Including Helium in 1-D Radiative Transfer Calculations¶
Test #2 from the Radiative Transfer Comparison Project (Iliev et al. 2006).
This problem investigates the growth of an HII region around a blackbody source of ionizing photons. The main parameters are:
Stellar ionizing photon production rate of \(\dot{Q} = 5 \times 10^{48} \ \text{s}^{-1}\).
Stellar spectrum is a \(10^5\) K blackbody.
Medium composed of hydrogen only, with a density of \(n_{\text{H}} = 10^{-3} \ \text{cm}^{-3}\).
Gas temperature is able to evolve. It is initially set to \(T=100\) K everywhere on the grid.
The ionization and heating rates are computed treating the source’s spectral energy distribution in full. A lengthy discussion of this can be found in Mirocha et al. (2012).
Including helium for pre-existing problem types is as simple as adding 10 to
the problem_type
, i.e.,
import ares
sim = ares.simulations.RaySegment(problem_type=12)
sim.run()
Now, we initialize an instance of the appropriate analysis class:
and have a look at the temperature profile at 10, 30, and 100 Myr,
ax1 = sim.RadialProfile('Tk', t=[10, 30, 100])
radial profiles of the hydrogen species fractions,
ax2 = sim.RadialProfile('h_1', t=[10, 30, 100], fig=2)
sim.RadialProfile('h_2', t=[10, 30, 100], ax=ax2, ls='--')
and the species fractions for helium:
ax3 = sim.RadialProfile('he_1', t=[10, 30, 100], fig=3)
sim.RadialProfile('he_2', t=[10, 30, 100], ax=ax3, ls='--')
sim.RadialProfile('he_3', t=[10, 30, 100], ax=ax3, ls=':')