Stokes Inversion based on Convolutional Neural Networks
arXiv:1904.03714 · doi:10.1051/0004-6361/201935628
Abstract
Spectropolarimetric inversions are routinely used in the field of Solar Physics for the extraction of physical information from observations. The application to two-dimensional fields of view often requires the use of supercomputers with parallelized inversion codes. Even in this case, the computing time spent on the process is still very large. Our aim is to develop a new inversion code based on the application of convolutional neural networks that can quickly provide a three-dimensional cube of thermodynamical and magnetic properties from the interpretation of two-dimensional maps of Stokes profiles. We train two different architectures of fully convolutional neural networks. To this end, we use the synthetic Stokes profiles obtained from two snapshots of three-dimensional magneto-hydrodynamic numerical simulations of different structures of the solar atmosphere. We provide an extensive analysis of the new inversion technique, showing that it infers the thermodynamical and magnetic properties with a precision comparable to that of standard inversion techniques. However, it provides several key improvements: our method is around one million times faster, it returns a three-dimensional view of the physical properties of the region of interest in geometrical height, it provides quantities that cannot be obtained otherwise (pressure and Wilson depression) and the inferred properties are decontaminated from the blurring effect of instrumental point spread functions for free. The code is provided for free on a specific repository, with options for training and evaluation.
18 pages, 14 figures, accepted for publication in Astronomy & Astrophysics
References in corpus (13)
- An Open Source, Massively Parallel Code for Non-LTE Synthesis and Inversion of Spectral Lines and Zeeman-induced Stokes Profiles
- Advanced Forward Modeling and Inversion of Stokes Profiles Resulting from the Joint Action of the Hanle and Zeeman Effects
- The intensity contrast of solar granulation: comparing Hinode SP results with MHD simulations
- Evidence for Quasi-isotropic Magnetic Fields from Hinode Quiet Sun Observations
- On the validity of the 630 nm Fe I nm lines for the magnetometry of the internetwork quiet Sun
- Three-dimensional structure of a sunspot light bridge
- Sparse inversion of Stokes profiles. I. Two-dimensional Milne-Eddington inversions
- Spatial deconvolution of spectropolarimetric data: an application to quiet Sun magnetic elements
- Spectropolarimetric analysis of an active region filament. I. Magnetic and dynamical properties from single component inversions
- Zeeman-Tomography of the Solar Photosphere -- 3-Dimensional Surface Structures Retrieved from Hinode Observations
- RADYNVERSION: Learning to Invert a Solar Flare Atmosphere with Invertible Neural Networks
- Diagnostic potential of the Ca II 8542A line for solar filaments
- Spectropolarimetric analysis of an active region filament. II. Evidence of the limitations of a single component model