The SDC now provides the vector magnetic field and line-of-sight velocity data for GRIS spectropolarimeteric observations. This science-ready (Level 2) data is computed using Very Fast Inversion of the Stokes Vector (VFISV, Borrero et al. 2011), a Milne-Eddington inversion code. VFISV carries out pixel-by-pixel inversion of the Stokes profiles for a given spectral line and estimates the line-of-sight velocity, magnetic field strength, along with inclination and azimuth of the magnetic field.
Inversion with the VFISV is now part of the standard GRIS processing pipeline where Level 1 can be automatically processed. The standard data product (L2) now includes the inversions of the spectral line:
- Ca I 10838.970 Å line - for the 10830 Å wavelength region
- Fe I 15662.017 Å line - for the 15650 Å wavelength region
The pipeline code can be used to carry out inversions of other lines. For more information, please check out:
More information about VFISV can be found in the original reference:
Borrero et al, Solar Physics, 2011, 273, 267