Cosmological simulations of intergalactic medium enrichment from galactic outflows

By B. Oppenheimer, R. Dav'e. 2006

495 citations recorded by the source corpus.

We investigate models of self-consistent chemical enrichment of the intergalactic medium (IGM) from z = 6.0 → 1.5, based on hydrodynamic simulations of structure formation that explicitly incorporate outflows from star-forming galaxies. Our main result is that outflow parametrizations derived from observations of local starburst galaxies, in particular momentum-driven wind scenarios, provide the best agreement with observations of C iv absorption at z ∼ 2-5. Such models sufficiently enrich the high-z IGM to produce a global mass density of Civ absorbers that is relatively invariant from z = 5.5 → 1.5, in agreement with observations. This occurs despite continual IGM enrichment causing an increase in volume-averaged metallicity by ∼ x 5-10 over this redshift range, because energy input accompanying the enriching outflows causes a drop in the global ionization fraction of C iv. Comparisons to observed C IV column density and linewidth distributions and C IV-based pixel optical depth ratios provide significant constraints on wind models. Our best-fitting outflow models show mean IGM temperatures only slightly above our no-outflow case, metal filling factors of just a few per cent with volume-weighted metallicities around 10 -3 at z ∼ 3, significant amounts of collisionally ionized C iv absorption and a metallicity-density relationship that rises rapidly at low overdensities and flattens at higher ones. In general, we find that outflow speeds must be high enough to enrich the low-density IGM at early times but low enough not to overheat it, and concurrently must significantly suppress early star formation while still producing enough early metals. It is therefore non-trivial that locally calibrated momentum-driven wind scenarios naturally yield the desired strength and evolution of outflows, and suggest that such models represent a significant step towards understanding the impact of galactic outflows on galaxies and the IGM across cosmic time.

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/f51033a1dbe771be0125f2201579277b204600e5

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Citations in the corpus

Galaxy Evolution in Cosmological Simulations with Outflows II: Metallicities and Gas Fractions (2011, methodology): “…are among the most successful at matching a wide range of data on galaxies (e.g. Davé, Finlator, & Oppenheimer 2006; Finlator & Davé 2008; Oppenheimer et al. 2010) and the IGM (e.g. Oppenheimer & Davé 2006, 2008, 2009; Oppenheimer, Davé, & Finlator 2009), although notable discrepancies remain.”
The MassiveBlack-II simulation: The evolution of haloes and galaxies to z ~ 0 (2014, methodology): “A variable wind model based on the galaxy velocity dispersion (Oppenheimer & Davé 2006; Davé et al. 2011; Vogelsberger et al. 2013; Torrey et al. 2014) has been shown to flatten the GSMF at smaller masses to better reproduce observational constraints at z = 0.”
Stellar Feedback in Galaxies and the Origin of Galaxy-scale Winds (2011, background): “Oppenheimer & Davé (2006) and Oppenheimer et al. (2010) find that an average scaling Ṁwind/Ṁ∗ ∝ V −1c produces reasonably good agreement with the observed mass functions at different redshifts,1 with a normalization such that a Small Magellanic Cloud (SMC) mass dwarf has a mass loading…”
A model for cosmological simulations of galaxy formation physics: multi-epoch validation (2013, background): “…Icke 1997; Thacker & Couchman 2000; Kay et al. 2002; Kawata & Gibson 2003; Sommer-Larsen et al. 2003; Springel & Hernquist 2003a; Brook et al. 2004; Oppenheimer & Davé 2006; Stinson et al. 2006; Dubois & Teyssier 2008; Dalla Vecchia & Schaye 2008; Okamoto et al. 2010; Piontek & Steinmetz 2011;…”
The enrichment of the intergalactic medium with adiabatic feedback – I. Metal cooling and metal diffusion (2009, methodology): “At z=0, about 40% of the mass is in WHIM, consistent previous simulations with different methods (Cen & Ostriker 2006; Oppenheimer & Davé 2006).”
The Evolution of the Intergalactic Medium (2015, background): “…a cosmological volume that attempt to capture galaxy formation.13 These simulations adopt “feedback” recipes for how star formation (and sometimes quasar activity) expel gas (Aguirre et al. 2001a,b; Tescari et al. 2011; Oppenheimer & Davé 2006; Wiersma et al. 2010; Wiersma, Schaye & Theuns 2011).”
Simulating galactic outflows with thermal supernova feedback (2012, background): “…injecting the energy in kinetic form (e.g. Navarro & White 1993; Mihos & Hernquist 1994; Kawata 2001; Kay et al. 2002; Springel & Hernquist 2003; Oppenheimer & Davé 2006; Dalla Vecchia & Schaye 2008; Dubois & Teyssier 2008; Hopkins, Quataert, & Murray 2012), suppressing radiative cooling by…”
The observed ionization rate of the intergalactic medium and the ionizing emissivity at z≥ 5: evidence for a photon-starved and extended epoch of reionization (2007, background): “…structure formation (Cen 1992; Miralda-Escudé et al. 1996; Theuns et al. 1998; Jena et al. 2005) and provide the ionization corrections needed to infer the abundances of heavy elements in the IGM from metal ion absorption lines (Giroux & Shull 1997; Aguirre et al. 2005; Oppenheimer & Davé 2006).”
THE SINS/zC-SINF SURVEY of z ∼ 2 GALAXY KINEMATICS: OUTFLOW PROPERTIES (2012, background): “For the SFGs in the ‘wind regime’ (ΣSFR > 1 M⊙yr −1kpc−2) we do not see any significant variation of Fbroad/Fnarrow as a function of vc, which is expected theoretically for momentum driven winds (η ∝ v−1c , Murray et al. 2005; Oppenheimer & Davé 2006, 2008; Hopkins et al. 2012).”
How Stellar Feedback Simultaneously Regulates Star Formation and Drives Outflows (2015, background): “Such treatments of outflows are useful because they enable these simulations to satisfy a wide variety of observational constraints (e.g.Oppenheimer & Davé 2006, 2008; Oppenheimer et al. 2010, 2012; Davé et al. 2011a,b, 2013; Puchwein & Springel 2013; Vogelsberger et al. 2014; Schaye et al. 2015;…”
Mass, metal, and energy feedback in cosmological simulations (2007, methodology): “Galactic outflows appear to be the only viable method to enrich the IGM to the observed levels as simulations show that tidal stripping only is not sufficient (Aguirre et al. 2001; Oppenheimer & Davé 2006, hereafter OD06).”
Effects of supernova feedback on the formation of galaxy discs (2008, background): “…2002; Abadi et al. 2003; Marri & White 2003; Sommer-Larsen, Götz & Portinari 2003; Springel & Hernquist 2003; Brook et al. 2004; Okamoto et al. 2005; Oppenheimer & Davé 2006; Stinson et al. 2006; Governato et al. 2007; Dalla Vecchia & Schaye 2008; Dubois & Teyssier 2008; Finlator & Davé 2008).”
The physics driving the cosmic star formation history (2009, methodology): “Oppenheimer & Davé (2006) implemented several versions of momentum-driven winds into cosmological simulations of the chemical enrichment of the IGM and found good agreement with observations of C IV absorption.”
Physical Models of Galaxy Formation in a Cosmological Framework (2014, background): “Oppenheimer & Davé (2006) showed that adopting scalings motivated by analytic “momentum-driven” wind models (Murray et al. 2005) produced better agreement with many galaxy and IGM properties including the galaxy mass-metallicity relation, the enrichment history of the IGM, and the galaxy stellar…”
A fundamental problem in our understanding of low-mass galaxy evolution (2012, methodology): “The vzw model was initially tuned to match CIV absorption in quasar absorption line spectra at z = 2− 5 (Oppenheimer & Davé 2006).”
THEORETICAL EVOLUTION OF OPTICAL STRONG LINES ACROSS COSMIC TIME (2013, background): “This code incorporates gas cooling and heating processes, including the effects of metal line cooling 3 (Oppenheimer & Davé 2006).”
Galaxies in a simulated ΛCDM universe – II. Observable properties and constraints on feedback (2009, background): “Journal compilation C© 2009 RAS nloaded from https://academ ic.oup.com /m nras/article-abstract/396/4/2332/1030564 by guest on 11 D ecem ber 2018 the IGM metal distribution rely on scaling relations appropriate for momentum-driven winds (Murray, Quataert & Thompson 2005; Oppenheimer & Davé 2006).”
Rotational support of giant clumps in high-z disc galaxies (2011, unknown): “This is the case in the simulations of Genel et al. (2010), where disruptive outflows are assumed by implementing an enhanced-outflow version of the phenomenological model of Oppenheimer & Davé (2006, 2008).”
Hierarchical formation of bulgeless galaxies – II. Redistribution of angular momentum via galactic fountains (2011, background): “The large scale ejection of low angular momentum gas meshes well with the need to enrich the IGM (Mac Low & Ferrara 1999; Oppenheimer & Davé 2006; Shen et al. 2010), and also with the observed low baryonic mass fraction of low mass galaxies (e.g. Klypin et al. 1999; Mandelbaum et al. 2006; Koposov…”
THE MASS–METALLICITY RELATION WITH THE DIRECT METHOD ON STACKED SPECTRA OF SDSS GALAXIES (2012, methodology): “However, recent simulations by Oppenheimer & Davé (2006), Finlator & Davé (2008), and Davé et al. (2011a, 2011b) show that winds characterized by a constant velocity and constant mass-loading parameter (mass outflow rate divided by SFR; their cw simulations), which were intended to represent…”