Astronomy

PACO ASDI: an algorithm for exoplanet detection and characterization in direct imaging with integral field spectrographs

*Context.* Exoplanet detection and characterization by direct imaging both rely on sophisticated instruments (adaptive optics and coronagraph) and adequate data processing methods. Angular and spectral differential imaging (ASDI) combines …

Exoplanet detection in direct imaging by statistical learning of the non-stationary patch covariances

We have recently introduced a new method dedicated to source detection from angular differential imaging (ADI) data: PACO (for PAtch COvariances). Data reduction in ADI is challenging because the faint point sources are hidden in a stronger …

Object detection and characterization from faint signals in images: applications in astronomy and microscopy

Detecting and characterizing objects in images in the low signal-to-noise ratio regime is a critical issue in many areas such as astronomy or microscopy. In astronomy, the detection of exoplanets and their characterization by direct imaging from the …

Robustness to bad frames in angular differential imaging: a local weighting approach

*Context.* The detection of exoplanets by direct imaging is very challenging. It requires an extreme adaptive-optics (AO) system and a coronagraph as well as suitable observing strategies. In angular differential imaging, the signal-to-noise ratio is …

VLT/SPHERE exploration of the young multiplanetary system PDS70

*Context.* PDS 70 is a young (5.4 Myr), nearby (~113 pc) star hosting a known transition disk with a large gap. Recent observations with SPHERE and NACO in the near-infrared (NIR) allowed us to detect a planetary mass companion, PDS 70 b, within the …

Exoplanet detection in direct imaging by statistical learning of the non-stationary patch covariances – The PACO-based algorithms

We have recently introduced a new method dedicated to source detection from angular differential imaging (ADI) data: PACO (for PAtch COvariances). Data reduction in ADI is challenging because the faint point sources are hidden in a stronger …

Détection d’exoplanètes par une modélisation statistique locale de la covariance spatio-temporelle du fond

La détection d’exoplanètes par imagerie directe est une tâche ardue : le faible signal des objets d’intérêt est noyé dans un fond spatialement très structuré, dû à l’étoile hôte. Seule la combinaison de plusieurs observations permet de distinguer le …

Determining mass limits around HD 163296 through SPHERE direct imaging data

HD 163296 is a Herbig Ae/Be star known to host a protoplanetary disk with a ringed structure. To explain the disk features, previous works proposed the presence of planets embedded into the disk. We have observed HD 163296 with the near-infrared …

Detection and characterization of faint signals in images : application in astronomy and microscopy

An unsupervised patch-based approach for exoplanet detection by direct imaging. The PACO algorithm