J/A+A/670/A5 GJ1022 radial velocity and FWHM data (Suarez Mascareno+, 2023)
Two temperate Earth-mass planets orbiting the nearby star GJ 1002.
Suarez Mascareno A., Gonzalez-Alvarez E., Zapatero Osorio M.R.,
Lillo-Box J., Faria J.P., Passegger V.M., Gonzalez Hernandez J.I.,
Figueira P., Sozzetti A., Rebolo R., Pepe F., Santos N.C., Cristiani S.,
Lovis C., Silva A.M., Ribas I., Amado P.J., Caballero J.A., Quirrenbach A.,
Reiners A., Zechmeister M., Adibekyan V., Alibert Y., Bejar V.J.S.,
Benatti S., D'Odorico V., Damasso M., Delisle J.-B., Di Marcantonio P.,
Dreizler S., Ehrenreich D., Hatzes A.P., Hara N.C., Henning T., Kaminski A.,
Lopez-Gonzalez M.J., Martins C.J.A.P., Micela G., Montes D., Palle E.,
Pedraz S., Rodriguez E., Rodriguez-Lopez C., Tal-Or L., Sousa S., Udry S.
<Astron. Astrophys. 670, A5 (2023)>
=2023A&A...670A...5S 2023A&A...670A...5S (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Radial velocities ;
Optical
Keywords: techniques: spectroscopy - techniques: radial velocities -
planets and satellites: terrestrial planets - stars: activity -
stars: low-mass - stars: individual: G J1002
Abstract:
We report the discovery and characterisation of two Earth-mass planets
orbiting in the habitable zone of the nearby M-dwarf GJ 1002 based on
the analysis of the radial-velocity (RV) time series from the ESPRESSO
and CARMENES spectrographs. The host star is the quiet M5.5 V star
GJ 1002 (relatively faint in the optical, V∼13.8mag, but brighter in
the infrared, J∼8.3mag), located at 4.84pc from the Sun. We analyse
139 spectroscopic observations taken between 2017 and 2021. We
performed a joint analysis of the time series of the RV and full-width
half maximum (FWHM) of the cross-correlation function (CCF) to model
the planetary and stellar signals present in the data, applying
Gaussian process regression to deal with the stellar activity.
We detect the signal of two planets orbiting GJ 1002. GJ 1002 b is a
planet with a minimum mass mpsini of 1.08±0.13M☉ with an
orbital period of 10.3465±0.0027 days at a distance of
0.0457±0.0013au from its parent star, receiving an estimated stellar
flux of 0.67F☉. GJ 1002 c is a planet with a minimum mass
mpsini of 1.36±0.17M☉ with an orbital period of
20.202±0.013 days at a distance of 0.0738±0.0021au from its parent
star, receiving an estimated stellar flux of 0.257F☉. We also
detect the rotation signature of the star, with a period of 126±15
days. We find that there is a correlation between the temperature of
certain optical elements in the spectrographs and changes in the
instrumental profile that can affect the scientific data, showing a
seasonal behaviour that creates spurious signals at periods longer
than ∼200 days.
GJ 1002 is one of the few known nearby systems with planets that could
potentially host habitable environments. The closeness of the host
star to the Sun makes the angular sizes of the orbits of both planets
(∼9.7 mas and ∼15.7mas, respectively) large enough for their
atmosphere to be studied via high-contrast high-resolution
spectroscopy with instruments such as the future spectrograph ANDES
for the ELT or the LIFE mission.
Description:
Radial velocity, FWHM and echelle temperature data of the observations
of GJ 1002 with ESPRESSO and CARMENES.
Objects:
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RA (2000) DE Designation(s)
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00 06 43.19 -07 32 17.0 GJ 1002 = 2MASS J00064325-0732147
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
rvgj1002.dat 120 139 GJ 1022 radial velocity and FWHM data
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Byte-by-byte Description of file: rvgj1002.dat
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Bytes Format Units Label Explanations
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3- 10 F8.3 d Date Observation date, BJD-2450000
16- 20 F5.2 m/s RV1 Raw RV measurements (ΔRV)
26- 30 F5.2 m/s RV2 Offset corrected RV measurements (ΔRV)
36- 40 F5.2 m/s RV3 Activity corrected RV measurements
(i.e. planetary variations) (ΔRV)
46- 50 F5.2 m/s RV4 Residuals after the fit
(GP+2 planet model, circular) (ΔRV)
57- 60 F4.2 m/s e_RV RV internal uncertainties
65- 70 F6.2 m/s FWHM1 Raw FWHM measurements (ΔFWHM)
75- 80 F6.2 m/s FWHM2 Raw FWHM measurements (ΔFWHM)
85- 90 F6.2 m/s FWHM3 Temperature corrected FWHM measurements
(ΔFWHM)
96-100 F5.2 m/s e_FWHM FWHM internal uncertainties
108-110 I3 mK Temp Echelle grating temperature
120 I1 --- Inst [0/3] Instrument (1)
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Note (1): Instruments as follows:
0 = CARMENES
1 = ESPRESSO 18
2 = ESPRESSO 19
3 = ESPRESSO 21
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Acknowledgements:
Alejandro Suarez Mascareno, asm(at)iac.es
(End) Patricia Vannier [CDS] 15-Dec-2022