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201. The Pristine Inner Galaxy Survey (PIGS) VII: A discovery of the first inner Galaxy CEMP-r/s star

Author: Mashonkina, L, primary, Arentsen, A, additional, Aguado, D S, additional, Smogorzhevskii, A, additional, Hampel, M, additional, Karakas, A I, additional, Sestito, F, additional, Martin, N F, additional, Venn, K A, additional, and Hernández, J I González, additional
Published: 2023
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202. HD 23472: a multi-planetary system with three super-Earths and two potential super-Mercuries,

Author: Barros, S. C. C., primary, Demangeon, O. D. S., additional, Alibert, Y., additional, Leleu, A., additional, Adibekyan, V., additional, Lovis, C., additional, Bossini, D., additional, Sousa, S. G., additional, Hara, N., additional, Bouchy, F., additional, Lavie, B., additional, Rodrigues, J., additional, da Silva, J. Gomes, additional, Lillo-Box, J., additional, Pepe, F. A., additional, Tabernero, H. M., additional, Osorio, M. R. Zapatero, additional, Sozzetti, A., additional, Mascareño, A. Suárez, additional, Micela, G., additional, Prieto, C. Allende, additional, Cristiani, S., additional, Damasso, M., additional, Di Marcantonio, P., additional, Ehrenreich, D., additional, Faria, J., additional, Figueira, P., additional, Hernández, J. I. González, additional, Jenkins, J., additional, Lo Curto, G., additional, Martins, C. J. A. P., additional, Nunes, N. J., additional, Pallé, E., additional, Santos, N. C., additional, Rebolo, R., additional, Seager, S., additional, Twicken, J. D., additional, Udry, S., additional, Vanderspek, R., additional, and Winn, J. N., additional
Published: 2022
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203. A novel framework for semi-Bayesian radial velocities through template matching

Author: Silva, A. M., primary, Faria, J. P., additional, Santos, N. C., additional, Sousa, S. G., additional, Viana, P. T. P., additional, Martins, J. H. C., additional, Figueira, P., additional, Lovis, C., additional, Pepe, F., additional, Cristiani, S., additional, Rebolo, R., additional, Allart, R., additional, Cabral, A., additional, Mehner, A., additional, Sozzetti, A., additional, Mascareño, A. Suárez, additional, Martins, C. J. A. P., additional, Ehrenreich, D., additional, Mégevand, D., additional, Palle, E., additional, Curto, G. Lo, additional, Tabernero, H. M., additional, Lillo-Box, J., additional, Hernández, J. I. González, additional, Osorio, M. R. Zapatero, additional, Hara, N. C., additional, Nunes, N. J., additional, Di Marcantonio, P., additional, Udry, S., additional, Adibekyan, V., additional, and Dumusque, X., additional
Published: 2022
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204. The polar orbit of the warm Neptune GJ 436b seen with VLT/ESPRESSO

Author: Bourrier, V., primary, Zapatero Osorio, M. R., additional, Allart, R., additional, Attia, O., additional, Cretignier, M., additional, Dumusque, X., additional, Lovis, C., additional, Adibekyan, V., additional, Borsa, F., additional, Figueira, P., additional, Hernández, J. I. González, additional, Mehner, A., additional, Santos, N. C., additional, Schmidt, T., additional, Seidel, J. V., additional, Sozzetti, A., additional, Alibert, Y., additional, Casasayas-Barris, N., additional, Ehrenreich, D., additional, Lo Curto, G., additional, Martins, C. J. A. P., additional, Di Marcantonio, P., additional, Mégevand, D., additional, Nunes, N. J., additional, Palle, E., additional, Poretti, E., additional, and Sousa, S. G., additional
Published: 2022
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205. Fundamental physics with ESPRESSO: Constraints on Bekenstein and dark energy models from astrophysical and local probes

Author: Martins, C. J. A. P., primary, Cristiani, S., additional, Cupani, G., additional, D’Odorico, V., additional, Santos, R. Génova, additional, Leite, A. C. O., additional, Marques, C. M. J., additional, Milaković, D., additional, Molaro, P., additional, Murphy, Michael T., additional, Nunes, N. J., additional, Schmidt, Tobias M., additional, Adibekyan, V., additional, Alibert, Y., additional, Di Marcantonio, Paolo, additional, Hernández, J. I. González, additional, Mégevand, D., additional, Palle, E., additional, Pepe, F. A., additional, Santos, N. C., additional, Sousa, S. G., additional, Sozzetti, A., additional, Mascareño, A. Suárez, additional, and Osorio, M. R. Zapatero, additional
Published: 2022
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206. ANDES, the high resolution spectrograph for the ELT: science case, baseline design and path to construction

Author: Evans, Christopher J., Bryant, Julia J., Motohara, Kentaro, Marconi, A., Abreu, M., Adibekyan, V., Alberti, V., Albrecht, S., Alcaniz, J., Aliverti, M., Prieto, C. Allende, Gómez, J. D. Alvarado, Amado, P. J., Amate, M., Andersen, M. I., Artigau, E., Baker, C., Baldini, V., Balestra, A., Barnes, S. A., Baron, F., Barros, S. C. C., Bauer, S. M., Beaulieu, M., Bellido-Tirado, O., Benneke, B., Bensby, T., Bergin, E. A., Biazzo, K., Bik, A., Birkby, J. L., Blind, N., Boisse, I., Bolmont, E., Bonaglia, M., Bonfils, X., Borsa, F., Brandeker, A., Brandner, W., Broeg, C. H., Brogi, M., Brousseau, D., Brucalassi, A., Brynnel, J., Buchhave, L. A., Buscher, D. F., Cabral, A., Calderone, G., Calvo-Ortega, R., Martins, B. L. Canto, Cantalloube, F., Carbonaro, L., Chauvin, G., Chazelas, B., Cheffot, A.-L., Cheng, Y. S., Chiavassa, A., Christensen, L., Cirami, R., Cook, N. J., Cooke, R. J., Coretti, I., Covino, S., Cowan, N., Cresci, G., Cristiani, S., Parro, V. Cunha, Cupani, G., D'Odorico, V., Leão, I. de Castro, Cia, A. De, Medeiros, J. R. De, Debras, F., Debus, M., Demangeon, O., Dessauges-Zavadsky, M., Marcantonio, P. Di, Dionies, F., Doyon, R., Dunn, J., Ehrenreich, D., Faria, J. P., Feruglio, C., Fisher, M., Fontana, A., Fumagalli, M., Fusco, T., Fynbo, J., Gabella, O., Gaessler, W., Gallo, E., Gao, X., Genolet, L., Genoni, M., Giacobbe, P., Giro, E., Gonçalves, R. S., Gonzalez, O., Hernández, J. I. González, Témich, F. Gracia, Haehnelt, M. G., Haniff, C., Hatzes, A., Helled, R., Hoeijmakers, H.J., Huke, P., Järvinen, S., Järvinen, A., Kaminski, A., Korn, A., Kouach, D., Kowzan, G., Kreidberg, L., Landoni, M., Lanotte, A., Lavail, A., Li, J., Liske, J., Lovis, C., Lucatello, S., Lunney, D., MacIntosh, M., Madhusudhan, N., Magrini, L., Maiolino, R., Malo, L., Man, A., Marquart, T., Marques, E. L., Martins, A. M., Martins, C. J. A. P., Maslowski, P., Mason, C., Mason, E., McCracken, R. A., Mergo, P., Micela, G., Mitchell, T., Mollière, P., Monteiro, M., Montgomery, D., Mordasini, C., Morin, J., Mucciarelli, A., Murphy, M. T., N'Diaye, M., Neichel, B., Niedzielski, A. T., Niemczura, E., Nortmann, L., Noterdaeme, P., Nunes, N., Oggioni, L., Oliva, E., Önel, H., Origlia, L., Östlin, G., Palle, E., Papaderos, P., Pariani, G., Castro, J. Peñate, Pepe, F., Levasseur, L. Perreault, Petit, P., Pino, L., Piqueras, J., Pollo, A., Poppenhaeger, K., Quirrenbach, A., Rauscher, E., Rebolo, R., Redaelli, E. M. A., Reffert, S., Reid, D. T., Reiners, A., Richter, P., Riva, M., Rivoire, S., Rodríguez-López, C., Roederer, I. U., Romano, D., Rousseau, S., Rowe, J., Salvadori, S., Santos, N., Diaz, P. Santos, Sanz-Forcada, J., Sarajlic, M., Sauvage, J.-F., Schäfer, S., Schiavon, R. P., Schmidt, T. M., Selmi, C., Sivanandam, S., Sordet, M., Sordo, R., Sortino, F., Sosnowska, D., Sousa, S. G., Stempels, E., Strassmeier, K. G., Mascareño, A. Suárez, Sulich, A., Sun, X., Tanvir, N.R., Tenegi-Sanginés, F., Thibault, S., Thompson, S. J., Tozzi, A., Turbet, M., Vallée, P., Varas, R., Venn, K., Véran, J.-P., Verma, A., Viel, M., Wade, G., Waring, C., Weber, M., Weder, J., Wehbe, B., Weingrill, J., Woche, M., Xompero, M., Zackrisson, E., Zanutta, A., Osorio, M. R. Zapatero, Zechmeister, M., Zimara, J., Evans, Christopher J., Bryant, Julia J., Motohara, Kentaro, Marconi, A., Abreu, M., Adibekyan, V., Alberti, V., Albrecht, S., Alcaniz, J., Aliverti, M., Prieto, C. Allende, Gómez, J. D. Alvarado, Amado, P. J., Amate, M., Andersen, M. I., Artigau, E., Baker, C., Baldini, V., Balestra, A., Barnes, S. A., Baron, F., Barros, S. C. C., Bauer, S. M., Beaulieu, M., Bellido-Tirado, O., Benneke, B., Bensby, T., Bergin, E. A., Biazzo, K., Bik, A., Birkby, J. L., Blind, N., Boisse, I., Bolmont, E., Bonaglia, M., Bonfils, X., Borsa, F., Brandeker, A., Brandner, W., Broeg, C. H., Brogi, M., Brousseau, D., Brucalassi, A., Brynnel, J., Buchhave, L. A., Buscher, D. F., Cabral, A., Calderone, G., Calvo-Ortega, R., Martins, B. L. Canto, Cantalloube, F., Carbonaro, L., Chauvin, G., Chazelas, B., Cheffot, A.-L., Cheng, Y. S., Chiavassa, A., Christensen, L., Cirami, R., Cook, N. J., Cooke, R. J., Coretti, I., Covino, S., Cowan, N., Cresci, G., Cristiani, S., Parro, V. Cunha, Cupani, G., D'Odorico, V., Leão, I. de Castro, Cia, A. De, Medeiros, J. R. De, Debras, F., Debus, M., Demangeon, O., Dessauges-Zavadsky, M., Marcantonio, P. Di, Dionies, F., Doyon, R., Dunn, J., Ehrenreich, D., Faria, J. P., Feruglio, C., Fisher, M., Fontana, A., Fumagalli, M., Fusco, T., Fynbo, J., Gabella, O., Gaessler, W., Gallo, E., Gao, X., Genolet, L., Genoni, M., Giacobbe, P., Giro, E., Gonçalves, R. S., Gonzalez, O., Hernández, J. I. González, Témich, F. Gracia, Haehnelt, M. G., Haniff, C., Hatzes, A., Helled, R., Hoeijmakers, H.J., Huke, P., Järvinen, S., Järvinen, A., Kaminski, A., Korn, A., Kouach, D., Kowzan, G., Kreidberg, L., Landoni, M., Lanotte, A., Lavail, A., Li, J., Liske, J., Lovis, C., Lucatello, S., Lunney, D., MacIntosh, M., Madhusudhan, N., Magrini, L., Maiolino, R., Malo, L., Man, A., Marquart, T., Marques, E. L., Martins, A. M., Martins, C. J. A. P., Maslowski, P., Mason, C., Mason, E., McCracken, R. A., Mergo, P., Micela, G., Mitchell, T., Mollière, P., Monteiro, M., Montgomery, D., Mordasini, C., Morin, J., Mucciarelli, A., Murphy, M. T., N'Diaye, M., Neichel, B., Niedzielski, A. T., Niemczura, E., Nortmann, L., Noterdaeme, P., Nunes, N., Oggioni, L., Oliva, E., Önel, H., Origlia, L., Östlin, G., Palle, E., Papaderos, P., Pariani, G., Castro, J. Peñate, Pepe, F., Levasseur, L. Perreault, Petit, P., Pino, L., Piqueras, J., Pollo, A., Poppenhaeger, K., Quirrenbach, A., Rauscher, E., Rebolo, R., Redaelli, E. M. A., Reffert, S., Reid, D. T., Reiners, A., Richter, P., Riva, M., Rivoire, S., Rodríguez-López, C., Roederer, I. U., Romano, D., Rousseau, S., Rowe, J., Salvadori, S., Santos, N., Diaz, P. Santos, Sanz-Forcada, J., Sarajlic, M., Sauvage, J.-F., Schäfer, S., Schiavon, R. P., Schmidt, T. M., Selmi, C., Sivanandam, S., Sordet, M., Sordo, R., Sortino, F., Sosnowska, D., Sousa, S. G., Stempels, E., Strassmeier, K. G., Mascareño, A. Suárez, Sulich, A., Sun, X., Tanvir, N.R., Tenegi-Sanginés, F., Thibault, S., Thompson, S. J., Tozzi, A., Turbet, M., Vallée, P., Varas, R., Venn, K., Véran, J.-P., Verma, A., Viel, M., Wade, G., Waring, C., Weber, M., Weder, J., Wehbe, B., Weingrill, J., Woche, M., Xompero, M., Zackrisson, E., Zanutta, A., Osorio, M. R. Zapatero, Zechmeister, M., and Zimara, J.
Abstract: The first generation of ELT instruments includes an optical-infrared high resolution spectrograph, indicated as ELT-HIRES and recently christened ANDES (ArmazoNes high Dispersion Echelle Spectrograph). ANDES consists of three fibre-fed spectrographs (UBV, RIZ, YJH) providing a spectral resolution of ∼100,000 with a minimum simultaneous wavelength coverage of 0.4-1.8 µm with the goal of extending it to 0.35-2.4 µm with the addition of a K band spectrograph. It operates both in seeing- and diffraction-limited conditions and the fibre-feeding allows several, interchangeable observing modes including a single conjugated adaptive optics module and a small diffraction-limited integral field unit in the NIR. Its modularity will ensure that ANDES can be placed entirely on the ELT Nasmyth platform, if enough mass and volume is available, or partly in the Coudé room. ANDES has a wide range of groundbreaking science cases spanning nearly all areas of research in astrophysics and even fundamental physics. Among the top science cases there are the detection of biosignatures from exoplanet atmospheres, finding the fingerprints of the first generation of stars, tests on the stability of Nature’s fundamental couplings, and the direct detection of the cosmic acceleration. The ANDES project is carried forward by a large international consortium, composed of 35 Institutes from 13 countries, forming a team of more than 200 scientists and engineers which represent the majority of the scientific and technical expertise in the field among ESO member states.
Published: 2022

207. The polar orbit of the warm Neptune GJ 436b seen with VLT/ESPRESSO

Author: Bourrier, V., Zapatero Osorio, M. R., Allart, R., Attia, O., Cretignier, M., Dumusque, X., Lovis, C., Adibekyan, V., Borsa, F., Figueira, P., Hernández, J. I. González, Mehner, A., Santos, N. C., Schmidt, T., Seidel, J. V., Sozzetti, A., Alibert, Y., Casasayas-Barris, N., Ehrenreich, D., Lo Curto, G., Martins, C. J. A. P., Di Marcantonio, P., Mégevand, D., Nunes, N. J., Palle, E., Poretti, E., and Sousa, S. G.
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Planets and satellites - individual - GJ436b, Astrophysics - earth and planetary astrophysics, 530 Physics, Space and Planetary Science, 520 Astronomy, Techniques - spectroscopic, FOS: Physical sciences, Astronomy and Astrophysics, 620 Engineering, Methods - data analysis, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - solar and stellar astrophysics
Abstract: GJ436b might be the prototype of warm Neptunes that have undergone late migration induced by an outer companion. Precise determination of the orbital architecture of such systems is critical to constraining their dynamical history and evaluating the role of delayed migration in the exoplanet population. To this purpose we analyzed the Rossiter-McLaughlin (RM) signal of GJ436 b in two transits - recently observed with ESPRESSO - using three different techniques. The high level of precision achieved in radial velocity (RV) measurements allows us to detect the deviation from the Keplerian orbit, despite the slow rotation of the M dwarf host (vsini = 272.0+40.0-34.0 m/s), and to measure the sky-projected obliquity ($\lambda$ = 102.5+17.2-18.5$^{\circ}$). The Reloaded RM technique, which allows the stellar RV field along the transit chord to be analyzed, yields $\lambda$ = 107.5+23.6-19.3$^{\circ}$ and vsini = 292.9+41.9-49.9 m/s. The RM Revolutions technique, which allows us to fit the spectral profiles from all planet-occulted regions together, yields $\lambda$ = 114.1+22.8-17.8$^{\circ}$ and vsini = 300.5+45.9-57.0 m/s. The consistent results between these three techniques, and with published results from HARPS/HARPS-N data, confirm the polar orbit of GJ436b and support the hypothesis that its origin lies in Kozai migration. Results from a joint RM Revolutions analysis of the ESPRESSO, HARPS, and HARPS-N datasets ($\lambda$ = 113.5+23.3-17.3$^{\circ}$; vsini = 293.5+43.7-52.2 m/s) combined with a revised stellar inclination ($i_\star$ = 35.7+5.9-7.6$^{\circ}$ or 144.2+7.6-5.9$^{\circ}$) lead us to constrain the 3D obliquity $\Psi$ to 103.2+12.8-11.5$^{\circ}$., Comment: 10 pages, 9 figures, accepted for publication in A&A (27 January 2022)
Published: 2022

208. HD 23472: A multi-planetary system with three super-Earths and two potential super-Mercuries

Author: Barros, S. C. C., Demangeon, O. D. S., Alibert, Y., Leleu, A., Adibekyan, V., Lovis, C., Bossini, D., Sousa, S. G., Hara, N., Bouchy, F., Lavie, B., Rodrigues, J., da Silva, J. Gomes, Lillo-Box, J., Pepe, F. A., Tabernero, H. M., Osorio, M. R. Zapatero, Sozzetti, A., Mascareño, A. Suárez, Micela, G., Prieto, C. Allende, Cristiani, S., Damasso, M., Di Marcantonio, P., Ehrenreich, D., Faria, J., Figueira, P., Hernández, J. I. González, Jenkins, J., Lo Curto, G., Martins, C. J. A. P., Nunes, N. J., Pallé, E., Santos, N. C., Rebolo, R., Seager, S., Twicken, J. D., Udry, S., Vanderspek, R., and Winn, J. N.
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), 530 Physics, Space and Planetary Science, 520 Astronomy, FOS: Physical sciences, Astronomy and Astrophysics, 620 Engineering, Astrophysics - Earth and Planetary Astrophysics
Abstract: We report the characterisation of a multi-planetary system composed of five exoplanets orbiting the K-dwarf HD~23472 (TOI-174). In addition to the two super-Earths that were previously confirmed, we confirm and characterise three Earth-size planets in the system using ESPRESSO radial velocity observations. The planets of this compact system have periods of $P_d \sim 3.98\,$, $P_e \sim 7.90\,$, $P_f \sim 12.16\,$, $P_b \sim 17.67,\,$ and $P_c \sim 29.80\,$days and radii of $R_d \sim 0.75\,$ , $R_e \sim 0.82,$, $R_f \sim 1.13\,$, $R_b \sim 2.01,\,$ and, $R_c \sim 1.85\,$ \REarth. Because of its small size, its proximity to planet d's transit, and close resonance with planet d, planet e was only recently found. The planetary masses were estimated to be $M_d =0.54\pm0.22$, $M_e =0.76\pm0.30$, $M_f =0.64_{-0.39}^{+0.46}$, $M_b = 8.42_{-0.84}^{+0.83}$, and $M_c = 3.37_{-0.87}^{+0.92}$ \MEarth. These planets are among the lightest planets, with masses measured using the radial velocity method, demonstrating the very high precision of the ESPRESSO spectrograph. We estimated the composition of the system's five planets and found that their gas and water mass fractions increase with stellar distance, suggesting that the system was shaped by irradiation. The high density of the two inner planets ($\rho_d = 7.5_{-3.1}^{+3.9}$ and $\rho_e = 7.5_{-3.0}^{+3.9}\, \mathrm{g.cm^{-3}}$) indicates that they are likely to be super-Mercuries. This is supported by the modelling of the internal structures of the planets, which also suggests that the three outermost planets have significant water or gas content If the existence of two super-Mercuries in the system is confirmed, this system will be the only one known to feature two super-Mercuries, making it an excellent testing bed for theories of super-Mercuries formation. (Abridged), Comment: 24 pages, 13 figures, Published in A&A
Published: 2022
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209. A tale of two stellar characterisation codes: StePar and SteParSyn

Author: Tabernero, H. M., Montes, D., Marfil, E., and Hernández, J. I. González
Subjects: Post main sequence cool stars, Cool Stars on the main sequence, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: We report on two state-of-the-art codes designed to characterise the spectra of late-type stars. STEPAR is a Python 3.X code that implements the EW method to calculate stellar atmospheric parameters (Teff, log(g), and [Fe/H]) of FGK stars. This code has already been extensively used to analyse high-resolution stellar spectra of thousands of Gaia-ESO Survey stars, among others. On the other hand, STEPARSYN is a Bayesian code designed to retrieve the distribution of stellar parameters of an observed spectrum using the spectral synthesis method combined with a robust scheme that rests on a Markov Chain Monte Carlo sampler.
Published: 2021
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210. Atlas of Starburst Galaxies Observed from Canarias

Author: García, A. M. Pérez, primary, Hidalgo, P. Rodríguez, additional, Núñnez, M. J. Vidal, additional, Pulido, J. A. Acosta, additional, Lorenzo, B. García, additional, Melo, V. P., additional, Hernández, J. I. González, additional, Espinosa, J. M. Rodríguez, additional, Tuñín, C. Muñoz, additional, and Varela, A. M., additional
Published: 2003
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211. K2-111: an old system with two planets in near-resonance*

Author: Mortier, A, Zapatero Osorio, M R, Malavolta, L, Alibert, Y, Rice, K, Lillo-Box, J, Vanderburg, A, Oshagh, M, Buchhave, L, Adibekyan, V, Mena, E Delgado, Lopez-Morales, M, Charbonneau, D, Sousa, S G, Lovis, C, Affer, L, Prieto, C Allende, Barros, S C C, Benatti, S, Bonomo, A S, Boschin, W, Bouchy, F, Cabral, A, Cameron, A Collier, Cosentino, R, Cristiani, S, Demangeon, O D S, Marcantonio, P Di, D’Odorico, V, Dumusque, X, Ehrenreich, D, Figueira, P, Fiorenzano, A, Ghedina, A, Hernández, J I González, Haldemann, J, Harutyunyan, A, Haywood, R D, Latham, D W, Lavie, B, Curto, G Lo, Maldonado, J, Manescau, A, Martins, C J A P, Mayor, M, Mégevand, D, Mehner, A, Micela, G, Molaro, P, Molinari, E, Nunes, N J, Pepe, F A, Palle, E, Phillips, D, Piotto, G, Pinamonti, M, Poretti, E, Riva, M, Rebolo, R, Santos, N C, Sasselov, D, Sozzetti, A, Mascareño, A Suárez, Udry, S, West, R G, Watson, C A, Wilson, T G, Mortier, A, Zapatero Osorio, M R, Malavolta, L, Alibert, Y, Rice, K, Lillo-Box, J, Vanderburg, A, Oshagh, M, Buchhave, L, Adibekyan, V, Mena, E Delgado, Lopez-Morales, M, Charbonneau, D, Sousa, S G, Lovis, C, Affer, L, Prieto, C Allende, Barros, S C C, Benatti, S, Bonomo, A S, Boschin, W, Bouchy, F, Cabral, A, Cameron, A Collier, Cosentino, R, Cristiani, S, Demangeon, O D S, Marcantonio, P Di, D’Odorico, V, Dumusque, X, Ehrenreich, D, Figueira, P, Fiorenzano, A, Ghedina, A, Hernández, J I González, Haldemann, J, Harutyunyan, A, Haywood, R D, Latham, D W, Lavie, B, Curto, G Lo, Maldonado, J, Manescau, A, Martins, C J A P, Mayor, M, Mégevand, D, Mehner, A, Micela, G, Molaro, P, Molinari, E, Nunes, N J, Pepe, F A, Palle, E, Phillips, D, Piotto, G, Pinamonti, M, Poretti, E, Riva, M, Rebolo, R, Santos, N C, Sasselov, D, Sozzetti, A, Mascareño, A Suárez, Udry, S, West, R G, Watson, C A, and Wilson, T G
Abstract: This paper reports on the detailed characterisation 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 ([α/Fe]=0.27), chromospherically quiet, very old thick disc G2 star.
Published: 2020

212. A giant exoplanet orbiting a very-low-mass star challenges planet formation models

Author: Morales, J. C., primary, Mustill, A. J., additional, Ribas, I., additional, Davies, M. B., additional, Reiners, A., additional, Bauer, F. F., additional, Kossakowski, D., additional, Herrero, E., additional, Rodríguez, E., additional, López-González, M. J., additional, Rodríguez-López, C., additional, Béjar, V. J. S., additional, González-Cuesta, L., additional, Luque, R., additional, Pallé, E., additional, Perger, M., additional, Baroch, D., additional, Johansen, A., additional, Klahr, H., additional, Mordasini, C., additional, Anglada-Escudé, G., additional, Caballero, J. A., additional, Cortés-Contreras, M., additional, Dreizler, S., additional, Lafarga, M., additional, Nagel, E., additional, Passegger, V. M., additional, Reffert, S., additional, Rosich, A., additional, Schweitzer, A., additional, Tal-Or, L., additional, Trifonov, T., additional, Zechmeister, M., additional, Quirrenbach, A., additional, Amado, P. J., additional, Guenther, E. W., additional, Hagen, H.-J., additional, Henning, T., additional, Jeffers, S. V., additional, Kaminski, A., additional, Kürster, M., additional, Montes, D., additional, Seifert, W., additional, Abellán, F. J., additional, Abril, M., additional, Aceituno, J., additional, Aceituno, F. J., additional, Alonso-Floriano, F. J., additional, Ammler-von Eiff, M., additional, Antona, R., additional, Arroyo-Torres, B., additional, Azzaro, M., additional, Barrado, D., additional, Becerril-Jarque, S., additional, Benítez, D., additional, Berdiñas, Z. M., additional, Bergond, G., additional, Brinkmöller, M., additional, del Burgo, C., additional, Burn, R., additional, Calvo-Ortega, R., additional, Cano, J., additional, Cárdenas, M. C., additional, Guillén, C. Cardona, additional, Carro, J., additional, Casal, E., additional, Casanova, V., additional, Casasayas-Barris, N., additional, Chaturvedi, P., additional, Cifuentes, C., additional, Claret, A., additional, Colomé, J., additional, Czesla, S., additional, Díez-Alonso, E., additional, Dorda, R., additional, Emsenhuber, A., additional, Fernández, M., additional, Fernández-Martín, A., additional, Ferro, I. M., additional, Fuhrmeister, B., additional, Galadí-Enríquez, D., additional, Cava, I. Gallardo, additional, Vargas, M. L. García, additional, Garcia-Piquer, A., additional, Gesa, L., additional, González-Álvarez, E., additional, Hernández, J. I. González, additional, González-Peinado, R., additional, Guàrdia, J., additional, Guijarro, A., additional, de Guindos, E., additional, Hatzes, A. P., additional, Hauschildt, P. H., additional, Hedrosa, R. P., additional, Hermelo, I., additional, Arabi, R. Hernández, additional, Otero, F. Hernández, additional, Hintz, D., additional, Holgado, G., additional, Huber, A., additional, Huke, P., additional, Johnson, E. N., additional, de Juan, E., additional, Kehr, M., additional, Kemmer, J., additional, Kim, M., additional, Klüter, J., additional, Klutsch, A., additional, Labarga, F., additional, Labiche, N., additional, Lalitha, S., additional, Lampón, M., additional, Lara, L. M., additional, Launhardt, R., additional, Lázaro, F. J., additional, Lizon, J.-L., additional, Llamas, M., additional, Lodieu, N., additional, López del Fresno, M., additional, Salas, J. F. López, additional, López-Santiago, J., additional, Madinabeitia, H. Magán, additional, Mall, U., additional, Mancini, L., additional, Mandel, H., additional, Marfil, E., additional, Molina, J. A. Marín, additional, Martín, E. L., additional, Martín-Fernández, P., additional, Martín-Ruiz, S., additional, Martínez-Rodríguez, H., additional, Marvin, C. J., additional, Mirabet, E., additional, Moya, A., additional, Naranjo, V., additional, Nelson, R. P., additional, Nortmann, L., additional, Nowak, G., additional, Ofir, A., additional, Pascual, J., additional, Pavlov, A., additional, Pedraz, S., additional, Medialdea, D. Pérez, additional, Pérez-Calpena, A., additional, Perryman, M. A. C., additional, Rabaza, O., additional, Ballesta, A. Ramón, additional, Rebolo, R., additional, Redondo, P., additional, Rix, H.-W., additional, Rodler, F., additional, Trinidad, A. Rodríguez, additional, Sabotta, S., additional, Sadegi, S., additional, Salz, M., additional, Sánchez-Blanco, E., additional, Carrasco, M. A. Sánchez, additional, Sánchez-López, A., additional, Sanz-Forcada, J., additional, Sarkis, P., additional, Sarmiento, L. F., additional, Schäfer, S., additional, Schlecker, M., additional, Schmitt, J. H. M. M., additional, Schöfer, P., additional, Solano, E., additional, Sota, A., additional, Stahl, O., additional, Stock, S., additional, Stuber, T., additional, Stürmer, J., additional, Suárez, J. C., additional, Tabernero, H. M., additional, Tulloch, S. M., additional, Veredas, G., additional, Vico-Linares, J. I., additional, Vilardell, F., additional, Wagner, K., additional, Winkler, J., additional, Wolthoff, V., additional, Yan, F., additional, and Osorio, M. R. Zapatero, additional
Published: 2019
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213. Stellar activity analysis of Barnard’s Star: Very slow rotation and evidence for long-term activity cycle

Author: Toledo-Padrón, B, primary, Hernández, J I González, additional, Rodríguez-López, C, additional, Mascareño, A Suárez, additional, Rebolo, R, additional, Butler, R P, additional, Ribas, I, additional, Anglada-Escudé, G, additional, Johnson, E N, additional, Reiners, A, additional, Caballero, J A, additional, Quirrenbach, A, additional, Amado, P J, additional, Béjar, V J S, additional, Morales, J C, additional, Perger, M, additional, Jeffers, S V, additional, Vogt, S, additional, Teske, J, additional, Shectman, S, additional, Crane, J, additional, Díaz, M, additional, Arriagada, P, additional, Holden, B, additional, Burt, J, additional, Rodríguez, E, additional, Herrero, E, additional, Murgas, F, additional, Pallé, E, additional, Morales, N, additional, López-González, M J, additional, Alonso, E Díez, additional, Tuomi, M, additional, Kiraga, M, additional, Engle, S G, additional, Guinan, E F, additional, Strachan, J B P, additional, Aceituno, F J, additional, Aceituno, J, additional, Casanova, V M, additional, Martín-Ruiz, S, additional, Montes, D, additional, Ortiz, J L, additional, Sota, A, additional, Briol, J, additional, Barbieri, L, additional, Cervini, I, additional, Deldem, M, additional, Dubois, F, additional, Hambsch, F-J, additional, Harris, B, additional, Kotnik, C, additional, Logie, L, additional, Lopez, J, additional, McNeely, M, additional, Ogmen, Y, additional, Pérez, L, additional, Rau, S, additional, Rodríguez, D, additional, Urquijo, F S, additional, and Vanaverbeke, S, additional
Published: 2019
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214. A transiting super-Earth close to the inner edge of the habitable zone of an M0 dwarf star

Author: Alonso, E Díez, primary, Hernández, J I González, additional, Toledo–Padrón, B, additional, Gómez, S L Suárez, additional, Mascareño, A Suárez, additional, Aguado, D S, additional, Gutiérrez, C González, additional, Cabrera-Lavers, A, additional, Carballido–Landeira, J, additional, Bonavera, L, additional, Juez, F J de Cos, additional, and Rebolo, R, additional
Published: 2018
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215. Chemical Abundances of Neutron-capture Elements in Exoplanet-hosting Stars

Author: Mena, E. Delgado, primary, Adibekyan, V. Zh., additional, Figueira, P., additional, Hernández, J. I. González, additional, Santos, N. C., additional, Tsantaki, M., additional, Sousa, S. G., additional, Faria, J. P., additional, Suárez-Andrés, L., additional, and Israelian, G., additional
Published: 2018
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216. 3D non-LTE corrections for Li abundance and 6Li/7Li isotopic ratio in solar-type stars I. Application to HD 207129 and HD 95456

Author: Harutyunyan, G., Steffen, M., Mott, A., Caffau, E., Israelian, G., Hernández, J. I. González, Strassmeier, K. G., Harutyunyan, G., Steffen, M., Mott, A., Caffau, E., Israelian, G., Hernández, J. I. González, and Strassmeier, K. G.
Abstract: Convective motions in solar-type stellar atmospheres induce Doppler shifts that affect the strengths and shapes of spectral absorption lines and create slightly asymmetric line profiles. 1D LTE studies of elemental abundances are not able to reproduce this phenomenon, which becomes particularly important when modeling the impact of isotopic fine structure, like the subtle depression created by the 6Li isotope on the red wing of the Li I resonance doublet line. The purpose of this work is to provide corrections for the lithium abundance, A(Li), and the 6Li/7Li ratio that can easily be applied to correct 1D LTE lithium abundances in G and F dwarf stars of approximately solar mass and metallicity for 3D and non-LTE (NLTE) effects. The corrections for A(Li) and 6Li/7Li are computed using grids of 3D NLTE and 1D LTE synthetic lithium line profiles, generated from 3D hydro-dynamical CO5BOLD and 1D hydrostatic model atmospheres, respectively. The 3D NLTE corrections are then approximated by analytical expressions as a function of the stellar parameters. These are applied to adjust the 1D LTE isotopic lithium abundances in two solar-type stars, HD 207129 and HD 95456. The derived 3D NLTE corrections range between -0.01 and +0.11 dex for A(Li), and between -4.9 and -0.4% for the 6Li/7Li ratio, depending on the adopted stellar parameters. In the case of the 6Li/7Li ratio, our corrections are always negative, showing that 1D LTE analysis can significantly overestimate (up to 4.9 percentage points) the presence of 6Li in the atmospheres of solar-like dwarf stars. These results emphasize the importance of reliable 3D model atmospheres combined with NLTE line formation for deriving precise isotopic lithium abundances. Although 3D NLTE spectral synthesis implies an extensive computational effort, the results can be made accessible with parametric tools like the ones presented in this work., Comment: 22 pages, 14 figures, 9 tables, accepted for publication in A&A
Published: 2018
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217. Chemical abundances of neutron capture elements in exoplanet-hosting stars

Author: Mena, E. Delgado, Adibekyan, V. Zh., Figueira, P., Hernández, J. I. González, Santos, N. C., Tsantaki, M., Sousa, S. G., Faria, J. P., Suárez-Andrés, L., Israelian, G., Mena, E. Delgado, Adibekyan, V. Zh., Figueira, P., Hernández, J. I. González, Santos, N. C., Tsantaki, M., Sousa, S. G., Faria, J. P., Suárez-Andrés, L., and Israelian, G.
Abstract: To understand the formation and composition of planetary systems it is important to study their host stars composition since both are formed in the same stellar nebula. In this work we analyze the behaviour of chemical abundances of Cu, Zn, Sr, Y, Zr, Ba, Ce, Nd and Eu in the large and homogeneous HARPS-GTO planet search sample ($R \sim$ 115000). This sample is composed of 120 stars hosting high-mass planets, 29 stars hosting exclusively Neptunians and Super-Earths and 910 stars without detected giant planets. We compare the [X/Fe] ratios of such elements in different metallicity bins and we find that planet hosts present higher abundances of Zn for [Fe/H]$<$--0.1 dex. On the other hand, Ba, Sr, Ce and Zr abundances are underabundant in stars with planets, with a bigger difference for stars only hosting low-mass planets. However, most of the offsets found can be explained by differences in stellar parameters and by the fact that planet hosts at low metallicity mostly belong to the Galactic thick disk. Only in the case of Ba we find a statistically significant (3$\sigma$) underabundance of 0.03 dex for low-mass planet hosts. The origin of these elements is quite complex due to their evolution during the history of the Galaxy. Therefore, it is necessary to understand and characterize the stellar populations to which planet hosts belong in order to do a fair comparison with stars without detected planets. This work demonstrates that the effects of Galactic chemical evolution and not the presence of planets mostly account for the differences we find., Comment: Accepted for publication in PASP
Published: 2018
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218. The HADES RV Programme with HARPS-N@TNG VIII. Gl15A: A multiple wide planetary system sculpted by binary interaction

Author: Pinamonti, M., Damasso, M., Marzari, F., Sozzetti, A., Desidera, S., Maldonado, J., Scandariato, G., Affer, L., Lanza, A. F., Bignamini, A., Bonomo, A. S., Borsa, F., Claudi, R., Cosentino, R., Giacobbe, P., González-Álvarez, E., Hernández, J. I. González, Gratton, R., Leto, G., Malavolta, L., Fiorenzano, A. Martinez, Micela, G., Molinari, E., Pagano, I., Pedani, M., Perger, M., Piotto, G., Rebolo, R., Ribas, I., Mascareño, A. Suárez, Toledo-Padrón, B., Pinamonti, M., Damasso, M., Marzari, F., Sozzetti, A., Desidera, S., Maldonado, J., Scandariato, G., Affer, L., Lanza, A. F., Bignamini, A., Bonomo, A. S., Borsa, F., Claudi, R., Cosentino, R., Giacobbe, P., González-Álvarez, E., Hernández, J. I. González, Gratton, R., Leto, G., Malavolta, L., Fiorenzano, A. Martinez, Micela, G., Molinari, E., Pagano, I., Pedani, M., Perger, M., Piotto, G., Rebolo, R., Ribas, I., Mascareño, A. Suárez, and Toledo-Padrón, B.
Abstract: We present 20 years of radial velocity (RV) measurements of the M1 dwarf Gl15A, combining 5 years of intensive RV monitoring with the HARPS-N spectrograph with 15 years of archival HIRES/Keck RV data. We carry out an MCMC-based analysis of the RV time series, inclusive of Gaussian Process (GP) approach to the description of stellar activity induced RV variations. Our analysis confirms the Keplerian nature and refines the orbital solution for the 11.44-day period super Earth, Gl15A\,b, reducing its amplitude to $1.68^{+0.17}_{-0.18}$ m s$^{-1}$ ($M \sin i = 3.03^{+0.46}_{-0.44}$ M$_\oplus$), and successfully models a long-term trend in the combined RV dataset in terms of a Keplerian orbit with a period around 7600 days and an amplitude of $2.5^{+1.3}_{-1.0}$ m s$^{-1}$, corresponding to a super-Neptune mass ($M \sin i = 36^{+25}_{-18}$ M$_\oplus$) planetary companion. We also discuss the present orbital configuration of Gl15A planetary system in terms of the possible outcomes of Lidov-Kozai interactions with the wide-separation companion Gl15B in a suite of detailed numerical simulations. In order to improve the results of the dynamical analysis, we derive a new orbital solution for the binary system, combining our RV measurements with astrometric data from the WDS catalogue. The eccentric Lidov-Kozai analysis shows the strong influence of Gl15B on the Gl15A planetary system, which can produce orbits compatible with the observed configuration for initial inclinations of the planetary system between $75^\circ$ and $90^\circ$, and can also enhance the eccentricity of the outer planet well above the observed value, even resulting in orbital instability, for inclinations around $0^\circ$ and $15^\circ - 30^\circ$. The Gl15A system is the multi-planet system closest to Earth, at $3.57$ pc, and hosts the longest period RV sub-jovian mass planet discovered so far., Comment: 19 pages, 14 figures, accepted for publication in A\&A
Published: 2018
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219. Calibrating the metallicity of M dwarfs in wide physical binaries with F-, G-, and K- primaries - I: High-resolution spectroscopy with HERMES: stellar parameters, abundances, and kinematics

Author: Montes, D., González-Peinado, R., Tabernero, H. M., Caballero, J. A., Marfil, E., Alonso-Floriano, F. J., Cortés-Contreras, M., Hernández, J. I. González, Klutsch, A., Moreno-Jódar, C., Montes, D., González-Peinado, R., Tabernero, H. M., Caballero, J. A., Marfil, E., Alonso-Floriano, F. J., Cortés-Contreras, M., Hernández, J. I. González, Klutsch, A., and Moreno-Jódar, C.
Abstract: We investigated almost 500 stars distributed among 193 binary or multiple systems made of late-F, G-, or early-K primaries and late-K or M dwarf companion candidates. For all of them, we compiled or measured coordinates, J-band magnitudes, spectral types, distances, and proper motions.With these data, we established a sample of 192 physically bound systems. In parallel, we carried out observations with HERMES/Mercator and obtained high resolution spectra for the 192 primaries and five secondaries. We used these spectra and the automatic StePar code for deriving precise stellar atmospheric parameters: Teff, log g, Vmicro, and chemical abundances for 13 atomic species, including [Fe/H]. After computing Galactocentric space velocities for all the primary stars, we performed a kinematic analysis and classified them in different Galactic populations and stellar kinematic groups of very different ages, which match our own metallicity determinations and isochronal age estimations. In particular, we identified three systems in the halo and 33 systems in the young Local Association, Ursa Major and Castor moving groups, and IC 2391 and Hyades Superclusters. We finally studied the exoplanet-metallicity relation in our 193 primaries and made a list 13 M-dwarf companions with very high metallicity that can be the targets of new dedicated exoplanet surveys. All in all, our dataset will be of great help for future works on the accurate determination of metallicity of M dwarfs., Comment: accepted for publication in MNRAS, 49 pages, 11 figures and 10 tables
Published: 2018
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220. The First Post-Kepler Brightness Dips of KIC 8462852

Author: Boyajian, Tabetha S., Alonso, Roi, Ammerman, Alex, Armstrong, David, Ramos, A. Asensio, Barkaoui, K., Beatty, Thomas G., Benkhaldoun, Z., Benni, Paul, Bentley, Rory, Berdyugin, Andrei, Berdyugina, Svetlana, Bergeron, Serge, Bieryla, Allyson, Blain, Michaela G., Blanco, Alicia Capetillo, Bodman, Eva H. L., Boucher, Anne, Bradley, Mark, Brincat, Stephen M., Brink, Thomas G., Briol, John, Brown, David J. A., Budaj, J., Burdanov, A., Cale, B., Carbo, Miguel Aznar, Garcia, R. Castillo, Clark, Wendy J, Clayton, Geoffrey C., Clem, James L., Coker, Phillip H, Cook, Evan M., Copperwheat, Chris M., Curtis, J., Cutri, R. M., Cseh, B., Cynamon, C. H., Daniels, Alex J., Davenport, James R. A., Deeg, Hans J., De Lorenzo, Roberto, De Jaeger, Thomas, Desrosiers, Jean-Bruno, Dolan, John, Dowhos, D. J., Dubois, Franky, Durkee, R., Dvorak, Shawn, Easley, Lynn, Edwards, N., Ellis, Tyler G., Erdelyi, Emery, Ertel, Steve, Farfán, Rafael. G., Farihi, J., Filippenko, Alexei V., Foxell, Emma, Gandolfi, Davide, Garcia, Faustino, Giddens, F., Gillon, M., González-Carballo, Juan-Luis, González-Fernández, C., Hernández, J. I. González, Graham, Keith A., Greene, Kenton A., Gregorio, J., Hallakoun, Na'ama, Hanyecz, Ottó, Harp, G. R., Henry, Gregory W., Herrero, E., Hildbold, Caleb F., Hinzel, D., Holgado, G., Ignácz, Bernadett, Ivanov, Valentin D., Jehin, E., Jermak, Helen E., Johnston, Steve, Kafka, S., Kalup, Csilla, Kardasis, Emmanuel, Kaspi, Shai, Kennedy, Grant M., Kiefer, F., Kielty, C. L., Kessler, Dennis, Kiiskinen, H., Killestein, T. L., King, Ronald A., Kollar, V., Korhonen, H., Kotnik, C., Könyves-Tóth, Réka, Kriskovics, Levente, Krumm, Nathan, Krushinsky, Vadim, Kundra, E., Lachapelle, Francois-Rene, Lacourse, D., Lake, P., Lam, Kristine, Lamb, Gavin P., Lane, Dave, Lau, Marie Wingyee, Lewin, Pablo, Lintott, Chris, Lisse, Carey, Logie, Ludwig, Longeard, Nicolas, Villanueva, M. Lopez, Ludington, E. Whit, Mainzer, A., Malo, Lison, Maloney, Chris, Mann, A., Mantero, A., Marengo, Massimo, Marchant, Jon, González, M. J. Martinez, Masiero, Joseph R., Mauerhan, Jon C., Mccormac, James, Mcneely, Aaron, Meng, Huan Y. A., Miller, Mike, Molnar, Lawrence A., Morales, J. C., Morris, Brett M., Muterspaugh, Matthew W., Nespral, David, Nugent, C. R., Nugent, Katherine M., Odasso, A., O'keeffe, Derek, Oksanen, A., O'meara, John M., Ordasi, András, Osborn, Hugh, Ott, John J., Parks, J. R., Perez, Diego Rodriguez, Petriew, Vance, Pickard, R., Pál, András, Plavchan, P., Plaza, C. Westendorp, Pollacco, Don, Nuñez, F. Pozo, Pozuelos, F. J., Rau, Steve, Redfield, Seth, Relles, Howard, Ribas, I., Richards, Jon, Saario, Joonas L. O., Safron, Emily J., Sallai, J. Martin, Sárneczky, Krisztián, Schaefer, Bradley E., Schumer, Clea F., Schwartzendruber, Madison, Siegel, Michael H., Siemion, Andrew P. V., Simmons, Brooke D., Simon, Joshua D., Simón-Diaz, S., Sitko, Michael L., Socas-Navarro, Hector, Sódor, Á., Starkey, Donn, Steele, Iain A., Stone, Geoff, Street, R. A., Sullivan, Tricia, Suomela, J., Swift, J. J., Szabó, Gyula M., Szabó, Róbert, Szakáts, Róbert, Szalai, Tamás, Tanner, Angelle M., Toledo-Padrón, B., Tordai, Tamás, Triaud, Amaury H. M. J., Turner, Jake D., Ulowetz, Joseph H., Urbanik, Marian, Vanaverbeke, Siegfried, Vanderburg, Andrew, Vida, Krisztián, Vietje, Brad P., Vinkó, József, Von Braun, K., Waagen, Elizabeth O., Walsh, Dan, Watson, Christopher A., Weir, R. C., Wenzel, Klaus, Williamson, Michael W., Wright, Jason T., Wyatt, M. C., Zheng, Weikang, Zsidi, Gabriella, Boyajian, Tabetha S., Alonso, Roi, Ammerman, Alex, Armstrong, David, Ramos, A. Asensio, Barkaoui, K., Beatty, Thomas G., Benkhaldoun, Z., Benni, Paul, Bentley, Rory, Berdyugin, Andrei, Berdyugina, Svetlana, Bergeron, Serge, Bieryla, Allyson, Blain, Michaela G., Blanco, Alicia Capetillo, Bodman, Eva H. L., Boucher, Anne, Bradley, Mark, Brincat, Stephen M., Brink, Thomas G., Briol, John, Brown, David J. A., Budaj, J., Burdanov, A., Cale, B., Carbo, Miguel Aznar, Garcia, R. Castillo, Clark, Wendy J, Clayton, Geoffrey C., Clem, James L., Coker, Phillip H, Cook, Evan M., Copperwheat, Chris M., Curtis, J., Cutri, R. M., Cseh, B., Cynamon, C. H., Daniels, Alex J., Davenport, James R. A., Deeg, Hans J., De Lorenzo, Roberto, De Jaeger, Thomas, Desrosiers, Jean-Bruno, Dolan, John, Dowhos, D. J., Dubois, Franky, Durkee, R., Dvorak, Shawn, Easley, Lynn, Edwards, N., Ellis, Tyler G., Erdelyi, Emery, Ertel, Steve, Farfán, Rafael. G., Farihi, J., Filippenko, Alexei V., Foxell, Emma, Gandolfi, Davide, Garcia, Faustino, Giddens, F., Gillon, M., González-Carballo, Juan-Luis, González-Fernández, C., Hernández, J. I. González, Graham, Keith A., Greene, Kenton A., Gregorio, J., Hallakoun, Na'ama, Hanyecz, Ottó, Harp, G. R., Henry, Gregory W., Herrero, E., Hildbold, Caleb F., Hinzel, D., Holgado, G., Ignácz, Bernadett, Ivanov, Valentin D., Jehin, E., Jermak, Helen E., Johnston, Steve, Kafka, S., Kalup, Csilla, Kardasis, Emmanuel, Kaspi, Shai, Kennedy, Grant M., Kiefer, F., Kielty, C. L., Kessler, Dennis, Kiiskinen, H., Killestein, T. L., King, Ronald A., Kollar, V., Korhonen, H., Kotnik, C., Könyves-Tóth, Réka, Kriskovics, Levente, Krumm, Nathan, Krushinsky, Vadim, Kundra, E., Lachapelle, Francois-Rene, Lacourse, D., Lake, P., Lam, Kristine, Lamb, Gavin P., Lane, Dave, Lau, Marie Wingyee, Lewin, Pablo, Lintott, Chris, Lisse, Carey, Logie, Ludwig, Longeard, Nicolas, Villanueva, M. Lopez, Ludington, E. Whit, Mainzer, A., Malo, Lison, Maloney, Chris, Mann, A., Mantero, A., Marengo, Massimo, Marchant, Jon, González, M. J. Martinez, Masiero, Joseph R., Mauerhan, Jon C., Mccormac, James, Mcneely, Aaron, Meng, Huan Y. A., Miller, Mike, Molnar, Lawrence A., Morales, J. C., Morris, Brett M., Muterspaugh, Matthew W., Nespral, David, Nugent, C. R., Nugent, Katherine M., Odasso, A., O'keeffe, Derek, Oksanen, A., O'meara, John M., Ordasi, András, Osborn, Hugh, Ott, John J., Parks, J. R., Perez, Diego Rodriguez, Petriew, Vance, Pickard, R., Pál, András, Plavchan, P., Plaza, C. Westendorp, Pollacco, Don, Nuñez, F. Pozo, Pozuelos, F. J., Rau, Steve, Redfield, Seth, Relles, Howard, Ribas, I., Richards, Jon, Saario, Joonas L. O., Safron, Emily J., Sallai, J. Martin, Sárneczky, Krisztián, Schaefer, Bradley E., Schumer, Clea F., Schwartzendruber, Madison, Siegel, Michael H., Siemion, Andrew P. V., Simmons, Brooke D., Simon, Joshua D., Simón-Diaz, S., Sitko, Michael L., Socas-Navarro, Hector, Sódor, Á., Starkey, Donn, Steele, Iain A., Stone, Geoff, Street, R. A., Sullivan, Tricia, Suomela, J., Swift, J. J., Szabó, Gyula M., Szabó, Róbert, Szakáts, Róbert, Szalai, Tamás, Tanner, Angelle M., Toledo-Padrón, B., Tordai, Tamás, Triaud, Amaury H. M. J., Turner, Jake D., Ulowetz, Joseph H., Urbanik, Marian, Vanaverbeke, Siegfried, Vanderburg, Andrew, Vida, Krisztián, Vietje, Brad P., Vinkó, József, Von Braun, K., Waagen, Elizabeth O., Walsh, Dan, Watson, Christopher A., Weir, R. C., Wenzel, Klaus, Williamson, Michael W., Wright, Jason T., Wyatt, M. C., Zheng, Weikang, and Zsidi, Gabriella
Abstract: We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in October 2015, and a sequence of dipping began in 2017 May continuing on through the end of 2017, when the star was no longer visible from Earth. We distinguish four main 1-2.5% dips, named "Elsie," "Celeste," "Skara Brae," and "Angkor", which persist on timescales from several days to weeks. Our main results so far are: (i) there are no apparent changes of the stellar spectrum or polarization during the dips; (ii) the multiband photometry of the dips shows differential reddening favoring non-grey extinction. Therefore, our data are inconsistent with dip models that invoke optically thick material, but rather they are in-line with predictions for an occulter consisting primarily of ordinary dust, where much of the material must be optically thin with a size scale <<1um, and may also be consistent with models invoking variations intrinsic to the stellar photosphere. Notably, our data do not place constraints on the color of the longer-term "secular" dimming, which may be caused by independent processes, or probe different regimes of a single process., Comment: 19 pages, 8 figures, accepted for publication in ApJL
Published: 2018
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221. C/O vs Mg/Si ratios in solar type stars: The HARPS sample

Author: Suárez-Andrés, L., Israelian, G., Hernández, J. I. González, Adibekyan, V. Zh., Mena, E. Delgado, Santos, N. C., Sousa, S. G., Suárez-Andrés, L., Israelian, G., Hernández, J. I. González, Adibekyan, V. Zh., Mena, E. Delgado, Santos, N. C., and Sousa, S. G.
Abstract: Aims. We present a detailed study of the Mg/Si and C/O ratios and their importance in determining the mineralogy of planetary companions. Methods. Using 499 solar-like stars from the HARPS sample, we determine C/O and Mg/Si elemental abundance ratios to study the nature of the possible planets formed. We separated the planetary population in low-mass planets ( < 30 $\rm M_{\odot}$) and high-mass planets ( > 30 $\rm M_{\odot}$) to test for possible relation with the mass. Results. We find a diversity of mineralogical ratios that reveal the different kinds of planetary systems that can be formed, most of them dissimilar to our solar system. The different values of the Mg/Si and C/O ratios can determine different composition of planets formed. We found that 100\% of our planetary sample present C/O < 0.8. 86\% of stars with high-mass companions present 0.8 > C/O > 0.4, while 14\% present C/O values lower than 0.4. Regarding Mg/Si, all stars with low-mass planetary companion showed values between 1 and 2, while 85% of the high-mass companion sample does. The other 15\% showed Mg/Si values below 1. No stars with planets were found with Mg/Si > 2. Planet hosts with low-mass companions present C/O and Mg/Si ratios similar to those found in the Sun, whereas stars with high-mass companions have lower C/O., Comment: 9 pages, 12 figues. Accepted in A&A
Published: 2018
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222. The discovery of WASP-134b, WASP-134c, WASP-137b, WASP-143b and WASP-146b: three hot Jupiters and a pair of warm Jupiters orbiting Solar-type stars

Author: Anderson, D. R., Bouchy, F., Brown, D. J. A., Cameron, A. Collier, Delrez, L., Gillon, M., Hernández, J. I. González, Hellier, C., Jehin, E., Lendl, M., Maxted, P. F. L., Neveu-VanMalle, M., Nielsen, L. D., Pepe, F., Perger, M., Pollacco, D., Queloz, D., Rey, J., Ségransan, D., Smalley, B., Toledo-Padrón, B., Triaud, A. H. M. J., Turner, O. D., Udry, S., West, R. G., Anderson, D. R., Bouchy, F., Brown, D. J. A., Cameron, A. Collier, Delrez, L., Gillon, M., Hernández, J. I. González, Hellier, C., Jehin, E., Lendl, M., Maxted, P. F. L., Neveu-VanMalle, M., Nielsen, L. D., Pepe, F., Perger, M., Pollacco, D., Queloz, D., Rey, J., Ségransan, D., Smalley, B., Toledo-Padrón, B., Triaud, A. H. M. J., Turner, O. D., Udry, S., and West, R. G.
Abstract: We report the discovery by WASP of five planets orbiting moderately bright ($V$ = 11.0-12.9) Solar-type stars. WASP-137b, WASP-143b and WASP-146b are typical hot Jupiters in orbits of 3-4 d and with masses in the range 0.68--1.11 $M_{\rm Jup}$. WASP-134 is a metal-rich ([Fe/H] = +0.40 $\pm$ 0.07]) G4 star orbited by two warm Jupiters: WASP-134b ($M_{\rm pl}$ = 1.41 $M_{\rm Jup}$; $P = 10.1$ d; $e = 0.15 \pm 0.01$; $T_{\rm eql}$ = 950 K) and WASP-134c ($M_{\rm pl} \sin i$ = 0.70 $M_{\rm Jup}$; $P = 70.0$ d; $e = 0.17 \pm 0.09$; $T_{\rm eql}$ = 500 K). From observations of the Rossiter-McLaughlin effect of WASP-134b, we find its orbit to be misaligned with the spin of its star ($\lambda = -44 \pm 10^\circ$). WASP-134 is a rare example of a system with a short-period giant planet and a nearby giant companion. In-situ formation or disc migration seem more likely explanations for such systems than does high-eccentricity migration., Comment: Submitted to AJ. 10 pages, 8 figures, 4 tables
Published: 2018

223. Stellar activity analysis of Barnard's Star: Very slow rotation and evidence for long-term activity cycle

Author: Toledo-Padrón, B., Hernández, J. I. González, Rodríguez-López, C., Mascareño, A. Suárez, Rebolo, R., Butler, R. P., Ribas, I., Anglada-Escudé, G., Johnson, E. N., Reiners, A., Caballero, J. A., Quirrenbach, A., Amado, P. J., Béjar, V. J. S., Morales, J. C., Perger, M., Jeffers, S. V., Vogt, S., Teske, J., Shectman, S., Crane, J., Díaz, M., Arriagada, P., Holden, B., Burt, J., Rodríguez, E., Herrero, E., Murgas, F., Pallé, E., Morales, N., López-González, M. J., Alonso, E. Díez, Tuomi, M., Kiraga, M., Engle, S. G., Guinan, E. F., Strachan, J. B. P., Aceituno, F. J., Aceituno, J., Casanova, V. M., Martín-Ruiz, S., Montes, D., Ortiz, J. L., Sota, A., Briol, J., Barbieri, L., Cervini, I., Deldem, M., Dubois, F., Hambsch, F. -J., Harris, B., Kotnik, C., Logie, L., Lopez, J., McNeely, M., Ogmen, Y., Pérez, L., Rau, S., Rodríguez, D., Urquijo, F. S., Vanaverbeke, S., Toledo-Padrón, B., Hernández, J. I. González, Rodríguez-López, C., Mascareño, A. Suárez, Rebolo, R., Butler, R. P., Ribas, I., Anglada-Escudé, G., Johnson, E. N., Reiners, A., Caballero, J. A., Quirrenbach, A., Amado, P. J., Béjar, V. J. S., Morales, J. C., Perger, M., Jeffers, S. V., Vogt, S., Teske, J., Shectman, S., Crane, J., Díaz, M., Arriagada, P., Holden, B., Burt, J., Rodríguez, E., Herrero, E., Murgas, F., Pallé, E., Morales, N., López-González, M. J., Alonso, E. Díez, Tuomi, M., Kiraga, M., Engle, S. G., Guinan, E. F., Strachan, J. B. P., Aceituno, F. J., Aceituno, J., Casanova, V. M., Martín-Ruiz, S., Montes, D., Ortiz, J. L., Sota, A., Briol, J., Barbieri, L., Cervini, I., Deldem, M., Dubois, F., Hambsch, F. -J., Harris, B., Kotnik, C., Logie, L., Lopez, J., McNeely, M., Ogmen, Y., Pérez, L., Rau, S., Rodríguez, D., Urquijo, F. S., and Vanaverbeke, S.
Abstract: The search for Earth-like planets around late-type stars using ultra-stable spectrographs requires a very precise characterization of the stellar activity and the magnetic cycle of the star, since these phenomena induce radial velocity (RV) signals that can be misinterpreted as planetary signals. Among the nearby stars, we have selected Barnard's Star (Gl 699) to carry out a characterization of these phenomena using a set of spectroscopic data that covers about 14.5 years and comes from seven different spectrographs: HARPS, HARPS-N, CARMENES, HIRES, UVES, APF, and PFS; and a set of photometric data that covers about 15.1 years and comes from four different photometric sources: ASAS, FCAPT-RCT, AAVSO, and SNO. We have measured different chromospheric activity indicators (H$\alpha$, Ca~{\sc II}~HK and Na I D), as well as the FWHM of the cross-correlation function computed for a sub-set of the spectroscopic data. The analysis of Generalized Lomb-Scargle periodograms of the time series of different activity indicators reveals that the rotation period of the star is 145 $\pm$ 15 days, consistent with the expected rotation period according to the low activity level of the star and previous claims. The upper limit of the predicted activity-induced RV signal corresponding to this rotation period is about 1 m/s. We also find evidence of a long-term cycle of 10 $\pm$ 2 years that is consistent with previous estimates of magnetic cycles from photometric time series in other M stars of similar activity levels. The available photometric data of the star also support the detection of both the long-term and the rotation signals., Comment: 16 pages, 20 figures
Published: 2018
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224. A candidate super-Earth planet orbiting near the snow line of Barnard's star

Author: Ribas, I., Tuomi, M., Reiners, A., Butler, R. P., Morales, J. C., Perger, M., Dreizler, S., Rodríguez-López, C., Hernández, J. I. González, Rosich, A., Feng, F., Trifonov, T., Vogt, S. S., Caballero, J. A., Hatzes, A., Herrero, E., Jeffers, S. V., Lafarga, M., Murgas, F., Nelson, R. P., Rodríguez, E., Strachan, J. B. P., Tal-Or, L., Teske, J., Toledo-Padrón, B., Zechmeister, M., Quirrenbach, A., Amado, P. J., Azzaro, M., Béjar, V. J. S., Barnes, J. R., Berdiñas, Z. M., Burt, J., Coleman, G., Cortés-Contreras, M., Crane, J., Engle, S. G., Guinan, E. F., Haswell, C. A., Henning, Th., Holden, B., Jenkins, J., Jones, H. R. A., Kaminski, A., Kiraga, M., Kürster, M., Lee, M. H., López-González, M. J., Montes, D., Morin, J., Ofir, A., Pallé, E., Rebolo, R., Reffert, S., Schweitzer, A., Seifert, W., Shectman, S. A., Staab, D., Street, R. A., Mascareño, A. Suárez, Tsapras, Y., Wang, S. X., Anglada-Escudé, G., Ribas, I., Tuomi, M., Reiners, A., Butler, R. P., Morales, J. C., Perger, M., Dreizler, S., Rodríguez-López, C., Hernández, J. I. González, Rosich, A., Feng, F., Trifonov, T., Vogt, S. S., Caballero, J. A., Hatzes, A., Herrero, E., Jeffers, S. V., Lafarga, M., Murgas, F., Nelson, R. P., Rodríguez, E., Strachan, J. B. P., Tal-Or, L., Teske, J., Toledo-Padrón, B., Zechmeister, M., Quirrenbach, A., Amado, P. J., Azzaro, M., Béjar, V. J. S., Barnes, J. R., Berdiñas, Z. M., Burt, J., Coleman, G., Cortés-Contreras, M., Crane, J., Engle, S. G., Guinan, E. F., Haswell, C. A., Henning, Th., Holden, B., Jenkins, J., Jones, H. R. A., Kaminski, A., Kiraga, M., Kürster, M., Lee, M. H., López-González, M. J., Montes, D., Morin, J., Ofir, A., Pallé, E., Rebolo, R., Reffert, S., Schweitzer, A., Seifert, W., Shectman, S. A., Staab, D., Street, R. A., Mascareño, A. Suárez, Tsapras, Y., Wang, S. X., and Anglada-Escudé, G.
Abstract: At a distance of 1.8 parsecs, Barnard's star (Gl 699) is a red dwarf with the largest apparent motion of any known stellar object. It is the closest single star to the Sun, second only to the alpha Centauri triple stellar system. Barnard's star is also among the least magnetically active red dwarfs known and has an estimated age older than our Solar System. Its properties have made it a prime target for planet searches employing techniques such as radial velocity, astrometry, and direct imaging, all with different sensitivity limits but ultimately leading to disproved or null results. Here we report that the combination of numerous measurements from high-precision radial velocity instruments reveals the presence of a low-amplitude but significant periodic signal at 233 days. Independent photometric and spectroscopic monitoring, as well as the analysis of instrumental systematic effects, show that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth with a minimum mass of 3.2 Earth masses orbiting near its snow-line. The combination of all radial velocity datasets spanning 20 years additionally reveals a long-term modulation that could arise from a magnetic activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the proposed planet has a maximum angular separation of 220 milli-arcseconds from Barnard's star, making it an excellent target for complementary direct imaging and astrometric observations., Comment: 38 pages, 7 figures, 4 tables, author's version of published paper in Nature journal
Published: 2018
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225. The First Post- Kepler Brightness Dips of KIC 8462852

Author: Boyajian, Tabetha. S., primary, Alonso, Roi, additional, Ammerman, Alex, additional, Armstrong, David, additional, Ramos, A. Asensio, additional, Barkaoui, K., additional, Beatty, Thomas G., additional, Benkhaldoun, Z., additional, Benni, Paul, additional, O. Bentley, Rory, additional, Berdyugin, Andrei, additional, Berdyugina, Svetlana, additional, Bergeron, Serge, additional, Bieryla, Allyson, additional, Blain, Michaela G., additional, Blanco, Alicia Capetillo, additional, Bodman, Eva H. L., additional, Boucher, Anne, additional, Bradley, Mark, additional, Brincat, Stephen M., additional, Brink, Thomas G., additional, Briol, John, additional, Brown, David J. A., additional, Budaj, J., additional, Burdanov, A., additional, Cale, B., additional, Carbo, Miguel Aznar, additional, García, R. Castillo, additional, Clark, Wendy J, additional, Clayton, Geoffrey C., additional, Clem, James L., additional, Coker, Phillip H, additional, Cook, Evan M., additional, Copperwheat, Chris M., additional, Curtis, J. L., additional, Cutri, R. M., additional, Cseh, B., additional, Cynamon, C. H., additional, Daniels, Alex J., additional, Davenport, James R. A., additional, Deeg, Hans J., additional, Lorenzo, Roberto De, additional, Jaeger, Thomas de, additional, Desrosiers, Jean-Bruno, additional, Dolan, John, additional, Dowhos, D. J., additional, Dubois, Franky, additional, Durkee, R., additional, Dvorak, Shawn, additional, Easley, Lynn, additional, Edwards, N., additional, Ellis, Tyler G., additional, Erdelyi, Emery, additional, Ertel, Steve, additional, Farfán, Rafael. G., additional, Farihi, J., additional, Filippenko, Alexei V., additional, Foxell, Emma, additional, Gandolfi, Davide, additional, Garcia, Faustino, additional, Giddens, F., additional, Gillon, M., additional, González-Carballo, Juan-Luis, additional, González-Fernández, C., additional, Hernández, J. I. González, additional, Graham, Keith A., additional, Greene, Kenton A., additional, Gregorio, J., additional, Hallakoun, Na’ama, additional, Hanyecz, Ottó, additional, Harp, G. R., additional, Henry, Gregory W., additional, Herrero, E., additional, Hildbold, Caleb F., additional, Hinzel, D., additional, Holgado, G., additional, Ignácz, Bernadett, additional, Ilyin, Ilya, additional, Ivanov, Valentin D., additional, Jehin, E., additional, Jermak, Helen E., additional, Johnston, Steve, additional, Kafka, S., additional, Kalup, Csilla, additional, Kardasis, Emmanuel, additional, Kaspi, Shai, additional, Kennedy, Grant M., additional, Kiefer, F., additional, Kielty, C. L., additional, Kessler, Dennis, additional, Kiiskinen, H., additional, Killestein, T. L., additional, King, Ronald A., additional, Kollar, V., additional, Korhonen, H., additional, Kotnik, C., additional, Könyves-Tóth, Réka, additional, Kriskovics, Levente, additional, Krumm, Nathan, additional, Krushinsky, Vadim, additional, Kundra, E., additional, Lachapelle, Francois-Rene, additional, LaCourse, D., additional, Lake, P., additional, Lam, Kristine, additional, Lamb, Gavin P., additional, Lane, Dave, additional, Lau, Marie Wingyee, additional, Lewin, Pablo, additional, Lintott, Chris, additional, Lisse, Carey, additional, Logie, Ludwig, additional, Longeard, Nicolas, additional, Villanueva, M. Lopez, additional, Ludington, E. Whit, additional, Mainzer, A., additional, Malo, Lison, additional, Maloney, Chris, additional, Mann, A., additional, Mantero, A., additional, Marengo, Massimo, additional, Marchant, Jon, additional, Martínez González, M. J., additional, Masiero, Joseph R., additional, Mauerhan, Jon C., additional, McCormac, James, additional, McNeely, Aaron, additional, Meng, Huan Y. A., additional, Miller, Mike, additional, Molnar, Lawrence A., additional, Morales, J. C., additional, Morris, Brett M., additional, Muterspaugh, Matthew W., additional, Nespral, David, additional, Nugent, C. R., additional, Nugent, Katherine M., additional, Odasso, A., additional, O’Keeffe, Derek, additional, Oksanen, A., additional, O’Meara, John M., additional, Ordasi, András, additional, Osborn, Hugh, additional, Ott, John J., additional, Parks, J. R., additional, Perez, Diego Rodriguez, additional, Petriew, Vance, additional, Pickard, R, additional, Pál, András, additional, Plavchan, P., additional, Pollacco, Don, additional, Nuñez, F. Pozo, additional, J. Pozuelos, F., additional, Rau, Steve, additional, Redfield, Seth, additional, Relles, Howard, additional, Ribas, Ignasi, additional, Richards, Jon, additional, Saario, Joonas L. O., additional, Safron, Emily J., additional, Sallai, J. Martin, additional, Sárneczky, Krisztián, additional, Schaefer, Bradley E., additional, Schumer, Clea F., additional, Schwartzendruber, Madison, additional, Siegel, Michael H., additional, Siemion, Andrew P. V., additional, Simmons, Brooke D., additional, Simon, Joshua D., additional, Simón-Díaz, S., additional, Sitko, Michael L., additional, Socas-Navarro, Hector, additional, Sódor, Á., additional, Starkey, Donn, additional, Steele, Iain A., additional, Stone, Geoff, additional, Strassmeier, Klaus G., additional, Street, R. A., additional, Sullivan, Tricia, additional, Suomela, J., additional, Swift, J. J., additional, Szabó, Gyula M., additional, Szabó, Róbert, additional, Szakáts, Róbert, additional, Szalai, Tamás, additional, Tanner, Angelle M., additional, Toledo-Padrón, B., additional, Tordai, Tamás, additional, Triaud, Amaury H. M. J., additional, Turner, Jake D., additional, Ulowetz, Joseph H., additional, Urbanik, Marian, additional, Vanaverbeke, Siegfried, additional, Vanderburg, Andrew, additional, Vida, Krisztián, additional, Vietje, Brad P., additional, Vinkó, József, additional, Braun, K. von, additional, Waagen, Elizabeth O., additional, Walsh, Dan, additional, Watson, Christopher A., additional, Weir, R. C., additional, Wenzel, Klaus, additional, Plaza, C. Westendorp, additional, Williamson, Michael W., additional, Wright, Jason T., additional, Wyatt, M. C., additional, Zheng, WeiKang, additional, and Zsidi, Gabriella, additional
Published: 2018
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226. Abundance ratios & ages of stellar populations in HARPS-GTO sample

Author: Mena, E. Delgado, primary, Tsantaki, M., additional, Zh. Adibekyan, V., additional, Sousa, S. G., additional, Santos, N. C., additional, Hernández, J. I. González, additional, and Israelian, G., additional
Published: 2017
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227. ESPRESSO Data Flow in operations: results of commissioning activities.

Author: Di Marcantonio, P., Sosnowska, D., Cupani, G., D’Odorico, V., Lovis, C., Segovia, A., Sousa, S., Hernández, J. I. González, Calderone, G., Cirami, R., Modigliani, A., Curto, G. Lo, Cristiani, S., Molaro, P., Pepe, F., and Mégevand, D.
Published: 2018
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228. HADES RV Programme with HARPS-N at TNG. VII. Rotation and activity of M-Dwarfs from time-series high-resolution spectroscopy of chromospheric indicators

Author: Mascareño, A. Suárez, Rebolo, R., Hernández, J. I. González, Toledo-Padrón, B., Perger, M., Ribas, I., Affer, L., Micela, G., Damasso, M., Maldonado, J., González-Alvarez, E., Leto, G., Pagano, I., Scandariato, G., Sozzetti, A., Lanza, A. F., Malavolta, L., Claudi, R., Cosentino, R., Desidera, S., Giacobbe, P., Maggio, A., Rainer, M., Esposito, M., Benatti, S., Pedani, M., Morales, J. C., Herrero, E., Lafarga, M., Rosich, A., Pinamonti, M., Mascareño, A. Suárez, Rebolo, R., Hernández, J. I. González, Toledo-Padrón, B., Perger, M., Ribas, I., Affer, L., Micela, G., Damasso, M., Maldonado, J., González-Alvarez, E., Leto, G., Pagano, I., Scandariato, G., Sozzetti, A., Lanza, A. F., Malavolta, L., Claudi, R., Cosentino, R., Desidera, S., Giacobbe, P., Maggio, A., Rainer, M., Esposito, M., Benatti, S., Pedani, M., Morales, J. C., Herrero, E., Lafarga, M., Rosich, A., and Pinamonti, M.
Abstract: We aim to investigate the presence of signatures of magnetic cycles and rotation on a sample of 71 early M-dwarfs from the HADES RV programme using high-resolution time-series spectroscopy of the Ca II H & K and Halpha chromospheric activity indicators, the radial velocity series, the parameters of the cross correlation function and the V-band photometry. We used mainly HARPS-N spectra, acquired over four years, and add HARPS spectra from the public ESO database and ASAS photometry light-curves as support data, extending the baseline of the observations of some stars up to 12 years. We provide log(R'hk) measurements for all the stars in the sample, cycle length measurements for 13 stars, rotation periods for 33 stars and we are able to measure the semi-amplitude of the radial velocity signal induced by rotation in 16 stars. We complement our work with previous results and confirm and refine the previously reported relationships between the mean level of chromospheric emission, measured by the log(R'hk), with the rotation period, and with the measured semi-amplitude of the activity induced radial velocity signal for early M-dwarfs. We searched for a possible relation between the measured rotation periods and the lengths of the magnetic cycle, finding a weak correlation between both quantities. Using previous v sin i measurements we estimated the inclinations of the star's poles to the line of sight for all the stars in the sample, and estimate the range of masses of the planets GJ 3998 b and c (2.5 - 4.9 Mearth and 6.3 - 12.5 Mearth), GJ 625 b (2.82 Mearth), GJ 3942 b (7.1 - 10.0 Mearth) and GJ 15A b (3.1 - 3.3 Mearth), assuming their orbits are coplanar with the stellar rotation., Comment: 19 pages, 16 figures, 10 tables
Published: 2017
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229. J0815+4729: A chemically primitive dwarf star in the Galactic Halo observed with Gran Telescopio Canarias

Author: Aguado, D. S., Hernández, J. I. González, Prieto, C. Allende, Rebolo, R., Aguado, D. S., Hernández, J. I. González, Prieto, C. Allende, and Rebolo, R.
Abstract: We report the discovery of the carbon-rich ultra metal-poor unevolved star J0815+4729. This dwarf star was selected from SDSS/BOSS as a metal-poor candidate and follow-up spectroscopic observations at medium-resolution were obtained with ISIS at William Herschel Telescope and OSIRIS at Gran Telescopio de Canarias. We use the FERRE code to derive the main stellar parameters, Teff=6215+-82 K, and logg=4.7+-0.5, an upper limit to the metallicity of [Fe/H]<~-5.8, and a carbon abundance of [C/Fe]>~+5.0, while [alpha/Fe]=0.4 is assumed. The metallicity upper limit is based on the Ca II K line, that at the resolving power of the OSIRIS spectrograph cannot be resolved from possible interstellar calcium. The star could be the most iron-poor unevolved star known, and is also amongst the ones with the largest overabundances of carbon. High-resolution spectroscopy of J0815+4729 will certainly help to derive other important element abundances, possibly providing new fundamental constraints on the early stages of the Universe, the formation of the first stars and the properties of the first supernovae., Comment: Accepted in ApJ Letters
Published: 2017
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230. The CARMENES search for exoplanets around M dwarfs - HD 147379b: A nearby Neptune in the temperate zone of an early-M dwarf

Author: Reiners, A., Ribas, I., Zechmeister, M., Caballero, J. A., Trifonov, T., Dreizler, S., Morales, J. C., Tal-Or, L., Lafarga, M., Quirrenbach, A., Amado, P. J., Kaminski, A., Jeffers, S. V., Aceituno, J., Béjar, V. J. S., Guàrdia, J., Guenther, E. W., Hagen, H. -J., Montes, D., Passegger, V. M., Seifert, W., Schweitzer, A., Cortés-Contreras, M., Abril, M., Alonso-Floriano, F. J., Eiff, M. Ammler-von, Antona, R., Anglada-Escudé, G., Anwand-Heerwart, H., Arroyo-Torres, B., Azzaro, M., Baroch, D., Barrado, D., Bauer, F. F., Becerril, S., Benítez, D., Berdiñas, Z. M., Bergond, G., Blümcke, M., Brinkmöller, M., del Burgo, C., Cano, J., Vázquez, M. C. Cárdenas, Casal, E., Cifuentes, C., Claret, A., Colomé, J., Czesla, S., Díez-Alonso, E., Feiz, C., Fernández, M., Ferro, I. M., Fuhrmeister, B., Galadí-Enríquez, D., Garcia-Piquer, A., Vargas, M. L. García, Gesa, L., Galera, V. Gómez, Hernández, J. I. González, González-Peinado, R., Grözinger, U., Grohnert, S., Guijarro, A., de Guindos, E., Gutiérrez-Soto, J., Hatzes, A. P., Hauschildt, P. H., Hedrosa, R. P., Helmling, J., Henning, Th., Hermelo, I., Arabí, R. Hernández, Castaño, L. Hernández, Hernando, F. Hernández, Herrero, E., Huber, A., Huke, P., Johnson, E. N., de Juan, E., Kim, M., Klein, R., Klüter, J., Klutsch, A., Kürster, M., Labarga, F., Lamert, A., Lampón, M., Lara, L. M., Laun, W., Lemke, U., Lenzen, R., Launhardt, R., del Fresno, M. López, López-González, M. J., López-Puertas, M., Salas, J. F. López, López-Santiago, J., Luque, R., Madinabeitia, H. Magán, Mall, U., Mancini, L., Mandel, H., Marfil, E., Molina, J. A. Marín, Fernández, D. Maroto, Martín, E. L., Martín-Ruiz, S., Marvin, C. J., Mathar, R. J., Mirabet, E., Moreno-Raya, M. E., Moya, A., Mundt, R., Nagel, E., Naranjo, V., Nortmann, L., Nowak, G., Ofir, A., Oreiro, R., Pallé, E., Panduro, J., Pascual, J., Pavlov, A., Pedraz, S., Pérez-Calpena, A., Medialdea, D. Pérez, Perger, M., Perryman, M. A. C., Pluto, M., Rabaza, O., Ramón, A., Rebolo, R., Redondo, P., Reffert, S., Reinhart, S., Rhode, P., Rix, H. -W., Rodler, F., Rodríguez, E., Rodríguez-López, C., Trinidad, A. Rodríguez, Rohloff, R. -R., Rosich, A., Sadegi, S., Sánchez-Blanco, E., Carrasco, M. A. Sánchez, Sánchez-López, A., Sanz-Forcada, J., Sarkis, P., Sarmiento, L. F., Schäfer, S., Schmitt, J. H. M. M., Schiller, J., Schöfer, P., Solano, E., Stahl, O., Strachan, J. B. P., Stürmer, J., Suárez, J. C., Tabernero, H. M., Tala, M., Tulloch, S. M., Ulbrich, R. -G., Veredas, G., Linares, J. I. Vico, Vilardell, F., Wagner, K., Winkler, J., Wolthoff, V., Xu, W., Yan, F., Osorio, M. R. Zapatero, Reiners, A., Ribas, I., Zechmeister, M., Caballero, J. A., Trifonov, T., Dreizler, S., Morales, J. C., Tal-Or, L., Lafarga, M., Quirrenbach, A., Amado, P. J., Kaminski, A., Jeffers, S. V., Aceituno, J., Béjar, V. J. S., Guàrdia, J., Guenther, E. W., Hagen, H. -J., Montes, D., Passegger, V. M., Seifert, W., Schweitzer, A., Cortés-Contreras, M., Abril, M., Alonso-Floriano, F. J., Eiff, M. Ammler-von, Antona, R., Anglada-Escudé, G., Anwand-Heerwart, H., Arroyo-Torres, B., Azzaro, M., Baroch, D., Barrado, D., Bauer, F. F., Becerril, S., Benítez, D., Berdiñas, Z. M., Bergond, G., Blümcke, M., Brinkmöller, M., del Burgo, C., Cano, J., Vázquez, M. C. Cárdenas, Casal, E., Cifuentes, C., Claret, A., Colomé, J., Czesla, S., Díez-Alonso, E., Feiz, C., Fernández, M., Ferro, I. M., Fuhrmeister, B., Galadí-Enríquez, D., Garcia-Piquer, A., Vargas, M. L. García, Gesa, L., Galera, V. Gómez, Hernández, J. I. González, González-Peinado, R., Grözinger, U., Grohnert, S., Guijarro, A., de Guindos, E., Gutiérrez-Soto, J., Hatzes, A. P., Hauschildt, P. H., Hedrosa, R. P., Helmling, J., Henning, Th., Hermelo, I., Arabí, R. Hernández, Castaño, L. Hernández, Hernando, F. Hernández, Herrero, E., Huber, A., Huke, P., Johnson, E. N., de Juan, E., Kim, M., Klein, R., Klüter, J., Klutsch, A., Kürster, M., Labarga, F., Lamert, A., Lampón, M., Lara, L. M., Laun, W., Lemke, U., Lenzen, R., Launhardt, R., del Fresno, M. López, López-González, M. J., López-Puertas, M., Salas, J. F. López, López-Santiago, J., Luque, R., Madinabeitia, H. Magán, Mall, U., Mancini, L., Mandel, H., Marfil, E., Molina, J. A. Marín, Fernández, D. Maroto, Martín, E. L., Martín-Ruiz, S., Marvin, C. J., Mathar, R. J., Mirabet, E., Moreno-Raya, M. E., Moya, A., Mundt, R., Nagel, E., Naranjo, V., Nortmann, L., Nowak, G., Ofir, A., Oreiro, R., Pallé, E., Panduro, J., Pascual, J., Pavlov, A., Pedraz, S., Pérez-Calpena, A., Medialdea, D. Pérez, Perger, M., Perryman, M. A. C., Pluto, M., Rabaza, O., Ramón, A., Rebolo, R., Redondo, P., Reffert, S., Reinhart, S., Rhode, P., Rix, H. -W., Rodler, F., Rodríguez, E., Rodríguez-López, C., Trinidad, A. Rodríguez, Rohloff, R. -R., Rosich, A., Sadegi, S., Sánchez-Blanco, E., Carrasco, M. A. Sánchez, Sánchez-López, A., Sanz-Forcada, J., Sarkis, P., Sarmiento, L. F., Schäfer, S., Schmitt, J. H. M. M., Schiller, J., Schöfer, P., Solano, E., Stahl, O., Strachan, J. B. P., Stürmer, J., Suárez, J. C., Tabernero, H. M., Tala, M., Tulloch, S. M., Ulbrich, R. -G., Veredas, G., Linares, J. I. Vico, Vilardell, F., Wagner, K., Winkler, J., Wolthoff, V., Xu, W., Yan, F., and Osorio, M. R. Zapatero
Abstract: We report on the first star discovered to host a planet detected by radial velocity (RV) observations obtained within the CARMENES survey for exoplanets around M dwarfs. HD 147379 ($V = 8.9$ mag, $M = 0.58 \pm 0.08$ M$_{\odot}$), a bright M0.0V star at a distance of 10.7 pc, is found to undergo periodic RV variations with a semi-amplitude of $K = 5.1\pm0.4$ m s$^{-1}$ and a period of $P = 86.54\pm0.06$ d. The RV signal is found in our CARMENES data, which were taken between 2016 and 2017, and is supported by HIRES/Keck observations that were obtained since 2000. The RV variations are interpreted as resulting from a planet of minimum mass $m_{\rm p}\sin{i} = 25 \pm 2$ M$_{\oplus}$, 1.5 times the mass of Neptune, with an orbital semi-major axis $a = 0.32$ au and low eccentricity ($e < 0.13$). HD 147379b is orbiting inside the temperate zone around the star, where water could exist in liquid form. The RV time-series and various spectroscopic indicators show additional hints of variations at an approximate period of 21.1d (and its first harmonic), which we attribute to the rotation period of the star., Comment: accepted for publication as A&A Letter
Published: 2017
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231. The RoPES project with HARPS and HARPS-N. I. A system of super-Earths orbiting the moderately active K-dwarf HD 176986

Author: Mascareño, A. Suárez, Hernández, J. I. González, Rebolo, R., Velasco, S., Toledo-Padrón, B., Udry, S., Motalebi, F., Ségrasan, D., Wyttenbach, A., Mayor, M., Pepe, F., Lovis, C., Santos, N. C., Figueira, P., Esposito, M., Mascareño, A. Suárez, Hernández, J. I. González, Rebolo, R., Velasco, S., Toledo-Padrón, B., Udry, S., Motalebi, F., Ségrasan, D., Wyttenbach, A., Mayor, M., Pepe, F., Lovis, C., Santos, N. C., Figueira, P., and Esposito, M.
Abstract: We report the discovery of a system of two super-Earths orbiting the moderately active K-dwarf HD 176986. This work is part of the RoPES RV program of G- and K-type stars, which combines radial velocities (RVs) from the HARPS and HARPS-N spectrographs to search for short-period terrestrial planets. HD 176986 b and c are super-Earth planets with masses of 5.74 and 9.18 M$_{\oplus}$, orbital periods of 6.49 and 16.82 days, and distances of 0.063 and 0.119 AU in orbits that are consistent with circular. The host star is a K2.5 dwarf, and despite its modest level of chromospheric activity (log(R'hk) = - 4.90 +- 0.04), it shows a complex activity pattern. Along with the discovery of the planets, we study the magnetic cycle and rotation of the star. HD 176986 proves to be suitable for testing the available RV analysis technique and further our understanding of stellar activity., Comment: 21 pages, 24 figures, 7 tables
Published: 2017
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232. The CARMENES search for exoplanets around M dwarfs: High-resolution optical and near-infrared spectroscopy of 324 survey stars

Author: Reiners, A., Zechmeister, M., Caballero, J. A., Ribas, I., Morales, J. C., Jeffers, S. V., Schöfer, P., Tal-Or, L., Quirrenbach, A., Amado, P. J., Kaminski, A., Seifert, W., Abril, M., Aceituno, J., Alonso-Floriano, F. J., Eiff, M. Ammler-von, Antona, R., Anglada-Escudé, G., Anwand-Heerwart, H., Arroyo-Torres, B., Azzaro, M., Baroch, D., Barrado, D., Bauer, F. F., Becerril, S., Béjar, V. J. S., Benítez, D., Berdiñas, Z. M., Bergond, G., Blümcke, M., Brinkmöller, M., del Burgo, C., Cano, J., Vázquez, M. C. Cárdenas, Casal, E., Cifuentes, C., Claret, A., Colomé, J., Cortés-Contreras, M., Czesla, S., Díez-Alonso, E., Dreizler, S., Feiz, C., Fernández, M., Ferro, I. M., Fuhrmeister, B., Galadí-Enríquez, D., Garcia-Piquer, A., Vargas, M. L. García, Gesa, L., Gómez, V., Galera, Hernández, J. I. González, González-Peinado, R., Grözinger, U., Grohnert, S., Guàrdia, J., Guenther, E. W., Guijarro, A., de Guindos, E., Gutiérrez-Soto, J., Hagen, H. -J., Hatzes, A. P., Hauschildt, P. H., Hedrosa, R. P., Helmling, J., Henning, Th., Hermelo, I., Arabí, R. Hernández, Castaño, L. Hernández, Hernando, F. Hernández, Herrero, E., Huber, A., Huke, P., Johnson, E., de Juan, E., Kim, M., Klein, R., Klüter, J., Klutsch, A., Kürster, M., Lafarga, M., Lamert, A., Lampón, M., Lara, L. M., Laun, W., Lemke, U., Lenzen, R., Launhardt, R., del Fresno, M. López, López-González, J., López-Puertas, M., Salas, J. F. López, López-Santiago, J., Luque, R., Madinabeitia, H. Magán, Mall, U., Mancini, L., Mandel, H., Marfil, E., Molina, J. A. Marín, Maroto, D., Fernández, Martín, E. L., Martín-Ruiz, S., Marvin, C. J., Mathar, R. J., Mirabet, E., Montes, D., Moreno-Raya, M. E., Moya, A., Mundt, R., Nagel, E., Naranjo, V., Nortmann, L., Nowak, G., Ofir, A., Oreiro, R., Pallé, E., Panduro, J., Pascual, J., Passegger, V. M., Pavlov, A., Pedraz, S., Pérez-Calpena, A., Medialdea, D. Pérez, Perger, M., Perryman, M. A. C., Pluto, M., Rabaza, O., Ramón, A., Rebolo, R., Redondo, P., Reffert, S., Reinhart, S., Rhode, P., Rix, H. -W., Rodler, F., Rodríguez, E., Rodríguez-López, C., Trinidad, A. Rodríguez, Rohloff, R. -R., Rosich, A., Sadegi, S., Sánchez-Blanco, E., Carrasco, M. A. Sánchez, Sánchez-López, A., Sanz-Forcada, J., Sarkis, P., Sarmiento, L. F., Schäfer, S., Schmitt, J. H. M. M., Schiller, J., Schweitzer, A., Solano, E., Stahl, O., Strachan, J. B. P., Stürmer, J., Suárez, J. C., Tabernero, H. M., Tala, M., Trifonov, T., Tulloch, S. M., Ulbrich, R. G., Veredas, G., Linares, J. I. Vico, Vilardell, F., Wagner, K., Winkler, J., Wolthoff, V., Xu, W., Yan, F., Osorio, M. R. Zapatero, Reiners, A., Zechmeister, M., Caballero, J. A., Ribas, I., Morales, J. C., Jeffers, S. V., Schöfer, P., Tal-Or, L., Quirrenbach, A., Amado, P. J., Kaminski, A., Seifert, W., Abril, M., Aceituno, J., Alonso-Floriano, F. J., Eiff, M. Ammler-von, Antona, R., Anglada-Escudé, G., Anwand-Heerwart, H., Arroyo-Torres, B., Azzaro, M., Baroch, D., Barrado, D., Bauer, F. F., Becerril, S., Béjar, V. J. S., Benítez, D., Berdiñas, Z. M., Bergond, G., Blümcke, M., Brinkmöller, M., del Burgo, C., Cano, J., Vázquez, M. C. Cárdenas, Casal, E., Cifuentes, C., Claret, A., Colomé, J., Cortés-Contreras, M., Czesla, S., Díez-Alonso, E., Dreizler, S., Feiz, C., Fernández, M., Ferro, I. M., Fuhrmeister, B., Galadí-Enríquez, D., Garcia-Piquer, A., Vargas, M. L. García, Gesa, L., Gómez, V., Galera, Hernández, J. I. González, González-Peinado, R., Grözinger, U., Grohnert, S., Guàrdia, J., Guenther, E. W., Guijarro, A., de Guindos, E., Gutiérrez-Soto, J., Hagen, H. -J., Hatzes, A. P., Hauschildt, P. H., Hedrosa, R. P., Helmling, J., Henning, Th., Hermelo, I., Arabí, R. Hernández, Castaño, L. Hernández, Hernando, F. Hernández, Herrero, E., Huber, A., Huke, P., Johnson, E., de Juan, E., Kim, M., Klein, R., Klüter, J., Klutsch, A., Kürster, M., Lafarga, M., Lamert, A., Lampón, M., Lara, L. M., Laun, W., Lemke, U., Lenzen, R., Launhardt, R., del Fresno, M. López, López-González, J., López-Puertas, M., Salas, J. F. López, López-Santiago, J., Luque, R., Madinabeitia, H. Magán, Mall, U., Mancini, L., Mandel, H., Marfil, E., Molina, J. A. Marín, Maroto, D., Fernández, Martín, E. L., Martín-Ruiz, S., Marvin, C. J., Mathar, R. J., Mirabet, E., Montes, D., Moreno-Raya, M. E., Moya, A., Mundt, R., Nagel, E., Naranjo, V., Nortmann, L., Nowak, G., Ofir, A., Oreiro, R., Pallé, E., Panduro, J., Pascual, J., Passegger, V. M., Pavlov, A., Pedraz, S., Pérez-Calpena, A., Medialdea, D. Pérez, Perger, M., Perryman, M. A. C., Pluto, M., Rabaza, O., Ramón, A., Rebolo, R., Redondo, P., Reffert, S., Reinhart, S., Rhode, P., Rix, H. -W., Rodler, F., Rodríguez, E., Rodríguez-López, C., Trinidad, A. Rodríguez, Rohloff, R. -R., Rosich, A., Sadegi, S., Sánchez-Blanco, E., Carrasco, M. A. Sánchez, Sánchez-López, A., Sanz-Forcada, J., Sarkis, P., Sarmiento, L. F., Schäfer, S., Schmitt, J. H. M. M., Schiller, J., Schweitzer, A., Solano, E., Stahl, O., Strachan, J. B. P., Stürmer, J., Suárez, J. C., Tabernero, H. M., Tala, M., Trifonov, T., Tulloch, S. M., Ulbrich, R. G., Veredas, G., Linares, J. I. Vico, Vilardell, F., Wagner, K., Winkler, J., Wolthoff, V., Xu, W., Yan, F., and Osorio, M. R. Zapatero
Abstract: The CARMENES radial velocity (RV) survey is observing 324 M dwarfs to search for any orbiting planets. In this paper, we present the survey sample by publishing one CARMENES spectrum for each M dwarf. These spectra cover the wavelength range 520--1710nm at a resolution of at least $R > 80,000$, and we measure its RV, H$\alpha$ emission, and projected rotation velocity. We present an atlas of high-resolution M-dwarf spectra and compare the spectra to atmospheric models. To quantify the RV precision that can be achieved in low-mass stars over the CARMENES wavelength range, we analyze our empirical information on the RV precision from more than 6500 observations. We compare our high-resolution M-dwarf spectra to atmospheric models where we determine the spectroscopic RV information content, $Q$, and signal-to-noise ratio. We find that for all M-type dwarfs, the highest RV precision can be reached in the wavelength range 700--900nm. Observations at longer wavelengths are equally precise only at the very latest spectral types (M8 and M9). We demonstrate that in this spectroscopic range, the large amount of absorption features compensates for the intrinsic faintness of an M7 star. To reach an RV precision of 1ms$^{-1}$ in very low mass M dwarfs at longer wavelengths likely requires the use of a 10m class telescope. For spectral types M6 and earlier, the combination of a red visual and a near-infrared spectrograph is ideal to search for low-mass planets and to distinguish between planets and stellar variability. At a 4m class telescope, an instrument like CARMENES has the potential to push the RV precision well below the typical jitter level of 3-4ms$^{-1}$., Comment: accepted for publication in A&A, 13 pages plus 40 pages spectral atlas, first 10 atlas pages are reduced in quality to fit arXiv size limit; one CARMENES spectrum for each of the 324 stars is published in electronic format at http://carmenes.cab.inta-csic.es
Published: 2017
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233. The Pristine survey III: Spectroscopic confirmation of an efficient search for extremely metal-poor stars

Author: Youakim, K., Starkenburg, E., Aguado, D. S., Martin, N. F., Fouesneau, M., Hernández, J. I. González, Prieto, C. Allende, Bonifacio, P., Gentile, M., Kielty, C., Côté, P., Jablonka, P., McConnachie, A., Janssen, R. Sánchez, Tolstoy, E., Venn, K., Youakim, K., Starkenburg, E., Aguado, D. S., Martin, N. F., Fouesneau, M., Hernández, J. I. González, Prieto, C. Allende, Bonifacio, P., Gentile, M., Kielty, C., Côté, P., Jablonka, P., McConnachie, A., Janssen, R. Sánchez, Tolstoy, E., and Venn, K.
Abstract: The Pristine survey is a narrow-band, photometric survey focused around the wavelength region of the Ca II H & K absorption lines, designed to efficiently search for extremely metal-poor stars. In this work, we use the first results of a medium-resolution spectroscopic follow-up to refine the selection criteria for finding extremely metal-poor stars ($\textrm{[Fe/H]} \leq -3.0$) in the Pristine survey. We consider methods by which stars can be selected from available broad-band and infrared photometry plus the additional Pristine narrow-band photometry. The spectroscopic sample presented in this paper consists of 205 stars in the magnitude range $14 < V < 18$. Applying the photometric selection criteria cuts the sample down to 149 stars, and from these we report a success rate of 70% for finding stars with $\textrm{[Fe/H]} \leq -2.5$ and 22% for finding stars with $\textrm{[Fe/H]} \leq -3.0$. These statistics compare favourably with other surveys that search for extremely metal-poor stars, namely an improvement by a factor of $\sim 4-5$ for recovering stars with $\textrm{[Fe/H]} \leq -3.0$. In addition, Pristine covers a fainter magnitude range than its predecessors, and can thus probe deeper into the Galactic halo., Comment: 14 pages, 6 figures, 4 tables, full version of Table 1 available on-line only, accepted for publication in MNRAS
Published: 2017
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234. The CARMENES search for exoplanets around M dwarfs. First visual-channel radial-velocity measurements and orbital parameter updates of seven M-dwarf planetary systems

Author: Trifonov, T., Kürster, M., Zechmeister, M., Tal-Or, L., Caballero, J. A., Quirrenbach, A., Amado, P. J., Ribas, I., Reiners, A., Reffert, S., Dreizler, S., Hatzes, A. P., Kaminski, A., Launhardt, R., Henning, Th., Montes, D., Béjar, V. J. S., Mundt, R., Pavlov, A., Schmitt, J. H. M. M., Seifert, W., Morales, J. C., Nowak, G., Jeffers, S. V., Rodríguez-López, C., del Burgo, C., Anglada-Escudé, G., López-Santiago, J., Mathar, R. J., Eiff, M. Ammler-von, Guenther, E. W., Barrado, D., Hernández, J. I. González, Mancini, L., Stürmer, J., Abril, M., Aceituno, J., Alonso-Floriano, F. J., Antona, R., Anwand-Heerwart, H., Arroyo-Torres, B., Azzaro, M., Baroch, D., Bauer, F. F., Becerril, S., Benítez, D., Berdiñas, Z. M., Bergond, G., Blümcke, M., Brinkmöller, M., Cano, J., Vázquez, M. C. Cárdenas, Casal, E., Cifuentes, C., Claret, A., Colomé, J., Cortés-Contreras, M., Czesla, S., Díez-Alonso, E., Feiz, C., Fernández, M., Ferro, I. M., Fuhrmeister, B., Galadí-Enríquez, D., Garcia-Piquer, A., Vargas, M. L. García, Gesa, L., Galera, V. Gómez, González-Peinado, R., Grözinger, U., Grohnert, S., Guàrdia, J., Guijarro, A., de Guindos, E., Gutiérrez-Soto, J., Hagen, H. -J., Hauschildt, P. H., Hedrosa, R. P., Helmling, J., Hermelo, I., Arabí, R. Hernández, Castaño, L. Hernández, Hernando, F. Hernández, Herrero, E., Huber, A., Huke, P., Johnson, E., de Juan, E., Kim, M., Klein, R., Klüter, J., Klutsch, A., Lafarga, M., Lampón, M., Lara, L. M., Laun, W., Lemke, U., Lenzen, R., del Fresno, M. López, López-González, J., López-Puertas, M., Salas, J. F. López, Luque, R., Madinabeitia, H. Magán, Mall, U., Mandel, H., Marfil, E., Molina, J. A. Marín, Fernández, D. Maroto, Martín, E. L., Martín-Ruiz, S., Marvin, C. J., Mirabet, E., Moya, A., Moreno-Raya, M. E., Nagel, E., Naranjo, V., Nortmann, L., Ofir, A., Oreiro, R., Pallé, E., Panduro, J., Pascual, J., Passegger, V. M., Pedraz, S., Pérez-Calpena, A., Medialdea, D. Pérez, Perger, M., Perryman, M. A. C., Pluto, M., Rabaza, O., Ramón, A., Rebolo, R., Redondo, P., Reinhardt, S., Rhode, P., Rix, H. -W., Rodler, F., Rodríguez, E., Trinidad, A. Rodríguez, Rohloff, R. -R., Rosich, A., Sadegi, S., Sánchez-Blanco, E., Carrasco, M. A. Sánchez, Sánchez-López, A., Sanz-Forcada, J., Sarkis, P., Sarmiento, L. F., Schäfer, S., Schiller, J., Schöfer, P., Schweitzer, A., Solano, E., Stahl, O., Strachan, J. B. P., Suárez, J. C., Tabernero, H. M., Tala, M., Tulloch, S. M., Veredas, G., Linares, J. I. Vico, Vilardell, F., Wagner, K., Winkler, J., Wolthoff, V., Xu, W., Yan, F., Osorio, M. R. Zapatero, Trifonov, T., Kürster, M., Zechmeister, M., Tal-Or, L., Caballero, J. A., Quirrenbach, A., Amado, P. J., Ribas, I., Reiners, A., Reffert, S., Dreizler, S., Hatzes, A. P., Kaminski, A., Launhardt, R., Henning, Th., Montes, D., Béjar, V. J. S., Mundt, R., Pavlov, A., Schmitt, J. H. M. M., Seifert, W., Morales, J. C., Nowak, G., Jeffers, S. V., Rodríguez-López, C., del Burgo, C., Anglada-Escudé, G., López-Santiago, J., Mathar, R. J., Eiff, M. Ammler-von, Guenther, E. W., Barrado, D., Hernández, J. I. González, Mancini, L., Stürmer, J., Abril, M., Aceituno, J., Alonso-Floriano, F. J., Antona, R., Anwand-Heerwart, H., Arroyo-Torres, B., Azzaro, M., Baroch, D., Bauer, F. F., Becerril, S., Benítez, D., Berdiñas, Z. M., Bergond, G., Blümcke, M., Brinkmöller, M., Cano, J., Vázquez, M. C. Cárdenas, Casal, E., Cifuentes, C., Claret, A., Colomé, J., Cortés-Contreras, M., Czesla, S., Díez-Alonso, E., Feiz, C., Fernández, M., Ferro, I. M., Fuhrmeister, B., Galadí-Enríquez, D., Garcia-Piquer, A., Vargas, M. L. García, Gesa, L., Galera, V. Gómez, González-Peinado, R., Grözinger, U., Grohnert, S., Guàrdia, J., Guijarro, A., de Guindos, E., Gutiérrez-Soto, J., Hagen, H. -J., Hauschildt, P. H., Hedrosa, R. P., Helmling, J., Hermelo, I., Arabí, R. Hernández, Castaño, L. Hernández, Hernando, F. Hernández, Herrero, E., Huber, A., Huke, P., Johnson, E., de Juan, E., Kim, M., Klein, R., Klüter, J., Klutsch, A., Lafarga, M., Lampón, M., Lara, L. M., Laun, W., Lemke, U., Lenzen, R., del Fresno, M. López, López-González, J., López-Puertas, M., Salas, J. F. López, Luque, R., Madinabeitia, H. Magán, Mall, U., Mandel, H., Marfil, E., Molina, J. A. Marín, Fernández, D. Maroto, Martín, E. L., Martín-Ruiz, S., Marvin, C. J., Mirabet, E., Moya, A., Moreno-Raya, M. E., Nagel, E., Naranjo, V., Nortmann, L., Ofir, A., Oreiro, R., Pallé, E., Panduro, J., Pascual, J., Passegger, V. M., Pedraz, S., Pérez-Calpena, A., Medialdea, D. Pérez, Perger, M., Perryman, M. A. C., Pluto, M., Rabaza, O., Ramón, A., Rebolo, R., Redondo, P., Reinhardt, S., Rhode, P., Rix, H. -W., Rodler, F., Rodríguez, E., Trinidad, A. Rodríguez, Rohloff, R. -R., Rosich, A., Sadegi, S., Sánchez-Blanco, E., Carrasco, M. A. Sánchez, Sánchez-López, A., Sanz-Forcada, J., Sarkis, P., Sarmiento, L. F., Schäfer, S., Schiller, J., Schöfer, P., Schweitzer, A., Solano, E., Stahl, O., Strachan, J. B. P., Suárez, J. C., Tabernero, H. M., Tala, M., Tulloch, S. M., Veredas, G., Linares, J. I. Vico, Vilardell, F., Wagner, K., Winkler, J., Wolthoff, V., Xu, W., Yan, F., and Osorio, M. R. Zapatero
Abstract: Context: The main goal of the CARMENES survey is to find Earth-mass planets around nearby M-dwarf stars. Seven M-dwarfs included in the CARMENES sample had been observed before with HIRES and HARPS and either were reported to have one short period planetary companion (GJ15A, GJ176, GJ436, GJ536 and GJ1148) or are multiple planetary systems (GJ581 and GJ876). Aims: We aim to report new precise optical radial velocity measurements for these planet hosts and test the overall capabilities of CARMENES. Methods: We combined our CARMENES precise Doppler measurements with those available from HIRES and HARPS and derived new orbital parameters for the systems. Bona-fide single planet systems are fitted with a Keplerian model. The multiple planet systems were analyzed using a self-consistent dynamical model and their best fit orbits were tested for long-term stability. Results: We confirm or provide supportive arguments for planets around all the investigated stars except for GJ15A, for which we find that the post-discovery HIRES data and our CARMENES data do not show a signal at 11.4 days. Although we cannot confirm the super-Earth planet GJ15Ab, we show evidence for a possible long-period ($P_{\rm c}$ = 7025$_{-629}^{+972}$ d) Saturn-mass ($m_{\rm c} \sin i$ = 51.8$_{-5.8}^{+5.5}M_\oplus$) planet around GJ15A. In addition, based on our CARMENES and HIRES data we discover a second planet around GJ1148, for which we estimate a period $P_{\rm c}$ = 532.6$_{-2.5}^{+4.1}$ d, eccentricity $e_{\rm c}$ = 0.34$_{-0.06}^{+0.05}$ and minimum mass $m_{\rm c} \sin i$ = 68.1$_{-2.2}^{+4.9}M_\oplus$. Conclusions: The CARMENES optical radial velocities have similar precision and overall scatter when compared to the Doppler measurements conducted with HARPS and HIRES. We conclude that CARMENES is an instrument that is up to the challenge of discovering rocky planets around low-mass stars., Comment: Accepted for publication in A&A, 24 pages, 16 figures, 14 tables
Published: 2017
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235. HADES RV Programme with HARPS-N at TNG VI. GJ 3942 b behind dominant activity signals

Author: Perger, M., Ribas, I., Damasso, M., Morales, J. C., Affer, L., Mascareño, A. Suárez, Micela, G., Maldonado, J., Hernández, J. I. González, Rebolo, R., Scandariato, G., Leto, G., Sanchez, R. Zanmar, Benatti, S., Bignamini, A., Borsa, F., Carbognani, A., Claudi, R., Desidera, S., Esposito, M., Lafarga, M., Fiorenzano, A. F. Martinez, Herrero, E., Molinari, E., Nascimbeni, V., Pagano, I., Pedani, M., Poretti, E., Rainer, M., Rosich, A., Sozzetti, A., Toledo-Padrón, B., Perger, M., Ribas, I., Damasso, M., Morales, J. C., Affer, L., Mascareño, A. Suárez, Micela, G., Maldonado, J., Hernández, J. I. González, Rebolo, R., Scandariato, G., Leto, G., Sanchez, R. Zanmar, Benatti, S., Bignamini, A., Borsa, F., Carbognani, A., Claudi, R., Desidera, S., Esposito, M., Lafarga, M., Fiorenzano, A. F. Martinez, Herrero, E., Molinari, E., Nascimbeni, V., Pagano, I., Pedani, M., Poretti, E., Rainer, M., Rosich, A., Sozzetti, A., and Toledo-Padrón, B.
Abstract: Short- to mid-term magnetic phenomena on the stellar surface of M-type stars cannot only resemble the effects of planets in radial velocity data, but also may hide them. We analyze 145 spectroscopic HARPS-N observations of GJ 3942 taken over the past five years and additional photometry to disentangle stellar activity effects from genuine Doppler signals as a result of the orbital motion of the star around the common barycenter with its planet. To achieve this, we use the common methods of pre-whitening, and treat the correlated red noise by a first-order moving average term and by Gaussian-process regression following an MCMC analysis. We identify the rotational period of the star at 16.3 days and discover a new super-Earth, GJ 3942 b, with an orbital period of 6.9 days and a minimum mass of 7.1 Me. An additional signal in the periodogram of the residuals is present but we cannot claim it to be related to a second planet with sufficient significance at this point. If confirmed, such planet candidate would have a minimum mass of 6.3 Me and a period of 10.4 days, which might indicate a 3:2 mean-motion resonance with the inner planet.
Published: 2017
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236. Abundance ratios \& ages of stellar populations in HARPS-GTO sample

Author: Mena, E. Delgado, Tsantaki, M., Adibekyan, V. Zh., Sousa, S. G., Santos, N. C., Hernández, J. I. González, Israelian, G., Mena, E. Delgado, Tsantaki, M., Adibekyan, V. Zh., Sousa, S. G., Santos, N. C., Hernández, J. I. González, and Israelian, G.
Abstract: In this work we present chemical abundances of heavy elements (Z$>$28) for a homogeneous sample of 1059 stars from HARPS planet search program. We also derive ages using parallaxes from Hipparcos and Gaia DR1 to compare the results. We study the [X/Fe] ratios for different populations and compare them with models of Galactic chemical evolution. We find that thick disk stars are chemically disjunt for Zn and Eu. Moreover, the high-alpha metal-rich population presents an interesting behaviour, with clear overabundances of Cu and Zn and lower abundances of Y and Ba with respect to thin disk stars. Several abundance ratios present a significant correlation with age for chemically separated thin disk stars (regardless of their metallicity) but thick disk stars do not present that behaviour. Moreover, at supersolar metallicities the trends with age tend to be weaker for several elements., Comment: 4 pages, to appear in the Proceedings of IAU Symp. 330: Astrometry and Astrophysics in the Gaia Sky
Published: 2017
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237. New ultra metal-poor stars from SDSS: follow-up GTC medium-resolution spectroscopy

Author: Aguado, D. S., Prieto, C. Allende, Hernández, J. I. González, Rebolo, R., Caffau, E., Aguado, D. S., Prieto, C. Allende, Hernández, J. I. González, Rebolo, R., and Caffau, E.
Abstract: Context. The first generation of stars formed in the Galaxy left behind the chemical signatures of their nucleosynthesis in the interstellar medium, visible today in the atmospheres of low-mass stars formed afterwards. Sampling the chemistry of low-mass provides insight into the first stars. Aims. We aim to increase the samples of stars with extremely low metal abundances, identifying ultra metal-poor stars from spectra with modest spectral resolution and signal-to-noise ratio (S/N). Achieving this goal involves deriving reliable metallicities and carbon abundances from such spectra. Methods. We carry-out follow-up observations of faint, V>19, metal-poor candidates selected from SDSS spectroscopy and observed with OSIRIS at GTC. The SDSS and follow-up OSIRIS spectra have been analyzed using the FERRE code to derive effective temperatures, surface gravities, metallicities and carbon abundances. In addition, a well-known extremely metal-poor star has been included in our sample to calibrate the analysis methodology. Results. We have observed and analyzed five metal-poor candidates from modest-quality SDSS spectra. All stars in our sample have been confirmed as extremely metal-poor stars, in the [Fe/H]<-3.3 regime. We report the recognition of J173403+644632, a carbon-enhanced ultra metal-poor dwarf star with [Fe/H]=-4.3 and [C/Fe]=+3.1., Comment: Accepted for publication in A&A
Published: 2017
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238. Erratum: Rotation periods of late-type dwarf stars from time series high-resolution spectroscopy of chromospheric indicators

Author: Mascareño, A. Suárez, primary, Rebolo, R., additional, Hernández, J. I. González, additional, and Esposito, M., additional
Published: 2016
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239. EChO

Author: Tinetti, G., Beaulieu, J. P., Henning, T., Meyer, M., Micela, G., Ribas, I., Stam, D., Swain, M., Krause, O., Ollivier, M., Pace, E., Swinyard, B., Aylward, A., van Boekel, R., Coradini, A., Encrenaz, T., Snellen, I., Zapatero-Osorio, M. R., Bouwman, J., Cho, J. Y-K., Coudé de Foresto, V., Guillot, T., Lopez-Morales, M., Mueller-Wodarg, I., Palle, E., Selsis, F., Sozzetti, A., Ade, P. A. R., Achilleos, N., Adriani, A., Agnor, C. B., Afonso, C., Prieto, C. Allende, Bakos, G., Barber, R. J., Barlow, M., Batista, V., Bernath, P., Bézard, B., Bordé, P., Brown, L. R., Cassan, A., Cavarroc, C., Ciaravella, A., Cockell, C., Coustenis, A., Danielski, C., Decin, L., Kok, R. De, Demangeon, O., Deroo, P., Doel, P., Drossart, P., Fletcher, L. N., Focardi, M., Forget, F., Fossey, S., Fouqué, P., Frith, J., Galand, M., Gaulme, P., Hernández, J. I. González, Grasset, O., Grassi, D., Grenfell, J. L., Griffin, M. J., Griffith, C. A., Grözinger, U., Guedel, M., Guio, P., Hainaut, O., Hargreaves, R., Hauschildt, P. H., Heng, Kevin, Heyrovsky, D., Hueso, R., Irwin, P., Kaltenegger, L., Kervella, P., Kipping, D., Koskinen, T. T., Kovács, G., La Barbera, A., Lammer, H., Lellouch, E., Leto, G., Lopez Morales, M., Lopez Valverde, M. A., Lopez-Puertas, M., Lovis, C., Maggio, A., Maillard, J. P., Maldonado Prado, J., Marquette, J. B., Martin-Torres, F. J., Maxted, P., Miller, S., Molinari, S., Montes, D., Moro-Martin, A., Moses, J. I., Mousis, O., Nguyen Tuong, N., Nelson, R., Orton, G. S., Pantin, E., Pascale, E., Pezzuto, S., Pinfield, D., Poretti, E., Prinja, R., Prisinzano, L., Rees, J. M., Reiners, A., Samuel, B., Sánchez-Lavega, A., Forcada, J. Sanz, Sasselov, D., Savini, G., Sicardy, B., Smith, A., Stixrude, L., Strazzulla, G., Tennyson, J., Tessenyi, M., Vasisht, G., Vinatier, S., Viti, S., Waldmann, I., White, G. J., Widemann, T., Wordsworth, R., Yelle, R., Yung, Y., and Yurchenko, S. N.
Subjects: 530 Physics, 520 Astronomy, Astrophysics::Earth and Planetary Astrophysics
Abstract: A dedicated mission to investigate exoplanetary atmospheres represents a major milestone in our quest to understand our place in the universe by placing our Solar System in context and by addressing the suitability of planets for the presence of life. EChO—the Exoplanet Characterisation Observatory—is a mission concept specifically geared for this purpose. EChO will provide simultaneous, multi-wavelength spectroscopic observations on a stable platform that will allow very long exposures. The use of passive cooling, few moving parts and well established technology gives a low-risk and potentially long-lived mission. EChO will build on observations by Hubble, Spitzer and ground-based telescopes, which discovered the first molecules and atoms in exoplanetary atmospheres. However, EChO’s configuration and specifications are designed to study a number of systems in a consistent manner that will eliminate the ambiguities affecting prior observations. EChO will simultaneously observe a broad enough spectral region—from the visible to the mid-infrared—to constrain from one single spectrum the temperature structure of the atmosphere, the abundances of the major carbon and oxygen bearing species, the expected photochemically-produced species and magnetospheric signatures. The spectral range and resolution are tailored to separate bands belonging to up to 30 molecules and retrieve the composition and temperature structure of planetary atmospheres. The target list for EChO includes planets ranging from Jupiter-sized with equilibrium temperatures T eq up to 2,000 K, to those of a few Earth masses, with T eq \u223c 300 K. The list will include planets with no Solar System analog, such as the recently discovered planets GJ1214b, whose density lies between that of terrestrial and gaseous planets, or the rocky-iron planet 55 Cnc e, with day-side temperature close to 3,000 K. As the number of detected exoplanets is growing rapidly each year, and the mass and radius of those detected steadily decreases, the target list will be constantly adjusted to include the most interesting systems. We have baselined a dispersive spectrograph design covering continuously the 0.4–16 μm spectral range in 6 channels (1 in the visible, 5 in the InfraRed), which allows the spectral resolution to be adapted from several tens to several hundreds, depending on the target brightness. The instrument will be mounted behind a 1.5 m class telescope, passively cooled to 50 K, with the instrument structure and optics passively cooled to \u223c45 K. EChO will be placed in a grand halo orbit around L2. This orbit, in combination with an optimised thermal shield design, provides a highly stable thermal environment and a high degree of visibility of the sky to observe repeatedly several tens of targets over the year. Both the baseline and alternative designs have been evaluated and no critical items with Technology Readiness Level (TRL) less than 4–5 have been identified. We have also undertaken a first-order cost and development plan analysis and find that EChO is easily compatible with the ESA M-class mission framework.
Published: 2012
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240. Extremely fast orbital decay of the black hole X-ray binary Nova Muscae 1991.

Author: Hernández, J. I. González, Suárez-Andrés, L., Rebolo, R., and Casares, J.
Subjects: SPECTRUM analysis, BINARY black holes, VERY large telescopes, EVENT horizon (Relativity), BLACK holes
Abstract: We present new medium-resolution spectroscopic observations of the black hole X-ray binary Nova Muscae 1991 taken with X-Shooter spectrograph installed at the 8.2-m VLT telescope. These observations allow us to measure the time of inferior conjunction of the secondary star with the black hole in this system that, together with previous measurements, yield an orbital period decay of Ṗ =−20.7±12.7 ms yr-1 (−24.5 ± 15.1 μs per orbital cycle). This is significantly faster than those previously measured in the other black hole X-ray binaries A0620-00 and XTE J1118+480. No standard black hole X-ray binary evolutionary model is able to explain this extremely fast orbital decay. At this rate, the secondary star would reach the event horizon (as given by the Schwarzschild radius of about 32 km) in roughly 2.7 Myr. This result has dramatic implications on the evolution and lifetime of black hole X-ray binaries. [ABSTRACT FROM AUTHOR]
Published: 2017
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241. Doppler tomography of XTE J1118+480 revealing chromospheric emission from the secondary star.

Author: Zurita, C., Hernández, J. I. González, Escorza, A., and Casares, J.
Subjects: *SOLAR chromosphere, *X-ray binaries, *ACCRETION disks, *BINARY black holes, *CENTROID
Abstract: Doppler tomography of emission lines in low-mass X-ray binaries allows us to investigate the structure and variability of the accretion disks as well as possible activity arising from the secondary stars. We present Doppler maps of the black hole binary XTE J1118+480 from spectra obtained using OSIRIS@GTC during quiescence on four different nights in 2011 and 2012. Doppler imaging of the Hα line shows, for the first time, a narrow component from the secondary star with observed equivalent widths varying in the range 1.2-2.9 Å but not correlated with the veiling of the accretion disc. The Hα flux of the secondary star is too large to be powered by X-ray irradiation, supporting chromospheric activity, possibly induced by rapid rotation, as the most likely origin of this feature in the black hole X-ray binary XTE J1118+480. In addition, we detect variations in the centroid of the Hα line on nightly basis. These are likely caused by a precessing accretion disc, although with a much lower amplitude (?~50 km/s-1) than previously observed. [ABSTRACT FROM AUTHOR]
Published: 2016
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242. Supernova 2014J at M82 - II. Direct analysis of a middle-class Type Ia supernova.

Author: Vallely, Patrick, Moreno-Raya, M. E., Baron, E., Ruiz-Lapuente, Pilar, Domínguez, I., Galbany, Lluís, Hernández, J. I. González, Méndez, J., Hamuy, M., López-Sánchez, A. R., Catalán, S., Cooke, E., Fariña, C., Génova-Santos, R., Karjalainen, R., Lietzen, H., McCormac, J., Riddick, F., Rubiño-Martín, J. A., and Skillen, I.
Subjects: SUPERNOVAE, OPTICAL spectra, SPECTROSCOPIC imaging, OXYGEN compounds, STELLAR evolution
Abstract: We analyse a time series of optical spectra of SN 2014J from almost two weeks prior to maximum to nearly four months after maximum. We perform our analysis using the SYNOW code, which is well suited to track the distribution of the ions with velocity in the ejecta. We show that almost all of the spectral features during the entire epoch can be identified with permitted transitions of the common ions found in normal supernovae (SNe) Ia in agreement with previous studies. We show that 2014J is a relatively normal SN Ia. At early times the spectral features are dominated by Si II, S II, Mg II, and Ca II. These ions persist to maximum light with the appearance of Na I and Mg I. At later times iron-group elements also appear, as expected in the stratified abundance model of the formation of normal Type Ia SNe. We do not find significant spectroscopic evidence for oxygen, until 100 d after maximum light. The +100 d identification of oxygen is tentative, and would imply significant mixing of unburned or only slight processed elements down to a velocity of 6000 kms-1. Our results are in relatively good agreement with other analyses in the infrared. We briefly compare SN 2011fe to SN 2014J and conclude that the differences could be due to different central densities at ignition or differences in the C/O ratio of the progenitors. [ABSTRACT FROM AUTHOR]
Published: 2016
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243. EChO

Author: Tinetti, G., primary, Beaulieu, J. P., additional, Henning, T., additional, Meyer, M., additional, Micela, G., additional, Ribas, I., additional, Stam, D., additional, Swain, M., additional, Krause, O., additional, Ollivier, M., additional, Pace, E., additional, Swinyard, B., additional, Aylward, A., additional, van Boekel, R., additional, Coradini, A., additional, Encrenaz, T., additional, Snellen, I., additional, Zapatero-Osorio, M. R., additional, Bouwman, J., additional, Cho, J. Y-K., additional, Coudé de Foresto, V., additional, Guillot, T., additional, Lopez-Morales, M., additional, Mueller-Wodarg, I., additional, Palle, E., additional, Selsis, F., additional, Sozzetti, A., additional, Ade, P. A. R., additional, Achilleos, N., additional, Adriani, A., additional, Agnor, C. B., additional, Afonso, C., additional, Prieto, C. Allende, additional, Bakos, G., additional, Barber, R. J., additional, Barlow, M., additional, Batista, V., additional, Bernath, P., additional, Bézard, B., additional, Bordé, P., additional, Brown, L. R., additional, Cassan, A., additional, Cavarroc, C., additional, Ciaravella, A., additional, Cockell, C., additional, Coustenis, A., additional, Danielski, C., additional, Decin, L., additional, Kok, R. De, additional, Demangeon, O., additional, Deroo, P., additional, Doel, P., additional, Drossart, P., additional, Fletcher, L. N., additional, Focardi, M., additional, Forget, F., additional, Fossey, S., additional, Fouqué, P., additional, Frith, J., additional, Galand, M., additional, Gaulme, P., additional, Hernández, J. I. González, additional, Grasset, O., additional, Grassi, D., additional, Grenfell, J. L., additional, Griffin, M. J., additional, Griffith, C. A., additional, Grözinger, U., additional, Guedel, M., additional, Guio, P., additional, Hainaut, O., additional, Hargreaves, R., additional, Hauschildt, P. H., additional, Heng, K., additional, Heyrovsky, D., additional, Hueso, R., additional, Irwin, P., additional, Kaltenegger, L., additional, Kervella, P., additional, Kipping, D., additional, Koskinen, T. T., additional, Kovács, G., additional, La Barbera, A., additional, Lammer, H., additional, Lellouch, E., additional, Leto, G., additional, Lopez Morales, M., additional, Lopez Valverde, M. A., additional, Lopez-Puertas, M., additional, Lovis, C., additional, Maggio, A., additional, Maillard, J. P., additional, Maldonado Prado, J., additional, Marquette, J. B., additional, Martin-Torres, F. J., additional, Maxted, P., additional, Miller, S., additional, Molinari, S., additional, Montes, D., additional, Moro-Martin, A., additional, Moses, J. I., additional, Mousis, O., additional, Nguyen Tuong, N., additional, Nelson, R., additional, Orton, G. S., additional, Pantin, E., additional, Pascale, E., additional, Pezzuto, S., additional, Pinfield, D., additional, Poretti, E., additional, Prinja, R., additional, Prisinzano, L., additional, Rees, J. M., additional, Reiners, A., additional, Samuel, B., additional, Sánchez-Lavega, A., additional, Forcada, J. Sanz, additional, Sasselov, D., additional, Savini, G., additional, Sicardy, B., additional, Smith, A., additional, Stixrude, L., additional, Strazzulla, G., additional, Tennyson, J., additional, Tessenyi, M., additional, Vasisht, G., additional, Vinatier, S., additional, Viti, S., additional, Waldmann, I., additional, White, G. J., additional, Widemann, T., additional, Wordsworth, R., additional, Yelle, R., additional, Yung, Y., additional, and Yurchenko, S. N., additional
Published: 2012
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244. The Search for Extremely Low-Metallicity Stars in Dwarf Galaxies Using the NIR Ca II Triplet

Author: Starkenburg, E., primary, Hill, V., additional, Tolstoy, E., additional, Hernández, J. I. González, additional, Irwin, M., additional, Helmi, A., additional, Boschman, L., additional, Francois, P., additional, Battaglia, G., additional, Jablonka, P., additional, Tafelmeyer, M., additional, Shetrone, M., additional, Venn, K., additional, and de Boer, T., additional
Published: 2011
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245. Erratum: A search for interstellar anthracene toward the Perseus anomalous microwave emission region

Author: Iglesias-Groth, S., primary, Manchado, A., additional, Rebolo, R., additional, Hernández, J. I. González, additional, García-Hernández, D. A., additional, and Lambert, D. L., additional
Published: 2010
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246. SEARCHING FOR THE SIGNATURES OF TERRESTRIAL PLANETS IN SOLAR ANALOGS

Author: Hernández, J. I. González, primary, Israelian, G., additional, Santos, N. C., additional, Sousa, S., additional, Delgado-Mena, E., additional, Neves, V., additional, and Udry, S., additional
Published: 2010
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247. On the mass of the neutron star in Cyg X-2

Author: Casares, J., primary, Hernández, J. I. González, additional, Israelian, G., additional, and Rebolo, R., additional
Published: 2010
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248. THE CHEMICAL COMPOSITION OF CERNIS 52 (BD+31° 640)

Author: Hernández, J. I. González, primary, Iglesias-Groth, S., additional, Rebolo, R., additional, García-Hernández, D. A., additional, Manchado, A., additional, and Lambert, D. L., additional
Published: 2009
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249. CS 22876–032: The Most Metal‐Poor Dwarfs. Abundances and 3D Effects

Author: Hernández, J. I. González, primary, Bonifacio, P., additional, Ludwig, H.‐G., additional, Caffau, E., additional, Spite, M., additional, Spite, F., additional, Cayrel, R., additional, Molaro, P., additional, Hill, V., additional, François, P., additional, Plez, B., additional, Beers, T. C., additional, Sivarani, T., additional, Andersen, J., additional, Barbuy, B., additional, Depagne, E., additional, Nordström, B., additional, and Primas, F., additional
Published: 2008
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250. The Metal‐Poor End of the Lithium Plateau

Author: Sbordone, L., primary, Bonifacio, P., additional, Hernández, J. I. González, additional, Cayrel, R., additional, Behara, N., additional, Molaro, P., additional, Plez, B., additional, Francois, P., additional, Christlieb, N., additional, Ludwig, H.‐G., additional, Sivarani, T., additional, Beers, T. C., additional, and Van't Veer, C., additional
Published: 2008
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