Physically constrained causal noise models for high-contrast imaging of exoplanets

The detection of exoplanets in high-contrast imaging (HCI) data hinges on post-processing methods to remove spurious light from the host star. So far, existing methods for this task hardly utilize any of the available domain knowledge about the problem explicitly. We propose a new approach to HCI post-processing based on a modified half-sibling regression scheme, and show how we use this framework to combine machine learning with existing scientific domain knowledge. On three real data sets, we demonstrate that the resulting system performs clearly better (both visually and in terms of the SNR) than one of the currently leading algorithms. If further studies can confirm these results, our method could have the potential to allow significant discoveries of exoplanets both in new and archival data.

[1]  B. Macintosh,et al.  Angular Differential Imaging: A Powerful High-Contrast Imaging Technique , 2005, astro-ph/0512335.

[2]  S. Gladysz,et al.  Fainter and closer: finding planets by symmetry breaking. , 2008, Optics express.

[3]  Miguel de Val-Borro,et al.  The Astropy Project: Building an Open-science Project and Status of the v2.0 Core Package , 2018, The Astronomical Journal.

[4]  E E Bloemhof Feasibility of symmetry-based speckle noise reduction for faint companion detection. , 2007, Optics express.

[5]  Brendan P. Bowler,et al.  Imaging Extrasolar Giant Planets , 2016, 1605.02731.

[6]  Gaël Varoquaux,et al.  Scikit-learn: Machine Learning in Python , 2011, J. Mach. Learn. Res..

[7]  Olivier Flasseur,et al.  Exoplanet detection in angular differential imaging by statistical learning of the nonstationary patch covariances , 2018, Astronomy & Astrophysics.

[8]  Julien H. Girard,et al.  Searching for companions down to 2 AU from β Pictoris using the L′-band AGPM coronagraph on VLT/NACO , 2013, 1311.4298.

[9]  Eric E. Bloemhof Speckle noise in highly corrected coronagraphs , 2004, SPIE Optics + Photonics.

[10]  Prasanth H. Nair,et al.  Astropy: A community Python package for astronomy , 2013, 1307.6212.

[11]  Daniel Foreman-Mackey,et al.  A pixel-level model for event discovery in time-domain imaging , 2017, 1710.02428.

[12]  E. Bloemhof,et al.  Anomalous intensity of pinned speckles at high adaptive correction. , 2004, Optics letters.

[13]  Eric E. Bloemhof Remnant Speckles in a Highly Corrected Coronagraph , 2004 .

[14]  Michael Wegner,et al.  Ground-based and Airborne Instrumentation for Astronomy III , 2010 .

[15]  Dimitri Mawet,et al.  A New Standard for Assessing the Performance of High Contrast Imaging Systems , 2017, 1711.01215.

[16]  Russell B. Makidon,et al.  The Structure of High Strehl Ratio Point-Spread Functions , 2003 .

[17]  Tomas Stolker,et al.  PynPoint: a modular pipeline architecture for processing and analysis of high-contrast imaging data , 2018, Astronomy & Astrophysics.

[18]  Eric E. Bloemhof Suppression of Speckle Noise by Speckle Pinning in Adaptive Optics , 2003 .

[19]  Remko Stuik,et al.  Status of the mid-infrared E-ELT imager and spectrograph METIS , 2016, Astronomical Telescopes + Instrumentation.

[20]  T. Henning,et al.  TRAP: a temporal systematics model for improved direct detection of exoplanets at small angular separations , 2020, 2011.12311.

[21]  E. Speckle noise in highly corrected coronagraphs , .

[22]  D. Mouillet,et al.  Direct exoplanet detection and characterization using the ANDROMEDA method: Performance on VLT/NaCo data , 2015, 1508.06406.

[23]  Eric E. Bloemhof Suppression of speckles at high adaptive correction using speckle symmetry , 2006, SPIE Optics + Photonics.

[24]  Bruce A. Macintosh,et al.  Speckle Decorrelation and Dynamic Range in Speckle Noise-limited Imaging , 2002 .

[25]  C. Marois,et al.  A NEW ALGORITHM FOR POINT SPREAD FUNCTION SUBTRACTION IN HIGH-CONTRAST IMAGING: A DEMONSTRATION WITH ANGULAR DIFFERENTIAL IMAGING , 2007 .

[26]  K. Jarrod Millman,et al.  Array programming with NumPy , 2020, Nat..

[27]  Bertrand Mennesson,et al.  FUNDAMENTAL LIMITATIONS OF HIGH CONTRAST IMAGING SET BY SMALL SAMPLE STATISTICS , 2014, 1407.2247.

[28]  Julien H. Girard,et al.  The near-infrared spectral energy distribution of β Pictoris b , 2013, 1302.1160.

[29]  Bernhard Schölkopf,et al.  Modeling confounding by half-sibling regression , 2016, Proceedings of the National Academy of Sciences.

[30]  R. Soummer,et al.  DETECTION AND CHARACTERIZATION OF EXOPLANETS AND DISKS USING PROJECTIONS ON KARHUNEN–LOÈVE EIGENIMAGES , 2012, 1207.4197.

[31]  Eric E. Bloemhof Speckles in a highly corrected adaptive optics system , 2003, SPIE Optics + Photonics.

[32]  S. P. Littlefair,et al.  THE ASTROPY PROJECT: BUILDING AN INCLUSIVE, OPEN-SCIENCE PROJECT AND STATUS OF THE V2.0 CORE PACKAGE , 2018 .

[33]  Vanessa P. Bailey,et al.  Improving and Assessing Planet Sensitivity of the GPI Exoplanet Survey with a Forward Model Matched Filter , 2017, 1705.05477.

[34]  D. Fantinel,et al.  ERIS: revitalising an adaptive optics instrument for the VLT , 2018, Astronomical Telescopes + Instrumentation.

[35]  Markus J. Bonse,et al.  Wavelet based speckle suppression for exoplanet imaging - Application of a de-noising technique in the time domain , 2018, 1804.05063.

[36]  Pierre Riaud,et al.  Speckle Symmetry with High-Contrast Coronagraphs , 2002 .

[37]  Joel Nothman,et al.  SciPy 1.0-Fundamental Algorithms for Scientific Computing in Python , 2019, ArXiv.

[38]  Adam Amara,et al.  PYNPOINT: An image processing package for finding exoplanets , 2012, 1207.6637.

[39]  Tiffany Meshkat,et al.  Two Directly Imaged, Wide-orbit Giant Planets around the Young, Solar Analog TYC 8998-760-1 , 2020, The Astrophysical Journal.

[40]  Wes McKinney,et al.  Data Structures for Statistical Computing in Python , 2010, SciPy.

[41]  John D. Hunter,et al.  Matplotlib: A 2D Graphics Environment , 2007, Computing in Science & Engineering.

[42]  Pierrick Coupé,et al.  MRI noise estimation and denoising using non-local PCA , 2015, Medical Image Anal..

[43]  Marc Van Droogenbroeck,et al.  Low-rank plus sparse decomposition for exoplanet detection in direct-imaging ADI sequences. The LLSG algorithm , 2016, 1602.08381.

[44]  Marc Van Droogenbroeck,et al.  Supervised detection of exoplanets in high-contrast imaging sequences , 2017, 1712.02841.

[45]  Sascha P. Quanz,et al.  Direct detection of exoplanets in the 3–10 μm range with E-ELT/METIS , 2014, International Journal of Astrobiology.

[46]  Birte U. Forstmann,et al.  Denoising High-Field Multi-Dimensional MRI With Local Complex PCA , 2019, bioRxiv.

[47]  Eric E. Bloemhof,et al.  Behavior of Remnant Speckles in an Adaptively Corrected Imaging System , 2001 .

[48]  E E Bloemhof Static point-spread function correction dominating higher-order speckle terms at high adaptive correction. , 2004, Optics letters.

[49]  Eric E. Bloemhof Statistics of remnant speckles in an adaptively corrected imaging system , 2002, SPIE Optics + Photonics.

[50]  et al.,et al.  Jupyter Notebooks - a publishing format for reproducible computational workflows , 2016, ELPUB.