SWMF/SP=M-FLAMPA

M-FLAMPA allows us to solve the kinetic equation for SEPs along a multitude of IMF lines originating from the Sun, using time-dependent magnetic field and plasma parameters obtained from the MHD simulation. The model is a high-performance extension of the original FLAMPA code (Sokolov et al. 2004), which simulates SEP distribution along a single field line.

M-FLAMPA solves for the gyrotropic SEP distribution function. The code takes advantage of the fact that particles stay on the same magnetic field line and, therefore, the distribution function may be treated as a function of the distance along the field line, s, rather than a 3D vector. Also, coefficients in the governing equations depend only on background plasma parameters and their Lagrangian derivatives. This important property reduces the problem of particle acceleration in 3D magnetic field into a set of independent 1D problems on continuously evolving Lagrangian grids. In other words, each field line in the model is treated separately from others, which results in a perfectly parallel algorithm.

M-FLAMPA is directly coupled with SC and IH MHD models via an advanced coupling algorithm within the Space Weather Modeling Framework (SWMF). This technique seamlessly connects field lines between the two distinct computational domains, where lines are extracted based on a concurrently updated solution of solar wind parameters. The integrated model traces magnetic field lines from the MHD models to find the area that is covered by field lines originating from a given area of the solar surface, such as an AR. Each field line is represented by a Lagrangian grid that advects with the background plasma in a time-dependent manner. The relevant data at the location of the grid points are transferred to M-FLAMPA, which in turn calculates the evolution of the energetic particle population by solving the governing kinetic equations.

This model needs to couple with the SWMF SC and IH domains to pull magnetic fields and other plasma properties to compute the acceleration.

Output of values along the magnetic field lines.