Mergers, Starbursts, and Quenching in the Simba Simulation

Abstract

We use the Simba cosmological galaxy formation simulation to investigate the relationship between major mergers ($\le$ 4:1), starbursts, and galaxy quenching. Mergers are identified via sudden jumps in stellar mass $M_{\ast }$ well above that expected from in situ star formation, while quenching is defined as going from specific star formation rate sSFR$>t_H^{-1}$ to sSFR$<0.2t_H^{-1}$, where $t_H$ is the Hubble time. At $z\approx 0-3$, mergers show $\sim \times 2-3$ higher SFR than a mass-matched sample of star-forming galaxies, but globally represent $\le 1\%$ of the cosmic SF budget. At low masses, the increase in SFR in mergers is mostly attributed to an increase in the $H_2$ content, but for $M_{\ast }\ge 10^{10.5}{M}_{\odot }$ mergers also show an elevated star formation efficiency suggesting denser gas within merging galaxies. The merger rate for star-forming galaxies shows a rapid increase with redshift $\propto (1+z{)}^{3.5}$, but the quenching rate evolves much more slowly, $\propto (1+z{)}^{0.9}$; there are insufficient mergers to explain the quenching rate at $z\le 1.5$. Simba first quenches galaxies at $z\ge 3$, with a number density in good agreement with observations. The quenching timescales ${\tau }_q$ are strongly bimodal, with `slow' quenchings (${\tau }_q\sim 0.1t_H$) dominating overall, but `fast' quenchings (${\tau }_q\sim 0.01t_H$) dominating in $M_{\ast }\sim 10^{10}-10^{10.5}{M}_{\odot }$ galaxies, likely induced by Simba's jet-mode black hole feedback. The delay time distribution between mergers and quenching events suggests no physical connection to either fast or slow quenching. Hence, Simba predicts that major mergers induce starbursts, but are unrelated to quenching in either fast or slow mode.

18 pages, 13 figures

References in corpus (45)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• Mass and environment as drivers of galaxy evolution in SDSS and zCOSMOS and the origin of the Schechter function
• Star Formation in AEGIS Field Galaxies since z=1.1 : The Dominance of Gradually Declining Star Formation, and the Main Sequence of Star-Forming Galaxies
• A Cosmological Framework for the Co-Evolution of Quasars, Supermassive Black Holes, and Elliptical Galaxies: I. Galaxy Mergers & Quasar Activity
• A Highly Consistent Framework for the Evolution of the Star-Forming "Main Sequence" from z~0-6
• Heating Hot Atmospheres with Active Galactic Nuclei
• The Co-Evolution of Galaxies and Supermassive Black Holes: Insights from Surveys of the Contemporary Universe
• A Semi-Analytic Model for the Co-evolution of Galaxies, Black Holes, and Active Galactic Nuclei
• Simba: Cosmological Simulations with Black Hole Growth and Feedback
• Formation of Massive Galaxies at High Redshift: Cold Streams, Clumpy Disks and Compact Spheroids
• A unified model for AGN feedback in cosmological simulations of structure formation
• Massive molecular outflows and negative feedback in ULIRGs observed by Herschel-PACS
• How to Measure Galaxy Star Formation Histories II: Nonparametric Models
• Galaxy Pairs in the Sloan Digital Sky Survey I: Star Formation, AGN Fraction, and the Luminosity/Mass-Metallicity Relation
• The effect of galaxy mass ratio on merger--driven starbursts
• Grackle: a Chemistry and Cooling Library for Astrophysics
• Equal- and unequal-mass mergers of disk and elliptical galaxies with black holes
• Near infrared spectroscopy and star-formation histories of 3<z<4 quiescent galaxies
• Post-starburst galaxies: more than just an interesting curiosity
• A definitive merger-AGN connection at z~0 with CFIS: mergers have an excess of AGN and AGN hosts are more frequently disturbed
• HST WFC3/IR Observations of Active Galactic Nucleus Host Galaxies at z~2: Supermassive Black Holes Grow in Disk Galaxies
• Observational constraints on the merger history of galaxies since $z\approx 6$: Probabilistic galaxy pair counts in the CANDELS fields
• The evolution of star formation histories of quiescent galaxies
• The evolution of post-starburst galaxies from z=2 to z= 0.5
• The FABLE simulations: A feedback model for galaxies, groups and clusters
• Interacting galaxies on FIRE-2: The connection between enhanced star formation and interstellar gas content
• The role of mergers in driving morphological transformation over cosmic time
• High-Velocity Outflows Without AGN Feedback: Eddington-Limited Star Formation in Compact Massive Galaxies
• The main sequence of star forming galaxies I. The local relation and its bending
• Hot gas in massive halos drives both mass quenching and environment quenching
• Black Hole -- Galaxy Correlations in Simba
• The origins of post-starburst galaxies at z<0.05
• The structure of post-starburst galaxies at $0.5<z<2$: evidence for two distinct quenching routes at different epochs
• Painting galaxies into dark matter halos using machine learning
• Major mergers are not significant drivers of star formation or morphological transformation around the epoch of peak cosmic star formation
• A Comparison of Galaxy Merger History Observations and Predictions from Semi-Analytic Models
• E+A Galaxies with Blue Cores: Active Galaxies in Transition
• The redshift evolution of major merger triggering of luminous AGN: a slight enhancement at z$\sim$2
• Rejuvenated galaxies with very old bulges at the origin of the bending of the main sequence and of the "green valley"
• The diverse evolutionary pathways of post-starburst galaxies
• HI gas in rejuvenated radio galaxies: GMRT observations of the DDRG J1247+6723
• The Evolutionary Sequence of Post-Starburst Galaxies
• Compact star-forming galaxies preferentially quenched to become PSBs in $z<1$ clusters
• Timescales for Hi consumption and SFR depletion of satellite galaxies in groups

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• In pursuit of giants: II. Evolution of dusty quiescent galaxies over the last six billion years from the hCOSMOS survey
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• The NEWFIRM HETDEX Survey: Photometric Catalog and a Conservative Sample of Massive Quiescent Galaxies at z=3-5 over 17.5 deg^2 in the SHELA Field
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