J/A+A/678/A207 SPIRou GJ 876 and GJ 1148 RV curves (Moutou+, 2023)
Characterizing planetary systems with SPIRou:
M-dwarf planet-search survey and the multi-planet systems of GJ 876 and GJ 1148.
Moutou C., Delfosse X., Petit A.C., Donati J.F., Artigau E., Fouque P.,
Carmona A., Ould-Elhkim M., Arnold L., Cook NJ., Cadieux C., Bellotti S.,
Boisse I., Bouchy F., Charpentier P., Cortes-Zuleta P., Doyon R.,
Hebrard G., Martioli E., Morin J., Vandal T.
<Astron. Astrophys. 678, A207 (2023)>
=2023A&A...678A.207M 2023A&A...678A.207M (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Stars, M-type ; Exoplanets ;
Radial velocities ; Optical
Keywords: stars: low-mass - planetary systems - methods: observational -
techniques: radial velocities - techniques: polarimetric -
stars: magnetic field
Abstract:
SPIRou is a near-infrared spectropolarimeter and a high-precision
velocimeter. The SPIRou Legacy Survey collected data from February
2019 to June 2022, half of the time devoted to a blind search for
exoplanets around nearby cool stars. The aim of this paper is to
present this program and an overview of its properties, and to revisit
the radial velocity (RV) data of two multiplanet systems, including
new visits with SPIRou. From SPIRou data, we can extract precise RVs
using efficient telluric correction and line-by-line measurement
techniques, and we can reconstruct stellar magnetic fields from the
collection of polarized spectra using the Zeeman- Doppler imaging
method. The stellar sample of our blind search in the solar
neighborhood, the observing strategy, the RV noise estimates,
chromatic behavior, and current limitations of SPIRou RV measurements
on bright M dwarfs are described. In addition, SPIRou data over a
2.5-year time span allow us to revisit the known multiplanet systems
GJ 876 and GJ 1148. For GJ 876, the new dynamical analysis including
the four planets is consistent with previous models and confirms that
this system is deep in the Laplace resonance and likely chaotic. The
large-scale magnetic map of GJ 876 over two consecutive observing
seasons is obtained and shows a dominant dipolar field with a polar
strength of 30G, which defines the magnetic environment in which the
inner planet with a period of 1.94 d is embedded. For GJ 1148, we
refine the known two-planet model.
Description:
Radial velocities of GJ1148 and GJ 876.
Objects:
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RA (2000) DE Designation(s)
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11 41 44.63 +42 45 07.1 GJ 1148 = HIP 57050
22 53 16.73 -14 15 49.3 GJ 876 = HIP 113020
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
gj876.dat 44 88 GJ 876 radial velocity curve
gj1148.dat 45 104 GJ 1148 radial velocity curve
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Byte-by-byte Description of file: gj876.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Name Star name
8- 27 F20.12 d BJD Barycentric Julian date
29- 38 F10.4 m/s RV Radial velocity
40- 45 F6.4 m/s e_RV rms uncertainty on RV
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Byte-by-byte Description of file: gj1148.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 A6 --- Name Star name
8- 27 F20.12 d BJD Barycentric Julian date
29- 38 F10.4 m/s RV Relative radial velocity
40- 45 F6.4 m/s e_RV rms uncertainty on RV
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Acknowledgements:
Claire Mouton, claire.moutou(at)irap.omp.eu
(End) Patricia Vannier [CDS] 07-Oct-2023