systems with multiple low-mass planets on compact orbits are common. Except for a few cases, however, the masses of these planets are generally unknown. At the very end of the main sequence, host stars have the lowest mass and hence offer the largest reflect motion for a given planet. In this context, we monitored the low-mass (0.13 M Ȯ ) M dwarf YZ Cet (GJ 54.1, HIP 5643) intensively and obtained radial velocities and stellar-activity indicators derived from spectroscopy and photometry, respectively. We find strong evidence that it is orbited by at least three planets in compact orbits (P Orb = 1.97, 3.06, 4.66 days), with the inner two near a 2:3 mean-motion resonance. The minimum masses are comparable to the mass of Earth (M sin i = 0.75 ± 0.13, 0.98 ± 0.14, and 1.14 ± 0.17 M O± ), and they are also the lowest masses measured by radial velocity so far. We note the possibility for a fourth planet with an even lower mass of M sin i = 0.472 ± 0.096 M O± at P Orb = 1.04 days. An n-body dynamical model is used to place further constraints on the system parameters. At 3.6 parsecs, YZ Cet is the nearest multi-planet system detected to date. © ESO, 2017. 2017 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00046361_v605_n_p_AstudilloDefru http://hdl.handle.net/20.500.12110/paper_00046361_v605_n_p_AstudilloDefru |
institution |
Universidad de Buenos Aires |
institution_str |
I-28 |
repository_str |
R-134 |
collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
topic |
Planetary systems Stars: individual: YZ Cet Stars: late-type Techniques: radial velocities Extrasolar planets Planets Stars Dynamical model Mean motion resonances Minimum mass Planetary system Radial velocity Stars: individual Stars:late type Techniques: radial velocities Orbits |
spellingShingle |
Planetary systems Stars: individual: YZ Cet Stars: late-type Techniques: radial velocities Extrasolar planets Planets Stars Dynamical model Mean motion resonances Minimum mass Planetary system Radial velocity Stars: individual Stars:late type Techniques: radial velocities Orbits The HARPS search for southern extra-solar planets: XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti |
topic_facet |
Planetary systems Stars: individual: YZ Cet Stars: late-type Techniques: radial velocities Extrasolar planets Planets Stars Dynamical model Mean motion resonances Minimum mass Planetary system Radial velocity Stars: individual Stars:late type Techniques: radial velocities Orbits |
description |
Exoplanet surveys have shown that systems with multiple low-mass planets on compact orbits are common. Except for a few cases, however, the masses of these planets are generally unknown. At the very end of the main sequence, host stars have the lowest mass and hence offer the largest reflect motion for a given planet. In this context, we monitored the low-mass (0.13 M Ȯ ) M dwarf YZ Cet (GJ 54.1, HIP 5643) intensively and obtained radial velocities and stellar-activity indicators derived from spectroscopy and photometry, respectively. We find strong evidence that it is orbited by at least three planets in compact orbits (P Orb = 1.97, 3.06, 4.66 days), with the inner two near a 2:3 mean-motion resonance. The minimum masses are comparable to the mass of Earth (M sin i = 0.75 ± 0.13, 0.98 ± 0.14, and 1.14 ± 0.17 M O± ), and they are also the lowest masses measured by radial velocity so far. We note the possibility for a fourth planet with an even lower mass of M sin i = 0.472 ± 0.096 M O± at P Orb = 1.04 days. An n-body dynamical model is used to place further constraints on the system parameters. At 3.6 parsecs, YZ Cet is the nearest multi-planet system detected to date. © ESO, 2017. |
title |
The HARPS search for southern extra-solar planets: XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti |
title_short |
The HARPS search for southern extra-solar planets: XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti |
title_full |
The HARPS search for southern extra-solar planets: XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti |
title_fullStr |
The HARPS search for southern extra-solar planets: XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti |
title_full_unstemmed |
The HARPS search for southern extra-solar planets: XLII. A system of Earth-mass planets around the nearby M dwarf YZ Ceti |
title_sort |
harps search for southern extra-solar planets: xlii. a system of earth-mass planets around the nearby m dwarf yz ceti |
publishDate |
2017 |
url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00046361_v605_n_p_AstudilloDefru http://hdl.handle.net/20.500.12110/paper_00046361_v605_n_p_AstudilloDefru |
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1768542484601765888 |