The formation of low metallicity globular clusters in dwarf galaxy mergers

Abstract

We present a hydro-dynamical simulation at sub-parsec and few solar mass resolution of a merger between two gas-rich dwarf galaxies. Our simulation includes a detailed model for the multi-phase interstellar medium (ISM) and is able to follow the entire formation history of spatially resolved star clusters, including feedback from individual massive stars. Shortly after the merger we find a population of $\sim 900$ stellar clusters with masses above $10^{2.5}{\mathrm{M}}_{\odot }$ and a cluster mass function (CMF), which is well fitted with a power-law with a slope of $\alpha =-1.70\pm 0.08$. We describe here in detail the formation of the three most massive clusters (M${}_{\ast }\gtrsim 10^5$ M${}_{\odot }$), which populate the high-mass end of the CMF. The simulated clusters form rapidly on a timescale of $6$-$8$ Myr in converging flows of dense gas. The embedded merger phase has extremely high star formation rate surface densities of ${\Sigma }_{\mathrm{SFR}}>10{\mathrm{M}}_{\odot }{\mathrm{yr}}^{-1}{\mathrm{kpc}}^{-2}$ and thermal gas pressures in excess of $P_{\mathrm{th}}\sim 10^7{\mathrm{k}}_{\mathrm{B}}(\mathrm{K}{\mathrm{cm}}^{-3}{)}^{-1}$. The formation process is terminated by rapid gas expulsion driven by the first generation of supernovae, after which the cluster centers relax and both their structure and kinematics become indistinguishable from observed local globular clusters. The simulation presented here provides a general model for the formation of metal-poor globular clusters in chemically unevolved starbursting environments of low-mass dwarf galaxies, which are common at high redshifts.

Accepted for publication in ApJL. 8 pages, 5 figures

References in corpus (7)

• The effect of photo-ionization on the cooling rates of enriched, astrophysical plasmas
• Mass loss from hot massive stars
• Modelling discontinuities and Kelvin-Helmholtz instabilities in SPH
• Simulating the formation of molecular clouds. I. Slow formation by gravitational collapse from static initial conditions
• Paving the way for the JWST: witnessing globular cluster formation at z>3
• A parsec-resolution simulation of the Antennae galaxies: Formation of star clusters during the merger
• High-resolution simulations of galaxy mergers: Resolving globular cluster formation

Cited by in corpus (52)

• STARFORGE: Toward a comprehensive numerical model of star cluster formation and feedback
• The GRIFFIN project -- Formation of star clusters with individual massive stars in a simulated dwarf galaxy starburst
• Intermediate Mass Black Hole Formation in compact Young Massive Star Clusters
• The Science of the Einstein Telescope
• Metallicity dependence of the H/H${}_2$ and C${}^{+}$/C/CO distributions in a resolved self-regulating interstellar medium
• Black hole mergers in compact star clusters and massive black hole formation beyond the mass-gap
• Introducing EMP-Pathfinder: modelling the simultaneous formation and evolution of stellar clusters in their host galaxies
• The merger-starburst connection across cosmic times
• On the origin of surprisingly cold gas discs in galaxies at high redshift
• How runaway stars boost galactic outflows
• INFERNO: Galactic winds in dwarf galaxies with star-by-star simulations including runaway stars
• Great Balls of FIRE I: The formation of star clusters across cosmic time in a Milky Way-mass galaxy
• Dark Matter Deficient Galaxies And Their Member Star Clusters Form Simultaneously During High-velocity Galaxy Collisions In 1.25 pc Resolution Simulations
• The challenge of simulating the star cluster population of dwarf galaxies with resolved interstellar medium
• Star formation histories of the LEGUS dwarf galaxies (III): the non-bursty nature of 23 star forming dwarf galaxies
• 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
• Massive star cluster formation I. High star formation efficiency while resolving feedback of individual stars
• The formation of massive stellar clusters in converging galactic flows with photoionisation
• Constraining the formation of NGC1052-DF2 from its unusual globular cluster population
• Formation of star clusters and enrichment by massive stars in simulations of low-metallicity galaxies with a fully sampled initial stellar mass function
• Structure and rotation of young massive star clusters in a simulated dwarf starburst
• The role of collision speed, cloud density, and turbulence in the formation of young massive clusters via cloud-cloud collisions
• Globular cluster numbers in dark matter haloes in a dual formation scenario: an empirical model within EMERGE
• Spectral properties and detectability of supermassive stars in protoglobular clusters at high redshift
• The formation of clusters and OB associations in different density spiral arm environments
• Star clusters forming in a low metallicity starburst -- rapid self-enrichment by (very) massive stars
• The origin of the [CII]-deficit in a simulated dwarf galaxies starburst
• Modeling globular clusters in the TNG50 simulation: predictions from dwarfs to giants
• Rapid formation of a very massive star >50000 $M_{\odot }$ and subsequently an IMBH from runaway collisions. Direct N-body and Monte Carlo simulations of dense star clusters
• Testing Feedback from Star Clusters in Simulations of the Milky Way Formation
• Mechanical feedback from stellar winds with an application to galaxy formation at high redshift
• Revealing the formation mechanism of the shell galaxy NGC474 with MUSE
• The Formation of Binary Star Clusters in the Milky Way and Large Magellanic Cloud
• The Column Densities of Molecular Gas across Cosmic Time: Bridging Observations and Simulations
• The spatial distribution of globular clusters in dwarf spheroidal galaxies and the timing problem
• A Tale of 3 Dwarfs: No Extreme Cluster Formation in Extreme Star-Forming Galaxies
• Great Balls of FIRE III: Modeling Black Hole Mergers from Massive Star Clusters in Simulations of Galaxies
• Galaxy archaeology for wet mergers: Globular cluster age distributions in the Milky Way and nearby galaxies
• A panchromatic view of star cluster formation in a simulated dwarf galaxy starburst
• The formation of globular clusters with top-heavy initial mass functions
• Impact of Radiation Feedback on the Formation of Globular Cluster Candidates during Cloud-Cloud Collisions
• Globular cluster ages and their relation to high-redshift stellar cluster formation times from different globular cluster models
• Influence of mergers on LyC escape of high redshift galaxies
• Great Balls of FIRE IV. The contribution of massive star clusters to the astrophysical population of merging binary black holes
• The formation and disruption of globular cluster populations in simulations of present-day $L^{\ast }$ galaxies with controlled assembly histories
• Spatial segregation of massive clusters in dwarf galaxies
• Feedback from intermediate mass black holes on dwarf galaxy morphology at z=2
• Chemical enrichment by collapsars as the origin of the unusually high [Ba/Fe] in a massive star cluster of the dwarf galaxy NGC 1569
• The Star Formation Factory revisited I. The impact of metallicity on collapsing star-forming clouds
• RIGEL: Feedback-regulated cloud-scale star formation efficiency in a simulated dwarf galaxy merger
• Infrared photometry and CaT spectroscopy of the most metal-poor in-situ globular cluster VVV-CL001