Multi-scale initial conditions for cosmological simulations

By Oliver Hahn, Tom Abel. 2011

591 citations recorded by the source corpus.

We discuss a new algorithm to generate multi-scale initial conditions with multiple levels of refinements for cosmological 'zoom-in' simulations. The method uses an adaptive convolution of Gaussian white noise with a real-space transfer function kernel together with an adaptive multi-grid Poisson solver to generate displacements and velocities following first- (1LPT) or second-order Lagrangian perturbation theory (2LPT). The new algorithm achieves rms relative errors of the order of 10{sup -4} for displacements and velocities in the refinement region and thus improves in terms of errors by about two orders of magnitude over previous approaches. In addition, errors are localized at coarse-fine boundaries and do not suffer from Fourier-space-induced interference ringing. An optional hybrid multi-grid and Fast Fourier Transform (FFT) based scheme is introduced which has identical Fourier-space behaviour as traditional approaches. Using a suite of re-simulations of a galaxy cluster halo our real-space-based approach is found to reproduce correlation functions, density profiles, key halo properties and subhalo abundances with per cent level accuracy. Finally, we generalize our approach for two-component baryon and dark-matter simulations and demonstrate that the power spectrum evolution is in excellent agreement with linear perturbation theory. For initial baryon density fields, it is suggested to use the local Lagrangian approximation in order to generate a density field for mesh-based codes that is consistent with the Lagrangian perturbation theory instead of the current practice of using the Eulerian linearly scaled densities.

Subfields: Astronomy and Astrophysics, Instrumentation, Statistical and Nonlinear Physics

View Paper: https://www.semanticscholar.org/paper/2580acf11324ea8cad96998d558a28b3ae3b36c9

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Citations in the corpus

ELVIS: Exploring the Local Volume in Simulations (2013, methodology): “We also thank Volker Springel for making Gadget-2 publicly available and for providing a version of Gadget-3 for our use, Peter Behroozi for making Rockstar and consistent-trees publicly available, and Oliver Hahn for making MUSIC publicly available.”
The origin and evolution of the galaxy mass–metallicity relation (2015, methodology): “We use the multi-scale “zoom-in” initial conditions generated with the MUSIC code (Hahn & Abel 2011), using second-order Lagrangian perturbation theory.”
Tracing the dark matter sheet in phase space (2011, methodology): “The initial conditions for these single-mass-resolution simulations were generated with the Music code (Hahn & Abel 2011) keeping large-scale phases identical with changing mass and spatial resolution.”
MUFASA: Galaxy Formation Simulations With Meshless Hydrodynamics (2016, methodology): “We generate initial conditions with these parameters using Music (Hahn & Abel 2011).”
EMERGE – an empirical model for the formation of galaxies since z ∼ 10 (2017, methodology): “The initial conditions for both simulations were generated with the Music code (Hahn & Abel 2011) using a power spectrum computed with the CAMB code (Lewis, Challinor & Lasenby 2000).”
Fluctuating feedback-regulated escape fraction of ionizing radiation in low-mass, high-redshift galaxies (2017, methodology): “The initial conditions for the resimulations are produced using the Music2 code (Hahn & Abel 2011).”
Matter power spectrum and the challenge of percent accuracy (2015, methodology): “The initial conditions are generated with MUSIC (Hahn & Abel 2011), using both the ZA and 2LPT approach at different starting redshifts.”
The upper bound on the lowest mass halo (2016, background): “The zoom-in strategy broadly follows Oñorbe et al. (2014) and initial conditions are generated with music (Hahn & Abel 2011).”
Sweating the small stuff: simulating dwarf galaxies, ultra-faint dwarf galaxies, and their own tiny satellites (2015, methodology): “1 The initial conditions were generated using MUSIC (Hahn & Abel 2011), and selected from a cosmological box 1 Note that Dwarf 2Early and UFD 1 were also previously presented in Hopkins et al. (2014) as m9 and m10 respectively. run at low resolution to z = 0.”
FIRE in the field: Simulating the threshold of galaxy formation (2016, methodology): “The halos span a representative range of concentrations (and therefore, formation times; e.g. Navarro et al. 1997; Wechsler et al. 2002) for their mass. Initial conditions are generated with MUSIC (Hahn & Abel 2011).”
CONTRASTING GALAXY FORMATION FROM QUANTUM WAVE DARK MATTER, ψDM, WITH ΛCDM, USING PLANCK AND HUBBLE DATA (2015, methodology): “We adopt the CAMB package (Lewis et al. 2000) to generate the CDM transfer function, and construct initial conditions for simulations using the MUSIC code (Hahn & Abel 2011).”
Core formation in dwarf haloes with self-interacting dark matter: no fine-tuning necessary (2014, methodology): “Initial conditions were generated with MUSIC (Hahn & Abel, 2011) at z = 125 using cosmological parameters derived from the Wilkinson Microwave Anisotropy Probe-7 year data (Komatsu et al., 2011): h = 0.71, Ωm = 0.266, ΩΛ = 0.734, ns = 0.963, and σ8 = 0.801.”
A volumetric deep Convolutional Neural Network for simulation of dark matter halo catalogues (2018, background): “When combined with a multi-scale initial conditions generator (e.g. Hahn & Abel (2011)), holding the full simulation in memory at once can also be eliminated, and a large volume of the universe can be simulated on any modest machine.”
Scaling relations for galaxy clusters in the Millennium-XXL simulation (2012, methodology): “The Fourier transform of this field was then used to set the amplitudes of all of the modes needed to make the initial conditions (Salmon 1996; Bertschinger 2001; Hahn & Abel 2011).”
The warm dark matter halo mass function below the cut-off scale (2013, methodology): “Using the WDM primordial power spectrum discussed above and the MUSIC code (Hahn & Abel 2011), we then create the initial particle configuration at z = 63 for our numerical experiments.”
ETHOS - an effective theory of structure formation: dark matter physics as a possible explanation of the small-scale CDM problems (2015, methodology): “All initial conditions were generated with the MUSIC code (Hahn & Abel 2011).”
Cosmological simulations with self-interacting dark matter – II. Halo shapes versus observations (2012, unknown): “The initial conditions were generated using the MUSIC code at z = 250 (Hahn & Abel 2011) with a year seven WMAP cosmology (Komatsu et al. 2011): h = 0.71, Ωm = 0.266, ΩΛ = 0.734, Ωb = 0.0449, ns = 0.963, σ8 = 0.801.”