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2,483 results on '"[PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]"'

1. Combining multi-spectral data with statistical and deep-learning models for improved exoplanet detection in direct imaging at high contrast

Author: Flasseur, Olivier, Bodrito, Théo, Mairal, Julien, Ponce, Jean, Langlois, Maud, Lagrange, Anne-Marie, 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), Models of visual object recognition and scene understanding (WILLOW), Département d'informatique - ENS Paris (DI-ENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria), Apprentissage de modèles à partir de données massives (Thoth), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Kuntzmann (LJK), Institut National de Recherche en Informatique et en Automatique (Inria)-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)-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), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS), Center for Data Science, New York University [New York] (NYU), NYU System (NYU)-NYU System (NYU), 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), 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, The work of OF, ML, and AML was supported in part by the EuropeanResearch Council (ERC) under the European Union’s Horizon 2020 researchand innovation program (COBREX, n° 885593). The work of TB and JP wassupported in part by the Inria/NYU collaboration, the Louis Vuitton/ENS chair on artificial intelligence and the French Agence Nationale de la Recherche (ANR) as part of the Investissements d’avenir program (PRAIRIE 3IAInstitute, n° 19-P3IA-0001). The work of JM was supported in part by theERC (SOLARIS, n° 714381) and by the ANR (3IA MIAI, n° 19-P3IA-0003)., ANR-19-P3IA-0001,PRAIRIE,PaRis Artificial Intelligence Research InstitutE(2019), ANR-19-P3IA-0003,MIAI,MIAI @ Grenoble Alpes(2019), European Project: 885593,COBREX, and European Project: 714381,H2020,SOLARIS(2017)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), FOS: Computer and information sciences, [PHYS]Physics [physics], Computer Science - Machine Learning, [STAT.AP]Statistics [stat]/Applications [stat.AP], Multi-variate data, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Matched filter, FOS: Physical sciences, Correlated data, [INFO.INFO-NE]Computer Science [cs]/Neural and Evolutionary Computing [cs.NE], Machine Learning (cs.LG), [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], [STAT]Statistics [stat], Detection, [STAT.ML]Statistics [stat]/Machine Learning [stat.ML], Supervised deep learning, Astrophysics - Instrumentation and Methods for Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Instrumentation and Methods for Astrophysics (astro-ph.IM), [STAT.ME]Statistics [stat]/Methodology [stat.ME], [PHYS.PHYS.PHYS-DATA-AN]Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an], Astrophysics - Earth and Planetary Astrophysics
Abstract: Exoplanet detection by direct imaging is a difficult task: the faint signals from the objects of interest are buried under a spatially structured nuisance component induced by the host star. The exoplanet signals can only be identified when combining several observations with dedicated detection algorithms. In contrast to most of existing methods, we propose to learn a model of the spatial, temporal and spectral characteristics of the nuisance, directly from the observations. In a pre-processing step, a statistical model of their correlations is built locally, and the data are centered and whitened to improve both their stationarity and signal-to-noise ratio (SNR). A convolutional neural network (CNN) is then trained in a supervised fashion to detect the residual signature of synthetic sources in the pre-processed images. Our method leads to a better trade-off between precision and recall than standard approaches in the field. It also outperforms a state-of-the-art algorithm based solely on a statistical framework. Besides, the exploitation of the spectral diversity improves the performance compared to a similar model built solely from spatio-temporal data., accepted to EUSIPCO 2023
Published: 2023

2. Methane as a dominant absorber in the habitable-zone sub-Neptune K2-18 b

Author: Bruno Bézard, Benjamin Charnay, Doriann Blain, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), 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 de Paris (UP)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Astrophysics::Galaxy Astrophysics, Physics::Atmospheric and Oceanic Physics, Astrophysics - Earth and Planetary Astrophysics
Abstract: In their Letter, Tsiaras et al. reported the detection of water vapour in the atmosphere of K2-18 b, an exoplanet of 7 to 10 Earth masses located in the habitable zone of an M-dwarf star. The detection is based on an absorption feature seen at 1.4 $\mu$m in observations of the transiting exoplanet with the Hubble Space Telescope/Wide Field Camera 3. We have simulated the mean temperature structure and composition of K2-18b using a radiative-convective equilibrium model and we present here the corresponding transit spectroscopy calculations. We argue that the reported absorption is most likely due to methane, a gas expected to be abundant in the hydrogen-helium atmosphere of cold sub-Neptunes. More generally, we show that the 1.4-$\mu$m absorption seen in transit spectra is not diagnostic of the presence of water vapour for sub-Neptunes having an effective temperature less than 600 K and that water vapour dominates over methane at this wavelength only at larger temperatures., Comment: This preprint has not undergone any post-submission improvements or corrections. The Version of Record of this article is published in Nature Astronomy (Matters Arising), and is available online at https://www.nature.com/articles/s41550-022-01678-z
Published: 2022

3. Kinetics and Branching for the Reactions of N2+ with C3H4 Isomers at Low Temperatures and Implications for Titan’s Atmosphere

Author: Ahmad Mortada, Sophie Carles, Sándor Demes, Baptiste Joalland, François Lique, Abdessamad Benidar, Panayotis Lavvas, Ludovic Biennier, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), ANR-14-CE33-0013, Agence Nationale de la Recherche, Centre National de la Recherche Scientifique, Commissariat ? l'énergie Atomique et aux énergies Alternatives, Centre National d'Etudes Spatiales, and ANR-14-CE33-0013,Anion Cos Chem,Explorer la Chimie et Spectroscopie des Anions Cosmiques(2014)
Subjects: [PHYS]Physics [physics], [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, temperature-dependent reactivity, reactive collisions, Atmospheric Science, uniform supersonic flows, astrochemistry, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Space and Planetary Science, Geochemistry and Petrology, planetary sciences, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Molecular physics
Abstract: International audience; The photoionization of N2 plays a key role in initiating the formation of complex organic molecules in the nitrogen-rich atmosphere of Saturn’s largest moon, Titan. To date, only a handful of laboratory studies have explored the reactivity of N2+ ions with hydrocarbons─limited to methane, acetylene, and ethylene─at the low temperatures relevant to Titan. Here, the rate coefficients, product identity, and branching ratios of the ion–molecule reactions of N2+ with C3H4 isomers, namely, propyne CH3CCH and allene CH2CCH2, were measured between 24 and 72 K in uniform supersonic flows. The rate coefficients are collisional and their temperature dependence is in remarkable agreement with capture models. The outcomes of both reactions are similar: they proceed primarily via dissociative charge transfer, leading to the formation of C3H3+ (main product, >70%) and C3H2+ (between 9 and 17%), whereas a second, nondissociative charge-transfer mechanism leading to C3H4+ becomes slightly more prominent as the temperature decreases (from 3 to 12%). C3H3+ is plausibly formed predominantly as the smallest aromatic cation, cyclopropenyl c-C3H3+, by following the lowest-energy pathway for the decomposition of allene and propyne cations. The measured rate coefficients and branching ratios were included in a photochemical model of Titan’s atmosphere. The results point toward a secondary role of N2+ + C3H4 reactive pathways in the production of c-C3H3+.
Published: 2022

4. deep PACO: Combining statistical models with deep learning for exoplanet detection and characterization in direct imaging at high contrast

Author: Flasseur, Olivier, Bodrito, Théo, Mairal, Julien, Ponce, Jean, Langlois, Maud, Lagrange, Anne-Marie, 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), Models of visual object recognition and scene understanding (WILLOW), Département d'informatique - ENS Paris (DI-ENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria), Apprentissage de modèles à partir de données massives (Thoth), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Kuntzmann (LJK), Institut National de Recherche en Informatique et en Automatique (Inria)-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)-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), Center for Data Science, New York University [New York] (NYU), NYU System (NYU)-NYU System (NYU), 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), 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, This project is supported in part by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (COBREX, grant agreement n° 885593). The work of TB and JP was supported in part by the Inria/NYU collaboration, the Louis Vuitton/ENS chair on artificial intelligence and the French government under management of Agence Nationale de la Recherche as part of the Investissements d’avenir program, reference ANR19-P3IA0001 (PRAIRIE 3IA Institute). The work of JM was supported in part by the ERC grant number 714381 (SOLARIS project) and by ANR 3IA MIAI@Grenoble-Alpes (ANR-19-P3IA-0003), ANR-19-P3IA-0001,PRAIRIE,PaRis Artificial Intelligence Research InstitutE(2019), ANR-19-P3IA-0003,MIAI,MIAI @ Grenoble Alpes(2019), European Project: 885593,COBREX, and European Project: 714381,H2020,SOLARIS(2017)
Subjects: [PHYS]Physics [physics], [STAT.AP]Statistics [stat]/Applications [stat.AP], Data reduction, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Deep learning, Exoplanet detection, [INFO.INFO-NE]Computer Science [cs]/Neural and Evolutionary Computing [cs.NE], [STAT.OT]Statistics [stat]/Other Statistics [stat.ML], Differential imaging, [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], [STAT]Statistics [stat], High-contrast imaging, Physics - Data Analysis, Statistics and Probability, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Instrumentation and Methods for Astrophysics, [STAT.ME]Statistics [stat]/Methodology [stat.ME], Instrumentation and Methods for Astrophysics (astro-ph.IM), Statistical method, [PHYS.PHYS.PHYS-DATA-AN]Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an], Data Analysis, Statistics and Probability (physics.data-an), Processing algorithm
Abstract: Direct imaging is an active research topic in astronomy for the detection and the characterization of young sub-stellar objects. The very high contrast between the host star and its companions makes the observations particularly challenging. In this context, post-processing methods combining several images recorded with the pupil tracking mode of telescope are needed. In previous works, we have presented a data-driven algorithm, PACO, capturing locally the spatial correlations of the data with a multi-variate Gaussian model. PACO delivers better detection sensitivity and confidence than the standard post-processing methods of the field. However, there is room for improvement due to the approximate fidelity of the PACO statistical model to the time evolving observations. In this paper, we propose to combine the statistical model of PACO with supervised deep learning. The data are first pre-processed with the PACO framework to improve the stationarity and the contrast. A convolutional neural network (CNN) is then trained in a supervised fashion to detect the residual signature of synthetic sources. Finally, the trained network delivers a detection map. The photometry of detected sources is estimated by a second CNN. We apply the proposed approach to several datasets from the VLT/SPHERE instrument. Our results show that its detection stage performs significantly better than baseline methods (cADI, PCA), and leads to a contrast improvement up to half a magnitude compared to PACO. The characterization stage of the proposed method performs on average on par with or better than the comparative algorithms (PCA, PACO) for angular separation above 0.5''., Submitted to Monthly Notices of the Royal Astronomical Society
Published: 2023

5. A 2022 τ-Herculid meteor cluster from an airborne experiment: automated detection, characterization, and consequences for meteoroids

Author: Vaubaillon, J., Loir, C., Ciocan, C., Kandeepan, M., Millet, M., Cassagne, A., Lacassagne, L., Da Fonseca, P., Zander, F., Buttsworth, D., Loehle, S., Toth, J., Gray, S., Moingeon, A., Rambaux, N., 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), Architecture et Logiciels pour Systèmes Embarqués sur Puce (ALSOC), LIP6, Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Epitech de Recherche en Informatique Appliquée (LERIA Epitech), Epitech Technology, University of Southern Queensland (USQ), Institut für Raumfahrtsysteme (IRS), Universität Stuttgart [Stuttgart], Comenius University in Bratislava, and Rocket Technologies International
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Comets: general, Space and Planetary Science, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, method: data analysis, [INFO.INFO-CV]Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV], Astronomy and Astrophysics, [INFO.INFO-ES]Computer Science [cs]/Embedded Systems, meteoroids, Astrophysics - Earth and Planetary Astrophysics
Abstract: Context. The existence of meteor clusters has long since been a subject of speculation and so far only seven events have been reported, among which two involve less than five meteors, and three were seen during the Leonid storms. Aims. The 1995 outburst of Comet 73P/Schwassmann-Wachmann was predicted to result in a meteor shower in May 2022. We detected the shower, proved this to be the result of this outburst, and detected another meteor cluster during the same observation mission. Methods. The {\tau}-Herculids meteor shower outburst on 31 May 2022 was continuously monitored for 4 hours during an airborne campaign. The video data were analyzed using a recently developed computer-vision processing chain for meteor real-time detection. Results. We report and characterize the detection of a meteor cluster involving 38 fragments, detected at 06:48 UT for a total duration of 11.3 s. The derived cumulative size frequency distribution index is relatively shallow: s = 3.1. Our open-source computer-vision processing chain (named FMDT) detects 100% of the meteors that a human eye is able to detect in the video. Classical automated motion detection assuming a static camera was not suitable for the stabilized camera setup because of residual motion. Conclusions. From all reported meteor clusters, we crudely estimate their occurrence to be less than one per million observed meteors. Low heliocentric distance enhances the probability of such meteoroid self-disruption in the interplanetary space., Comment: 6 pqges, 5 figures
Published: 2023

6. Dynamical detection of a companion driving a spiral arm in a protoplanetary disk

Author: Xie, Chen, Ren, Bin B., Dong, Ruobing, Choquet, Élodie, Vigan, Arthur, Gonzalez, Jean-François, Wagner, Kevin, Fang, Taotao, Ubeira-Gabellini, Maria Giulia, 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), 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, University of Victoria [Canada] (UVIC), 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), Steward Observatory, University of Arizona, Xiamen University, Dipartimento di Fisica (Milano), Università degli Studi di Milano = University of Milan (UNIMI), European Project: 101044152,ESCAPE, 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, ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), ANR-10-LABX-0066,LIO,Lyon Institute of Origins(2010), European Project: 101002188,PROTOPLANETS, European Project: 757561,HiRise, and European Project
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), planet-disk interactions, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], protoplanetary disks, FOS: Physical sciences, techniques: high angular resolution, techniques: image processing, stars: individual: HD 100453, Astrophysics - Earth and Planetary Astrophysics
Abstract: Radio and near-infrared observations have observed dozens of protoplanetary disks that host spiral arm features. Numerical simulations have shown that companions may excite spiral density waves in protoplanetary disks via companion-disk interaction. However, the lack of direct observational evidence for spiral-driving companions poses challenges to current theories of companion-disk interaction. Here we report multi-epoch observations of the binary system HD 100453 with the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) facility at the Very Large Telescope. By recovering the spiral features via robustly removing starlight contamination, we measure spiral motion across 4 yr to perform dynamical motion analyses. The spiral pattern motion is consistent with the orbital motion of the eccentric companion. With this first observational evidence of a companion driving a spiral arm among protoplanetary disks, we directly and dynamically confirm the long-standing theory on the origin of spiral features in protoplanetary disks. With the pattern motion of companion-driven spirals being independent of companion mass, here we establish a feasible way of searching for hidden spiral-arm-driving planets that are beyond the detection of existing ground-based high-contrast imagers., Accepted for publication in Astronomy and Astrophysics; 12 pages, 9 figures
Published: 2023

7. First observations of core-transiting seismic phases on Mars

Author: Jessica C. E. Irving, Vedran Lekić, Cecilia Durán, Mélanie Drilleau, Doyeon Kim, Attilio Rivoldini, Amir Khan, Henri Samuel, Daniele Antonangeli, William Bruce Banerdt, Caroline Beghein, Ebru Bozdağ, Savas Ceylan, Constantinos Charalambous, John Clinton, Paul Davis, Raphaël Garcia, null Domenico Giardini, Anna Catherine Horleston, Quancheng Huang, Kenneth J. Hurst, Taichi Kawamura, Scott D. King, Martin Knapmeyer, Jiaqi Li, Philippe Lognonné, Ross Maguire, Mark P. Panning, Ana-Catalina Plesa, Martin Schimmel, Nicholas C. Schmerr, Simon C. Stähler, Eleonore Stutzmann, Zongbo Xu, University of Bristol, School of Earth Sciences, Department of Geology, University of Maryland, Institute of Geophysics [ETH Zürich], Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), Royal Observatory of Belgium [Brussels] (ROB), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Jet Propulsion Laboratory (JPL), NASA-California Institute of Technology (CALTECH), Department of Earth, Planetary, and Space Sciences, University of California Los Angeles, Department of Applied Mathematics and Statistics & Department of Geophysics, Colorado School of Mines, Department of Electrical and Electronic Engineering, Imperial College London, South Kensington Campus, London, United Kingdom, Swiss Seismological Service [ETH Zurich] (SED), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)-Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), School of Earth Sciences [Bristol], University of Bristol [Bristol], Department of Applied Mathematics and Statistics & Department of Geophysics, Colorado School of Mines, Golden, CO, USA, Department of Geosciences, Virginia Tech, Blacksburg, VA, DLR-Berlin, Institute of Planetary Research, Germany, Department of Geology, University of Illinois Urbana-Champaign, Urbana, IL, USA, Geosciences Barcelona - CSIC, Barcelona, Spain, Department of Geology, University of Maryland, College Park, USA, S-CAPAD/DANTE, MAGIS, ANR-19-CE31-0008-08, and ANR-18-IDEX-0001
Subjects: Core evolution, Mars, Planetary structure, Multidisciplinary, marsquake, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], planetary structure, Impact, [SDU]Sciences of the Universe [physics], Mars InSight Seismology SKS Core, core evolution, Core, Seismology
Abstract: We present the first observations of seismic waves propagating through the core of Mars. These observations, made using seismic data collected by the InSight geophysical mission, have allowed us to construct the first seismically constrained models for the elastic properties of Mars' core. We observe core-transiting seismic phase SKS from two farside seismic events detected on Mars and measure the travel times of SKS relative to mantle traversing body waves. SKS travels through the core as a compressional wave, providing information about bulk modulus and density. We perform probabilistic inversions using the core-sensitive relative travel times together with gross geophysical data and travel times from other, more proximal, seismic events to seek the equation of state parameters that best describe the liquid iron-alloy core. Our inversions provide constraints on the velocities in Mars' core and are used to develop the first seismically based estimates of its composition. We show that models informed by our SKS data favor a somewhat smaller (median core radius = 1,780 to 1,810 km) and denser (core density = 6.2 to 6.3 g/cm3) core compared to previous estimates, with a P-wave velocity of 4.9 to 5.0 km/s at the core-mantle boundary, with the composition and structure of the mantle as a dominant source of uncertainty. We infer from our models that Mars' core contains a median of 20 to 22 wt% light alloying elements when we consider sulfur, oxygen, carbon, and hydrogen. These data can be used to inform models of planetary accretion, composition, and evolution., Proceedings of the National Academy of Sciences of the United States of America, 120 (18), ISSN:0027-8424, ISSN:1091-6490
Published: 2023
Full Text: View/download PDF

8. Gaia Data Release 3: the Solar System survey

Author: Tanga, P., Pauwels, T., Mignard, F., Muinonen, K., Cellino, A., David, P., Hestroffer, D., Spoto, F., Berthier, J., Guiraud, J., Roux, W., Carry, B., Delbo, M., Oro, A. Dell, Fouron, C., Galluccio, L., Jonckheere, A., Klioner, S. A., Lefustec, Y., Liberato, L., Ordénovic, C., Oreshina-Slezak, I., Penttilä, A., Pailler, F., Panem, Ch., Petit, J. -M., Portell, J., Poujoulet, E., Thuillot, W., van Hemelryck, E., Burlacu, A., Lasne, Y., Managau, S., 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), 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), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)
Subjects: [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract: Gaia DR3 article; The third data release by the Gaia mission of the European Space (DR3) is the first release to provide the community with a large sample of observations for more than 150 thousand Solar System objects, including asteroids and natural planetary satellites. The release contains astrometry (over 23 million epochs) and photometry, along with average reflectance spectra of 60518 asteroids and osculating elements. We present an overview of the procedures that have been implemented over several years of development and tests to process Solar System data at the level of accuracy that Gaia can reach. We illustrate the data properties and potential with some practical examples. In order to allow the users of DR3 to best exploit the data, we explain the assumptions and approaches followed in the implementation of the data processing pipeline for Solar System processing, and their effects in terms of data filtering, optimisation, and performances. We then test the data quality by analysing post-fit residuals to adjusted orbits, the capacity of detecting subtle dynamical effects (wobbling due to satellites or shape and Yarkovsky acceleration), and to reproduce known properties of asteroid photometry (phase curves and rotational light curves). The DR3 astrometric accuracy is a clear improvement over the data published in DR2, which concerned a very limited sample of asteroids. The performance of the data reduction is met, and is illustrated by the capacity of detecting milliarcsecond-level wobbling of the asteroid photocentre that is due to satellite or shape effects and contributes to Yarkovsky effect measurements. The third data release can in terms of data completeness and accuracy be considered the first full-scale realisation of the Solar System survey by Gaia.
Published: 2022

9. State-of-the-art laboratory experiments combined with quantum chemistry to study reactive ion-molecule collisions under interstellar conditions

Author: Demes, Sándor, Carles, Sophie, Mortada, Ahmad, Jara-Toro, Rafael, Joalland, Baptiste, Benidar, Abdessamad, Lique, François, Biennier, Ludovic, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), and PCMI (Programme National de Physique et Chimie du Milieu Interstellaire)
Subjects: [PHYS]Physics [physics], Reaction kinetics and dynamics, [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], Rate coefficients, Branching ratio, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Reaction Pathways, Quantum dynamics
Abstract: https://pcmi2022paris.sciencesconf.org/data/program/7_416206_Demes.pdf; International audience
Published: 2022

10. Effets de l'altération spatiale sur les astéroïdes primitifs. Etude par spectroscopie Infrarouge et microscopie électronique

Author: Rubino, Stefano, Institut d'astrophysique spatiale (IAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Matériaux et Transformations - UMR 8207 (UMET), Centrale Lille-Institut de Chimie du CNRS (INC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay, Rosario Brunetto, Hugues Leroux, and Ferenc Borondics
Subjects: Microscopy, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astéroïdes, Irradiation, Spectroscopie, Microscopie, Asteroids, Spectroscopy
Abstract: The study of small bodies in our solar system is fundamental for understanding its youth and evolution. These small "primitive" bodies are "undifferentiated" (they did not undergo phase density-separation, irreversibly altering their mineralogy). They have evolved very little since their birth, spurring a composition relatively close to that of the primordial protoplanetary disk. However, other processes, such as thermal alteration, aqueous alteration, shocks, or space-weathering can affect these bodies' surfaces. This is an issue, since remote-sensed data acquired while studying these bodies target these very surfaces. If these surfaces have been altered, they can induce a certain bias in the study of the composition of these small bodies. Therefore, it is paramount to understand the processes affecting the surface of primitive asteroids to correctly assess their composition.There are several ways to study the surface of primitive asteroids, such as remotely, from the Earth or from a satellite orbiting the body of interest, by acquiring spectroscopic data (gaining access to surface chemical and mineralogical composition). It is also possible to study these bodies in a laboratory environment, by working on analogous materials such as certain classes of "primitive" meteorites (carbonaceous chondrites), on terrestrial analogues (simpler to study than meteorites, but less closely related to extraterrestrial materials), or directly on extraterrestrial materials brought back by sample return missions.In this work, we replicate in a laboratory environment the effects of space weathering (SpWe) on the surface of primitive asteroids. More specifically, we focus on the effects of solar wind, the dominant SpWe process on "young" surfaces of the solar system. We have chosen three terrestrial minerals analogous to a "primitive" surface - three hydrated minerals (two serpentines and one saponite) - of which we have produced several pellets which have been bombarded using He and Ar ions, to investigate the effects of two different solar wind. In doing so, we made analogous materials of weathered primitive surface matter.These analogues were then characterized by infrared spectroscopy, from the visible to the far-infrared range, to study chemical changes prompted by ion bombardment. This was done by investigating how certain spectroscopic features - characteristic of hydrated silicates - changed upon ion-bombardment. We detected several effects, such as darkening in the visible range, visible slope reddening and bluing as well as a systematic shift towards longer wavelength affecting the position of several spectroscopic features.This spectroscopic characterization was followed by a study at smaller scale, using electron microscopy. We first characterized the surface of our weathered analogues using scanning electron microscopy, and then investigated the morphological and physicochemical changes taking place in the bombarded layer, at a nano-meter scale, using transmission electron microscopy. Strong vesiculation effects of various kinds were identified in the ion-bombarded amorphized layers, as well as textural changes and some elemental concentration evolutions (such as the loss of oxygen in the utmost top surfaces, preferential amorphization of magnesium, etc.).The coupling between these two techniques, IR spectroscopy and electron microscopy, acting at different scales, has allowed for a better understanding of SpWe effects on primitive bodies, and will be able to support current and future studies of primitive bodies, whether they are carried-out remotely or in a laboratory environment on returned samples.; L'étude des petits corps du système solaire est fondamentale pour la compréhension de sa jeunesse et de son évolution. Ces petits corps « primitifs » seraient « non-différenciés » (pas d'entrée en fusion et séparation des phases altérant la minéralogie). Ils n'auraient donc que très peu évolué depuis leur naissance, avec une composition étroitement liée à celle du disque proto-planétaire originel. Pourtant, d'autres processus, comme l'altération thermique, l'altération aqueuse, les chocs ou l'altération spatiale peuvent venir altérer la surface d'un corps primitif. Ceci est problématique, car les mesures acquises à distance de ces corps ont comme cible précisément leur surface. Si celle-ci est altérée, elle peut biaiser l'étude de la composition de ces petits corps. Il est donc important de comprendre les processus affectant la surface des astéroïdes primitifs, afin de pouvoir correctement interpréter leur composition.Il y a plusieurs façons d'étudier la surface d'astéroïdes primitifs, tel que à distance, depuis la Terre ou un satellite orbitant le corps d'intérêt, en acquérant des données de spectroscopie (composition chimique et minéralogique de surface). Il est aussi possible d'étudier ces corps en laboratoire, en travaillant sur des matériaux analogues comme certaines classes de météorites « primitives » (les chondrites carbonées), sur des analogues terrestres (plus simples à étudier que les météorites, mais moins étroitement liés à la matière extraterrestre), ou enfin sur de la matière extraterrestre rapportée par les missions de retour d'échantillons.Dans cette étude, nous nous sommes proposé d'étudier en laboratoire les effets de l'altération spatiale sur les surfaces d'astéroïdes primitifs. Plus précisément, cette étude est focalisée sur les effets du vent solaire, le processus dominant d'altération spatiale sur les surfaces « jeunes » du système solaire. Nous avons choisi trois minéraux terrestres analogues à une surface « primitive » - à savoir, trois minéraux hydratés (deux serpentines et une saponite) - dont nous avons produit des pastilles que nous avons bombardé avec des ions He et Ar, afin de simuler les effets de deux contributions différentes du vent solaire. Nous avons donc produit donc des analogues de surface primitive ayant subi de l'altération spatiale.Ces analogues ont ensuite été caractérisés par spectroscopie infrarouge, du visible jusqu'à l'Infrarouge lointain, afin d'étudier l'évolution chimique après bombardement ionique de nos échantillons, en suivant les changements induit par le bombardement sur des bandes spectroscopiques caractéristiques des minéraux hydratés dans l'IR, ainsi que sur l'évolution du continuum dans le visible. Nous avons détecté plusieurs effets, tels que l'assombrissement des spectres visible, rougissement et bleuissement des pentes spectrales selon l'échantillon ainsi qu'un déplacement systématique vers les grandes longueurs d'ondes de plusieurs bandes spectrales.Cette caractérisation spectroscopique a été suivie par une étude à plus petite échelle par microscopie électronique, dédiée à caractériser la surface de nos analogues altérés par microscopie électronique à balayage, et ensuite à étudier à l'échelle nanométrique les changements morphologiques et physico-chimiques ayant lieu dans la couche bombardée, par microscopie électronique à transmission. De forts effets de bullages de différents types ont été identifiés dans la couche amorphisée par bombardement ionique, ainsi que des changements de texture et certaines évolutions élémentaires (perte d'oxygène en surface, amorphisation préférentielle du magnésium, etc.).Le couplage entre ces deux techniques, spectroscopie IR et microscopie électronique, agissant à différentes échelles, a permis une meilleure compréhension des effets d'altérations spatiale sur les corps primitifs, et pourra prêter support à l'étude de ce type de surface, qu'elle soit menée à distance ou en laboratoire sur des matériaux récoltés.
Published: 2022

11. Volatile-rich comets ejected early on during Solar System formation

Author: Sarah E. Anderson, Jean-Marc Petit, Benoît Noyelles, Olivier Mousis, Philippe Rousselot, Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), OSU-THETA - Observatoire des Sciences de l'Univers - Terre Homme Environnement Temps Astronomie (OSU-THETA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Bourgogne (UB)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), 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: Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Space and Planetary Science, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [SDU]Sciences of the Universe [physics], comets: general, protoplanetary disks, FOS: Physical sciences, Astronomy and Astrophysics, comets: individual: C/2016 R2 PanSTARRS, Astrophysics - Earth and Planetary Astrophysics
Abstract: Comet C/2016 R2 PanSTARRS (hereafter C/2016 R2) presents an unusually high N2/CO abundance ratio, as well as a heavy depletion in H2O, making it the only known comet of its kind. Understanding its dynamical history is therefore of essential importance as it would allow us to gain a clearer understanding of the evolution of planetesimal formation in our Solar System. Two studies have independently estimated the possible origin of this comet from building blocks formed in a peculiar region of the protoplanetary disk, near the ice line of CO and N2. We intend to investigate the fates of objects formed from the building blocks in these regions. We hope to find a possible explanation for the lack of C/2016 R2-like comets in our Solar System. Using a numerical simulation of the early stages of Solar System formation, we track the dynamics of these objects in the Jumping Neptune scenario based on five different initial conditions for the protosolar disk. We integrate the positions of 250 000 planetesimals over time in order to analyze the evolution of their orbits and create a statistical profile of their expected permanent orbit. Results. We find that objects formed in the region of the CO- and N2- ice lines are highly likely to be sent towards the Oort Cloud or possibly ejected from the Solar System altogether on a relatively short timescale. In all our simulations, over 90% of clones formed in this region evolved into a hyperbolic trajectory, and between 1% and 10% were potentially captured by the Oort Cloud. The handful of comets that remained were either on long-period, highly eccentric orbits like C/2016 R2, or absorbed into the Edgeworth-Kuiper belt. Comets formed, 7 pages, 5 figures
Published: 2022

12. The 2022 encounter of the outburst material from comet 73P/Schwassmann–Wachmann 3

Author: Jeremie Vaubaillon, Quanzhi Ye, 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 Astronomy [Boston], and Boston University [Boston] (BU)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Space and Planetary Science, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Astronomy and Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics
Abstract: The encounter of the meteoric material from 73P/Schmassmann--Wachmann~3 produced during the comet's 1995 outburst in May 2022 provides a rare and valuable opportunity to understand a fragmenting comet. Here we explore various ejection configurations and their impact on the meteor outburst detected in the early hours of UT 2022 May 31. We show that the dust must have been ejected $\sim4$ to $5\times$ faster than calculated by water-ice sublimation model to best match the observed meteor activity. As only a small subset of particles with a narrow range of cross-section is expected to have reached the Earth, the large spread of meteor brightness likely indicates the presence of large but porous meteoroids in the trail. Other effects such as an enhanced lunar sodium tail and a visible glow from the meteoroid trail may have also occurred during the encounter., MNRAS in press
Published: 2022

13. Contribution of simultaneous PRIDE observations of JUICE and Clipper spacecraft to the Galilean satellites' ephemerides

Author: Fayolle, Marie, Dirkx, Dominic, Cimò, Giuseppe, Gurvits, Leonid, Lainey, Valery, Calvés, Guifré Molera, Pallichadath, Vidhya, Vermeersen, Bert, Visser, Pieter N. A. M., Delft University of Technology (TU Delft), Joint Institute for VLBI in Europe (JIVE ERIC), 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), and University of Tasmania [Hobart, Australia] (UTAS)
Subjects: [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract: International audience
Published: 2022

14. Whistler Waves Associated With Electron Beams in Magnetopause Reconnection Diffusion Regions

Author: Shan Wang, Naoki Bessho, Daniel B. Graham, Olivier Le Contel, Frederick D. Wilder, Yuri V. Khotyaintsev, Kevin J. Genestreti, Benoit Lavraud, Seung Choi, James L. Burch, Swedish Institute of Space Physics [Uppsala] (IRF), Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), 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), and Southwest Research Institute [San Antonio] (SwRI)
Subjects: Fusion, plasma och rymdfysik, Geophysics, Astronomi, astrofysik och kosmologi, Space and Planetary Science, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astronomy, Astrophysics and Cosmology, Fusion, Plasma and Space Physics
Abstract: Whistler waves are often observed in magnetopause reconnection associated with electron beams. We analyze seven MMS crossings surrounding the electron diffusion region (EDR) to study the role of electron beams in whistler excitation. Waves have two major types: (a) Narrow-band waves with high ellipticities and (b) broad-band waves that are more electrostatic with significant variations in ellipticities and wave normal angles. While both types of waves are associated with electron beams, the key difference is the anisotropy of the background population, with perpendicular and parallel anisotropies, respectively. The linear instability analysis suggests that the first type of wave is mainly due to the background anisotropy, with the beam contributing additional cyclotron resonance to enhance the wave growth. The second type of broadband waves are excited via Landau resonance, and as seen in one event, the beam anisotropy induces an additional cyclotron mode. The results are supported by particle-in-cell simulations. We infer that the first type occurs downstream of the central EDR, where background electrons experience Betatron acceleration to form the perpendicular anisotropy; the second type occurs in the central EDR of guide field reconnection. A parametric study is conducted with linear instability analysis. A beam anisotropy alone of above similar to 3 likely excites the cyclotron mode waves. Large beam drifts cause Doppler shifts and may lead to left-hand polarizations in the ion frame. Future studies are needed to determine whether the observation covers a broader parameter regime and to understand the competition between whistler and other instabilities.
Published: 2022

15. Exoplanet detection in angular differential imaging: combining a statistics-based learning with a deep-based learning for improved detections

Author: Flasseur, Olivier, Bodrito, Théo, Mairal, Julien, Ponce, Jean, Langlois, Maud, Lagrange, Anne-Marie, 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), Models of visual object recognition and scene understanding (WILLOW), Département d'informatique - ENS Paris (DI-ENS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-Inria de Paris, Institut National de Recherche en Informatique et en Automatique (Inria), Apprentissage de modèles à partir de données massives (Thoth), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire Jean Kuntzmann (LJK), Institut National de Recherche en Informatique et en Automatique (Inria)-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)-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), Center for Data Science, New York University [New York] (NYU), NYU System (NYU)-NYU System (NYU), 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), 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, This project is supported in part by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (COBREX, grant agreement n° 885593). The work of JP and TB was supported in part by the Inria/NYU collaboration, the Louis Vuitton/ENS chair on artificial intelligence and the French government under management of Agence Nationale de la Recherche as part of the 'Investissements d’avenir' program, reference ANR19-P3IA0001 (PRAIRIE 3IA Institute). The work of JM was supported in part by the ERC grant number 714381 (SOLARIS project) and by ANR 3IA MIAI@Grenoble Alpes (ANR-19-P3IA-0003), ANR-19-P3IA-0001,PRAIRIE,PaRis Artificial Intelligence Research InstitutE(2019), ANR-19-P3IA-0003,MIAI,MIAI @ Grenoble Alpes(2019), European Project: 885593,COBREX, and European Project: 714381,H2020,SOLARIS(2017)
Subjects: [PHYS]Physics [physics], [STAT.AP]Statistics [stat]/Applications [stat.AP], Data reduction, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Deep learning, Exoplanet detection, [INFO.INFO-NE]Computer Science [cs]/Neural and Evolutionary Computing [cs.NE], Differential imaging, [INFO.INFO-AI]Computer Science [cs]/Artificial Intelligence [cs.AI], [STAT]Statistics [stat], High-contrast imaging, [STAT.ML]Statistics [stat]/Machine Learning [stat.ML], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], [STAT.ME]Statistics [stat]/Methodology [stat.ME], Statistical method, [PHYS.PHYS.PHYS-DATA-AN]Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an], Processing algorithm
Abstract: International audience; Direct imaging is an active research topic in astronomy for the detection and the characterization of young sub- stellar objects. The very high contrast between the host star and its companions makes detection particularly challenging. In addition to the use of an extreme adaptive optics system and a coronagraph to strongly attenuate the starlight contamination, dedicated post processing methods combining several images recorded with the pupil tracking mode of the telescope are needed. In previous works, we have presented the PACO algorithm capturing the spatial correlations of the data with a multi-variate Gaussian model whose parameters are estimated in a data-driven fashion at the scale of a patch of a few tens of pixels. PACO is parameter free and delivers reliable detection confidences with an improved sensitivity compared to the standard methods of the field. However, there is a room for improvement in the detection sensitivity due to the approximate fidelity of the PACO statistical model with respect to the observations. We propose to combine the statistics-based model of PACO with a deep learning approach in a three- step algorithm. First, the data are centered and whitened locally using the PACO framework to improve the stationarity and the contrast in a preprocessing step. Second, a convolutional neural network is trained in a supervised fashion to detect the signature of synthetic sources in the preprocessed science data. The network is trained from scratch with a custom data augmentation strategy allowing to generate a large training set from a single spatio-temporal dataset. Finally, the trained network is applied to the preprocessed observations and delivers a detection map. We apply our method on eleven datasets from the VLT/SPHERE-IRDIS instrument and compare our method with PACO and other baselines of the field (cADI, PCA). Our results show that the proposed method performs on-par with or better than these algorithms, with a contrast improvement up to half a magnitude with respect to PACO.
Published: 2022

16. Multispectral image reconstruction of faint circumstellar environments from high contrast angular spectral differential imaging (ASDI) data

Author: Flasseur, Olivier, Thé, Samuel, Denis, Loïc, Thiébaut, Éric, Langlois, Maud, 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), Laboratoire Hubert Curien (LHC), and Institut d'Optique Graduate School (IOGS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS]Physics [physics], statistical method, [STAT.AP]Statistics [stat]/Applications [stat.AP], [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], regularized inverse problems, angular and spectral differential imaging, reconstruction algorithm, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [STAT]Statistics [stat], High-contrast imaging, circumstellar environment, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], [STAT.ME]Statistics [stat]/Methodology [stat.ME], [PHYS.PHYS.PHYS-DATA-AN]Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an]
Abstract: We recently proposed REXPACO, an algorithm for imaging circumstellar environments from high-contrast angular differential imaging (ADI) data. In the context of high-contrast imaging where the signal of interest is largely dominated by a nuisance term due to the stellar light leakages and the noise, our algorithm amounts to jointly estimating the object of interest and the statistics (mean and covariance matrix) of the nuisance component. In this contribution, we first extend the REXPACO algorithm by refining the statistical model of the nuisance component it embeds. Capitalizing on the improved robustness of this new method named robust REXPACO, we then show how it can be modified to deal with angular plus spectral differential imaging (ASDI) datasets. We apply our methods on several ADI and ASDI datasets from the IRDIS and IFS imagers of the VLT/SPHERE instrument and we show that the proposed algorithms significantly reduce the typical artifacts produced by stateof-the-art algorithms. By also taking into account the instrumental point spread function (PSF), our algorithms yield a deblurred estimate of the object of interest without the artifacts observed with other methods.
Published: 2022

17. Optimal multi-epoch combination of direct imaging observations for improved exoplanet detection

Author: Jules Dallant, Maud Langlois, Éric M. Thiébaut, Olivier Flasseur, 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), 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), and This work was supported by the Programme National de Plan´etologie (PNP) and the Action Sp´ecifique Haute R´esolution Angulaire (ASHRA) of CNRS/INSU co-funded by CNES.
Subjects: Direct imaging of exoplanets, Optimization Problem, High-contrast imaging, Keplerian motion, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Maximum likelihood ML estimation, Exoplanet detection, [PHYS.PHYS.PHYS-DATA-AN]Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an]
Abstract: International audience; Exoplanets detection by direct imaging remains one of the most challenging field of modern astronomy. The signal of the star can prevent the detection of orbiting companions in single datasets, but combining information from several observations helps boost the detection limits. We propose a new algorithm named PACOME, based on PACO’s approach, which optimally combines, in a maximum likelihood sense, multi-epoch datasets and improves the detection sensitivity of potential exoplanets by taking into account their orbital motions. The efficiency of the algorithm is tested on the well-known exoplanetary system 51 Eridani.
Published: 2022

18. Laboratory Experiments Confirm the Polarization of Auroral Emissions

Author: Slava Bourgeois, Léo Bosse, Jean Lilensten, Nicolas Gillet, Stéphane Curaba, Alain Delboulbé, Sylvain Rochat, 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 Grenoble Alpes (UGA), and Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Geophysics, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], General Earth and Planetary Sciences, ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2022

19. A transit timing variation observed for the long-period extremely low-density exoplanet HIP 41378 f

Author: J. I. Vines, Chris Stockdale, Samantha Thompson, Michaël Gillon, Sarah L. Casewell, Richard G. West, C. Murray, Akihiko Fukui, Julien de Wit, Stéphane Udry, Rosanna H. Tilbrook, David J. Armstrong, Douglas R. Alves, L. Delrez, Benjamin V. Rackham, Edward M. Bryant, Valerio Nascimbeni, David R. Anderson, Samuel Gill, Matthew R. Burleigh, Enric Palle, Elsa Ducrot, Maximiliano Moyano, P. P. Pedersen, Monika Lendl, Peter J. Wheatley, Molly R. Kosiarek, Michael R. Goad, James S. Jenkins, Thiam-Guan Tan, Brice-Olivier Demory, Jack S. Acton, Amaury H. M. J. Triaud, Daniel Bayliss, Prajwal Niraula, Beth A. Henderson, Tianjun Gan, Norio Narita, Caroline Odden, Bronwen J. Hardee, Alexandre Santerne, Philipp Eigmüller, Maximilian N. Günther, A. Burdanov, D. Sebastian, Benjamin F. Cooke, Supachai Awiphan, Francisco J. Pozuelos, Hannu Parviainen, Emmanuel Jehin, 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), University of Warwick [Coventry], Institut d'Optique Graduate School (IOGS), Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, National Astronomical Research Institute of Thailand (NARIT), Department of Physics and Astronomy [Leicester], University of Leicester, Cavendish Laboratory, University of Cambridge [UK] (CAM), Center for Space and Habitability (CSH), University of Bern, The University of Tokyo (UTokyo), Instituto de Astrofisica de Canarias (IAC), Space Sciences, Technologies and Astrophysics Research Institute (STAR), Universidad de Chile = University of Chile [Santiago] (UCHILE), Department of Astronomy and Astrophysics [UCSC Santa Cruz], University of California [Santa Cruz] (UC Santa Cruz), University of California (UC)-University of California (UC), Austrian Academy of Sciences (OeAW), Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Observatoire Astronomique de l'Université de Genève (ObsGE), and Université de Genève = University of Geneva (UNIGE)
Subjects: Extrasolare Planeten und Atmosphären, planets and satellites: detection, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Astrophysics, 01 natural sciences, techniques: photometric, Planet, Long period, 0103 physical sciences, Low density, Transit (astronomy), 10. No inequality, 010303 astronomy & astrophysics, Earth and Planetary Astrophysics (astro-ph.EP), Physics, planets and satellites: individual: HIP 41378 f, Transit-timing variation, 010308 nuclear & particles physics, 520 Astronomy, Astronomy and Astrophysics, Orbital period, Exoplanet, Photometry (astronomy), 13. Climate action, Space and Planetary Science, stars: individual: HIP 41378, Astrophysics - Earth and Planetary Astrophysics
Abstract: HIP 41378 f is a temperate $9.2\pm0.1 R_{\oplus}$ planet with period of 542.08 days and an extremely low density of $0.09\pm0.02$ g cm$^{-3}$. It transits the bright star HIP 41378 (V=8.93), making it an exciting target for atmospheric characterization including transmission spectroscopy. HIP 41378 was monitored photometrically between the dates of 2019 November 19 and November 28. We detected a transit of HIP 41378 f with NGTS, just the third transit ever detected for this planet, which confirms the orbital period. This is also the first ground-based detection of a transit of HIP 41378 f. Additional ground-based photometry was also obtained and used to constrain the time of the transit. The transit was measured to occur 1.50 hours earlier than predicted. We use an analytic transit timing variation (TTV) model to show the observed TTV can be explained by interactions between HIP 41378 e and HIP 41378 f. Using our TTV model, we predict the epochs of future transits of HIP 41378 f, with derived transit centres of T$_{C,4} = 2459355.087^{+0.031}_{-0.022}$ (May 2021) and T$_{C,5} = 2459897.078^{+0.114}_{-0.060}$ (Nov 2022)., Comment: Accepted for publication in MNRAS Letters. 6 pages, 2 figures
Published: 2021

20. Modeling of a two-phases system with phase change : application to the Earth inner core and transneptunian objects

Author: Métayer, Robin, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), 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)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Université de Lyon, Renaud Deguen, and Aurélie Guilbert-Lepoutre
Subjects: Two-phases mixture, Différenciation, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Compaction, Objets transneptuniens, Earth's inner core, Graine terrestre, Modèle d'évolution thermique, Planetology, Changement de phase, Planétologie, Transneptunian objects, Differentiation, Milieu biphasique, Phase change, Thermal evolution model
Abstract: At the center of the Earth, the core is mainly composed of an iron-nickel alloy, it is composed of a liquid outer core and a mainly solid inner core. This central sphere grows by crystallization of the liquid iron at the expense of the outer core. The boundary between inner and outer core is not sharp. This leads to the integration of liquid iron into the inner core, which is therefore a liquid-solid two-phase medium. Transneptunian objects are small bodies of the solar system whose orbits are mostly beyond the orbit of Neptune. They are icy bodies composed of ice and rocky dust. Due to radiogenic heating, the temperature rises in objects large enough to retain heat on geologic timescales, which can induce melting of water ice. This phase change would lead to the differentiation of these objects with a central rocky core surrounded by a less dense mantle of ice. This differentiation has never really been studied numerically and is generally considered immediate and complete whenever fusion is initiated. These very different objects are difficult to characterize geologically. Indeed, as the transneptunian objects are very far in the solar system, their observations remain relatively poor in information; the inner core is as inaccessible. It can only be probed with seismic waves that pass through. They are both objects made of 2 phases: liquid and solid, the evolution of this two-phases material depends on the possibility for these phases, of different densities, to separate, and on the change of phase as well: melting and crystallization. The separation of the liquid and solid phases of the same material is done by compaction of the solid and extraction of the liquid under gravity. This governs the current amount of liquid iron present in the inner core and also the differentiation of trans-Neptunian objects of sufficient size. Finally, these ferrous and aqueous two-phases systems both present a minor fraction of chemical elements acting as anti-freeze which motivate a similar phase change treatment. The development during this thesis of a two-phases model aims to characterize the compaction of the Earth's inner core and in particular the effects of the phase change sparsely studied until now, as well as the differentiation of trans-Neptunian objects. We present in this manuscript the physical model that we use as well as the adaptations that we established for these 2 distinct geological objects.; Le noyau, au centre de la Terre, est composé principalement d'un alliage de fer-nickel, il se décompose en une partie liquide externe et une sphère centrale majoritairement solide. Cette sphère centrale s'appelle la graine, elle croît par cristallisation du fer liquide au détriment du noyau externe. La frontière graine-noyau liquide n'est pas franche, ce qui conduit à l'intégration de fer liquide dans la graine qui est donc un milieux biphasique liquide-solide. Les objets transneptuniens sont des petits corps du système solaire dont l'orbite se situe majoritairement au-delà de celle de Neptune. Ce sont des corps glacés composés de glaces et de poussières de roches. L'augmentation de température d'origine radioactive sur les objets suffisamment gros pour retenir la chaleur aux échelles de temps géologiques peut induire la fusion de la glace d'eau. Ce changement de phase conduirait à la différenciation de ces objets avec un noyau central rocheux, entouré d'un manteau de glaces moins dense. Cette différenciation n'a jamais été vraiment étudiée numériquement et est généralement considérée immédiate et totale si la fusion est initiée. Ces objets très différents sont difficiles à caractériser géologiquement. En effet, alors que les objets transneptuniens sont très loin dans le système solaire et donc que leurs observations restent relativement pauvres en informations, la graine terrestre est tout aussi inaccessible. Celle-ci ne peut être sondée que via les ondes sismiques qui la traversent. Ce sont aussi conjointement des objets constitués de 2 phases~: liquide et solide, l'évolution de ce matériel biphasique dépend de la possibilité pour ces phases, de densités différentes, de se séparer, ainsi que du changement de phase~: fusion et cristallisation. La séparation des phases liquide et solide d'un même composé se fait par compaction du solide et extraction du liquide sous l'effet de la gravité. Cela gouverne la quantité actuelle de fer liquide présente dans la graine mais aussi la différenciation des objets transneptuniens de taille suffisante. Enfin, ces systèmes biphasiques ferreux et aqueux présentent chacun en minorité des espèces antigels qui motivent un traitement du changement de phase similaire. Le développement au cours de cette thèse d'un modèle biphasique a pour objectif de caractériser la compaction de la graine terrestre et en particulier les effets du changement de phase peu étudiés jusqu'ici, ainsi que la différenciation des objets transneptuniens. Nous présentons dans ce manuscrit le modèle physique que nous utilisons ainsi que les adaptations que nous avons établi pour ces 2 objets géologiques distincts.
Published: 2022

21. Global three-dimensional draping of magnetic field lines in Earth's magnetosheath from in-situ spacecraft measurements

Author: Bayane Michotte de Welle, Nicolas Aunai, Gautier Nguyen, Benoit Lavraud, Vincent Génot, Alexis Jeandet, Roch Smets, Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Délégation générale de l'armement (DGA), Ministère de la Défense, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), 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), and 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)
Subjects: [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract: Magnetic field draping occurs when the magnetic field lines frozen in a plasma flow wrap around a body or plasma environment. The draping of the interplanetary magnetic field (IMF) around the Earth's magnetosphere has been confirmed in the early days of space exploration. However, its global and three-dimensional structure is known from modeling only, mostly numerical. Here, this structure in the dayside of the Earth's magnetosheath is determined as a function of the upstream IMF orientation purely from in-situ spacecraft observations. We show the draping structure can be organized in three distinct regimes depending on how radial the upstream IMF is. Quantitative analysis demonstrates how the draping pattern results from the frozen-in condition with the magnetosheath flow, deflected around the magnetopause.
Published: 2022

22. Evolution of the reservoirs of volatiles in the protosolar nebula

Author: Antoine Schneeberger, Olivier Mousis, Artyom Aguichine, Jonathan I. Lunine, 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 Universitaire de France (IUF), Department of Astronomy [Ithaca], and Cornell University [New York]
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], protoplanetary disks, planets and satellites: composition, astrobiology, FOS: Physical sciences, Astronomy and Astrophysics, comets: individual: C/2016 R2 PanSTARR, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, planets and satellites: formation, solid state: volatile, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract: The supersolar abundances of volatiles observed in giant planets suggest that a compositional gradient was present at the time of their formation in the protosolar nebula. To explain this gradient, several studies have investigated the radial transport of trace species and the effect of icelines on the abundance profiles of solids and vapors formed in the disk. However, these models only consider the presence of solids in the forms of pure condensates or amorphous ice during the evolution of the protosolar nebula. They usually neglect the possible crystallization and destabilization of clathrates, along with the resulting interplay between the abundance of water and those of these crystalline forms. This study is aimed at pushing this kind of investigation further by considering all possible solid phases together in the protosolar nebula: pure condensates, amorphous ice, and clathrates. To this end, we used a one-dimensional (1D) protoplanetary disk model coupled with modules describing the evolution of trace species in the vapor phase, as well as the dynamics of dust and pebbles. Eleven key species are considered here, including H$_2$O, CO, CO$_2$, CH$_4$, H$_2$S, N$_2$, NH$_3$, Ar, Kr, Xe, and PH$_3$. Two sets of initial conditions are explored for the protosolar nebula. In a first scenario, the disk is initially filled with icy grains in the forms of pure condensates. In this case, we show that clathrates can crystallize and form enrichment peaks up to about ten times the initial abundances at their crystallization lines. In a second scenario, the volatiles were delivered to the protosolar nebula in the forms of amorphous grains. In this case, the presence of clathrates is not possible because there is no available crystalline water ice in their formation region. Enrichment peaks of pure condensates also form beyond the snowline up to about seven times the initial abundances., Comment: To be published in Astronomy & Astrophysics 19 pages, 11 figures
Published: 2023

23. A Radiolytic Origin of Red Organics at the Surface of the Arrokoth Trans-Neptunian Object

Author: Quirico, Eric, Augé, Basile, Bacmann, Aurore, Wolters, Cédric, Vuitton, Véronique, Gautier, Thomas, Flandinet, Laurène, Launois, Thibault, Jovanovic, Lora, Boduch, Philippe, Rothard, Hermann, Desage, Léopold, Faure, Alexandre, Schmitt, Bernard, Poch, Olivier, Grundy, William, Protopapa, Silvia, Fornasier, Sonia, Cooper, John F., Stern, S. Alan, 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, 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), Matériaux, Défauts et IRradiations (MADIR), Centre de recherche sur les Ions, les MAtériaux et la Photonique (CIMAP - UMR 6252), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Centre Interdisciplinaire de Recherche Ions Lasers (CIRIL), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Lowell Observatory [Flagstaff], Southwest Research Institute [Boulder] (SwRI), 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), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), and NASA Goddard Space Flight Center (GSFC)
Subjects: [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract: International audience; We report calculations and irradiation experiments that show that the red color of Arrokoth is the result of radiolytic processes by Galactic Cosmic Rays.
Published: 2022

24. 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

25. Night light polarization: modeling and observations of light pollution in the presence of aerosols and background skylight or airglow

Author: Leo Bosse, Jean Lilensten, Nicolas Gillet, Colette Brogniez, Olivier Pujol, Sylvain Rochat, Alain Delboulbé, Stéphane Curaba, M. G. Jonhsen, 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 Grenoble Alpes (UGA), Centre National de la Recherche Scientifique (CNRS), Laboratoire d’Optique Atmosphérique - UMR 8518 (LOA), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Tromsø Geophysical Observatory (TGO), The Arctic University of Norway [Tromsø, Norway] (UiT), and Bosse, Léo
Subjects: [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], [PHYS.ASTR.EP] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Atmospheric Science, Geophysics, [PHYS.ASTR.IM]Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Space and Planetary Science, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [INFO.INFO-MO] Computer Science [cs]/Modeling and Simulation, [PHYS.ASTR.IM] Physics [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, [PHYS.PHYS.PHYS-AO-PH] Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph]
Abstract: Aurorae and nightglow are faint atmospheric emissions visible during night-time at several wavelengths. These emissions have been extensively studied but their polarization remains controversial. A great challenge is that light pollution from cities and scattering in the lower atmosphere interfere with polarization measurements. We introduce a new polarized radiative transfer model able to compute the polarization measured by a virtual instrument in a given nocturnal environment recreating real world conditions (atmospheric and aerosol profiles, light sources with complex geometries, terrain obstructions).The model, based on single scattering equations in the atmosphere, is tested on a few simple configurations to assess the effect of several key parameters in controlled environments. {Our model constitutes a proof of concept for polarization measurements in nocturnal conditions, that calls for further investigations. In particular, we discuss how multiple-scattering (neglected in the present study) impacts our observations and their interpretation, and the future need for inter-calibrating the source and the polarimeter in order to optimally extract the information contained in this kind of measurements. The model outputs are compared to field measurements in five wavelengths. A convincing fit between the model predictions and observations is found in the three most constrained wavelengths despite the single scattering approximation. Several applications of our model are discussed that concern the polarization of aurorae, the impact of light pollution, or aerosols and air pollution measurements.
Published: 2022

26. Rossiter-McLaughlin detection of the 9-month period transiting exoplanet HIP41378 d

Author: S. Grouffal, A. Santerne, V. Bourrier, X. Dumusque, A. H. M. J. Triaud, L. Malavolta, V. Kunovac, D. J. Armstrong, O. Attia, S. C. C. Barros, I. Boisse, M. Deleuil, O. D. S. Demangeon, C. D. Dressing, P. Figueira, J. Lillo-Box, A. Mortier, D. Nardiello, N. C. Santos, S. G. Sousa, 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), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Instituto de Astrofísica e Ciências do Espaço (IASTRO), European Southern Observatory (ESO), Departement Physik [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Cavendish Laboratory, University of Cambridge [UK] (CAM), Faculdade de Ciências [Lisboa], and Universidade de Lisboa = University of Lisbon (ULISBOA)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), stars: individual: HIP41378, Space and Planetary Science, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], techniques: radial velocities, stars: activity, FOS: Physical sciences, Astronomy and Astrophysics, planetary systems, techniques: spectroscopic, Astrophysics - Earth and Planetary Astrophysics
Abstract: The Rossiter-McLaughlin (RM) effect is a method that allows us to measure the orbital obliquity of planets, which is an important constraint that has been used to understand the formation and migration mechanisms of planets, especially for hot Jupiters. In this paper, we present the RM observation of the Neptune-sized long-period transiting planet HIP41378 d. Those observations were obtained using the HARPS-N/TNG and ESPRESSO/ESO-VLT spectrographs over two transit events in 2019 and 2022. The analysis of the data with both the classical RM and the RM Revolutions methods allows us to confirm that the orbital period of this planet is 278 days and that the planet is on a prograde orbit with an obliquity of $\lambda$ = 57.1+26.4-17.9 degrees, a value which is consistent between both methods. HIP41378 d is the longest period planet for which the obliquity was measured so far. We do not detect transit timing variations with a precision of 30 and 100 minutes for the 2019 and 2022 transits, respectively. This result also illustrates that the RM effect provides a solution to follow-up from the ground the transit of small and long-period planets such as those that will be detected by the forthcoming ESA's PLATO mission., Comment: Accepted for publication in A&A
Published: 2022
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27. Effect of the UV dose on the formation of complex organic molecules in astrophysical ices: irradiation of methanol ices at 20 K and 80 K

Author: Laura I Tenelanda-Osorio, Alexis Bouquet, Thomas Javelle, Olivier Mousis, Fabrice Duvernay, Grégoire Danger, Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), 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 Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), ANR-16-CE29-0015,RAHIIA_SSOM,Analyses de résidus provenant d'analogues de glace interstellaire pour la compréhension de la formation de la matière organique du Système Solaire(2016), and ANR-12-JS08-0001,VAHIIA,Analyse de volatiles issus du réchauffement d'analogues de glaces interstellaires(2012)
Subjects: molecular processes, Space and Planetary Science, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], astrochemistry, [SDU]Sciences of the Universe [physics], ultraviolet: planetary systems, Astronomy and Astrophysics
Abstract: Methanol is a ubiquitous complex organic molecule (COM) in the interstellar medium, thought to be a precursor of larger COMs when it is submitted to different energetic processes, that can trigger chemical reactions in solid and gas phases. Using laboratory experiments, we report the characterization of the evolution of photoproducts generated by the UV irradiation of methanol ice at different UV doses and temperatures (20 and 80 K). We used gas chromatography coupled to mass spectrometry (GC-MS) to analyse the volatile organic compounds (VOCs) recovered during the warming of the photoprocessed methanol ice. We identified 21 molecules (with up to five carbon atoms, including alcohols, aldehydes, ketones, ester, and ethers) and followed their abundance as a function of the UV fluence and ice temperatures. With increasing UV fluence, an increase in the production of heavier COMs is observed, while species with 1 or 2 carbon atoms are depleted or do not increase. Species within a same chemical family show the same pattern of evolution, with heavier molecules present in smaller quantities. Ketones and esters are the chemical families that lead to more complex molecules and start forming at the earliest stages of irradiation. Their formation pathways are driven by radical recombinations with CO as the main building blocks. Aldehydes are formed before their alcohol counterparts, implying they do not form through alcohol dehydrogenation, but via radical recombination around HCO. Ethers seem to be the precursors of a large set of COMs, and alcohols present a steady profile throughout irradiation.
Published: 2022

28. The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 Micron Spectrum of the Planetary-Mass Companion VHS 1256-1257 b

Author: Brittany E. Miles, Beth A. Biller, Polychronis Patapis, Kadin Worthen, Emily Rickman, Kielan K. W. Hoch, Andrew Skemer, Marshall D. Perrin, Niall Whiteford, Christine H. Chen, B. Sargent, Sagnick Mukherjee, Caroline V. Morley, Sarah E. Moran, Mickael Bonnefoy, Simon Petrus, Aarynn L. Carter, Elodie Choquet, Sasha Hinkley, Kimberly Ward-Duong, Jarron M. Leisenring, Maxwell A. Millar-Blanchaer, Laurent Pueyo, Shrishmoy Ray, Steph Sallum, Karl R. Stapelfeldt, Jordan M. Stone, Jason J. Wang, Olivier Absil, William O. Balmer, Anthony Boccaletti, Mariangela Bonavita, Mark Booth, Brendan P. Bowler, Gael Chauvin, Valentin Christiaens, Thayne Currie, Camilla Danielski, Jonathan J. Fortney, Julien H. Girard, Carol A. Grady, Alexandra Z. Greenbaum, Thomas Henning, Dean C. Hines, Markus Janson, Paul Kalas, Jens Kammerer, Grant M. Kennedy, Matthew A. Kenworthy, Pierre Kervella, Pierre-Olivier Lagage, Ben W. P. Lew, Michael C. Liu, Bruce Macintosh, Sebastian Marino, Mark S. Marley, Christian Marois, Elisabeth C. Matthews, Brenda C. Matthews, Dimitri Mawet, Michael W. McElwain, Stanimir Metchev, Michael R. Meyer, Paul Molliere, Eric Pantin, Andreas Quirrenbach, Isabel Rebollido, Bin B. Ren, Glenn Schneider, Malavika Vasist, Mark C. Wyatt, Yifan Zhou, Zackery W. Briesemeister, Marta L Bryan, Per Calissendorff, Faustine Cantalloube, Gabriele Cugno, Matthew De Furio, Trent J. Dupuy, Samuel M. Factor, Jacqueline K. Faherty, Michael P. Fitzgerald, Kyle Franson, Eileen C. Gonzales, Callie E. Hood, Alex R. Howe, Adam L. Kraus, Masayuki Kuzuhara, Anne-Marie Lagrange, Kellen Lawson, Cecilia Lazzoni, Pengyu Liu, Jorge Llop-Sayson, James P. Lloyd, Raquel A. Martinez, Johan Mazoyer, Sascha P. Quanz, Jea Adams Redai, Matthias Samland, Joshua E. Schlieder, Motohide Tamura, Xianyu Tan, Taichi Uyama, Arthur Vigan, Johanna M. Vos, Kevin Wagner, Schuyler G. Wolff, Marie Ygouf, Xi Zhang, Keming Zhang, Zhoujian Zhang, University of California [Santa Cruz] (UC Santa Cruz), University of California (UC), University of Edinburgh, Departement Erdwissenschaften [ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Johns Hopkins University (JHU), Space Telescope Science Institute (STSci), University of California [San Diego] (UC San Diego), 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, 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), Université de Liège, Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-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), 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), 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), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), astro-ph.SR, Astrophysics - Solar and Stellar Astrophysics, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Space and Planetary Science, astro-ph.EP, FOS: Physical sciences, Astronomy and Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract: We present the highest fidelity spectrum to date of a planetary-mass object. VHS 1256 b is a $, Comment: Accepted ApJL Iterations of spectra reduced by the ERS team are hosted at this link: https://github.com/bemiles/JWST_VHS1256b_Reduction/tree/main/reduced_spectra
Published: 2022
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29. Augmenter la limite de détection des exoplanètes par combinaison optimale d'observations multi-époques en imagerie directe

Author: Dallant, Jules, Thiébaut, Éric, Langlois, Maud, Flasseur, Olivier, Dallant, Jules, 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), 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: [PHYS.ASTR.EP] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [PHYS.PHYS.PHYS-DATA-AN] Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an], [PHYS.PHYS.PHYS-DATA-AN]Physics [physics]/Physics [physics]/Data Analysis, Statistics and Probability [physics.data-an]
Abstract: International audience; La détection d'exoplanètes par imagerie directe est l'un des plus grands défis de l'astronomie moderne. L'intensité du signal de l'étoile peut empêcher la détection d'exoplanètes en orbite dans des données individuelles mais combiner les informations d'observations à plusieurs époques permet d'abaisser les limites de détection. Nous proposons un nouvel algorithme nommé PACOME, basée sur l'approche de PACO, combinant de manière optimale, au sens du maximum de vraisemblance, des jeux de données multi-époques et améliorant la sensibilité de détection d'éventuelles exoplanètes en tenant compte de leurs mouvements orbitaux. L'efficacité de l'algorithme est testée sur le système exoplanétaire HR 8799.
Published: 2022

30. Mitigating stellar activity jitter with different line lists for least-squares deconvolution: Analysis of a parametric and a randomised line selection

Author: Bellotti, S., Petit, P., Morin, J., Hussain, G. A. J., Folsom, C. P., Carmona, A., Delfosse, X., Moutou, C., Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), 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), Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM), 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, and ANR-18-CE31-0019,SPlaSH,Recherche de planètes habitables avec SPIRou(2018)
Subjects: techniques: polarimetric, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], stars: activity, techniques: radial velocities, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], methods: data analysis
Abstract: International audience; Context. Stellar activity limits the radial velocity (RV) search and characterisation of exoplanets, as it introduces spurious noise (called jitter) in the data sets and prevents the correct retrieval of a planetary signal. This is key for M dwarfs, considering that they manifest high activity levels and are primary targets for present and future searches of habitable Earth-like planets. To perform precise RV measurements, multi-line numerical techniques like cross-correlation and least-squares deconvolution (LSD) are typically employed.Aims. Effective filtering of activity is crucial to achieving the sensitivity required for small planet detections. Here we analyse the impact of selecting different line lists for LSD on the dispersion in our RV data sets, to identify the line list that most effectively reduces the jitter.Methods. We employ optical spectropolarimetric observations of the active M dwarf EV Lac collected with ESPaDOnS and NARVAL, and study two line down-selection approaches: a parametric method based on line properties (depth, wavelength, magnetic sensitivity) and a randomised algorithm that samples the line combination space. We test the latter further to find the line list that singles out the activity signal from other sources of noise, and on AD Leo and DS Leo to examine its consistency at mitigating jitter for different activity levels. The analysis is complemented with planetary injection tests.Results. The parametric selection yields a RV RMS reduction of less than 10%, while the randomised selection yields a systematic improvement (>50%) regardless of the activity level of the star examined. Furthermore, if activity is the dominant source of noise, this approach allows the construction of lists containing mainly activity-sensitive lines, which could be used to enhance the rotational modulation of the resulting data sets and determine the stellar rotation period more robustly. Finally, the output line lists allow the recovery of a synthetic planet (0.3–0.6 MJup on a 10 d orbit) in the presence of both moderate (20 m s−1 semi-amplitude) and high (200 m s−1) activity levels, without substantially affecting the planet signal (between 60 and 120 m s−1).
Published: 2022

31. Kelvin-Helmholtz instability and induced magnetic reconnection at the Earth's magnetopause: a 3D simulation based on satellite data

Author: M Faganello, M Sisti, F Califano, B Lavraud, Aix Marseille Université (AMU), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Physique des interactions ioniques et moléculaires (PIIM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and Dipartimento di Fisica 'E. Fermi', Universita Pisa, Pisa, Italy
Subjects: Kelvin-Helmholtz instability, Kelvin-Helmholtz instability Magnetic reconnection Earth’s magnetopause numerical simulation, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], nonlinear simulations, Condensed Matter Physics, [INFO.INFO-MO]Computer Science [cs]/Modeling and Simulation, Earth's magnetosphere, Physics::Geophysics, Nuclear Energy and Engineering, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], [SDU]Sciences of the Universe [physics], magnetic reconnection, Physics::Space Physics, Astrophysics::Earth and Planetary Astrophysics, Physics::Atmospheric and Oceanic Physics
Abstract: A 3D two-fluid simulation, using plasma parameters as measured by MMS on 8 September 2015, shows the nonlinear development of the Kelvin–Helmholtz instability at the Earth’s magnetopause. It shows extremely rich dynamics, including the development of a complex magnetic topology, vortex merging and secondary instabilities. Vortex induced and mid-latitude magnetic reconnection coexist and produce an asymmetric distribution of magnetic reconnection events. Off-equator reconnection exhibits a predominance of events in the Southern Hemisphere during the early nonlinear phase, as observed by satellites at the dayside magnetopause. The late nonlinear phase shows the development of vortex pairing for all latitudes while secondary Kelvin–Helmholtz instability develops only in the Northern Hemisphere, leading to an enhancement of the occurrence of off-equator reconnection there. Since vortices move tailward while evolving, this suggests that reconnection events in the Northern Hemisphere should dominate at the nightside magnetopause.
Published: 2022

32. 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

33. Planet Formation: Key Mechanisms and Global Models

Author: RAYMOND, Sean N., MORBIDELLI, Alessandro, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Raymond, Sean
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), [PHYS.ASTR.EP] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics - Solar and Stellar Astrophysics, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract: Models of planet formation are built on underlying physical processes. In order to make sense of the origin of the planets we must first understand the origin of their building blocks. This review comes in two parts. The first part presents a detailed description of six key mechanisms of planet formation: 1) The structure and evolution of protoplanetary disks 2) The formation of planetesimals 3) Accretion of protoplanets 4) Orbital migration of growing planets 5) Gas accretion and giant planet migration 6) Resonance trapping during planet migration. While this is not a comprehensive list, it includes processes for which our understanding has changed in recent years or for which key uncertainties remain. The second part of this review shows how global models are built out of planet formation processes. We present global models to explain different populations of known planetary systems, including close-in small/low-mass planets (i.e., super-Earths), giant exoplanets, and the Solar System's planets. We discuss the different sources of water on rocky exoplanets, and use cosmochemical measurements to constrain the origin of Earth's water. We point out the successes and failings of different models and how they may be falsified. Finally, we lay out a path for the future trajectory of planet formation studies., To appear in Lecture Notes of the 3rd Advanced School on Exoplanetary Science (Editors Mancini, Biazzo, Bozza, Sozzetti). 100 pages, 27 Figs
Published: 2022

34. A Positive Feedback Between Crustal Thickness and Melt Extraction for the Origin of the Martian Dichotomy

Author: Valentin Bonnet Gibet, Philippe Lognonné, Mark Wieczorek, Chloe Michaut, Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), 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)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Institut Universitaire de France (IUF), Ministère de l'Education nationale, de l’Enseignement supérieur et de la Recherche (M.E.N.E.S.R.), 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), Institut de Physique du Globe de Paris (IPGP (UMR_7154)), Institut national des sciences de l'Univers (INSU - CNRS)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), and ANR-19-CE31-0008,MAGIS,MArs Geophysical InSight(2019)
Subjects: Geophysics, Space and Planetary Science, Geochemistry and Petrology, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Earth and Planetary Sciences (miscellaneous), Mars, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Géodynamiques, Dichotomie nord/sud, [SDU.STU.MI]Sciences of the Universe [physics]/Earth Sciences/Mineralogy
Abstract: International audience; A North/South difference in crustal thickness is likely at the origin of the Martian dichotomy in topography. Recent crustal thickness maps were obtained by inversion of topography and gravity data seismically anchored at the InSight station. On average, the Martian crust is 51–71 km thick with a southern crust thicker by 18–28 km than the northern one. The origin of this crustal dichotomy is still debated although the hypothesis of a large impact is at present very popular. Here, we propose a new mechanism for the formation of this dichotomy that involves a positive feedback between crustal growth and mantle melting. As the crust is enriched in heat-producing elements, the lid of a one-plate planet is hotter and thinner where the crust is thicker, inducing a larger amount of partial melt below the lid and hence a larger rate of melt extraction and crustal growth. We first demonstrate analytically that larger wavelength perturbations, that is, hemispherical perturbations, grow faster because smaller wavelengths are more attenuated by thermal diffusion. We then use a parameterized thermal evolution model with a well-mixed mantle topped by two different lids characterized by their thermal structures and thicknesses to study the growth of the crust in the two hemispheres. Our results demonstrate that this positive feedback can generate a significant crustal dichotomy
Published: 2022

35. HD 207897 b:A dense sub-Neptune transiting a nearby and bright K-type star

Author: Andrew W. Mayo, Jorge Lillo-Box, George R. Ricker, C. Moutou, Stephen R. Kane, René Tronsgaard, Ashley Chontos, Allyson Bieryla, Karen A. Collins, Nicola Astudillo-Defru, Luc Arnold, Rafael Luque, Andrew W. Howard, Xavier Dumusque, S. G. Sousa, V. Bourrier, Erik Petigura, Joshua N. Winn, Magali Deleuil, Lauren M. Weiss, Enric Palle, Nuno C. Santos, Steven Giacalone, J. Rey, Damien Ségransan, Courtney D. Dressing, Paul A. Dalba, Arpita Roy, Jack Lubin, Sara Seager, Corey Beard, Natalie M. Batalha, Daniel Huber, C. E. Brasseur, T. Lopez, Howard Isaacson, Teo Mocnik, Jason D. Eastman, Peter Tenenbaum, N. Heidari, Michelle L. Hill, P. Cortés-Zuleta, O. Mousis, E. Delgado Mena, Diana Dragomir, D. W. Latham, François Bouchy, Aida Behmard, David Ehrenreich, P. A. Strøm, Fei Dai, F. Vakili, T. Forveille, Tansu Daylan, R. Vanderspek, Keivan G. Stassun, Alexandre Santerne, Melissa J. Hobson, X. Bonfils, Benjamin J. Fulton, G. Montagnier, M. Stalport, Francesco Pepe, Lars A. Buchhave, Flavien Kiefer, Nicholas Scarsdale, Lee J. Rosenthal, Vardan Adibekyan, Paul Robertson, Olivier Demangeon, J. M. Jenkins, A. Carmona, Nematollah Riazi, Stéphane Udry, Rodrigo F. Díaz, N. C. Hara, G. Gaisne, Thomas Barclay, Tara Fetherolf, X. Delfosse, L. Mignon, Sergio Hoyer, B. Courcol, J. Orell-Mique, S. Borgniet, Guillaume Hébrard, Ryan A. Rubenzahl, Lea A. Hirsch, S. Dalal, Ian J. M. Crossfield, Joseph M. Akana Murphy, L. Acuna, Isabelle Boisse, 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), Observatoire de Haute-Provence (OHP), Institut Pythéas (OSU PYTHEAS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), 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), Geneva Observatory, Université de Genève = University of Geneva (UNIGE), European Southern Observatory (ESO), Canada-France-Hawaii Telescope Corporation (CFHT), National Research Council of Canada (NRC)-Centre National de la Recherche Scientifique (CNRS)-University of Hawai'i [Honolulu] (UH), Departamento de Matemática y Fı́sica Aplicadas [Concepcion] (DMFA), Universidad Católica de la Santísima Concepción (UCSC), University of St Andrews [Scotland], Faculdade de Ciências [Lisboa], Universidade de Lisboa = University of Lisbon (ULISBOA), SwRI Planetary Science Directorate [Boulder], Southwest Research Institute [Boulder] (SwRI), 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, NASA Ames Research Center Cooperative for Research in Earth Science in Technology (ARC-CREST), NASA Ames Research Center (ARC), 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 Paris Cité (UPCité), Observatoire Astronomique de l'Université de Genève (ObsGE), National Space Institute [Lyngby] (DTU Space), Danmarks Tekniske Universitet = Technical University of Denmark (DTU), SETI Institute, Instituto de Astrofísica e Ciências do Espaço (IASTRO), MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology (MIT), Department of Astronomy, University of California, Genome Sequencing Center, University of Washington School of Medicine, Universidad de Chile = University of Chile [Santiago] (UCHILE), Departamento de Quimica Inorganica e Ingenieria Quimica (Cordoba, Spain), Universidad de Córdoba = University of Córdoba [Córdoba], Peoples Friendship University of Russia [RUDN University] (RUDN), Center for Astrophysics (emeritus), Harvard-Smithsonian, Cambridge, MA, USA, 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)-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)-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), Laboratoire de Didactique André Revuz (LDAR (EA_4434)), Université d'Artois (UA)-Université Paris Diderot - Paris 7 (UPD7)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Instituto de Astrofisica de Canarias (IAC), Universidad de La Laguna [Tenerife - SP] (ULL), Vanderbilt University [Nashville], SLAC National Accelerator Laboratory (SLAC), Stanford University, 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), Peyton Hall, Clarient Pathology Services, Partenaires INRAE, Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS), University of Geneva [Switzerland], Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut de Recherche pour le Développement (IRD), 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 Astrofísica da Universidade do Porto (CAUP), Universidade do Porto = University of Porto, 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), IFP Energies nouvelles (IFPEN), Center for Space Research [Cambridge] (CSR), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), 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), and ANR-18-CE31-0019,SPlaSH,Recherche de planètes habitables avec SPIRou(2018)
Subjects: Physics, Earth and Planetary Astrophysics (astro-ph.EP), education.field_of_study, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 010308 nuclear & particles physics, Population, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Radius, Planetary system, Star (graph theory), 01 natural sciences, Exoplanet, Radial velocity, 13. Climate action, Space and Planetary Science, Planet, Neptune, 0103 physical sciences, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], education, 010303 astronomy & astrophysics, QB, Astrophysics - Earth and Planetary Astrophysics
Abstract: We present the discovery and characterization of a transiting sub-Neptune orbiting with a 16.20 day period around a nearby (28 pc) and bright(V=8.37) K0V star HD207897 (TOI-1611). This discovery is based on photometric measurements from the Transiting Exoplanet Survey Satellite(TESS) mission and radial velocity (RV) observations from the SOPHIE, Automated Planet Finder (APF) and HIRES high precision spectrographs. We used EXOFASTv2 for simultaneously modeling the parameters of the planet and its host star, combining photometric and RV data to determine the planetary system parameters. We show that the planet has a radius of 2.50+/-0.08 RE and a mass of either 14.4+/-1.6 ME or 15.9+/-1.6 ME with nearly equal probability; the two solutions correspond to two possibilities for the stellar activity period. Hence, the density is either 5.1+/-0.7 g cm^-3 or 5.5^{+0.8}_{-0.7} g cm^-3, making it one of the relatively rare dense sub-Neptunes. The existence of such a dense planet at only 0.12 AU from its host star is unusual in the currently observed sub-Neptune (2, Comment: 18 pages, 12 figures, 6 tables; accepted for publication in the A&A journal; comments welcome
Published: 2022

36. Massive Multi‐Mission Statistical Study and Analytical Modeling of the Earth's Magnetopause: 4. On the Near‐Cusp Magnetopause Indentation

Author: G. Nguyen, N. Aunai, B. Michotte de Welle, A. Jeandet, B. Lavraud, D. Fontaine, Délégation générale de l'armement (DGA), Ministère de la Défense, Laboratoire de Physique des Plasmas (LPP), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École polytechnique (X)-Sorbonne Université (SU)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), 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), and 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)
Subjects: Geophysics, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Space and Planetary Science, [PHYS.PHYS.PHYS-SPACE-PH]Physics [physics]/Physics [physics]/Space Physics [physics.space-ph]
Abstract: International audience; The shape and location of the magnetopause current sheet in the near-cusp region is still a debated question. Over time, several observations led to contradictory conclusions regarding the presence of an indentation of the magnetopause in that region. As a result several empirical models consider the surface is indented in that region, while some others do not. To tackle this issue, we fit a total of 17,230 magnetopause crossings to various indented and non-indented analytical models. The results show that while all models describe the magnetopause position and shape equivalently far from the cusp region, the non-indented version over-estimate the radial position of the near-cusp magnetopause. Among indented models, we show that the one designed from non-linearmagneto hydrodynamic simulations fits well the near-cusp magnetopause location, while the other underestimate its position probably because their design was possibly based on magnetopause crossing catalogs that contain cusp inner boundary crossings.
Published: 2022

37. PECULIAR COMETS EJECTED EARLY IN SOLAR SYSTEM FORMATION

Author: Sarah E. Anderson, Jean-Marc Petit, Benoît Noyelles, Olivier Mousis, Philippe Rousselot, Petit, Jean-Marc, Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), 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: [PHYS.ASTR.EP] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP]
Abstract: International audience; Introduction: Radio observations of the long period comet C/2016 R2 (PanSTARRS), hereafter R2, revealed that it was a CO-rich comet remarkably depleted in water [1]. Further, the spectrum was dominated by bands of CO + as well as N2 + , the latter of which never being seen in such abundance in comets before [2][3]. This CO and N2-rich and water-poor composition, along with none of the usual neutrals seen in most cometary spectra, makes R2 a unique and intriguing specimen. Understanding the dynamical history of this comet is thus of essential importance to understanding the timeline of planetesimal formation in our solar system. However, tracking such a small object backward with any degree of certainty is made impossible by the inherent chaotic nature of its motion due to frequent close encounters with the gas giants. Alternative measures must be employed in order to determine where this unique comet originated from. Two studies have independently estimated the possible origin of this comet from building blocks formed in a peculiar region in the protoplanetary disk, near the ice line of CO and N2. By evaluating the radial transport of volatiles in the Protoplanetary Disk (PPD), Mousis (2021) [4] found that R2's peculiar N2/CO ratio could be replicated by agglomeration from particles near the N2 and CO icelines, i.e. within the 10-15 au region. Meanwhile, the CO/H2O ratio would remain deeply depleted inward of the CO iceline (see Figure 1). Similarly, Price (2021) [5] model the effect of drifting solid material in the PPD and find that the ideal location for the objects to form is beyond CO iceline. However, this would indicate that more CO rich comets should exist than have previously been observed. Methods: Here we explore the potential fates of comets formed from these building blocks using a numerical simulation of early solar system formation and tracking the dynamics of these objects in the Jumping Neptune scenario Nesvorny (2015) [6]. We start with five planets: Jupiter, Saturn, and three ice giants, as described by Deienno et al (2017) [7]. The planetary evolutions are selected to meet criteria of similarity with the solar system today, among which having four planets and Jupiter and Saturn having suffered a rapid separation of their orbits due to an instability while crossing a mean motion resonance. We fill the disk between 4 au to avoid the inner solar system, and 50 au with massless comet facsimiles or 'clones'. We then use a modified SWIFT numerical
Published: 2022

38. SPIRou: NIR velocimetry and spectropolarimetry at the CFHT

Author: L. Parès, M. J. Hobson, F. Dolon, Marielle Lacombe, C. Moutou, Gregory Barrick, S Macdonald, Tom Ray, Pascal Fouqué, B Dubois, S. H. P. Alencar, Xavier Bonfils, John Pazder, Francois Wildi, Étienne Artigau, J Dunn, E Carrié, M Larrieu, D. Kouach, P. Figueira, Bruno Castilho, Tom Benedict, Y Micheau, Stéphane Udry, Simon Thibault, René Doyon, V. Reshetov, Bruno Chazelas, Eder Martioli, Chi-Hung Yan, Nuno C. Santos, Isabelle Boisse, Oscar F. Hernández, Neil Cook, P. Rabou, François Moreau, C Feugeade, R. Sottile, Tom Vermeulen, Leslie Saddlemyer, François Bouchy, Jerome Bouvier, S. Perruchot, G Gallou, Shiang-Yu Wang, F. Henault, Philippe Vallée, Julien Morin, Sébastien Baratchart, A. Carmona, X. Delfosse, M Dupieux, Nicolas Striebig, Marc Baril, Luc Arnold, Z Challita, Francesco Pepe, I Wevers, J.-F. Donati, Lison Malo, Guillaume Hébrard, C Usher, H Valentin, D Kerley, Tilo Steinmetz, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), 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), 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), Departement de physique and Observatoire du Mont Megantic, Université de Montréal (UdeM), 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, Département de Physique [Montréal], Géosciences Environnement Toulouse (GET), Toulouse Biotechnology Institute (TBI), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), ANR-18-CE31-0019,SPlaSH,Recherche de planètes habitables avec SPIRou(2018), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse 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)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), 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), 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), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), 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)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Météo France-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)
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], 01 natural sciences, law.invention, 010309 optics, Telescope, Planet, law, techniques: radial velocities, stars: magnetic fields, 0103 physical sciences, planetary systems, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, instrumentation: spectrographs, Physics, stars: formation, instrumentation: polarimeters, Astronomy, Astronomy and Astrophysics, Velocimetry, Planetary system, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Exoplanet, Stars, Astrophysics - Solar and Stellar Astrophysics, [SDU]Sciences of the Universe [physics], Space and Planetary Science, Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: This paper presents an overview of SPIRou, the new-generation near-infrared spectropolarimeter / precision velocimeter recently installed on the 3.6-m Canada-France-Hawaii Telescope (CFHT). Starting from the two main science goals, namely the quest for planetary systems around nearby M dwarfs and the study of magnetized star / planet formation, we outline the instrument concept that was designed to efficiently address these forefront topics, and detail the in-lab and on-sky instrument performances measured throughout the intensive testing phase that SPIRou was submitted to before passing the final acceptance review in early 2019 and initiating science observations. With a central position among the newly started programmes, the SPIRou Legacy Survey (SLS) Large Programme was allocated 300 CFHT nights until at least mid 2022. We also briefly describe a few of the first results obtained in the various science topics that SPIRou started investigating, focusing in particular on planetary systems of nearby M dwarfs, transiting exoplanets and their atmospheres, magnetic fields of young stars, but also on alternate science goals like the atmospheres of M dwarfs and the Earth's atmosphere. We finally conclude on the essential role that SPIRou and the CFHT can play in coordination with forthcoming major facilities like the JWST, the ELTs, PLATO and ARIEL over the decade., Comment: MNRAS, in press (20 pages, 18 figures, 1 table)
Published: 2020

39. The origins of nearly coplanar, non-resonant systems of close-in super-Earths

Author: Sean N. Raymond, Leandro Esteves, Bertram Bitsch, André Izidoro, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universidade Estadual Paulista (Unesp), Rice University, Cnrs, and Max-Planck-Institut für Astronomie
Subjects: 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Protoplanetary discs, FOS: Physical sciences, Astrophysics, 01 natural sciences, Instability, Planet, 0103 physical sciences, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Degree (graph theory), Scattering, Resonance, Astronomy and Astrophysics, Coplanarity, Compact space, Mean motion, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, formation [Planets and satellites], Astrophysics - Earth and Planetary Astrophysics
Abstract: Some systems of close-in "super-Earths" contain five or more planets on non-resonant but compact and nearly coplanar orbits. The Kepler-11 system is an iconic representative of this class of system. It is challenging to explain their origins given that planet-disk interactions are thought to be essential to maintain such a high degree of coplanarity, yet these same interactions invariably cause planets to migrate into chains of mean motion resonances. Here we mine a large dataset of dynamical simulations of super-Earth formation by migration. These simulations match the observed period ratio distribution as long as the vast majority of planet pairs in resonance become dynamically unstable. When instabilities take place resonances are broken during a late phase of giant impacts, and typical surviving systems have planet pairs with significant mutual orbital inclinations. However, a subset of our unstable simulations matches the Kepler-11 system in terms of coplanarity, compactness, planet-multiplicity and non-resonant state. This subset have dynamical instability phases typically much shorter than ordinary systems. Unstable systems may keep a high degree of coplanarity post-instability if planets collide at very low orbital inclinations ($\lesssim1^\circ$) or if collisions promote efficient damping of orbital inclinations. If planetary scattering during the instability takes place at low orbital inclinations ($\text{i}\lesssim1^\circ$), orbital inclinations are barely increased by encounters before planets collide.When planetary scattering pumps orbital inclinations to higher values ($\gtrsim 1^\circ$) planets tend to collide at higher mutual orbital inclinations, but depending on the geometry of collisions mergers' orbital inclinations may be efficiently damped. Each of these formation pathways can produce analogues to the Kepler-11 system., Comment: Accepted by MNRAS, 9 pages, 10 figures, 1 appendix
Published: 2020

40. Evolution of porous dust grains in protoplanetary discs – I. Growing grains

Author: Anthony J. L. Garcia, Jean-François Gonzalez, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), ANR-11-IDEX-0007,Avenir L.S.E.,PROJET AVENIR LYON SAINT-ETIENNE(2011), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Physics, Planetesimal, 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], 01 natural sciences, Grain growth, symbols.namesake, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Planet, Stokes' law, 0103 physical sciences, symbols, Astrophysics::Earth and Planetary Astrophysics, Porosity, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics, 0105 earth and related environmental sciences
Abstract: One of the main problems in planet formation, hampering the growth of small dust to planetesimals, is the so-called radial-drift barrier. Pebbles of cm to dm sizes are thought to drift radially across protoplanetary discs faster than they can grow to larger sizes, and thus to be lost to the star. To overcome this barrier, drift has to be slowed down or stopped, or growth needs to be sped up. In this paper, we investigate the role of porosity on both drift and growth. We have developed a model for porosity evolution during grain growth and applied it to numerical simulations of protoplanetary discs. We find that growth is faster for porous grains, enabling them to transition to the Stokes drag regime, decouple from the gas, and survive the radial-drift barrier. Direct formation of small planetesimals from porous dust is possible over large areas of the disc., MNRAS 493, 1788 (2020). 13 pages, 13 figures. Correction of a typo in the algorithm of Appendix A4
Published: 2020

41. The Giant Radio Array for Neutrino Detection (GRAND): Science and design

Author: GRAND Collaboration, Alvarez-Muniz, Jaime, Batista, Rafael Alves, V., Aswathi Balagopal, Bolmont, Julien, Bustamante, Mauricio, Carvalho, Washington R., Charrier, Didier, Cognard, Ismael, Decoene, Valentin, Denton, Peter B., De Jong, Sijbrand J., De Vries, Krijn D., Engel, Ralph, Fang, Ke, Finley, Chad, Gabici, Stefano, Gou, QuanBu, Gu, Junhua, Guépin, Claire, Hu, Hongbo, Huang, Yan, Kotera, Kumiko, Coz, Sandra Le, Lenain, Jean-Philippe, Lu, Guo-Liang, Martineau-Huynh, Olivier, Mostafá, Miguel, Mottez, Fabrice, Murase, Kohta, Niess, Valentin, Oikonomou, Foteini, Pierog, Tanguy, Qian, Xiangli, Qin, Bo, Ran, Duan, Renault-Tinacci, Nicolas, Roth, Markus, Schröder, Frank G., Schüssler, Fabian, Tasse, Cyril, Timmermans, Charles, Tueros, Matias, Wu, Xiangping, Zarka, Philippe, Zech, Andreas, Zhang, B. Theodore, Zhang, Jianli, Zhang, Yi, Zheng, Qian, Zilles, Anne, Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE (UMR_7585)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique subatomique et des technologies associées (SUBATECH), Université de Nantes - Faculté des Sciences et des Techniques, Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), 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), AstroParticule et Cosmologie (APC (UMR_7164)), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Galaxies, Etoiles, Physique, Instrumentation (GEPI), PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Saarland University [Saarbrücken], Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-IMT Atlantique Bretagne-Pays de la Loire (IMT Atlantique), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-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 d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Nantes (UN)-Université de Nantes (UN)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), 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)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), ANR-16-CE31-0001,APACHE,Astroparticules et pulsars : connexions de basse à ultra-haute énergies(2016), Physics, and Elementary Particle Physics
Subjects: HIGH-ENERGY NEUTRINOS, cosmic radiatio, General Physics and Astronomy, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), Observatory, modular, 010303 astronomy & astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, COSMIC cancer database, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Gamma ray, Astrophysics::Instrumentation and Methods for Astrophysics, COSMIC-RAYS, neutrino: UHE, BURST, observatory, High Energy Physics - Phenomenology, galactic and extragalactic, Neutrino detector, radio wave: det, Neutrino, Astrophysics - High Energy Astrophysical Phenomena, radio telescopes, performance, air, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], PAIR PRODUCTION, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Cosmic ray, galactic and extragalactic [cosmic rays], EXTENSIVE AIR-SHOWERS, LIMIT, 0103 physical sciences, High Energy Physics, sources [radiowave radiation], 010306 general physics, SPECTRUM, neutrinos in astronomical observations, Astronomy, sensitivity, Construction plan, showers: atmosp, SIMULATIONS, PULSES, cosmic rays in astronomical observations, gamma ray, EMISSION
Abstract: The Giant Radio Array for Neutrino Detection (GRAND) is a planned large-scale observatory of ultra-high-energy (UHE) cosmic particles, with energies exceeding 10^8 GeV. Its goal is to solve the long-standing mystery of the origin of UHE cosmic rays. To do this, GRAND will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched sensitivity. GRAND will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the atmosphere. Its design is modular: 20 separate, independent sub-arrays, each of 10 000 radio antennas deployed over 10 000 km^2. A staged construction plan will validate key detection techniques while achieving important science goals early. Here we present the science goals, detection strategy, preliminary design, performance goals, and construction plans for GRAND., 45 pages, 34 figures. Matches published version
Published: 2020

42. Self-induced dust traps around snow lines in protoplanetary discs

Author: Arnaud Vericel, Jean-François Gonzalez, 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), ANR-16-CE31-0013,PLANET-FORMING-DISKS,De meilleurs modèles pour de meilleures données(2016), ANR-10-LABX-0066,LIO,Lyon Institute of Origins(2010), and ANR-11-IDEX-0007,Avenir L.S.E.,PROJET AVENIR LYON SAINT-ETIENNE(2011)
Subjects: [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Dust particles, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, methods: numerical, Physics::Geophysics, Astrobiology, Planet, 0103 physical sciences, Snow line, planets and satellites: formation, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Earth and Planetary Astrophysics (astro-ph.EP), Physics, 010308 nuclear & particles physics, Astronomy and Astrophysics, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Snow, protoplanetary discs, 13. Climate action, Space and Planetary Science, Protoplanetary disc, hydrodynamics, Sublimation (phase transition), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: Dust particles need to grow efficiently from micrometre sizes to thousands of kilometres to form planets. With the growth of millimetre to meter sizes being hindered by a number of barriers, the recent discovery that dust evolution is able to create `self-induced' dust traps shows promises. The condensation and sublimation of volatile species at certain locations, called snow lines, is also thought to be an important part of planet formation scenarios. Given that dust sticking properties change across a snow line, this raises the question: how do snow lines affect the self-induced dust trap formation mechanism? The question is particularly relevant with the multiple observations of the carbon monoxide (CO) snow line in protoplanetary discs, since its effect on dust growth and dynamics is yet to be understood. In this paper, we present the effects of snow lines in general on the formation of self-induced dust traps in a parameter study, then focus on the CO snow line. We find that for a range of parameters, a dust trap forms at the snow line where the dust accumulates and slowly grows, as found for the water snow line in previous work. We also find that, depending on the grains sticking properties on either side of the CO snow line, it could either be a starting or braking point for dust growth and drift. This could provide clues to understand the link between dust distributions and snow lines in protoplanetary disc observations., Comment: 14 pages, 14 figures
Published: 2019

43. Exploring deep, hot, adiabats as a potential solution to the radius inflation problem in Brown dwarfs

Author: Sarah L. Casewell, M. W. Phillips, J. D. Lothringer, F. Sainsbury-Martinez, Pascal Tremblin, Maison de la Simulation (MDLS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut National de Recherche en Informatique et en Automatique (Inria)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Johns Hopkins University (JHU), Institute for Geophysics, University of Texas, University of Texas at Austin [Austin], University of Leicester, School of Physics and Astronomy [Exeter], University of Exeter, European Project: 757858,ATMO, The authors also wish to thank Idris, CNRS, and MDLS for access to the supercomputer Poincare, without which the long-timescale calculations featured in this work would not have been possible., Additionally this work was granted access to the HPC resources of IDRIS (Jean-Zay) and CEA-TGCC (Irene/Joliot-Curie) under the 2020/2021 allocation – A0080410870 made as part of the GENCI Dari A8 call., and European Research Council
Subjects: 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Brown dwarf, FOS: Physical sciences, Astrophysics, 01 natural sciences, Kepler, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, planets and satellites: fundamental parameters, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Inflation (cosmology), planets and satellites: atmospheres, Astronomy and Astrophysics, Radius, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], planets and satellites: interiors, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - Earth and Planetary Astrophysics, brown dwarfs
Abstract: The anomalously large radii of highly-irradiated gaseous exoplanets has long been a mystery. One mechanism suggested as a solution for hot Jupiters is the heating of the deep atmosphere via the vertical advection of potential temperature resulting in an increased internal entropy. Here we intend to explore if this mechanism can also explain the observed brown dwarf radii trend: a general increase in radius with irradiation, with an exception for highly-irradiated brown dwarfs orbiting white dwarfs. We use a 3D GCM, DYNAMICO, to run a series of long-timescale models of the atmospheres of Kepler-13Ab, KELT-1b, and SDSS1411B. These models allow us to explore not only if a stable advective adiabat can develop, but also the associated dynamics. We find that our models fall into two distinct regimes: Kepler-13Ab and KELT-1b both show signs of significant deep heating and hence maintain adiabats that are hotter than 1D models predict. On the other hand, SDSS1411B exhibits a much weaker downward heating profile which not only struggles to heat the interior under ideal conditions, but is highly sensitive to the presence of deep radiative dynamics. We find that the vertical advection of potential temperature by large-scale atmospheric circulations represents a robust mechanism to explain the trend of increasing inflation with irradiation, including the exception for highly irradiated brown dwarfs orbiting white dwarfs. This can be understood as occurring due to the role that increasing rotational influence plays on mid- to-high latitude advective dynamics. Furthermore, when paired with a suitable parametrisation of the outer atmosphere irradiation profile, this mechanism alone could potentially provide a complete explanation for the observed levels of inflation in our brown dwarfs., 20 pages, 11 figures. Accepted for publication in A&A. Updated version with a fixed typo in the vertical enthalpy flux equation
Published: 2021

44. Massive multi-mission statistical study and analytical modeling of the Earth's magnetopause: 1 - A gradient boosting based automatic detection of near-Earth regions

Author: Benoit Lavraud, Bayane Michotte de Welle, Dominique Fontaine, N. Aunai, Gautier Nguyen, Alexis Jeandet, and Direction générale de l'Armement (DGA)
Subjects: Spacecraft, business.industry, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Astrophysics::High Energy Astrophysical Phenomena, Magnetosphere, Geophysics, 7. Clean energy, Solar wind, Magnetosheath, 13. Climate action, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], Physics::Space Physics, Astrophysics::Solar and Stellar Astrophysics, Classification methods, Magnetopause, Astrophysics::Earth and Planetary Astrophysics, Gradient boosting, business, Earth (classical element), Geology
Abstract: We present an automatic classification method of the three near-Earth regions, the magnetosphere, the magnetosheath and the solar wind from their in-situ data measurement by multiple spacecraft. Ba...
Published: 2021

45. Interplanetary transfers using stable and unstable manifold tubes originating at L1 and L2 in the elliptic restricted three-body problems

Author: Scantamburlo, E., Guzzo, M., Paez, R. I., Dipartimento di Matematica 'Tullio Levi-Civita', Universita degli Studi di Padova, and MIUR-PRIN 20178CJA2AB ‘New Frontiers of Celestial Mechanics: theory and applications’
Subjects: Elliptic restricted three-body problem, Low-energy transfers, [MATH.MATH-MP]Mathematics [math]/Mathematical Physics [math-ph], [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [NLIN.NLIN-CD]Nonlinear Sciences [physics]/Chaotic Dynamics [nlin.CD], Interplanetary transfers, Astrophysics::Earth and Planetary Astrophysics, Lagrangian solutions
Abstract: The solutions originating at the Lagrangian points L 1 and L 2 of the restricted three-body problem are used in space flight dynamics to find useful station-keeping orbits as well as convenient lowenergy transfers between planets and satellites of the Solar System. The circular restricted three-body problem (CR3BP) provides the simplest model where the Lagrangian points, as well as the related stable and unstable manifold tubes, are defined. Nevertheless, their use for Solar System applications requires to consider hierarchical extensions of the model. The elliptic restricted three-body problem (ER3BP) is the most important extension to consider for space flight dynamics. In this paper we discuss the differences of the manifold tubes of the ER3BP with respect to the CR3BP which have an impact in the transfers between orbits in the manifold tubes related to different planets. We find that there is a threshold value for the eccentricity of the planet, depending on its reduced mass, which changes drastically the distribution of the longitudes of the first perycenter (or apocenter) of the orbits in the manifold tubes leaving or approaching the Lagrangian points L 1 , L 2. For example, such a difference changes the design of the Hohmann transfers between two orbits of the manifold tubes when the planets Mercury or Mars are concerned.
Published: 2021

46. Study of the Reactivity of CH3COOH+• and COOH+ Ions with CH3NH2: Evidence of the Formation of New Peptide-like C(O)−N Bonds

Author: Christian Alcaraz, Imene Derbali, R. Thissen, Emilie-Laure Zins, Claire Romanzin, Institut de Chimie Physique (ICP), and Institut de Chimie du CNRS (INC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010304 chemical physics, Formic acid, Methylamine, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 010402 general chemistry, Photochemistry, 01 natural sciences, Dissociation (chemistry), 0104 chemical sciences, [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, chemistry.chemical_compound, Acetic acid, chemistry, 0103 physical sciences, Molecule, Peptide bond, Reactivity (chemistry), [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physical and Theoretical Chemistry, Acetamide, ComputingMilieux_MISCELLANEOUS
Abstract: Acetamide, a small organic compound containing a peptide bond, was observed in the interstellar medium, but reaction pathways leading to the formation of this prebiotic molecule remain uncertain. We investigated the possible formation of a peptide-like bond from the reaction between acetic acid (CH3-COOH) and methylamine (CH3-NH2) that were identified in the interstellar medium. From an experimental point of view, a quadrupole/octopole/quadrupole mass spectrometer was used in combination with synchrotron radiation as a tunable source of VUV photons for monitoring the reactivity of selected ions. Acetic acid was photoionized, and the reactivity of CH3COOH+• as well as COOH+ (produced from either acetic acid or formic acid) ions with neutral CH3NH2 was further studied. With no surprise, charge transfer, proton transfer, and concomitant dissociation processes were found to largely dominate the reactivity. However, a C(O)-N bond formation process between the two reactants was also evidenced, with a weak cross section reaction. From a theoretical point of view, results concerning reactivity and barrier heights were obtained using density functional theory, with the LC-ωPBE range-separated functional in combination with the 6-311++G(d,p) Pople basis set and are in perfect agreement with the experimental data.
Published: 2021

47. Stratified Radiative Transfer in a Fluid *

Author: Golse, François, Pironneau, Olivier, Laboratoire Jacques-Louis Lions (LJLL), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Pironneau, Olivier
Subjects: Numerical analysis AMS3510, [PHYS.ASTR.EP] Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], 80M10, Temperature equation, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], [INFO.INFO-NA] Computer Science [cs]/Numerical Analysis [cs.NA], 35Q85, 80A21, Radiative transfer, Astrophysics::Earth and Planetary Astrophysics, [INFO.INFO-NA]Computer Science [cs]/Numerical Analysis [cs.NA], Integral equation, 35Q35
Abstract: New mathematical results are given for the Radiative Transfer equations alone and coupled with the temperature equation of a fluid: existence, uniqueness, a maximum principle and a convergent monotone iterative scheme. Numerical tests for Earth's atmosphere and the heating of a pool by the Sun are included.
Published: 2021

48. Origin and dynamical evolution of the asteroid belt

Author: Raymond, Sean N., Nesvorný, David, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Department of Space Studies [Boulder], and Southwest Research Institute [Boulder] (SwRI)
Subjects: Earth and Planetary Astrophysics (astro-ph.EP), Physics - Geophysics, Astrophysics - Solar and Stellar Astrophysics, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Physics::Space Physics, FOS: Physical sciences, Astrophysics::Earth and Planetary Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Geophysics (physics.geo-ph), Astrophysics - Earth and Planetary Astrophysics
Abstract: The asteroid belt was dynamically shaped during and after planet formation. Despite representing a broad ring of stable orbits, the belt contains less than one one-thousandth of an Earth mass. The asteroid orbits are dynamically excited with a wide range in eccentricity and inclination and their compositions are diverse, with a general trend toward dry objects in the inner belt and more water-rich objects in the outer belt. Here we review models of the asteroid belt's origins and dynamical history. The classical view is that the belt was born with several Earth masses in planetesimals, then strongly depleted. However, it is possible that very few planetesimals ever formed in the asteroid region and that the belt's story is one of implantation rather than depletion. A number of processes may have implanted asteroids from different regions of the Solar System, dynamically removed them, and excited their orbits. During the gaseous disk phase these include the effects of giant planet growth and migration and sweeping secular resonances. After the gaseous disk phase these include scattering from resident planetary embryos, chaos in the giant planets' orbits, the giant planet instability, and long-term dynamical evolution. Different global models for Solar System formation imply contrasting dynamical histories of the asteroid belt. Vesta and Ceres may have been implanted from opposite regions of the Solar System -- Ceres from the Jupiter-Saturn region and Vesta from the terrestrial planet region -- and could therefore represent very different formation conditions., Chapter to appear in Vesta and Ceres: Insights into the Dawn of the Solar System (Cambridge U. Press; Editors Simone Marchi, Carol A. Raymond, and Christopher T. Russell). Updated figures
Published: 2021

49. Stable stratification promotes multiple zonal jets in a turbulent jovian dynamo model

Author: Johannes Wicht, Thomas Gastine, Institut de Physique du Globe de Paris (IPGP), Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Max Planck Institute for Solar System Research (MPS), and Max-Planck-Gesellschaft
Subjects: Buoyancy, 010504 meteorology & atmospheric sciences, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], FOS: Physical sciences, engineering.material, Kinetic energy, 01 natural sciences, Jovian, Physics - Geophysics, Jupiter, 0103 physical sciences, 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Magnetic energy, Fluid Dynamics (physics.flu-dyn), Astronomy and Astrophysics, Physics - Fluid Dynamics, Mechanics, Magnetic flux, Geophysics (physics.geo-ph), Magnetic field, 13. Climate action, Space and Planetary Science, Physics::Space Physics, engineering, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics, Dynamo
Abstract: The ongoing NASA's Juno mission puts new constraints on the internal dynamics of Jupiter. Data gathered by its onboard magnetometer reveal a dipole-dominated surface magnetic field accompanied by strong localised magnetic flux patches. The gravity measurements indicate that the fierce surface zonal jets extend several thousands of kilometers below the cloud level before rapidly decaying below $0.94-0.96\,R_J$, $R_J$ being the mean Jovian radius at the one bar level. Several internal models suggest an intricate internal structure with a thin intermediate region in which helium would segregate from hydrogen, forming a compositionally-stratified layer. Here, we develop the first global Jovian dynamo which incorporates an intermediate stably-stratified layer between $0.82\,R_J$ and $0.86\,R_J$. Analysing the energy balance reveals that the magnetic energy is almost one order of magnitude larger than kinetic energy in the metallic region, while most of the kinetic energy is pumped into zonal motions in the molecular envelope. Those result from the different underlying force hierarchy with a triple balance between Lorentz, Archimedean and ageostrophic Coriolis forces in the metallic core and inertia, buoyancy and ageostrophic Coriolis forces controlling the external layers. The simulation presented here is the first to demonstrate that multiple zonal jets and dipole-dominated dynamo action can be consolidated in a global simulation. The inclusion of an stable layer is a necessary ingredient that allows zonal jets to develop in the outer envelope without contributing to the dynamo action in the deeper metallic region. Stable stratification however also smooths out the small-scale features of the magnetic field by skin effect. These constraints suggest that possible stable layers in Jupiter should be located much closer to the surface ($0.9-0.95\,R_J$)., 23 pages, 16 figures, 2 tables, accepted for publication in Icarus
Published: 2021

50. OSSOS finds an exponential cutoff in the size distribution of the cold classical Kuiper Belt

Author: Michele T. Bannister, Stephen Gwyn, Ying-Tung Chen, Volk Kathryn, Jean-Marc Petit, Mike Alexandersen, J. J. Kavelaars, Brett Gladman, Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Université de Franche-Comté (UFC), and Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)
Subjects: Solar System, Planetesimal, [PHYS.ASTR.EP]Physics [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Population, 0211 other engineering and technologies, FOS: Physical sciences, 02 engineering and technology, Astrophysics, classical Kuiper belt objects, Protoplanetary disk, 01 natural sciences, Kuiper belt, 0103 physical sciences, trans-Neptunian objects, Trans-Neptunian object, education, 010303 astronomy & astrophysics, Minor planet, 021101 geological & geomatics engineering, Physics, Earth and Planetary Astrophysics (astro-ph.EP), education.field_of_study, Astronomy and Astrophysics, Accretion (astrophysics), 13. Climate action, Space and Planetary Science, Streaming instability, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract: The cold main classical Kuiper Belt consists of those non-resonant small solar system bodies with low orbital inclinations and orbital semi-major axes between 42.4 and 47.7 au. These objects likely formed \textit{in situ} and the population has experienced minimal collisional modification since formation. Using the Outer Solar System Origins Survey (OSSOS) ensemble sample and characterization, combined with constraints from deeper surveys and supported by evidence from the Minor Planet Center catalog and the Deep Ecliptic Survey, we determine the absolute magnitude $H_r$ distribution of the cold classical belt from $H_r\simeq5$ to 12 (roughly diameters of 400 km to 20 km). We conclude that the cold population's $H_r$ distribution exhibits an exponential cutoff at large sizes. Exponential cutoffs at large sizes are not a natural outcome of pair-wise particle accretion but exponentially tapered power-law size distributions are a feature of numerical simulations of planetesimal formation via a streaming instability. Our observation of an exponential cutoff agrees with previous observational inferences that no large objects ($D \gtrsim 400$ km) exist in the cold population. We note that the asymptotic slope of the $H_r$ distribution is consistent with $\alpha \sim 0.4$ and this asymptotic slope is also found in streaming instability modelling of planetesimal formation and is thus not necessarily associated with achieving collisional equilibrium. Studies of the transneptunian region are providing the parameters that will enable future streaming-instability studies to determine the initial conditions of planetesimal formation in the $\approx$45 au region of the Sun's protoplanetary disk., Comment: 20 pages, 2 figures, accepted in AAS Journals
Published: 2021

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