2009/06/16 by James S. Bolton, George D. Becker · 87 citations
Physics and Astronomy · #Astrophysics #Astrophysics and Cosmic Phenomena #Flux (metallurgy) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Intergalactic medium #Opacity #Optics #Physics #Radio Astronomy Observations and Technology #Redshift #Smoothed-particle hydrodynamics #Spectral density #Statistics #astro-ph.CO
paper · pdf · doi:10.1111/j.1745-3933.2009.00700.x
published in Monthly Notices of the Royal Astronomical Society Letters 398(1), L26-L30 (Oxford University Press) · 5 pages, 5 figures, 2 tables, accepted by MNRAS
arxiv created 2009/06/16 · openalex publication_date 2009/07/08 · arxiv updated 2015/05/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Abstract We use a large set of cosmological smoothed particle hydrodynamics (SPH) simulations to examine the effect of mass resolution and box size on synthetic Lyα forest spectra at 2 ≤z≤ 5. The mass resolution requirements for the convergence of the mean Lyα flux and flux power spectrum at z= 5 are significantly stricter than at lower redshift. This is because transmission in the high redshift Lyα forest is primarily due to underdense regions in the intergalactic medium (IGM), and these are less well resolved compared to the moderately overdense regions which dominate the Lyα forest opacity at z≃ 2–3. We further find that the gas density distribution in our simulations differs significantly from previous results in the literature at large overdensities (Δ > 10). We conclude that studies of the Lyα forest at z= 5 using SPH simulations require a gas particle mass of Mgas≤ 2 × 105h−1 M⊙, which is ≳8 times the value required at z= 2. A box size of at least 40 h−1 Mpc is preferable at all redshifts.