Soliton initialisation

add_fdm_soliton!(grids::AbstractGrids, [psi], mass, position, velocity, phase, t0)

Add a fuzzy dark matter soliton to grids. The density profile is rescaled to the desired mass and the phase is set to the desired velocity.

If the argument psi is passed, the soliton is added to the array-like psi rather than than grids.ψx. grids is still used to calculate coordinates.

Note that due to coarse grid effects, the mass of the added soliton may not match the input mass exactly.

The included density profile from comes from PyUltraLight.

Examples

The following script adds a soliton to a grid and checks that the resulting total mass is correct.

using UltraDark
using UltraDark.Initialise

resol = 64
grids = Grids(10.0, resol)

mass = 10.0
position = [0.0, 0.0, 0.0]
velocity = [0.0, 0.0, 0.0]
phase = 0.0
t0 = 0.0

add_fdm_soliton!(grids, mass, position, velocity, phase, t0)

# Ensure density is correct
UltraDark.update_gravitational_potential!(grids, ())

actual_mass = UltraDark.mass(grids)

isapprox(mass, actual_mass, rtol = 1e-3)

# output

true