Star formation and stellar mass assembly in dark matter haloes: from giants to dwarfs

ABSTRACT Dwarf galaxies (M⋆ < 109 M⊙) are key drivers of mass assembly in high-mass galaxies, but relatively little is understood about the assembly of dwarf galaxies themselves. Using the NewHorizon cosmological simulation (∼40 pc spatial resolution), we investigate how mergers and fly-bys drive the mass assembly and structural evolution of around 1000 field and group dwarfs up to z = 0.5. We find that, while dwarf galaxies often exhibit disturbed morphologies (5 and 20 per cent are disturbed at z = 1 and z = 3 respectively), only a small proportion of the morphological disturbances seen in dwarf galaxies are driven by mergers at any redshift (for 109 M⊙, mergers drive under 20 per cent morphological disturbances). They are instead primarily the result of interactions that do not end in a merger (e.g. fly-bys). Given the large fraction of apparently morphologically disturbed dwarf galaxies which are not, in fact, merging, this finding is particularly important to future studies identifying dwarf mergers and post-mergers morphologically at intermediate and high redshifts. Dwarfs typically undergo one major and one minor merger between z = 5 and z = 0.5, accounting for 10 per cent of their total stellar mass. Mergers can also drive moderate star formation enhancements at lower redshifts (3 or 4 times at z = 1), but this accounts for only a few per cent of stellar mass in the dwarf regime given their infrequency. Non-merger interactions drive significantly smaller star formation enhancements (around two times), but their preponderance relative to mergers means they account for around 10 per cent of stellar mass formed in the dwarf regime.

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The Evolution of Dusty Star Formation and Stellar Mass Assembly in Clusters: Results from the IRAC 3.6, 4.5, 5.8, and 8.0 μm Cluster Luminosity Functions

The Astrophysical Journal ◽

10.1086/591542 ◽

2008 ◽

Vol 686 (2) ◽

pp. 966-994 ◽

Cited By ~ 62

Author(s):

Adam Muzzin ◽

Gillian Wilson ◽

Mark Lacy ◽

H. K. C. Yee ◽

S. A. Stanford

Keyword(s):

Star Formation ◽

Stellar Mass ◽

Luminosity Functions ◽

Mass Assembly

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The UV colours of high-redshift early-type galaxies: evidence for recent star formation and stellar mass assembly over the last 8 billion years

Monthly Notices of the Royal Astronomical Society ◽

10.1111/j.1365-2966.2008.13392.x ◽

2008 ◽

Vol 388 (1) ◽

pp. 67-79 ◽

Cited By ~ 69

Author(s):

S. Kaviraj ◽

S. Khochfar ◽

K. Schawinski ◽

S. K. Yi ◽

E. Gawiser ◽

...

Keyword(s):

Star Formation ◽

High Redshift ◽

Stellar Mass ◽

Early Type ◽

Mass Assembly

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Galaxy and mass assembly: luminosity and stellar mass functions in GAMA groups

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2889 ◽

2020 ◽

Vol 499 (1) ◽

pp. 631-652

Author(s):

J A Vázquez-Mata ◽

J Loveday ◽

S D Riggs ◽

I K Baldry ◽

L J M Davies ◽

...

Keyword(s):

Star Formation ◽

Formation Rate ◽

Mass Function ◽

Stellar Mass ◽

Dark Matter Halo ◽

Central Mass ◽

The Galaxy ◽

Star Formation In Galaxies ◽

Low Mass ◽

Mass Assembly

ABSTRACT How do galaxy properties (such as stellar mass, luminosity, star formation rate, and morphology) and their evolution depend on the mass of their host dark matter halo? Using the Galaxy and Mass Assembly group catalogue, we address this question by exploring the dependence on host halo mass of the luminosity function (LF) and stellar mass function (SMF) for grouped galaxies subdivided by colour, morphology, and central/satellite. We find that spheroidal galaxies in particular dominate the bright and massive ends of the LF and SMF, respectively. More massive haloes host more massive and more luminous central galaxies. The satellites LF and SMF, respectively, show a systematic brightening of characteristic magnitude, and increase in characteristic mass, with increasing halo mass. In contrast to some previous results, the faint-end and low-mass slopes show little systematic dependence on halo mass. Semi-analytic models and simulations show similar or enhanced dependence of central mass and luminosity on halo mass. Faint and low-mass simulated satellite galaxies are remarkably independent of halo mass, but the most massive satellites are more common in more massive groups. In the first investigation of low-redshift LF and SMF evolution in group environments, we find that the red/blue ratio of galaxies in groups has increased since redshift z ≈ 0.3 relative to the field population. This observation strongly suggests that quenching of star formation in galaxies as they are accreted into galaxy groups is a significant and ongoing process.

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Galaxy And Mass Assembly (GAMA): linking star formation histories and stellar mass growth

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stt1011 ◽

2013 ◽

Vol 434 (1) ◽

pp. 209-221 ◽

Cited By ~ 62

Author(s):

Amanda E. Bauer ◽

Andrew M. Hopkins ◽

Madusha Gunawardhana ◽

Edward N. Taylor ◽

Ivan Baldry ◽

...

Keyword(s):

Star Formation ◽

Stellar Mass ◽

Mass Growth ◽

Mass Assembly ◽

Star Formation Histories

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A contribution of star-forming clumps and accreting satellites to the mass assembly of z ∼ 2 galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2099 ◽

2019 ◽

Vol 489 (2) ◽

pp. 2792-2818 ◽

Cited By ~ 11

Author(s):

A Zanella ◽

E Le Floc’h ◽

C M Harrison ◽

E Daddi ◽

E Bernhard ◽

...

Keyword(s):

Star Formation ◽

Star Formation Rate ◽

Formation Rate ◽

Stellar Mass ◽

Mass Ratio ◽

Star Forming ◽

Spatially Resolved ◽

The Galaxy ◽

Mass Assembly

ABSTRACT We investigate the contribution of clumps and satellites to the galaxy mass assembly. We analysed spatially resolved HubbleSpace Telescope observations (imaging and slitless spectroscopy) of 53 star-forming galaxies at z ∼ 1–3. We created continuum and emission line maps and pinpointed residual ‘blobs’ detected after subtracting the galaxy disc. Those were separated into compact (unresolved) and extended (resolved) components. Extended components have sizes ∼2 kpc and comparable stellar mass and age as the galaxy discs, whereas the compact components are 1.5 dex less massive and 0.4 dex younger than the discs. Furthermore, the extended blobs are typically found at larger distances from the galaxy barycentre than the compact ones. Prompted by these observations and by the comparison with simulations, we suggest that compact blobs are in situ formed clumps, whereas the extended ones are accreting satellites. Clumps and satellites enclose, respectively, ∼20 per cent and ≲80 per cent of the galaxy stellar mass, ∼30 per cent and ∼20 per cent of its star formation rate. Considering the compact blobs, we statistically estimated that massive clumps (M⋆ ≳ 109 M⊙) have lifetimes of ∼650 Myr, and the less massive ones (108 < M⋆ < 109 M⊙) of ∼145 Myr. This supports simulations predicting long-lived clumps (lifetime ≳ 100 Myr). Finally, ≲30 per cent (13 per cent) of our sample galaxies are undergoing single (multiple) merger(s), they have a projected separation ≲10 kpc, and the typical mass ratio of our satellites is 1:5 (but ranges between 1:10 and 1:1), in agreement with literature results for close pair galaxies.

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A systematic search for galaxy proto-cluster cores at z ∼ 2

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320001933 ◽

2019 ◽

Vol 15 (S359) ◽

pp. 166-167

Author(s):

Makoto Ando ◽

Kazuhiro Shimasaku ◽

Rieko Momose

Keyword(s):

Dark Matter ◽

Galaxy Formation ◽

Clustering Analysis ◽

Mass Function ◽

Stellar Mass ◽

Dark Matter Halo ◽

Massive Galaxies ◽

The Galaxy ◽

Mass Assembly ◽

Cluster Cores

AbstractA proto-cluster core is the most massive dark matter halo (DMH) in a given proto-cluster. To reveal the galaxy formation in core regions, we search for proto-cluster cores at z ˜ 2 in ˜1.5deg2 of the COSMOS field. Using pairs of massive galaxies (log (M*/Mʘ) ≥ 11) as tracers of cores, we find 75 candidate cores. A clustering analysis and the extended Press-Schechter model show that their descendant mass at z = 0 is consistent with Fornax-like or Virgo-like clusters. Moreover, using the IllustrisTNG simulation, we confirm that pairs of massive galaxies are good tracers of DMHs massive enough to be regarded as proto-cluster cores. We then derive the stellar mass function and the quiescent fraction for member galaxies of the 75 candidate cores. We find that stellar mass assembly and quenching are accelerated as early as z ˜ 2 in proto-cluster cores.

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The cumulative star formation histories of dwarf galaxies with TNG50. I: environment-driven diversity and connection to quenching

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab2573 ◽

2021 ◽

Vol 508 (2) ◽

pp. 1652-1674 ◽

Cited By ~ 1

Author(s):

Gandhali D Joshi ◽

Annalisa Pillepich ◽

Dylan Nelson ◽

Elad Zinger ◽

Federico Marinacci ◽

...

Keyword(s):

Star Formation ◽

Dwarf Galaxies ◽

Control Sample ◽

Stellar Mass ◽

Key Factors ◽

Star Forming ◽

Theoretical Predictions ◽

Mass Assembly ◽

Star Formation Histories ◽

Vast Range

ABSTRACT We present the cumulative star formation histories (SFHs) of >15 000 dwarf galaxies ($M_{\rm *}=10^{7-10}\, {\rm M}_{\odot }$) simulated with the TNG50 run of the IllustrisTNG suite across a vast range of environments. The key factors that determine the dwarfs’ SFHs are their central/satellite status and stellar mass, with centrals and more massive dwarfs assembling their stellar mass at later times, on average, compared to satellites and lower mass dwarfs. Satellites (in hosts of mass $M_{\rm 200c, host}=10^{12-14.3}\, {\rm M}_{\odot }$) assembled 90 per cent of their stellar mass ${\sim}7.0_{-5.5}^{+3.3}$ Gyr ago, on average and within the 10th to 90th percentiles, while the centrals did so only ${\sim}1.0_{-0.5}^{+4.0}$ Gyr ago. TNG50 predicts a large diversity in SFHs, so that individual dwarfs can have significantly different cumulative SFHs compared to the stacked median SFHs. Satellite dwarfs with the highest stellar mass to host cluster mass ratios have the latest stellar mass assembly. Conversely, satellites at fixed stellar and host halo mass found closer to the cluster centre or accreted at earlier times show significantly earlier stellar mass assembly. These trends and the shapes of the SFHs themselves are a manifestation of the varying proportions within a given subsample of quenched versus star-forming galaxies, which exhibit markedly distinct SFH shapes. Finally, satellite dwarfs in the most massive hosts have higher SFRs at early times, well before accretion into their z = 0 host, compared to a control sample of centrals mass-matched at the time of accretion. This is the result of the satellites being preprocessed in smaller hosts prior to accretion. Our findings are useful theoretical predictions for comparison to future resolved stellar population observations.

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