Chemodynamics of barred galaxies in cosmological simulations: On the Milky Way’s quiescent merger history and in-situ bulge
| Autor: | Isabel Pérez, Simon D. M. White, Antonela Monachesi, Facundo A. Gómez, Francesca Fragkoudi, Federico Marinacci, Melissa Ness, Patricia B. Tissera, Robert J. J. Grand, G. Blázquez-Calero, Ignacio D. Gargiulo, Ruediger Pakmor |
|---|---|
| Přispěvatelé: | Fragkoudi F., Grand R.J.J., Pakmor R., Blazquez-Calero G., Gargiulo I., Gomez F., Marinacci F., Monachesi A., Ness M.K., Perez I., Tissera P., White S.D.M. |
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Milky Way
Metallicity Dynamic bulge [Galaxy] FOS: Physical sciences Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics 01 natural sciences Galaxy: bulge evolution [Galaxy] purl.org/becyt/ford/1 [https] Bulge 0103 physical sciences Galaxy formation and evolution Astrophysics::Solar and Stellar Astrophysics 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics Galaxy: evolution Physics numerical [Methods] Methods: numerical AURIGA 010308 nuclear & particles physics kinematics and dynamics [Galaxies] Galaxies: kinematic Astronomy and Astrophysics purl.org/becyt/ford/1.3 [https] Mass ratio Astrophysics - Astrophysics of Galaxies formation [Galaxies] Galaxy formation [Galaxy] Galaxy: formation Space and Planetary Science Astrophysics of Galaxies (astro-ph.GA) Astrophysics::Earth and Planetary Astrophysics Lindblad resonance |
| Zdroj: | CONICET Digital (CONICET) Consejo Nacional de Investigaciones Científicas y Técnicas instacron:CONICET Digibug. Repositorio Institucional de la Universidad de Granada instname Digibug: Repositorio Institucional de la Universidad de Granada Universidad de Granada (UGR) |
| ISSN: | 3117-0048 |
| Popis: | FF thanks Wilma Trick, Paola Di Matteo, Dimitri Gadotti, and Misha Haywood for comments on earlier versions of themanuscript which greatly improved its clarity, and for many interesting discussions. The authors thank the anonymous referee for a constructive report. The authors thank David Campbell and Adrian Jenkins for generating the initial conditions and selecting the sample of the Auriga galaxies, and Paola Di Matteo for the isolated Nbody simulations used in Appendix B. FM acknowledges support through the Program 'Rita Levi Montalcini' of the Italian MIUR. IG acknowledges financial support from CONICYT Programa Astronomia, Fondo ALMA-CONICYT 2017 31170048. AM acknowledges support from CONICYT FONDECYT Regular grant 1181797. FAG acknowledges financial support from CONICYT through the project FONDECYT Regular Nr. 1181264. FAG, AM, and IG acknowledge funding from the Max Planck Society through a Partner Group grant. This project was developed in part at the 2019 Santa Barbara Gaia Sprint, hosted by the Kavli Institute for Theoretical Physics at the University of California, Santa Barbara. This research was supported in part at KITP by the Heising-Simons Foundation and the National Science Foundation under Grant No. NSF PHY-1748958. We explore the chemodynamical properties of a sample of barred galaxies in the Auriga magnetohydrodynamical cosmological zoom-in simulations, which form boxy/peanut (b/p) bulges, and compare these to the Milky Way (MW). We show that the Auriga galaxies which best reproduce the chemodynamical properties of stellar populations in the MW bulge have quiescent merger histories since redshift z ∼ 3.5: their last major merger occurs at tlookback>12Gyr, while subsequent mergers have a stellar mass ratio of ≤1:20, suggesting an upper limit of a few per cent for the mass ratio of the recently proposed Gaia Sausage/Enceladus merger. These Auriga MW-analogues have a negligible fraction of ex-situ stars in the b/p region (30 per cent) and exhibit X-shaped age and abundance distributions. Examining the discs in our sample, we find that in some cases a star-forming ring forms around the bar, which alters the metallicity of the inner regions of the galaxy. Further out in the disc, bar-induced resonances lead to metal-rich ridges in the Vϕ − r plane – the longest of which is due to the Outer Lindblad Resonance. Our results suggest the Milky Way has an uncommonly quiet merger history, which leads to an essentially in-situ bulge, and highlight the significant effects the bar can have on the surrounding disc. Ministry of Education, Universities and Research (MIUR) CONICYT Programa Astronomia, Fondo ALMA-CONICYT 2017 31170048 CONICYT FONDECYT Regular grant 1181797 CONICYT through the project FONDECYT Regular 1181264 Max Planck Society through a Partner Group grant KITP by the Heising-Simons Foundation National Science Foundation (NSF) NSF PHY-1748958 |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|