Green’s function output

SOFT is capable of generating so-called Green’s functions.

Important points

For Green’s function output, the (green) module must be used. It requires at least two parameters to be specified: @RadiationOutput(green) format (specifying the dependences of the Green’s function), and @RadiationOutput(green) output (name of output file).

The format option is a string consisting of any sequence of the following six characters:

Format	Description
1	(Alphabetically) first momentum parameter.
2	(Alphabetically) second momentum parameter.
i	Vertical pixel dimension.
j	Horizontal pixel dimension.
r	Radial parameter.
w	Radiation spectrum.

Dominant particles

Example configuration

The following generates a Green’s function \(G(p_\parallel, p_\perp)\):

# Generate a momentum-space
# Green's function.
##############################

magnetic_field     = mf;
tools              = rad;

# Configuration of EAST-like magnetic equilibrium
@MagneticField mf (analytical) {
    B0     = 5;     # On-axis field strength (T)
    Rm     = 0.68;  # Major radius (m)
    rminor = 0.22;  # Minor radius (m)

    # Safety-factor
    qtype  = linear;
    qa1    = 2;
    qa2    = 1;
}

# Phase space grid
@ParticleGenerator PGen {
    a      = 0.0, 0.95, 20; # Normalized minor radius
    ppar   = -2, -165, 40;     # Parallel momentum (mc)
    pperp  = 1, 15, 40;    # Perpendicular momentum (mc)

    progress = 10;
}

# Orbit generator
@ParticlePusher PPusher {
    nt = 2000;        # Number of timesteps per orbit (resolution parameter)
}

# Radiation tool
@Radiation rad {
    detector = det;

    ntoroidal   = 7000;    # No. of toroidal sections in tokamak (resolution parameter)
    model       = cone;    # Radiation model to use
    output      = green;   # List of configuration of output
}

# Detector properties
# Set up a tangentially viewing HXR camera.
@Detector det {
    aperture     = 0.006;
    position     = 0.68, -0.68, 0;
    direction    = 0, 1, 0;
    vision_angle = 0.78 fov;
    spectrum     = no;
}

# Radiation model
@RadiationModel cone (cone) {
    emission = synchrotron;
}

@RadiationOutput green (green) {
    format = 12;
    output = "data/green.mat";
}