Do Intermediate-Age Star Clusters Have Extended Star Formation Histories?

In an effort to better understand how the properties of star formation in starburst galaxies depend on various environmental parameters, I present a comparison between two well-known WR galaxies: the interacting galaxy system NGC 1741 in the Hickson Compact Group 31, and the dwarf galaxy He2-10. The high spatial resolution of HST has allowed identification of a large number of starburst knots, or ‘super star clusters’ in these WR galaxies. Broad-band photometry and the latest stellar synthesis models are used to estimate the ages and masses of the super star clusters. The properties of the clusters are then used to compare and contrast the overall star-formation histories in the two WR galaxies.

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Connections between MWG Star Clusters and Dwarf Galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921314005742 ◽

2012 ◽

Vol 10 (H16) ◽

pp. 275-277

Author(s):

Kim A. Venn

Keyword(s):

Star Formation ◽

Globular Clusters ◽

Dwarf Galaxies ◽

Star Clusters ◽

Theoretical Models ◽

Stellar Populations ◽

Observational Evidence ◽

Paradigm Shifts ◽

The Past ◽

Star Formation Histories

It seems that in the past decade, there have been two paradigm shifts regarding star clusters. Firstly, the observational evidence for multiple stellar populations requires more extended and often complex star formation histories in star clusters. Secondly, theoretical models that form globular clusters in dwarf galaxies that are accreted at very early epochs (z > 5) are able to reproduce the age-metallicity relations observed. For the accretion scenario to be viable, globular clusters should also resemble the chemistry of at least some dwarf galaxies.

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Is the escape velocity in star clusters linked to extended star formation histories? Using NGC 7252: W3 as a test case

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stv2977 ◽

2016 ◽

Vol 457 (1) ◽

pp. 809-821 ◽

Cited By ~ 26

Author(s):

I. Cabrera-Ziri ◽

N. Bastian ◽

M. Hilker ◽

B. Davies ◽

F. Schweizer ◽

...

Keyword(s):

Star Formation ◽

Star Clusters ◽

Test Case ◽

Escape Velocity ◽

Star Formation Histories

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Stellar populations and star formation histories of the nuclear star clusters in six nearby galaxies★

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/sty1985 ◽

2018 ◽

Vol 480 (2) ◽

pp. 1973-1998 ◽

Cited By ~ 26

Author(s):

Nikolay Kacharov ◽

Nadine Neumayer ◽

Anil C Seth ◽

Michele Cappellari ◽

Richard McDermid ◽

...

Keyword(s):

Star Formation ◽

Star Clusters ◽

Stellar Populations ◽

Nearby Galaxies ◽

Star Formation Histories

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The effects of star formation history in the SFR–M* relation of H ii galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3333 ◽

2020 ◽

Vol 500 (3) ◽

pp. 3240-3253

Author(s):

Amanda R Lopes ◽

Eduardo Telles ◽

Jorge Melnick

Keyword(s):

Star Formation ◽

Spectral Energy Distribution ◽

Formation Rate ◽

Star Formation History ◽

Spectral Energy ◽

Distribution Fitting ◽

Good Tool ◽

Star Forming ◽

Additional Information ◽

Star Formation Histories

ABSTRACT We discuss the implications of assuming different star formation histories (SFH) in the relation between star formation rate (SFR) and mass derived by the spectral energy distribution fitting (SED). Our analysis focuses on a sample of H ii galaxies, dwarf starburst galaxies spectroscopically selected through their strong narrow emission lines in SDSS DR13 at z < 0.4, cross-matched with photometric catalogues from GALEX, SDSS, UKIDSS, and WISE. We modelled and fitted the SEDs with the code CIGALE adopting different descriptions of SFH. By adding information from different independent studies, we find that H ii galaxies are best described by episodic SFHs including an old (10 Gyr), an intermediate age (100−1000 Myr) and a recent population with ages < 10 Myr. H ii galaxies agree with the SFR−M* relation from local star-forming galaxies, and only lie above such relation when the current SFR is adopted as opposed to the average over the entire SFH. The SFR−M* demonstrated not to be a good tool to provide additional information about the SFH of H ii galaxies, as different SFH present a similar behaviour with a spread of <0.1 dex.

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Galaxy and mass assembly (GAMA): the inferred mass–metallicity relation from z = 0 to 3.5 via forensic SED fitting

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stab550 ◽

2021 ◽

Vol 503 (3) ◽

pp. 3309-3325

Author(s):

Sabine Bellstedt ◽

Aaron S G Robotham ◽

Simon P Driver ◽

Jessica E Thorne ◽

Luke J M Davies ◽

...

Keyword(s):

Star Formation ◽

Gas Phase ◽

Large Range ◽

Three Dimensional ◽

Cosmic Time ◽

Slowing Down ◽

History Of ◽

Mass Assembly ◽

Star Formation Histories ◽

Cosmic History

ABSTRACT We analyse the metallicity histories of ∼4500 galaxies from the GAMA survey at z < 0.06 modelled by the SED-fitting code ProSpect using an evolving metallicity implementation. These metallicity histories, in combination with the associated star formation histories, allow us to analyse the inferred gas-phase mass–metallicity relation. Furthermore, we extract the mass–metallicity relation at a sequence of epochs in cosmic history, to track the evolving mass–metallicity relation with time. Through comparison with observations of gas-phase metallicity over a large range of redshifts, we show that, remarkably, our forensic SED analysis has produced an evolving mass–metallicity relationship that is consistent with observations at all epochs. We additionally analyse the three-dimensional mass–metallicity–SFR space, showing that galaxies occupy a clearly defined plane. This plane is shown to be subtly evolving, displaying an increased tilt with time caused by general enrichment, and also the slowing down of star formation with cosmic time. This evolution is most apparent at lookback times greater than 7 Gyr. The trends in metallicity recovered in this work highlight that the evolving metallicity implementation used within the SED-fitting code ProSpect produces reasonable metallicity results over the history of a galaxy. This is expected to provide a significant improvement to the accuracy of the SED-fitting outputs.

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