2017/09/20 by Max Gronke, Max Grönke · 1 citation
Mathematics · Physics and Astronomy · #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Cosmic Phenomena #Concentric #Galaxies: Formation, Evolution, Phenomena #Galaxy #Gaussian #Geometry #Halo #Materials science #Mathematics #Optics #Physics #Quantum mechanics #Radiative transfer #Range (aeronautics) #Spectral index #Spectral line #Spectral shape analysis #astro-ph.GA
paper · pdf · doi:10.1051/0004-6361/201731791
published as A&A 608, A139 (2017) · 10 pages, 7 figures; data can be downloaded at http://bit.ly/a-spectra-of-MW
arxiv created 2017/09/20 · openalex publication_date 2017/09/25 · openalex created_date 2017/10/06 · arxiv updated 2017/12/20 · openalex updated_date 2026/08/05
We compare 237 Lyman-α (Lyα) spectra of the MUSE-Wide survey to a suite of radiative transfer simulations consisting of a central luminous source within a concentric, moving shell of neutral gas, and dust. This six parameter shell-model has been used numerously in previous studies, however, on significantly smaller data-sets. We find that the shell-model can reproduce the observed spectral shape very well – better than the also common “Gaussian-minus-Gaussian” model which we also fitted to the dataset. Specifically, we find that ~ 94% of the fits possess a goodness-of-fit value of p(χ2) > 0.1. The large number of spectra allows us to robustly characterize the shell-model parameter range, and consequently, the spectral shapes typical for realistic spectra. We find that the vast majority of the Lyα spectral shapes require an outflow and only ~ 5% are well-fitted through an inflowing shell. In addition, we find ~ 46% of the spectra to be consistent with a neutral hydrogen column density < 1017 cm-2 – suggestive of a non-negligible fraction of continuum leakers in the MUSE-Wide sample. Furthermore, we correlate the spectral against the Lyα halo properties against each other but do not find any strong correlation.