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arXiv · 1904.08390

Recovering Thermodynamics from Spectral Profiles observed by IRIS: A Machine and Deep Learning Approach

Alberto Sainz Dalda·Jaime de la Cruz Rodríguez·Bart De Pontieu·Milan Gošić
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Abstract

Inversion codes allow reconstructing a model atmosphere from observations. With the inclusion of optically thick lines that form in the solar chromosphere, such modelling is computationally very expensive because a non-LTE evaluation of the radiation field is required. In this study, we combine the results provided by these traditional methods with machine and deep learning techniques to obtain similar-quality results in an easy-touse, much faster way. We have applied these new methods to Mg II h&k lines observed by IRIS. As a result, we are able to reconstruct the thermodynamic state (temperature, line-of-sight velocity, non-thermal velocities, electron density, etc.) in the chromosphere and upper photosphere of an area equivalent to an active region in a few CPU minutes, speeding up the process by a factor of $10^5$-$10^6$. The open-source code accompanying this paper will allow the community to use IRIS observations to open a new window to a host of solar phenomena.

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Alberto Sainz Dalda, Jaime de la Cruz Rodríguez, Bart De Pontieu, Milan Gošić. 2019-04-17. Recovering Thermodynamics from Spectral Profiles observed by IRIS: A Machine and Deep Learning Approach. https://doi.org/10.3847/2041-8213%2Fab15d9

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