TY - JOUR
T1 - The Imprint of Clump Formation at High Redshift. II. The Chemistry of the Bulge
AU - Debattista, Victor P.
AU - Liddicott, David J.
AU - Gonzalez, Oscar A.
AU - Beraldo e Silva, Leandro
AU - Amarante, João A. S.
AU - Lazar, Ilin
AU - Zoccali, Manuela
AU - Valenti, Elena
AU - Fisher, Deanne B.
AU - Khachaturyants, Tigran
AU - Nidever, David L.
AU - Quinn, Thomas R.
AU - Du, Min
AU - Kassin, Susan
N1 - © 2023. The Author(s). Published by the American Astronomical Society. This is an open access article distributed under the Creative Commons Attribution License, to view a copy of the license, see: https://creativecommons.org/licenses/by/4.0/
PY - 2023/4/7
Y1 - 2023/4/7
N2 - In Paper I, we showed that clumps in high-redshift galaxies, having a high star formation rate density (ΣSFR), 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-ΣSFR 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.
AB - In Paper I, we showed that clumps in high-redshift galaxies, having a high star formation rate density (ΣSFR), 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-ΣSFR 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.
KW - 310
KW - Galaxies and Cosmology
UR - http://www.scopus.com/inward/record.url?scp=85152588365&partnerID=8YFLogxK
U2 - 10.3847/1538-4357/acbb00
DO - 10.3847/1538-4357/acbb00
M3 - Article
SN - 0004-637X
VL - 946
SP - 1
EP - 17
JO - The Astrophysical Journal
JF - The Astrophysical Journal
IS - 2
M1 - 118
ER -