| Autor: |
Victor P. Debattista, David J. Liddicott, Oscar A. Gonzalez, Leandro Beraldo e Silva, João A. S. Amarante, Ilin Lazar, Manuela Zoccali, Elena Valenti, Deanne B. Fisher, Tigran Khachaturyants, David L. Nidever, Thomas R. Quinn, Min Du, Susan Kassin |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
The Astrophysical Journal, Vol 946, Iss 2, p 118 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
1538-4357 |
| DOI: |
10.3847/1538-4357/acbb00 |
| Popis: |
In Paper I, we showed that clumps in high-redshift galaxies, having a high star formation rate density (Σ _SFR ), produce disks with two tracks in the [Fe/H]–[ α /Fe] chemical space, similar to that of the Milky Way’s (MW’s) thin+thick disks. Here we investigate the effect of clumps on the bulge’s chemistry. The chemistry of the MW’s bulge is comprised of a single track with two density peaks separated by a trough. We show that the bulge chemistry of an N -body + smoothed particle hydrodynamics clumpy simulation also has a single track. Star formation within the bulge is itself in the high-Σ _SFR clumpy mode, which ensures that the bulge’s chemical track follows that of the thick disk at low [Fe/H] and then extends to high [Fe/H], where it peaks. The peak at low metallicity instead is comprised of a mixture of in situ stars and stars accreted via clumps. As a result, the trough between the peaks occurs at the end of the thick disk track. We find that the high-metallicity peak dominates near the mid-plane and declines in relative importance with height, as in the MW. The bulge is already rapidly rotating by the end of the clump epoch, with higher rotation at low [ α /Fe]. Thus clumpy star formation is able to simultaneously explain the chemodynamic trends of the MW’s bulge, thin+thick disks, and the splash. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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