科研之友
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摘要
Outflows promote the escape of Lyman-alpha (Ly alpha) photons from dusty interstellar media. The process of radiative transfer through interstellar outflows is often modeled by a spherically symmetric, geometrically thin shell of neutral gas that scatters photons emitted by a central Ly alpha source. Despite its simplified geometry, this "shell model" has been surprisingly successful at reproducing observed Ly alpha line shapes. In this paper, we perform automated line fitting on a set of noisy simulated shell-model spectra in order to determine whether degeneracies exist between the different shell-model parameters. While there are some significant degeneracies, we find that most parameters are accurately recovered, especially the H I column density (N-H I) and outflow velocity (v(exp)). This work represents an important first step in determining how the shell-model parameters relate to the actual physical properties of Ly alpha sources. To aid further exploration of the parameter space, we have made our simulated model spectra available through an interactive online tool.
- 出版日期2015-10-20
