Examinando por Autor "Maldonado, J."

Mostrando 1 - 6 de 6

Acceso Abierto
Gliese 49: activity evolution and detection of a super-Earth A HADES and CARMENES collaboration
(EDP Sciences, 2019-04-24) Perger, M.; Scandariato, G.; Ribas, I.; Morales, J. C.; Affer, L.; Azzaro, M.; Amado, P. J.; Anglada Escudé, G.; Baroch, D.; Barrado, D.; Bauer, F. F.; Béjar, V. J. S.; Caballero, J. A.; Cortés Contreras, M.; Damasso, M.; Dreizler, S.; González Cuesta, L.; Guenther, E. W.; Henning, T.; Herrero, E.; Jeffers, S. V.; Kaminski, A.; Kürster, M.; Lafarga, M.; Leto, G.; López González, M. J.; Maldonado, J.; Micela, G.; Montes, D.; Pinamonti, M.; Quirrenbach, A.; Rebolo, R.; Reiners, A.; Rodríguez, E.; Rodríguez López, C.; Schimitt, J. H. M. M.; Sozzetti, A.; Suárez Mascareño, A.; Toledo Padrón, B.; Zanmar Sánchez, R.; Zapatero Osorio, M. R.; Zechmeister, M.; González Hernández, Carmen; Ministerio de Economía y Competitividad (MINECO); European Commission (EC); Agencia Estatal de Investigación (AEI); 0000-0001-7098-0372; Centros de Excelencia Severo Ochoa, INSTITUTO DE ASTROFISICA DE ANDALUCIA (IAA), SEV-2017-0709; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. Small planets around low-mass stars often show orbital periods in a range that corresponds to the temperate zones of their host stars which are therefore of prime interest for planet searches. Surface phenomena such as spots and faculae create periodic signals in radial velocities and in observational activity tracers in the same range, so they can mimic or hide true planetary signals. Aims. We aim to detect Doppler signals corresponding to planetary companions, determine their most probable orbital configurations, and understand the stellar activity and its impact on different datasets. Methods. We analyzed 22 yr of data of the M1.5 V-type star Gl 49 (BD+61 195) including HARPS-N and CARMENES spectrographs, complemented by APT2 and SNO photometry. Activity indices are calculated from the observed spectra, and all datasets are analyzed with periodograms and noise models. We investigated how the variation of stellar activity imprints on our datasets. We further tested the origin of the signals and investigate phase shifts between the different sets. To search for the best-fit model we maximize the likelihood function in a Markov chain Monte Carlo approach. Results. As a result of this study, we are able to detect the super-Earth Gl 49b with a minimum mass of 5.6 M⊕. It orbits its host star with a period of 13.85 d at a semi-major axis of 0.090 au and we calculate an equilibrium temperature of 350 K and a transit probability of 2.0%. The contribution from the spot-dominated host star to the different datasets is complex, and includes signals from the stellar rotation at 18.86 d, evolutionary timescales of activity phenomena at 40–80 d, and a long-term variation of at least four years.
Acceso Abierto
HADES RV Programme with HARPS-N at TNG XIII. A sub-Neptune around the M dwarf GJ 720 A
(EDP Sciences, 2021-05-31) González Álvarez, E.; Petralia, A.; Micela, G.; Maldonado, J.; Affer, L.; Maggio, A.; Covino, E.; Damasso, M.; Lanza, A. F.; Perger, M.; Pinamonti, M.; Poretti, E.; Scandariato, G.; Sozzetti, A.; Bignamini, A.; Giacobbe, P.; Leto, G.; Pagano, I.; Zanmar Sánchez, R.; Rebolo, R.; Ribas, I.; Suárez Mascareño, A.; Toledo Padrón, B.; González Hernández, Carmen; National Science Foundation (USA NSF); Agenzia Spaziale Italiana (ASI); Generalitat de Catalunya; Fundación Caixa; Agencia Estatal de Investigación (AEI); González Álvarez, E. [0000-0002-4820-2053]; Petralia, A. [0000-0002-9882-1020]; Maldonado, J. [0000-0002-2218-5689]; Affer, L. [0000-0001-5600-3778]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. The high number of super-Earth and Earth-like planets in the habitable zone detected around M-dwarf stars in recent years has revealed these stellar objects to be the key to planetary radial velocity (RV) searches. Aims. Using the HARPS-N spectrograph within The HArps-n red Dwarf Exoplanet Survey (HADES) we have reached the precision needed to detect small planets with a few Earth masses using the spectroscopic radial velocity technique. HADES is mainly focused on the M-dwarf population of the northern hemisphere. Methods. We obtained 138 HARPS-N RV measurements between 2013 May and 2020 September of GJ 720 A, classified as an M0.5 V star located at a distance of 15.56 pc. To characterize the stellar variability and to distinguish the periodic variation due to the Keplerian signals from those related to stellar activity, the HARPS-N spectroscopic activity indicators and the simultaneous photometric observations with the APACHE and EXORAP transit surveys were analyzed. We also took advantage of TESS, MEarth, and SuperWASP photometric surveys. The combined analysis of HARPS-N RVs and activity indicators let us address the nature of the periodic signals. The final model and the orbital planetary parameters were obtained by simultaneously fitting the stellar variability and the Keplerian signal using a Gaussian process regression and following a Bayesian criterion. Results. The HARPS-N RV periodic signals around 40 days and 100 days have counterparts at the same frequencies in HARPS-N activity indicators and photometric light curves. We thus attribute these periodicities to stellar activity; the first period is likely associated with the stellar rotation. GJ 720 A shows the most significant signal at 19.466 ± 0.005 days with no counterparts in any stellar activity indices. We hence ascribe this RV signal, having a semi-amplitude of 4.72 ± 0.27 m s−1, to the presence of a sub-Neptune mass planet. The planet GJ 720 Ab has a minimum mass of 13.64 ± 0.79 M⊕, it is in circular orbit at 0.119 ± 0.002 AU from its parent star, and lies inside the inner boundary of the habitable zone around its parent star.
Acceso Abierto
HADES RV programme with HARPS-N at TNG XIV. A candidate super-Earth orbiting the M-dwarf GJ 9689 with a period close to half the stellar rotation period
(EDP Sciences, 2021-07-12) Maldonado, J.; Petralia, A.; Damasso, M.; Pinamonti, M.; Scandariato, G.; González Álvarez, E.; Affer, L.; Micela, G.; Lanza, A. F.; Leto, G.; Poretti, E.; Sozzetti, A.; Perger, M.; Giacobbe, P.; Zanmar Sánchez, R.; Maggio, A.; Rebolo, R.; Ribas, I.; Suárez Mascareño, A.; Toledo Padrón, B.; Bignamini, A.; Molinari, E.; Covino, E.; Claudi, R.; Desidera, S.; Herrero, E.; Morales, J. C.; Pagano, I.; Piotto, G.; González Hernández, Carmen; Agencia Estatal de Investigación (AEI); Generalitat de Catalunya; Maldonado, J. [0000-0002-2218-5689]; Petralia, A. [0000-0002-9882-1020]; Damasso, M. [0000-0001-9984-4278]; Pinamonti, M. [0000-0002-4445-1845]; Affer, L. [0000-0001-5600-3778]; Lanza, A. F. [0000-0001-5928-7251]; Leto, G. [0000-0002-0040-5011]; Poretti, E. [0000-0003-1200-0473]; Sozzetti, A. [0000-0002-7504-365X]; Perger, M. [0000-0001-7098-0372]; Zanmar Sánchez, R. [0000-0002-6997-0887]; Maggio, A. [0000-0001-5154-6108]; González Hernández, J. I. [0000-0002-0264-7356]; Ribas, I. [0000-0002-6689-0312]; Toledo Padrón, B. [0000-0002-8194-215X]; Bignamini, A. [0000-0002-5606-6354]; Molinari, E. [0000-0002-1742-7735]; Covino, E. [0000-0002-7579-2298]; Claudi, R. [0000-0001-7707-5105]; Desidera, S. [0000-0001-8613-2589]
Context. It is now well-established that small, rocky planets are common around low-mass stars. However, the detection of such planets is challenged by the short-term activity of host stars. Aims. The HARPS-N red Dwarf Exoplanet Survey programme is a long-term project at the Telescopio Nazionale Galileo aimed at monitoring nearby, early-type, M dwarfs, using the HARPS-N spectrograph to search for small, rocky planets. Methods. A total of 174 HARPS-N spectroscopic observations of the M0.5V-type star GJ 9689 taken over the past seven years have been analysed. We combined these data with photometric measurements to disentangle signals related to the stellar activity of the star from possible Keplerian signals in the radial velocity data. We ran an MCMC analysis, applying Gaussian process regression techniques to model the signals present in the data. Results. We identify two periodic signals in the radial velocity time series, with periods of 18.27 and 39.31 d. The analysis of the activity indexes, photometric data, and wavelength dependency of the signals reveals that the 39.31 d signal corresponds to the stellar rotation period. On the other hand, the 18.27 d signal shows no relation to any activity proxy or the first harmonic of the rotation period. We, therefore, identify it as a genuine Keplerian signal. The best-fit model describing the newly found planet, GJ 9689 b, corresponds to an orbital period of Pb = 18.27 ± 0.01 d and a minimum mass of MP sini = 9.65 ± 1.41 M⊕.
Acceso Abierto
K2-111: an old system with two planets in near-resonance.
(Oxford Academics: Blackwell Publishing, 2020-10-27) Mortier, A.; Zapatero Osorio, M. R.; Malavolta, L.; Alibert, Y.; Rice, K.; Lillo Box, J.; Vanderburg, A.; Oshagh, M.; Buchhave, L. A.; Adibekyan, V.; Delgado Mena, E.; López Morales, M.; Charbonneau, D.; Sousa, S. G.; Lovis, C.; After, L.; Allende Prieto, C.; Barros, S. C. C.; Benatti, S.; Bonomo, A. S.; Boschin, W.; Bouchy, F.; Cabral, A.; Collier Cameron, A.; Cosentino, R.; Cristiani, S.; Demangeon, O. D. S.; Di Marcantonio, P.; D´Odorico, V.; Dumusque, X.; Ehrenreich, D.; Figueira, P.; Fiorenzano, A. F. M.; Ghedina, A.; Haldemann, J.; Harutyunyan, A.; Haywood, R. D.; Latham, D. W.; Lavie, B.; Lo Curto, G.; Maldonado, J.; Menescau, A.; Martins, C. J. A. P.; Mayor, M.; Mégevand, D.; Mehner, A.; Micela, G.; Molaro, P.; Molinari, E.; Nunes, N. J.; Pepe, F. A.; Pallé, E.; Phillips, D.; Piotto, G.; Pinamonti, M.; Poretti, E.; Rivas, M.; Rebolo, R.; Santos, N. C.; Sasselov, D.; Sozzetti, A.; Suárez Mascareño, A.; Udry, S.; West, R. G.; Watson, C. A.; Wilson, T. G.; González Hernández, Carmen; Science and Technology Facilities Council (STFC); Istituto Nazionale di Astrofisica (INAF); Swiss National Science Foundation (SNSF); Fundação para a Ciência e a Tecnologia (FCT); National Aeronautics and Space Administration (NASA); European Research Council (ERC); 0000-0002-9433-871X; 0000-0002-3814-5323; 0000-0002-0571-4163; 0000-0003-4434-2195; 0000-0003-1605-5666; 0000-0001-7246-5438; 0000-0003-2434-3625; 0000-0003-1231-2389; 0000-0003-1784-1431; 0000-0002-7504-365X; 0000-0002-0601-6199; 0000-0001-8749-1962; 0000-0002-8863-7828; 0000-0003-4422-2919; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
This paper reports on the detailed characterization of the K2-111 planetary system with K2, WASP, and ASAS-SN photometry, as well as high-resolution spectroscopic data from HARPS-N and ESPRESSO. The host, K2-111, is confirmed to be a mildly evolved (log g = 4.17), iron-poor ([Fe/H]=-0.46), but alpha-enhanced ([alpha/Fe]=0.27), chromospherically quiet, very old thick disc G2 star. A global fit, performed by using PyORBIT, shows that the transiting planet, K2-111 b, orbits with a period P-b = 5.3518 +/- 0.0004 d and has a planet radius of 1.82(-0.09)(+0.11) R-circle plus and a mass of 5.29(-0.77)(+0.76) M-circle plus, resulting in a bulk density slightly lower than that of the Earth. The stellar chemical composition and the planet properties are consistent with K2-111 b being a terrestrial planet with an iron core mass fraction lower than the Earth. We announce the existence of a second signal in the radial velocity data that we attribute to a non-transiting planet, K2-111 c, with an orbital period of 15.6785 +/- 0.0064 d, orbiting in near-3:1 mean motion resonance with the transiting planet, and a minimum planet mass of 11.3 +/- 1.1M(circle plus). Both planet signals are independently detected in the HARPS-N and ESPRESSO data when fitted separately. There are potentially more planets in this resonant system, but more well-sampled data are required to confirm their presence and physical parameters.
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.; Schrader, J. R.; Scholz, A.; Watkins, C.; Maillard, J. P.; Abreu, M.; Glasse, A.; Testi, L.; Doel, P.; Magnes, W.; Licandro Goldaracena, J.; Wawer, P.; Zapatero Osorio, M. R.; Decin, L.; Sánz Forcada, J.; Vakili, F.; Aylward, A.; Swain, M.; Sozzetti, A.; Filacchione, G.; Delgado Mena, E.; Read, P.; Lognonné, P.; Irshad, R.; Coates, A.; Cecchi Pestellini, C.; Thrastarson, H.; Brown, L.; Guillot, T.; Strazzulla, G.; Barstow, J. K.; Budaj, J.; Morgante, G.; Pietrzak, R.; Leconte, J.; Hersant, F.; De Sio, A.; Grassi, D.; Selsis, F.; Jarchow, C.; Fouqué, P.; Del Vecchio, C.; Tennyson, J.; Cassan, A.; Fernández Hernández, Maite; Burleigh, M. R.; Cordier, D.; De Witt, J.; Pagano, I.; Ray, T.; Gambicorti, L.; Palla, F.; Maldonado, J.; Biondi, D.; Eiroa, C.; Winek, W.; Ade, P.; Villaver, E.; Temple, J.; Gear, W.; Thompson, S.; Dominic, C.; Galand, M.; Focardi, M.; Cockell, C.; Pace, E.; Dorfi, E.; Bryson, I.; Cavarroc, C.; Pilat Lohinger, E.; Smith, A.; Eymet, V.; MacTavish, C.; Morales, J. C.; Gómez, H.; Stamper, R.; Esposito, M.; Andersen, A.; Azzollini, R.; Maxted, P.; Allende Prieto, C.; Nelson, R.; Gillon, M.; Achilleos, N.; Buchhave, L. A.; Fabrizio, N.; Ciaravella, A.; Claudi, R.; Damasso, M.; Bordé, P.; Figueira, P.; Rickman, H.; Rees, J. M.; Sitek, P.; Fossey, S.; Bakos, G.; Pascale, E.; Laken, B.; Soret, L.; Femenía Castella, B.; Allard, F.; Amado, P. J.; Luzzi, D.; Colomé, J.; Galand, M.; Lammer, H.; Bonford, B.; López Valverde, M. A.; Kerins, E.; Yung, Y.; Espinoza Contreras, M.; Irwin, P.; Herrero, E.; Wright, G.; Guàrdia, J.; Banaszkiewicz, M.; Hoogeeven, R.; Alcala, J.; Guio, P.; Koskinen, T.; Barton, E. J.; Piskunov, N.; Maurin, A. S.; Leto, G.; Boisse, I.; Claret, A.; Massi, F.; Kervella, P.; Börne, P.; Heiter, U.; Hargrave, P.; Fletcher, L.; Sánchez Béjar, V. J.; Bézard, B.; Cabral, A.; Michaut, C.; Winter, B.; Sousa, S.; Giuranna, M.; Batista, V.; Frith, J.; Ballerini, P.; López Morales, M.; Monteiro, M.; Tingley, B. W.; Lanza, N.; Maggio, A.; Lundgaard Rasmussen, I.; Altieri, F.; Covino, E.; Coustenis, A.; Heredero, R. L.; Watson, D.; Coudé du Foresto, V.; Liu, S. J.; Sicardy, B.; Deeg, H. J.; Moses, J.; Rodler, F.; Lithgow Bertelloni, C.; Demangeon, O.; Adybekian, V.; Fletcher, L.; Swinyard, B.; Morales Calderón, M.; Fouqué, P.; Deroo, P.; Lo Cicero, Ugo; Hueso, R.; Iro, N.; González Merino, B.; López Puertas, M.; Capria, M. T.; Danielski, C.; Branduardi Raymont, G.; Luntzer, A.; Gaulme, P.; Bulgarelli, A.; Parmentier, V.; Gerard, J. C.; Alard, C.; Frith, J.; Dobrijévic, M.; Medvedev, A.; Barrado, D.; Jacquemoud, S.; Sethenadh, J.; Readorn, K.; Polichtchouk, I.; Petrov, R.; García Piquer, A.; Tabernero, H. M.; White, G.; Pancrazzi, M.; García López, Ramón; Filacchione, G.; Gómez Leal, I.; Rengel, M.; Gesa, L.; Tanga, P.; Mueller Wodarg, I.; Israelian, G.; Rebolo López, R.; Shore, S.; Peralta, J.; Collura, A.; Giro, E.; Del Val Borro, M.; Griffith, C.; Tecsa, M.; Haigh, J.; Moro Martín, A.; Jones, H.; Gizon, L.; Pezzuto, S.; Giani, E.; Mall, U.; Eales, S.; Graczyk, R.; Ramos Zapata, G.; Krupp, N.; Sánchez Lavega, A.; Fossey, S.; Alonso Floriano, F. J.; Justtanot, K.; Santos, N.; Pérez Hoyos, S.; Savini, G.; Chamberlain, S.; Bowles, N.; Kerschbaum, F.; Tozzi, A.; Turrini, D.; Kipping, D.; Maruquette, J. B.; Correira, A.; Trifoglio, M.; Agúndez, Marcelino; Scandaratio, G.; Snellen, I. A.; Scuderi, S.; Femenía Castella, B.; Prisinzano, L.; Oliva, E.; Hébrard, E.; Lodieu, N.; Forget, F.; Chadney, J.; Showman, A.; Gustin, J.; Vinatier, S.; Charnoz, S.; Affer, L.; Rank Lüftinger, T.; Poretti, E.; Lahav, O.; North, C.; Gerard, J. C.; Murgas Alcaino, F.; Yurchenko, S. N.; Widemann, T.; Ward Thompson, D.; Montañés Rodríguez, P.; Kovács, G.; Valdivieso, M. L.; Moya Bedon, A.; Montalto, M.; Christian Jessen, N.; Venot, O.; Koskinen, T.; Lagage, P. O.; Bellucci, G.; Prinja, R.; Pinfield, D.; Banaszkiewicz, M.; Waldmann, I.; Jones, G.; Morello, G.; Crook, J.; Lim, T.; Parviainen, H.; Pallé, E.; Ramos, A. A.; Sanromá, E.; Waters, R.; Morais, H.; Stiepen, A.; Lellouch, E.; Orton, G.; Rezac, L.; Beaulieu, J. P.; Focardi, M.; Mauskopf, P.; Barlow, M.; Guedel, M.; Waltham, D.; Agnor, C.; Encrenaz, T.; Cerulli, R.; Balado, A.; Bouy, H.; Rebordao, J.; Stolarski, M.; Álvarez Iglesias, C. A.; Adriani, A.; Rocchetto, M.; Norgaard Nielsen, H. U.; Hollis, M.; Selig, A.; Malaguti, G.; Burston, R.; Peña Ramírez, K. Y.; Schmider, F. X.; Baffa, C.; Heyrovsky, D.; Figueira, P.; Piccioni, G.; Ottensamer, R.; Radioti, A.; Yelle, R.; Pantin, E.; Miles Paez, P.; Belmonte Avilés, J. A.; Montes, D.; Varley, R.; Viti, S.; Abe, L.; Pinsard, F.; Tessenyi, M.; Di Giorgio, A.; Turrini, D.; Terenzi, L.; Hubert, B.; Griffin, M.; Barber, R. J.; Cole, R.; Gianotti, F.; Blecka, M.; Wawrzaszk, A.; Middleton, K.; De Kok, R.; Martín Torres, Javier; Kehoe, T.; Cho, J.; Machado, P.; Berry, D.; Wisniowski, T.; Grodent, D.; Rataj, M.; Hornstrup, A.; Kerschbaum, F.; Vandenbussche, B.; Stixrude, L.; González Hernández, Carmen; 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]; Bulgarelli, A. [0000-0001-6347-0649]; Morales Calderon, M. [0000-0001-9526-9499]; Ward Thompson, D. [0000-0003-1140-2761]; Rebolo, R. [0000-0003-3767-7085]; López Valverde, M. A. [0000-0002-7989-4267]; Gillon, M. [0000-0003-1462-7739]; Morgante, G. [0000-0001-9234-7412]; Pena Ramírez, K. [0000-0002-5855-401X]; Galand, M. [0000-0001-5797-914X]; Pancrazzi, M. [0000-0002-3789-2482]; Pilat Lohinger, E. [0000-0002-5292-1923]; Altieri, F. [0000-0002-6338-8300]; Malaguti, G. [0000-0001-9872-3378]; Sánchez Lavega, A. [0000-0001-7234-7634]; Waldmann, I. [0000-0002-4205-5267]; Kovacs, G. [0000-0002-2365-2330]; Guillot, T. [0000-0002-7188-8428]; Monteiro, M. [0000-0001-5644-0898]; Bellucci, G. [0000-0003-0867-8679]; Baffa, C. [0000-0002-4935-100X]; Olivia, E. [0000-0002-9123-0412]; Tizzi, A. [0000-0002-6725-3825]; Selsis, F. [0000-0001-9619-5356]; Scuderi, Salvatore [0000-0002-8637-2109]; Hersant, F. [0000-0002-2687-7500]; Gear, W. [0000-0001-6789-6196]; Damasso, M. [0000-0001-9984-4278]; Irwin, P. [0000-0002-6772-384X]; Pinfield, D. [0000-0002-7804-4260]; Kipping, D. [0000-0002-4365-7366]; Maldonado, J. [0000-0002-4282-1072]; Pace, E. [0000-0001-5870-1772]; Burleigh, M. [0000-0003-0684-7803]; Chadney, J. [0000-0002-5174-2114]; Moro Martín, A. [0000-0001-9504-8426]; Claret, A. [0000-0002-4045-8134]; Rodríguez, P. [0000-0002-6855-9682]; Bezard, B. [0000-0002-5433-5661]; Gómez, H. [0000-0003-3398-0052]; Maldonado, J. [0000-0002-2218-5689]; Michaut, C. [0000-0002-2578-0117]; Hornstrup, A. [0000-0002-3363-0936]; Scholz, A. [0000-0001-8993-5053]; Sánchez Bejar, V. [0000-0002-5086-4232]; López Heredero, R. [0000-0002-2197-8388]; Sanz Forcada, J. [0000-0002-1600-7835]; Danielski, C. [0000-0002-3729-2663]; Vandenbussche, B. [0000-0002-1368-3109]; Sousa, S. [0000-0001-9047-2965]; Medved, A. [0000-0003-2713-8977]; Tinetti, G. [0000-0001-6058-6654]; Bakos, G. [0000-0001-7204-6727]; Ade, P. [0000-0002-5127-0401]; Amado, P. J. [0000-0002-8388-6040]; Martín Torres, J. [0000-0001-6479-2236]; Correira, A. [0000-0002-8946-8579]; Haigh, J. [0000-0001-5504-4754]; Scandariato, G. [0000-0003-2029-0626]; Guedel, M. [0000-0001-9818-0588]; Piskunov, N. [0000-0001-5742-7767]; Adibekyan, V. [0000-0002-0601-6199]; Pérez Hoyos, S. [0000-0001-9797-4917]; Poretti, E. [0000-0003-1200-0473]; Maggio, A. [0000-0001-5154-6108]; Kervella, P. [0000-0003-0626-1749]; Pascale, E. [0000-0002-3242-8154]; Claudi, R. [0000-0001-7707-5105]; Filacchione, G. [0000-0001-9567-0055]; Rickman, H. [0000-0002-9603-6619]; Sanroma, E. [0000-0001-8859-7937]; Agundez, M. [0000-0003-3248-3564]; Montes, D. [0000-0002-7779-238X]; Fletcher, L. [0000-0001-5834-9588]; Rataj, M. [0000-0002-2978-9629]; Stixrude, L. [0000-0003-3778-2432]; Montes, D. [0000-0002-7779-238X]; Morais, M. H. [0000-0001-5333-2736]; Hueso, R. [0000-0003-0169-123X]; Yurchenko, S. [0000-0001-9286-9501]; Morales, J. C. [0000-0003-0061-518X]; Pérez Hoyos, S. [0000-0002-2587-4682]; Santos, N. [0000-0003-4422-2919]; Peralta, J. [0000-0002-6823-1695]; Budaj, J. [0000-0002-9125-7340]; Barlow, M. [0000-0002-3875-1171]; Deeg, H. [0000-0003-0047-4241]; Grassi, D. [0000-0003-1653-3066]; Piccioni, G. [0000-0002-7893-6808]; Barton, E. [0000-0001-5945-9244]; Abreu, M. [0000-0002-0716-9568]; Ribas, I. [0000-0002-6689-0312]; Coates, A. [0000-0002-6185-3125]; García Ramón, J. [0000-0002-8204-6832]; Bouy, H. [0000-0002-7084-487X[; Lognonne, P. [0000-0002-1014-920X]; Demangeon, O. [0000-0001-7918-0355]; Ray, T. [0000-0002-2110-1068]; Guio, P. [0000-0002-1607-5862]; Tanga, P. [0000-0002-2718-997X]; Delgado, M. E. [0000-0003-4434-2195]; Leto, G. [0000-0002-0040-5011]; Prisinzano, L. [0000-0002-8893-2210]; Barstow, J. [0000-0003-3726-5419]; Balado, A. [0000-0003-4268-2516]; Lithgow Bertelloni, C. [0000-0003-0924-6587]; Zapatero Osorio, M. R. [0000-0001-5664-2852]; Affer, L. [0000-0001-5600-3778]; Ciaravella, A. [0000-0002-3127-8078]; Barrado Navascues, D. [0000-0002-5971-9242]; Figueira, P. [0000-0001-8504-283X]; Covino, E. [0000-0002-6187-6685]; Venot, O. [0000-0003-2854-765X]; Cabral, A. [0000-0002-9433-871X]; Watson, D. [0000-0002-4465-8264]; Turrini, D. [0000-0002-1923-7740]
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.
Acceso Abierto
The GAPS Programme at TNG XXI. A GIARPS case study of known young planetary candidates: confirmation of HD 285507 b and refutation of AD Leonis b
(EDP Sciences, 2020-05-29) Carleo, I.; Malavolta, L.; Lanza, A. F.; Damasso, M.; Desidera, S.; Borsa, F.; Mallonn, M.; Pinamonti, M.; Gratton, R.; Alei, E.; Benatti, S.; Mancini, L.; Maldonado, J.; Biazzo, K.; Esposito, M.; Frustagli, G.; González Álvarez, E.; Micela, G.; Scandariato, G.; Sozzatti, A.; Affer, L.; Bignamini, A.; Bonomo, A. S.; Claudi, R.; Cosentino, R.; Covino, E.; Fiorenzano, A. F. M.; Giacobbe, P.; Harutyunyan, A.; Leto, G.; Maggio, A.; Molinari, E.; Nascimbeni, V.; Pagano, I.; Pedani, M.; Piotto, G.; Poretti, E.; Rainer, M.; Redfield, S.; Baffa, C.; Baruffolo, A.; Buschschacher, N.; Billoti, V.; Cecconi, M.; Falcini, G.; Fantinel, D.; Fini, L.; Galli, A.; Ghedina, A.; Ghinassi, F.; Giani, E.; Guerra, J.; Hernández Díaz, M.; Hernández, N.; Luzzolino, M.; Lodi, M.; Oliva, E.; Origlia, L.; Pérez Ventura, H.; Puglisi, A.; Riverol, C.; Riverol, L.; San Juan, J.; Sanna, N.; Scuderi, S.; Seemann, U.; Sozzi, M.; Tozzi, P.; González Hernández, Carmen; Jimeno González, María; Agenzia Spaziale Italiana (ASI); European Commission (EC); Claudi, R. [0000-0001-7707-5105]; Leto, G. [0000-0002-0040-5011]; Piotto, G. [0000-0002-9937-6387]; Bonomo, A. S. [0000-0002-6177-198X]; Sozzetti, A. [0000-0002-7504-365X]; Biazzo, K. [0000-0002-1892-2180]; Ghedina, A. [0000-0003-4702-5152]; Damasso, M. [0000-0001-9984-4278]; Cosentino, R. [0000-0003-1784-1431]; Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2017-0737
Context. The existence of hot Jupiters is still not well understood. Two main channels are thought to be responsible for their current location: a smooth planet migration through the protoplanetary disk or the circularization of an initial highly eccentric orbit by tidal dissipation leading to a strong decrease in the semimajor axis. Different formation scenarios result in different observable effects, such as orbital parameters (obliquity and eccentricity) or frequency of planets at different stellar ages. Aims. In the context of the GAPS Young Objects project, we are carrying out a radial velocity survey with the aim of searching and characterizing young hot-Jupiter planets. Our purpose is to put constraints on evolutionary models and establish statistical properties, such as the frequency of these planets from a homogeneous sample. Methods. Since young stars are in general magnetically very active, we performed multi-band (visible and near-infrared) spectroscopy with simultaneous GIANO-B + HARPS-N (GIARPS) observing mode at TNG. This helps in dealing with stellar activity and distinguishing the nature of radial velocity variations: stellar activity will introduce a wavelength-dependent radial velocity amplitude, whereas a Keplerian signal is achromatic. As a pilot study, we present here the cases of two known hot Jupiters orbiting young stars: HD 285507 b and AD Leo b. Results. Our analysis of simultaneous high-precision GIARPS spectroscopic data confirms the Keplerian nature of the variation in the HD 285507 radial velocities and refines the orbital parameters of the hot Jupiter, obtaining an eccentricity consistent with a circular orbit. Instead, our analysis does not confirm the signal previously attributed to a planet orbiting AD Leo. This demonstrates the power of the multi-band spectroscopic technique when observing active stars.