A Comparison of Cosmological Codes: Properties of Thermal Gas and Shock Waves in Large Scale Structures

Astronomy and Astrophysics – Astrophysics – Cosmology and Extragalactic Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

30 pages, 24 figures. Version accepted by MNRAS. Only minor changes and updated references list compared to the first submitte

Scientific paper

[...] We present results for the statistics of thermal gas and the shock wave properties for a large volume simulated with three different cosmological numerical codes: the Eulerian total variations diminishing code TVD, the Eulerian piecewise parabolic method-based code ENZO, and the Lagrangian smoothed-particle hydrodynamics code GADGET. Starting from a shared set of initial conditions, we present convergence tests for a cosmological volume of side-length 100 Mpc/h, studying in detail the morphological and statistical properties of the thermal gas as a function of mass and spatial resolution in all codes. By applying shock finding methods to each code, we measure the statistics of shock waves and the related cosmic ray acceleration efficiencies, within the sample of simulations and for the results of the different approaches. We discuss the regimes of uncertainties and disagreement among codes, with a particular focus on the results at the scale of galaxy clusters. Even if the bulk of thermal and shock properties are reasonably in agreement among the three codes, yet some significant differences exist (especially between Eulerian methods and smoothed particle hydrodynamics). In particular, we report: a) differences of huge factors (10-100) in the values of average gas density, temperature, entropy, Mach number and shock thermal energy flux in the most rarefied regions of the simulations between grid and SPH methods; b) the hint of an entropy core inside clusters simulated in grid codes; c) significantly different phase diagrams of shocked cells in grid codes compared to SPH; d) sizable differences in the morphologies of accretion shocks between grid and SPH methods.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

A Comparison of Cosmological Codes: Properties of Thermal Gas and Shock Waves in Large Scale Structures does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with A Comparison of Cosmological Codes: Properties of Thermal Gas and Shock Waves in Large Scale Structures, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A Comparison of Cosmological Codes: Properties of Thermal Gas and Shock Waves in Large Scale Structures will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-413263

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.