Examinando por Autor "Lodieu, N."

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Acceso Abierto
A giant exoplanet orbiting a very-low-mass star challenges planet formation models
(American Association for the Advancement of Science, 2019-09-27) Morales, J. C.; Mustill, A. J.; Ribas, I.; Davies, M. B.; Reiners, A.; Bauer, F. F.; Kossakowski, D.; Herrero, Enrique; Rodríguez, E.; López González, M. J.; Rodríguez López, C.; Stock, S.; Zechmeister, M.; Luque, R.; Gesa, L.; Pedraz, S.; Baroch, D.; Sarkis, P.; Lafarga, M.; Johnson, E. N.; Anglada Escudé, G.; González Álvarez, E.; Perryman, M. A. C.; Dreizler, S.; Sarmiento, L. F.; Tal Or, L.; Labarga, F.; Reffert, S.; Rebolo, R.; Schweitzer, A.; Schäfer, S.; Hagen, H. J.; Lázaro, F. J.; Quirrenbach, A.; Perger, M.; Guenther, E. W.; Schlecker, M.; Montes, D.; Jeffers, S. V.; Cortés Contreras, M.; Kürster, M.; Schmitt, J. H. M. M.; Aceituno, Francisco José; Abellán, F. J.; Rosich, A.; Aceituno, J.; Schöfer, P.; Arroyo Torres, B.; Amado, P. J.; Antona, R.; Solano, Enrique; Benítez, D.; Kaminski, A.; Becerril Jarque, S.; Sota, A.; Kehr, M.; Abril, M.; Brinkmöller, M.; Béjar, V. J. S.; Ammler von Eiff, M.; Calvo Ortega, R.; Zapatero Osorio, M. R.; Barrado, D.; Cardona Guillén, C.; Yan, F.; Bergond, G.; Casanova, V.; Klahr, H.; Chaturvedi, P.; Nagel, E.; Claret, A.; Trifonov, T.; Czesla, S.; Henning, T.; Dorda, R.; Seifert, W.; Fernández Hernández, Maite; Alonso Floriano, F. J.; Azzaro, M.; Berdiñas, Z. M.; Del Burgo, C.; Cano, J.; Carro, J.; Casasayas Barris, N.; Cifuentes, C.; Colomé, J.; Díez Alonso, E.; Emsenhuber, A.; Guàrdia, J.; Guijarro, A.; De Guindos, E.; Hatzes, Artie; Hauschildt, P. H.; Hedrosa, R. P.; Hermelo, I.; Hernández Arabi, R.; Hernández Otero, F.; Hintz, D.; Klüter, J.; González Peinado, R.; González Hernández, J. I.; González Cuesta, L.; De Juan, E.; Stahl, O.; Burn, R.; Kim, M.; Fernández Martín, A.; Lara, L. M.; Mordasini, C.; Labiche, N.; Cárdenas, M. C.; Lampón, M.; Ferro, I. M.; López del Fresno, M.; Passegger, V. M.; Lizon, Jean Louis; Casal, E.; Lodieu, N.; Fuhrmeister, B.; Mancini, L.; López Santiago, J.; Kemmer, J.; Mall, U.; Galadí Enríquez, D.; Martín Fernández, P.; Marfil, E.; Lalitha, S.; Martín, Eduardo L.; Gallardo Cava, I.; Mirabet, E.; Llamas, M.; Marvin, E. L.; García Vargas, M. L.; Nortmann, L.; Magán Madinabeitia, H.; Nelson, Richard; García Piquer, A.; Pallé, E.; Marín Molina, J. A.; Pascual Granado, J.; Caballero, J. A.; Martínez Rodríguez, H.; Pérez Medialdea, D.; Huke, P.; Naranjo, V.; Rabaza, O.; Huber, A.; Ofir, A.; Redondo, P.; Holgado, G.; Rodler, F.; Klutsch, A.; Sabotta, S.; Launhardt, R.; Salz, M.; López Salas, F. J.; Sánchez Carrasco, M. A.; Mandel, H.; Sanz Forcada, J.; Martín Ruiz, S.; Moya, A.; Nowak, G.; Pavlov, Alexander; Pérez Calpena, A.; Ramón Ballesta, A.; Rix, H. W.; Rodríguez Trinidad, A.; Sadegi, S.; Sánchez Blanco, E.; Sánchez López, A.; Stürmer, J.; Suárez, J. C.; Tabernero, H. M.; Tulloch, S. M.; Veredas, G.; Vico Linares, J. I.; Vilardell, F.; Wagner, K.; Winkler, J.; Wolthoff, V.; Johansen, A.; Stuber, T.; Israel Science Foundation (ISF); Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT); Swiss National Science Foundation (SNSF); Deutsches Zentrum für Luft- und Raumfahrt (DLR); Ministero dell'Istruzione, dell'Università e della Ricerca (MIUR); European Research Council (ERC); Generalitat de Catalunya; Deutsche Forschungsgemeinschaft (DFG); Queen Mary University of London; Consejo Nacional de Ciencia y Tecnología (CONACYT); Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737; Morales, J. C. [0000-0003-0061-518X]; Mustill, A. J. [0000-0002-2086-3642]; Ribas, I. [0000-0002-6689-0312]; Davies, M. B. [0000-0001-6080-1190]; Bauer, F. F. [0000-0003-1212-5225]; Herrrero, E. [0000-0001-8602-6639]; Rodríguez, E. [0000-0001-6827-9077]; López González, M. J. [0000-0001-8104-5128]; Rodríguez López, C. [0000-0001-5559-7850]; López González, M. J. [0000-0001-8104-5128]; Rodríguez López, C. [0000-0001-5559-7850]; Sarkis, P. [0000-0001-8128-3126]; López Santiago, J. [0000-0003-2402-8166]; Vilardell, F. [0000-0003-0441-1504]; Winkler, J. [0000-0003-0568-8820]; Nowak, G. [0000-0002-7031-7754]; Béjar, V. J. S. [0000-0002-5086-4232]; Luque, R. [0000-0002-4671-2957]; Pérez Calpena, A. [0000-0001-7361-9240]; Sota, A. [https://orcid.org/0000-0002-9404-6952]; Klahr, H. [0000-0002-8227-5467]; Mordasini, C. [0000-0002-1013-2811]; Rodler, F. [0000-0003-0650-5723]; Tabernero, H. [0000-0002-8087-4298]; Cortés Contreras, M. [0000-0003-3734-9866]; Lafarga, M. [0000-0002-8815-9416]; Sánchez López, A. [0000-0002-0516-7956]; Yan, F. [0000-0001-9585-9034]; Reffert, S. [0000-0002-0460-8289]; Rosich, A. [0000-0002-9141-3067]; Sarmiento, L. F. [0000-0002-8475-9705]; Perger, M. [0000-0001-7098-0372]; Sabotta, S. [0000-0001-9078-5574]; Guenther, E. W. [0000-0002-9130-6747]; Kaminski, A. [0000-0003-0203-8208]; Schmitt, J. H. M. M. [0000-0003-2554-9916]; Aceituno, J. [0000-0003-0487-1105]; Alonso Floriano, F. J. [0000-0003-1202-5734]; Stock, S. [0000-0002-1166-9338]; Nagel, E. [0000-0002-4019-3631]; Barrado, D. [0000-0002-5971-9242]; Tulloch, S. [0000-0003-0840-8521]; Trifonov, T. [0000-0002-0236-775X]; Bergond, G. [0000-0003-3132-9215]; Burn, R. [0000-0002-9020-7309]; Zapatero Osorio, M. R. [0000-0001-5664-2852]; Montes, D. [0000-0002-7779-238X]; Cano, J. [0000-0003-1984-5401]; Cardona Guillén, C. [0000-0002-2198-4200]; Baroch, D. [0000-0001-7568-5161]; Ammler-von Eiff, M. [0000-0001-9565-1698]; Chaturvedi, P. [0000-0002-1887-1192]; Cifuentes, C. [0000-0003-1715-5087]; Anglada Escudé, G. [0000-0002-3645-5977]; Becerril Jarque, S. [0000-0001-9009-1150]; González Cuesta, L. [0000-0002-1241-5508]; Díez Alonso, E. [0000-0002-5826-9892]; Emsenhuber, A. [0000-0002-8811-1914]; Passegger, V. M. [0000-0002-8569-7243]; García Vargas, M. L. [0000-0002-2058-3528]; González Álvarez, E. [0000-0002-4820-2053]; Amado, P. J. [0000-0002-8388-6040]; Carro, J. [0000-0002-0838-3603]; Guàrdia, J. [0000-0002-7191-9001]; Abellán, F. J. [0000-0002-5724-1636]; Colomé, J. [0000-0002-1678-2241]; Hermelo, I. [0000-0001-9178-694X]; Hintz, D. [0000-0002-5274-2589]; Arroyo Torres, B. [0000-0002-3392-4694]; Fuhrmeister, B. [0000-0001-8321-5514]; Johnson, E. [0000-0003-2260-5134]; De Juan Fernández, E. [0000-0002-9382-4505]; Berdiñas, Z. M. [0000-0002-6057-6461]; González Hernández, J. I. [0000-0002-0264-7356]; Klüter, J. [0000-0002-3469-5133]; Klutsch, A. [0000-0001-7869-3888]; Calvo Ortega, R. [0000-0003-3693-6030]; Guijarro, A. [0000-0001-5518-1759]; Aceituno, F. J. [0000-0001-8074-4760]; Lara, L. M. [0000-0002-7184-920X]; Launhardt, R. [0000-0002-8298-2663]; Casasayas Barris, N. [0000-0002-2891-8222]; López del Fresno, M. [0000-0002-9479-7780]; Magan Madinabeitia, H. [0000-0003-1243-4597]; Czesla, S. [0000-0002-4203-4773]; Kehr, M. [0000-0002-7420-7368]; Marín Molina, J. A. [0000-0002-3525-0806]; Galadí Enríquez, D. [0000-0003-4946-5653]; Labarga, F. [0000-0002-7143-0206]; Martínez Rodríguez, H. [0000-0002-1919-228X]; Marvin, C. J. [0000-0002-2249-2611]; González Peinado, R. [0000-0002-6658-8930]; Lizon, J. L. [0000-0001-8928-2566]; Naranjo, V. [0000-0003-0097-1061]; Nelson, R. [0000-0002-9687-8779]; De Guindos, E. [0000-0002-8124-9101]; Manici, L. [0000-0002-9428-8732]; Ofir, A. [0000-0002-9152-5042]; Pascual Granado, J. [0000-0003-0139-6951]; Huke, P. [0000-0001-5913-2743]; Martín, E. [0000-0002-1208-4833]; García Piquer, A. [0000-0002-6872-4262]; Rabaza, O. [0000-0003-2766-2103]; Ramón Ballesta, A. [0000-0002-4323-0610]; Kim, M. [0000-0001-6218-2004]; Rodríguez Trinidad, A. [0000-0002-3356-8634]; Sadegi, S. [0000-0001-9897-6121]; Lampón, M. [0000-0002-0183-7158]; Nortmann, L. [0000-0001-8419-8760]; Sanz Forcada, J. [0000-0002-1600-7835]; Lodieu, N. [0000-0002-3612-8968]; Pedraz, S. [0000-0003-1346-208X]; Schäfer, S. [0000-0001-8597-8048]; Schlecker, M. [0000-0001-8355-2107]; Marfil, E. [0000-0001-8907-4775]; Redondo, P. G. [0000-0001-5992-5778]; Schöfer, P. [0000-0002-5969-3708]; Solano, E. [0000-0003-1885-5130]; Martín Ruiz, S. [0000-0002-9006-7182]; Sánchez Carrasco, M. A. [0000-0001-5533-3660]; Stuber, T. [0000-0003-2185-0525]; Suárez, J. C. [0000-0003-3649-8384]; Moya, A. [0000-0003-1665-5389]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737; Centros de Excelencia Severo Ochoa, INSTITUTO DE ASTROFISICA DE ANDALUCIA (IAA), SEV-2017-0709
Surveys have shown that super-Earth and Neptune-mass exoplanets are more frequent than gas giants around low-mass stars, as predicted by the core accretion theory of planet formation. We report the discovery of a giant planet around the very-low-mass star GJ 3512, as determined by optical and near-infrared radial-velocity observations. The planet has a minimum mass of 0.46 Jupiter masses, very high for such a small host star, and an eccentric 204-day orbit. Dynamical models show that the high eccentricity is most likely due to planet-planet interactions. We use simulations to demonstrate that the GJ 3512 planetary system challenges generally accepted formation theories, and that it puts constraints on the planet accretion and migration rates. Disk instabilities may be more efficient in forming planets than previously thought.Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science
Acceso Abierto
Erratum: The first planet detected in the WTS: an inflated hot-Jupiter in a 3.35 day orbit around a late F-star
(Oxford Academics: Blackwell Publishing, 2020-07-28) Cappetta, M.; Saglia, R. P.; Birkby, J. L.; Koppenhoefer, J.; Pinfield, David J.; Hodgkin, S. T.; Cruz, P.; Kovács, G.; Sipocz, B.; Barrado, D.; Nefs, B.; Pavlenko, Y. V.; Fossati, L.; Del Burgo, C.; Martín, Eduardo L.; Snellen, J.; Barnes, J.; Campbell, D.; Catalan, S.; Gálvez Ortiz, M. C.; Goulding, N.; Haswell, C. A.; Ivanyuk, O.; Jones, H.; Kuznetsov, M.; Lodieu, N.; Marocco, F.; Mislis, D.; Murgas Alcaino, F.; Napiwotzki, R.; Pallé, E.; Pollacco, D.; Sarro Baro, L.; Solano, Enrique; Steele, P.; Stoev, H.; Tata, R.; Zendejas, J.; 0000-0003-0987-1593
Debido a su tipología(Corrección), carece de Abstract. Due to its typology, it has no Abstract. This is a correction to: Monthly Notices of the Royal Astronomical Society, Volume 427, Issue 3, December 2012, Pages 1877–1890, https://doi.org/10.1111/j.1365-2966.2012.21937.x
Acceso Abierto
Spectral library of age-benchmark low-mass stars and brown dwarfs
(Oxford Academics: Oxford University Press, 2020-12-27) Manjavacas, E.; Lodieu, N.; Béjar, V. J. S.; Zapatero Osorio, M. R.; Boudreault, S.; Bonnefoy, M.; Ministerio de Economía y Competitividad (MINECO); Agencia Estatal de Investigación (AEI); Manjavacas, E. [0000-0003-0192-6887]; Zapatero Osorio, M. R. [0000-0001-5664-2852]
In recent years, some extremely red brown dwarfs have been discovered. They were believed to have a low surface gravity, but many of their spectral characteristics are similar to those of high-surface-gravity brown dwarfs, showing that the spectral characteristics of young brown dwarfs are poorly understood. We aim to test surface-gravity indicators in late-M and early-L brown dwarf spectra using data obtained with the X-shooter spectrograph at the Very Large Telescope. We select a benchmark sample of brown dwarf members of Chamaeleon I (∼2 Myr), Upper Scorpius (5−10 Myr), the Pleiades (132 ± 27 Myr) and Praesepe (590−790 Myr) with well-constrained ages and similar metallicities. We provide a consistent spectral classification of the sample in the optical and in the near-infrared. We measure the equivalent widths of their alkali lines, finding that they have a moderate correlation with age, especially for objects with spectral types M8 and later. We use spectral indices defined in the literature to estimate surface gravity, finding that their gravity assignment is accurate for 75 per cent of our sample. We investigate the correlation between red colour and age, finding that after ∼10 Myr, the colour does not change significantly for our sample with spectral types M6.0–L3.0. In this case, the red colours might be associated with circumstellar discs, ring structures, extinction, or viewing angle. Finally, we calculate the bolometric luminosity, and J and K bolometric corrections for our sample. We find that six objects are overluminous compared with other members of the same association. These objects are flagged as binary candidates by the Gaia survey.
Acceso Abierto
Strong H alpha emission in the young planetary mass companion 2MASS J0249-0557 c
(EDP Sciences, 2021-01-15) Chinchilla, P.; Béjar, V. J. S.; Lodieu, N.; Zapatero Osorio, M. R.; Gauza, B.; European Southern Observatory (ESO); Agencia Estatal de Investigación (AEI); European Space Agency (ESA); Chinchilla, P. [0000-0002-3031-4911]; Lodieu, N. [0000-0002-3612-8968]; Gauza, B. [0000-0001-5452-2056]
Aims. Our objective is the optical and near-infrared spectroscopic characterisation of 2MASS J0249−0557 c, a recently discovered young planetary mass companion to the β Pictoris (~25 Myr) member 2MASS J0249−0557. Methods. Using the Visible and Infrared Survey Telescope for Astronomy Hemisphere Survey and the Two Micron All Sky Survey (2MASS) data, we independently identified the companion 2MASS J0249−0557 c. We also obtained low-resolution optical spectroscopy of this object using the Optical System for Imaging and low-intermediate-Resolution Integrated Spectroscopy spectrograph at the Gran Telescopio Canarias, and near-infrared spectroscopy using the Son of Isaac spectrograph on the New Technology Telescope. Results. We classified 2MASS J0249−0557 c with a spectral type of L2.5 ± 0.5 in the optical and L3 ± 1 in the near-infrared. We identified several spectroscopic indicators of youth both in the optical and in the near-infrared that are compatible with the age of the β Pictoris moving group: strong absorption due to oxides, weak alkaline atomic lines, and a triangular shape of the H-band pseudo-continuum. We also detect a strong Hα emission, with a pseudo-equivalent width (pEW) of −90−40+20 Å, which seems persistent at timescales from several days to a few years. This indicates strong chromospheric activity or disk accretion. Although many M-type brown dwarfs have strong Hα emission, this target is one of the very few L-type planetary mass objects in which this strong Hα emission has been detected. Lithium absorption at 6708 Å is observed with pEW ≲5 Å. We also computed the binding energy of 2MASS J0249−0557 c and obtained an (absolute) upper limit of U = (−8.8 ± 4.4) × 1032 J. Conclusions. Similarly to other young brown dwarfs and isolated planetary mass objects, strong Hα emission due to accretion or chromospheric activity is also present in young planetary mass companions at ages of some dozen million years. We also found that 2MASS J0249−0557 c is one of the wide substellar companions with the lowest binding energy known to date.
Acceso Abierto
The EChO science case
(Springer Link, 2015-11-29) Tinetti, G.; Drossart, P.; Eccleston, P.; Hartogh, P.; Isaak, K.; Linder, M.; Lovis, C.; Micela, G.; Olliver, M.; Puig, L.; Ribas, I.; Sicardy, B.; Kehoe, T.; Deeg, H.; Petrov, R.; Doel, P.; Tennyson, J.; Filacchione, G.; Varley, R.; Temple, J.; Lahav, O.; MacTavish, C.; Wisniowski, T.; Piccioni, G.; Guàrdia, J.; Cavarroc, C.; Jones, G.; Ade, P.; Sanromá, E.; Frith, J.; Lognonné, P.; Pantin, E.; Crook, J.; Colomé, J.; Allard, F.; Azzollini, R.; Burston, R.; Parviainen, H.; Malaguti, G.; Gerard, J. C.; Stamper, R.; Barrado, D.; Maldonado, J.; Morales, J. C.; Yurchenko, S. N.; Lagage, P. O.; Prinja, R.; Koskinen, T.; Waldmann, I.; Venot, O.; Heiter, U.; Lim, T.; Pace, E.; Moya Bedon, A.; Irwin, P.; Michaut, C.; Monteiro, M.; Jones, H.; Wawer, P.; Fouqué, P.; Widemann, T.; Alonso Floriano, F. J.; Eiroa, C.; Savini, G.; Stixrude, L.; Damasso, M.; Rataj, M.; Glasse, A.; Koskinen, T.; Bulgarelli, A.; Ciaravella, A.; Hollis, M.; Schmider, F. X.; Kerschbaum, F.; Licandro Goldaracena, J.; Claret, A.; Rocchetto, M.; López Valverde, Miguel Ángel; Fossey, S.; Leto, G.; Ramos Zapata, G.; Beaulieu, J. P.; Balado, A.; Luzzi, D.; Rebordao, J.; Encrenaz, T.; Adriani, A.; Alcala, J.; Guedel, M.; Morales Calderón, M.; Peña Ramírez, K. Y.; Herrero, Enrique; Focardi, M.; Montalto, M.; Wright, G.; Danielski, C.; Burleigh, M. R.; Medvedev, A.; Murgas Alcaino, F.; Chadney, J.; Bowles, N.; Maxted, Pierre; Kerschbaum, F.; Ward Thompson, D.; Laken, B.; Börne, P.; Christian Jessen, N.; Dominic, C.; López Morales, M.; Miles Paez, P.; Achilleos, N.; Biondi, D.; White, G.; Heredero, R. L.; De Kok, R.; Frith, J.; Grodent, D.; Rank Lüftinger, T.; Scholz, A.; Villaver, E.; Dobrijévic, M.; Alard, C.; Demangeon, O. D. S.; De Witt, J.; Machado, P.; Cordier, D.; Charnoz, S.; Rodler, F.; Gerard, J. C.; Sousa, S. G.; Viti, S.; Cole, R.; Blecka, M.; Barber, R. J.; Middleton, K.; Griffin, M.; Giro, E.; Cho, J.; Covino, E.; Turrini, D.; Moro Martín, A.; Decin, L.; Ramos, A. A.; Schrader, J. R.; Massi, F.; Abe, L.; Mauskopf, P.; Batista, V.; Agnor, C.; Bordé, P.; Fabrizio, N.; Bakos, G.; Rengel, M.; Gustin, J.; Hueso, R.; Fernández Hernández, Maite; Ray, T.; Claudi, R.; Femenía Castella, B.; Rebolo, R.; Sethenadh, J.; Luntzer, A.; Mueller Wodarg, I.; Delgado Mena, E.; Brown, L.; De Sio, A.; González Hernández, J.; Selsis, F.; Leconte, J.; Del Vecchio, C.; Budaj, J.; Scandariato, G.; Pagano, I.; García Piquer, A.; Guillot, T.; Terenzi, L.; Tabernero, H. M.; Forget, F.; Hargrave, P.; North, C.; Heyrovsky, D.; Cerulli, R.; Adybekian, V.; Read, P.; Pinsard, Frederic; Parmentier, V.; Collura, A.; Hubert, B.; Lanza, N.; Graczyk, R.; Fouqué, P.; Giuranna, M.; Valdivieso, M. L.; Pérez Hoyos, S.; Andersen, A.; Mall, U.; Buchhave, L. A.; Yelle, R.; Rickman, H.; Ballerini, P.; Affer, L.; Maruquette, J. B.; Sánchez Béjar, V. J.; Nelson, Richard; Fletcher, L.; Radioti, A.; Turrini, D.; Montes, D.; Gizon, L.; Galand, M.; Gómez, H.; Eymet, V.; Esposito, M.; Smith, A.; Morello, G.; Allende Prieto, C.; Justtanot, K.; Bryson, I.; Pallé, E.; Amado, P. J.; Figueira, P.; Shore, Steven; Focardi, M.; Strazzulla, G.; Giani, E.; Pietrzak, R.; González Merino, B.; Lo Cicero, Ugo; Gaulme, P.; Sozzetti, A.; Femenía Castella, B.; Maillard, J. P.; Cabral, A.; Iro, N.; Magnes, W.; Pinfield, David J.; Swain, M.; Showman, A.; Bellucci, G.; Kerins, E.; Maurin, A. S.; Poretti, E.; Boisse, I.; Barton, E. J.; Kervella, P.; Guio, P.; Norgaard Nielsen, H. U.; Bézard, B.; Montañés Rodríguez, P.; Banaszkiewicz, M.; Kovács, G.; Baffa, C.; Del Val Borro, M.; Belmonte Avilés, J. A.; Palla, F.; Hersant, F.; Correira, A.; Yung, Y.; Cockell, Charles S.; Vinatier, S.; Pilat Lohinger, E.; Krupp, N.; Orton, G.; Vakili, F.; Pezzuto, S.; Di Giorgio, A.; Waltham, D.; Testi, L.; Stiepen, A.; Deroo, P.; Capria, M. T.; Eales, S.; Irshad, R.; Stolarski, M.; Zapatero Osorio, M. R.; Swinyard, B.; Griffith, C.; Winek, W.; Bouy, H.; Thompson, S.; Maggio, A.; Moses, J.; Liu, S. J.; Lithgow Bertelloni, C.; Coudé du Foresto, V.; Martín Torres, Javier; Fletcher, L.; Barlow, M.; Coustenis, A.; Berry, D.; López Puertas, M.; Banaszkiewicz, M.; Lundgaard Rasmussen, I.; Hoogeveen, Ruud; Morais, H.; Watkins, C.; Oliva, E.; Scuderi, S.; Aylward, A.; Bonford, B.; Sitek, P.; Haigh, J.; Prisinzano, L.; Soret, L.; Wawrzaszk, A.; Lammer, H.; Figueira, P.; Gianotti, F.; Readorn, K.; Tanga, P.; Israelian, G.; Gesa, L.; Peralta, J.; Gómez Leal, I.; Cassan, A.; Tecsa, M.; Tessenyi, M.; Pancrazzi, M.; Coates, A.; Gambicorti, L.; Gear, W.; Winter, B.; Piskunov, N.; Álvarez Iglesias, C. A.; Polichtchouk, I.; Altieri, F.; Ottensamer, R.; Watson, D.; Rezac, L.; Vandenbussche, B.; Waters, R.; Dorfi, E.; Morgante, G.; Pascale, E.; Hornstrup, A.; Snellen, Ignas; Lodieu, N.; Lellouch, E.; Espinoza Contreras, M.; Jarchow, C.; Agúndez, Marcelino; Filacchione, G.; Abreu, M.; Grassi, D.; Tingley, B. W.; Sánchez Lavega, Agustín; Tozzi, A.; Sanz Forcada, J.; Kipping, D.; Chamberlain, S.; Trifoglio, M.; Barstow, J. K.; Santos, Nuno C.; Gillon, M.; Hébrard, E.; Cecchi Pestellini, C.; Fossey, S.; García López, Ramón; Thrastarson, H.; Rees, J. M.; Selig, A.; Galand, M.; Jacquemoud, S.; Branduardi Raymont, Graziella; Rebordao, J. [0000-0002-7418-0345]; Kerschbaum, F. [0000-0001-6320-0980]; Abreu, M. [0000-0002-0716-9568]; Tabernero, H. [0000-0002-8087-4298]; López Puertas, M. [0000-0003-2941-7734]; Jacquemoud, S. [0000-0002-1500-5256]; Tennyson, J. [0000-0002-4994-5238]; Focardi, M. [0000-0002-3806-4283]; Leto, G. [0000-0002-0040-5011]; Lodieu, N. [0000-0002-3612-8968]; Tinetti, G. [0000-0001-6058-6654]; Danielski, C. [0000-0002-3729-2663]; Hornstrup, A. [0000-0002-3363-0936]; Kervella, P. [0000-0003-0626-1749]; Sánchez Bejar, V. [0000-0002-5086-4232]; López Heredero, R. [0000-0002-2197-8388]; Sanz Forcada, J. [0000-0002-1600-7835]; Rickman, H. [0000-0002-9603-6619]; Maggio, A. [0000-0001-5154-6108]; Medved, A. [0000-0003-2713-8977]; Tinetti, G. [0000-0001-6058-6654]; Fletcher, L. [0000-0001-5834-9588]; Haigh, J. [0000-0001-5504-4754]; Bakos, G. [0000-0001-7204-6727]; Stixrude, L. [0000-0003-3778-2432]; Amado, P. J. [0000-0002-8388-6040]; Martín Torres, J. [0000-0001-6479-2236]; Correira, A. [0000-0002-8946-8579]; Yurchenko, S. [0000-0001-9286-9501]; Rataj, M. [0000-0002-2978-9629]; Guedel, M. [0000-0001-9818-0588]; Piskunov, N. [0000-0001-5742-7767]; Filacchione, G. [0000-0001-9567-0055]; Adibekyan, V. [0000-0002-0601-6199]; Budaj, J. [0000-0002-9125-7340]; Poretti, E. [0000-0003-1200-0473]; Pascale, E. [0000-0002-3242-8154]; Claudi, R. [0000-0001-7707-5105]; Piccioni, G. [0000-0002-7893-6808]; Ribas, I. [0000-0002-6689-0312]; Sanroma, E. [0000-0001-8859-7937]; Agundez, M. [0000-0003-3248-3564]; Montes, D. [0000-0002-7779-238X]; Lognonne, P. [0000-0002-1014-920X]; Abreu, M. [0000-0002-0716-9568]; Montes, D. [0000-0002-7779-238X]; Morais, M. H. [0000-0001-5333-2736]; Tanga, P. [0000-0002-2718-997X]; Peralta, J. [0000-0002-6823-1695]; Hueso, R. [0000-0003-0169-123X]; Leto, G. [0000-0002-0040-5011]; Morales, J. C. [0000-0003-0061-518X]; Pérez Hoyos, S. [0000-0002-2587-4682]; Santos, N. [0000-0003-4422-2919]; Lithgow Bertelloni, C. [0000-0003-0924-6587]; Delgado, M. E. [0000-0003-4434-2195]; Barlow, M. [0000-0002-3875-1171]; Deeg, H. [0000-0003-0047-4241]; Bouy, H. [0000-0002-7084-487X[; Grassi, D. [0000-0003-1653-3066]; Figueira, P. [0000-0001-8504-283X]; Barton, E. [0000-0001-5945-9244]; Coates, A. [0000-0002-6185-3125]; García Ramón, J. [0000-0002-8204-6832]; Watson, D. [0000-0002-4465-8264]; Morales Calderon, M. [0000-0001-9526-9499]; Demangeon, O. [0000-0001-7918-0355]; Ray, T. [0000-0002-2110-1068]; Guio, P. [0000-0002-1607-5862]; Gillon, M. [0000-0003-1462-7739]; Bulgarelli, A. [0000-0001-6347-0649]; Prisinzano, L. [0000-0002-8893-2210]; Barstow, J. [0000-0003-3726-5419]; Pancrazzi, M. [0000-0002-3789-2482]; Barrado Navascues, D. [0000-0002-5971-9242]; Balado, A. [0000-0003-4268-2516]; Malaguti, G. [0000-0001-9872-3378]; Zapatero Osorio, M. R. [0000-0001-5664-2852]; Affer, L. [0000-0001-5600-3778]; Ciaravella, A. [0000-0002-3127-8078]; Guillot, T. [0000-0002-7188-8428]; Altieri, F. [0000-0002-6338-8300]; Covino, E. [0000-0002-6187-6685]; Venot, O. [0000-0003-2854-765X]; López Valverde, M. A. [0000-0002-7989-4267]; Cabral, A. [0000-0002-9433-871X]; Selsis, F. [0000-0001-9619-5356]; Turrini, D. [0000-0002-1923-7740]; Ward Thompson, D. [0000-0003-1140-2761]; Rebolo, R. [0000-0003-3767-7085]; Damasso, M. [0000-0001-9984-4278]; Tizzi, A. [0000-0002-6725-3825]; Morgante, G. [0000-0001-9234-7412]; Pena Ramírez, K. [0000-0002-5855-401X]; Galand, M. [0000-0001-5797-914X]; Pace, E. [0000-0001-5870-1772]; Pilat Lohinger, E. [0000-0002-5292-1923]; Sánchez Lavega, A. [0000-0001-7234-7634]; Waldmann, I. [0000-0002-4205-5267]; Claret, A. [0000-0002-4045-8134]; Olivia, E. [0000-0002-9123-0412]; Kovacs, G. [0000-0002-2365-2330]; Gómez, H. [0000-0003-3398-0052]; Monteiro, M. [0000-0001-5644-0898]; Bellucci, G. [0000-0003-0867-8679]; Baffa, C. [0000-0002-4935-100X]; Scholz, A. [0000-0001-8993-5053]; Bezard, B. [0000-0002-5433-5661]; Scuderi, Salvatore [0000-0002-8637-2109]; Hersant, F. [0000-0002-2687-7500]; Maldonado, J. [0000-0002-4282-1072]; Gear, W. [0000-0001-6789-6196]; Sousa, S. [0000-0001-9047-2965]; Irwin, P. [0000-0002-6772-384X]; Pinfield, D. [0000-0002-7804-4260]; Kipping, D. [0000-0002-4365-7366]; Ade, P. [0000-0002-5127-0401]; Vandenbussche, B. [0000-0002-1368-3109]; Burleigh, M. [0000-0003-0684-7803]; Chadney, J. [0000-0002-5174-2114]; Moro Martín, A. [0000-0001-9504-8426]; Scandariato, G. [0000-0003-2029-0626]; Rodríguez, P. [0000-0002-6855-9682]; Maldonado, J. [0000-0002-2218-5689]; Michaut, C. [0000-0002-2578-0117]; Pérez Hoyos, S. [0000-0001-9797-4917]
The discovery of almost two thousand exoplanets has revealed an unexpectedly diverse planet population. We see gas giants in few-day orbits, whole multi-planet systems within the orbit of Mercury, and new populations of planets with masses between that of the Earth and Neptune—all unknown in the Solar System. Observations to date have shown that our Solar System is certainly not representative of the general population of planets in our Milky Way. The key science questions that urgently need addressing are therefore: What are exoplanets made of? Why are planets as they are? How do planetary systems work and what causes the exceptional diversity observed as compared to the Solar System? The EChO (Exoplanet Characterisation Observatory) space mission was conceived to take up the challenge to explain this diversity in terms of formation, evolution, internal structure and planet and atmospheric composition. This requires in-depth spectroscopic knowledge of the atmospheres of a large and well-defined planet sample for which precise physical, chemical and dynamical information can be obtained. In order to fulfil this ambitious scientific program, EChO was designed as a dedicated survey mission for transit and eclipse spectroscopy capable of observing a large, diverse and well-defined planet sample within its 4-year mission lifetime. The transit and eclipse spectroscopy method, whereby the signal from the star and planet are differentiated using knowledge of the planetary ephemerides, allows us to measure atmospheric signals from the planet at levels of at least 10−4 relative to the star. This can only be achieved in conjunction with a carefully designed stable payload and satellite platform. It is also necessary to provide broad instantaneous wavelength coverage to detect as many molecular species as possible, to probe the thermal structure of the planetary atmospheres and to correct for the contaminating effects of the stellar photosphere. This requires wavelength coverage of at least 0.55 to 11 μm with a goal of covering from 0.4 to 16 μm. Only modest spectral resolving power is needed, with R ~ 300 for wavelengths less than 5 μm and R ~ 30 for wavelengths greater than this. The transit spectroscopy technique means that no spatial resolution is required. A telescope collecting area of about 1 m2 is sufficiently large to achieve the necessary spectro-photometric precision: for the Phase A study a 1.13 m2 telescope, diffraction limited at 3 μm has been adopted. Placing the satellite at L2 provides a cold and stable thermal environment as well as a large field of regard to allow efficient time-critical observation of targets randomly distributed over the sky. EChO has been conceived to achieve a single goal: exoplanet spectroscopy. The spectral coverage and signal-to-noise to be achieved by EChO, thanks to its high stability and dedicated design, would be a game changer by allowing atmospheric composition to be measured with unparalleled exactness: at least a factor 10 more precise and a factor 10 to 1000 more accurate than current observations. This would enable the detection of molecular abundances three orders of magnitude lower than currently possible and a fourfold increase from the handful of molecules detected to date. Combining these data with estimates of planetary bulk compositions from accurate measurements of their radii and masses would allow degeneracies associated with planetary interior modelling to be broken, giving unique insight into the interior structure and elemental abundances of these alien worlds. EChO would allow scientists to study exoplanets both as a population and as individuals. The mission can target super-Earths, Neptune-like, and Jupiter-like planets, in the very hot to temperate zones (planet temperatures of 300–3000 K) of F to M-type host stars. The EChO core science would be delivered by a three-tier survey. The EChO Chemical Census: This is a broad survey of a few-hundred exoplanets, which allows us to explore the spectroscopic and chemical diversity of the exoplanet population as a whole. The EChO Origin: This is a deep survey of a subsample of tens of exoplanets for which significantly higher signal to noise and spectral resolution spectra can be obtained to explain the origin of the exoplanet diversity (such as formation mechanisms, chemical processes, atmospheric escape). The EChO Rosetta Stones: This is an ultra-high accuracy survey targeting a subsample of select exoplanets. These will be the bright “benchmark” cases for which a large number of measurements would be taken to explore temporal variations, and to obtain two and three dimensional spatial information on the atmospheric conditions through eclipse-mapping techniques. If EChO were launched today, the exoplanets currently observed are sufficient to provide a large and diverse sample. The Chemical Census survey would consist of > 160 exoplanets with a range of planetary sizes, temperatures, orbital parameters and stellar host properties. Additionally, over the next 10 years, several new ground- and space-based transit photometric surveys and missions will come on-line (e.g. NGTS, CHEOPS, TESS, PLATO), which will specifically focus on finding bright, nearby systems. The current rapid rate of discovery would allow the target list to be further optimised in the years prior to EChO’s launch and enable the atmospheric characterisation of hundreds of planets.
Restringido
Two close binaries across the hydrogen-burning limit in the Praesepe open cluster
(Oxford Academics: Oxford University Press, 2020-08-21) Lodieu, N.; Del Burgo, C.; Manjavacas, E.; Zapatero Osorio, M. R.; Álvarez, C.; Béjar, V. J. S.; Boudreault, S.; Lyke, J.; Rebolo, R.; Chinchilla, P.; Consejo Nacional de Ciencia y Tecnología (CONACYT); Ministerio de Economía y Competitividad (MINECO); Manjavacas, E. [0000-0003-0192-6887]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
We present Keck I/OSIRIS and Keck II/NIRC2 adaptive optics imaging of two member candidates of the Praesepe stellar cluster (d = 186.18 ± 0.11 pc; 590–790 Myr), UGCS J08451066+2148171 (L1.5 ± 0.5) and UGCS J08301935+2003293 (no spectroscopic classification). We resolved UGCS J08451066+2148171 into a binary system in the near-infrared, with a K-band wavelength flux ratio of 0.89 ± 0.04 and a projected separation of 60.3 ± 1.3 mas (11.2 ± 0.7 au; 1σ). We also resolved UGCS J08301935+2003293 into a binary system with a flux ratio of 0.46 ± 0.03 and a separation of 62.5 ± 0.9 mas. Assuming zero eccentricity, we estimate minimum orbital periods of ∼100 yr for both systems. According to theoretical evolutionary models, we derive masses in the range of 0.074–0.078 and 0.072–0.076 M⊙ for the primary and secondary of UGCS J08451066+2148171 for an age of 700 ± 100 Myr. In the case of UGCS J08301935+2003293, the primary is a low-mass star at the stellar/substellar boundary (0.070–0.078 M⊙), while the companion candidate might be a brown dwarf (0.051–0.065 M⊙). These are the first two binaries composed of L dwarfs in Praesepe. They are benchmark systems to derive the location of the substellar limit at the age and metallicity of Praesepe, determine the age of the cluster based on the lithium depletion boundary test, derive dynamical masses, and improve low-mass stellar and substellar evolutionary models at a well-known age and metallicity.
Restringido
Ultracool dwarfs in deep extragalactic surveys using the virtual observatory: ALHAMBRA and COSMOS
(Oxford Academics: Oxford University Press, 2021-02-01) Solano, Enrique; Gálvez Ortiz, M. C.; Martín, Eduardo L.; Gómez Muñoz, I. M.; Rodrigo, C.; Burgasser, A. J.; Lodieu, N.; Béjar, V. J. S.; Huélamo, N.; Morales Calderón, M.; Bouy, H.; Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO); Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Ultracool dwarfs (UCDs) encompass a wide variety of compact stellar-like objects with spectra classified as late-M, L, T, and Y. Most of them have been discovered using wide-field imaging surveys. The Virtual Observatory (VO) has proven to be of great utility to efficiently exploit these astronomical resources. We aim to validate a VO methodology designed to discover and characterize UCDs in deep extragalactic surveys like Advance Large Homogeneous Area Medium-Band Redshift Astronomical (ALHAMBRA) and Cosmological Evolution Survey (COSMOS). Three complimentary searches based on parallaxes, proper motions and colours, respectively, were carried out. A total of 897 candidate UCDs were found, with only 16 previously reported in SIMBAD. Most of the new UCDs reported here are likely late-M and L dwarfs because of the limitations imposed by the utilization of optical (Gaia DR2 and r-band) data. We complement ALHAMBRA and COSMOS photometry with other catalogues in the optical and infrared using VOSA, a VO tool that estimates effective temperatures from the spectral energy distribution fitting to collections of theoretical models. The agreement between the number of UCDs found in the COSMOS field and theoretical estimations together with the low false-negative rate (known UCDs not discovered in our search) validates the methodology proposed in this work, which will be used in the forthcoming wide and deep surveys provided by the Euclid space mission. Simulations of Euclid number counts for UCDs detectable in different photometric passbands are presented for a wide survey area of 15 000 deg2, and the limitations of applicability of Euclid data to detect UCDs using the methods employed in this paper are discussed.
Acceso Abierto
USco1621 B and USco1556 B: Two wide companions at the deuterium-burning mass limit in Upper Scorpius
(EDP Sciences, 2020-01-24) Chinchilla, P.; Béjar, V. J. S.; Lodieu, N.; Gauza, B.; Zapatero Osorio, M. R.; Rebolo, R.; Pérez Garrido, A.; Álvarez, C.; Manjavacas, E.; European Southern Observatory (ESO); Agencia Estatal de Investigación (AEI); Ministerio de Economía y Competitividad (MINECO); Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT); Chinchilla, P. [0000-0002-3031-4911]; Béjar, V. J. S. [0000-0002-5086-4232]; Lodieu, N. [0000-0002-3612-8968]; Gauza, B. [0000-0001-5452-2056]; Zapatero Osorio, M. R. [0000-0001-5664-2852]; Rebolo, R. [0000-0003-3767-7085]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Aims. Our objective is to identify analogues of gas giant planets, but located as companions at wide separations of very young stars. The main purpose is to characterise the binarity frequency and the properties of these substellar objects, and to elucidate their early evolutionary stages. Methods. To identify these objects, we cross correlated the Visible and Infrared Survey Telescope for Astronomy Hemisphere Survey and the United Kingdom Infrared Telescope Infrared Deep Sky Survey Galactic Clusters Survey catalogues to search for common proper motion companions to 1195 already known members of Upper Scorpius (USco; age ~5–10 Myr, distance ~145 pc). We present the discovery and spectroscopic characterisation of two very wide substellar companions of two early-M stars in Upper Scorpius: USco1621 B and USco1556 B. We obtained optical and near-infrared low-resolution spectroscopy of the candidates to characterise their spectral energy distribution and confirm their youth and membership to the association. We also acquired adaptive optics images of the primaries and secondaries to search for signs of binarity and close companions. Results. By comparison with field dwarfs and other young members of USco, we determined a spectral type of M8.5 in the optical for both companions, along with L0 and L0.5 in the near-infrared for USco1621 B and USco1556 B, respectively. The spectra of the two companions show evident markers of youth, such as weak alkaline Na I and K I lines, along with the triangular shape of the H-band. The comparison with theoretical evolutionary models gives estimated masses of 0.015 ± 0.002 and 0.014 ± 0.002 M⊙, with temperatures of 2270 ± 90 and 2240 ± 100 K, respectively. The physical separations between the components of both systems are 2880 ± 20 and 3500 ± 40 AU for USco1621 and USco1556 systems, respectively. We did not find any additional close companion in the adaptive optics images. The probability that the two secondaries are physically bound to their respective primaries, and not chance alignments of USco members, is 86%, and the probability that none of them are physically related is 1.0%.
Acceso Abierto
Wide companions to M and L subdwarfs with Gaia and the Virtual Observatory
(EDP Sciences, 2021-06-29) González Payo, J.; Cortés Contreras, M.; Lodieu, N.; Solano, Enrique; Zhang, Z. H.; Gálvez Ortiz, M. C.; Agencia Estatal de Investigación (AEI); European Research Council (ERC)
Aims. The aim of the project is to identify wide common proper motion companions to a sample of spectroscopically confirmed M and L metal-poor dwarfs (also known as subdwarfs) to investigate the impact of metallicity on the binary fraction of low-mass metal-poor binaries and to improve the determination of their metallicity from the higher-mass binary. Methods. We made use of Virtual Observatory tools and large-scale public surveys to look in Gaia for common proper motion companions to a well-defined sample of ultracool subdwarfs with spectral types later than M5 and metallicities below or equal to −0.5 dex. We collected low-resolution optical spectroscopy for our best system, which is a binary composed of one sdM1.5 subdwarf and one sdM5.5 subdwarf located at ∼1360 au, and for another two likely systems separated by more than 115 000 au. Results. We confirm one wide companion to an M subdwarf, and infer a multiplicity for M subdwarfs (sdMs) of 1.0−1.0+2.0% for projected physical separations of up to 743 000 au. We also find four M–L systems, three of which are new detections. No colder companion was identified in any of the 219 M and L subdwarfs of the sample, mainly because of limitations on the detection of faint sources with Gaia. We infer a frequency of wide systems for sdM5–9.5 of 0.60−0.60+1.17% for projected physical separations larger than 1 360 au (up to 142 400 au). This study shows a multiplicity rate of 1.0−1.0+2.0% in sdMs, and 1.9−1.9+3.7% in extreme M subdwarfs. We did not find any companion for the ultra M subdwarfs of our sample, establishing an upper limit of 5.3% on binarity for these objects.