TomograPy: A Fast, Instrument-Independent, Solar Tomography Software

Abstract

Solar tomography has progressed rapidly in recent years thanks to the development of robust algorithms and the availability of more powerful computers. It can today provide crucial insights in solving issues related to the line-of-sight integration present in the data of solar imagers and coronagraphs. However, there remain challenges such as the increase of the available volume of data, the handling of the temporal evolution of the observed structures, and the heterogeneity of the data in multi-spacecraft studies. We present a generic software package that can perform fast tomographic inversions that scales linearly with the number of measurements, linearly with the length of the reconstruction cube (and not the number of voxels) and linearly with the number of cores and can use data from different sources and with a variety of physical models: TomograPy (http://nbarbey.github.com/TomograPy/), an open-source software freely available on the Python Package Index. For performance, TomograPy uses a parallelized-projection algorithm. It relies on the World Coordinate System standard to manage various data sources. A variety of inversion algorithms are provided to perform the tomographic-map estimation. A test suite is provided along with the code to ensure software quality. Since it makes use of the Siddon algorithm it is restricted to rectangular parallelepiped voxels but the spherical geometry of the corona can be handled through proper use of priors. We describe the main features of the code and show three practical examples of multi-spacecraft tomographic inversions using STEREO/EUVI and STEREO/COR1 data. Static and smoothly varying temporal evolution models are presented.

21 pages, 6 figures, 5 tables

References in corpus (3)

• Magnetic modelling and tomography: First steps towards a consistent reconstruction of the solar corona
• A Time-Evolving 3D Method Dedicated to the Reconstruction of Solar plumes and Results Using Extreme Ultra-Violet Data
• On the importance of background subtraction in the analysis of coronal loops observed with TRACE

Cited by in corpus (8)

• Stereoscopy of extreme UV quiet Sun brightenings observed by Solar Orbiter/EUI
• Newly Discovered Global Temperature Structures in the Quiet Sun at Solar Minimum
• Validation of Spherically Symmetric Inversion by Use of a Tomographic Reconstructed Three-Dimensional Electron Density of the Solar Corona
• Validation of a wave heated 3D MHD coronal-wind model using Polarized Brightness and EUV observations
• Variation of Coronal Activity from the Minimum to Maximum of Solar Cycle 24 using Three Dimensional Coronal Electron Density Reconstructions from STEREO/COR1
• Time-Dependent Tomographic Reconstruction of the Solar Corona
• Data-Optimized Coronal Field Model: I. Proof of Concept
• 3D electron density distributions in the solar corona during solar minima: assessment for more realistic solar wind modeling