149 research outputs found

    Análisis de la fertilidad potencial del canino (Canis Lupus Familiaris) posterior a la inyección intratesticular de Cloruro de Calcio al 20%

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    Una de las principales técnicas utilizadas para el control de la población canina es la castración. La técnica quirúrgica sin lugar a dudas es la más utilizada y conocida, sin embargo la opción de la castración química ha ido tomando fuerza como una alternativa a la castración quirúrgica, debido a que se considera un proceso no invasivo, económico y de fácil realización, sobre todo en casos de castración masiva de animales como control de la población callejera. En este estudio se utilizó un total de 20 caninos, los cuales se dividieron en: grupos experimentales (1, 2, 3) y grupo control. A los tres grupos experimentales se les aplicó una inyección por vía intratesticular de cloruro de calcio al 20% en ambos testículos, mientras que, al grupo control se le inyectó por la misma vía, solución fisiológica al 0,9%. Previo a esta inoculación todos los pacientes fueron sometidos a un examen físico general, examen andrológico, análisis de fertilidad mediante espermiograma y análisis plasmático de testosterona mediante radio inmuno ensayo (RIA). Al grupo experimental 1 y al grupo control, luego de 7 días post inoculación, se les realizó un nuevo análisis de fertilidad mediante espermiograma y análisis plasmático de testosterona. En el caso del grupo experimental 2 el procedimiento anterior se realizó después de 14 días de la inoculación y el grupo experimental 3, después de 21 días. En relación con el análisis espermático, el grupo experimental 1 no presentó diferencias significativas en ningún parámetro analizado. El grupo experimental 2 presentó diferencias estadísticamente significativas en volumen, concentración espermática y motilidad progresiva. El grupo experimental 3 presentó diferencias estadísticamente significativas en el volumen entre el tiempo inicial y a los 21 días posterior a la inoculación, los parámetros restantes del espermiograma no fueron analizados puesto que no se obtuvo líquido seminal en los pacientes de este grupo, indicando que a los 21 días existiría daño en el tejido testicular evidenciado por la ausencia de espermatogénesis. Los resultados del análisis plasmático de testosterona indicaron que solo en el grupo experimental 3 la concentración de ésta hormona presentó una disminución estadísticamente significativa, por lo cual a partir de los 21 días post-inoculación la concentración de esta hormona comenzaría a descender. Debido a los resultados obtenidos podemos concluir que la utilización de cloruro de calcio al 20% vía intratesticular es una técnica eficaz en lograr la castración, lo que se manifiesta con mayor seguridad a partir de los 21 días post inyección, fácil de realizar y sin efectos adversos, lo que la hace una opción válida, sobre todo en planes de esterilización masiva.  

    The CARMENES search for exoplanets around M dwarfs: Two planets on opposite sides of the radius gap transiting the nearby M dwarf LTT 3780

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    Full list of authors: Nowak, G.; Luque, R.; Parviainen, H.; Pallé, E.; Molaverdikhani, K.; Béjar, V. J. S.; Lillo-Box, J.; Rodríguez-López, C.; Caballero, J. A.; Zechmeister, M.; Passegger, V. M.; Cifuentes, C.; Schweitzer, A.; Narita, N.; Cale, B.; Espinoza, N.; Murgas, F.; Hidalgo, D.; Zapatero Osorio, M. R.; Pozuelos, F. J.; Aceituno, F. J.; Amado, P. J.; Barkaoui, K.; Barrado, D.; Bauer, F. F.; Benkhaldoun, Z.; Caldwell, D. A.; Casasayas Barris, N.; Chaturvedi, P.; Chen, G.; Collins, K. A.; Collins, K. I.; Cortés-Contreras, M.; Crossfield, I. J. M.; de León, J. P.; Díez Alonso, E.; Dreizler, S.; El Mufti, M.; Esparza-Borges, E.; Essack, Z.; Fukui, A.; Gaidos, E.; Gillon, M.; Gonzales, E. J.; Guerra, P.; Hatzes, A.; Henning, Th.; Herrero, E.; Hesse, K.; Hirano, T.; Howell, S. B.; Jeffers, S. V.; Jehin, E.; Jenkins, J. M.; Kaminski, A.; Kemmer, J.; Kielkopf, J. F.; Kossakowski, D.; Kotani, T.; Kürster, M.; Lafarga, M.; Latham, D. W.; Law, N.; Lissauer, J. J.; Lodieu, N.; Madrigal-Aguado, A.; Mann, A. W.; Massey, B.; Matson, R. A.; Matthews, E.; Montañés-Rodríguez, P.; Montes, D.; Morales, J. C.; Mori, M.; Nagel, E.; Oshagh, M.; Pedraz, S.; Plavchan, P.; Pollacco, D.; Quirrenbach, A.; Reffert, S.; Reiners, A.; Ribas, I.; Ricker, G. R.; Rose, M. E.; Schlecker, M.; Schlieder, J. E.; Seager, S.; Stangret, M.; Stock, S.; Tamura, M.; Tanner, A.; Teske, J.; Trifonov, T.; Twicken, J. D.; Vanderspek, R.; Watanabe, D.; Wittrock, J.; Ziegler, C.; Zohrabi, F.We present the discovery and characterisation of two transiting planets observed by the Transiting Exoplanet Survey Satellite (TESS) orbiting the nearby (d∗ ≈ 22 pc), bright (J ≈ 9 mag) M3.5 dwarf LTT 3780 (TOI-732). We confirm both planets and their association with LTT 3780 via ground-based photometry and determine their masses using precise radial velocities measured with the CARMENES spectrograph. Precise stellar parameters determined from CARMENES high-resolution spectra confirm that LTT 3780 is a mid-M dwarf with an effective temperature of Teff = 3360 ± 51 K, a surface gravity of log g∗ = 4.81 ± 0.04 (cgs), and an iron abundance of [Fe/H] = 0.09 ± 0.16 dex, with an inferred mass of M∗ = 0.379 ± 0.016M· and a radius of R∗ = 0.382 ± 0.012R·. The ultra-short-period planet LTT 3780 b (Pb = 0.77 d) with a radius of 1.35-0.06+0.06 R·, a mass of 2.34-0.23+0.24 M·, and a bulk density of 5.24-0.81+0.94 g cm-3 joins the population of Earth-size planets with rocky, terrestrial composition. The outer planet, LTT 3780 c, with an orbital period of 12.25 d, radius of 2.42-0.10+0.10 R·, mass of 6.29-0.61+0.63 M·, and mean density of 2.45-0.37+0.44 g cm-3 belongs to the population of dense sub-Neptunes. With the two planets located on opposite sides of the radius gap, this planetary system is anexcellent target for testing planetary formation, evolution, and atmospheric models. In particular, LTT 3780 c is an ideal object for atmospheric studies with the James Webb Space Telescope (JWST). © 2020 ESO.CARMENES is an instrument for the Centro Astronomico Hispano-Aleman de Calar Alto (CAHA, Almeria, Spain). CARMENES is funded by the German Max-Planck-Gesellschaft (MPG), the Spanish Consejo Superior de Investigaciones Cientificas (CSIC), the European Union through FEDER/ERF FICTS-2011-02 funds, and the members of the CARMENES Consortium (Max-Planck-Institut fur Astronomie, Instituto de Astrofisica de Andalucia, Landessternwarte Konigstuhl, Institut de Ciencies de l'Espai, Institut fur Astrophysik Gottingen, Universidad Complutense de Madrid, Thuringer Landessternwarte Tautenburg, Instituto de Astrofisica de Canarias, Hamburger Sternwarte, Centro de Astrobiologia and Centro Astronomico Hispano-Aleman), with additional contributions by the Spanish Ministry of Economy, the German Science Foundation through the Major Research Instrumentation Programme and DFG Research Unit FOR2544 "Blue Planets around Red Stars", the Klaus Tschira Stiftung, the states of Baden-Wurttemberg and Niedersachsen, and by the Junta de Andalucia. This paper includes data collected by the TESS mission. Funding for the TESS mission is provided by the NASA Explorer Program. We acknowledge the use of public TOI Release data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. This research has made use of the Exoplanet Follow-up Observation Program website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https://www.cosmos.esa.int/web/gaia/dpac/consortium).Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This article is partly based on observations made with the MuSCAT2 instrument, developed by ABC, at Telescopio Carlos Sanchez operated on the island of Tenerife by the IAC in the Spanish Observatorio del Teide. This work makes use of observations from the LCOGT network. This work makes use of observations acquired with the T150 telescope at Sierra Nevada Observatory, operated by the Instituto de Astrofisica de Andalucia (IAACSIC). Some of the Observations in the paper made use of the High-Resolution Imaging instrument 'Alopeke at Gemini-North. `Alopeke was funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by Steve B. Howell, Nic Scott, Elliott P. Horch, and Emmett Quigley. IRD is operated by the Astrobiology Center of the National Institutes of Natural Sciences. The research leading to these results has received funding from the ARC grant for Concerted Research Actions, financed by the WalloniaBrussels Federation. TRAPPIST is funded by the Belgian Fund for Scientific Research (Fond National de la Recherche Scientifique, FNRS) under the grant FRFC 2.5.594.09.F, with the participation of the Swiss National Science Fundation (SNF). TRAPPIST-North is a project funded by the University of Liege (Belgium), in collaboration with Cadi Ayyad University of Marrakech (Morocco) M.G. and E.J. are F.R.S.-FNRS Senior Research Associate. The authors acknowledge funding from the Spanish Ministry of Economics and Competitiveness through projects PGC2018-098153-B-C31 and AYA2015-69350-C3-2-P. This work is partly supported by JSPS KAKENHI Grant Numbers JP18H01265 and JP18H05439, and JST PRESTO Grant Number JPMJPR1775. V.M.P. acknowledges support from NASA Grant NNX17AG24G. T.H. acknowledges support from the European Research Council under the Horizon 2020 Framework Program via the ERC Advanced Grant Origins 83 24 28. This research has been partially funded by Project No. MDM-2017-0737 Unidad de Excelencia "Maria de Maeztu" -Centro de Astrobiologia (INTA-CSIC). This research acknowledges financial support from the State Agency for Research of the Spanish MCIU through the "Center of Excellence Severo Ochoa" award to the Instituto de Astrofisica de Andalucia (SEV-2017-0709) and project AYA2016-794425

    TOI-1201 b: A mini-Neptune transiting a bright and moderately young M dwarf

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    Kossakowski, D., et al.We present the discovery of a transiting mini-Neptune around TOI-1201, a relatively bright and moderately young early M dwarf (J ≈ 9.5 mag, ~600-800 Myr) in an equal-mass ~8 arcsecond-wide binary system, using data from the Transiting Exoplanet Survey Satellite, along with follow-up transit observations. With an orbital period of 2.49 d, TOI-1201 b is a warm mini-Neptune with a radius of Rb = 2.415 ± 0.090 R⊕. This signal is also present in the precise radial velocity measurements from CARMENES, confirming the existence of the planet and providing a planetary mass of Mb = 6.28 ± 0.88 M⊕ and, thus, an estimated bulk density of 2.45-0.42+0.48 g cm-3. The spectroscopic observations additionally show evidence of a signal with a period of 19 d and a long periodic variation of undetermined origin. In combination with ground-based photometric monitoring from WASP-South and ASAS-SN, we attribute the 19 d signal to the stellar rotation period (Prot = 19-23 d), although we cannot rule out that the variation seen in photometry belongs to the visually close binary companion. We calculate precise stellar parameters for both TOI-1201 and its companion. The transiting planet is anexcellent target for atmosphere characterization (the transmission spectroscopy metric is 97-16+21) with the upcoming James Webb Space Telescope. It is also feasible to measure its spin-orbit alignment via the Rossiter-McLaughlin effect using current state-of-the-art spectrographs with submeter per second radial velocity precision.Part of this work was supported by the German Deutsche Forschungsgemeinschaft (DFG) project number Ts 17/2–1. CARMENES is an instrument at the Centro Astronómico Hispano-Alemán (CAHA) at Calar Alto (Almería, Spain), operated jointly by the Junta de Andalucía and the Instituto de Astrofísica de Andalucía (CSIC). CARMENES was funded by the Max-Planck-Gesellschaft (MPG), the Consejo Superior de Investigaciones Científicas (CSIC), the Ministerio de Economía y Competitividad (MINECO) and the European Regional Development Fund (ERDF) through projects FICTS-2011-02, ICTS-2017-07-CAHA-4, and CAHA16-CE-3978, and the members of the CARMENES Consortium (Max-Planck-Institut für Astronomie, Instituto de Astrofísica de Andalucía, Landessternwarte Königstuhl, Institut de Ciències de l’Espai, Institut für Astrophysik Göttingen, Universidad Complutense de Madrid, Thüringer Landessternwarte Tautenburg,Instituto de Astrofísica de Canarias, Hamburger Sternwarte, Centro de Astrobiología and Centro Astronómico Hispano-Alemán), with additional contributions by the MINECO, the Deutsche Forschungsgemeinschaft through the Major Research Instrumentation Programme and Research Unit FOR2544 “Blue Planets around Red Stars”, the Klaus Tschira Stiftung, the states of Baden-Württemberg and Niedersachsen, and by the Junta de Andalucía. This work was based on data from the CARMENES data archive at CAB (CSIC-INTA). We acknowledgefinancial support from the Agencia Estatal de Investigación of the Ministerio de Ciencia, Innovación y Universidades and the ERDF through projects PID2019-109522GB-C5[1:4]/AEI/10.13039/501100011033 and the Centre of Excellence “Severo Ochoa” and “María de Maeztu” awards to the Instituto de Astrofísica de Canarias (SEV-2015-0548), Instituto de Astrofísica de Andalucía (SEV-2017-0709), and Centro de Astrobiología (MDM-2017-0737), the European Research Council under the Horizon 2020 Framework Program (ERC Advanced Grant Origins 83 24 28), the Generalitat de Catalunya/CERCA programme, the DFG priority program SPP 1992 “Exploring the Diversity of Extrasolar Planets (JE 701/5-1)”, the European Research Council under the Horizon 2020 Framework Program via ERC Advanced Grant Origins 832428 and under Marie Skłodowska-Curie grant 895525

    TOI-1468: A system of two transiting planets, a super-Earth and a mini-Neptune, on opposite sides of the radius valley

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    Full list of authors: Chaturvedi, P.; Bluhm, P.; Nagel, E.; Hatzes, A. P.; Morello, G.; Brady, M.; Korth, J.; Molaverdikhani, K.; Kossakowski, D.; Caballero, J. A.; Guenther, E. W.; Palle, E.; Espinoza, N.; Seifahrt, A.; Lodieu, N.; Cifuentes, C.; Furlan, E.; Amado, P. J.; Barclay, T.; Bean, J.; Bejar, V. J. S.; Bergond, G.; Boyle, A. W.; Ciardi, D.; Collins, K. A.; Collins, K., I; Esparza-Borges, E.; Fukui, A.; Gnilka, C. L.; Goeke, R.; Guerra, P.; Henning, Th; Herrero, E.; Howell, S. B.; Jeffers, S., V; Jenkins, J. M.; Jensen, E. L. N.; Kasper, D.; Kodama, T.; Latham, D. W.; Lopez-Gonzalez, M. J.; Luque, R.; Montes, D.; Morales, J. C.; Mori, M.; Murgas, F.; Narita, N.; Nowak, G.; Parviainen, H.; Passegger, V. M.; Quirrenbach, A.; Reffert, S.; Reiners, A.; Ribas, I; Ricker, G. R.; Rodriguez, E.; Rodriguez-Lopez, C.; Schlecker, M.; Schwarz, R. P.; Schweitzer, A.; Seager, S.; Stefansson, G.; Stockdale, C.; Tal-Or, L.; Twicken, J. D.; Vanaverbeke, S.; Wang, G.; Watanabe, D.; Winn, J. N.; Zechmeister, M.--This is an Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.We report the discovery and characterization of two small transiting planets orbiting the bright M3.0V star TOI-1468 (LSPM J0106+1913), whose transit signals were detected in the photometric time series in three sectors of the TESS mission. We confirm the planetary nature of both of them using precise radial velocity measurements from the CARMENES and MAROON-X spectrographs, and supplement them with ground-based transit photometry. A joint analysis of all these data reveals that the shorter-period planet, TOI-1468 b (Pb = 1.88 d), has a planetary mass of Mb = 3.21 ± 0.24M⊕ and a radius of Rb = 1.280−0.039+0.038 R⊕, resulting in a density of ρb = 8.39−0.92+1.05 g cm−3, which is consistent with a mostly rocky composition. For the outer planet, TOI-1468 c (Pc = 15.53 d), we derive a mass of Mc = 6.64−0.68+0.67 M⊕,aradius of Rc = 2.06 ± 0.04 R⊕, and a bulk density of ρc = 2.00−0.19+0.21 g cm−3, which corresponds to a rocky core composition with a H/He gas envelope. These planets are located on opposite sides of the radius valley, making our system an interesting discovery as there are only a handful of other systems with the same properties. This discovery can further help determine a more precise location of the radius valley for small planets around M dwarfs and, therefore, shed more light on planet formation and evolution scenarios. © P. Chaturvedi et al. 2022.CARMENES is an instrument at the Centro Astronómico Hispano en Andalucía (CAHA) at Calar Alto (Almería, Spain), operated jointly by the Junta de Andalucía and the Instituto de Astrofísica de Andalucía (CSIC). CARMENES was funded by the Max-Planck-Gesellschaft (MPG), the Consejo Superior de Investigaciones Científicas (CSIC), the Ministerio de Economía y Competitividad (MINECO) and the European Regional Development Fund (ERDF) through projects FICTS-2011-02, ICTS-2017-07-CAHA-4, and CAHA16-CE-3978, and the members of the CARMENES Consortium (Max-Planck-Institut für Astronomie, Instituto de Astrofísica de Andalucía, Landessternwarte Königstuhl, Institut de Ciències de l’Espai, Institut für Astrophysik Göttingen, Universidad Complutense de Madrid, Thüringer Landessternwarte Tautenburg, Instituto de Astrofísica de Canarias, Hamburger Sternwarte, Centro de Astrobiología and Centro Astronómico Hispano-Alemán), with additional contributions by the MINECO, the Deutsche Forschungsgemeinschaft (DFG) through the Major Research Instrumentation Programme and Research Unit FOR2544 “Blue Planets around Red Stars”, the Klaus Tschira Stiftung, the states of Baden-Württemberg and Niedersachsen, and by the Junta de Andalucía. This work was based on data from the CARMENES data archive at CAB (CSIC-INTA). Funding for the TESS mission is provided by NASA’s Science Mission Directorate. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center. This research has made use of the Exoplanet Follow-up Observation Program website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exo-planet Exploration Program. Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. This paper includes data collected by the TESS mission that are publicly available from the Mikulski Archive for Space Telescopes (MAST). The development of the MAROON-X spectrograph was funded by the David and Lucile Packard Foundation, the Heising-Simons Foundation, the Gemini Observatory, and the University of Chicago. The MAROON-X team acknowledges support for this work from the NSF (award number 2108465) and NASA (through the TESS Cycle 4 GI program, grant number 80NSSC22K0117). This work was enabled by observations made from the Gemini North telescope, located within the Maunakea Science Reserve and adjacent to the summit of Maunakea. We are grateful for the privilege of observing the Universe from a place that is unique in both its astronomical quality and its cultural significance. Data were partly collected with the 150-cm telescope at Observatorio de Sierra Nevada (OSN), operated by the Instituto de Astrofífica de Andalucía (IAA, CSIC), with the MuSCAT2 instrument, developed by ABC, at Telescopio Carlos Sánchez operated on the island of Tenerife by the IAC in the Spanish Observatorio del Teide, with the Telescopi Joan Oró (TJO) of the Observatori Astronómic del Montsed (OdM), which is owned by the Generalitat de Catalunya and operated by the Institute for Space Studies of Catalonia (IEEC), and with the LCOFT network (part of the LCOGT telescope time was granted by NOIRLab through the Mid-Scale Innovations Program (MSIP), which is funded by the National Science Foundation). Some of the Observations in the paper made use of the High-Resolution Imaging instrument. ‘Alopeke. ‘Alopeke was funded by the NASA Exoplanet Exploration Program and built at the NASA Ames Research Center by Steve B. Howell, Nic Scott, Elliott P. Horch, and Emmett Quigley. Data were reduced using a software pipeline originally written by Elliott Horch and Mark Everett. ‘Alopeke was mounted on the Gemini North telescope of the international Gemini Observatory, a program of NSF s OIR Lab, which is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation. on behalf of the Gemini partnership: the National Science Foundation (United States), National Research Council (Canada), Agencia Nacional de Investigación y Desarrollo (Chile), Ministerio de Ciencia, Tecnología e Innovación (Argentina), Ministério da Ciência, Tecnologia, Inovações e Comunicações (Brazil), and Korea Astronomy and Space Science Institute (Republic of Korea). We acknowledge financial support from: the Thüringer Ministerium für Wirtschaft, Wissenschaft und Digitale Gesellschaft; the Spanish Agencia Estatal de Investigación of the Ministerio de Ciencia e Innovación and the ERDF “A way of making Europe” through projects PID2019-109522GB-C5[1:4], PID2019-107061GB-C64, PID2019-110689RB-100, PGC2018-098153-B-C31, and the Centre of Excellence “Severo Ochoa” and “María de Maeztu” awards to the Instituto de Astrofísica de Canarias (CEX2019-000920-S), Instituto de Astrofísica de Andalucía (SEV-2017-0709), and Centro de Astrobiología (MDM-2017-0737); the Generalitat de Catalunya/CERCA programme; the European Union s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 895525; the DFG through grant CH 2636/1-1, the Excellence Cluster ORIGINS under Germany’s Excellence Strategy (EXC-2094 – 390783311), and priority programme SPP 1992 “Exploring the Diversity of Extrasolar Planets” (JE 701/5-1); the Swedish National Space Agency (SNSA; DNR 2020-00104); the JSPS KAKENHI grants JP17H04574, JP18H05439, JP21K13975, Grant-in-Aid for JSPS fellows grant JP20J21872, JST CREST Grant Number JPMJCR1761, and the Astrobiology Center of National Institutes of Natural Sciences (NINS) through grants AB031010 and AB031014; and the program “Alien Earths” (supported by the National Aeronautics and Space Administration under agreement No. 80NSSC21K0593) for NASA’s Nexus for Exoplanet System Science (NExSS) research coordination network sponsored by NASA’s Science Mission Directorate.Peer reviewe

    The CARMENES search for exoplanets around M dwarfs: Convective shift and starspot constraints from chromatic radial velocities

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    Context. Variability caused by stellar activity represents a challenge to the discovery and characterization of terrestrial exoplanets and complicates the interpretation of atmospheric planetary signals. Aims. We aim to use a detailed modeling tool to reproduce the effect of active regions on radial velocity measurements, which aids the identification of the key parameters that have an impact on the induced variability. Methods. We analyzed the effect of stellar activity on radial velocities as a function of wavelength by simulating the impact of the properties of spots, shifts induced by convective motions, and rotation. We focused our modeling effort on the active star YZ CMi (GJ 285), which was photometrically and spectroscopically monitored with CARMENES and the Telescopi Joan Or\'o. Results. We demonstrate that radial velocity curves at different wavelengths yield determinations of key properties of active regions, including spot filling factor, temperature contrast, and location, thus solving the degeneracy between them. Most notably, our model is also sensitive to convective motions. Results indicate a reduced convective shift for M dwarfs when compared to solar-type stars (in agreement with theoretical extrapolations) and points to a small global convective redshift instead of blueshift. Conclusions. Using a novel approach based on simultaneous chromatic radial velocities and light curves, we can set strong constraints on stellar activity, including an elusive parameter such as the net convective motion effect.Comment: A&A, in pres

    The CARMENES search for exoplanets around M dwarfs. A sub-Neptunian mass planet in the habitable zone of HN Lib

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    We report the discovery of HN Lib b, a sub-Neptunian mass planet orbiting the nearby (dd \approx = 6.25 pc) M4.0 V star HN Lib detected by our CARMENES radial-velocity (RV) survey. We determined a planetary minimum mass of Mbsini=M_\text{b}\sin i = 5.46 ±\pm 0.75 M\text{M}_\oplus and an orbital period of Pb=P_\text{b} = 36.116 ±\pm 0.029 d, using \sim5 yr of CARMENES data, as well as archival RVs from HARPS and HIRES spanning more than 13 years. The flux received by the planet equals half the instellation on Earth, which places it in the middle of the conservative habitable zone (HZ) of its host star. The RV data show evidence for another planet candidate with M[c]sini=M_\text{[c]}\sin i = 9.7 ±\pm 1.9 M\text{M}_\oplus and P[c]=P_\text{[c]} = 113.46 ±\pm 0.20 d. The long-term stability of the signal and the fact that the best model for our data is a two-planet model with an independent activity component stand as strong arguments for establishing a planetary origin. However, we cannot rule out stellar activity due to its proximity to the rotation period of HN Lib, which we measured using CARMENES activity indicators and photometric data from a ground-based multi-site campaign as well as archival data. The discovery adds HN Lib b to the shortlist of super-Earth planets in the habitable zone of M dwarfs, but HN Lib [c] probably cannot be inhabited because, if confirmed, it would most likely be an icy giant

    TOI-1801 b: A temperate mini-Neptune around a young M0.5 dwarf

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    Mallorquín, M., et al.We report the discovery, mass, and radius determination of TOI-1801 b, a temperate mini-Neptune around a young M dwarf. TOI-1801 b was observed in TESS sectors 22 and 49, and the alert that this was a TESS planet candidate with a period of 21.3 days went out in April 2020. However, ground-based follow-up observations, including seeing-limited photometry in and outside transit together with precise radial velocity (RV) measurements with CARMENES and HIRES revealed that the true period of the planet is 10.6 days. These observations also allowed us to retrieve a mass of 5.74 ± 1.46 M⊕, which together with a radius of 2.08 ± 0.12 R⊕, means that TOI-1801 b is most probably composed of water and rock, with an upper limit of 2% by mass of H2 in its atmosphere. The stellar rotation period of 16 days is readily detectable in our RV time series and in the ground-based photometry. We derived a likely age of 600–800 Myr for the parent star TOI-1801, which means that TOI-1801 b is the least massive young mini-Neptune with precise mass and radius determinations. Our results suggest that if TOI-1801 b had a larger atmosphere in the past, it must have been removed by some evolutionary mechanism on timescales shorter than 1 Gyr.This work is partly financed by the Spanish Ministry of Economics and Competitiveness through projects PGC2018-098153-B-C31, PID2019-109522GB-C5[1:4]. E. G. acknowledges the generous support from the Deutsche Forschungsgemeinschaft (DFG) of the grant HA3279/14-1. P.D. acknowledges support from a 51 Pegasi b Postdoctoral Fellowship from the Heising-Simons Foundation. D.H. acknowledges support from the Alfred P. Sloan Foundation, the National Aeronautics and Space Administration (80NSSC21K0652) and the Australian Research Council (FT200100871). This work is partly supported by JSPS KAKENHI Grant Numbers JP18H05439 and JST CREST Grant Number JPMJCR176.Peer reviewe

    Discovery and mass measurement of the hot, transiting, Earth-sized planet, GJ 3929 b

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    Full list of authors: Kemmer, J.; Dreizler, S.; Kossakowski, D.; Stock, S.; Quirrenbach, A.; Caballero, J. A.; Amado, P. J.; Collins, K. A.; Espinoza, N.; Herrero, E.; Jenkins, J. M.; Latham, D. W.; Lillo-Box, J.; Narita, N.; Pallé, E.; Reiners, A.; Ribas, I.; Ricker, G.; Rodríguez, E.; Seager, S.; Vanderspek, R.; Wells, R.; Winn, J.; Aceituno, F. J.; Béjar, V. J. S.; Barclay, T.; Bluhm, P.; Chaturvedi, P.; Cifuentes, C.; Collins, K. I.; Cortés-Contreras, M.; Demory, B. -O.; Fausnaugh, M. M.; Fukui, A.; Gómez Maqueo Chew, Y.; Galadí-Enríquez, D.; Gan, T.; Gillon, M.; Golovin, A.; Hatzes, A. P.; Henning, Th.; Huang, C.; Jeffers, S. V.; Kaminski, A.; Kunimoto, M.; Kürster, M.; López-González, M. J.; Lafarga, M.; Luque, R.; McCormac, J.; Molaverdikhani, K.; Montes, D.; Morales, J. C.; Passegger, V. M.; Reffert, S.; Sabin, L.; Schöfer, P.; Schanche, N.; Schlecker, M.; Schroffenegger, U.; Schwarz, R. P.; Schweitzer, A.; Sota, A.; Tenenbaum, P.; Trifonov, T.; Vanaverbeke, S.; Zechmeister, M.We report the discovery of GJ 3929 b, a hot Earth-sized planet orbiting the nearby M3.5 V dwarf star, GJ 3929 (G 180-18, TOI-2013). Joint modelling of photometric observations from TESS sectors 24 and 25 together with 73 spectroscopic observations from CARMENES and follow-up transit observations from SAINT-EX, LCOGT, and OSN yields a planet radius of Rb = 1.150 ± 0.040 R⊕, a mass of Mb = 1.21 ± 0.42 M⊕, and an orbital period of Pb = 2.6162745 ± 0.0000030 d. The resulting density of ρb = 4.4 ± 1.6 g cm−3 is compatible with the Earth’s mean density of about 5.5 g cm−3. Due to the apparent brightness of the host star (J = 8.7 mag) and its small size, GJ 3929 b is a promising target for atmospheric characterisation with the JWST. Additionally, the radial velocity data show evidence for another planet candidate with P[c] = 14.303 ± 0.035 d, which is likely unrelated to the stellar rotation period, Prot = 122 ± 13 d, which we determined from archival HATNet and ASAS-SN photometry combined with newly obtained TJO data. © ESO 2022.This paper is based on observations made with the MuSCAT3 instrument, developed by the Astrobiology Center and under financial supports by JSPS KAKENHI (JP18H05439) and JST PRESTO (JPMJPR1775), at Faulkes Telescope North on Maui, HI, operated by the Las Cumbres Observatory. This work includes observationscarried out at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir (OAN-SPM), Baja California, México. We acknowledge financial support from the Agencia Estatal de Investigación of the Ministerio de Ciencia, Innovación y Universidades and the ERDF through projects PID2019-109522GB-C5[1:4], PID2019-107061GB-C64, PID2019-110689RB-100, ESP2017-87676-C5-1-R, and the Centre of Excellence “Severo Ochoa” and “María de Maeztu” awards to the Instituto de Astrofísica de Canarias (CEX2019-000920-S), Instituto de Astrofísica de Andalucía (SEV-2017-0709), and Centro de Astrobiología (MDM-2017-0737), the Swiss National Science Foundation (PP00P2-163967 and PP00P2-190080), the Centre for Space and Habitability of the University of Bern, the National Centre for Competence in Research PlanetS, supported by the Swiss National Science Foundation, the Deutsche Forschungsgemeinschaft priority program SPP 1992 “Exploring the Diversity of Extrasolar Planets” (JE 701/5-1), the Excellence Cluster ORIGINS, which is funded by the Deutsche Forschungsgemeinschaft under Germany’s Excellence Strategy (EXC-2094 – 390783311), NASA (NNX17AG24G), JSPS KAKENHI Grant Number JP18H05439, JST CREST Grant Number JPMJCR1761, the Astrobiology Center of National Institutes of Natural Sciences (NINS) (Grant Number AB031010), the UNAM-DGAPA PAPIIT (BG-101321), the “la Caixa” Foundation (100010434), the European Union Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie (No. 847648, fellowship code LCF/BQ/PI20/11760023), and the Generalitat de Catalunya/CERCA programme. Data were partly collected with the 90-cm telescope at Observatorio de Sierra Nevada (OSN), operated by the Instituto de Astrofísica de Andalucí a (IAA, CSIC). We deeply acknowledge the OSN telescope operators for their very appreciable support.Peer reviewe

    Precise mass determination for the keystone sub-Neptune planet transiting the mid-type M dwarf G 9-40

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    Context. Despite being a prominent subset of the exoplanet population discovered in the past three decades, the nature and provenance of sub-Neptune-sized planets is still one of the open questions in exoplanet science. Aims. For planets orbiting bright stars, precisely measuring the orbital and planet parameters of the system is the best approach to distinguish between competing theories regarding their formation and evolution. Methods. We obtained 69 new radial velocity observations of the mid-M dwarf G 9-40 with the CARMENES instrument to measure for the first time the mass of its transiting sub-Neptune planet, G 9-40 b, discovered in data from the K2 mission. Results. Combined with new observations from the TESS mission during Sectors 44, 45, and 46, we are able to measure the radius of the planet to an uncertainty of 3.4% (R-b = 1.900 +/- 0.065 R-circle plus) and determine its mass with a precision of 16% (M-b = 4.00 +/- 0.63 M-circle plus). The resulting bulk density of the planet is inconsistent with a terrestrial composition and suggests the presence of either a water-rich core or a significant hydrogen-rich envelope. Conclusions. G 9-40 b is referred to as a keystone planet due to its location in period-radius space within the radius valley. Several theories offer explanations for the origin and properties of this population and this planet is a valuable target for testing the dependence of those models on stellar host mass. By virtue of its brightness and small size of the host, it joins L 98-59 d as one of the two best warm (T-eq similar to 400 K) sub-Neptunes for atmospheric characterization with JWST, which will probe cloud formation in sub-Neptune-sized planets and break the degeneracies of internal composition models
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