RADYNVERSION: Learning to Invert a Solar Flare Atmosphere with Invertible Neural Networks
| Autor: | Lyndsay Fletcher, Christopher M. J. Osborne, John A. Armstrong |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Physics
010504 meteorology & atmospheric sciences Solar flare FOS: Physical sciences Astronomy and Astrophysics Astrophysics Plasma Solar physics 01 natural sciences Spectral line law.invention Solar telescope Atmosphere Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science law 0103 physical sciences Physics::Space Physics Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics 010303 astronomy & astrophysics Chromosphere Solar and Stellar Astrophysics (astro-ph.SR) 0105 earth and related environmental sciences Flare |
| ISSN: | 0004-637X 1538-4357 |
| DOI: | 10.48550/arxiv.1901.08626 |
| Popis: | During a solar flare, it is believed that reconnection takes place in the corona followed by fast energy transport to the chromosphere. The resulting intense heating strongly disturbs the chromospheric structure, and induces complex radiation hydrodynamic effects. Interpreting the physics of the flaring solar atmosphere is one of the most challenging tasks in solar physics. Here we present a novel deep learning approach, an invertible neural network, to understanding the chromospheric physics of a flaring solar atmosphere via the inversion of observed solar line profiles in H{\alpha} and Ca II {\lambda}8542. Our network is trained using flare simulations from the 1D radiation hydrodynamics code RADYN as the expected atmosphere and line profile. This model is then applied to single pixels from an observation of an M1.1 solar flare taken with SST/CRISP instrument just after the flare onset. The inverted atmospheres obtained from observations provide physical information on the electron number density, temperature and bulk velocity flow of the plasma throughout the solar atmosphere ranging from 0-10 Mm in height. The density and temperature profiles appear consistent with the expected atmospheric response, and the bulk plasma velocity provides the gradients needed to produce the broad spectral lines whilst also predicting the expected chromospheric evaporation from flare heating. We conclude that we have taught our novel algorithm the physics of a solar flare according to RADYN and that this can be confidently used for the analysis of flare data taken in these two wavelengths. This algorithm can also be adapted for a menagerie of inverse problems providing extremely fast ($\sim$10 {\mu}s) inversion samples. Comment: Published in ApJ |
| Databáze: | OpenAIRE |
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