Comparing Simulations and Observations of the Lyα Forest. I. Methodology

Cathy E. Petry, Chris D. Impey, Neal Katz, David H. Weinberg, Lars E. Hernquist
2002 Astrophysical Journal  
We describe techniques for comparing spectra extracted from cosmological simulations and observational data, using the same methodology to link Lyman-alpha properties derived from the simulations with properties derived from observational data. The eventual goal is to measure the coherence or clustering properties of Lyman-alpha absorbers using observations of quasar pairs and groups. We quantify the systematic underestimate in opacity that is inherent in the continuum fitting process of
more » ... d spectra over a range of resolution and signal-to-noise ratio. We present an automated process for detecting and selecting absorption features over the range of resolution and signal-to-noise of typical observational data on the Lyman-alpha "forest". Using these techniques, we detect coherence over transverse scales out to 500 h^-1_50 kpc in spectra extracted from a cosmological simulation at z = 2.
doi:10.1086/338033 fatcat:frh3nflrw5bmnjefzgm5vmlyzu