Idiomas

The CARMENES search for exoplanets around M dwarfs. Two temperate Earth-mass planet candidates around Teegarden's Star

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.
arXiv:1906.07196
06/2019

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 (M7.0V), 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  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.