@DistributionFunction¶
The distribution function module, which defines a distribution function to weigh results with. A number of different types of distribution functions can be generated or loaded in SOFT2, including the analytical primary distribution [1], the analytical avalanche distribution [2], direct output from the kinetic solvers CODE, LUKE and GO+CODE, as well as regular SOFT phase-space distribution functions.
| [1] | (1, 2) Connor and Hastie, 1975 “Relativistic limitations on runaway electrons”. Nuclear Fusion 15 (3), 415 doi:10.1088/0029-5515/15/3/007. |
| [2] | (1, 2) Fülöp et al., 2006 “Destabilization of magnetosonic-whistler waves by a relativistic runaway beam”. Physics of Plasmas 13 (6), 062506 doi:10.1063/1.2208327. |
Note
When specifying distribution functions directly to SOFT, the radial coordinate of the distribution is interpreted as a drift surface label. This is in contrast to the usual radial coordinate in SOFT which is a flux surface label. This means that minor radius \(r=0\) corresponds to the centre of the drift surface when specifying a distribution function to SOFT, and NOT to the magnetic axis as is otherwise the case.
Note also that the radial coordinate in the (green)
RadiationOutput is in fact a flux surface label. Hence, if the same
distribution is applied after a simulation, instead of during a simulation
(using the global distribution_function option), by multiplying it
with a Green’s function, then the radial coordinate of the distribution is
interpreted as a flux surface label.
Types¶
SOFT provides several different types of distribution functions. Which type is configured by a particular block is specified by the “secondary type” of the block, i.e. by giving the type in parentheses after the block name. The available distribution function types are listed in the table below.
| Type | Description |
| (avalanche) | An analytical distribution function based on [2]. |
| (code) | A momentum-space distribution function directly from CODE. |
| (connorhastie) | An analytical distribution function based on [1]. |
| (dream) | Distribution function from the DREAM 1D2P transport solver. |
| (gocode) | GO-CODE distribution function. |
| (luke) | Distribution function from the LUKE 1D2P kinetic solver. |
| (numerical) | A SOFT numerical distribution function. |
| (pitch) | An exponential pitch distribution function. |
| (unit) | A distribution function that is one everywhere. |
Example configuration¶
Please, see the pages for the various distribution function types to view examples of how to configure a distribution function.