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Fast and Accurate Emulation of the SDO/HMI Stokes Inversion with Uncertainty Quantification

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 نشر من قبل Richard Higgins
 تاريخ النشر 2021
  مجال البحث فيزياء
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The Helioseismic and Magnetic Imager (HMI) onboard NASAs Solar Dynamics Observatory (SDO) produces estimates of the photospheric magnetic field which are a critical input to many space weather modelling and forecasting systems. The magnetogram products produced by HMI and its analysis pipeline are the result of a per-pixel optimization that estimates solar atmospheric parameters and minimizes disagreement between a synthesized and observed Stokes vector. In this paper, we introduce a deep learning-based approach that can emulate the existing HMI pipeline results two orders of magnitude faster than the current pipeline algorithms. Our system is a U-Net trained on input Stokes vectors and their accompanying optimization-based VFISV

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