J/A+A/680/A28 GJ 724 and GJ 3988 RV timeseries (Gorrini+, 2023)
Planetary companions orbiting the M dwarfs GJ 724 and GJ 3988.
A CARMENES and IRD collaboration.
Gorrini P., Kemmer J., Dreizler S., Burn R., Hirano T., Pozuelos F.J.,
Kuzuhara M., Caballero J.A., Amado P.J., Harakawa H., Kudo T.,
Quirrenbach A., Reiners A., Ribas I., Bejar V.J.S., Chaturvedi P.,
Cifuentes C., Galadi-Enriquez D., Hatzes A.P., Kaminski A., Kotani T.,
Kuerster M., Livingston J.H., Lopez Gonzalez M.J., Montes D., Morales J.C.,
Murgas F., Omiya M., Palle E., Rodriguez E., Sato B., Schweitzer A.,
Shan Y., Takarada T., Tal-Or L., Tamura M., Vievard S.,
Zapatero Osorio M.R., Zechmeister M.
<Astron. Astrophys. 680, A28 (2023)>
=2023A&A...680A..28G 2023A&A...680A..28G (SIMBAD/NED BibCode)
ADC_Keywords: Stars, late-type ; Stars, M-type ; Exoplanets ;
Radial velocities ; Optical
Keywords: techniques: radial velocities - stars: individual: GJ 724, GJ 3988 -
stars: late-type - planets and satellites: detection
Abstract:
We report the discovery of two exoplanets around the M dwarfs GJ 724
and GJ 3988 using the radial velocity (RV) method. We obtained a total
of 153 3.5m Calar Alto/CARMENES spectra for both targets and measured
their RVs and activity indicators. We also added archival ESO/HARPS
data for GJ 724 and infrared RV measurements from Subaru/IRD for
GJ 3988. We searched for periodic and stable signals to subsequently
construct Keplerian models, considering different numbers of planets,
and we selected the best models based on their Bayesian evidence.
Gaussian process (GP) regression was included in some models to
account for activity signals. For both systems, the best model
corresponds to one single planet. The minimum masses are
10.75+0.96-0.87 and 3.69+0.42_-0.41^ Earth-masses for GJ 724 b
and GJ 3988 b, respectively. Both planets have short periods (P<10d)
and, therefore, they orbit their star closely (a<0.05au). GJ 724 b has
an eccentric orbit (e=0.577+0.055-0.052), whereas the orbit of GJ
3988 b is circular. The high eccentricity of GJ 724 b makes it the
most eccentric single exoplanet (to this date) around an M dwarf.
Thus, we suggest a further analysis to understand its configuration in
the context of planetary formation and architecture. In contrast, GJ
3988 b is an example of a common type of planet around mid-M dwarfs.
Description:
The spectral data were obtained with CARMENES for both GJ 724 and
GJ 3988. We also incorporated RV data from the High Accuracy Radial
velocity Planet Searcher spectrograph (HARPS) for GJ 724. For GJ 3988,
we used data from the InfraRed Doppler (IRD) at the Subaru Telescope.
We discovered GJ 724 b and GJ 3988 b using RV measurements
from CARMENES, HARPS, and IRD. We measured the mean stellar rotation
periods for both stars using photometric data, obtaining 116±2d for
GJ 3988, and 57±1d for GJ 724, although we cannot completely exclude
its second harmonic (∼28d) as a possible rotation period.
Objects:
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RA (2000) DE Designation(s)
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18 40 57.30 -13 22 46.5 GJ 724 = TIC 424934357
17 03 23.88 +51 24 22.8 GJ 3988 = TIC 274626553
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
gj3988rv.dat 56 164 RV timeseries of GJ 3988
gj724rv.dat 56 110 RV timeseries of GJ 724
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Byte-by-byte Description of file: gj3988rv.dat gj724rv.dat
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Bytes Format Units Label Explanations
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1- 18 F18.10 d BJD Barycentric Julian Date
20- 33 F14.10 m/s RV Radial velocity
35- 47 F13.10 m/s e_RV Radial velocity error
49- 56 A8 --- Inst Instrument's name
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Acknowledgements:
Paula Gorrini, paula.gorrini(at)uni-goettingen.de
(End) Patricia Vannier [CDS] 23-Oct-2023