GDF

Slepian based reconstruction of solar wind particle distributions

GDF or Gyrotropic Distribution Functions are a commonly used approximation for solar wind velocity distribution functions (VDFs). This repository uses Slepian basis function based reconstructions to recover distribution functions from Parker Solar Probe's SPAN-Ai instrument. This repository is an extension of vdfit which was designed for reconstructing agyritropic MMS and Solar Orbiter VDFs to the PSP measurements.

Note

This project is under active development. The next goal is to integrate Solar Probe Cup measurements to jointly constraint the GDF reconstructions.

Attribution

Please cite Bharati Das & Terres (2025) if you find this code useful in your research. The BibTeX entry for the paper is:

@ARTICLE{2025ApJ...982...96B,
       author = {{Bharati Das}, Srijan and {Terres}, Michael},
        title = "{Recovering Ion Distribution Functions. I. Slepian Reconstruction of Velocity Distribution Functions from MMS and Solar Orbiter}",
      journal = {\apj},
     keywords = {Space plasmas, Solar wind, Regression, Solar instruments, 1544, 1534, 1914, 1499, Astrophysics - Solar and Stellar Astrophysics, Physics - Space Physics},
         year = 2025,
        month = apr,
       volume = {982},
       number = {2},
          eid = {96},
        pages = {96},
          doi = {10.3847/1538-4357/adb6a0},
archivePrefix = {arXiv},
       eprint = {2501.17294},
 primaryClass = {astro-ph.SR},
       adsurl = {https://ui.adsabs.harvard.edu/abs/2025ApJ...982...96B},
      adsnote = {Provided by the SAO/NASA Astrophysics Data System}
}