Chemical evolution of local post-starburst galaxies: implications for the mass-metallicity relation

Ho-Hin Leung*, Vivienne Wild, Michail Papathomas, Adam Carnall, Yirui Zheng, Nicholas Fraser Boardman, Cara Wang, Peter H. Johansson

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

1 Downloads (Pure)


We use the stellar fossil record to constrain the stellar metallicity evolution and star-formation histories of the post-starburst (PSB) regions within 45 local PSB galaxies from the MaNGA survey. The direct measurement of the regions’ stellar metallicity evolution is achieved by a new two-step metallicity model that allows for stellar metallicity to change at the peak of the starburst. We also employ a Gaussian process noise model that accounts for correlated errors introduced by the observational data reduction or inaccuracies in the models. We find that a majority of PSB regions (69 per cent at >1σ significance) increased in stellar metallicity during the recent starburst, with an average increase of 0.8 dex and a standard deviation of 0.4 dex. A much smaller fraction of PSBs are found to have remained constant (22 per cent) or declined in metallicity (9 per cent, average decrease 0.4 dex, standard deviation 0.3 dex). The pre-burst metallicities of the PSB galaxies are in good agreement with the mass–metallicity (MZ) relation of local star-forming galaxies. These results are consistent with hydrodynamic simulations, which suggest that mergers between gas-rich galaxies are the primary formation mechanism of local PSBs, and rapid metal recycling during the starburst outweighs the impact of dilution by any gas inflows. The final mass-weighted metallicities of the PSB galaxies are consistent with the MZ relation of local passive galaxies. Our results suggest that rapid quenching following a merger-driven starburst is entirely consistent with the observed gap between the stellar mass–metallicity relations of local star-forming and passive galaxies.
Original languageEnglish
Number of pages24
JournalMonthly Notices of the Royal Astronomical Society
Issue number3
Early online date7 Feb 2024
Publication statusPublished - Mar 2024


  • Methods: statistical
  • Galaxies: abundances
  • Galaxies: evolution
  • Galaxies: starburst
  • Galaxies: stellar content


Dive into the research topics of 'Chemical evolution of local post-starburst galaxies: implications for the mass-metallicity relation'. Together they form a unique fingerprint.

Cite this