Vlasiator - ten letters you can count on
Space weather is a term used to describe the variable environmental effects within near-Earth space, caused by the Sun emitting solar wind, a stream of charged particles carrying the solar electromagnetic field. Space weather can be caused by solar high-energy particles or by dynamic variations of the solar wind that can cause extended periods of major disturbances on ground and space, affecting technological systems (e.g., telecommunication and weather spacecraft at geostationary orbit, and ground-based power grids).
In Vlasiator, ions are represented as velocity distribution functions, while electrons are magnetohydrodynamic fluid, enabling a self-consistent global plasma simulation that can describe multi-temperature plasmas to resolve non-MHD processes that currently cannot be self-consistently described by the existing global space weather simulations. The novelty is that by modelling ions as velocity distribution functions the outcome will be numerically noiseless.
Due to the multi-dimensional approach at ion scales, Vlasiator's computational challenges are immense. We use advanced high performance computing techniques to allow massively parallel computations on tens of thousands of cores.
See the wiki for build instructions and general advice.
- Palmroth, M., Ganse, U., Pfau-Kempf, Y., Battarbee, M., Turc, L., Brito, T., Grandin, M., Hoilijoki, S., Sandroos, A. & von Alfthan, S. (2018). Vlasov methods in space physics and astrophysics. Living Reviews in Computational Astrophysics, 4, 1. doi: 10.1007/s41115-018-0003-2
- von Alfthan, S., Pokhotelov, D., Kempf, Y., Hoilijoki, S., Honkonen, I., Sandroos, A. & Palmroth, M. (2014). Vlasiator: First global hybrid-Vlasov simulations of Earth's foreshock and magnetosheath . Journal of Atmospheric and Solar-Terrestrial Physics , 120, 24 - 35. doi: http://dx.doi.org/10.1016/j.jastp.2014.08.012