Explanipedia

Coherent differential imaging of high-contrast extended sources with VLT/SPHERE Open

Axel Potier, R. Galicher, Pierre Baudoz, Johan Mazoyer, Z. Wahhaj , et al. · 2025

Context . High-contrast imaging relies on advanced coronagraphs and adaptive optics (AO) to attenuate the starlight. However, residual aberrations, especially non-common path aberrations between the AO channel and the coronagraph channel, …

GPI+SPHERE detection of a 6.1 MJup circumbinary planet around HD 143811 Open

V. Squicciarini, Johan Mazoyer, C. Wilkinson, A. M. Lagrange, P. Delorme , et al. · 2025

Context. Owing to its sensitivity to wide-orbit giant exoplanets, direct imaging is uniquely positioned to shed light on the interplay between protoplanetary disks and stellar hosts. In addition to constraining formation models, new detect…

Optimising reference library selection for reference-star differential imaging of discs with SPHERE/IRDIS Open

S. Stasevic, J. Milli, Johan Mazoyer, A.-M. Lagrange, S. Bergeon · 2025

Context. The direct detection of circumstellar discs through high-contrast imaging provides key insights into the history and dynamics of planetary systems. Pole-on discs, especially faint debris discs, are difficult to detect and require …

Evidence for a sub-Jovian planet in the young TWA 7 disk Open

A.‐M. Lagrange, C. Wilkinson, Mathilde Mâlin, A. Boccaletti, C. Perrot , et al. · 2025

Planets are thought to form from dust and gas in protoplanetary disks, with debris disks being the remnants of planet formation. Aged a few million up to a few billion years, debris disks have lost their primordial gas, and their dust is p…

The Disks In Scorpius–Centaurus Survey (DISCS). I. Four Newly Resolved Debris Disks in Polarized Intensity Light Open

Justin Hom, Thomas M. Esposito, Katie A. Crotts, Gaspard Duchêne, Jennifer Patience , et al. · 2025

The presence of infrared excesses around stars directly correlates with spatially resolved imaging detections of circumstellar disks at both millimeter and optical/near-infrared wavelengths. High-contrast imagers have resolved dozens of ci…

Dust populations from 30 to 1000 au in the debris disk of HD 120326 Open

C. Desgrange, J. Milli, G. Chauvin, M. Bonnefoy, Th. Henning , et al. · 2025

Context. To date, more than a hundred debris disks have been spatially resolved. Among them, the young system HD 120326 stands out, displaying different disk substructures on both intermediate (30–150 au) and large (150–1000 au) scales. Ai…

Extended linearity in the high-order wavefront sensor for the Roman Coronagraph Open

Iva Laginja, Pierre Baudoz, Johan Mazoyer, Axel Potier, Raphaël Galicher , et al. · 2025

Context . The aim of the Coronagraphic Instrument (CGI) on board the Roman Space Telescope is to achieve unprecedented levels of contrast for the direct imaging of exoplanets, which will serve as a critical technology demonstrator for futu…

Dust populations from 30 to 1000 au in the debris disk of HD 120326 Open

C. Desgrange, J. Milli, G. Chauvin, M. Bonnefoy, Th. Henning , et al. · 2025

Context. To date, more than a hundred debris disks have been spatially resolved. Among them, the young system HD 120326 stands out, displaying different disk substructures on both intermediate (30-150 au) and large (150-1000 au) scales. Ai…

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems. III. Aperture Masking Interferometric Observations of the Star HIP 65426 at 3.8 μm Open

Shrishmoy Ray, Steph Sallum, Sasha Hinkley, Anand Sivaramkrishnan, Rachel Cooper , et al. · 2025

We present aperture masking interferometry (AMI) observations of the star HIP 65426 at 3.8 μ m, as part of the JWST Direct Imaging Early Release Science program, obtained using the Near Infrared Imager and Slitless Spectrograph instrument.…

The SPHERE infrared survey for exoplanets (SHINE) Open

A. Chomez, P. Delorme, A. M. Lagrange, R. Gratton, Olivier Flasseur , et al. · 2025

Context. Over the past decade, large surveys with state-of-the-art planet-finder instruments such as Spectro-Polarimetric High-contrast Exoplanet REsearch on board Very Large Telescope (SPHERE@VLT), coupled with coronagraphic devices and e…

Extended Linearity in the High-Order Wavefront Sensor for the Roman Coronagraph Open

Iva Laginja, Pierre Baudoz, Johan Mazoyer, Axel Potier, Raphaël Galicher , et al. · 2025

Context. The Coronagraphic Instrument (CGI) on the Roman Space Telescope aims for unprecedented contrast for direct imaging of exoplanets, serving as a critical tech demo for future missions like the Habitable Worlds Observatory. This requ…

Advancing European high-contrast imaging R&D towards the Habitable Worlds Observatory Open

Iva Laginja, Óscar Carrión-González, Romain Laugier, Elisabeth C. Matthews, Lucie Leboulleux , et al. · 2025

The SPHERE infrared survey for exoplanets (SHINE). V. Complete observations, data reduction and analysis, detection performances, and final results Open

A. Chomez, P. Delorme, A.‐M. Lagrange, R. Gratton, Olivier Flasseur , et al. · 2025

During the past decade, state-of-the-art planet-finder instruments like SPHERE@VLT, coupling coronagraphic devices and extreme adaptive optics systems, unveiled, thanks to large surveys, around 20 planetary mass companions at semi-major ax…

Searching for substellar companion candidates with Gaia. III. Search for companions to members of young associations Open

A. M. Lagrange, F. Kiefer, P. Rubini, V. Squicciarini, A. Chomez , et al. · 2025

Absolute astrometry with Gaia is expected to detect and characterize the orbits of thousands of exoplanets in the coming years. A tool, GaiaPMEX, was recently developed to characterize multiple systems based on Gaia-only data, and, when po…

The COBREX archival survey: Improved constraints on the occurrence rate of wide-orbit substellar companions Open

V. Squicciarini, Johan Mazoyer, A. M. Lagrange, A. Chomez, P. Delorme , et al. · 2024

Context . Direct imaging (DI) campaigns are uniquely suited to probing the outer regions around young stars in pursuit of giant exoplanet and brown dwarf companions, providing key complementary information to radial velocity (RV) and trans…

Breaking degeneracies in exoplanetary parameters through self-consistent atmosphere–interior modelling Open

C. Wilkinson, B. Charnay, S. Mazevet, A.-M. Lagrange, A. Chomez , et al. · 2024

Context . With a new generation of observational instruments largely dedicated to exoplanets (i.e. JWST, ELTs, PLATO, and Ariel) providing atmospheric spectra and mass and radius measurements for large exoplanet populations, the planetary …

The COBREX archival survey: improved constraints on the occurrence rate of wide-orbit substellar companions. I. A uniform re-analysis of 400 stars from the GPIES survey Open

V. Squicciarini, Johan Mazoyer, A.-M. Lagrange, A. Chomez, P. Delorme , et al. · 2024

Direct imaging (DI) campaigns are uniquely suited to probing the outer regions around young stars and looking for giant exoplanet and brown dwarf companions, hence providing key complementary information to radial velocity (RV) and transit…

Exoplanet Imaging Data Challenge, phase II: Comparison of algorithms in terms of characterization capabilities Open

F. Cantalloube, Valentin Christiaens, Carles Cantero Mitjans, Anthony Cioppa, E. Nasedkin , et al. · 2024

In this communication, we report on the results of the second phase of the Exoplanet Imaging Data Challenge started in 2019. This second phase focuses on the characterization of point sources (exoplanet signals) within multispectral high-c…

Breaking degeneracies in exoplanetary parameters through self-consistent atmosphere-interior modelling Open

Christian Wilkinson, Benjamin Charnay, S. Mazevet, A.‐M. Lagrange, A. Chomez , et al. · 2024

Context: A new generation of instruments (e.g., JWST, ELTs, PLATO and Ariel) is providing atmospheric spectra and mass/radius measurements for large exoplanet populations, challenging planetary models used to interpret these findings. Aims…

Gemini Planet Imager Observations of a Resolved Low-inclination Debris Disk around HD 156623 Open

B. Lewis, Michael P. Fitzgerald, Thomas M. Esposito, Pauline Arriaga, Ronald López , et al. · 2024

The 16 Myr old A0V star HD 156623 in the Scorpius–Centaurus association hosts a high-fractional-luminosity debris disk, recently resolved in scattered light for the first time by the Gemini Planet Imager (GPI) in polarized intensity only. …

Exoplanet imaging data challenge, phase II: comparison of algorithms in terms of characterization capabilities Open

F. Cantalloube, Valentin Christiaens, Carlos Alberto Torres-Cantero, Anthony Cioppa, E. Nasedkin , et al. · 2024

International audience

Revisiting the Borde-Traub focal plane wavefront estimation technique for exoplanet direct imaging Open

Axel Potier, A. J. Eldorado Riggs, Garreth Ruane, Phillip K. Poon, Matthew Noyes , et al. · 2024

Direct imaging of exoplanets relies on complex wavefront sensing and control architectures. In addition to fast adaptive optics systems, most of the future high-contrast imaging instruments will soon be equipped with focal plane wavefront …

A deep reinforcement learning approach to wavefront control for exoplanet imaging Open

Yann Gutierrez, Johan Mazoyer, Olivier Herscovici-Schiller, Laurent M. Mugnier, B. Abeloos , et al. · 2024

International audience

A Deep Reinforcement Learning Approach to Wavefront Control for Exoplanet Imaging Open

Yann Gutierrez, Johan Mazoyer, Olivier Herscovici-Schiller, Laurent M. Mugnier, B. Abeloos , et al. · 2024

Exoplanet imaging uses coronagraphs to block out the bright light from a star, allowing astronomers to observe the much fainter light from planets orbiting the star. However, these instruments are heavily impacted by small wavefront aberra…

Gemini Planet Imager Observations of a Resolved Low-Inclination Debris Disk Around HD 156623 Open

B. Lewis, Michael P. Fitzgerald, Thomas M. Esposito, Pauline Arriaga, Ronald López , et al. · 2024

The 16 Myr-old A0V star HD 156623 in the Scorpius--Centaurus association hosts a high-fractional-luminosity debris disk, recently resolved in scattered light for the first time by the Gemini Planet Imager (GPI) in polarized intensity. We p…

Numerical simulations for the SAXO+ upgrade: Performance analysis of the adaptive optics system Open

C. Goulas, R. Galicher, F. Vidal, Johan Mazoyer, Florian Ferreira , et al. · 2024

Context. SPHERE, operating at the VLT since 2014, is currently one of the high-contrast instruments with a higher performance. Its adaptive optics system, known as SAXO, will be upgraded to SAXO+, which features the addition of a second st…

Upgrading SPHERE with the second stage AO system SAXO+: non-common path aberrations estimation and correction Open

Johan Mazoyer, Charles Goulas, Fabrice Vidal, Isaac Bernardino Dinis, J. Milli , et al. · 2024

editorial reviewed

Image-based wavefront correction using model-free Reinforcement Learning Open

Yann Gutierrez, Johan Mazoyer, Laurent M. Mugnier, Olivier Herscovici-Schiller, B. Abeloos · 2024

Optical aberrations prevent telescopes from reaching their theoretical diffraction limit. Once estimated, these aberrations can be compensated for using deformable mirrors in a closed loop. Focal plane wavefront sensing enables the estimat…

Upgrading SPHERE with the second stage AO system SAXO+: non-common path aberrations estimation and correction Open

Johan Mazoyer, Charles Goulas, Fabrice Vidal, Isaac Bernardino Dinis, J. Milli , et al. · 2024

SAXO+ is a planned enhancement of the existing SAXO, the VLT/ SPHERE adaptive optics system, deployed on ESO's Very Large Telescope. This upgrade is designed to significantly enhance the instrument's capacity to detect and analyze young Ju…

Numerical simulations for the SAXO+ upgrade: Performance analysis of the adaptive optics system Open

Charles Goulas, Raphaël Galicher, Fabrice Vidal, Johan Mazoyer, Florian Ferreira , et al. · 2024

SPHERE, operating at the VLT since 2014, is currently one of the high-contrast instruments with a higher performance. Its adaptive optics system, known as SAXO, will be upgraded to SAXO+, which features the addition of a second stage of ad…

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