Fractional Abundances¶
Here we compute the fractional abundances for Neon ions, assuming the coronal equilibrium model. Let us plot the fractional abundances varying with the temperature for a fixed electron density.
[1]:
import numpy as np
import ultraplot as uplt
from cherab.core.atomic.elements import neon
from cherab.imas.ids.common import solve_coronal_equilibrium
from cherab.openadas import OpenADAS
from cherab.openadas.install import install_adf11acd, install_adf11scd
09:19:57 CRITICAL Could not import 'imas_core': No module named 'imas_core'. Some functionality is not available. @imas_interface.py:34
Download the necessary atomic data from OpenADAS if not already available.
[2]:
atomic_data = OpenADAS(permit_extrapolation=True, missing_rates_return_null=False)
try:
atomic_data.ionisation_rate(neon, 1)
except RuntimeError:
install_adf11acd(neon, "adf11/acd96/acd96_ne.dat", download=True)
install_adf11scd(neon, "adf11/scd96/scd96_ne.dat", download=True)
Installing adf11/acd96/acd96_ne.dat...
- downloading ADF file 'adf11/acd96/acd96_ne.dat' to '/home/runner/.cherab/openadas/repository/_download_cache/adf11/acd96/acd96_ne.dat'
Installing adf11/scd96/scd96_ne.dat...
- downloading ADF file 'adf11/scd96/scd96_ne.dat' to '/home/runner/.cherab/openadas/repository/_download_cache/adf11/scd96/scd96_ne.dat'
Set the electron density and the range of electron temperatures.
[3]:
ELECTRON_DENSITY = 1e19
electron_temperatures = np.logspace(-0.2, 3.2, 100)
The .solve_coronal_equilibrium function computes the fractional abundances by setting the total density to one.
[4]:
abundances = solve_coronal_equilibrium(
neon,
np.ones_like(electron_temperatures),
np.full_like(electron_temperatures, ELECTRON_DENSITY),
electron_temperatures,
atomic_data=atomic_data,
)
Plot the fractional abundances as a function of the electron temperature.
[5]:
fig, ax = uplt.subplots(refaspect=1.2, refwidth=4)
lines = ax.plot(
electron_temperatures,
abundances.T,
cycle="tab20",
)
ax.legend(
lines,
[f"Ne {i}+" for i in range(neon.atomic_number + 1)],
ncols=1,
loc="right",
frame=False,
fontcolor="w",
)
ax.format(
style="dark_background",
xscale="log",
yformatter=("percent", 1),
tickminor=True,
tickdir="in",
grid=True,
gridalpha=0.3,
xlabel="Electron Temperature [eV]",
title=r"Fractional Abundances, $n_\mathrm{e} = 10^{19}$ m$^{-3}$",
)
/home/runner/work/imas/imas/.pixi/envs/docs/lib/python3.14/site-packages/ultraplot/__init__.py:84: UltraPlotWarning: Rebuilding font cache. This usually happens after installing or updating ultraplot.
register_fonts(default=True)
