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10 results on '"Girard, JH"'

1. Large Interferometer For Exoplanets (LIFE)

Author

Quanz, SP, Ottiger, M, Fontanet, E, Kammerer, J, Menti, F, Dannert, F, Gheorghe, A, Absil, O, Airapetian, VS, Alei, E, Allart, R, Angerhausen, D, Blumenthal, S, Buchhave, LA, Cabrera, J, Carrión-González, Ó, Chauvin, G, Danchi, WC, Dandumont, C, Defrére, D, Dorn, C, Ehrenreich, D, Ertel, S, Fridlund, M, Muñoz, A García, Gascón, C, Girard, JH, Glauser, A, Grenfell, JL, Guidi, G, Hagelberg, J, Helled, R, Ireland, MJ, Janson, M, Kopparapu, RK, Korth, J, Kozakis, T, Kraus, S, Léger, A, Leedjärv, L, Lichtenberg, T, Lillo-Box, J, Linz, H, Liseau, R, Loicq, J, Mahendra, V, Malbet, F, Mathew, J, Mennesson, B, Meyer, MR, Mishra, L, Molaverdikhani, K, Noack, L, Oza, AV, Pallé, E, Parviainen, H, Quirrenbach, A, Rauer, H, Ribas, I, Rice, M, Romagnolo, A, Rugheimer, S, Schwieterman, EW, Serabyn, E, Sharma, S, Stassun, KG, Szulágyi, J, Wang, HS, Wunderlich, F, and Wyatt, MC

Subjects
planets and satellites, terrestrial planets, telescopes, instrumentation, high angular resolution, methods, numerical, detection, infrared, planetary systems, Astronomical and Space Sciences, Astronomy & Astrophysics
Abstract

Context. One of the long-term goals of exoplanet science is the atmospheric characterization of dozens of small exoplanets in order to understand their diversity and search for habitable worlds and potential biosignatures. Achieving this goal requires a space mission of sufficient scale that can spatially separate the signals from exoplanets and their host stars and thus directly scrutinize the exoplanets and their atmospheres.Aims. We seek to quantify the exoplanet detection performance of a space-based mid-infrared (MIR) nulling interferometer that measures the thermal emission of exoplanets. We study the impact of various parameters and compare the performance with that of large single-aperture mission concepts that detect exoplanets in reflected light.Methods. We have developed an instrument simulator that considers all major astrophysical noise sources and coupled it with Monte Carlo simulations of a synthetic exoplanet population around main-sequence stars within 20 pc of the Sun. This allows us to quantify the number (and types) of exoplanets that our mission concept could detect. Considering single visits only, we discuss two different scenarios for distributing 2.5 yr of an initial search phase among the stellar targets. Different apertures sizes and wavelength ranges are investigated.Results. An interferometer consisting of four 2 m apertures working in the 4–18.5 μ.m wavelength range with a total instrument throughput of 5% could detect up to ≈550 exoplanets with radii between 0.5 and 6 R⊕ with an integrated S/N ≥ 7. At least ≈160 of the detected exoplanets have radii ≤1.5 R⊕. Depending on the observing scenario, ≈25–45 rocky exoplanets (objects with radii between 0.5 and 1.5 R⊕) orbiting within the empirical habitable zone (eHZ) of their host stars are among the detections. With four 3.5 m apertures, the total number of detections can increase to up to ≈770, including ≈60–80 rocky eHZ planets. With four times 1 m apertures, the maximum detection yield is ≈315 exoplanets, including ≤20 rocky eHZ planets. The vast majority of small, temperate exoplanets are detected around M dwarfs. The impact of changing the wavelength range to 3–20 μm or 6–17 μm on the detection yield is negligible.Conclusions. A large space-based MIR nulling interferometer will be able to directly detect hundreds of small, nearby exoplanets, tens of which would be habitable world candidates. This shows that such a mission can compete with large single-aperture reflected light missions. Further increasing the number of habitable world candidates, in particular around solar-type stars, appears possible via the implementation of a multi-visit strategy during the search phase. The high median S/N of most of the detected planets will allow for first estimates of their radii and effective temperatures and will help prioritize the targets for a second mission phase to obtain high-S/N thermal emission spectra, leveraging the superior diagnostic power of the MIR regime compared to shorter wavelengths.

Published
2022

2. Physical, spectral, and dynamical properties of asteroid (107) Camilla and its satellites

Author

Pajuelo, M, Carry, B, Vachier, F, Marsset, M, Berthier, J, Descamps, P, Merline, WJ, Tamblyn, PM, Grice, J, Conrad, A, Storrs, A, Timerson, B, Dunham, D, Preston, S, Vigan, A, Yang, B, Vernazza, P, Fauvaud, S, Bernasconi, L, Romeuf, D, Behrend, R, Dumas, C, Drummond, JD, Margot, J-L, Kervella, P, Marchis, F, and Girard, JH

Subjects
Space Sciences, Physical Sciences, Asteroids, Composition, Satellites of asteroids, Photometry, Spectroscopy, astro-ph.EP, Astronomical and Space Sciences, Geochemistry, Geophysics, Astronomy & Astrophysics, Astronomical sciences, Space sciences
Abstract

The population of large asteroids is thought to be primordial and they arethe most direct witnesses of the early history of our Solar System. Thosesatellites allow study of the mass, and hence density and internal structure.We study here the properties of the triple asteroid (107) Camilla fromlightcurves, stellar occultations, optical spectroscopy, and high-contrast andhigh-angular-resolution images and spectro-images. Using 80 positions over 15years, we determine the orbit of its larger satellite to be circular,equatorial, and prograde, with RMS residuals of 7.8 mas. From 11 positions inthree epochs only, in 2015 and 2016, we determine a preliminary orbit for thesecond satellite. We find the orbit to be somewhat eccentric and slightlyinclined to the primary's equatorial plane, reminiscent of the inner satellitesof other asteroid triple systems. Comparison of the near-infrared spectrum ofthe larger satellite reveals no significant difference with Camilla. Hence,these properties argue for a formation of the satellites by excavation fromimpact and re-accumulation of ejecta. We determine the spin and 3-D shape ofCamilla. The model fits well each data set. We determine Camilla to be largerthan reported from modeling of mid-infrared photometry, with aspherical-volume-equivalent diameter of 254 $\pm$ 36 km (3 $\sigma$uncertainty), in agreement with recent results from shape modeling(Hanus2017+). Combining the mass of (1.12 $\pm$ 0.01) $\times$ 10$^{19}$ kgdetermined from the dynamics of the satellites and the volume from the 3-Dshape model, we determine a density of 1,280 $\pm$ 130 SI. From this density,and considering Camilla's spectral similarities with (24) Themis and (65)Cybele (for which water ice coating on surface grains was reported), we infer asilicate-to-ice mass ratio of 1-6, with a 10-30% macroporosity.

Published
2018

3. Ground-based transit observations of the super-Earth GJ 1214 b⋆⋆⋆

Author

Cáceres, C, Kabath, P, Hoyer, S, Ivanov, VD, Rojo, P, Girard, JH, Kempton, E Miller-Ricci, Fortney, JJ, and Minniti, D

Subjects
planetary systems, techniques: photometric, techniques: spectroscopic, planets and satellites: atmospheres, stars: individual: GJ 1214, astro-ph.EP, astro-ph.SR, Astronomical and Space Sciences, Astronomy & Astrophysics
Abstract

Context. GJ 1214 b is one of the few known transiting super-Earth-sized exoplanets with a measured mass and radius. It orbits an M-dwarf, only 14.55? pc away, making it a favorable candidate for follow-up studies. However, the composition of GJ? 1214? b's mysterious atmosphere has yet to be fully unveiled. Aims. Our goal is to distinguish between the various proposed atmospheric models to explain the properties of GJ? 1214? b: hydrogen-rich or hydrogen-He mix, or a heavy molecular weight atmosphere with reflecting high clouds, as latest studies have suggested. Methods. Wavelength-dependent planetary radii measurements from the transit depths in the optical/NIR are the best tool to investigate the atmosphere of GJ? 1214? b. We present here (i) photometric transit observations with a narrow-band filter centered on 2.14? μm and a broad-band I-Bessel filter centered on 0.8665? μm, and (ii) transmission spectroscopy in the H and K atmospheric windows that cover three transits. The photometric and spectrophotometric time series obtained were analyzed with MCMC simulations to measure the planetary radii as a function of wavelength. We determined radii ratios of 0.1173-0.0024+0.0022 for I-Bessel and 0.11735-0.00076+0.00072 at 2.14? μm. Results. Our measurements indicate a flat transmission spectrum, in agreement with the last atmospheric models that favor featureless spectra with clouds and high molecular weight compositions. © ESO, 2014.

Published
2014

4. The JWST Early-release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 μm Spectrum of the Planetary-mass Companion VHS 1256-1257 b

Author

Miles, BE, Biller, BA, Patapis, P, Worthen, K, Rickman, E, Hoch, KKW, Skemer, A, Perrin, MD, Whiteford, N, Chen, CH, Sargent, B, Mukherjee, S, Morley, CV, Moran, SE, Bonnefoy, M, Petrus, S, Carter, AL, Choquet, E, Hinkley, S, Ward-Duong, K, Leisenring, JM, Millar-Blanchaer, MA, Pueyo, L, Ray, S, Sallum, S, Stapelfeldt, KR, Stone, JM, Wang, JJ, Absil, O, Balmer, WO, Boccaletti, A, Bonavita, M, Booth, M, Bowler, BP, Chauvin, G, Christiaens, V, Currie, T, Danielski, C, Fortney, JJ, Girard, JH, Grady, CA, Greenbaum, AZ, Henning, T, Hines, DC, Janson, M, Kalas, P, Kammerer, J, Kennedy, GM, Kenworthy, MA, Kervella, P, Lagage, PO, Lew, BWP, Liu, MC, Macintosh, B, Marino, S, Marley, MS, Marois, C, Matthews, EC, Matthews, BC, Mawet, D, McElwain, MW, Metchev, S, Meyer, MR, Molliere, P, Pantin, E, Quirrenbach, A, Rebollido, I, Ren, BB, Schneider, G, Vasist, M, Wyatt, MC, Zhou, Y, Briesemeister, ZW, Bryan, ML, Calissendorff, P, Cantalloube, F, Cugno, G, De Furio, M, Dupuy, TJ, Factor, SM, Faherty, JK, Fitzgerald, MP, Franson, K, Gonzales, EC, Hood, CE, Howe, AR, Kraus, AL, Kuzuhara, M, Lagrange, AM, Lawson, K, Lazzoni, C, Liu, P, Llop-Sayson, J, Lloyd, JP, Martinez, RA, Mazoyer, J, Quanz, SP, Redai, JA, Samland, M, Schlieder, JE, Miles, BE [0000-0002-5500-4602], Biller, BA [0000-0003-4614-7035], Patapis, P [0000-0001-8718-3732], Worthen, K [0000-0002-5885-5779], Rickman, E [0000-0003-4203-9715], Hoch, KKW [0000-0002-9803-8255], Skemer, A [0000-0001-6098-3924], Perrin, MD [0000-0002-3191-8151], Whiteford, N [0000-0001-8818-1544], Chen, CH [0000-0002-8382-0447], Sargent, B [0000-0001-9855-8261], Mukherjee, S [0000-0003-1622-1302], Morley, CV [0000-0002-4404-0456], Moran, SE [0000-0002-6721-3284], Bonnefoy, M [0000-0001-5579-5339], Petrus, S [0000-0003-0331-3654], Carter, AL [0000-0001-5365-4815], Choquet, E [0000-0002-9173-0740], Hinkley, S [0000-0001-8074-2562], Ward-Duong, K [0000-0002-4479-8291], Leisenring, JM [0000-0002-0834-6140], Millar-Blanchaer, MA [0000-0001-6205-9233], Ray, S [0000-0003-2259-3911], Sallum, S [0000-0001-6871-6775], Stapelfeldt, KR [0000-0002-2805-7338], Stone, JM [0000-0003-0454-3718], Wang, JJ [0000-0003-0774-6502], Absil, O [0000-0002-4006-6237], Balmer, WO [0000-0001-6396-8439], Boccaletti, A [0000-0001-9353-2724], Bonavita, M [0000-0002-7520-8389], Booth, M [0000-0001-8568-6336], Bowler, BP [0000-0003-2649-2288], Chauvin, G [0000-0003-4022-8598], Christiaens, V [0000-0002-0101-8814], Currie, T [0000-0002-7405-3119], Danielski, C [0000-0002-3729-2663], Fortney, JJ [0000-0002-9843-4354], Girard, JH [0000-0001-8627-0404], Greenbaum, AZ [0000-0002-7162-8036], Henning, T [0000-0002-1493-300X], Hines, DC [0000-0003-4653-6161], Janson, M [0000-0001-8345-593X], Kalas, P [0000-0002-6221-5360], Kammerer, J [0000-0003-2769-0438], Kennedy, GM [0000-0001-6831-7547], Kenworthy, MA [0000-0002-7064-8270], Kervella, P [0000-0003-0626-1749], Lew, BWP [0000-0003-1487-6452], Liu, MC [0000-0003-2232-7664], Macintosh, B [0000-0003-1212-7538], Marino, S [0000-0002-5352-2924], Marley, MS [0000-0002-5251-2943], Marois, C [0000-0002-4164-4182], Matthews, EC [0000-0003-0593-1560], Matthews, BC [0000-0003-3017-9577], Mawet, D [0000-0002-8895-4735], McElwain, MW [0000-0003-0241-8956], Metchev, S [0000-0003-3050-8203], Meyer, MR [0000-0003-1227-3084], Molliere, P [0000-0003-4096-7067], Pantin, E [0000-0001-6472-2844], Rebollido, I [0000-0002-4388-6417], Ren, BB [0000-0003-1698-9696], Schneider, G [0000-0002-4511-5966], Vasist, M [0000-0002-4511-3602], Wyatt, MC [0000-0001-9064-5598], Zhou, Y [0000-0003-2969-6040], Briesemeister, ZW [0000-0002-1764-2494], Bryan, ML [0000-0002-6076-5967], Calissendorff, P [0000-0002-5335-0616], Cantalloube, F [0000-0002-3968-3780], Cugno, G [0000-0001-7255-3251], De Furio, M [0000-0003-1863-4960], Dupuy, TJ [0000-0001-9823-1445], Factor, SM [0000-0002-8332-8516], Faherty, JK [0000-0001-6251-0573], Fitzgerald, MP [0000-0002-0176-8973], Franson, K [0000-0003-4557-414X], Gonzales, EC [0000-0003-4636-6676], Hood, CE [0000-0003-1150-7889], Howe, AR [0000-0002-4884-7150], Kraus, AL [0000-0001-9811-568X], Kuzuhara, M [0000-0002-4677-9182], Lawson, K [0000-0002-6964-8732], Lazzoni, C [0000-0001-7819-9003], Liu, P [0000-0001-7047-0874], Llop-Sayson, J [0000-0002-3414-784X], Martinez, RA [0000-0001-6301-896X], Mazoyer, J [0000-0002-9133-3091], Quanz, SP [0000-0003-3829-7412], Redai, JA [0000-0002-4489-3168], Samland, M [0000-0001-9992-4067], Schlieder, JE [0000-0001-5347-7062], and Apollo - University of Cambridge Repository

Subjects
The Solar System, Exoplanets, and Astrobiology, 5109 Space Sciences, 51 Physical Sciences
Abstract

We present the highest fidelity spectrum to date of a planetary-mass object. VHS 1256 b is a M Jup widely separated (∼8″, a = 150 au), young, planetary-mass companion that shares photometric colors and spectroscopic features with the directly imaged exoplanets HR 8799c, d, and e. As an L-to-T transition object, VHS 1256 b exists along the region of the color–magnitude diagram where substellar atmospheres transition from cloudy to clear. We observed VHS 1256 b with JWST's NIRSpec IFU and MIRI MRS modes for coverage from 1 to 20 μm at resolutions of ∼1000–3700. Water, methane, carbon monoxide, carbon dioxide, sodium, and potassium are observed in several portions of the JWST spectrum based on comparisons from template brown dwarf spectra, molecular opacities, and atmospheric models. The spectral shape of VHS 1256 b is influenced by disequilibrium chemistry and clouds. We directly detect silicate clouds, the first such detection reported for a planetary-mass companion.

Published
2023

5. Discovery of a low-mass companion inside the debris ring surrounding the F5V star HD 206893

Author

Milli, J, Hibon, P, Christiaens, V, Choquet, Bonnefoy, M, Kennedy, GM, Wyatt, MC, Absil, O, González, CAG, Del Burgo, C, Matrà, L, Augereau, JC, Boccaletti, A, Delacroix, C, Ertel, S, Dent, WRF, Forsberg, P, Fusco, T, Girard, JH, Habraken, S, Huby, E, Karlsson, M, Lagrange, AM, Mawet, D, Mouillet, D, Perrin, M, Pinte, C, Pueyo, L, Reyes, C, Soummer, R, Surdej, J, Tarricq, Y, and Wahhaj, Z

Subjects
planet-disk interactions, 13. Climate action, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, circumstellar matter, planetary systems, Astrophysics::Galaxy Astrophysics, brown dwarfs
Abstract

Aims. Uncovering the ingredients and the architecture of planetary systems is a very active field of research that has fuelled many new theories on giant planet formation, migration, composition, and interaction with the circumstellar environment. We aim at discovering and studying new such systems, to further expand our knowledge of how low-mass companions form and evolve. Methods. We obtained high-contrast H-band images of the circumstellar environment of the F5V star HD 206893, known to host a debris disc never detected in scattered light. These observations are part of the SPHERE High Angular Resolution Debris Disc Survey (SHARDDS) using the InfraRed Dual-band Imager and Spectrograph (IRDIS) installed on VLT/SPHERE. Results. We report the detection of a source with a contrast of 3.6 × 10-5 in the H-band, orbiting at a projected separation of 270 milliarcsec or 10 au, corresponding to a mass in the range 24 to 73 MJup for an age of the system in the range 0.2 to 2 Gyr. The detection was confirmed ten months later with VLT/NaCo, ruling out a background object with no proper motion. A faint extended emission compatible with the disc scattered light signal is also observed. Conclusions. The detection of a low-mass companion inside a massive debris disc makes this system an analog of other young planetary systems such as β Pictoris, HR 8799 or HD 95086 and requires now further characterisation of both components to understand their interactions.

6. First Scattered-light Images of the Gas-rich Debris Disk around 49 Ceti

Author

Choquet, E, Milli, J, Wahhaj, Z, Soummer, R, Roberge, A, Augereau, JC, Booth, M, Absil, O, Boccaletti, A, Chen, CH, Debes, JH, Burgo, CD, Dent, WRF, Ertel, S, Girard, JH, Gofas-Salas, E, Golimowski, DA, González, CAG, Hagan, JB, Hibon, P, Hines, DC, Kennedy, GM, Lagrange, AM, Matrà, L, Mawet, D, Mouillet, D, N'Diaye, M, Perrin, MD, Pinte, C, Pueyo, L, Rajan, A, Schneider, G, Wolff, S, and Wyatt, M

Subjects
13. Climate action, techniques: image processing, stars: individual (49 Ceti), circumstellar matter
Abstract

We present the first scattered-light images of the debris disk around 49 Ceti, a ∼40 Myr A1 main-sequence star at 59 pc, famous for hosting two massive dust belts as well as large quantities of atomic and molecular gas. The outer disk is revealed in reprocessed archival Hubble Space Telescope NICMOS-F110W images, as well as new coronagraphic H-band images from the Very Large Telescope SPHERE instrument. The disk extends from 1.″1 (65 au) to 4.″6 (250 au) and is seen at an inclination of 73°, which refines previous measurements at lower angular resolution. We also report no companion detection larger than 3 M Jup at projected separations beyond 20 au from the star (0.″34). Comparison between the F110W and H-band images is consistent with a gray color of 49 Ceti's dust, indicating grains larger than 2 μm. Our photometric measurements indicate a scattering efficiency/infrared excess ratio of 0.2-0.4, relatively low compared to other characterized debris disks. We find that 49 Ceti presents morphological and scattering properties very similar to the gas-rich HD 131835 system. From our constraint on the disk inclination we find that the atomic gas previously detected in absorption must extend to the inner disk, and that the latter must be depleted of CO gas. Building on previous studies, we propose a schematic view of the system describing the dust and gas structure around 49 Ceti and hypothetical scenarios for the gas nature and origin.

7. The JWST early release science program for the direct imaging and spectroscopy of exoplanetary systems

Author

Sasha Hinkley, Aarynn L. Carter, Shrishmoy Ray, Andrew Skemer, Beth Biller, Elodie Choquet, Maxwell A. Millar-Blanchaer, Stephanie Sallum, Brittany Miles, Niall Whiteford, Polychronis Patapis, Marshall Perrin, Laurent Pueyo, Glenn Schneider, Karl Stapelfeldt, Jason Wang, Kimberly Ward-Duong, Brendan P. Bowler, Anthony Boccaletti, Julien H. Girard, Dean Hines, Paul Kalas, Jens Kammerer, Pierre Kervella, Jarron Leisenring, Eric Pantin, Yifan Zhou, Michael Meyer, Michael C. Liu, Mickael Bonnefoy, Thayne Currie, Michael McElwain, Stanimir Metchev, Mark Wyatt, Olivier Absil, Jea Adams, Travis Barman, Isabelle Baraffe, Mariangela Bonavita, Mark Booth, Marta Bryan, Gael Chauvin, Christine Chen, Camilla Danielski, Matthew De Furio, Samuel M. Factor, Michael P. Fitzgerald, Jonathan J. Fortney, Carol Grady, Alexandra Greenbaum, Thomas Henning, Kielan K. W. Hoch, Markus Janson, Grant Kennedy, Matthew Kenworthy, Adam Kraus, Masayuki Kuzuhara, Pierre-Olivier Lagage, Anne-Marie Lagrange, Ralf Launhardt, Cecilia Lazzoni, James Lloyd, Sebastian Marino, Mark Marley, Raquel Martinez, Christian Marois, Brenda Matthews, Elisabeth C. Matthews, Dimitri Mawet, Johan Mazoyer, Mark Phillips, Simon Petrus, Sascha P. Quanz, Andreas Quirrenbach, Julien Rameau, Isabel Rebollido, Emily Rickman, Matthias Samland, B. Sargent, Joshua E. Schlieder, Anand Sivaramakrishnan, Jordan M. Stone, Motohide Tamura, Pascal Tremblin, Taichi Uyama, Malavika Vasist, Arthur Vigan, Kevin Wagner, Marie Ygouf, University of Exeter, University of California (UC), SUPA School of Physics and Astronomy [Edinburgh], University of Edinburgh, 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), California Institute of Technology (CALTECH), Institute for Astronomy [Edinburgh] (IfA), Centre for Exoplanet Science, 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), Space Telescope Science Institute (STSci), Steward Observatory, University of Arizona, University of Notre Dame [Indiana] (UND), McDonald Observatory, University of Texas at Austin [Austin], 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), Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), 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 d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), University of California [Berkeley] (UC Berkeley), Département d'Astrophysique (ex SAP) (DAP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, University of Michigan [Ann Arbor], University of Michigan System, University of Hawaii, 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, University of Western Ontario (UWO), University of Cambridge [UK] (CAM), Space Sciences, Technologies and Astrophysics Research Institute (STAR), Université de Liège, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, 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), The Open University [Milton Keynes] (OU), Friedrich-Schiller-Universität = Friedrich Schiller University Jena [Jena, Germany], Université Paris-Saclay, Eureka Scientific, Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Stockholm University, University of Warwick [Coventry], Leiden Observatory [Leiden], Universiteit Leiden, National Astronomical Observatory of Japan (NAOJ), Cornell University [New York], University of Victoria [Canada] (UVIC), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève = University of Geneva (UNIGE), Zentrum für Astronomie der Universität Heidelberg (ZAH), Universität Heidelberg [Heidelberg] = Heidelberg University, GSFC Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center (GSFC), US Naval Research Laboratory, 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), NASA ExoPlanet Science Institute (NExScI), Institute for Astronomy, Department of Physics, ETH Zürich, Ministerio de Ciencia e Innovación (España), European Commission, Hinkley, S [0000-0001-8074-2562], Carter, AL [0000-0001-5365-4815], Ray, S [0000-0003-2259-3911], Millar-Blanchaer, MA [0000-0001-6205-9233], Patapis, P [0000-0001-8718-3732], Perrin, M [0000-0002-3191-8151], Stapelfeldt, K [0000-0002-2805-7338], Wang, J [0000-0003-0774-6502], Ward-Duong, K [0000-0002-4479-8291], Boccaletti, A [0000-0001-9353-2724], Girard, JH [0000-0001-8627-0404], Kalas, P [0000-0002-6221-5360], Kammerer, J [0000-0003-2769-0438], Kervella, P [0000-0003-0626-1749], Leisenring, J [0000-0002-0834-6140], Zhou, Y [0000-0003-2969-6040], Meyer, M [0000-0003-2232-7664], Liu, MC [0000-0003-0241-8956], Absil, O [0000-0002-4006-6237], Bonavita, M [0000-0002-7520-8389], Booth, M [0000-0001-8568-6336], Chen, C [0000-0002-8382-0447], Danielski, C [0000-0002-3729-2663], De Furio, M [0000-0003-1863-4960], Factor, SM [0000-0002-8332-8516], Fortney, JJ [0000-0002-9843-4354], Greenbaum, A [0000-0002-7162-8036], Janson, M [0000-0001-8345-593X], Kenworthy, M [0000-0002-7064-8270], Kuzuhara, M [0000-0002-4677-9182], Martinez, R [0000-0001-6301-896X], Marois, C [0000-0002-4164-4182], Matthews, B [0000-0003-3017-9577], Matthews, EC [0000-0003-0593-1560], Quanz, SP [0000-0003-3829-7412], Rebollido, I [0000-0002-4388-6417], Rickman, E [0000-0003-4203-9715], Samland, M [0000-0001-9992-4067], Sargent, B [0000-0001-9855-8261], Sivaramakrishnan, A [0000-0003-1251-4124], Stone, JM [0000-0003-0454-3718], Tamura, M [0000-0002-6510-0681], Vigan, A [0000-0002-5902-7828], and Apollo - University of Cambridge Repository

Subjects
FOS: Physical sciences, 5109 Space Sciences, Space telescopes, detection-techniques, Exoplanet detection methods, Direct imaging, adaptive optics-instrumentation, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), Earth and Planetary Astrophysics (astro-ph.EP), instrumentation, [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, 5101 Astronomical Sciences, Astrophysics::Earth and Planetary Astrophysics, Coronagraphic imaging, Astrophysics - Instrumentation and Methods for Astrophysics, 51 Physical Sciences, interferometers-planets and satellites, high angular resolution, Exoplanet atmospheres, Astrophysics - Earth and Planetary Astrophysics
Abstract

Full list of authors: Hinkley, Sasha; Carter, Aarynn L.; Ray, Shrishmoy; Skemer, Andrew; Biller, Beth; Choquet, Elodie; Millar-Blanchaer, Maxwell A.; Sallum, Stephanie; Miles, Brittany; Whiteford, Niall; Patapis, Polychronis; Perrin, Marshall; Pueyo, Laurent; Schneider, Glenn; Stapelfeldt, Karl; Wang, Jason; Ward-Duong, Kimberly; Bowler, Brendan P.; Boccaletti, Anthony; Girard, Julien H.; Hines, Dean; Kalas, Paul; Kammerer, Jens; Kervella, Pierre; Leisenring, Jarron; Pantin, Eric; Zhou, Yifan; Meyer, Michael; Liu, Michael C.; Bonnefoy, Mickael; Currie, Thayne; McElwain, Michael; Metchev, Stanimir; Wyatt, Mark; Absil, Olivier; Adams, Jea; Barman, Travis; Baraffe, Isabelle; Bonavita, Mariangela; Booth, Mark; Bryan, Marta; Chauvin, Gael; Chen, Christine; Danielski, Camilla; De Furio, Matthew; Factor, Samuel M.; Fitzgerald, Michael P.; Fortney, Jonathan J.; Grady, Carol; Greenbaum, Alexandra; Henning, Thomas; Hoch, Kielan K. W.; Janson, Markus; Kennedy, Grant; Kenworthy, Matthew; Kraus, Adam; Kuzuhara, Masayuki; Lagage, Pierre-Olivier; Lagrange, Anne-Marie; Launhardt, Ralf; Lazzoni, Cecilia; Lloyd, James; Marino, Sebastian; Marley, Mark; Martinez, Raquel; Marois, Christian; Matthews, Brenda; Matthews, Elisabeth C.; Mawet, Dimitri; Mazoyer, Johan; Phillips, Mark; Petrus, Simon; Quanz, Sascha P.; Quirrenbach, Andreas; Rameau, Julien; Rebollido, Isabel; Rickman, Emily; Samland, Matthias; Sargent, B.; Schlieder, Joshua E.; Sivaramakrishnan, Anand; Stone, Jordan M.; Tamura, Motohide; Tremblin, Pascal; Uyama, Taichi; Vasist, Malavika; Vigan, Arthur; Wagner, Kevin; Ygouf, Marie.--This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/3.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited., The direct characterization of exoplanetary systems with high-contrast imaging is among the highest priorities for the broader exoplanet community. As large space missions will be necessary for detecting and characterizing exo-Earth twins, developing the techniques and technology for direct imaging of exoplanets is a driving focus for the community. For the first time, JWST will directly observe extrasolar planets at mid-infrared wavelengths beyond 5 μm, deliver detailed spectroscopy revealing much more precise chemical abundances and atmospheric conditions, and provide sensitivity to analogs of our solar system ice-giant planets at wide orbital separations, an entirely new class of exoplanet. However, in order to maximize the scientific output over the lifetime of the mission, an exquisite understanding of the instrumental performance of JWST is needed as early in the mission as possible. In this paper, we describe our 55 hr Early Release Science Program that will utilize all four JWST instruments to extend the characterization of planetary-mass companions to ∼15 μm as well as image a circumstellar disk in the mid-infrared with unprecedented sensitivity. Our program will also assess the performance of the observatory in the key modes expected to be commonly used for exoplanet direct imaging and spectroscopy, optimize data calibration and processing, and generate representative data sets that will enable a broad user base to effectively plan for general observing programs in future Cycles. © 2022. The Author(s). Published by IOP Publishing Ltd on behalf of the Astronomical Society of the Pacific (ASP). All rights reserved., This project was supported by a grant from STScI (JWST-ERS-01386) under NASA contract NAS5-03127. M.T.is supported by JSPS KAKENHI Grant No.18H05442. M.B. acknowledges support from the Deutsche Forschungsgemeinschaft (DFG) through grant Kr 2164/13–2. K.W. acknowledges support from NASA through the NASA Hubble Fellowship grant HST-HF2-51472.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555., With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709.

Published
2022
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8. Fast-moving features in the debris disk around AU Microscopii.

Author

Boccaletti A, Thalmann C, Lagrange AM, Janson M, Augereau JC, Schneider G, Milli J, Grady C, Debes J, Langlois M, Mouillet D, Henning T, Dominik C, Maire AL, Beuzit JL, Carson J, Dohlen K, Engler N, Feldt M, Fusco T, Ginski C, Girard JH, Hines D, Kasper M, Mawet D, Ménard F, Meyer MR, Moutou C, Olofsson J, Rodigas T, Sauvage JF, Schlieder J, Schmid HM, Turatto M, Udry S, Vakili F, Vigan A, Wahhaj Z, and Wisniewski J

Abstract

In the 1980s, excess infrared emission was discovered around main-sequence stars; subsequent direct-imaging observations revealed orbiting disks of cold dust to be the source. These 'debris disks' were thought to be by-products of planet formation because they often exhibited morphological and brightness asymmetries that may result from gravitational perturbation by planets. This was proved to be true for the β Pictoris system, in which the known planet generates an observable warp in the disk. The nearby, young, unusually active late-type star AU Microscopii hosts a well-studied edge-on debris disk; earlier observations in the visible and near-infrared found asymmetric localized structures in the form of intensity variations along the midplane of the disk beyond a distance of 20 astronomical units. Here we report high-contrast imaging that reveals a series of five large-scale features in the southeast side of the disk, at projected separations of 10-60 astronomical units, persisting over intervals of 1-4 years. All these features appear to move away from the star at projected speeds of 4-10 kilometres per second, suggesting highly eccentric or unbound trajectories if they are associated with physical entities. The origin, localization, morphology and rapid evolution of these features are difficult to reconcile with current theories.

Published
2015
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9. Flows of gas through a protoplanetary gap.

Author

Casassus S, van der Plas G, Sebastian Perez M, Dent WR, Fomalont E, Hagelberg J, Hales A, Jordán A, Mawet D, Ménard F, Wootten A, Wilner D, Hughes AM, Schreiber MR, Girard JH, Ercolano B, Canovas H, Román PE, and Salinas V

Abstract

The formation of gaseous giant planets is thought to occur in the first few million years after stellar birth. Models predict that the process produces a deep gap in the dust component (shallower in the gas). Infrared observations of the disk around the young star HD 142527 (at a distance of about 140 parsecs from Earth) found an inner disk about 10 astronomical units (AU) in radius (1 AU is the Earth-Sun distance), surrounded by a particularly large gap and a disrupted outer disk beyond 140 AU. This disruption is indicative of a perturbing planetary-mass body at about 90 AU. Radio observations indicate that the bulk mass is molecular and lies in the outer disk, whose continuum emission has a horseshoe morphology. The high stellar accretion rate would deplete the inner disk in less than one year, and to sustain the observed accretion matter must therefore flow from the outer disk and cross the gap. In dynamical models, the putative protoplanets channel outer-disk material into gap-crossing bridges that feed stellar accretion through the inner disk. Here we report observations of diffuse CO gas inside the gap, with denser HCO(+) gas along gap-crossing filaments. The estimated flow rate of the gas is in the range of 7 × 10(-9) to 2 × 10(-7) solar masses per year, which is sufficient to maintain accretion onto the star at the present rate.

Published
2013
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10. Measurement of the flux of ultrahigh energy cosmic rays from monocular observations by the High Resolution Fly's Eye experiment.

Author

Abbasi RU, Abu-Zayyad T, Amann JF, Archbold G, Bellido JA, Belov K, Belz JW, Bergman DR, Cao Z, Clay RW, Cooper MD, Dai H, Dawson BR, Everett AA, Fedorova YA, Girard JH, Gray RC, Hanlon WF, Hoffman CM, Holzscheiter MH, Hüntemeyer P, Jones BF, Jui CC, Kieda DB, Kim K, Kirn MA, Loh EC, Manago N, Marek LJ, Martens K, Martin G, Matthews JA, Matthews JN, Meyer JR, Moore SA, Morrison P, Moosman AN, Mumford JR, Munro MW, Painter CA, Perera L, Reil K, Riehle R, Roberts M, Sarracino JS, Sasaki M, Schnetzer SR, Shen P, Simpson KM, Sinnis G, Smith JD, Sokolsky P, Song C, Springer RW, Stokes BT, Taylor SF, Thomas SB, Thompson TN, Thomson GB, Tupa D, Westerhoff S, Wiencke LR, VanderVeen TD, Zech A, and Zhang X

Abstract

We have measured the cosmic ray spectrum above 10(17.2) eV using the two air-fluorescence detectors of the High Resolution Fly's Eye observatory operating in monocular mode. We describe the detector, phototube, and atmospheric calibrations, as well as the analysis techniques for the two detectors. We fit the spectrum to a model consisting of galactic and extragalactic sources.

Published
2004
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