The Fornax3D project: intrinsic correlations between orbital properties and the stellar initial mass function
| Autor: | A Poci, R M McDermid, M Lyubenova, I Martín-Navarro, G van de Ven, L Coccato, E M Corsini, K Fahrion, J Falcón-Barroso, D A Gadotti, E Iodice, F Pinna, M Sarzi, P T de Zeeuw, L Zhu |
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| Rok vydání: | 2022 |
| Předmět: |
Astrophysics - astrophysics of galaxies
Galaxies - evolution FOS: Physical sciences Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Galaxies - kinematics and dynamics cD Galaxies - formation Galaxies - stellar content galaxies: elliptical and lenticular galaxies: evolution galaxies: formation galaxies: kinematics and dynamics galaxies: star formation galaxies: stellar content Space and Planetary Science Galaxies - elliptical and lenticular Astrophysics of Galaxies (astro-ph.GA) Galaxies - star formation Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics Astrophysics::Galaxy Astrophysics |
| Zdroj: | Monthly Notices of the Royal Astronomical Society, 2022, Vol.514(3), pp.3660-3669 [Peer Reviewed Journal] Monthly Notices of the Royal Astronomical Society, 514(3), 3660-3669 |
| Popis: | [arXiv Abridged] In this work, we explore new spatially-resolved measurements of the IMF for three edge-on lenticular galaxies in the Fornax cluster. Specifically, we utilise existing orbit-based dynamical models, which re-produce the measured stellar kinematics, in order to fit the new IMF maps within this orbital framework. We then investigate correlations between intrinsic orbital properties and the local IMF. We find that, within each galaxy, the high-angular-momentum, disk-like stars exhibit an IMF which is rich in dwarf stars. The centrally-concentrated pressure-supported orbits have IMF which are similarly rich in dwarf stars. Conversely, orbits at large radius which have intermediate angular momentum exhibit IMF which are markedly less dwarf-rich relative to the other regions of the same galaxy. Assuming that the stars which, in the present-day, reside on dynamically-hot orbits at large radii are dominated by accreted populations, we can interpret these findings as a correlation between the dwarf-richness of a population of stars, and the mass of the host in which it formed. Specifically, deeper gravitational potentials would produce more dwarf-rich populations, resulting in the relative deficiency of dwarf stars which originated in the lower-mass accreted satellites. Conversely, the central and high angular-momentum populations are likely dominated by in-situ stars, which were formed in the more massive host itself. There are also global differences between the three galaxies studied here, of up to $\sim 0.3\ \mathrm{dex}$ in the IMF parameter $\xi$. We find no local dynamical or chemical property which alone can fully account for the IMF variations. Comment: 11 pages. Accepted to MNRAS |
| Databáze: | OpenAIRE |
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