torchmfbd carries out multi-object multi-frame blind deconvolution (MOMFBD) of point-like or extended objects, and is especially tailored to solar images. The code is built on PyTorch and provides a high-level interface for adding observations, defining phase diversity channels, and adding regularization. It can deal with spatially variant PSFs either by mosaicking the images or by defining a spatially variant PSF. torchmfbd supports smooth solutions and solutions based on the ℓ 1 penalization of the isotropic undecimated wavelet transform of the object, and regularizations are easily extendable. The code also includes an API and a configuration file.

SICON (Stokes Inversion based on COnvolutional Neural networks) provides a three-dimensional cube of thermodynamical and magnetic properties from the interpretation of two-dimensional maps of Stokes profiles by use of a convolutional neural network. In addition to being much faster than parallelized inversion codes, SICON, when trained on synthetic Stokes profiles from two numerical simulations of different structures of the solar atmosphere, also provided a three-dimensional view of the physical properties of the region of interest in geometrical height, and pressure and Wilson depression properties that are decontaminated from the blurring effect of instrumental point spread functions.

MOLPOP-CEP calculates the exact solution of radiative transfer problems in multi-level atomic systems. The radiative transfer equations are analytically integrated to reduce the final problem to the solution of a non-linear algebraic system of equations in the level populations. The code uses Coupled Escape Probability formalism to analytically solve the radiative transfer. Written in Fortran 90, MOLPOP-CEP is limited to plane-parallel slabs that can present arbitrary spatial variations of the physical conditions.

A big challenge in solar and stellar physics in the coming years will be to decipher the magnetism of the solar outer atmosphere (chromosphere and corona) along with its dynamic coupling with the magnetic fields of the underlying photosphere. To this end, it is important to develop rigorous diagnostic tools for the physical interpretation of spectropolarimetric observations in suitably chosen spectral lines. HAZEL is a computer program for the synthesis and inversion of Stokes profiles caused by the joint action of atomic level polarization and the Hanle and Zeeman effects in some spectral lines of diagnostic interest, such as those of the He I 1083.0 nm and 587.6 nm (or D3) multiplets. It is based on the quantum theory of spectral line polarization, which takes into account in a rigorous way all the relevant physical mechanisms and ingredients (optical pumping, atomic level polarization, level crossings and repulsions, Zeeman, Paschen-Back and Hanle effects). The influence of radiative transfer on the emergent spectral line radiation is taken into account through a suitable slab model. The user can either calculate the emergent intensity and polarization for any given magnetic field vector or infer the dynamical and magnetic properties from the observed Stokes profiles via an efficient inversion algorithm based on global optimization methods.