A super-earth on a close-in orbit around the M1V star GJ 740: a HADES and CARMENES collaboration
<i>Context.<i/> M-dwarfs have proven to be ideal targets for planetary radial velocity (RV) searches due to their higher planet-star mass contrast, which favors the detection of low-mass planets. The abundance of super-Earth and Earth-like planets detected around this type of star motiva...
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| Hauptverfasser: | , , , , , , , , , , , , , , , , , , , , , , , , , |
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| Dokumenttyp: | Article (Journal) |
| Sprache: | Englisch |
| Veröffentlicht: |
10 February 2021
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| In: |
Astronomy and astrophysics
Year: 2021, Jahrgang: 648, Pages: 1-15 |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/202040099 |
| Online-Zugang: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1051/0004-6361/202040099 Verlag, lizenzpflichtig, Volltext: https://www.aanda.org/articles/aa/abs/2021/04/aa40099-20/aa40099-20.html 
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| Verfasserangaben: | B. Toledo-Padrón, A. Suárez Mascareño, J.I. González Hernández, R. Rebolo, M. Pinamonti, M. Perger, G. Scandariato, M. Damasso, A. Sozzetti, J. Maldonado, S. Desidera, I. Ribas, G. Micela, L. Affer, E. González-Alvarez, G. Leto, I. Pagano, R. Zanmar Sánchez, P. Giacobbe, E. Herrero, J.C. Morales, P.J. Amado, J.A. Caballero, A. Quirrenbach, A. Reiners, and M. Zechmeister |
| Zusammenfassung: | <i>Context.<i/> M-dwarfs have proven to be ideal targets for planetary radial velocity (RV) searches due to their higher planet-star mass contrast, which favors the detection of low-mass planets. The abundance of super-Earth and Earth-like planets detected around this type of star motivates further such research on hosts without reported planetary companions.<i>Aims.<i/> The HADES and CARMENES programs are aimed at carrying out extensive searches of exoplanetary systems around M-type stars in the northern hemisphere, allowing us to address, in a statistical sense, the properties of the planets orbiting these objects. In this work, we perform a spectroscopic and photometric study of one of the program stars (GJ 740), which exhibits a short-period RV signal that is compatible with a planetary companion.<i>Methods.<i/> We carried out a spectroscopic analysis based on 129 HARPS-N spectra taken over a time span of 6 yr combined with 57 HARPS spectra taken over 4 yr, as well as 32 CARMENES spectra taken during more than 1 yr, resulting in a dataset with a time coverage of 10 yr. We also relied on 459 measurements from the public ASAS survey with a time-coverage of 8 yr, along with 5 yr of photometric magnitudes from the EXORAP project taken in the <i>V<i/>, <i>B<i/>, <i>R<i/>, and <i>I<i/> filters to carry out a photometric study. Both analyses were made using Markov chain Monte Carlo simulations and Gaussian process regression to model the activity of the star.<i>Results.<i/> We present the discovery of a short-period super-Earth with an orbital period of 2.37756 d and a minimum mass of 2.96 <i>M<i/><sub>⊕<sub/>. We offer an update to the previously reported characterization of the magnetic cycle and rotation period of the star, obtaining values of <i>P<i/><sub>rot<sub/> = 35.563 ± 0.071 d and <i>P<i/><sub>cycle<sub/> = 2800 ± 150 d. Furthermore, the RV time series exhibits a possibly periodic long-term signal, which might be related to a Saturn-mass planet of ~100 <i>M<i/><sub>⊕<sub/>. |
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| Beschreibung: | Gesehen am 02.08.2021 |
| Beschreibung: | Online Resource |
| ISSN: | 1432-0746 |
| DOI: | 10.1051/0004-6361/202040099 |