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1,588 results on '"European Southern Observatory"'

1. Spectroscopic follow-up of Gaia-selected white dwarfs

Author: Universitat Politècnica de Catalunya. Departament de Física, European Southern Observatory, Rebassa Mansergas, Alberto, Raddi, Roberto, Diaz Sancho, Aleix, Universitat Politècnica de Catalunya. Departament de Física, European Southern Observatory, Rebassa Mansergas, Alberto, Raddi, Roberto, and Diaz Sancho, Aleix
Abstract: Astronomy unveils the wonders of the universe, including white dwarfs. These stellar remnants, with their dense cores, offer insights into stellar evolution and the cosmos. Spectroscopy, a powerful tool in astronomy, plays a crucial role in studying their properties. By analyzing the spectra emitted by white dwarfs, astronomers can decipher their chemical composition, mass, temperature, and atmospheric conditions. This knowledge enhances our understanding of star formation, the physics of compact objects, and the fate of stars like our Sun. With advancements in telescopes and instruments like the Gaia spacecraft, the research of white dwarfs has entered a new era of discovery, opening doors to further exploration and unraveling the mysteries of these celestial objects. One effective way to contribute to this field is through this TFG, which offers information on white dwarfs and spectroscopy. The thesis includes the analysis of spectral data obtained from the European Southern Observatory, with the primary objective of reducing and calibrating the data. Furthermore, an analytical method is presented to investigate the existence of newly discovered binary systems composed of an M-dwarf and an Extremely Low Mass (ELM) white dwarf.
Published: 2023

2. SiO Outflows in the Most Luminous and Massive Protostellar Sources of the Southern Sky

Author: Max Planck Institute for Radio Astronomy, European Southern Observatory, Onsala Space Observatory (Swedish), Comisión Nacional de Investigación Científica y Tecnológica (Chile), Agencia Nacional de Investigación y Desarrollo (Chile), #NODATA#, Guerra-Varas, N., Merello, M., Bronfman, L., Duronea, N., Elia, D., Finger, R., Mendoza, E., Max Planck Institute for Radio Astronomy, European Southern Observatory, Onsala Space Observatory (Swedish), Comisión Nacional de Investigación Científica y Tecnológica (Chile), Agencia Nacional de Investigación y Desarrollo (Chile), #NODATA#, Guerra-Varas, N., Merello, M., Bronfman, L., Duronea, N., Elia, D., Finger, R., and Mendoza, E.
Abstract: (Abridged) High-mass star formation is far less understood than low-mass star formation. It entails molecular outflows, which disturb the protostellar clump. Studying these outflows and the shocked gas they cause is key for a better understanding of this process. This study aims to characterise the behaviour of molecular outflows in the most massive protostellar sources in the Southern Galaxy by looking for evolutionary trends and associating shocked gas with outflow activity. We present APEX SEPIA180 observations (beamwidth $\sim$36") of SiO outflow candidates of a sample of 32 luminous and dense clumps, candidates to harbouring Hot Molecular Cores. We study the SiO(4-3) line emission, an unambiguous tracer of shocked gas and recent outflow activity, the HCO$^+$(2-1) and H$^{13}$CO$^+$(2-1) lines. 78% of our sample present SiO emission. Nine of these also have wings in the HCO$^+$ line, indicating outflow activity. The SiO emission of these 9 sources is more intense and wider than the rest, suggesting that the outflows in this group are faster and more energetic. Three positive correlations between the outflow properties were found, which suggest that more energetic outflows bear to mobilise more material. No correlation was found between the evolutionary stage indicator $L/M$ and SiO outflow properties, supporting that outflows happen throughout the whole high-mass star formation process. We conclude that sources with both SiO emission and HCO$^+$ wings and sources with only SiO emission are in virtually the same advanced stage of evolution in the high-mass star formation process. The former present more massive and more powerful SiO outflows than the latter. Thus, looking for more outflow signatures such as HCO$^+$ wings could help identify more massive and active massive star-forming regions in samples of similarly evolved sources, as well as sources with older outflow activity.
Published: 2023

3. Smooth kinematic and metallicity gradients reveal that the Milky Way’s nuclear star cluster and disc might be part of the same structure

Author: European Southern Observatory, Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Ministerio de Ciencia e Innovación (España), Nogueras Lara, Francisco, Feldmeier-Krause, A., Schödel, Rainer, Sormani, M. C., de Lorenzo-Cáceres, A., Mastrobuono-Battisti, A., Schultheis, M., Neumayer, N., Rich, R. M., Nieuwmunster, N., European Southern Observatory, Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Ministerio de Ciencia e Innovación (España), Nogueras Lara, Francisco, Feldmeier-Krause, A., Schödel, Rainer, Sormani, M. C., de Lorenzo-Cáceres, A., Mastrobuono-Battisti, A., Schultheis, M., Neumayer, N., Rich, R. M., and Nieuwmunster, N.
Abstract: Context. The innermost regions of most galaxies are characterised by the presence of extremely dense nuclear star clusters. Nevertheless, these clusters are not the only stellar component present in galactic nuclei, where larger stellar structures known as nuclear stellar discs, have also been found. Understanding the relation between nuclear star clusters and nuclear stellar discs is challenging due to the large distance towards other galaxies which limits their analysis to integrated light. The Milky Way’s centre, at only ~8 kpc, hosts a nuclear star cluster and a nuclear stellar disc, constituting a unique template to understand their relation and formation scenario. Aims. We aim to study the kinematics and stellar metallicity of stars from the Milky Way’s nuclear star cluster and disc to shed light on the relation between these two Galactic centre components. Methods. We used publicly available photometric, proper motions, and spectroscopic catalogues to analyse a region of ~2.8′ × 4.9′ centred on the Milky Way’s nuclear star cluster. We built colour magnitude diagrams, and applied colour cuts to analyse the kinematic and metallicity distributions of Milky Way’s nuclear star cluster and disc stars with different extinction, along the line of sight. Results. We detect kinematic and metallicity gradients for the analysed stars along the line of sight towards the Milky Way’s nuclear star cluster, suggesting a smooth transition between the nuclear stellar disc and cluster.We also find a bi-modal metallicity distribution for all the analysed colour bins, which is compatible with previous work on the bulk population of the nuclear stellar disc and cluster. Our results suggest that these two Galactic centre components might be part of the same structure with the Milky Way’s nuclear stellar disc being the grown edge of the nuclear star cluster. © The Authors 2023
Published: 2023

4. The Compact binary HIgh CAdence Survey (CHiCaS): An overview

Author: Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. GAA - Grup d'Astronomia i Astrofísica, European Southern Observatory, University of Warwick, Universidade de São Paulo, European Southern Observatory Chile, Centro de Estudios de Física del Cosmos de Aragón, Pala, A. F., Ederoclite, A, Gänsicke, Boris T., Abril, J, Raddi, Roberto, Vázquez Ramió, H, Rebassa Mansergas, Alberto, Universitat Politècnica de Catalunya. Departament de Física, Universitat Politècnica de Catalunya. GAA - Grup d'Astronomia i Astrofísica, European Southern Observatory, University of Warwick, Universidade de São Paulo, European Southern Observatory Chile, Centro de Estudios de Física del Cosmos de Aragón, Pala, A. F., Ederoclite, A, Gänsicke, Boris T., Abril, J, Raddi, Roberto, Vázquez Ramió, H, and Rebassa Mansergas, Alberto
Abstract: Cataclysmic Variables (CVs) are binaries in which a white dwarf accretes from a low-mass companion star. CVs are the best-suited laboratories to test our understanding of the evolution of compact, interacting binaries as they are numerous, relatively bright, and both stellar components are structurally simple. Nonetheless, while a large fraction ( ) of the present-day Galactic CV population is expected to be old, highly evolved and to host brown dwarf companions, yet very few of these so-called “period bouncers” have been identified so far. The lack of these systems in the observed Galactic CV population possibly suggests that the physical mechanisms driving CV evolution (such as the common envelope phase, the mechanisms of angular momentum loss and/or the response of the companions to the mass loss) are still not completely understood. The Compact binary HIgh CAdence Survey (CHiCaS) is a high cadence photometric survey performing three hours of uninterrupted time series photometry at one minute cadence over 136 square degrees of sky with JAST/T80Cam. CHiCaS aims to unambiguously identify the predicted large population of period-bounce CVs via detection of binary eclipses, thus providing an observational support for the current evolutionary models of all kind of compact binaries, such as black hole binaries, X-ray transients, double degenerates or SN Ia progenitors. Moreover, CHiCaS will deliver high cadence light curves along with full-colour information for about 2.5 million sources, thus identifying several hundred thousand variable stars, including eclipsing and contact binaries, pulsating and flaring stars, which will provide a significant legacy value., Peer Reviewed, Postprint (published version)
Published: 2020

5. Organic Molecules in Interstellar Space: Latest advances

Author: European Commission, Ministerio de Ciencia, Innovación y Universidades (España), European Southern Observatory, National Science Foundation (US), National Institutes of Natural Sciences (Japan), National Research Council of Canada, Ministry of Science and Technology (Taiwan), Academia Sinica (Taiwan), Korea Astronomy and Space Science Institute, Centre National de la Recherche Scientifique (France), Max Planck Society, Instituto Geográfico Nacional (España), Guélin, Michel, Cernicharo, José, European Commission, Ministerio de Ciencia, Innovación y Universidades (España), European Southern Observatory, National Science Foundation (US), National Institutes of Natural Sciences (Japan), National Research Council of Canada, Ministry of Science and Technology (Taiwan), Academia Sinica (Taiwan), Korea Astronomy and Space Science Institute, Centre National de la Recherche Scientifique (France), Max Planck Society, Instituto Geográfico Nacional (España), Guélin, Michel, and Cernicharo, José
Abstract: Although first considered as too diluted for the formation of molecules in-situ and too harsh an environment for their survival, the interstellar medium has turned out to host a rich palette of molecular species: to date, 256 species, not counting isotopologues, have been identified. The last decade, and more particularly the last 2 years, have seen an explosion of new detections, including those of a number of complex organic species, which may be dubbed as prebiotic. Organic molecules have been discovered not just in interstellar clouds from the Solar neighbourhood, but also throughout the Milky-Way, as well as in nearby galaxies, or some of the most distant quasars. These discoveries were made possible by the completion of large sub-millimetre and radio facilities. Equipped with new generation receivers, those instruments have provided the orders of magnitude leap in sensitivity required to detect the vanishingly weak rotational lines that allowed the molecule identifications. Last 2 years, 30 prebiotic molecules have been detected in TMC-1, a dustenshrouded gaseous cloud located at 400 light-years from the Sun in the Taurus constellation. Ten new molecular species, have been identified in the arm of a spiral galaxy seven billion light-yr distant, and 12 molecular species observed in a quasar at 11 billion light-yr. We present the latest spectral observations of this outlying quasar and discuss the implications of those detections in these 3 archetypal sources. The basic ingredients involved in the Miller-Urey experiment and related experiments (H2, H2O, CH4, NH3, CO, H2S, ... ) appeared early after the formation of the first galaxies and are widespread throughout the Universe. The chemical composition of the gas in distant galaxies seems not much different from that in the nearby interstellar clouds. It presumably comprises, like for TMC-1, aromatic rings and complex organic molecules putative precursors of the RNA nucleobases, except the lines of such complex s
Published: 2022

6. The HST See Change Program. I. Survey Design, Pipeline, and Supernova Discoveries

Author: Gemini Observatory, National Science Foundation (US), National Research Council of Canada, Comisión Nacional de Investigación Científica y Tecnológica (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), Ministério da Ciência, Tecnologia e Inovação (Brasil), Korea Astronomy and Space Science Institute, European Southern Observatory, National Aeronautics and Space Administration (US), German Research Foundation, European Commission, Hayden, Brian, Rubin, David, Boone, Kyle, Aldering, Greg, Nordin, Jakob, Brodwin, Mark, Deustua, Susana, Dixon, Sam, Fagrelius, Parker, Fruchter, Andrew S., Eisenhardt, Peter, Gonzalez, Anthony, Gupta, Ravi, Hook, Isobel, Lidman, Chris, Luther, Kyle, Muzzin, Adam, Raha, Zachary, Ruiz-Lapuente, Pilar, Saunders, Clare, Sofiatti, Caroline, Stanford, Adam, Suzuki, Nao, Webb, Tracy, Williams, Steven C., Wilson, Gillian, Yen, Mike, Amanullah, Rahman, Barbary, Kyle, Böhringer, Hans, Chappell, Greta, Cunha, Carlos, Currie, Miles, Fassbender, Rene, Gladders, Michael, Goobar, Ariel, Hildebrandt, Hendrik, Hoekstra, Henk, Huang, Xiaosheng, Huterer, Dragan, Jee, M. James, Kim, Alex, Kowalski, Marek, Linder, Eric, Meyers, Joshua E., Pain, Reynald, Perlmutter, Saul, Richard, Johan, Rosati, Piero, Rozo, Eduardo, Rykoff, Eli, Santos, Joana, Spadafora, Anthony, Stern, Daniel, Wechsler, Risa, Gemini Observatory, National Science Foundation (US), National Research Council of Canada, Comisión Nacional de Investigación Científica y Tecnológica (Chile), Ministerio de Ciencia, Tecnología e Innovación Productiva (Argentina), Ministério da Ciência, Tecnologia e Inovação (Brasil), Korea Astronomy and Space Science Institute, European Southern Observatory, National Aeronautics and Space Administration (US), German Research Foundation, European Commission, Hayden, Brian, Rubin, David, Boone, Kyle, Aldering, Greg, Nordin, Jakob, Brodwin, Mark, Deustua, Susana, Dixon, Sam, Fagrelius, Parker, Fruchter, Andrew S., Eisenhardt, Peter, Gonzalez, Anthony, Gupta, Ravi, Hook, Isobel, Lidman, Chris, Luther, Kyle, Muzzin, Adam, Raha, Zachary, Ruiz-Lapuente, Pilar, Saunders, Clare, Sofiatti, Caroline, Stanford, Adam, Suzuki, Nao, Webb, Tracy, Williams, Steven C., Wilson, Gillian, Yen, Mike, Amanullah, Rahman, Barbary, Kyle, Böhringer, Hans, Chappell, Greta, Cunha, Carlos, Currie, Miles, Fassbender, Rene, Gladders, Michael, Goobar, Ariel, Hildebrandt, Hendrik, Hoekstra, Henk, Huang, Xiaosheng, Huterer, Dragan, Jee, M. James, Kim, Alex, Kowalski, Marek, Linder, Eric, Meyers, Joshua E., Pain, Reynald, Perlmutter, Saul, Richard, Johan, Rosati, Piero, Rozo, Eduardo, Rykoff, Eli, Santos, Joana, Spadafora, Anthony, Stern, Daniel, and Wechsler, Risa
Abstract: The See Change survey was designed to make z > 1 cosmological measurements by efficiently discovering high-redshift Type Ia supernovae (SNe Ia) and improving cluster mass measurements through weak lensing. This survey observed twelve galaxy clusters with the Hubble Space Telescope (HST) spanning the redshift range z = 1.13-1.75, discovering 57 likely transients and 27 likely SNe Ia at z ~ 0.8-2.3. As in similar previous surveys, this proved to be a highly efficient use of HST for supernova observations; the See Change survey additionally tested the feasibility of maintaining, or further increasing, the efficiency at yet higher redshifts, where we have less detailed information on the expected cluster masses and star formation rates. We find that the resulting number of SNe Ia per orbit is a factor of ~8 higher than for a field search, and 45% of our orbits contained an active SN Ia within 22 rest-frame days of peak, with one of the clusters by itself yielding 6 of the SNe Ia. We present the survey design, pipeline, and supernova discoveries. Novel features include fully blinded supernova searches, the first random forest candidate classifier for undersampled IR data (with a 50% detection threshold within 0.05 mag of human searchers), real-time forward-modeling photometry of candidates, and semi-automated photometric classifications and follow-up forecasts. We also describe the spectroscopic follow-up, instrumental in measuring host galaxy redshifts. The cosmology analysis of our sample will be presented in a companion paper. * Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555, under programs 13677, 14327.
Published: 2021

7. Wolf-Rayet stars in the Antennae unveiled by MUSE

Author: Universidad Nacional Autónoma de México, European Southern Observatory, National Aeronautics and Space Administration (US), Gómez-González, V. M. A., Mayya, Y. D., Toalá, J. A., Arthur, S. J., Zaragoza-Cardiel, J., Guerrero, Martín A., Universidad Nacional Autónoma de México, European Southern Observatory, National Aeronautics and Space Administration (US), Gómez-González, V. M. A., Mayya, Y. D., Toalá, J. A., Arthur, S. J., Zaragoza-Cardiel, J., and Guerrero, Martín A.
Abstract: We present the analysis of archival Very Large Telescope (VLT) Multi-Unit Spectroscopic Explorer (MUSE) observations of the interacting galaxies NGC 4038/39 (a.k.a. the Antennae) at a distance of 18.1 Mpc. Up to 38 young star-forming complexes with evident contribution from Wolf-Rayet (WR) stars are unveiled. We use publicly available templates of Galactic WR stars in conjunction with available photometric extinction measurements to quantify and classify the WR population in each star-forming region, on the basis of its nearly Solar oxygen abundance. The total estimated number of WR stars in the Antennae is 4053 ± 84, of which there are 2021 ± 60 WNL and 2032 ± 59 WC-types. Our analysis suggests a global WC to WN-type ratio of 1.01 ± 0.04, which is consistent with the predictions of the single star evolutionary scenario in the most recent bpass stellar population synthesis models. © 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.
Published: 2021

8. Structure and dynamics of the inner nebula around the symbiotic stellar system R Aquarii

Author: Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), National Science Centre (Poland), European Commission, National Research Foundation of Korea, European Southern Observatory, National Science Foundation (US), National Institutes of Natural Sciences (Japan), National Research Council of Canada, Academia Sinica (Taiwan), Korea Astronomy and Space Science Institute, Bujarrabal, V., Agúndez, Marcelino, Gómez-Garrido, M., Kim, H., Santander-García, M., Alcolea, J., Castro-Carrizo, A., Mikołajewska, J., Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), National Science Centre (Poland), European Commission, National Research Foundation of Korea, European Southern Observatory, National Science Foundation (US), National Institutes of Natural Sciences (Japan), National Research Council of Canada, Academia Sinica (Taiwan), Korea Astronomy and Space Science Institute, Bujarrabal, V., Agúndez, Marcelino, Gómez-Garrido, M., Kim, H., Santander-García, M., Alcolea, J., Castro-Carrizo, A., and Mikołajewska, J.
Abstract: Aims. We investigate the structure, dynamics, and chemistry of the molecule-rich nebula around the stellar symbiotic system R Aqr, which is significantly affected by the presence of a white dwarf (WD) companion. We study the effects of the strong dynamical interaction between the AGB wind and the WD and of photodissociation by the WD UV radiation on the circumstellar shells. Methods. We obtained high-quality ALMA maps of the 12CO J = 2-1, J = 3-2, and J = 6-5 lines and of 13CO J = 3-2. The maps were analyzed by means of a heuristic 3D model that is able to reproduce the observations. In order to interpret this description of the molecule-rich nebula, we performed sophisticated calculations of hydrodynamical interaction and photoinduced chemistry. Results. We find that the CO-emitting gas is distributed within a relatively small region â‰² 1.″5. Its structure consists of a central dense component plus strongly disrupted outer regions, which seem to be parts of spiral arms that are highly focused on the orbital plane. The structure and dynamics of these spiral arms are compatible with our hydrodynamical calculations. We argue that the observed nebula is the result of the dynamical interaction between the wind and the gravitational attraction of the WD. We also find that UV emission from the hot companion efficiently photodissociates molecules except in the densest and best-shielded regions, that is, in the close surroundings of the AGB star and some shreds of the spiral arms from which the detected lines come. We can offer a faithful description of the distribution of nebular gas in this prototypical source, which will be a useful template for studying material around other tight binary systems.
Published: 2021

9. DEATHSTAR: Nearby AGB stars with the Atacama Compact Array: II. CO envelope sizes and asymmetries: The S-type stars

Author: European Southern Observatory, National Science Foundation (US), National Institutes of Natural Sciences (Japan), National Research Council of Canada, Ministry of Science and Technology (Taiwan), Academia Sinica (Taiwan), Korea Astronomy and Space Science Institute, Swedish Research Council, Andriantsaralaza, M., Ramstedt, S., Vlemmings, W.H.T., Danilovich, T., Beck, E. de, Groenewegen, M.A.T., Höfner, S., Kerschbaum, F., Khouri, T., Lindqvist, M., Maercker, M., Olofsson, H., Quintana-Lacaci, G., Saberi, M., Sahai, R., Zijlstra, A., European Southern Observatory, National Science Foundation (US), National Institutes of Natural Sciences (Japan), National Research Council of Canada, Ministry of Science and Technology (Taiwan), Academia Sinica (Taiwan), Korea Astronomy and Space Science Institute, Swedish Research Council, Andriantsaralaza, M., Ramstedt, S., Vlemmings, W.H.T., Danilovich, T., Beck, E. de, Groenewegen, M.A.T., Höfner, S., Kerschbaum, F., Khouri, T., Lindqvist, M., Maercker, M., Olofsson, H., Quintana-Lacaci, G., Saberi, M., Sahai, R., and Zijlstra, A.
Abstract: Aims. We aim to constrain the sizes of, and investigate deviations from spherical symmetry in, the CO circumstellar envelopes (CSEs) of 16 S-type stars, along with an additional 7 and 4 CSEs of C-type and M-type AGB stars, respectively. Methods. We map the emission from the CO J = 2-1 and 3-2 lines observed with the Atacama Compact Array (ACA) and its total power (TP) antennas, and fit with a Gaussian distribution in the uv- and image planes for ACA-only and TP observations, respectively. The major axis of the fitted Gaussian for the CO(2-1) line data gives a first estimate of the size of the CO-line-emitting CSE. We investigate possible signs of deviation from spherical symmetry by analysing the line profiles and the minor-to-major axis ratio obtained from visibility fitting, and by investigating the deconvolved images. Results. The sizes of the CO-line-emitting CSEs of low-mass-loss-rate (low-MLR) S-type stars fall between the sizes of the CSEs of C-stars, which are larger, and those of M-stars, which are smaller, as expected because of the differences in their respective CO abundances and the dependence of the photodissociation rate on this quantity. The sizes of the low-MLR S-type stars show no dependence on circumstellar density, as measured by the ratio of the MLR to terminal outflow velocity, irrespective of variability type. The density dependence steepens for S-stars with higher MLRs. While the CO(2-1) brightness distribution size of the low-density S-stars is in general smaller than the predicted photodissociation radius (assuming the standard interstellar radiation field), the measured size of a few of the high-density sources is of the same order as the expected photodissociation radius. Furthermore, our results show that the CO CSEs of most of the S-stars in our sample are consistent with a spherically symmetric and smooth outflow. For some of the sources, clear and prominent asymmetric features are observed which are indicative of intrinsic circumstell
Published: 2021

10. Asteroid (16) Psyche's primordial shape: A possible Jacobi ellipsoid

Author: European Southern Observatory, Centre National de la Recherche Scientifique (France), Czech Science Foundation, Charles University (Czech Republic), Generalitat Valenciana, European Commission, Ministerio de Economía y Competitividad (España), Ferrais, M., Vernazza, Pierre, Jorda, Laurent, Rambaux, N., Hanuš, J., Carry, B., Marchis, F., Marsset, M., Viikinkoski, M., Brož, M., Fetick, R., Drouard, A., Fusco, Thierry, Birlan, M., Podlewska-Gaca, E., Jehin, Emmanuël, Bartczak, P., Castillo-Rogez, J., Cipriani, Fabrice, Colas, François, Dudziński, G., Dumas, C., Ğ Urech, J., Kaasalainen, Mikko, Kryszczynska, A., Lamy, P., Le Coroller, H., Marciniak, A., Michalowski, T., Michel, P., Santana-Ros, Toni, Tanga, P., Vachier, F., Vigan, A., Witasse, O., Yang, B., European Southern Observatory, Centre National de la Recherche Scientifique (France), Czech Science Foundation, Charles University (Czech Republic), Generalitat Valenciana, European Commission, Ministerio de Economía y Competitividad (España), Ferrais, M., Vernazza, Pierre, Jorda, Laurent, Rambaux, N., Hanuš, J., Carry, B., Marchis, F., Marsset, M., Viikinkoski, M., Brož, M., Fetick, R., Drouard, A., Fusco, Thierry, Birlan, M., Podlewska-Gaca, E., Jehin, Emmanuël, Bartczak, P., Castillo-Rogez, J., Cipriani, Fabrice, Colas, François, Dudziński, G., Dumas, C., Ğ Urech, J., Kaasalainen, Mikko, Kryszczynska, A., Lamy, P., Le Coroller, H., Marciniak, A., Michalowski, T., Michel, P., Santana-Ros, Toni, Tanga, P., Vachier, F., Vigan, A., Witasse, O., and Yang, B.
Abstract: Context. Asteroid (16) Psyche is the largest M-type asteroid in the main belt and the target of the NASA Psyche mission. It is also the only asteroid of this size (D> 200 km) known to be metal rich. Although various hypotheses have been proposed to explain the rather unique physical properties of this asteroid, a perfect understanding of its formation and bulk composition is still missing. Aims. We aim to refine the shape and bulk density of (16) Psyche and to perform a thorough analysis of its shape to better constrain possible formation scenarios and the structure of its interior. Methods. We obtained disk-resolved VLT/SPHERE/ZIMPOL images acquired within our ESO large program (ID 199.C-0074), which complement similar data obtained in 2018. Both data sets offer a complete coverage of Psyche's surface. These images were used to reconstruct the three-dimensional (3D) shape of Psyche with two independent shape modeling algorithms (MPCD and ADAM). A shape analysis was subsequently performed, including a comparison with equilibrium figures and the identification of mass deficit regions. Results. Our 3D shape along with existing mass estimates imply a density of 4.20 ± 0.60 g cm-3, which is so far the highest for a solar system object following the four telluric planets. Furthermore, the shape of Psyche presents small deviations from an ellipsoid, that is, prominently three large depressions along its equator. The flatness and density of Psyche are compatible with a formation at hydrostatic equilibrium as a Jacobi ellipsoid with a shorter rotation period of ∼3h. Later impacts may have slowed down Psyche's rotation, which is currently ∼4.2 h, while also creating the imaged depressions. Conclusions. Our results open the possibility that Psyche acquired its primordial shape either after a giant impact while its interior was already frozen or while its interior was still molten owing to the decay of the short-lived radionuclide 26Al.
Published: 2020

11. A statistical analysis of dust polarization properties in ALMA observations of Class 0 protostellar cores

Author: European Southern Observatory, Ministerio de Ciencia, Innovación y Universidades (España), Japan Society for the Promotion of Science, National Astronomical Observatory of Japan, European Commission, Le Gouellec, Valentin J. M., Maury, Anaëlle, Guillet, V., Hull, Charles L. H., Girart, Josep Miquel, Verliat, A., Mignon-Risse, R., Valdivia, Valeska, Hennebelle, Patrick, González, Matthias Carmen, European Southern Observatory, Ministerio de Ciencia, Innovación y Universidades (España), Japan Society for the Promotion of Science, National Astronomical Observatory of Japan, European Commission, Le Gouellec, Valentin J. M., Maury, Anaëlle, Guillet, V., Hull, Charles L. H., Girart, Josep Miquel, Verliat, A., Mignon-Risse, R., Valdivia, Valeska, Hennebelle, Patrick, and González, Matthias Carmen
Abstract: Context. Recent observational progress has challenged the dust grain-alignment theories used to explain the polarized dust emission routinely observed in star-forming cores. Aims. In an effort to improve our understanding of the dust grain alignment mechanism(s), we have gathered a dozen ALMA maps of (sub)millimeter-wavelength polarized dust emission from Class 0 protostars and carried out a comprehensive statistical analysis of dust polarization quantities. Methods. We analyze the statistical properties of the polarization fraction Pfrac and the dispersion of polarization position angles S. More specifically, we investigate the relationship between S and Pfrac as well as the evolution of the product S × Pfrac as a function of the column density of the gas in the protostellar envelopes. We compare the observed trends with those found in polarization observations of dust in the interstellar medium and in synthetic observations of non-ideal magneto-hydrodynamic (MHD) simulations of protostellar cores. Results. We find a significant S Pfrac-0.79 correlation in the polarized dust emission from protostellar envelopes seen with ALMA; the power-law index significantly differs from the one observed by Planck in star-forming clouds. The product S × Pfrac, which is sensitive to the dust grain alignment efficiency, is approximately constant across three orders of magnitude in envelope column density (from NH2 = 1022 cm-2 to NH2 = 1025 cm-2), with a mean value of 0.36-0.17+0.10. This suggests that the grain alignment mechanism producing the bulk of the polarized dust emission in star-forming cores may not systematically depend on the local conditions such as the local gas density. However, in the lowest-luminosity sources in our sample, we find a hint of less efficient dust grain alignment with increasing column density. Our observations and their comparison with synthetic observations of MHD models suggest that the total intensity versus the polarized dust are distributed at d
Published: 2020

12. DEATHSTAR: Nearby AGB stars with the Atacama Compact Array: I. CO envelope sizes and asymmetries: A new hope for accurate mass-loss-rate estimates

Author: European Southern Observatory, National Science Foundation (US), National Institutes of Natural Sciences (Japan), National Research Council of Canada, Ministry of Science and Technology (Taiwan), Academia Sinica (Taiwan), Korea Astronomy and Space Science Institute, European Space Agency, Ramstedt, S., Vlemmings, W.H.T., Doan, L., Danilovich, T., Lindqvist, M., Saberi, M., Olofsson, H., De Beck, E., Groenewegen, M.A.T., Höfner, S., Kastner, J.H., Kerschbaum, F., Khouri, T., Maercker, M., Montez, R., Quintana-Lacaci, G., Sahai, R., Tafoya, D., Zijlstra, A., European Southern Observatory, National Science Foundation (US), National Institutes of Natural Sciences (Japan), National Research Council of Canada, Ministry of Science and Technology (Taiwan), Academia Sinica (Taiwan), Korea Astronomy and Space Science Institute, European Space Agency, Ramstedt, S., Vlemmings, W.H.T., Doan, L., Danilovich, T., Lindqvist, M., Saberi, M., Olofsson, H., De Beck, E., Groenewegen, M.A.T., Höfner, S., Kastner, J.H., Kerschbaum, F., Khouri, T., Maercker, M., Montez, R., Quintana-Lacaci, G., Sahai, R., Tafoya, D., and Zijlstra, A.
Abstract: Context. This is the first publication from the DEATHSTAR project. The overall goal of the project is to reduce the uncertainties of the observational estimates of mass-loss rates from evolved stars on the Asymptotic Giant Branch (AGB). Aim. The aim in this first publication is to constrain the sizes of the 12CO emitting region from the circumstellar envelopes around 42 mostly southern AGB stars, of which 21 are M-Type and 21 are C-Type, using the Atacama Compact Array (ACA) at the Atacama Large Millimeter/submillimeter Array. The symmetry of the outflows is also investigated. Methods. Line emission from 12CO J = 2→1 and 3→2 from all of the sources were mapped using the ACA. In this initial analysis, the emission distribution was fit to a Gaussian distribution in the uv-plane. A detailed radiative transfer analysis will be presented in a future publication. The major and minor axis of the best-fit Gaussian at the line center velocity of the 12CO J = 2→1 emission gives a first indication of the size of the emitting region. Furthermore, the fitting results, such as the Gaussian major and minor axis, center position, and the goodness of fit across both lines, constrain the symmetry of the emission distribution. For a subsample of sources, the measured emission distribution is compared to predictions from previous best-fit radiative transfer modeling results. Results. We find that the CO envelope sizes are, in general, larger for C-Type than for M-Type AGB stars, which is as expected if the CO/H2 ratio is larger in C-Type stars. Furthermore, the measurements show a relation between the measured (Gaussian) 12CO J = 2→1 size and circumstellar density that, while in broad agreement with photodissociation calculations, reveals large scatter and some systematic differences between the different stellar types. For lower mass-loss-rate irregular and semi-regular variables of both M-and C-Type AGB stars, the 12CO J = 2→1 size appears to be independent of the ratio of the mass-l
Published: 2020

13. See Change: VLT spectroscopy of a sample of high-redshift Type Ia supernova host galaxies

Author: Science and Technology Facilities Council (UK), European Southern Observatory, National Aeronautics and Space Administration (US), European Space Agency, Hubble Space Telescope, Space Telescope Science Institute (US), California Institute of Technology, California State University, W. M. Keck Foundation, Williams, S. C., Hook, I. M., Hayden, B., Nordin, J., Aldering, G., Boone, K., Goobar, A., Lidman, C. E., Perlmutter, S., Rubin, D., Ruiz-Lapuente, Pilar, Saunders, C., Science and Technology Facilities Council (UK), European Southern Observatory, National Aeronautics and Space Administration (US), European Space Agency, Hubble Space Telescope, Space Telescope Science Institute (US), California Institute of Technology, California State University, W. M. Keck Foundation, Williams, S. C., Hook, I. M., Hayden, B., Nordin, J., Aldering, G., Boone, K., Goobar, A., Lidman, C. E., Perlmutter, S., Rubin, D., Ruiz-Lapuente, Pilar, and Saunders, C.
Abstract: The Supernova Cosmology Project has conducted the 'See Change' programme, aimed at discovering and observing high-redshift (1.13 ¿ z ¿ 1.75) Type Ia supernovae (SNe Ia). We used multifilter Hubble Space Telescope (HST) observations of massive galaxy clusters with sufficient cadence to make the observed SN Ia light curves suitable for a cosmological probe of dark energy at z > 0.5. This See Change sample of SNe Ia with multi-colour light curves will be the largest to date at these redshifts. As part of the See Change programme, we obtained ground-based spectroscopy of each discovered transient and/or its host galaxy. Here, we present Very Large Telescope (VLT) spectra of See Change transient host galaxies, deriving their redshifts, and host parameters such as stellar mass and star formation rate. Of the 39 See Change transients/hosts that were observed with the VLT, we successfully determined the redshift for 26, including 15 SNe Ia at z > 0.97. We show that even in passive environments, it is possible to recover secure redshifts for the majority of SN hosts out to z = 1.5. We find that with typical exposure times of 3-4 h on an 8-m-class telescope we can recover ~75 per cent of SN Ia redshifts in the range of 0.97 < z < 1.5. Furthermore, we show that the combination of HST photometry and VLT spectroscopy is able to provide estimates of host galaxy stellar mass that are sufficiently accurate for use in a mass-step correction in the cosmological analysis.
Published: 2020

14. AGN and star formation properties of inside-out assembled galaxy candidates at z < 0.1

Author: European Southern Observatory, Ministry of Science and Technology (Ethiopia), Debre Birhan University, Ministerio de Ciencia e Innovación (España), European Commission, Comisión Nacional de Investigación Científica y Tecnológica (Chile), Leverhulme Trust, Zewdie, Dejen, Pović, Mirjana, Aravena, Manuel, Assef, Roberto J., Gaulle, Asrate, European Southern Observatory, Ministry of Science and Technology (Ethiopia), Debre Birhan University, Ministerio de Ciencia e Innovación (España), European Commission, Comisión Nacional de Investigación Científica y Tecnológica (Chile), Leverhulme Trust, Zewdie, Dejen, Pović, Mirjana, Aravena, Manuel, Assef, Roberto J., and Gaulle, Asrate
Abstract: We study a sample of 48 127 galaxies selected from the SDSS MPA-JHU catalogue, with log M-star/M-circle dot = 10.73-11.03 and z < 0.1. Local galaxies in this stellar mass range have been shown to have systematically shorter assembly times within their inner regions (<0.5 R-50) when compared to that of the galaxy as a whole, contrary to lower or higher mass galaxies that show consistent assembly times at all radii. Hence, we refer to these galaxies as Inside-Out Assembled Galaxy (IOAG) candidates. We find that the majority of IOAG candidates with well-detected emission lines are classified as either active galactic nucleus (AGN; 40 per cent) or composite (40 per cent) in the BPT (Baldwin, Phillips & Terlevich) diagram. We also find that the majority of our sources are located below the main sequence of star formation, and within the green valley or red sequence. Most BPT-classified star-forming IOAG candidates have spiral morphologies and are in the main sequence, whereas Seyfert 2 and composites have mostly spiral morphologies but quiescent star formation rates (SFRs). We argue that a high fraction of IOAG candidates seem to be in the process of quenching, moving from the blue cloud to the red sequence. Those classified as AGN have systematically lower SFRs than star-forming galaxies, suggesting that AGN activity may be related to this quenching. However, the spiral morphology of these galaxies remains in place, suggesting that the central star formation is suppressed before the morphological transformation occurs. © 2020 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society
Published: 2020

15. Search for Be-7 in the outbursts of four recent novae

Author: Villum Fonden, European Southern Observatory, Molaro, P., Izzo, L., Bonifacio, P., Hernanz, Margarita, Selvelli, P., Della Valle, M., Villum Fonden, European Southern Observatory, Molaro, P., Izzo, L., Bonifacio, P., Hernanz, Margarita, Selvelli, P., and Della Valle, M.
Abstract: Following the recent detection of Be-7 II in the outburst spectra of classical novae, we report the search for this isotope in the outbursts of four recent bright novae by means of high-resolution Ultraviolet and Visual Echelle Spectrograph (UVES) observations. The Be-7 II lambda lambda 313.0583,313.1228 nm doublet resonance lines are detected in the high-velocity components of Nova Mus 2018 and ASASSN-18fv during outbursts. However, 7Be?II is not detected in ASASSN-17hx and possibly not in Nova Cir 2018, which shows that 7Be is not always ejected in the thermonuclear runaway. Taking into account the Be-7 decay, we find X(Be-7)/X(H) approximate to 1.5 x 10(-5) and 2.2 x 10(-5) in Nova Mus 2018 and ASASSN-18fv, respectively. A value of 7Be/H approximate to 2 x 10(-5) is found in five out of the seven extant measurements, and it can be considered as a typical 7Be yield for novae. However, this value is almost one order of magnitude larger than predicted by current theoretical models. We argue that the variety of high Be-7/H abundances could be the result of a higher than solar content of 3He in the donor star. The cases with Be-7 not detected might be related to the small mass of the white dwarf (WD) or to relatively little mixing with the core material of the WD. The Be-7/H, or Li-7/H, abundance is approximate to 4 dex above meteoritic abundance, thus confirming the novae as the main sources of Li-7 in the Milky Way.
Published: 2020

16. New constraints on the structure of the nuclear stellar cluster of the Milky Way from star counts and MIR imaging

Author: European Research Council, European Southern Observatory, German Research Foundation, Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Gallego Cano, Eulalia, Schödel, Rainer, Nogueras Lara, Francisco, Dong, H., Shahzamanian, B., Fritz, T. K., Gallego Calvente, Teresa, Neumayer, N., European Research Council, European Southern Observatory, German Research Foundation, Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Gallego Cano, Eulalia, Schödel, Rainer, Nogueras Lara, Francisco, Dong, H., Shahzamanian, B., Fritz, T. K., Gallego Calvente, Teresa, and Neumayer, N.
Abstract: Context. The Milky Way nuclear star cluster (MWNSC) is a crucial laboratory for studying the galactic nuclei of other galaxies, but its properties have not been determined unambiguously until now.Aims. We aim to study the size and spatial structure of the MWNSC.Methods. This study uses data and methods that address potential shortcomings of previous studies on the topic. We use 0.2 '' angular resolution K-s data to create a stellar density map in the central 86.4 pc x 21 pc at the Galactic center. We include data from selected adaptive-optics-assisted images obtained for the inner parsecs. In addition, we use Spitzer/IRAC mid-infrared (MIR) images. We model the Galactic bulge and the nuclear stellar disk in order to subtract them from the MWNSC. Finally, we fit a Sersic model to the MWNSC and investigate its symmetry.Results. Our results are consistent with previous work. The MWNSC is flattened with an axis ratio of q=0.710.10, an effective radius of R-e=(5.1 +/- 1.0) pc, and a Sersic index of n=2.2 +/- 0.7. Its major axis may be tilted out of the Galactic plane by up to -10 degrees. The distribution of the giants brighter than the Red Clump (RC) is found to be significantly flatter than the distribution of the faint stars. We investigate the 3D structure of the central stellar cusp using our results on the MWNSC structure on large scales to constrain the deprojection of the measured stellar surface number density, obtaining a value of the 3D inner power law of gamma=1.38 +/- 0.06(sys)+/- 0.01(stat).Conclusions. The MWNSC shares its main properties with other extragalactic NSCs found in spiral galaxies. The differences in the structure between bright giants and RC stars might be related to the existence of not completely mixed populations of different ages. This may hint at recent growth of the MWNSC through star formation or cluster accretion.© ESO 2020
Published: 2020

17. Planetary system around the nearby M dwarf GJ 357 including a transiting, hot, Earth-sized planet optimal for atmospheric characterization

Author: National Aeronautics and Space Administration (US), Max Planck Society, Consejo Superior de Investigaciones Científicas (España), European Commission, Ministerio de Economía y Competitividad (España), German Research Foundation, Klaus Tschira Foundation, Heising Simons Foundation, Ministry of Education, Culture, Sports, Science and Technology (Japan), Japan Society for the Promotion of Science, European Southern Observatory, Luque, R., Pallé, Enric, Kossakowski, D., Dreizler, S., Kemmer, J., Espinoza, Néstor, Burt, J., Anglada-Escudé, Guillem, Béjar, Victor J. S., Caballero, J. A., Collins, Karen A., Collins, KI., Cortés-Contreras, M., Díez-Alonso, E., Feng, Fabo, Hatzes, Artie P., Hellier, C, Henning, Thomas, Jeffers, Sandra V., Kaltenegger, L., Kürster, M., Madden, J., Molaverdikhani, K., Montes, D., Narita, N., Nowak, G., Ofir, A., Oshagh, M., Parviainen, H., Quirrenbach, Andreas, Reffert, S., Reiners, Ansgar, Rodríguez-López, Cristina, Schlecker, M., Stock, S., Trifonov, T., Winn, J.N., Zapatero Osorio, María Rosa, Zechmeister, Mathias, Amado, Pedro J., Anderson, D.R., Batalha, N.E., Bauer, Florian Franz, Bluhm, P., Burke, C.J., Butler, R.P., Caldwell, D.A., Chen, G., Crane, J.D., Dragomir, D., Dressing, C.D., Dynes, S., Jenkins, Jon M., Kaminski, A., Klahr, H., Kotani, T., Lafarga, M., Latham, David W., Lewin, P., McDermott, S., Montañés-Rodríguez, P., Morales, Juan Carlos, Murgas, F., Nagel, Evangelos, Pedraz, S., Ribas, Ignasi, Ricker, G.R., Rowden, P., Seager, S., Shectman, S.A., Tamura, M., Teske, J., Twicken, Joseph D., Vanderspeck, R., Wang, Sharon X., Wohler, Bill, National Aeronautics and Space Administration (US), Max Planck Society, Consejo Superior de Investigaciones Científicas (España), European Commission, Ministerio de Economía y Competitividad (España), German Research Foundation, Klaus Tschira Foundation, Heising Simons Foundation, Ministry of Education, Culture, Sports, Science and Technology (Japan), Japan Society for the Promotion of Science, European Southern Observatory, Luque, R., Pallé, Enric, Kossakowski, D., Dreizler, S., Kemmer, J., Espinoza, Néstor, Burt, J., Anglada-Escudé, Guillem, Béjar, Victor J. S., Caballero, J. A., Collins, Karen A., Collins, KI., Cortés-Contreras, M., Díez-Alonso, E., Feng, Fabo, Hatzes, Artie P., Hellier, C, Henning, Thomas, Jeffers, Sandra V., Kaltenegger, L., Kürster, M., Madden, J., Molaverdikhani, K., Montes, D., Narita, N., Nowak, G., Ofir, A., Oshagh, M., Parviainen, H., Quirrenbach, Andreas, Reffert, S., Reiners, Ansgar, Rodríguez-López, Cristina, Schlecker, M., Stock, S., Trifonov, T., Winn, J.N., Zapatero Osorio, María Rosa, Zechmeister, Mathias, Amado, Pedro J., Anderson, D.R., Batalha, N.E., Bauer, Florian Franz, Bluhm, P., Burke, C.J., Butler, R.P., Caldwell, D.A., Chen, G., Crane, J.D., Dragomir, D., Dressing, C.D., Dynes, S., Jenkins, Jon M., Kaminski, A., Klahr, H., Kotani, T., Lafarga, M., Latham, David W., Lewin, P., McDermott, S., Montañés-Rodríguez, P., Morales, Juan Carlos, Murgas, F., Nagel, Evangelos, Pedraz, S., Ribas, Ignasi, Ricker, G.R., Rowden, P., Seager, S., Shectman, S.A., Tamura, M., Teske, J., Twicken, Joseph D., Vanderspeck, R., Wang, Sharon X., and Wohler, Bill
Abstract: We report the detection of a transiting Earth-size planet around GJ 357, a nearby M2.5 V star, using data from the Transiting Exoplanet Survey Satellite (TESS). GJ 357 b (TOI-562.01) is a transiting, hot, Earth-sized planet (T-eq = 525 +/- 11 K) with a radius of R-b = 1.217 +/- 0.084 R-circle plus and an orbital period of P-b = 3.93 d. Precise stellar radial velocities from CARMENES and PFS, as well as archival data from HIRES, UVES, and HARPS also display a 3.93-day periodicity, confirming the planetary nature and leading to a planetary mass of M-b = 1.84 +/- 0.31 M-circle plus. In addition to the radial velocity signal for GJ 357 b, more periodicities are present in the data indicating the presence of two further planets in the system: GJ 357 c, with a minimum mass of M-c = 3.40 +/- 0.46 M-circle plus in a 9.12 d orbit, and GJ 357 d, with a minimum mass of M-d = 6.1 +/- 1.0 M-circle plus in a 55.7 d orbit inside the habitable zone. The host is relatively inactive and exhibits a photometric rotation period of P-rot = 78 +/- 2 d. GJ 357 b is to date the second closest transiting planet to the Sun, making it a prime target for further investigations such as transmission spectroscopy. Therefore, GJ 357 b represents one of the best terrestrial planets suitable for atmospheric characterization with the upcoming JWST and ground-based ELTs.© ESO 2019
Published: 2019

18. The Close AGN Reference Survey (CARS) Discovery of a global [C II] 158 mu m line excess in AGN HE 1353-1917

Author: German Research Foundation, National Aeronautics and Space Administration (US), European Southern Observatory, Ministerio de Economía y Competitividad (España), European Commission, Smirnova-Pinchukova, I., Husemann, B., Busch, G., Appleton, P., Bethermin, M., Combes, F., Croom, S., Davis, T.A., Fischer, C., Gaspari, M., Groves, B., Klein, R., O'Dea, C.P., Pérez-Torres, Miguel A., Scharwächter, J., Singha, M., Tremblay, G. R., Urrutia, T., German Research Foundation, National Aeronautics and Space Administration (US), European Southern Observatory, Ministerio de Economía y Competitividad (España), European Commission, Smirnova-Pinchukova, I., Husemann, B., Busch, G., Appleton, P., Bethermin, M., Combes, F., Croom, S., Davis, T.A., Fischer, C., Gaspari, M., Groves, B., Klein, R., O'Dea, C.P., Pérez-Torres, Miguel A., Scharwächter, J., Singha, M., Tremblay, G. R., and Urrutia, T.
Abstract: The [C II]lambda 158 mu m line is one of the strongest far-infrared (FIR) lines and an important coolant in the interstellar medium of galaxies that is accessible out to high redshifts. The excitation of [C II] is complex and can best be studied in detail at low redshifts. Here we report the discovery of the highest global [C II] excess with respect to the FIR luminosity in the nearby AGN host galaxy HE 1353-1917. This galaxy is exceptional among a sample of five targets because the AGN ionization cone and radio jet directly intercept the cold galactic disk. As a consequence, a massive multiphase gas outflow on kiloparsec scales is embedded in an extended narrow-line region. Because HE 1353-1917 is distinguished by these special properties from our four bright AGN, we propose that a global [C II] excess in AGN host galaxies could be a direct signature of a multiphase AGN-driven outflow with a high mass-loading factor.© I. Smirnova-Pinchukova et al. 2019
Published: 2019

19. The Close AGN Reference Survey (CARS) A massive multi-phase outflow impacting the edge-on galaxy HE 1353-1917

Author: German Research Foundation, National Aeronautics and Space Administration (US), Australian Research Council, Natural Sciences and Engineering Research Council of Canada, European Southern Observatory, National Science Foundation (US), Korea Astronomy and Space Science Institute, Ministério da Ciência, Tecnologia e Inovação (Brasil), Comisión Nacional de Investigación Científica y Tecnológica (Chile), Max Planck Society, Husemann, B., Scharwachter, J, Davis, T.A., Pérez-Torres, Miguel A., Smirnova-Pinchukova, I, Tremblay, GR, Krumpe, M., Combes, Françoise, Baum, S.A., Busch, G., Connor, Thomas, Croom, S.M., Gaspari, M., Kraft, RP, O'Dea, C.P., Powel, M, Singha, M, Urrutia, T, German Research Foundation, National Aeronautics and Space Administration (US), Australian Research Council, Natural Sciences and Engineering Research Council of Canada, European Southern Observatory, National Science Foundation (US), Korea Astronomy and Space Science Institute, Ministério da Ciência, Tecnologia e Inovação (Brasil), Comisión Nacional de Investigación Científica y Tecnológica (Chile), Max Planck Society, Husemann, B., Scharwachter, J, Davis, T.A., Pérez-Torres, Miguel A., Smirnova-Pinchukova, I, Tremblay, GR, Krumpe, M., Combes, Françoise, Baum, S.A., Busch, G., Connor, Thomas, Croom, S.M., Gaspari, M., Kraft, RP, O'Dea, C.P., Powel, M, Singha, M, and Urrutia, T
Abstract: Context. Galaxy-wide outflows driven by star formation and/or an active galactic nucleus (AGN) are thought to play a crucial rule in the evolution of galaxies and the metal enrichment of the inter-galactic medium. Direct measurements of these processes are still scarce and new observations are needed to reveal the nature of outflows in the majority of the galaxy population. Aims. We combine extensive, spatially-resolved, multi-wavelength observations, taken as part of the Close AGN Reference Survey (CARS), for the edge-on disc galaxy HE 1353-1917 in order to characterise the impact of the AGN on its host galaxy via outflows and radiation. Methods. Multi-color broad-band photometry was combined with spatially-resolved optical, near-infrared (NIR) and sub-mm and radio observations taken with the Multi-Unit Spectroscopy Explorer (MUSE), the Near-infrared Integral Field Spectrometer (NIFS), the Atacama Large Millimeter Array (ALMA), and the Karl G. Jansky Very Large Array (VLA) to map the physical properties and kinematics of the multi-phase interstellar medium. Results. We detect a biconical extended narrow-line region ionised by the luminous AGN orientated nearly parallel to the galaxy disc, extending out to at least 25 kpc. The extra-planar gas originates from galactic fountains initiated by star formation processes in the disc, rather than an AGN outflow, as shown by the kinematics and the metallicity of the gas. Nevertheless, a fast, multi-phase, AGN-driven outflow with speeds up to 1000 km s(-1) is detected close to the nucleus at 1 kpc distance. A radio jet, in connection with the AGN radiation field, is likely responsible for driving the outflow as confirmed by the energetics and the spatial alignment of the jet and multi-phase outflow. Evidence for negative AGN feedback suppressing the star formation rate (SFR) is mild and restricted to the central kpc. But while any SFR suppression must have happened recently, the outflow has the potential to greatly impact th
Published: 2019

20. The evolution of luminous red nova AT 2017jfs in NGC 4470

Author: China Scholarship Council, Science Foundation Ireland, Ministerio de Ciencia e Innovación (España), European Commission, National Science Foundation (US), Istituto Nazionale di Astrofisica, Science and Technology Facilities Council (UK), European Research Council, European Southern Observatory, Lomonosov Moscow State University, Pastorello, Andrea, Chen, T. W., Cai, Yongzhi, Morales-Garoffolo, A., Cano, Z., Mason, E., Barsukova, E. A., Benetti, S., Berton, M., Bose, S., Bufano, F., Callis, E., Cannizzaro, G., Cartier, R., Chen, P., Dong, S. B., Dyrbye, S., Elias-Rosa, Nancy, Flors, A., Fraser, Morgan, Geier, Stefan, Goranskij, V. P., Kann, D. A., Kuncarayakti, Hanindyo, Onori, F., Reguitti, Andrea, Reynolds, Thomas M., Losada, I. R., Carracedo, A. S., Schweyer, T., Smartt, S. J., Tatarnikov, A. M., Valeev, A. F., Vogl, Christian, Wevers, T., Ugarte Postigo, Antonio de, Izzo, L., Inserra, Cosimo, Kankare, E, Maguire, Kate, Smith, Ken W., Stalder, B., Tartaglia, Leonardo, Thöne, Cristina Carina, Valerin, Giorgio, Young, D. R., China Scholarship Council, Science Foundation Ireland, Ministerio de Ciencia e Innovación (España), European Commission, National Science Foundation (US), Istituto Nazionale di Astrofisica, Science and Technology Facilities Council (UK), European Research Council, European Southern Observatory, Lomonosov Moscow State University, Pastorello, Andrea, Chen, T. W., Cai, Yongzhi, Morales-Garoffolo, A., Cano, Z., Mason, E., Barsukova, E. A., Benetti, S., Berton, M., Bose, S., Bufano, F., Callis, E., Cannizzaro, G., Cartier, R., Chen, P., Dong, S. B., Dyrbye, S., Elias-Rosa, Nancy, Flors, A., Fraser, Morgan, Geier, Stefan, Goranskij, V. P., Kann, D. A., Kuncarayakti, Hanindyo, Onori, F., Reguitti, Andrea, Reynolds, Thomas M., Losada, I. R., Carracedo, A. S., Schweyer, T., Smartt, S. J., Tatarnikov, A. M., Valeev, A. F., Vogl, Christian, Wevers, T., Ugarte Postigo, Antonio de, Izzo, L., Inserra, Cosimo, Kankare, E, Maguire, Kate, Smith, Ken W., Stalder, B., Tartaglia, Leonardo, Thöne, Cristina Carina, Valerin, Giorgio, and Young, D. R.
Abstract: We present the results of our photometric and spectroscopic follow-up of the intermediate-luminosity optical transient AT 2017jfs. At peak, the object reaches an absolute magnitude of Mg = -15:46 ± 0:15 mag and a bolometric luminosity of 5:5 × 1041 erg s-1. Its light curve has the doublepeak shape typical of luminous red novae (LRNe), with a narrow first peak bright in the blue bands, while the second peak is longer-lasting and more luminous in the red and near-infrared (NIR) bands. During the first peak, the spectrum shows a blue continuum with narrow emission lines of H and Fe II. During the second peak, the spectrum becomes cooler, resembling that of a K-type star, and the emission lines are replaced by a forest of narrow lines in absorption. About 5 months later, while the optical light curves are characterized by a fast linear decline, the NIR ones show a moderate rebrightening, observed until the transient disappears in solar conjunction. At these late epochs, the spectrum becomes reminiscent of that of M-type stars, with prominent molecular absorption bands. The late-time properties suggest the formation of some dust in the expanding common envelope or an IR echo from foreground pre-existing dust. We propose that the object is a common-envelope transient, possibly the outcome of a merging event in a massive binary, similar to NGC4490-2011OT1. © ESO 2019.
Published: 2019

21. A luminous stellar outburst during a long-lasting eruptive phase first, and then SN IIn 2018cnf

Author: National Science Foundation (US), National Natural Science Foundation of China, Chinese Academy of Sciences, National Science Centre (Poland), Science Foundation Ireland, European Commission, European Research Council, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), National Aeronautics and Space Administration (US), Science and Technology Facilities Council (UK), Gordon and Betty Moore Foundation, Villum Fonden, The Ohio State University, European Southern Observatory, Pastorello, Andrea, Reguitti, Andrea, Morales-Garoffolo, A., Cano, Z., Prentice, S.J., Hiramatsu, Daichi, Burke, J., Kankare, E., Kotak, R., Reynolds, T., Smartt, S. J., Bose, S., Chen, P., Congiu, E., Dong, S., Geier, S., Gromadzki, M., Hsiao, E. Y., Kumar, Sumit, Ochner, P., Pignata, Giuliano, Tomasella, L., Wang, L., Arcavi, I., Ashall, Chris, Callis, E., Ugarte Postigo, Antonio de, Fraser, Morgan, Hosseinzadeh, Griffin, Howell, D. A., Inserra, Cosimo, Kann, D.A., Mason, E., Mazzali, Paolo A., McCully, C., Rodríguez, O., Phillips, M. M., Smith, Ken W., Tartaglia, Leonardo, Thöne, Cristina Carina, Wevers, T., Young, D. R., Pumo, M. L., Lowe, T. B., Magnier, E. A., Wainscoat, R. J., Waters, C., Wright, D. E., National Science Foundation (US), National Natural Science Foundation of China, Chinese Academy of Sciences, National Science Centre (Poland), Science Foundation Ireland, European Commission, European Research Council, Ministerio de Economía y Competitividad (España), Ministerio de Ciencia, Innovación y Universidades (España), National Aeronautics and Space Administration (US), Science and Technology Facilities Council (UK), Gordon and Betty Moore Foundation, Villum Fonden, The Ohio State University, European Southern Observatory, Pastorello, Andrea, Reguitti, Andrea, Morales-Garoffolo, A., Cano, Z., Prentice, S.J., Hiramatsu, Daichi, Burke, J., Kankare, E., Kotak, R., Reynolds, T., Smartt, S. J., Bose, S., Chen, P., Congiu, E., Dong, S., Geier, S., Gromadzki, M., Hsiao, E. Y., Kumar, Sumit, Ochner, P., Pignata, Giuliano, Tomasella, L., Wang, L., Arcavi, I., Ashall, Chris, Callis, E., Ugarte Postigo, Antonio de, Fraser, Morgan, Hosseinzadeh, Griffin, Howell, D. A., Inserra, Cosimo, Kann, D.A., Mason, E., Mazzali, Paolo A., McCully, C., Rodríguez, O., Phillips, M. M., Smith, Ken W., Tartaglia, Leonardo, Thöne, Cristina Carina, Wevers, T., Young, D. R., Pumo, M. L., Lowe, T. B., Magnier, E. A., Wainscoat, R. J., Waters, C., and Wright, D. E.
Abstract: We present the results of the monitoring campaign of the Type IIn supernova (SN) 2018cnf (a.k.a. ASASSN-18mr). It was discovered about ten days before the maximum light (on MJD = 58 293.4 ± 5.7 in the V band, with MV = ?18.13 ± 0.15 mag). The multiband light curves show an immediate post-peak decline with some minor luminosity fluctuations, followed by a flattening starting about 40 days after maximum. The early spectra are relatively blue and show narrow Balmer lines with P Cygni profiles. Additionally, Fe II, O I, He I, and Ca II are detected. The spectra show little evolution with time and with intermediate-width features becoming progressively more prominent, indicating stronger interaction of the SN ejecta with the circumstellar medium. The inspection of archival images from the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) survey has revealed a variable source at the SN position with a brightest detection in December 2015 at Mr = ?14.66 ± 0.17 mag. This was likely an eruptive phase from the massive progenitor star that started from at least mid-2011, and that produced the circumstellar environment within which the star exploded as a Type IIn SN. The overall properties of SN 2018cnf closely resemble those of transients such as SN 2009ip. This similarity favours a massive hypergiant, perhaps a luminous blue variable, as progenitor for SN 2018cnf. © ESO 2019
Published: 2019

22. The delay of shock breakout due to circumstellar material evident in most type II supernovae

Author: Ministry of Education, Culture, Sports, Science and Technology (Japan), Comisión Nacional de Investigación Científica y Tecnológica (Chile), Ministerio de Economía, Fomento y Turismo (Chile), Korea Astronomy and Space Science Institute, National Science Foundation (US), German Research Foundation, European Research Council, Science Foundation Ireland, Russian Science Foundation, European Southern Observatory, Förster, Francisco, Moriya, T. J., Maureira, J. C., Anderson, Joseph P., Blinnikov, S., Bufano, F., Cabrera-Vives, G., Clocchiatti, A., de Jaeger, T., Estévez, P. A., Galbany, Lluís, González-Gaitán, Santiago, Gräfener, G., Hamuy, M., Hsiao, E. Y., Huentelemu, P., Huijse, P., Kuncarayakti, Hanindyo, Martínez, J., Medina, G., Olivares E., F., Pignata, Giuliano, Razza, A., Reyes, I., San Martín, J., Smith, R. C., Vera, E., Vivas, A. K., de Ugarte Postigo, Antonio de, Yoon, S. -C., Ashall, Chris, Fraser, Morgan, Gal-Yam, Avishay, Kankare, E., Le Guillou, Laurent, Mazzali, Paolo A., Walton, N. A., Young, D. R., Ministry of Education, Culture, Sports, Science and Technology (Japan), Comisión Nacional de Investigación Científica y Tecnológica (Chile), Ministerio de Economía, Fomento y Turismo (Chile), Korea Astronomy and Space Science Institute, National Science Foundation (US), German Research Foundation, European Research Council, Science Foundation Ireland, Russian Science Foundation, European Southern Observatory, Förster, Francisco, Moriya, T. J., Maureira, J. C., Anderson, Joseph P., Blinnikov, S., Bufano, F., Cabrera-Vives, G., Clocchiatti, A., de Jaeger, T., Estévez, P. A., Galbany, Lluís, González-Gaitán, Santiago, Gräfener, G., Hamuy, M., Hsiao, E. Y., Huentelemu, P., Huijse, P., Kuncarayakti, Hanindyo, Martínez, J., Medina, G., Olivares E., F., Pignata, Giuliano, Razza, A., Reyes, I., San Martín, J., Smith, R. C., Vera, E., Vivas, A. K., de Ugarte Postigo, Antonio de, Yoon, S. -C., Ashall, Chris, Fraser, Morgan, Gal-Yam, Avishay, Kankare, E., Le Guillou, Laurent, Mazzali, Paolo A., Walton, N. A., and Young, D. R.
Abstract: Type II supernovae (SNe II) originate from the explosion of hydrogen-rich supergiant massive stars. Their first electromagnetic signature is the shock breakout (SBO), a short-lived phenomenon that can last for hours to days depending on the density at shock emergence. We present 26 rising optical light curves of SN II candidates discovered shortly after explosion by the High Cadence Transient Survey and derive physical parameters based on hydrodynamical models using a Bayesian approach. We observe a steep rise of a few days in 24 out of 26 SN II candidates, indicating the systematic detection of SBOs in a dense circumstellar matter consistent with a mass loss rate of Ṁ> 10M yr or a dense atmosphere. This implies that the characteristic hour-timescale signature of stellar envelope SBOs may be rare in nature and could be delayed into longer-lived circumstellar material SBOs in most SNe II. © 2018, Nature Publishing Group. All rights reserved.
Published: 2018

23. The Castalia mission to Main Belt Comet 133P/Elst-Pizarro

Author: Science and Technology Facilities Council (UK), European Southern Observatory, Snodgrass, C., Jones, G. H., Boehnhardt, H., Gibbings, A., Homeister, M., Andre, N., Beck, P., Bentley, M. S., Bertini, I., Bowles, Neil, Capria, M. T., Carr, C., Ceriotti, M., Coates, A. J., Della Corte, V., Donaldson Hanna, K. L., Fitzsimmons, A., Gutiérrez, Pedro J., Hainaut, O. R., Herique, A., Hilchenbach, M., Hsieh, H. H., Jehin, E., Karatekin, O., Kofman, W., Lara, Luisa María, Laudan, K., Licandro, J., Lowry, S. C., Marzari, F., Masters, A., Meech, K. J., Moreno, Fernando, Morse, A., Orosei, R., Pack, A., Plettemeier, D., Prialnik, D., Rotundi, A., Rubin, M., Sánchez, J. P., Sheridan, S., Trieloff, M., Winterboer, A., Science and Technology Facilities Council (UK), European Southern Observatory, Snodgrass, C., Jones, G. H., Boehnhardt, H., Gibbings, A., Homeister, M., Andre, N., Beck, P., Bentley, M. S., Bertini, I., Bowles, Neil, Capria, M. T., Carr, C., Ceriotti, M., Coates, A. J., Della Corte, V., Donaldson Hanna, K. L., Fitzsimmons, A., Gutiérrez, Pedro J., Hainaut, O. R., Herique, A., Hilchenbach, M., Hsieh, H. H., Jehin, E., Karatekin, O., Kofman, W., Lara, Luisa María, Laudan, K., Licandro, J., Lowry, S. C., Marzari, F., Masters, A., Meech, K. J., Moreno, Fernando, Morse, A., Orosei, R., Pack, A., Plettemeier, D., Prialnik, D., Rotundi, A., Rubin, M., Sánchez, J. P., Sheridan, S., Trieloff, M., and Winterboer, A.
Abstract: We describe Castalia, a proposed mission to rendezvous with a Main Belt Comet (MBC), 133P/Elst-Pizarro. MBCs are a recently discovered population of apparently icy bodies within the main asteroid belt between Mars and Jupiter, which may represent the remnants of the population which supplied the early Earth with water. Castalia will perform the first exploration of this population by characterising 133P in detail, solving the puzzle of the MBC's activity, and making the first in situ measurements of water in the asteroid belt. In many ways a successor to ESA's highly successful Rosetta mission, Castalia will allow direct comparison between very different classes of comet, including measuring critical isotope ratios, plasma and dust properties. It will also feature the first radar system to visit a minor body, mapping the ice in the interior. Castalia was proposed, in slightly different versions, to the ESA M4 and M5 calls within the Cosmic Vision programme. We describe the science motivation for the mission, the measurements required to achieve the scientific goals, and the proposed instrument payload and spacecraft to achieve these. © 2017 COSPAR
Published: 2018

24. Chromospheric Heating due to Cancellation of Quiet Sun Internetwork Fields

Author: European Southern Observatory, Norwegian Space Agency, National Aeronautics and Space Administration (US), Swedish Research Council, Swedish National Space Board, Swedish Civil Contingencies Agency, European Research Council, Ministerio de Economía y Competitividad (España), European Commission, Research Council of Norway, Gošić, M., de la Cruz Rodríguez, J., De Pontieu, Bart, Bellot Rubio, Luis R., Carlsson, M., Esteban Pozuelo, Sara, Ortiz, A., Polito, Vanessa, European Southern Observatory, Norwegian Space Agency, National Aeronautics and Space Administration (US), Swedish Research Council, Swedish National Space Board, Swedish Civil Contingencies Agency, European Research Council, Ministerio de Economía y Competitividad (España), European Commission, Research Council of Norway, Gošić, M., de la Cruz Rodríguez, J., De Pontieu, Bart, Bellot Rubio, Luis R., Carlsson, M., Esteban Pozuelo, Sara, Ortiz, A., and Polito, Vanessa
Abstract: The heating of the solar chromosphere remains one of the most important questions in solar physics. Our current understanding is that small-scale internetwork (IN) magnetic fields play an important role as a heating agent. Indeed, cancellations of IN magnetic elements in the photosphere can produce transient brightenings in the chromosphere and transition region. These bright structures might be the signature of energy release and plasma heating, probably driven by the magnetic reconnection of IN field lines. Although single events are not expected to release large amounts of energy, their global contribution to the chromosphere may be significant due to their ubiquitous presence in quiet Sun regions. In this paper, we study cancellations of IN elements and analyze their impact on the energetics and dynamics of the quiet Sun atmosphere. We use high-resolution, multiwavelength, coordinated observations obtained with the Interface Region Imaging Spectrograph and the Swedish 1 m Solar Telescope (SST) to identify cancellations of IN magnetic flux patches and follow their evolution. We find that, on average, these events live for ∼3 minutes in the photosphere and ∼12 minutes in the chromosphere and/or transition region. Employing multi-line inversions of the Mg ii h and k lines, we show that cancellations produce clear signatures of heating in the upper atmospheric layers. However, at the resolution and sensitivity accessible to the SST, their number density still seems to be one order of magnitude too low to explain the global chromospheric heating.© 2018. The American Astronomical Society. All rights reserved.
Published: 2018

25. The Gaia-ESO Survey: Churning through the Milky Way

Author: Agence Nationale de la Recherche (France), Knut and Alice Wallenberg Foundation, European Southern Observatory, Science and Technology Facilities Council (UK), European Research Council, Leverhulme Trust, Istituto Nazionale di Astrofisica, Ministero dell'Istruzione, dell'Università e della Ricerca, European Science Foundation, Hayden, M.R., Recio-Blanco, A., de Laverny, P., Mikolaitis, S., Guiglion, Guillaume, Hill, V., Gilmore, Gerry, Randich, S., Bayo, A., Bensby, T., Bergemann, Maria, Bragaglia, A., Casey, A., Costado, M. T., Feltzing, S., Franciosini, E., Hourihane, A., Jofré, P., Koposov, S., Kordopatis, G., Lanzafame, A., Lardo, C., Lewis, J., Lind, K., Magrini, L., Monaco, L., Morbidelli, L., Pancino, E., Sacco, G., Stonkute, E., Worley, C.C., Zwitter, T., Agence Nationale de la Recherche (France), Knut and Alice Wallenberg Foundation, European Southern Observatory, Science and Technology Facilities Council (UK), European Research Council, Leverhulme Trust, Istituto Nazionale di Astrofisica, Ministero dell'Istruzione, dell'Università e della Ricerca, European Science Foundation, Hayden, M.R., Recio-Blanco, A., de Laverny, P., Mikolaitis, S., Guiglion, Guillaume, Hill, V., Gilmore, Gerry, Randich, S., Bayo, A., Bensby, T., Bergemann, Maria, Bragaglia, A., Casey, A., Costado, M. T., Feltzing, S., Franciosini, E., Hourihane, A., Jofré, P., Koposov, S., Kordopatis, G., Lanzafame, A., Lardo, C., Lewis, J., Lind, K., Magrini, L., Monaco, L., Morbidelli, L., Pancino, E., Sacco, G., Stonkute, E., Worley, C.C., and Zwitter, T.
Abstract: Context. There have been conflicting results with respect to the extent that radial migration has played in the evolution of the Galaxy. Additionally, observations of the solar neighborhood have shown evidence of a merger in the past history of the Milky Way that drives enhanced radial migration. Aims. We attempt to determine the relative fraction of stars that have undergone significant radial migration by studying the orbital properties of metal-rich ([Fe/H] > 0.1) stars within 2 kpc of the Sun. We also aim to investigate the kinematic properties, such as velocity dispersion and orbital parameters, of stellar populations near the Sun as a function of [Mg/Fe] and [Fe/H], which could show evidence of a major merger in the past history of the Milky Way. Methods. We used a sample of more than 3000 stars selected from the fourth internal data release of the Gaia-ESO Survey. We used the stellar parameters from the Gaia-ESO Survey along with proper motions from PPMXL to determine distances, kinematics, and orbital properties for these stars to analyze the chemodynamic properties of stellar populations near the Sun. Results. Analyzing the kinematics of the most metal-rich stars ([Fe/H] > 0.1), we find that more than half have small eccentricities (e< 0.2) or are on nearly circular orbits. Slightly more than 20% of the metal-rich stars have perigalacticons R> 7 kpc. We find that the highest [Mg/Fe], metal-poor populations have lower vertical and radial velocity dispersions compared to lower [Mg/Fe] populations of similar metallicity by ~10 km s. The median eccentricity increases linearly with [Mg/Fe] across all metallicities, while the perigalacticon decreases with increasing [Mg/Fe] for all metallicities. Finally, the most [Mg/Fe]-rich stars are found to have significant asymmetric drift and rotate more than 40 km s slower than stars with lower [Mg/Fe] ratios. Conclusions. While our results cannot constrain how far stars have migrated, we propose that migration processes
Published: 2018

26. The Gaia-ESO Survey: open clusters in Gaia-DR1. A way forward to stellar age calibration

Author: European Southern Observatory, Science and Technology Facilities Council (UK), Robert Martin Ayers Sciences Fund, European Commission, Leverhulme Trust, Istituto Nazionale di Astrofisica, Ministero dell'Istruzione, dell'Università e della Ricerca, Ministerio de Economía y Competitividad (España), Swedish National Space Board, Randich, S., Tognelli, E., Jackson, R., Jeffries, R.D., Degl'Innocenti, S., Pancino, E., Re Fiorentin, P., Spagna, A., Sacco, G., Bragaglia, A., Magrini, L., Prada Moroni, P. G., Alfaro, Emilio J., Franciosini, E., Morbidelli, L., Roccatagliata, V., Bouy, Hervé, Bravi, L., Jiménez-Esteban, Francisco M., Jordi, Carme, Zari, E., Tautvaišienė, G., Drazdauskas, A., Mikolaitis, S., Gilmore, Gerry, Feltzing, S., Vallenari, A., Bensby, T., Koposov, S., Korn, A., Lanzafame, A., Smiljanic, R., Bayo, A., Carraro, G., Costado, M. T., Heiter, Ulrike, Hourihane, A., Jofré, P., Lewis, J., Monaco, L., Prisinzano, L., Sbordone, L., Sousa, S. G., Worley, C. C., Zaggia, S., European Southern Observatory, Science and Technology Facilities Council (UK), Robert Martin Ayers Sciences Fund, European Commission, Leverhulme Trust, Istituto Nazionale di Astrofisica, Ministero dell'Istruzione, dell'Università e della Ricerca, Ministerio de Economía y Competitividad (España), Swedish National Space Board, Randich, S., Tognelli, E., Jackson, R., Jeffries, R.D., Degl'Innocenti, S., Pancino, E., Re Fiorentin, P., Spagna, A., Sacco, G., Bragaglia, A., Magrini, L., Prada Moroni, P. G., Alfaro, Emilio J., Franciosini, E., Morbidelli, L., Roccatagliata, V., Bouy, Hervé, Bravi, L., Jiménez-Esteban, Francisco M., Jordi, Carme, Zari, E., Tautvaišienė, G., Drazdauskas, A., Mikolaitis, S., Gilmore, Gerry, Feltzing, S., Vallenari, A., Bensby, T., Koposov, S., Korn, A., Lanzafame, A., Smiljanic, R., Bayo, A., Carraro, G., Costado, M. T., Heiter, Ulrike, Hourihane, A., Jofré, P., Lewis, J., Monaco, L., Prisinzano, L., Sbordone, L., Sousa, S. G., Worley, C. C., and Zaggia, S.
Abstract: Context. Determination and calibration of the ages of stars, which heavily rely on stellar evolutionary models, are very challenging, while representing a crucial aspect in many astrophysical areas. Aims. We describe the methodologies that, taking advantage of Gaia-DR1 and the Gaia-ESO Survey data, enable the comparison of observed open star cluster sequences with stellar evolutionary models. The final, long-term goal is the exploitation of open clusters as age calibrators. Methods. We perform a homogeneous analysis of eight open clusters using the Gaia-DR1 TGAS catalogue for bright members and information from the Gaia-ESO Survey for fainter stars. Cluster membership probabilities for the Gaia-ESO Survey targets are derived based on several spectroscopic tracers. The Gaia-ESO Survey also provides the cluster chemical composition. We obtain cluster parallaxes using two methods. The first one relies on the astrometric selection of a sample of bona fide members, while the other one fits the parallax distribution of a larger sample of TGAS sources. Ages and reddening values are recovered through a Bayesian analysis using the 2MASS magnitudes and three sets of standard models. Lithium depletion boundary (LDB) ages are also determined using literature observations and the same models employed for the Bayesian analysis. Results. For all but one cluster, parallaxes derived by us agree with those presented in Gaia Collaboration (2017, A&A, 601, A19), while a discrepancy is found for NGC 2516; we provide evidence supporting our own determination. Inferred cluster ages are robust against models and are generally consistent with literature values. Conclusions. The systematic parallax errors inherent in the Gaia DR1 data presently limit the precision of our results. Nevertheless, we have been able to place these eight clusters onto the same age scale for the first time, with good agreement between isochronal and LDB ages where there is overlap. Our approach appears promising an
Published: 2018

27. Replication data for: Deep 3.8 Micron Observations of the Trapezium Cluster

Author: Muench, August (Harvard-Smithsonian Center For Astrophysics, 60 Garden Street, Cambridge, MA 02138), Alves, Joao (European Southern Observatory, Karl-Schwartzschild-Strasse 2, D-85748 Garching, Germany), Lada, Charles (Harvard-Smithsonian Center For Astrophysics, 60 Garden Street, Cambridge, MA 02138), and Lada, Elizabeth (Department Of Astronomy, University Of Florida, P.O. Box 112055, Gainesville, FL 32611)
Published: 2015
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28. The exceptional Herbig Ae star HD 101412: The first detection of resolved magnetically split lines and the presence of chemical spots in a Herbig star

Author: Department of Astronomy, University of Michigan, Ann Arbor, MI 48109-1042, USA, European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching bei MÜnchen, Germany, Institute of Astronomy, Russian Academy of Sciences, Pyatnitskaya 48, Moscow 119017, Russia, Instituto de Ciencias Astronomicas, de la Tierra, y del Espacio (ICATE), 5400 San Juan, Argentina, European Southern Observatory, Alonso de Cordova 3107, Casilla 19001, Santiago 19, Chile, Astrophysikalisches Institut Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany, Schöller, M., Savanov, I., Gonzälez, J. F., Cowley, Charles R., Schütz, O., Arlt, R., Rüdiger, G., Department of Astronomy, University of Michigan, Ann Arbor, MI 48109-1042, USA, European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching bei MÜnchen, Germany, Institute of Astronomy, Russian Academy of Sciences, Pyatnitskaya 48, Moscow 119017, Russia, Instituto de Ciencias Astronomicas, de la Tierra, y del Espacio (ICATE), 5400 San Juan, Argentina, European Southern Observatory, Alonso de Cordova 3107, Casilla 19001, Santiago 19, Chile, Astrophysikalisches Institut Potsdam, An der Sternwarte 16, 14482 Potsdam, Germany, Schöller, M., Savanov, I., Gonzälez, J. F., Cowley, Charles R., Schütz, O., Arlt, R., and Rüdiger, G.
Abstract: In our previous search for magnetic fields in Herbig Ae stars, we pointed out that HD 101412 possesses the strongest magnetic field among the Herbig Ae stars and hence is of special interest for follow-up studies of magnetism among young pre-main-sequence stars. We obtained high-resolution, high signal-to-noise UVES and a few lower quality HARPS spectra revealing the presence of resolved magnetically split lines. HD 101412 is the first Herbig Ae star for which the rotational Doppler effect was found to be small in comparison to the magnetic splitting and several spectral lines observed in unpolarized light at high dispersion are resolved into magnetically split components. The measured mean magnetic field modulus varies from 2.5 to 3.5kG, while the mean quadratic field was found to vary in the range of 3.5 to 4.8 kG. To determine the period of variations, we used radial velocity, equivalent width, line width, and line asymmetry measurements of variable spectral lines of several elements, as well as magnetic field measurements. The period determination was done using the Lomb-Scargle method. The most pronounced variability was detected for spectral lines of He I and the iron peak elements, whereas the spectral lines of CNO elements are only slightly variable. From spectral variations and magnetic field measurements we derived a potential rotation period P rot = 13.86 d, which has to be proven in future studies with a larger number of observations. It is the first time that the presence of element spots is detected on the surface of a Herbig Ae/Be star. Our previous study of Herbig Ae stars revealed a trend towards stronger magnetic fields for younger Herbig Ae stars, confirmed by statistical tests. This is in contrast to a few other (non-statistical) studies claiming that magnetic Herbig Ae stars are progenitors of the magnetic Ap stars. New developments in MHD theory show that the measured magnetic field strengths are compatible with a current-driven instability of
Published: 2010

29. W51 Densitometry

Author: Adam Ginsburg (European Southern Observatory)
Published: 2014
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30. J, H, K Spectro-Interferometry of the Mira Variable S Orionis

Author: EUROPEAN SOUTHERN OBSERVATORY MUENCHEN (GERMANY), Wittkowski, M., Boboltz, D. A., Driebe, T., Le Bouquin, J., Millour, F., Ohnaka, K., Scholz, M., EUROPEAN SOUTHERN OBSERVATORY MUENCHEN (GERMANY), Wittkowski, M., Boboltz, D. A., Driebe, T., Le Bouquin, J., Millour, F., Ohnaka, K., and Scholz, M.
Abstract: We present J, H, K spectrally dispersed interferometry with a spectral resolution of 35 for the Mira variable S Orionis. We aim at measuring diameter variation as a function of wavelength that is expected due to molecular layers lying above the continuum-forming photosphere. Our final goal is a better understanding of the pulsating atmosphere and its role in the mass-loss process. Visibility data of S Ori were obtained at phase 0.78 with the VLTI/AMBER instrument. Apparent uniform disk (UD) diameters were computed for each spectral channel. In addition, the visibility data were directly compared to predictions by recent self-excited dynamic model atmospheres. S Ori shows significant variations in the visibility values as a function of spectral channel that can only be described by a clear variation in the apparent angular size with wavelength. The closure phase values are close to zero at all spectral channels, indicating the absence of asymmetric intensity features. The apparent UD angular diameter is smallest at about 1.3 microns and 1.7 microns and increases by a factor of approximately 1.4 around 2.0 microns. The minimum UD angular diameter at near-continuum wavelengths is ThetaUD = 8.1 +/- 0.5 mas, corresponding to R approximately equal to 420 Rsolar. The S Ori visibility data and the apparent UD variations can be explained reasonably well by a dynamic atmosphere model that includes molecular layers, particularly water vapor and CO. The best-fitting photospheric angular diameter of the model atmosphere is ThetaPhot = 8.3 +/- 0.2 mas, consistent with the UD diameter measured at near-continuum wavelengths. The measured visibility and UD diameter variations with wavelength resemble and generally confirm the predictions by recent dynamic model atmospheres. These size variations with wavelength can be understood as the effects from water vapor and CO layers lying above the continuum-forming photosphere., Prepared in collaboration with US Naval Observatory, Washington, DC; Max-Planck-Institut fur Radioastronomie, Bonn, Germany; European Southern Observatory (ESO), Santiago, Chile; Institut fur Theoretische Astrophysik der Univ. Heidelberg, Heidelberg, Germany; and Institute of Astronomy, University of Sydney, Sydney, Australia. Published in Astronomy & Astrophysics, v479, L21-L24, 2008.
Published: 2008

31. The Mira Variable S Orionis: Relationships Between the Photosphere, Molecular Layer, Dust Shell, and SiO Maser Shell at 4 Epochs

Author: EUROPEAN SOUTHERN OBSERVATORY MUENCHEN (GERMANY), Wittkowski, M., Boboltz, D. A., Ohnaka, K., Driebe, T., Scholz, M., EUROPEAN SOUTHERN OBSERVATORY MUENCHEN (GERMANY), Wittkowski, M., Boboltz, D. A., Ohnaka, K., Driebe, T., and Scholz, M.
Abstract: We present the first multi-epoch study that includes concurrent mid-infrared and radio interferometry of an oxygen-rich Mira star. We obtained mid-infrared interferometry of S Ori with VLTI/MIDI at four epochs. We concurrently observed v = 1, J = 1-0 (43.1GHz), and v = 2, J = 1-0 (42.8GHz) SiO maser emission toward S Ori with the VLBA in January, February, and November 2005. The MIDI data are analyzed using self-excited dynamic model atmospheres including molecular layers, complemented by a radiative transfer model of the circumstellar dust shell. The VLBA data are reduced to the spatial structure and kinematics of the maser spots. The modeling of our MIDI data results in phase-dependent continuum photospheric angular diameters. The dust shell can best be modeled with Al2O3 grains using phase-dependent inner boundary radii between 1.8 and 2.4 photospheric radii. The dust shell appears to be more compact with greater optical depth near visual minimum, and more extended with lower optical depth after visual maximum. The maser spots mark the region of the molecular atmospheric layers just beyond the steepest decrease in the mid-infrared model intensity profile. Their velocity structure indicates a radial gas expansion. S Ori shows significant phase-dependences of photospheric radii and dust shell parameters. Al2O3 dust grains and SiO maser spots form at relatively small radii of <1.8 2.4 photospheric radii. Our results suggest increased mass loss and dust formation close to the surface near the minimum visual phase, when Al2O3 dust grains are co-located with the molecular gas and the SiO maser shells, and a more expanded dust shell after visual maximum. Silicon does not appear to be bound in dust, as our data show no sign of silicate grains., Prepared in collaboration with the Max-Planck-Institut fur Radioastronomie, Bonn, Germany; Institut fr Theoretische Astrophysik der Univ. Heidelberg, Germany; and the Institute of Astronomy, University of Sydney, Australia. Published in Astronomy & Astrophysics, v470, p191-210, 2007. The original document contains color images.
Published: 2007

32. Europe reaches for the stars : forty years ESO, 1962-2002

Author: European Southern Observatory Education and Public Relations Department. and European Southern Observatory Education and Public Relations Department.
Abstract: "Celebrating ESO's 40th Anniversary, this film sets out to trace the evolution of ESO, from the humble beginnings until today, where ESO operates the most powerful optical telescope on Earth, the VLT"--Contain back cover., Title from contain label., Produced by the ESO Education and Public Relations Dept., DVD., Englsh, French and German.

33. New Generation Stellar Spectral Libraries in the Optical and Near-infrared. I. The Recalibrated UVES-POP Library for Stellar Population Synthesis

Author: Sviatoslav B. Borisov, Igor V. Chilingarian, Evgenii V. Rubtsov, Cédric Ledoux, Claudio Melo, Kirill A. Grishin, Ivan Yu. Katkov, Vladimir S. Goradzhanov, Anton V. Afanasiev, Anastasia V. Kasparova, Anna S. Saburova, Université de Genève = University of Geneva (UNIGE), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Sternberg Astronomical Institute [Moscow], Lomonosov Moscow State University (MSU), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Portuguese Space Agency, AstroParticule et Cosmologie (APC (UMR_7164)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Abu Dhabi University (ADU), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)
Subjects: Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics - Astrophysics of Galaxies, Solar and Stellar Astrophysics (astro-ph.SR)
Abstract: We present re-processed flux calibrated spectra of 406 stars from the UVES-POP stellar library in the wavelength range 320-1025 nm, which can be used for stellar population synthesis. The spectra are provided in the two versions having spectral resolving power R=20,000 and R=80,000. Raw spectra from the ESO data archive were re-reduced using the latest version of the UVES data reduction pipeline with some additional algorithms that we developed. The most significant improvements in comparison with the original UVES-POP release are: (i) an updated Echelle order merging, which eliminates "ripples" present in the published spectra, (ii) a full telluric correction, (iii) merging of non-overlapping UVES spectral setups taking into account the global continuum shape, (iv) a spectrophotometric correction and absolute flux calibration, and (v) estimates of the interstellar extinction. For 364 stars from our sample, we computed atmospheric parameters $T_\mathrm{eff}$, surface gravity log $g$, metallicity [Fe/H], and $\alpha$-element enhancement [$\alpha$/Fe] by using a full spectrum fitting technique based on a grid of synthetic stellar atmospheres and a novel minimization algorithm. We also provide projected rotational velocity $v\sin i$ and radial velocity $v_{rad}$ estimates. The overall absolute flux uncertainty in the re-processed dataset is better than 2% with sub-% accuracy for about half of the stars. A comparison of the recalibrated UVES-POP spectra with other spectral libraries shows a very good agreement in flux; at the same time, $Gaia$ DR3 BP/RP spectra are often discrepant with our data, which we attribute to spectrophotometric calibration issues in $Gaia$ DR3., Comment: 26 pages, 19 figures, accepted for publication in ApJS
Published: 2023

34. Connecting SPHERE and CRIRES+ for the characterisation of young exoplanets at high spectral resolution: status update of VLT/HiRISE

Author: Arthur Vigan, Maxime Lopez, Mona El Morsy, Eduard R. Muslimov, Alexandre Viret, Gérard Zins, Graham J. Murray, Anne Costille, Gilles P. P. L. Otten, Ulf Seemann, Heiko Anwand-Heerwart, Kjetil Dohlen, Patrick Blanchard, José Garcia, Yannick Charles, Nicolas Tchoubaklian, Timothé Ely, Mark Phillips, Jérôme Paufique, Jean-Luc Beuzit, Mathis Houllé, Jean Costes, Raphaël Pourcelot, Isabelle Baraffe, Reinhold Dorn, Marc Jaquet, Markus Kasper, Ansgar Reiners, Alain Smette, Leonardo Blanco, Laurent Pallanca, Alexis Carlotti, Elodie Choquet, David Mouillet, Mamadou N'Diaye, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Universidad ORT Uruguay, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Université Côte d'Azur - École universitaire de recherche Odyssée - Sciences de la société et de l'environnement (UCA EUR SSE), and Université Côte d'Azur (UCA)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), High-dispersion coronagraphy, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Characterisation, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Exoplanet, VLT, High-contrast imaging, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Spectroscopy, Astrophysics::Galaxy Astrophysics, High-spectral resolution, Astrophysics - Earth and Planetary Astrophysics
Abstract: New generation exoplanet imagers on large ground-based telescopes are highly optimised for the detection of young giant exoplanets in the near-infrared, but they are intrinsically limited for their characterisation by the low spectral resolution of their integral field spectrographs ($R, Submitted to SPIE Astronomical Telescopes + Instrumentation 2022, Adaptive Optics Systems VIII, Paper 12185-27
Published: 2022

35. A dusty veil shading Betelgeuse during its Great Dimming

Author: Stefan Kraus, Eric Lagadec, E. Cannon, Florentin Millour, Guy Perrin, A. de Koter, John D. Monnier, Andrea Chiavassa, Xavier Haubois, Claudia Paladini, Narsireddy Anugu, Peter Scicluna, Andrea K. Dupree, L. Decin, Philippe Stee, Bruno Lopez, Gioia Rau, M. Montargès, William C. Danchi, K. Kravchenko, S. T. Ridgway, Ryan P. Norris, J. Sanchez-Bermudez, Pierre Kervella, Faustine Cantalloube, J-B. Le Bouquin, Markus Wittkowski, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Laboratoire Lagrange, Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS., Anton Pannenkoek Institute for Astronomy [University of Amsterdam], University of Amsterdam [Amsterdam] (UvA), Max Planck Institute for Astronomy (MPIA), Instituto de Astronomía, Univ. Nacional Autónoma de México, Universidad Nacional Autónoma de México (UNAM), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), School of Chemistry [Leeds], University of Leeds, Max Planck Institute for Extraterrestrial Physics (MPE), Max-Planck-Gesellschaft, Harvard-Smithsonian Center for Astrophysics (CfA), Smithsonian Institution-Harvard University [Cambridge], NSF’s National Optical-Infrared Astronomy Research Laboratory (NOIRLab), Steward Observatory, University of Arizona, School of Physics and Astronomy [Exeter], University of Exeter, Physics Department [New Mexico Institute of Mining and Technology], New Mexico Institute of Mining and Technology [New Mexico Tech] (NMT), GSFC Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center (GSFC), Department of Physics [Catholic University of America], Catholic University of America, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Astronomy University of Michigan, University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Low Energy Astrophysics (API, FNWI)
Subjects: Brightness, SURFACE, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, STELLAR CONVECTION, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Apparent magnitude, INTERSTELLAR SILICATE MINERALOGY, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, IIP SUPERNOVA, Red supergiant, 010306 general physics, 010303 astronomy & astrophysics, Stellar evolution, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, ComputingMilieux_MISCELLANEOUS, Betelgeuse, Physics, Photosphere, Multidisciplinary, Science & Technology, Multidisciplinary Sciences, Supernova, Neutron star, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, [SDU]Sciences of the Universe [physics], NEAR-IR, Science & Technology - Other Topics, RED SUPERGIANTS, STEPS, Astrophysics::Earth and Planetary Astrophysics
Abstract: Red supergiants are the most common final evolutionary stage of stars that have initial masses between 8 and 35 times that of the Sun1. During this stage, which lasts roughly 100,000 years1, red supergiants experience substantial mass loss. However, the mechanism for this mass loss is unknown2. Mass loss may affect the evolutionary path, collapse and future supernova light curve3 of a red supergiant, and its ultimate fate as either a neutron star or a black hole4. From November 2019 to March 2020, Betelgeuse—the second-closest red supergiant to Earth (roughly 220 parsecs, or 724 light years, away)5,6—experienced a historic dimming of its visible brightness. Usually having an apparent magnitude between 0.1 and 1.0, its visual brightness decreased to 1.614 ± 0.008 magnitudes around 7–13 February 20207—an event referred to as Betelgeuse’s Great Dimming. Here we report high-angular-resolution observations showing that the southern hemisphere of Betelgeuse was ten times darker than usual in the visible spectrum during its Great Dimming. Observations and modelling support a scenario in which a dust clump formed recently in the vicinity of the star, owing to a local temperature decrease in a cool patch that appeared on the photosphere. The directly imaged brightness variations of Betelgeuse evolved on a timescale of weeks. Our findings suggest that a component of mass loss from red supergiants8 is inhomogeneous, linked to a very contrasted and rapidly changing photosphere. The southern hemisphere of Betelgeuse during its Great Dimming was an order of magnitude darker than usual, owing to a cool patch on the photosphere and associated dust formation.
Published: 2021

36. VizieR Online Data Catalog: VLT/SPHERE Y-band images of MWC 758 at two epochs (Ren+, 2020)

Author: Ren, B., Dong, R., Holstein, R. G., Ruffio, J. -B., Calvin, B. A., Girard, J. H., Benisty, M., Boccaletti, A., Esposito, T. M., Choquet, Elodie, Mawet, D., Pueyo, L., Stolker, T., Chiang, E., Boer, J., Debes, J. H., Garufi, A., Grady, C. A., Hines, D. C., Maire, A. -L., Menard, F., Millar-Blanchaer, M. A., Perrin, M. D., Poteet, C. A., Schneider, G., Caltech Department of Astronomy [Pasadena], California Institute of Technology (CALTECH), University of Victoria [Canada] (UVIC), Leiden Observatory [Leiden], Universiteit Leiden, European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Space Telescope Science Institute (STSci), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Unidad Mixta Internacional Franco-Chilena de Astromia, Universidad de Chile (CNRS/INSU), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Department of Astronomy [Berkeley], University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), INAF - Osservatorio Astrofisico di Arcetri (OAA), Istituto Nazionale di Astrofisica (INAF), GSFC Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center (GSFC), Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, Steward Observatory, and University of Arizona
Subjects: [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Infrared sources, YSOs
Abstract: More than a dozen young stars host spiral arms in their surrounding protoplanetary disks. The excitationmechanisms of such arms are under debate. The two leading hypotheses – companion-disk interaction andgravitational instability (GI) – predict distinct motion for spirals. By imaging the MWC 758 spiral arm systemat two epochs spanning ∼5 yr using the SPHERE instrument on the Very Large Telescope (VLT), we test thetwo hypotheses for the first time. We find that the pattern speeds of the spirals are not consistent with the GIorigin. Our measurements further evince the existence of a faint “missing planet” driving the disk arms. Theaverage spiral pattern speed is 0.◦22 ± 0.◦03 yr−1, pointing to a driver at 172+18−14 au around a 1.9 M centralstar if it is on a circular orbit. In addition, we witness time varying shadowing effects on a global scale that arelikely originated from an inner disk
Published: 2022

37. III. On-sky validation in VLT/SPHERE

Author: Vigan, Arthur, N’Diaye, Mamadou, Dohlen, Kjetil, Sauvage, Jean-François, Milli, Julien, Zins, Gérard, Petit, Cyril, Wahhaj, Zahed, Cantalloube, Faustine, Caillat, Amandine, Costille, Anne, Le merrer, Joël, Carlotti, Alexis, Beuzit, Jean-Luc, Mouillet, David, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Aix Marseille Université (AMU), Université Côte d'Azur (UCA), Centre National de la Recherche Scientifique (CNRS), Space Telescope Science Institute (STSci), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), DOTA, ONERA, Université Paris Saclay (COmUE) [Châtillon], ONERA-Université Paris Saclay (COmUE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [SDU]Sciences of the Universe [physics], instrumentation: high angular resolution, techniques: high angular resolution, telescopes, instrumentation: adaptive optics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], ComputingMilieux_MISCELLANEOUS
Abstract: International audience; Coronagraphic imaging of exoplanets and circumstellar environments using ground-based instruments on large telescopes is intrinsically limited by speckles induced by uncorrected aberrations. These aberrations originate from the imperfect correction of the atmosphere by an extreme adaptive optics system; from static optical defects; or from small opto-mechanical variations due to changes in temperature, pressure, or gravity vector. More than the speckles themselves, the performance of high-contrast imagers is ultimately limited by their temporal stability, since most post-processing techniques rely on difference of images acquired at different points in time. Identifying the origin of the aberrations and the timescales involved is therefore crucial to understanding the fundamental limits of dedicated high-contrast instruments. In previous works we demonstrated the use of a Zernike wavefront sensor called ZELDA for sensing non-common path aberrations (NCPA) in the VLT/SPHERE instrument. We now use ZELDA to investigate the stability of the instrumental aberrations using five long sequences of measurements obtained at high cadence on the internal calibration source. Our study reveals two regimes of decorrelation of the NCPA. The first, with a characteristic timescale of a few seconds and an amplitude of a few nanometers, is induced by a fast internal turbulence within the enclosure. The second is a slow quasi-linear decorrelation on the order of a few 10−3 nmrms s−1 that acts on timescales from minutes to hours. We use coronagraphic image reconstruction to demonstrate that these two NCPA contributions have a measurable impact on differences of images, and that the fast internal turbulence is a dominating term over to the slow linear decorrelation. We also use dedicated sequences where the derotator and atmospheric dispersion compensators emulate a real observation to demonstrate the importance of performing observations symmetric around the meridian, which minimizes speckle decorrelation, and therefore maximizes the sensitivity to point sources in difference of images.
Published: 2022

38. MATISSE, the VLTI mid-infrared imaging spectro-interferometer

Author: Lopez, B., Lagarde, S., Petrov, R.G., Jaffe, W., Antonelli, P., Allouche, F., Berio, P., Matter, A., Meilland, A., Millour, F., Robbe-Dubois, S., Henning, T., Weigelt, G., Glindemann, A., Agocs, T., Bailet, C., Beckmann, U., Bettonvil, F., Boekel, R. van, Bourget, P., Bresson, Y., Bristow, P., Cruzalèbes, P., Eldswijk, E., Fanteï Caujolle, Y., González Herrera, J.C., Graser, U., Guajardo, P., Heininger, M., Hofmann, K.H., Kroes, G., Laun, W., Lehmitz, M., Leinert, C., Meisenheimer, K., Morel, S., Neumann, U., Paladini, C., Percheron, I., Riquelme, M., Schoeller, M., Stee, P., Venema, L., Woillez, J., Zins, G., Ábrahám, P., Abadie, S., Abuter, R., Accardo, M., Adler, T., Alonso, J., Augereau, J.-C., Böhm, A., Bazin, G., Beltran, J., Bensberg, A., Boland, W., Brast, R., Burtscher, L., Castillo, R., Chelli, A., Cid, C., Clausse, J.-M., Connot, C., Conzelmann, R.D., Danchi, W.C., Delbo, M., Drevon, J., Dominik, C., Duin, A. van, Ebert, M., Eisenhauer, F., Flament, S., Frahm, R., Gámez Rosas, V., Gabasch, A., Gallenne, A., Garces, E., Girard, P., Glazenborg, A., Gonté, F.Y.J., Guitton, F., Haan, M. de, Hanenburg, H., Haubois, X., Hocdé, V., Hogerheijde, M., Horst, R. ter, Hron, J., Hummel, C.A., Hubin, N., Huerta, R., Idserda, J., Isbell, J.W., Ives, D., Jakob, G., Jaskó, A., Jochum, L., Klarmann, L., Klein, R., Kragt, J., Kuindersma, S., Kokoulina, E., Labadie, L., Lacour, S., Leftley, J., Le Poole, R., Lizon, J.L., Lopez, M., Lykou, F., Mérand, A., Marcotto, A., Mauclert, N., Maurer, T., Mehrgan, L.H., Meisner, J., Meixner, K., Mellein, M., Menut, J.L., Mohr, L., Mosoni, L., Navarro, R., Nußbaum, E., Pallanca, L., Pantin, E., Pasquini, L., Phan Duc, T., Pott, J.U., Pozna, E., Richichi, A., Ridinger, A., Rigal, F., Rivinius, T., Roelfsema, R., Rohloff, R.-R., Rousseau, S., Salabert, D., Schertl, D., Schuhler, N., Schuil, M., Shabun, K., Soulain, A., Stephan, C., Toledo, P., Tristram, K., Tromp, N., Vakili, F., Varga, J., Vinther, J., Waters, L.B.F.M., Wittkowski, M., Wolf, S., Wrhel, F., Yoffe, G., Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Max-Planck-Institut für Radioastronomie (MPIFR), European Southern Observatory (ESO), Low Energy Astrophysics (API, FNWI), Université Côte d'Azur (UCA), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden, Centre de Développement des Energies Renouvelables (CDER), Ministère de l'Enseignement Supérieur et de la Recherche Scientifique [Algérie] (MESRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Astronomy (MPIA), European Southern Observatory Headquarters, NOVA Optical IR Instrumentation Group, Centre Hospitalier Universitaire d'Angers (CHU Angers), PRES Université Nantes Angers Le Mans (UNAM), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Kiel University, NASA Goddard Space Flight Center (GSFC), Universiteit van Amsterdam (UvA), Max Planck Institute for Extraterrestrial Physics (MPE), Miniaturisation pour la Synthèse, l’Analyse et la Protéomique - UAR 3290 (MSAP), Université de Lille-Centre National de la Recherche Scientifique (CNRS), Universidad de Concepción - University of Concepcion [Chile], médialab (Sciences Po) (médialab), Sciences Po (Sciences Po), Polish Academy of Sciences (PAN), Universität zu Köln = University of Cologne, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), École, mutations, apprentissages (EMA), CY Cergy Paris Université (CY), Konkoly Observatory, Research Centre for Astronomy and Earth Sciences [Budapest], Hungarian Academy of Sciences (MTA)-Hungarian Academy of Sciences (MTA), Géoazur (GEOAZUR 7329), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Zselic Park of Stars, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Department of Hematology, Instituto Superiore di Sanita Roma, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Institut National du Cancer [Boulogne Billancourt] (INC), and Radboud University [Nijmegen]
Subjects: [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astronomy, Astrophysics::Instrumentation and Methods for Astrophysics, FOS: Physical sciences, Astronomy and Astrophysics, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Space and Planetary Science, instrumentation: high angular resolution, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, methods: observational, instrumentation: interferometers, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract: Context:Optical interferometry is at a key development stage. ESO's VLTI has established a stable, robust infrastructure for long-baseline interferometry for general astronomical observers. The present second-generation instruments offer a wide wavelength coverage and improved performance. Their sensitivity and measurement accuracy lead to data and images of high reliability. Aims:We have developed MATISSE, the Multi AperTure mid-Infrared SpectroScopic Experiment, to access high resolution imaging in a wide spectral domain and explore topics such: stellar activity and mass loss; planet formation and evolution in the gas and dust disks around young stars; accretion processes around super massive black holes in AGN. Methods:The instrument is a spectro-interferometric imager covering three atmospheric bands (L,M,N) from 2.8 to 13.0 mu, combining four optical beams from the VLTI's telscopes. Its concept, related observing procedure, data reduction and calibration approach are the product of 30 years of instrumental research. The instrument utilizes a multi-axial beam combination that delivers spectrally dispersed fringes. The signal provides the following quantities at several spectral resolutions: photometric flux, coherent fluxes, visibilities, closure phases, wavelength differential visibilities and phases, and aperture-synthesis imaging. Results:We provide an overview of the physical principle of the instrument and its functionalities, the characteristics of the delivered signal, a description of the observing modes and of their performance limits. An ensemble of data and reconstructed images are illustrating the first acquired key observations. Conclusion:The instrument has been in operation at Cerro Paranal, ESO, Chile since 2018, and has been open for science use by the international community since April 2019. The first scientific results are being published now., 24 pages, 26 figures, submitted to Astronomy & Astrophysics
Published: 2022

39. The First Near-infrared Transmission Spectrum of HIP 41378 f, A Low-mass Temperate Jovian World in a Multiplanet System

Author: Alam, MK, Kirk, J, Dressing, CD, López-Morales, M, Ohno, K, Gao, P, Akinsanmi, B, Santerne, A, Grouffal, S, Adibekyan, V, Barros, SCC, Buchhave, LA, Crossfield, IJM, Dai, F, Deleuil, M, Giacalone, S, Lillo-Box, J, Marley, M, Mayo, AW, Mortier, A, Santos, NC, Sousa, SG, Turtelboom, EV, Wheatley, PJ, Vanderburg, AM, Alam, MK [0000-0003-4157-832X], Kirk, J [0000-0002-4207-6615], Dressing, CD [0000-0001-8189-0233], López-Morales, M [0000-0003-3204-8183], Ohno, K [0000-0003-3290-6758], Gao, P [0000-0002-8518-9601], Akinsanmi, B [0000-0001-6519-1598], Santerne, A [0000-0002-3586-1316], Grouffal, S [0000-0002-2805-5869], Adibekyan, V [0000-0002-0601-6199], Barros, SCC [0000-0003-2434-3625], Buchhave, LA [0000-0003-1605-5666], Crossfield, IJM [0000-0002-1835-1891], Dai, F [0000-0002-8958-0683], Deleuil, M [0000-0001-6036-0225], Giacalone, S [0000-0002-8965-3969], Lillo-Box, J [0000-0003-3742-1987], Marley, M [0000-0002-5251-2943], Mayo, AW [0000-0002-7216-2135], Mortier, A [0000-0001-7254-4363], Santos, NC [0000-0003-4422-2919], Sousa, SG [0000-0001-9047-2965], Turtelboom, EV [0000-0002-1845-2617], Wheatley, PJ [0000-0003-1452-2240], Vanderburg, AM [0000-0001-7246-5438], Apollo - University of Cambridge Repository, Alam, Munazza K. [0000-0003-4157-832X], Kirk, James [0000-0002-4207-6615], Dressing, Courtney D. [0000-0001-8189-0233], López-Morales, Mercedes [0000-0003-3204-8183], Ohno, Kazumasa [0000-0003-3290-6758], Gao, Peter [0000-0002-8518-9601], Akinsanmi, Babatunde [0000-0001-6519-1598], Santerne, Alexandre [0000-0002-3586-1316], Grouffal, Salomé [0000-0002-2805-5869], Adibekyan, Vardan [0000-0002-0601-6199], Barros, Susana C. C. [0000-0003-2434-3625], Buchhave, Lars A. [0000-0003-1605-5666], Crossfield, Ian J. M. [0000-0002-1835-1891], Dai, Fei [0000-0002-8958-0683], Deleuil, Magali [0000-0001-6036-0225], Giacalone, Steven [0000-0002-8965-3969], Lillo-Box, Jorge [0000-0003-3742-1987], Marley, Mark [0000-0002-5251-2943], Mayo, Andrew W. [0000-0002-7216-2135], Mortier, Annelies [0000-0001-7254-4363], Santos, Nuno C. [0000-0003-4422-2919], Sousa, Sérgio G. [0000-0001-9047-2965], Turtelboom, Emma V. [0000-0002-1845-2617], Wheatley, Peter J. [0000-0003-1452-2240], Vanderburg, Andrew M. [0000-0001-7246-5438], Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Carnegie Institution for Science, Centre for Star and Planet Formation (STARPLAN), Globe Institute, Faculty of Health and Medical Sciences, University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH)-Faculty of Health and Medical Sciences, University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), University of Arizona, Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), and University of Warwick [Coventry]
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], The Solar System, Exoplanets, and Astrobiology, Exoplanets, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, [SDU]Sciences of the Universe [physics], Space and Planetary Science, astro-ph.EP, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, QB, Astrophysics - Earth and Planetary Astrophysics, Exoplanet atmospheres
Abstract: We present a near-infrared transmission spectrum of the long period (P=542 days), temperate ($T_{eq}$=294 K) giant planet HIP 41378 f obtained with the Wide-Field Camera 3 (WFC3) instrument aboard the Hubble Space Telescope (HST). With a measured mass of 12 $\pm$ 3 $M_{\oplus}$ and a radius of 9.2 $\pm$ 0.1 $R_{\oplus}$, HIP 41378 f has an extremely low bulk density (0.09 $\pm$ 0.02 g/cm$^{3}$). We measure the transit depth with a median precision of 84 ppm in 30 spectrophotometric channels with uniformly-sized widths of 0.018 microns. Within this level of precision, the spectrum shows no evidence of absorption from gaseous molecular features between 1.1-1.7 microns. Comparing the observed transmission spectrum to a suite of 1D radiative-convective-thermochemical-equilibrium forward models, we rule out clear, low-metallicity atmospheres and find that the data prefer high-metallicity atmospheres or models with an additional opacity source such as high-altitude hazes and/or circumplanetary rings. We explore the ringed scenario for this planet further by jointly fitting the K2 and HST light curves to constrain the properties of putative rings. We also assess the possibility of distinguishing between hazy, ringed, and high-metallicity scenarios at longer wavelengths with JWST. HIP 41378 f provides a rare opportunity to probe the atmospheric composition of a cool giant planet spanning the gap between the Solar System giants, directly imaged planets, and the highly-irradiated hot Jupiters traditionally studied via transit spectroscopy., 12 pages, 4 figures, accepted to ApJL. Please also see companion paper Ohno & Fortney (2022) for further details on the ring modeling methodology (arxiv DOI: 2201.02794)
Published: 2022

40. M-type (22) Kalliope: A tiny Mercury

Author: Ferrais, Marin, Jorda, L., Vernazza, Pierre, Carry, Benoit, Broz, M., Rambaux, N., Hanus, J., Dudzinski, G., Bartczak, P., Vachier, F., Aristidi, Eric, Beck, P., Marchis, F., Marsset, M., Viikinkoski, M., Fetick, R., Drouard, A., Fusco, T., Birlan, M., Podlewska-Gaca, E., Burbine, T.H., Dyar, M.D., Bendjoya, Philippe, Benkhaldoun, Zouhair, Berthier, Jérôme, Castillo-Rogez, Julie, Cipriani, Fabrice, Colas, F., Dumas, Christophe, Ďurech, J., Fauvaud, S., Grice, J., Jehin, Emmanuël, Kaasalainen, M., Kryszczynska, A., Lamy, Philippe, Coroller, H., Marciniak, Alexandre, Michalowski, T., Michel, Patrick, Prieur, Jean-Louis, Reddy, V., Rivet, Jean‐pierre, Santana-Ros, Toni, Scardia, Marco, Tanga, Paolo, Vigan, Arthur, Witasse, Olivier, Yang, B., Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Astronomical Institute of Charles University, Charles University [Prague] (CU), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Astronomical Observatory [Poznan], Adam Mickiewicz University in Poznań (UAM), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, SETI Institute, Department of Earth, Atmospheric and Planetary Sciences [MIT, Cambridge] (EAPS), Massachusetts Institute of Technology (MIT), University of Tampere [Finland], ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, Astronomical Institute of Romanian Academy, Romanian Academy, Institute of Physics [Szczecin], University of Szczecin, Department of Astronomy of the Mount Holyoke College, Mount Holyoke College, Oukaimeden Observatory, Université Cadi Ayyad [Marrakech] (UCA), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA), TMT International Observatory, Observatoire du Bois de Bardon, School of Physical Sciences [Milton Keynes], Faculty of Science, Technology, Engineering and Mathematics [Milton Keynes], The Open University [Milton Keynes] (OU)-The Open University [Milton Keynes] (OU), Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, HELIOS - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Lunar and Planetary Laboratory [Tucson] (LPL), University of Arizona, Departamento de Fisica, Ingenieria de Sistemas y Teoria de la Señal [Alicante] (DFESTS), Universidad de Alicante, Institut de Ciencies del Cosmos (ICCUB), Universitat de Barcelona (UB), INAF - Osservatorio Astronomico di Brera (OAB), Istituto Nazionale di Astrofisica (INAF), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Universidad Diego Portales [Santiago] (UDP), DOTA, ONERA [Salon], ONERA, DOTA, ONERA, Université Paris Saclay [Palaiseau], Agence Spatiale Européenne = European Space Agency (ESA), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 199.C-0074 (PI: P. Vernazza). P. V., A. D., M. F. and B. C. were supported by CNRS/INSU/PNP. The research of J.H. has been supported by the Czech Science Foundation through grant 20-08218S and by Charles University Research program no. UNCE/SCI/023. M.B. was supported by the Czech Science Foundation, grant 21-11058S. F.M. is supported by the National Science Foundation under grant no. 1743015. TRAPPIST is a project funded by the Belgian Fonds (National) de la Recherche Scientifique (F.R.S.-FNRS) under grant PDR T.0120.21. TRAPPIST-North is a project funded by the University of Liège, in collaboration with the Cadi Ayyad University of Marrakech (Morocco). E.J. is F.R.S.-FNRS Senior Research Associate. The work of T.S.R. was carried out through grant APOSTD/2019/046 by Generalitat Valenciana (Spain). This work was supported by the MINECO (Spanish Ministry of Economy) through grant RTI2018-095076-B-C21 (MINECO/FEDER, UE)., Universidad de Alicante. Instituto Universitario de Física Aplicada a las Ciencias y las Tecnologías, Tampere University, Computing Sciences, Centre National de la Recherche Scientifique (France), Charles University (Czech Republic), Czech Science Foundation, Fonds de La Recherche Scientifique (Belgique), National Science Foundation (US), Université Cadi Ayyad, Generalitat Valenciana, Ministerio de Economía y Competitividad (España), Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), and European Commission
Subjects: asteroids, Astronomy and Astrophysics, Observation, (22) Kalliope, Techniques: high angular resolution, high angular resolution [Techniques], individual: (22) Kalliope [Minor planets, asteroids], Methods: observational, Space and Planetary Science, Asteroids: individual: (22) Kalliope, 111 Mathematics, minor planets, observational [Methods], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], high angular resolution, ComputingMilieux_MISCELLANEOUS, Astronomía y Astrofísica
Abstract: M.Ferrais et al., [Context] Asteroid (22) Kalliope is the second largest M-type asteroid in the main belt and is orbited by a satellite, Linus. Whereas the mass of Kalliope is already well constrained thanks to the presence of a moon, its volume is still poorly known, leading to uncertainties on its bulk density and internal structure., [Aims] We aim to refine the shape of (22) Kalliope and thus its diameter and bulk density, as well as the orbit of its moon to better constrain its mass, hence density and internal structure., [Methods] We acquired disk-resolved observations of (22) Kalliope using the VLT/SPHERE/ZIMPOL instrument to reconstruct its three-dimensional (3D) shape using three different modeling techniques. These images were also used together with new speckle observations at the C2PU/PISCO instrument as well as archival images from other large ground-based telescopes to refine the orbit of Linus., [Results] The volume of (22) Kalliope given by the shape models, corresponding to D = 150 ± 5 km, and the mass constrained by its satellite’s orbit yield a density of ρ = 4.40 ± 0.46 g cm−3. This high density potentially makes (22) Kalliope the densest known small body in the Solar System. A macroporosity in the 10–25% range (as expected for this mass and size), implies a grain density in the 4.8–5.9 g cm−3 range. Kalliope’s high bulk density, along with its silicate-rich surface implied by its low radar albedo, implies a differentiated interior with metal contributing to most of the mass of the body., [Conclusions] Kalliope’s high metal content (40–60%) along with its metal-poor mantle makes it the smallest known Mercury-like body. A large impact at the origin of the formation of the moon Linus is likely the cause of its high metal content and density., Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programme 199.C-0074 (PI: P. Vernazza). P. V., A. D., M. F. and B. C. were supported by CNRS/INSU/PNP. The research of J.H. has been supported by the Czech Science Foundation through grant 20-08218S and by Charles University Research program no. UNCE/SCI/023. M.B. was supported by the Czech Science Foundation, grant 21-11058S. F.M. is supported by the National Science Foundation under grant no. 1743015. TRAPPIST is a project funded by the Belgian Fonds (National) de la Recherche Scientifique (F.R.S.-FNRS) under grant PDR T.0120.21. TRAPPIST-North is a project funded by the University of Liège, in collaboration with the Cadi Ayyad University of Marrakech (Morocco). E.J. is F.R.S.-FNRS Senior Research Associate. The work of T.S.R. was carried out through grant APOSTD/2019/046 by Generalitat Valenciana (Spain). This work was supported by the MINECO (Spanish Ministry of Economy) through grant RTI2018-095076-B-C21 (MINECO/FEDER, UE).
Published: 2022

41. Performance characterization and near-realtime monitoring of MUSE adaptive optics modes at Paranal

Author: Thomas Wevers, Fernando J. Selman, Axel Reyes, Macarena Vega Pallauta, Johanna Hartke, Fuyan Bian, Olivier A. Beltramo-Martin, Romain Fetick, Sebastian Kamann, Johann Kolb, Timo Kravtsov, Cristobal Moya, Benoit Neichel, Sylvain Oberti, Claudia Reyes, Elena Valenti, European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Laboratoire d'Astrophysique de Marseille (LAM), and Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: stars, integral field spectrographs, point spread functions, FOS: Physical sciences, Astrophysics - Instrumentation and Methods for Astrophysics, calibration, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Adaptive optics, Instrumentation and Methods for Astrophysics (astro-ph.IM), QC, QB, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM]
Abstract: The Multi Unit Spectroscopic Explorer (MUSE) is an integral field spectrograph on the Very Large Telescope Unit Telescope 4, capable of laser guide star assisted and tomographic adaptive optics using the GALACSI module. Its observing capabilities include a wide field (1 square arcmin), ground layer AO mode (WFM-AO) and a narrow field (7.5"x7.5"), laser tomography AO mode (NFM-AO). The latter has had several upgrades in the 4 years since commissioning, including an optimisation of the control matrices for the AO system and a new sub-electron noise detector for its infra-red low order wavefront sensor. We set out to quantify the NFM-AO system performance by analysing $\sim$230 spectrophotometric standard star observations taken over the last 3 years. To this end we expand upon previous work, designed to facilitate analysis of the WFM-AO system performance. We briefly describe the framework that will provide a user friendly, semi-automated way for system performance monitoring during science operations. We provide the results of our performance analysis, chiefly through the measured Strehl ratio and full width at half maximum (FWHM) of the core of the point spread function (PSF) using two PSF models, and correlations with atmospheric conditions. These results will feed into a range of applications, including providing a more accurate prediction of the system performance as implemented in the exposure time calculator, and the associated optimization of the scientific output for a given set of limiting atmospheric conditions., Comment: SPIE proceedings (2022), Observatory Operations: Strategies, Processes, and Systems IX
Published: 2022
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42. The 10th VLTI School of Interferometry: Premiering a Fully Online Format

Author: Millour, Florentin, Meilland, Anthony, Matter, Alexis, Mella, Guillaume, Bourgès, Laurent, Paladini, Claudia, Tallon-Bosc, Isabelle, Tallon, Michel, Soulez, Ferreol, Buscher, David, Mérand, Antoine, Benisty, Myriam, van Boekel, Roy, Cruzalèbes, Pierre, Defrère, Denis, Domiciano de Souza, Armando, Filho, Mercedes, Garcia, Paulo, Hönig, Sebastian, Ligi, Roxanne, Maccotta, Camille, Mckean, John, Patru, Fabien, Perraut, Karine, Pott, Jörg-Uwe, Spang, Alain, Rousset, Sophie, Astronomy, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Cavendish Laboratory, University of Cambridge [UK] (CAM), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Max Planck Institute for Astronomy (MPIA), Institute of Astronomy [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), CENTRA and Universidade do Porto - Faculdade de Engenharia, 4200-465, Porto, Portugal, School of Physics and Astronomy [Southampton], University of Southampton, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Netherlands Institute for Radio Astronomy (ASTRON), Chaire IPAG 'Entreprise Inclusive' (IPAG Business School), and IPAG Business School
Subjects: [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Very Large Telescope Inerferometer (VLTI) schools have nearly a 20-year history and have trained a significant fraction of today��s optical interferometrists who use high-angular-resolution techniques on a regular basis. Very early in the development of the VLTI, training was identified by the community as a necessary tool, as the expertise in optical long-baseline interferometry was limited to a few groups in France and Germany (in those early years the UK was not an ESO member state). The first VLTI school took place in Les Houches, France, in 2002 and since then VLTI schools have been organised in several locations (France, Germany, Hungary, Poland, Portugal) roughly every two years, the previous one being held in 2018 in Lisbon. The VLTI schools are funded and coordinated through the European Interferometry Initiative (Eii)., Published in The Messenger vol. 185, pp. 28-30, December 2021.
Published: 2021

43. TOI-431/HIP 26013: a super-Earth and a sub-Neptune transiting a bright, early K dwarf, with a third RV planet

Author: Andrés Jordán, Sara Seager, Brett C. Addison, Maximilian N. Günther, Monika Lendl, Jack Okumura, Jorge Lillo-Box, Jon M. Jenkins, Roland Vanderspek, C. G. Tinney, Benjamin J. Fulton, Peter J. Wheatley, Erik A. Petigura, Beth A. Henderson, C. Stibbard, P. Figueira, Rafael Brahm, Eric L. N. Jensen, Michael Reefe, Cesar Briceno, Chris Stockdale, S. Hojjatpanah, Farisa Y. Morales, Alexis M. S. Smith, Caroline Dorn, Thomas Henning, Vardan Adibekyan, George W. King, Lauren M. Weiss, David R. Ciardi, Howard Isaacson, Richard P. Schwarz, Thomas Barclay, Stephen R. Kane, Keivan G. Stassun, David W. Latham, Malcolm Fridlund, Jack S. Acton, Ravit Helled, Sharon X. Wang, John Berberian, Joseph D. Twicken, J. F. Otegi, David R. Anderson, Sarah L. Casewell, Elise Furlan, Elisabeth Matthews, Johanna Teske, Rodrigo F. Díaz, Samuel Gill, Daniel Bayliss, Ian Crossfield, Peter Plavchan, Matthew W. Mengel, Joshua E. Schlieder, John F. Kielkopf, Stéphane Udry, E. Delgado Mena, H. P. Osborn, Avi Shporer, R. Cloutier, J. Villasenor, Duncan J. Wright, E. Gaidos, A. Osborn, K. I. Collins, Angelle Tanner, Nicholas M. Law, Björn Benneke, Joshua N. Winn, Fei Dai, Nicholas J. Scott, Erica J. Gonzales, Courtney D. Dressing, Sarah Ballard, Don Pollacco, Coel Hellier, Michael R. Goad, David J. Armstrong, Varoujan Gorjian, Paula Sarkis, Richard C. Kidwell, F. Zohrabi, Nuno C. Santos, David Barrado, Matthew R. Burleigh, Sergio Hoyer, Claire Geneser, Christopher J. Burke, Richard G. West, James McCormac, P. A. Strøm, Daniel Huber, Aleisha Hogan, Paul Robertson, Natalie M. Batalha, Edward M. Bryant, Liam Raynard, Karen A. Collins, Robert A. Wittenmyer, Mark E. Rose, Rachel A. Matson, Steve B. Howell, James S. Jenkins, Jose I. Vines, S. C. C. Barros, Néstor Espinoza, B. Cale, Andrew W. Howard, Diana Dragomir, Alexandre Santerne, M. Lund, Olivier Demangeon, Brendan P. Bowler, Benjamin F. Cooke, Xavier Dumusque, Andrew W. Mann, Hui Zhang, Carl Ziegler, Arpita Roy, Rosanna H. Tilbrook, Sérgio F. Sousa, George R. Ricker, Jonathan Horner, Elisa V. Quintana, Thiam-Guan Tan, Louise D. Nielsen, François Bouchy, University of New South Wales [Sydney] (UNSW), McDonald Observatory, University of Texas at Austin [Austin], Leiden Observatory [Leiden], Universiteit Leiden, Chalmers University of Technology [Gothenburg, Sweden], NASA Ames Research Center Cooperative for Research in Earth Science in Technology (ARC-CREST), NASA Ames Research Center (ARC), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Instituto de Astrofísica e Ciências do Espaço (IASTRO), Center for Space Research [Cambridge] (CSR), Massachusetts Institute of Technology (MIT), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, European Space Astronomy Centre (ESAC), Agence Spatiale Européenne = European Space Agency (ESA), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Département de Physique [Montréal], Université de Montréal (UdeM), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Physics and Astronomy [Leicester], University of Leicester, Infrared Processing and Analysis Center (IPAC), California Institute of Technology (CALTECH), Optimisation - Système - Energie (GEPEA-OSE), Laboratoire de génie des procédés - environnement - agroalimentaire (GEPEA), Institut Universitaire de Technologie - Nantes (IUT Nantes), Université de Nantes (UN)-Université de Nantes (UN)-Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Institut Universitaire de Technologie Saint-Nazaire (IUT Saint-Nazaire), Université de Nantes (UN)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-École nationale vétérinaire, agroalimentaire et de l'alimentation Nantes-Atlantique (ONIRIS)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut Universitaire de Technologie - La Roche-sur-Yon (IUT La Roche-sur-Yon), Université de Nantes (UN)-Institut Universitaire de Technologie - Nantes (IUT Nantes), Université de Nantes (UN), Institut für Virologie, Philipps University, MIT Kavli Institute for Astrophysics and Space Research, Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Department of Geology and Geophysics [Mānoa], University of Hawai‘i [Mānoa] (UHM), Universität Zürich [Zürich] = University of Zurich (UZH), Department of Earth and Planetary Science [UC Berkeley] (EPS), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), Universidad de Chile = University of Chile [Santiago] (UCHILE), Pontificia Universidad Católica de Chile (UC), University of Louisville, Austrian Academy of Sciences (OeAW), Lund University [Lund], University of Warwick [Coventry], Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Physikalisches Institut [Bern], Universität Bern [Bern] (UNIBE), German Aerospace Center (DLR), Swiss Bee Research Centre, Centre for Medical Image Computing (CMIC), and University College of London [London] (UCL)
Subjects: (TOI-431, planets and satellites: detection, Fundamental Parameters, 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], (TOI-431, TIC 31374837), FOS: Physical sciences, Individual, Astrophysics, Q1, 01 natural sciences, Neptune, Planet, QB460, 0103 physical sciences, planets and satellites: fundamental parameters, 010303 astronomy & astrophysics, QB600, QC, 0105 earth and related environmental sciences, QB, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Super-Earth, Astronomy and Astrophysics, Planets and Satellites, Radius, Light curve, Exoplanet, Radial velocity, Photometry (astronomy), Detection, 13. Climate action, Space and Planetary Science, planets and satellites: individual: (TOI-431, TIC 31374837), Astrophysics - Earth and Planetary Astrophysics
Abstract: We present the bright (V$_{mag} = 9.12$), multi-planet system TOI-431, characterised with photometry and radial velocities. We estimate the stellar rotation period to be $30.5 \pm 0.7$ days using archival photometry and radial velocities. TOI-431b is a super-Earth with a period of 0.49 days, a radius of 1.28 $\pm$ 0.04 R$_{\oplus}$, a mass of $3.07 \pm 0.35$ M$_{\oplus}$, and a density of $8.0 \pm 1.0$ g cm$^{-3}$; TOI-431d is a sub-Neptune with a period of 12.46 days, a radius of $3.29 \pm 0.09$ R$_{\oplus}$, a mass of $9.90^{+1.53}_{-1.49}$ M$_{\oplus}$, and a density of $1.36 \pm 0.25$ g cm$^{-3}$. We find a third planet, TOI-431c, in the HARPS radial velocity data, but it is not seen to transit in the TESS light curves. It has an $M \sin i$ of $2.83^{+0.41}_{-0.34}$ M$_{\oplus}$, and a period of 4.85 days. TOI-431d likely has an extended atmosphere and is one of the most well-suited TESS discoveries for atmospheric characterisation, while the super-Earth TOI-431b may be a stripped core. These planets straddle the radius gap, presenting an interesting case-study for atmospheric evolution, and TOI-431b is a prime TESS discovery for the study of rocky planet phase curves., Comment: 21 pages, 11 figures, 3 appendices, accepted for publication in MNRAS
Published: 2021

44. VLT/SPHERE imaging survey of the largest main-belt asteroids: Final results and synthesis

Author: J. Krajewski, P. Aurard, Philippe Lamy, Vishnu Reddy, Laurent Jorda, D. Molina, Josef Hanus, Josef Ďurech, P. Michel, F. Vachier, Nicolas Rambaux, J. Oey, Grzegorz Dudziński, P. Bartczak, A. Leroy, Michael Marsset, L. Dalmon, P. Beck, H. Le Coroller, Hiroko Hamanowa, Maëlle Neveu, Christophe Dumas, Hiromi Hamanowa, A. G. Sanchez, Zouhair Benkhaldoun, N. Payre, E. Podlewska-Gaca, Fabrice Cipriani, Raoul Behrend, Paolo Tanga, Aled Jones, Julie Castillo-Rogez, Miroslav Brož, P. Antonini, Tadeusz Michalowski, F. Livet, O. Labrevoir, J. M. Bosch, Emmanuel Jehin, Arthur Vigan, S. Fauvaud, A. Chapman, Marin Ferrais, Jérôme Berthier, Alexis Drouard, Mirel Birlan, J. Grice, R. Montaigut, J. His, L. Socha, Romain Fétick, Olivier Witasse, Pierre Vernazza, Thierry Fusco, Benoit Carry, F. Marchis, Doeon Kim, Toni Santana-Ros, Mikko Kaasalainen, Matti Viikinkoski, P. Sabin, M. Audejean, A. Marciniak, Myung-Jin Kim, Bin Yang, Agnieszka Kryszczyńska, François Colas, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institute of Astronomy [Prague], Charles University [Prague] (CU), Université Côte d'Azur, Observatoire de la Côte d'Azur, CNRS, Laboratoire Lagrange, Nice, France, Department of Earth, Atmospheric and Planetary Sciences [MIT, Cambridge] (EAPS), Massachusetts Institute of Technology (MIT), Tampere University of Technology [Tampere] (TUT), Search for Extraterrestrial Intelligence Institute (SETI), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Astronomical Institute of Romanian Academy, Romanian Academy, Adam Mickiewicz University in Poznań (UAM), Institut de Recherche en Horticulture et Semences (IRHS), Université d'Angers (UA)-AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Université de Liège, Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), California Institute of Technology (CALTECH), European Space Agency (ESA), TMT Observatory, The Open University [Milton Keynes] (OU), Department of Mathematics [Tampere], University of Maryland [College Park], University of Maryland System, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Sorbonne Université (SU)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Hospices Civils de Lyon (HCL), Research on Healthcare Performance (RESHAPE - Inserm U1290 - UCBL1), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM), Universidad de Alicante, Universitat de Barcelona (UB), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Observatoire de Chinon, Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Observatoire de Haute-Provence (OHP), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Geneva Observatory, University of Geneva [Switzerland], Université Cadi Ayyad [Marrakech] (UCA), Héritages et Constructions dans le Texte et l'Image (HCTI), Institut Brestois des Sciences de l'Homme et de la Société (IBSHS), Université de Brest (UBO)-Université de Brest (UBO)-Université de Bretagne Sud (UBS)-Université de Brest (UBO), Observatoire du Bois de Bardon, Association T60, Observatoire Midi-Pyrénées, Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Laboratory for Space Research [Hong Kong] (LSR), The University of Hong Kong (HKU), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Korea Astronomy and Space Science Institute (KASI), Okayama University, Chungbuk National University, Laboratoire d'analyse et de recherche en économie et finance internationales (Larefi), Université de Bordeaux (UB), Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Anunaki Observatory, Sanofi-Aventis R&D, SANOFI Recherche, Planetary Science Institute [Tucson] (PSI), Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Ministerio de Economía y Competitividad (España), Belgian Science Policy Office, National Science Foundation (US), Generalitat Valenciana, Université Côte d'Azur (UCA), Université d'Angers (UA)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-INSTITUT AGRO Agrocampus Ouest, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Agence Spatiale Européenne = European Space Agency (ESA), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Genève = University of Geneva (UNIGE), Université de Bretagne Sud (UBS)-Université de Brest (UBO)-Institut Brestois des Sciences de l'Homme et de la Société (IBSHS), Université de Brest (UBO), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France, Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Tampere University, and Computing Sciences
Subjects: asteroids, Rotation period, Surface (mathematics), Shell (structure), [SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], general [Minor planets, asteroids], Context (language use), Astrophysics, 01 natural sciences, 03 medical and health sciences, Física Aplicada, 0103 physical sciences, 111 Mathematics, observational [Methods], 010303 astronomy & astrophysics, 030304 developmental biology, Physics, Asteroids:general, 0303 health sciences, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Minor planets, techniques: high angular resolution, Astronomy and Astrophysics, 113 Computer and information sciences, asteroids: general, Bimodality, high angular resolution [Techniques], Density distribution, 115 Astronomy and space science, Space and Planetary Science, Asteroid, [SDU]Sciences of the Universe [physics], minor planets, methods: observational, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], general [Asteroids], high angular resolution, Shape analysis (digital geometry)
Abstract: Vernazza, P., et al., Until recently, the 3D shape, and therefore density (when combining the volume estimate with available mass estimates), and surface topography of the vast majority of the largest (D ≥ 100 km) main-belt asteroids have remained poorly constrained. The improved capabilities of the SPHERE/ZIMPOL instrument have opened new doors into ground-based asteroid exploration. Aims. To constrain the formation and evolution of a representative sample of large asteroids, we conducted a high-angular-resolution imaging survey of 42 large main-belt asteroids with VLT/SPHERE/ZIMPOL. Our asteroid sample comprises 39 bodies with D ≥ 100 km and in particular most D ≥ 200 km main-belt asteroids (20/23). Furthermore, it nicely reflects the compositional diversity present in the main belt as the sampled bodies belong to the following taxonomic classes: A, B, C, Ch/Cgh, E/M/X, K, P/T, S, and V. Methods. The SPHERE/ZIMPOL images were first used to reconstruct the 3D shape of all targets with both the ADAM and MPCD reconstruction methods.We subsequently performed a detailed shape analysis and constrained the density of each target using available mass estimates including our own mass estimates in the case of multiple systems. Results. The analysis of the reconstructed shapes allowed us to identify two families of objects as a function of their diameters, namely spherical and elongated bodies. A difference in rotation period appears to be the main origin of this bimodality. In addition, all but one object (216 Kleopatra) are located along the Maclaurin sequence with large volatile-rich bodies being the closest to the latter. Our results further reveal that the primaries of most multiple systems possess a rotation period of shorter than 6 h and an elongated shape (c=a ≤ 0.65). Densities in our sample range from ∼1.3 g cm-3 (87 Sylvia) to ∼4.3 g cm-3 (22 Kalliope). Furthermore, the density distribution appears to be strongly bimodal with volatile-poor (P ≥ 2.7 g cm-3) and volatile-rich (P ≤ 2.2 g cm-3) bodies. Finally, our survey along with previous observations provides evidence in support of the possibility that some C-complex bodies could be intrinsically related to IDP-like P- and D-type asteroids, representing different layers of a same body (C: core; P/D: outer shell). We therefore propose that P/ D-types and some C-types may have the same origin in the primordial trans-Neptunian disk., We warmly thank the ESO staff at Paranal and in particular Henri Boffin for providing us precious support and advice throughout the entire observing programme. P.V., A.D., M.F., L.J. and B.C. were supported by CNRS/INSU/PNP. The work of T.S-R. was carried out through grant APOSTD/2019/046 by Generalitat Valenciana (Spain). This work was supported by the MINECO (Spanish Ministry of Economy) through grant RTI2018-095076-B-C21 (MINECO/FEDER, UE). TRAPPIST project is funded by the Belgian Fund for Scientic Research (Fond National de la Recherche Scientique, FNRS) under the grant PDR T.0120.21. E.J. is a FNRS Senior Research Associate. F.M. is supported by the National Science Foundation under Grant No. 1743015.
Published: 2021

45. The metal-poor end of the Spite plateau. II. Detailed chemical investigation

Author: Matas Pinto, A., Spite, M., Caffau, E., Bonifacio, P., Sbordone, L., Sivarani, T., Steffen, M., Spite, F., Francois, P., Di Matteo, P., Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Indian Institute of Astrophysics (IIA), Leibniz Institute for Astrophysics Potsdam (AIP), and Université de Picardie Jules Verne (UPJV)
Subjects: formation -Line, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Stars, Astrophysics - Astrophysics of Galaxies, abundances -Galaxy, abundances -Population II -Line, Astrophysics - Solar and Stellar Astrophysics, Astrophysics of Galaxies (astro-ph.GA), evolution, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, profile -Galaxy
Abstract: International audience; Context. The study of old, metal-poor stars deepens our knowledge on the early stages of the universe. In particular, the study of these stars gives us a valuable insight into the masses of the first massive stars and their emission of ionising photons. Aims. We present a detailed chemical analysis and determination of the kinematic and orbital properties of a sample of 11 dwarf stars. These are metal-poor stars, and a few of them present a low lithium content. We inspected whether the other elements also present anomalies. Methods. We analysed the high-resolution UVES spectra of a few metal-poor stars using the Turbospectrum code to synthesise spectral lines profiles. This allowed us to derive a detailed chemical analysis of Fe
Published: 2021

46. An advanced multipole model for (216) Kleopatra triple system

Author: Laurent Jorda, Josef Hanus, François Colas, Alexis Drouard, J. Grice, Julie Castillo-Rogez, Patrick Michel, Philippe Lamy, Pierre Vernazza, Josef Ďurech, Miroslav Brož, Bin Yang, Matti Viikinkoski, Franck Marchis, Tadeusz Michalowski, Marin Ferrais, Fabrice Cipriani, Thierry Fusco, Nicolas Rambaux, Olivier Witasse, Przemyslaw Bartczak, Arthur Vigan, David Vokrouhlický, Emmanuel Jehin, E. Podlewska-Gaca, Toni Santana-Ros, Frédéric Vachier, M. Pajuelo, Paolo Tanga, S. Benseguane, Romain Fétick, Christophe Dumas, Grzegorz Dudziński, Mirel Birlan, Agnieszka Kryszczyńska, S. Fauvaud, Anna Marciniak, Benoit Carry, J. Berthier, Michael Marsset, Institute of Astronomy [Prague], Charles University [Prague] (CU), Search for Extraterrestrial Intelligence Institute (SETI), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Department of Earth, Atmospheric and Planetary Sciences [MIT, Cambridge] (EAPS), Massachusetts Institute of Technology (MIT), Tampere University of Technology [Tampere] (TUT), Universidad de Alicante. Departamento de Física, Ingeniería de Sistemas y Teoría de la Señal, Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, SETI Institute, Ondřejov Observatory of the Prague Astronomical Institute, Czech Academy of Sciences [Prague] (CAS), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire du Bois de Bardon, Astronomical Institute of Romanian Academy, Romanian Academy, Thirty Meter Telescope Observatory, Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), European Space Research and Technology Centre (ESTEC), Agence Spatiale Européenne = European Space Agency (ESA), DOTA, ONERA, Université Paris Saclay [Châtillon], ONERA-Université Paris-Saclay, School of Physical Sciences [Milton Keynes], Faculty of Science, Technology, Engineering and Mathematics [Milton Keynes], The Open University [Milton Keynes] (OU)-The Open University [Milton Keynes] (OU), PLANETO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Pontificia Universidad Católica del Perú = Pontifical Catholic University of Peru (PUCP), Universidad de Alicante, Institut de Ciencies del Cosmos (ICCUB), Universitat de Barcelona (UB), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Czech Science Foundation, Charles University (Czech Republic), National Science Foundation (US), National Aeronautics and Space Administration (US), Generalitat Valenciana, Ministerio de Ciencia, Innovación y Universidades (España), Fédération Wallonie-Bruxelles, and Belgian Science Policy Office
Subjects: 010504 meteorology & atmospheric sciences, fundamental parameters [Planets and satellites], Library science, FOS: Physical sciences, Astrophysics, 01 natural sciences, methods: numerical, Física Aplicada, 0103 physical sciences, Celestial mechanics, planets and satellites: fundamental parameters, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Physics, Earth and Planetary Astrophysics (astro-ph.EP), [PHYS]Physics [physics], numerical [Methods], [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Minor planets, Astronomy and Astrophysics, Astrometry, celestial mechanics, asteroids: individual: (216) Kleopatra, individual: (216) Kleopatra [Asteroids], Space and Planetary Science, individual: (216) Kleopatra [Minor planets, asteroids], minor planets, astrometry, TRAPPIST, Christian ministry, Earth and Planetary Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: [Aims] To interpret adaptive-optics observations of (216) Kleopatra, we need to describe an evolution of multiple moons orbiting an extremely irregular body and include their mutual interactions. Such orbits are generally non-Keplerian and orbital elements are not constants. [Methods] Consequently, we used a modified N-body integrator, which was significantly extended to include the multipole expansion of the gravitational field up to the order ℓ = 10. Its convergence was verified against the 'brute-force' algorithm. We computed the coefficients Cℓ m, Sℓ m for Kleopatra's shape, assuming a constant bulk density. For Solar System applications, it was also necessary to implement a variable distance and geometry of observations. Our χ2 metric then accounts for the absolute astrometry, the relative astrometry (second moon with respect to the first), angular velocities, and silhouettes, constraining the pole orientation. This allowed us to derive the orbital elements of Kleopatra's two moons. [Results] Using both archival astrometric data and new VLT/SPHERE observations (ESO LP 199.C-0074), we were able to identify the true periods of the moons, P1 = (1.822359 ± 0.004156) d, P2 = (2.745820 ± 0.004820) d. They orbit very close to the 3:2 mean-motion resonance, but their osculating eccentricities are too small compared to other perturbations (multipole, mutual), meaning that regular librations of the critical argument are not present. The resulting mass of Kleopatra, m1 = (1.49 ± 0.16) × 10-12 M· or 2.97 × 1018 kg, is significantly lower than previously thought. An implication explained in the accompanying paper is that (216) Kleopatra is a critically rotating body., Broz, M. et al., This work has been supported by the Czech Science Foundation through grant 21-11058S (M. Brož, D. Vokrouhlický), 20-08218S (J. Hanuš, J. Ďurech), and by the Charles University Research program No. UNCE/SCI/023. This material is partially based upon work supported by the National Science Foundation under Grant No. 1743015. P.V., A.D., M.F. and B.C. were supported by CNRS/INSU/PNP. M.M. was supported by the National Aeronautics and Space Administration under grant No. 80NSSC18K0849 issued through the Planetary Astronomy Program. The work of TSR was carried out through grant APOSTD/2019/046 by Generalitat Valenciana (Spain). This work was supported by the MINECO (Spanish Ministry of Economy) through grant RTI2018-095076-B-C21 (MINECO/FEDER, UE). The research leading to these results has received funding from the ARC grant for Concerted Research Actions, financed by the Wallonia-Brussels Federation. TRAPPIST is a project funded by the Belgian Fonds (National) de la Recherche Scientifique (F.R.S.-FNRS) under grant FRFC 2.5.594.09.F. TRAPPIST-North is a project funded by the University of Liège, and performed in collaboration with Cadi Ayyad University of Marrakesh. E. Jehin is a FNRS Senior Research Associate.
Published: 2021

47. TOI-220 b: a warm sub-Neptune discovered by TESS

Author: Petr Kabath, K. I. Collins, Florian Rodler, Christopher Stockdale, Sara Seager, T. Lopez, S. Hojjatpanah, Steve B. Howell, S. Sabotta, Nuno C. Santos, David Barrado, Enric Palle, Jan Subjak, M. Esposito, John P. Doty, Rafael Luque, Artyom Aguichine, Karen A. Collins, Olivier Demangeon, Vincent Van Eylen, J. R. De Medeiros, M. Fridlund, N. Scott, Susan E. Mullally, E. Goffo, J. F. Otegi, D. W. Latham, Oscar Barragán, Jon M. Jenkins, Rodrigo F. Díaz, L. M. Serrano, Stéphane Udry, P. Figueira, A. P. Hatzes, Vardan Adibekyan, Davide Gandolfi, P. Cortés-Zuleta, W. Fong, J. Cabrera, Peter J. Wheatley, Seth Redfield, Sascha Grziwa, A. Santerne, Benjamin F. Cooke, Sergio Hoyer, L. Acuña, Daniel Bayliss, J. D. Twicken, S. G. Sousa, A. Osborn, Joshua N. Winn, P. A. Strøm, Hans J. Deeg, E. Delgado Mena, H. P. Osborn, William D. Cochran, Rachel A. Matson, Elise Furlan, Jorge Lillo-Box, P. T. Boyd, John H. Livingston, I. C. Leão, James A. G. Jackman, Edward M. Bryant, François Bouchy, Magali Deleuil, O. Mousis, Jose-Manuel Almenara, Carina M. Persson, Judith Korth, Roland Vanderspek, Louise D. Nielsen, B. L. Canto Martins, David J. Armstrong, Eric L. N. Jensen, Emil Knudstrup, D. A. Yahalomi, Jeffrey C. Smith, S. C. C. Barros, Xavier Dumusque, Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Department of Brain and Behavioural Sciences, University of Pavia, European Southern Observatory (ESO), Instituto de Astrofísica e Ciências do Espaço (IASTRO), Research and Scientific Support Department, ESTEC (RSSD), European Space Research and Technology Centre (ESTEC), European Space Agency (ESA)-European Space Agency (ESA), Centro de Astrofísica da Universidade do Porto (CAUP), Universidade do Porto, Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre de Physique des Particules de Marseille (CPPM), Aix Marseille Université (AMU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Groupe de Recherche en Astronomie et Astrophysique du Languedoc (GRAAL), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Instituto de Astronomía y Física del Espacio [Buenos Aires] (IAFE), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET)-Universidad de Buenos Aires [Buenos Aires] (UBA), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Department of Geosciences and Natural Resource Management [Copenhagen] (IGN), Faculty of Science [Copenhagen], University of Copenhagen = Københavns Universitet (KU)-University of Copenhagen = Københavns Universitet (KU), Center for Space Research [Cambridge] (CSR), Massachusetts Institute of Technology (MIT), University of Warwick [Coventry], Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Department of Physics [Coventry], Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Institute for Marine and Antarctic Studies [Horbat] (IMAS), University of Tasmania [Hobart, Australia] (UTAS), PSE-ENV/SEDRE/LETIS, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), European Southern Observatory [Santiago] (ESO), Thüringer Landessternwarte Tautenburg (TLS), Astronomical Institute of the Czech Academy of Sciences (ASU / CAS), Czech Academy of Sciences [Prague] (CAS), Universidad de Córdoba [Cordoba], Instituto de Astrofisica de Canarias (IAC), Wesleyan University, Departamento de Física e Astronomia [Porto] (DFA/FCUP), Faculdade de Ciências da Universidade do Porto (FCUP), Universidade do Porto-Universidade do Porto, Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Pavia = University of Pavia (UNIPV), Agence Spatiale Européenne = European Space Agency (ESA)-Agence Spatiale Européenne = European Space Agency (ESA), Universidade do Porto = University of Porto, Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), University of Copenhagen = Københavns Universitet (UCPH)-University of Copenhagen = Københavns Universitet (UCPH), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Université de Genève = University of Geneva (UNIGE), Institute for Marine and Antarctic Studies [Hobart] (IMAS), Laboratoire d'étude et de recherche sur les transferts et les interactions dans les sous-sols (IRSN/PSE-ENV/SEDRE/LETIS), Service des déchets radioactifs et des transferts dans la géosphère (IRSN/PSE-ENV/SEDRE), Institut de Radioprotection et de Sûreté Nucléaire (IRSN)-Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Universidad de Córdoba = University of Córdoba [Córdoba], and Universidade do Porto = University of Porto-Universidade do Porto = University of Porto
Subjects: Dwarf star, Fundamental Parameters, 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Individual, Astrophysics, Photometric, planets and satellites: individual: TYC 8897-01263-1, 01 natural sciences, techniques: photometric, Planet, Neptune, 0103 physical sciences, techniques: radial velocities, Radial Velocities, planets and satellites: fundamental parameters, 010303 astronomy & astrophysics, TYC 8897-01263-1, 0105 earth and related environmental sciences, QB, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Astronomy and Astrophysics, Planets and Satellites, Radius, Planetary system, Stars, Exoplanet, Techniques, Radial velocity, 13. Climate action, Space and Planetary Science, echniques: photometric, stars: fundamental parameters, Planetary mass, Astrophysics - Earth and Planetary Astrophysics
Abstract: In this paper we report the discovery of TOI-220 $b$, a new sub-Neptune detected by the Transiting Exoplanet Survey Satellite (TESS) and confirmed by radial velocity follow-up observations with the HARPS spectrograph. Based on the combined analysis of TESS transit photometry and high precision radial velocity measurements we estimate a planetary mass of 13.8 $\pm$ 1.0 M$_{Earth}$ and radius of 3.03 $\pm$ 0.15 R$_{Earth}$, implying a bulk density of 2.73 $\pm$ 0.47 $\textrm{g cm}^{-3}$. TOI-220 $b$ orbits a relative bright (V=10.4) and old (10.1$\pm$1.4 Gyr) K dwarf star with a period of $\sim$10.69 d. Thus, TOI-220 $b$ is a new warm sub-Neptune with very precise mass and radius determinations. A Bayesian analysis of the TOI-220 $b$ internal structure indicates that due to the strong irradiation it receives, the low density of this planet could be explained with a steam atmosphere in radiative-convective equilibrium and a supercritical water layer on top of a differentiated interior made of a silicate mantle and a small iron core., Comment: Accepted for publication in MNRAS
Published: 2021

48. Sharpening quasar absorption lines with ESPRESSO: Temperature of warm gas at z ∼ 2, constraints on the Mg isotopic ratio, and structure of cold gas at z ∼ 0.5

Author: Noterdaeme, P., Balashev, S., Ledoux, C., Duchoquet, G., López, S., Telikova, K., Boissé, P., Krogager, J.-K., De Cia, A., Bergeron, J., Institut d'Astrophysique de Paris (IAP), Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Departamento de Astronomía y Astrofísica [Santiago], and Pontificia Universidad Católica de Chile (UC)
Subjects: quasars: absorption lines, quasars: individual: HE 0001−2340, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: International audience; Aims. We aim to study several key physical properties of quasar absorption-line systems that are subtly encoded in their absorption profiles and have not yet been thoroughly investigated or constrained.Methods. We analysed a high-resolution (R = 140 000) spectrum of the bright quasar HE 0001−2340 (zem = 2.26) obtained with ESPRESSO, which was recently installed at the Very Large Telescope. We analysed three systems at z = 0.45, z = 1.65, and z = 2.19 using multiple-component Voigt-profile fitting. We also compared our spectrum with those obtained with VLT/UVES, covering a total period of 17 years.Results. We disentangle turbulent and thermal broadening in many components spread over about 400 km s−1 in the z ≈ 2.19 sub-damped Lyman-α system. We derive an average temperature of 16 000 ± 1300 K, which is about twice the canonical value of the warm neutral medium in the Galactic interstellar medium (ISM). A comparison with other high-z, low-metallicity absorbers reveals an anti-correlation between gas temperature and total H I column density. Although requiring confirmation, this could be the first observational evidence of a thermal decrease with galactocentric distance; in other words, we may be witnessing a thermal transition between the circumgalactic medium and the cooler ISM. We revisit the Mg isotopic ratios at z = 0.45 and z = 1.65 and constrain them to be ξ = (26Mg + 25Mg)/24Mg < 0.6 and < 1.4 in these two systems, respectively. These values are consistent with the standard solar ratio; that is, we do not confirm strong enhancement of heavy isotopes previously inferred from UVES data. Finally, we confirm the partial coverage of the quasar emission-line region by a Fe I-bearing cloud in the z = 0.45 system and present evidence for velocity substructure of the gas that has Doppler parameters of the order of only ∼0.3 km s−1. This agrees well with the low kinetic temperature of T ∼ 100 K inferred from modelling of the gas physical conditions.Conslusions. This work demonstrates the unique insight provided by high-fidelity, high-resolution optical spectrographs on large telescopes when used to investigate the thermal state of the gas in and around galaxies as well as its spatial and velocity structure on small scales, and to constrain the associated stellar nucleosynthetic history.
Published: 2021

49. Weighing stars from birth to death: mass determination methods across the HRD

Author: Paul G. Beck, M. G. Pedersen, Maria Bergemann, Vincent Van Eylen, Ignasi Ribas, Conny Aerts, Ian Czekala, Nicolas Lodieu, Eline Tolstoy, Marie Martig, Nate Bastian, Benard Nsamba, Davide Gandolfi, Ana Escorza, Keivan G. Stassun, Aldo Serenelli, George C. Angelou, Y. Lebreton, J. M. Bestenlehner, A. Moya, Krešimir Pavlovski, Achim Weiss, M. M. Miller Bertolami, J. S. G. Mombarg, D. Baroch, Victor Silva Aguirre, Diane Feuillet, Fabian Schneider, Juan Carlos Morales, Konstanze Zwintz, Mark Gieles, Nancy Elias-Rosa, Léo Girardi, Pier-Emmanuel Tremblay, University of Leuven, University of Heidelberg, Ministerio de Ciencia, Innovación y Universidades (España), National Aeronautics and Space Administration (US), Alexander von Humboldt Foundation, European Commission, Royal Society (UK), German Research Foundation, Fundação para a Ciência e a Tecnologia (Portugal), Generalitat de Catalunya, Ministerio de Economía y Competitividad (España), Max Planck Society, Institute of Space Sciences [Barcelona] (ICE-CSIC), Spanish National Research Council [Madrid] (CSIC), Institut d'Estudis Espacials de Catalunya (IEEC-CSIC), Max Planck Institute for Astronomy (MPIA), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Institute of Astronomy [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Radboud university [Nijmegen], Liverpool John Moores University (LJMU), Karl-Franzens-Universität Graz, Instituto de Astrofisica de Canarias (IAC), University of Sheffield [Sheffield], University of California, INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Institut d'Astronomie et d'Astrophysique [Bruxelles] (IAA), Université libre de Bruxelles (ULB), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), University College of London [London] (UCL), Lund Observatory, Lund University [Lund], Università degli studi di Torino (UNITO), Universitat de Barcelona (UB), Institució Catalana de Recerca i Estudis Avançats (ICREA), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Universidad de La Laguna [Tenerife - SP] (ULL), Consejo Nacional de Investigaciones Científicas y Técnicas [Buenos Aires] (CONICET), Universidad Nacional de la Plata [Argentine] (UNLP), Universidad Politécnica de Madrid (UPM), University of Birmingham [Birmingham], Universidade do Porto, University of Zagreb, University of California [Santa Barbara] (UCSB), Heidelberger Institut für Theoretische Studien (H-ITS), Universität Heidelberg, Aarhus University [Aarhus], Vanderbilt University [Nashville], University of Groningen [Groningen], University of Warwick [Coventry], Universität Innsbruck [Innsbruck], A.S. acknowledges support from Grants ESP2017-82674-R and PID2019-108709GB-I00 (MICINN) and 2017-SGR-1131 (AGAUR). C.A., J.S.G.M., and M.G.P. received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (Grant agreement no. 670519: MAMSIE) and from the KU Leuven Research Council (grant C16/18/005: PARADISE). M.B. is supported through the Lise Meitner grant from the Max Planck Society and acknowledges support by the Collaborative Research centre SFB 881 (projects A5, A10), Heidelberg University, of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation). V.S.A. acknowledges support from the Independent Research Fund Denmark (Research grant 7027-00096B) and the Carlsberg foundation (Grant agreement CF19-0649). Funding for the Stellar Astrophysics Centre is provided by The Danish National Research Foundation (Grant agreement No. DNRF106). D.B., J.C.M., and I.R. acknowledge support from the Spanish Ministry of Science, Innovation and Universities (MICIU), and the Fondo Europeo de Desarrollo Regional (FEDER) through Grants ESP2016-80435-C2-1-R and PGC2018-098153-B-C33, as well as the support of the Generalitat de Catalunya (CERCA programme). N.B. gratefully acknowledge financial support from the Royal Society (University Research Fellowships) and from the European Research Council (ERC-CoG-646928, Multi-Pop). A.E. acknowledges support from the Research Foundation Flanders (FWO) under contract ZKD1501-00-W01 (Grant no. 792848). D.K.F. acknowledges funds from the Alexander von Humboldt Foundation in the framework of the Sofia Kovalevskaja Award endowed by the Federal Ministry of Education and Research and grant 2016-03412 from the Swedish Research Council. D.G. gratefully acknowledges financial support from the CRT foundation under Grant no. 2018.2323 'Gaseous or rocky? Unveiling the nature of small worlds'. L.G. acknowledges funding from LSST-Italy and from project MITiC 2015. N.L. was financially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under Grant number AYA2015-69350-C3-2-P. A.M. acknowledges funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 749962 (project THOT). B.N. is supported by Fundação para a Ciência e a Tecnologia (FCT, Portugal) under Grant PD/BD/113744/2015 from PhD::SPACE, an FCT PhD program, and by the Alexander von Humboldt Foundation. Further support from FEDER – Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 – Operacional Programme for Competitiveness and Internationalisation (POCI), and by Portuguese funds through FCT – Fundação para a Ciência e a Tecnologia in the framework of the Project POCI-01-0145-FEDER-030389 is also acknowledged. K.P. acknowledges support from the Croatian Science Foundation (HRZZ research Grant IP-2014-09-8656). P-E.T. has received funding from the European Research Council under the European Union’s Horizon 2020 research and innovation programme n. 677706 (WD3D). The authors thank our colleagues G. Bono, T.L. Campante, M.S. Cunha, P. Das, C. Johnston, F. Kiefer, P. Maxted, M.J.P.F.G. Monteiro, Th. Rodrigues, V. Schaffenroth, M. Vučković for helpful comments and useful discussions. This work presents results from the European Space Agency (ESA) space mission Gaia and from the American National Aeronautics and Space Administration (NASA) space missions Kepler and TESS., Radboud University [Nijmegen], University of California (UC), Università degli studi di Torino = University of Turin (UNITO), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Universidade do Porto = University of Porto, and University of California [Santa Barbara] (UC Santa Barbara)
Subjects: 010504 meteorology & atmospheric sciences, Astronomy, Astrophysics, 01 natural sciences, planetary systems [Stars], Range (statistics), stellar content [Galaxy], Astrophysics::Solar and Stellar Astrophysics, PRECISION RADIAL-VELOCITIES, 010303 astronomy & astrophysics, QC, Stars: fundamental parameters, Complement (set theory), QB, Physics, Sequence, Galaxy: stellar content, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], BROWN DWARF CANDIDATES, Methods: numerical, Asteroseismology, Exoplanet, Stars: evolution, LINED SPECTROSCOPIC BINARIES, Astrophysics - Solar and Stellar Astrophysics, Physical Sciences, INTERMEDIATE ASTROMETRIC DATA, Determination methods, Astrophysics::Earth and Planetary Astrophysics, Solar and stellar Astrophysics, FOS: Physical sciences, evolution [Stars], Astronomy & Astrophysics, fundamental parameters [Stars], binaries: eclipsing [Stars], Stars: planetary systems, 0103 physical sciences, GALACTIC GLOBULAR-CLUSTERS, Stars: binaries: eclipsing, Stellar archaeology, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Science & Technology, numerical [Methods], [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], FUNDAMENTAL STELLAR PARAMETERS, Astronomy and Astrophysics, TRANSITING EXTRASOLAR PLANETS, COMMON ENVELOPE BINARY, Astronomía, Stars, DETACHED ECLIPSING BINARIES, RED GIANT BRANCH, Space and Planetary Science
Abstract: The mass of a star is the most fundamental parameter for its structure, evolution, and final fate. It is particularly important for any kind of stellar archaeology and characterization of exoplanets. There exist a variety of methods in astronomy to estimate or determine it. In this review we present a significant number of such methods, beginning with the most direct and model-independent approach using detached eclipsing binaries. We then move to more indirect and model-dependent methods, such as the quite commonly used isochrone or stellar track fitting. The arrival of quantitative asteroseismology has opened a completely new approach to determine stellar masses and to complement and improve the accuracy of other methods. We include methods for different evolutionary stages, from the pre-main sequence to evolved (super)giants and final remnants. For all methods uncertainties and restrictions will be discussed. We provide lists of altogether more than 200 benchmark stars with relative mass accuracies between [0.3 , 2] % for the covered mass range of M∈[0.1,16]M⊙, 75 % of which are stars burning hydrogen in their core and the other 25 % covering all other evolved stages. We close with a recommendation how to combine various methods to arrive at a “mass-ladder” for stars., The authors are much indebted to all colleagues participating in the workshop, even though they were not involved in the textual contributions for this review paper. A.S. acknowledges support from Grants ESP2017-82674-R and PID2019-108709GB-I00 (MICINN) and 2017-SGR-1131 (AGAUR). C.A., J.S.G.M., and M.G.P. received funding from the European Research Council (ERC) under the European Union?s Horizon 2020 research and innovation programme (Grant agreement no.?670519: MAMSIE) and from the KU?Leuven Research Council (grant C16/18/005: PARADISE). M.B. is supported through the Lise Meitner grant from the Max Planck Society and acknowledges support by the Collaborative Research centre SFB 881 (projects A5, A10), Heidelberg University, of the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation). V.S.A. acknowledges support from the Independent Research Fund Denmark (Research grant 7027-00096B) and the Carlsberg foundation (Grant agreement CF19-0649). Funding for the Stellar Astrophysics Centre is provided by The Danish National Research Foundation (Grant agreement No.?DNRF106). D.B., J.C.M., and I.R. acknowledge support from the Spanish Ministry of Science, Innovation and Universities (MICIU), and the Fondo Europeo de Desarrollo Regional (FEDER) through Grants ESP2016-80435-C2-1-R and PGC2018-098153-B-C33, as well as the support of the Generalitat de Catalunya (CERCA programme). N.B. gratefully acknowledge financial support from the Royal Society (University Research Fellowships) and from the European Research Council (ERC-CoG-646928, Multi-Pop). A.E. acknowledges support from the Research Foundation Flanders (FWO) under contract ZKD1501-00-W01 (Grant no. 792848). D.K.F. acknowledges funds from the Alexander von Humboldt Foundation in the framework of the Sofia Kovalevskaja Award endowed by the Federal Ministry of Education and Research and grant 2016-03412 from the Swedish Research Council. D.G. gratefully acknowledges financial support from the CRT foundation under Grant no. 2018.2323 ?Gaseous or rocky? Unveiling the nature of small worlds ?. L.G. acknowledges funding from LSST-Italy and from project MITiC 2015. N.L. was financially supported by the Spanish Ministry of Economy and Competitiveness (MINECO) under Grant number AYA2015-69350-C3-2-P. A.M. acknowledges funding from the European Union?s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No?749962 (project THOT). B.N. is supported by Funda??o para a Ci?ncia e a Tecnologia (FCT, Portugal) under Grant PD/BD/113744/2015 from PhD::SPACE, an FCT PhD program, and by the Alexander von?Humboldt Foundation. Further support from FEDER ? Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 ? Operacional Programme for Competitiveness and Internationalisation (POCI), and by Portuguese funds through FCT ? Funda??o para a Ci?ncia e a Tecnologia in the framework of the Project POCI-01-0145-FEDER-030389 is also acknowledged. K.P. acknowledges support from the Croatian Science Foundation (HRZZ research Grant IP-2014-09-8656). P-E.T. has received funding from the European Research Council under the European Union?s Horizon 2020 research and innovation programme n.?677706 (WD3D). The authors thank our colleagues G.?Bono, T.L.?Campante, M.S.?Cunha, P. Das, C.?Johnston, F.?Kiefer, P.?Maxted, M.J.P.F.G.?Monteiro, Th.?Rodrigues, V. Schaffenroth, M. Vu?kovi? for helpful comments and useful discussions. This work presents results from the European Space Agency (ESA) space mission Gaia and from the American National Aeronautics and Space Administration (NASA) space missions Kepler and TESS.
Published: 2021

50. The Gaia RVS benchmark stars. I. Chemical inventory of the first sample of evolved stars and its Rb NLTE investigation

Author: F. Royer, Sergei M. Andrievsky, H. G. Ludwig, Luca Sbordone, P. Sartoretti, F. Spite, S. A. Korotin, G. Plum, V. V. Kovtyukh, P. Francois, Monique Spite, D. Katz, P. Di Matteo, O. Marchal, A. M. Matas Pinto, Alessio Mucciarelli, Piercarlo Bonifacio, Elisabetta Caffau, Matthias Steffen, R. Lallement, Laurent Chemin, M. Haywood, P. Panuzzo, F. Thévenin, Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Leibniz Institute for Astrophysics Potsdam (AIP), Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), European Southern Observatory [Santiago] (ESO), European Southern Observatory (ESO), Landessternwarte Königstuhl [ZAH] (LSW), Universität Heidelberg [Heidelberg], Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Caffau E., Bonifacio P., Korotin S.A., Francois P., Lallement R., Matas Pinto A.M., Di Matteo P., Steffen M., Mucciarelli A., Katz D., Haywood M., Chemin L., Sartoretti P., Sbordone L., Andrievsky S.M., Kovtyukh V.V., Spite M., Spite F., Panuzzo P., Royer F., Thevenin F., Ludwig H.-G., Marchal O., and Plum G.
Subjects: Metallicity, Context (language use), Astrophysics, 01 natural sciences, Spectral line, Dispersion relation, 0103 physical sciences, Galaxy formation and evolution, Astrophysics::Solar and Stellar Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Physics, Galaxy: evolution, Very Large Telescope, formation, Stars: abundances, Astronomy and Astrophysics, Stars, evolution -Galaxy, Radial velocity, Galaxy: abundance, abundances -Galaxy, Space and Planetary Science, Galaxy: formation, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Context. The Radial Velocity Spectrometer (RVS) on board the Gaia satellite is not provided with a wavelength calibration lamp. It uses its observations of stars with known radial velocity to derive the dispersion relation. To derive an accurate radial velocity calibration, a precise knowledge of the line spread function (LSF) of the RVS is necessary. Good-quality ground-based observations in the wavelength range of the RVS are highly desired to determine the LSF. Aims. Several radial velocity standard stars are available to the Gaia community. The highest possible number of calibrators will surely allow us to improve the accuracy of the radial velocity. Because the LSF may vary across the focal plane of the RVS, a large number of high-quality spectra for the LSF calibration may allow us to better sample the properties of the focal plane. Methods. We selected a sample of stars to be observed with UVES at the Very Large Telescope, in a setting including the wavelength range of RVS, that are bright enough to allow obtaining high-quality spectra in a short time. We also selected stars that lack chemical investigation in order to increase the sample of bright, close by stars with a complete chemical inventory. Results. We here present the chemical analysis of the first sample of 80 evolved stars. The quality of the spectra is very good, therefore we were able to derive abundances for 20 elements. The metallicity range spanned by the sample is about 1 dex, from slightly metal-poor to solar metallicity. We derived the Rb abundance for all stars and investigated departures from local thermodynamical equilibrium (NLTE) in the formation of its lines. Conclusions. The sample of spectra is of good quality, which is useful for a Gaia radial velocity calibration. The Rb NLTE effects in this stellar parameters range are small but sometimes non-negligible, especially for spectra of this good quality.
Published: 2021

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