Diffuse Ionized Gas in Simulations of Multiphase, Star-forming Galactic Disks

摘要: It has been hypothesized that photons from young, massive star clusters are responsible for maintaining the ionization of diffuse warm ionized gas seen in both Milky Way and other disk galaxies. For a theoretical investigation medium (WIM), it is crucial to solve radiation transfer equations where ISM modeled self-consistently. To this end, we employ Solar neighborhood model TIGRESS, magnetohydrodynamic simulation multiphase, star-forming ISM, post-process with an adaptive ray tracing method UV clusters. We find WIM volume filling factor highly variable, sensitive rate ionizing photon production structure. The mean rises ~0.15 at |z|~1 kpc. Approximately half absorbed by dust; cumulative escape fraction 1.1%. Our time-averaged synthetic H$\alpha$ line profile matches WHAM observations on redshifted (outflowing) side, but insufficient intensity blueshifted side. Dickey-Lockman neutral density well, only small snapshots have high-altitude consistent Reynolds Layer estimates. compute clumping correction C = /sqrt ~0.2 remarkably constant distance midplane time; can be used improve estimates mass electron observed surface brightness profiles edge-on