@miki

Efficient hydrodynamical simulations of the high-redshift intergalactic medium

, , , and . (2017)cite arxiv:1705.05374Comment: 21 pages, 14 figures, 3 tables. submitted to MNRAS.

Abstract

We present a post-processing tool for GADGET-2 simulations to model various observed properties of the Ly$\alpha$ forest at $2 z 4$ that enables an efficient parameter estimation. In particular, we model the thermal and ionization histories that are not computed self-consistently by default in GADGET-2. We capture the effect of pressure smoothing by running GADGET-2 at an elevated temperature floor and using an appropriate smoothing kernel. We validate our procedure by comparing different statistics derived from our method with those derived using self-consistent simulations with GADGET-3. These statistics are: line of sight density field power spectrum (PS), flux probability distribution function (PDF), flux PS, wavelet statistics, curvature statistics, HI column density ($N_HI$) distribution function, linewidth ($b$) distribution and $b$ versus $N_HI$ scatter. For the temperature floor of $10^4$ K and typical signal-to-noise of 25, the results agree well within $1\sigma$ level. Moreover for a given cosmology, we gain a factor of $N$ in computing time for modelling the intergalactic medium under $N 1$ different thermal histories. In addition, our method allows us to simulate the non-equilibrium evolution of thermal and ionization state of the gas and include heating due to non-standard sources like cosmic rays and high energy $\gamma$-rays from Blazars.

Description

[1705.05374] Efficient hydrodynamical simulations of the high-redshift intergalactic medium

Links and resources

Tags