Seeding Cores: A Pathway for Nuclear Star Clusters from Bound Star Clusters in the First Billion Years
Fuente:
arXiv
Salvato in:
| Autori principali: | , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2025
|
| Soggetti: | |
| Accesso online: | |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866916983826546688 |
|---|---|
| author | Garcia, Fred Angelo Batan Ricotti, Massimo Sugimura, Kazuyuki |
| author_facet | Garcia, Fred Angelo Batan Ricotti, Massimo Sugimura, Kazuyuki |
| contents | We model the formation of star clusters in a dwarf galaxy progenitor during the first $700 ~{\rm Myr}$ of cosmic history using a cosmological radiation-hydrodynamic simulation with a sub-grid star formation efficiency (SFE) model calibrated from AU-scale radiation-MHD simulations of molecular clouds with varying mass, density, and metallicity. In comparison to a constant SFE model, our model yields more bursty star formation, a more abundant massive star cluster population, and overall a higher stellar mass. Clouds reach SFEs up to $80\%$, forming bound star clusters (densities $\sim10^{2-4} ~{\rm M_\odot\:pc^{-2}}$, radii $\lesssim 3~{\rm pc}$) resembling those observed by the James Webb Space Telescope (JWST) in strongly lensed galaxies. Star clusters follow a flat power-law mass function ${\rm d}N/{\rm d}\log M \propto M^Γ$ with slope $Γ\sim -0.4$. The most massive star clusters ($10^{4-5} ~{\rm M_\odot}$) grow through mergers and have metallicity spreads of $0.05 - 0.1$ dex that roughly scale with mass. The second burst of star formation produce loosely bound star clusters with higher metallicities: $-1.95 < \log(Z/{\rm Z_\odot}) < -1.50$ at lower SFEs ($2 - 20\%$). At $z \sim 8.7$, a nuclear star cluster (NSC) is seeded, growing $83\%$ of its mass ($ 2.4 \times 10^5 ~{\rm M_\odot}$, $20\%$ of the galaxy's stellar mass) through mergers with pre-existing clusters and the rest through in-situ star formation. The early formation of NSCs has interesting implications for seeding supermassive black holes and the population of $\textit{little red dots}$ recently discovered by JWST at $z \gtrsim 5$ |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2503_08779 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Seeding Cores: A Pathway for Nuclear Star Clusters from Bound Star Clusters in the First Billion Years Garcia, Fred Angelo Batan Ricotti, Massimo Sugimura, Kazuyuki Astrophysics of Galaxies We model the formation of star clusters in a dwarf galaxy progenitor during the first $700 ~{\rm Myr}$ of cosmic history using a cosmological radiation-hydrodynamic simulation with a sub-grid star formation efficiency (SFE) model calibrated from AU-scale radiation-MHD simulations of molecular clouds with varying mass, density, and metallicity. In comparison to a constant SFE model, our model yields more bursty star formation, a more abundant massive star cluster population, and overall a higher stellar mass. Clouds reach SFEs up to $80\%$, forming bound star clusters (densities $\sim10^{2-4} ~{\rm M_\odot\:pc^{-2}}$, radii $\lesssim 3~{\rm pc}$) resembling those observed by the James Webb Space Telescope (JWST) in strongly lensed galaxies. Star clusters follow a flat power-law mass function ${\rm d}N/{\rm d}\log M \propto M^Γ$ with slope $Γ\sim -0.4$. The most massive star clusters ($10^{4-5} ~{\rm M_\odot}$) grow through mergers and have metallicity spreads of $0.05 - 0.1$ dex that roughly scale with mass. The second burst of star formation produce loosely bound star clusters with higher metallicities: $-1.95 < \log(Z/{\rm Z_\odot}) < -1.50$ at lower SFEs ($2 - 20\%$). At $z \sim 8.7$, a nuclear star cluster (NSC) is seeded, growing $83\%$ of its mass ($ 2.4 \times 10^5 ~{\rm M_\odot}$, $20\%$ of the galaxy's stellar mass) through mergers with pre-existing clusters and the rest through in-situ star formation. The early formation of NSCs has interesting implications for seeding supermassive black holes and the population of $\textit{little red dots}$ recently discovered by JWST at $z \gtrsim 5$ |
| title | Seeding Cores: A Pathway for Nuclear Star Clusters from Bound Star Clusters in the First Billion Years |
| topic | Astrophysics of Galaxies |
| url | https://arxiv.org/abs/2503.08779 |