Grupo de Sistemas Estelares

Zechmeister, M.; Dreizler, S.; Ribas, I.; Reiners, A.; Caballero, J. A.; Bauer, F. F.; Béjar, V. J. S.; González-Cuesta, L.; Herrero, E.; Lalitha, S.; López-González, M. J.; Luque, R.; Morales, J. C.; Pallé, E.; Rodríguez, E.; Rodríguez López, C.; Tal-Or, L.; Anglada-Escudé, G.; Quirrenbach, A.; Amado, P. J. Abril, M.; Aceituno, F. J.; Aceituno, J.; Alonso-Floriano, F. J.; Ammler-von Eiff, M.; Antona Jiménez, R.; Anwand-Heerwart, H.; Arroyo-Torres, B.; Azzaro, M.; Baroch, D.; Barrado, D.; Becerril, S.; Benítez, D.; Berdiñas, Z. M.; Bergond, G.; Bluhm, P.; Brinkmöller, M.; del Burgo, C.; Calvo Ortega, R.; Cano, J.; Cardona Guillén, C.; Carro, J.; Cárdenas Vázquez, M. C.; Casal, E.; Casasayas-Barris, N.; Casanova, V.; Chaturvedi, P.; Cifuentes, C.; Claret, A.; Colomé, J.; Cortés-Contreras, M.; Czesla, S.; Díez-Alonso, E.; Dorda, R.; Fernández, M.; Fernández-Martín, A.; Fuhrmeister, B.; Fukui, A.; Galadí-Enríquez, D.; Gallardo Cava, I.; Garcia de la Fuente, J.; Garcia-Piquer, A.; García Vargas, M. L.; Gesa, L.; Góngora Rueda, J.; González-Álvarez, E.; González Hernández, J. I.; González-Peinado, R.; Grözinger, U.; Guàrdia, J.; Guijarro, A.; de Guindos, E.; Hatzes, A. P.; Hauschildt, P. H.; Hedrosa, R. P.; Helmling, J.; Henning, T.; Hermelo, I.; Hernández Arabi, R.; Hernández Castaño, L.; Hernández Otero, F.; Hintz, D.; Huke, P.; Huber, A.; Jeffers, S. V.; Johnson, E. N.; de Juan, E.; Kaminski, A.; Kemmer, J.; Kim, M.; Klahr, H.; Klein, R.; Klüter, J.; Klutsch, A.; Kossakowski, D.; Kürster, M.; Labarga, F.; Lafarga, M.; Llamas, M.; Lampón, M.; Lara, L. M.; Launhardt, R.; Lázaro, F. J.; Lodieu, N.; López del Fresno, M.; López-Puertas, M.; López Salas, J. F.; López-Santiago, J.; Magán Madinabeitia, H.; Mall, U.; Mancini, L.; Mandel, H.; Marfil, E.; Marín Molina, J. A.; Maroto Fernández, D.; Martín, E. L.; Martín-Fernández, P.; Martín-Ruiz, S.; Marvin, C. J.; Mirabet, E.; Montañés-Rodríguez, P.; Montes, D.; Moreno-Raya, M. E.; Nagel, E.; Naranjo, V.; Narita, N.; Nortmann, L.; Nowak, G.; Ofir, A.; Oshagh, M.; Panduro, J.; Parviainen, H.; Pascual, J.; Passegger, V. M.; Pavlov, A.; Pedraz, S.; Pérez-Calpena, A.; Pérez Medialdea, D.; Perger, M.; Perryman, M. A. C.; Rabaza, O.; Ramón Ballesta, A.; Rebolo, R.; Redondo, P.; Reffert, S.; Reinhardt, S.; Rhode, P.; Rix, H. -W.; Rodler, F.; Rodríguez Trinidad, A.; Rosich, A.; Sadegi, S.; Sánchez-Blanco, E.; Sánchez Carrasco, M. A.; Sánchez-López, A.; Sanz-Forcada, J.; Sarkis, P.; Sarmiento, L. F.; Schäfer, S.; Schmitt, J. H. M. M.; Schöfer, P.; Schweitzer, A.; Seifert, W.; Shulyak, D.; Solano, E.; Sota, A.; Stahl, O.; Stock, S.; Strachan, J. B. P.; Stuber, T.; Stürmer, J.; Suárez, J. C.; Tabernero, H. M.; Tala Pinto, M.; Trifonov, T.; Veredas, G.; Vico Linares, J. I.; Vilardell, F.; Wagner, K.; Wolthoff, V.; Xu, W.; Yan, F.; Zapatero Osorio, M. R.
Astronomy & Astrophysics, Volume 627, id.A49, 14 pp. (2019).
07/2019

ABSTRACT

Context. Teegarden's Star is the brightest and one of the nearest ultra-cool dwarfs in the solar neighbourhood. For its late spectral type (M7.0 V), the star shows relatively little activity and is a prime target for near-infrared radial velocity surveys such as CARMENES. 

Aims: As part of the CARMENES search for exoplanets around M dwarfs, we obtained more than 200 radial-velocity measurements of Teegarden's Star and analysed them for planetary signals. 
Methods: We find periodic variability in the radial velocities of Teegarden's Star. We also studied photometric measurements to rule out stellar brightness variations mimicking planetary signals. 
Results: We find evidence for two planet candidates, each with 1.1 M⊕ minimum mass, orbiting at periods of 4.91 and 11.4 d, respectively. No evidence for planetary transits could be found in archival and follow-up photometry. Small photometric variability is suggestive of slow rotation and old age. 
Conclusions: The two planets are among the lowest-mass planets discovered so far, and they are the first Earth-mass planets around an ultra-cool dwarf for which the masses have been determined using radial velocities. Tables D.1 and D.2 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/627/A49