J/A+A/620/A171 Radial velocities of GJ 3779 and GJ 1265 (Luque+, 2018)
The CARMENES search for exoplanets around M dwarfs. Two twin warm super-Earths
orbiting the mid-type M dwarfs Ross 1020 (GJ 3779) and LP 819-052 (GJ 1265).
Luque R., Nowak G., Palle E., Kossakowski D., Trifonov T., Zechmeister M.,
Bejar V.J.S., Cardona Guillen C., Tal-Or L., Hidalgo D., Ribas I.,
Reiners A., Caballero J.A., Amado P.J., Quirrenbach A., Aceituno J.,
Cortes-Contreras M., Diez-Alonso E., Dreizler S., Guenther E.W.,
Henning T., Jeffers S.V., Kaminski A., Kuerster M., Lafarga M., Montes D.,
Morales J.C., Passegger V.M., Schmitt J.H.M.M., Schweitzer A.
<Astron. Astrophys. 620, A171 (2018)>
=2018A&A...620A.171L 2018A&A...620A.171L (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Radial velocities
Keywords: techniques: radial velocities - stars: late-type - stars: low-mass -
planetary systems
Abstract:
We announce the discovery of two planetary companions orbiting around
the low-mass stars Ross 1020 (GJ 3779, M4.0V) and LP 819-052 (GJ 1265,
M4.5V). The discovery is based on the analysis of CARMENES radial
velocity (RV) observations in the visual channel as part of its survey
for exoplanets around M dwarfs. In the case of GJ 1265, CARMENES
observations were complemented with publicly available Doppler
measurements from HARPS. The datasets reveal two planetary companions,
one for each star, that share very similar properties: minimum masses
of 8.0±0.5M⊕ and 7.4±0.5M⊕ in low-eccentricity
orbits with periods of 3.023±0.001d and 3.651±0.001d for GJ 3779 b
and GJ 1265 b, respectively. The periodic signals around three days
found in the RV data have no counterpart in any spectral activity
indicator. Furthermore, we collected available photometric data for
the two host stars, which confirm that the additional Doppler
variations found at periods of approximately 95d can be attributed to
the rotation of the stars. The addition of these planets to a
mass-period diagram of known planets around M dwarfs suggests a
bimodal distribution with a lack of short-period low-mass planets in
the range of 2-5M⊕. It also indicates that super-Earths
(>5M⊕) currently detected by RV and transit techniques around
M stars are usually found in systems dominated by a single planet.
Description:
We analyzed radial velocity data from the CARMENES VIS channel for
GJ 3779, and from the CARMENES VIS channel and HARPS for GJ 1265. All
the RVs are corrected for barycentric motion and secular acceleration.
The CARMENES measurements were taken in the context of the CARMENES
search for exoplanets around M dwarfs. The CARMENES instrument
consists of two channels: the VIS channel obtains spectra at a
resolution of R=94600 in the wavelength range 520-960nm, while the NIR
channel yields spectra of R=80400 covering 960-1710nm. Both channels
are calibrated in wavelength with hollow-cathode lamps and use
temperature- and pressure-stabilized Fabry-Perot etalons to
interpolate the wavelength solution and simultaneously monitor the
spectrograph drift during nightly operations (Bauer et al.,
2015A&A...581A.117B 2015A&A...581A.117B).
Objects:
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RA (2000) DE Designation(s)
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13 22 56.74 +24 28 03.4 Ross 1020 = GJ 3779
22 13 42.78 -17 41 08.2 LP 819-052 = GJ 1265
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 34 104 GJ 3779 radial velocities
table2.dat 34 98 GJ 1265 radial velocities
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See also:
J/A+A/609/A117 : CARMENES radial velocity curves of 7 M-dwarf (Trifonov+ 2018)
J/A+A/609/L5 : HD 147379 b velocity curve (Reiners+, 2018)
J/A+A/618/A115 : HD 147379 radial velocities (Kaminski+, 2018)
Byte-by-byte Description of file: table1.dat table2.dat
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Bytes Format Units Label Explanations
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1- 12 F12.4 d BJD Barycentric Julian date of observation
14- 19 F6.2 m/s RV Radial velocity
21- 25 F5.2 m/s e_RV Radial velocity uncertainty
26- 34 A9 -- Inst Instrument (CARMENES or HARPS)
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Acknowledgements:
Rafael Luque, rluque(at)iac.es
(End) Rafael Luque [IAC, Spain], Patricia Vannier [CDS] 24-Oct-2018