Imladris: a detailed and flexible model for galaxy simulations with individual stars

Abstract

Coupling stellar feedback to the evolution of individual stars, as opposed to averaging over the initial mass function (IMF), substantially improves the fidelity of galaxy formation simulations by capturing stochastic population effects. Existing treatments can typically only operate at a narrow mass resolution range, limiting their applicability. We present Imladris, a detailed model for star formation and stellar feedback with individual stars. At high resolution, each star can be represented by its own particle ("star-by-star"). At coarser resolution, star particles represent specific realisations of stellar populations sampled from the IMF. Both methods share a unified implementation of stellar feedback tied to the individually tracked stars, including supernovae, stellar winds and radiation. Imladris has been optimised for both computational efficiency and memory footprint. We demonstrate the model with idealised galaxy simulations ($M_{\mathrm{vir}}\sim 10^{10}-10^{11}{\mathrm{M}}_{\odot }$) spanning a baryonic mass resolution range of $2.5-1000{\mathrm{M}}_{\odot }$. Without re-calibration, the time-averaged star formation rate (SFR), galactic wind mass and energy loadings close to the disc are converged up to a resolution of $20{\mathrm{M}}_{\odot }$ within a factor of 1.1, 1.1 and 1.3, respectively, and 1.4, 1.6 and 2.5 up to $100{\mathrm{M}}_{\odot }$. Above this, SFRs become more bursty, while loading factors increase substantially. This is linked to resolution-dependent supernova clustering, which represents a fundamental barrier to convergence for any scheme attempting to model a self-consistent stellar feedback-regulated interstellar medium. Regardless, the ability to deploy the scheme across a wide range of resolutions (and to carry out in-depth resolution convergence studies) makes Imladris a powerful tool for numerical investigations of galaxy formation.

arXiv commentSubmitted to MNRAS. 36 pages, 15 figures

References in corpus (125)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• Array Programming with NumPy
• Astropy: A Community Python Package for Astronomy
• A Universal Density Profile from Hierarchical Clustering
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• On the variation of the Initial Mass Function
• The cosmological simulation code GADGET-2
• The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• E pur si muove: Galiliean-invariant cosmological hydrodynamical simulations on a moving mesh
• Cosmological SPH simulations: A hybrid multi-phase model for star formation
• Modeling feedback from stars and black holes in galaxy mergers
• Cosmological Hydrodynamics with Adaptive Mesh Refinement: a new high resolution code called RAMSES
• Simulating Galaxy Formation with the IllustrisTNG Model
• The EAGLE simulations of galaxy formation: calibration of subgrid physics and model variations
• Galaxies on FIRE (Feedback In Realistic Environments): Stellar Feedback Explains Cosmologically Inefficient Star Formation
• Physical Models of Galaxy Formation in a Cosmological Framework
• Radiative transfer in a clumpy universe: IV. New synthesis models of the cosmic UV/X-ray background
• The Neutral Atomic Phases of the ISM in the Galaxy
• Simba: Cosmological Simulations with Black Hole Growth and Feedback
• A model for cosmological simulations of galaxy formation physics
• Dancing in the dark: galactic properties trace spin swings along the cosmic web
• Enzo: An Adaptive Mesh Refinement Code for Astrophysics
• The physics driving the cosmic star formation history
• A Grid of NLTE Line-Blanketed Model Atmospheres of O-type Stars
• The chemical make-up of the Sun: A 2020 vision
• Theoretical Challenges in Galaxy Formation
• A Grid of NLTE Line-Blanketed Model Atmospheres of Early B-type Stars
• Star Clusters Across Cosmic Time
• Gas-to-Dust mass ratios in local galaxies over a 2 dex metallicity range
• The Faintest Dwarf Galaxies
• Galactic-Field IMFs of Massive Stars
• Photoelectric Emission from Interstellar Dust: Grain Charging and Gas Heating
• On the evolution of the HI column density distribution in cosmological simulations
• The Arepo public code release
• Momentum Injection by Supernovae in the Interstellar Medium
• Cosmic-ray ionization of molecular clouds
• Improving the convergence properties of the moving-mesh code AREPO
• Investigating the Cosmic-Ray Ionization Rate in the Galactic Diffuse Interstellar Medium through Observations of H3+
• Grackle: a Chemistry and Cooling Library for Astrophysics
• Enhanced cosmic-ray flux toward zeta Persei inferred from laboratory study of H3+ - e- recombination rate
• MUFASA: Galaxy Formation Simulations With Meshless Hydrodynamics
• The maximum stellar mass, star-cluster formation and composite stellar populations
• Protostellar Collapse with Various Metallicities
• H3+ in Diffuse Interstellar Clouds: a Tracer for the Cosmic-Ray Ionization Rate
• The relation between the most-massive star and its parental star cluster mass
• How To Model Supernovae in Simulations of Star and Galaxy Formation
• On the interplay between star formation and feedback in galaxy formation simulations
• Molecular Cloud Formation Behind Shock Waves
• Radiative feedback and the low efficiency of galaxy formation in low-mass haloes at high redshift
• SLUG - Stochastically Lighting Up Galaxies I: Methods and Validating Tests
• Implementation of feedback in SPH: towards concordance of methods
• Star formation, supernovae, iron, and alpha: consistent cosmic and Galactic histories
• NuGrid Stellar Data Set. II. Stellar Yields from H to Bi for Stellar Models with Mzams = 1 to 25Msun and Z = 0.0001 to 0.02
• Toward first-principle simulations of galaxy formation: I. How should we choose star formation criteria in high-resolution simulations of disk galaxies?
• Following the flow: tracer particles in astrophysical fluid simulations
• The Star Formation Law at Low Surface Density
• The Role of Stellar Feedback in the Dynamics of HII Regions
• The MillenniumTNG Project: The hydrodynamical full physics simulation and a first look at its galaxy clusters
• SLUG -- Stochastically Lighting Up Galaxies. III: A Suite of Tools for Simulated Photometry, Spectroscopy, and Bayesian Inference with Stochastic Stellar Populations
• Stochastic star formation and a (nearly) uniform stellar initial mass function
• Simulating the interstellar medium and stellar feedback on a moving mesh: Implementation and isolated galaxies
• FIRE-3: Updated Stellar Evolution Models, Yields, & Microphysics and Fitting Functions for Applications in Galaxy Simulations
• SPHGal: Smoothed Particle Hydrodynamics with improved accuracy for Galaxy simulations
• Star clusters near and far; tracing star formation across cosmic time
• Revisiting the Integrated Star Formation Law. Paper I: Non-Starbursting Galaxies
• JWST/NIRCam Probes Young Star Clusters in the Reionization Era Sunrise Arc
• Toward First-Principle Simulations of Galaxy Formation: II. Shock-Induced Starburst at a Collision Interface During the First Encounter of Interacting Galaxies
• Variable interstellar radiation fields in simulated dwarf galaxies: supernovae versus photoelectric heating
• The mmax-Mecl relation, the IMF and IGIMF: probabilistically sampled functions?
• Simulating an Isolated Dwarf Galaxy with Multi-Channel Feedback and Chemical Yields from Individual Stars
• SLUG - Stochastically Lighting Up Galaxies. II: Quantifying the Effects of Stochasticity on Star Formation Rate Indicators
• The GRIFFIN project -- Formation of star clusters with individual massive stars in a simulated dwarf galaxy starburst
• Supernova-driven winds in simulated dwarf galaxies
• Supernova feedback in numerical simulations of galaxy formation: separating physics from numerics
• On the Similarity between Cluster and Galactic Stellar Initial Mass Functions
• Cosmic-ray and X-ray Heating of Interstellar Clouds and Protoplanetary Disks
• Evolution of supernovae-driven superbubbles with conduction and cooling
• Efficient early stellar feedback can suppress galactic outflows by reducing supernova clustering
• DESPOTIC -- A New Software Library to Derive the Energetics and SPectra of Optically Thick Interstellar Clouds
• Efficiently Cooled Stellar Wind Bubbles in Turbulent Clouds II. Validation of Theory with Hydrodynamic Simulations
• N-body Integrators with Individual Time Steps from Hierarchical Splitting
• LYRA I: Simulating the multi-phase ISM of a dwarf galaxy with variable energy supernovae from individual stars
• Cosmic rays in molecular clouds probed by H${}_2$ rovibrational lines -- Perspectives for the James Webb Space Telescope
• Bonn Optimized Stellar Tracks (BoOST). Simulated Populations of Massive and Very Massive Stars for Astrophysical Applications
• A simple method to convert sink particles into stars
• Fervent: Chemistry-coupled, ionising and non-ionising radiative feedback in magnetohydrodynamical simulations
• Photochemistry and Heating/Cooling of the Multiphase Interstellar Medium with UV Radiative Transfer for Magnetohydrodynamic Simulations
• Stellar Feedback and Resolved Stellar IFU Spectroscopy in the nearby Spiral Galaxy NGC 300
• The role of galactic dynamics in shaping the physical properties of giant molecular clouds in Milky Way-like galaxies
• Chemical consequences of low star formation rates: stochastically sampling the IMF
• Computational issues in chemo-dynamical modelling of the formation and evolution of galaxies
• Hot phase generation by supernovae: resolution, chemistry and thermal conduction
• Roll of the Dice: A Stochastically Sampled IMF Alters the Stellar Content of Simulated Dwarf Galaxies
• SIRIUS project. I. Star formation models for star-by-star simulations of star clusters and galaxy formation
• How runaway stars boost galactic outflows
• Momentum feedback from marginally-resolved HII regions in isolated disc galaxies
• INFERNO: Galactic winds in dwarf galaxies with star-by-star simulations including runaway stars
• The sensitivity of stellar feedback to IMF averaging versus IMF sampling in galaxy formation simulations
• Sub-parsec resolution cosmological simulations of star-forming clumps at high redshift with feedback of individual stars
• Code Comparison in Galaxy Scale Simulations with Resolved Supernova Feedback: Lagrangian vs. Eulerian Methods
• RIGEL: Simulating dwarf galaxies at solar mass resolution with radiative transfer and feedback from individual massive stars
• Arkenstone I: A Novel Method for Robustly Capturing High Specific Energy Outflows In Cosmological Simulations
• Evolutionary tracks, ejecta, and ionizing photons from intermediate-mass to very massive stars with PARSEC
• Nucleosynthesis Constraints on the Explosion Mechanism for Type Ia Supernovae
• H2 self-shielding with non-LTE rovibrational populations: implications for cooling in protogalaxies
• Formation of star clusters and enrichment by massive stars in simulations of low-metallicity galaxies with a fully sampled initial stellar mass function
• Uncertainties in supernova input rates drive qualitative differences in simulations of galaxy evolution
• Anatomy of a z=6 Lyman-α emitter down to parsec scales: extreme UV slopes, metal-poor regions and possibly leaking star clusters
• Boosting galactic outflows with enhanced resolution
• On the effects of the Initial Mass Function on Galactic chemical enrichment
• Quantifying the energy balance between the turbulent ionised gas and young stars
• SIRIUS project II: a new tree-direct hybrid code for smoothed particle hydrodynamics/N-body simulations of star clusters
• SIEGE III: The formation of dense stellar clusters in sub-parsec resolution cosmological simulations with individual star feedback
• EDGE-INFERNO: Simulating every observable star in faint dwarf galaxies and their consequences for resolved-star photometric surveys
• The formation, evolution and disruption of star clusters with improved gravitational dynamics in simulated dwarf galaxies
• The Energy and Dynamics of Trapped Radiative Feedback with Stellar Winds
• Strength in numbers: A multiphase wind model with multiple cloud populations
• The impact of cosmic ray heating on the cooling of the low-metallicity interstellar medium
• The Noctua Suite of Simulations -- The Difficulty of Growing Massive Black Holes in Low-Mass Dwarf Galaxies
• The MandelZoom project I: modelling black hole accretion through an $\alpha$-disc in dwarf galaxies with a resolved interstellar medium
• Exploring effects of IMF sampling and SN feedback injection on star formation and metallicity in ultra-faint dwarf galaxies
• The MandelZoom project II: the impact of stellar feedback on black hole accretion through an $\alpha$-disc in dwarf galaxies with a resolved interstellar medium
• The Importance of Subtleties in the Scaling of the 'Terminal Momentum' For Galaxy Formation Simulations
• The Entangling of Supernova Feedback Impacts with Coarsening Simulation Resolution