Modeling the Lyman-$\alpha$ forest with Eulerian and SPH hydrodynamical methods

Abstract

We compare two state-of-the-art numerical codes to study the overall accuracy in modeling the intergalactic medium and reproducing Lyman-$\alpha$ forest observables for DESI and high-resolution data sets. The codes employ different approaches to solving both gravity and modeling the gas hydrodynamics. The first code, Nyx, solves the Poisson equation using the Particle-Mesh (PM) method and the Euler equations using a finite volume method. The second code, \CRKHACC, uses a Tree-PM method to solve for gravity, and an improved Lagrangian smoothed particle hydrodynamics (SPH) technique, where fluid elements are modeled with particles, to treat the intergalactic gas. We compare the convergence behavior of the codes in flux statistics as well as the degree to which the codes agree in the converged limit. We find good agreement overall with differences being less than observational uncertainties, and a particularly notable $\lesssim$1\% agreement in the 1D flux power spectrum. This agreement was achieved by applying a tessellation methodology for reconstructing the density in \CRKHACC instead of using an SPH kernel as is standard practice. We show that use of the SPH kernel can lead to significant and unnecessary biases in flux statistics; this is especially prominent at high redshifts, $z\sim 5$, as the Lyman-$\alpha$ forest mostly comes from lower-density regions which are intrinsically poorly sampled by SPH particles.

arXiv commentsubmitted to MNRAS

References in corpus (77)

• Seven-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• SDSS-III: Massive Spectroscopic Surveys of the Distant Universe, the Milky Way Galaxy, and Extra-Solar Planetary Systems
• The Baryon Oscillation Spectroscopic Survey of SDSS-III
• Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe
• The DESI Experiment Part I: Science,Targeting, and Survey Design
• X-shooter, the new wide band intermediate resolution spectrograph at the ESO Very Large Telescope
• Constraining Warm Dark Matter candidates including sterile neutrinos and light gravitinos with WMAP and the Lyman-alpha forest
• The SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Overview and Early Data
• Warm Dark Matter as a solution to the small scale crisis: new constraints from high redshift Lyman-alpha forest data
• Equation of State of the Photoionized Intergalactic Medium
• Improving convergence in smoothed particle hydrodynamics simulations without pairing instability
• Fundamental differences between SPH and grid methods
• The Santa Barbara cluster comparison project: a comparison of cosmological hydrodynamics solutions
• The Lyman Alpha Forest in the Spectra of QSOs
• First constraints on fuzzy dark matter from Lyman-$\alpha$ forest data and hydrodynamical simulations
• A General Class of Lagrangian Smoothed Particle Hydrodynamics Methods and Implications for Fluid Mixing Problems
• The Lyman-alpha Forest Power Spectrum from the Sloan Digital Sky Survey
• Measurement of BAO correlations at $z=2.3$ with SDSS DR12 \lya-Forests
• Recovery of the Power Spectrum of Mass Fluctuations from Observations of the Lyman-alpha Forest
• The Physics of the Intergalactic Medium
• The Evolution of the Intergalactic Medium
• The Observed Probability Distribution Function, Power Spectrum, and Correlation Function of the Transmitted Flux in the Lyman-alpha Forest
• The Coyote Universe I: Precision Determination of the Nonlinear Matter Power Spectrum
• New Measurements of the Ionizing Ultraviolet Background over 2 < z < 5 and Implications for Hydrogen Reionization
• Neutrino masses and cosmology with Lyman-alpha forest power spectrum
• Constraining the mass of light bosonic dark matter using SDSS Lyman-$\alpha$ forest
• Nyx: A Massively Parallel AMR Code for Computational Cosmology
• Measurement of Baryon Acoustic Oscillations in the Lyman-alpha Forest Fluctuations in BOSS Data Release 9
• Baryon acoustic oscillations from the complete SDSS-III Ly$\alpha$-quasar cross-correlation function at $z=2.4$
• Baryon acoustic oscillations at z = 2.34 from the correlations of Ly$\alpha$ absorption in eBOSS DR14
• Toward a Measurement of the Cosmological Geometry at z~2: Predicting Lyman-alpha Forest Correlation in Three Dimensions, and the Potential of Future Data Sets
• HACC: Simulating Sky Surveys on State-of-the-Art Supercomputing Architectures
• The Evolution of Optical Depth in the Ly-alpha Forest: Evidence Against Reionization at z~6
• The one-dimensional Ly-alpha forest power spectrum from BOSS
• Lyman-alpha Forests cool Warm Dark Matter
• How cold is cold dark matter? Small scales constraints from the flux power spectrum of the high-redshift Lyman-alpha forest
• The BACCO Simulation Project: Exploiting the full power of large-scale structure for cosmology
• The Lyman-$\alpha$ forest in optically-thin hydrodynamical simulations
• A Density Independent Formulation of Smoothed Particle Hydrodynamics
• Constraints on neutrino masses from Lyman-alpha forest power spectrum with BOSS and XQ-100
• New Constraints on IGM Thermal Evolution from the Lyα Forest Power Spectrum
• The one-dimensional power spectrum from the SDSS DR14 Ly$\alpha$ forests
• Constraints from Ly-$\alpha$ forests on non-thermal dark matter including resonantly-produced sterile neutrinos
• Constraints from the Lyman alpha forest power spectrum
• Possible evidence for an inverted temperature-density relation in the intergalactic medium from the flux distribution of the Lyman-alpha forest
• Revealing reionization with the thermal history of the intergalactic medium: new constraints from the Lyman-$\alpha$ flux power spectrum
• An improved measurement of the flux distribution of the Ly-alpha forest in QSO absorption spectra: the effect of continuum fitting, metal contamination and noise properties
• SPHS: Smoothed Particle Hydrodynamics with a higher order dissipation switch
• Constraint on neutrino masses from SDSS-III/BOSS Ly$\alpha$ forest and other cosmological probes
• An Exact Integration Scheme for Radiative Cooling in Hydrodynamical Simulations
• Self-Consistent Modeling of Reionization in Cosmological Hydrodynamical Simulations
• A consistent and robust measurement of the thermal state of the IGM at $2\le z\le 4$ from a large sample of Ly$\alpha$ forest spectra: Evidence for late and rapid HeII reionization
• CRKSPH - A Conservative Reproducing Kernel Smoothed Particle Hydrodynamics Scheme
• Cosmological and astrophysical constraints from the Lyman-alpha forest flux probability distribution function
• The Lyman-alpha forest power spectrum from the XQ-100 Legacy Survey
• nIFTy galaxy cluster simulations I: dark matter & non-radiative models
• Resolving the high redshift Lyman-alpha forest in smoothed particle hydrodynamics simulations
• IGM Constraints from the SDSS-III/BOSS DR9 Ly-alpha Forest Flux Probability Distribution Function
• The impact of feedback from galaxy formation on the Lyman-alpha transmitted flux
• A New Precision Measurement of the Small-Scale Line-of-Sight Power Spectrum of the Ly$\alpha$ Forest
• Moving mesh cosmology: properties of neutral hydrogen in absorption
• The Lyman alpha forest flux probability distribution at z>3
• Tightening Constraints from the Lyman Alpha Forest with the Flux Probability Distribution Function
• How to estimate the 3D power spectrum of the Lyman-$\alpha$ forest
• Inhomogeneous Reionization Models in Cosmological Hydrodynamical Simulations
• An emulator for the Lyman-$\alpha$ forest in beyond-$\Lambda$CDM cosmologies
• Numerical Simulations of the Lyman-alpha forest - A comparison of Gadget-2 and Enzo
• Sample variance and Lyman-alpha forest transmission statistics
• Optimal 1D Ly$\alpha$ Forest Power Spectrum Estimation -- II. KODIAQ, SQUAD & XQ-100
• Exploring the Thermal State of the Low-Density Intergalactic Medium at z=3 with an Ultra-High Signal-to-Noise QSO Spectrum
• The impact of AGN feedback on the 1D power spectra from the Ly$\alpha$ forest using the Horizon-AGN suite of simulations
• The Probability Distribution of the Lya transmitted flux from a sample of SDSS quasars
• Simulating intergalactic gas for DESI-like small scale Lymanα forest observations
• WEAVE-QSO: A Massive Intergalactic Medium Survey for the William Herschel Telescope
• Convergence of AMR and SPH simulations - I. Hydrodynamical resolution and convergence tests
• The Effect of Large-Scale Power on Simulated Spectra of the Lya forest
• Extracting the astrophysics of reionization from the Ly$\alpha$ forest power spectrum: a first forecast

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