J/A+A/700/A222 Gl 410 radial velocity curves (Carmona+, 2025)
Characterizing planetary systems with SPIRou:
Detection of a sub-Neptune in a 6-day period orbit around the M dwarf Gl 410.
Carmona A., Delfosse X., Ould-Elhkim M., Cortes-Zuleta P., Hara N.C.,
Artigau E., Moutou C., Petit A.C., Mignon L., Donati J.F., Cook N.J.,
Gagne J., Forveille T., Diaz R.F., Martioli E., Arnold L., Cadieux C.,
Boisse I., Morin J., Petit P., Fouque P., Bonfils X., Hebrard G., Acuna L.,
do Nascimento J.-D., Jr., Cloutier R., Astudillo-Defru N., Bouchy F.,
Bourrier V., Dalal S., Deleuil M., Doyon R., Dumusque X., Grouffal S.,
Heidari N., Hoyer S., Larue P., Kiefer F., Santerne A., Segransan D.,
Serrano Bell J., Stalport M., Sulis S., Udry S., Vivien H.G.
<Astron. Astrophys. 700, A222 (2025)>
=2025A&A...700A.222C 2025A&A...700A.222C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Stars, M-type ; Exoplanets ;
Radial velocities ; Optical
Keywords: methods: observational - techniques: radial velocities -
techniques: spectroscopic - planets and satellites: detection -
planetary systems -
Abstract:
The search for exoplanets around nearby M dwarfs represents a crucial
milestone in the census of planetary systems in the vicinity of our
Solar System.
Since 2018 our team has been conducting a blind search program for
planets around nearby M dwarfs with the near-IR spectro-polarimeter
and velocimeter SPIRou at the Canada-France-Hawaii Telescope and with
the optical velocimeter SOPHIE at the Haute-Provence Observatory in
France. The aim of this paper is to present our results on Gl 410, a
0.55M☉ 480±150Myr old active M dwarf distant 12pc.
We searched for planetary companions using radial velocities (RVs). We
used the line-by-line (LBL) technique to measure the RVs with SPIRou
and the template matching method with SOPHIE. Three different methods
were employed, two based on principal component analysis (PCA), to
clean the SPIRou RVs for systematics. We applied Gaussian processes
(GP) modeling to correct the SOPHIE RVs for stellar activity. The l1
and apodized sine periodogram analysis was used to search for
planetary signals in the SPIRou data taking into account activity
indicators. We analyzed TESS data and searched for planetary transits.
We report the detection of a Msin(i)=8.4±1.3M☉ sub-Neptune
planet at a period of 6.020±0.004 days in circular orbit with
SPIRou. The same signal, although with lower significance, was also
retrieved in the SOPHIE RV data after correction for activity using a
GP trained on SPIRou's longitudinal magnetic field (Bl) measurements.
The TESS data indicate that the planet is not transiting. Within the
SPIRou wPCA RVs, we find tentative evidence for two additional
planetary signals at 2.99 and 18.7 days.
Infrared RVs are a powerful method to detect extrasolar planets around
active M dwarfs. Care should be taken, however, to correct or filter
systematics generated by residuals of the telluric correction or small
structures in the detector plane. The LBL technique combined with PCA
offers a promising way to reach this objective. Further monitoring of
Gl 410 is necessary.
Description:
Radial velocity measurements of the M dwarf Gl 410 obtained with the
near-IR spectrograph SPIRou at Canada France Hawaii Telescope (from
2020 to 2023) and the optical spectrograph SOPHIE at the Observatoire
de Haute Provence (from 2010 to 2012 and from 2021 to 2023).
In addition to the SPIRou and SOPHIE RV data, the measurements of
activity indicators obtained with SPIRou using LBL (e.g., d2v, d3v,
dLW, dTEMP) are included.
Objects:
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RA (2000) DE Designation(s)
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11 02 38.34 +21 58 01.7 Gl 410 = HD 95650
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 47 127 SOPHIE RV measurements of Gl 410
table3.dat 83 137 SPIRou LBL and Wapiti RV measurements of Gl 410
table5.dat 116 157 SPIRou LBL wPCA RV measurements of Gl 410
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "date" Date Date in YYYY-MM-DD
12- 21 F10.4 d RJD Reduced Julian date (JD-2400000)
23- 30 F8.4 km/s RV Radial velocity
32- 37 F6.4 km/s e_RV Error in RV
39- 43 F5.1 m/s deltaRV RV minus median RV
45- 47 F3.1 m/s e_deltaRV Error in deltaRV
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "date" Date Date in YYYY-MM-DD
12- 22 F11.5 d RJD Reduced Julian date (JD-2400000)
24- 29 F6.2 km/s Vtot Systemic velocity - BERV
31- 38 F8.4 km/s RV-LBL LBL radial velocity
40- 45 F6.4 km/s e_RV-LBL Error in the LBL RV
47- 52 F6.2 m/s deltaRV-LBL LBL RV minus median LBL RV
54- 56 F3.1 m/s e_deltaRV-LBL Error in delta LBL RV
58- 65 F8.4 km/s RV-Wapiti ?=- Wapiti radial velocity
67- 72 F6.4 km/s e_RV-Wapiti ?=- Error in the Wapiti RV
74- 79 F6.2 m/s deltaRV-Wapiti ?=- Wapiti RV minus median Wapiti RV
81- 83 F3.1 m/s e_deltaRV-Wapiti ?=- Error in delta Wapiti RV
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "date" DATE Date in YYYY-MM-DD
12- 22 F11.5 d RJD Reduced Julian date
24- 31 F8.4 km/s RV-WPCA WPCA LBL radial velocity
33- 38 F6.4 km/s e_RV-WPCA Error in the WPCA LBL RV
40- 45 F6.2 m/s deltaRV-WPCA WPCA LBL RV minus median WPCA LBL RV
47- 49 F3.1 m/s e_deltaRV-WPCA Error in delta WPCA LBL RV
51- 58 F8.1 m2/s2 d2v LBL projection onto the 2nd derivative
of the spectrum
60- 65 F6.1 m2/s2 e_d2v Error in d2v
67- 77 F11.1 m3/s3 d3v LBL projection onto the 3rd derivative
of the spectrum
79- 88 F10.1 m3/s3 e_d3v Error in d3v
90- 98 F9.1 m/s dLW LBL differential line width
100-106 F7.1 m/s e_dLW Error in dW
108-112 F5.1 K dT4000 LBL differential temperature with respect
to a T=4000K template
114-116 F3.1 K e_dT4000 Error in dT4000
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Acknowledgements:
Andres Carmora, andres.carmona-gonzalez(at)univ-tlse3.fr
(End) Patricia Vannier [CDS] 23-Jul-2025