| Globular cluster formation and accretion in ultra-faint dwarf galaxies |
| Thales Gutcke, University of Hawai'i |
| Event Type: Astro Seminar |
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| Time: 2:00 PM - 3:15 PM |
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| Location: 726 Broadway, 940, CCPP Seminar |
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| Abstract: I present a formation scenario for ancient globular cluster-like objects that form in ultra-high resolution cosmological simulations (smallest cell size < 0.1pc, mass resolution Mcell = 4 Msun). The simulations model the formation of dwarf galaxies before Reionzation and follow their evolution to the present day, during which they form 10^6−7 Msun in stellar mass. The employed LYRA simulation model is taylored to include the necessary physics at this resolution scale. It features a multi-phase interstellar medium, individual stars and individual resolved supernova explosions. The clusters display dense stellar profiles, no or little dark matter and ancient stellar populations. The star formation histories of each cluster are short and bursty, but some display multiple stellar populations. The metallicity distributions become sufficiently wide to include stars in the range 10^−4 < Z/Zsun < 1. This is possible due to the fact that these systems are dark matter mini-halos at high redshift, before the onset of Reionization. The dark matter is preferentially stripped as the clusters are accreted onto small dwarf galaxies, with a mean accretion redshift of z~5. Link to the Event Video |