The vertical structure of the spiral galaxy NGC 3501: first stages of the formation of a thin metal-rich disc
- Author(s)
- Natascha Sattler, Francesca Pinna, Nadine Neumayer, Jesus Falcón-Barroso, Marie Martig, Dimitri A. Gadotti, Glenn van de Ven, Ivan Minchev
- Abstract
We trace the evolution of the edge-on spiral galaxy NGC 3501, making use of its stellar populations extracted from deep integral-field spectroscopy MUSE observations. We present stellar kinematic and population maps, as well as the star formation history, of the south-western half of the galaxy. The derived maps of the stellar line-of-sight velocity and velocity dispersion are quite regular, show disc-like rotation, and no other structural component of the galaxy. However, maps of the stellar populations exhibit structures in the mass-weighted and light-weighted age, total metallicity, and [Mg/Fe] abundance. These maps indicate that NGC 3501 is a young galaxy, consisting mostly of stars with ages between 2 and 8 Gyr. Also, they show a thicker more extended structure that is metal-poor and α-rich, and another inner metal-rich and α-poor one with smaller radial extension. While previous studies revealed that NGC 3501 shows only one morphological disc component in its vertical structure, we divided the galaxy into two regions: an inner metal-rich mid-plane and a metal-poor thicker envelope. Comparing the star formation history of the inner thinner metal-rich disc and the thicker metal-poor disc, we see that the metal-rich component evolved more steadily, while the metal-poor one experienced several bursts of star formation. We propose this spiral galaxy is being observed in an early evolutionary phase, with a thicker disc already in place and an inner thin disc in an early formation stage. So we are probably witnessing the birth of a future massive thin disc, continuously growing embedded in a preexisting thicker disc.
- Organisation(s)
- Department of Astrophysics
- External organisation(s)
- Max-Planck-Institut für Astronomie, Institute of Astrophysics of the Canary Islands, University of La Laguna, Liverpool John Moores University (LJMU), European Southern Observatory (Germany), Durham University, Leibniz-Institut für Astrophysik Potsdam
- Journal
- Monthly Notices of the Royal Astronomical Society
- Volume
- 520
- Pages
- 3066–3079
- No. of pages
- 14
- ISSN
- 0035-8711
- DOI
- https://doi.org/10.1093/mnras/stad275
- Publication date
- 04-2023
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103003 Astronomy, 103004 Astrophysics
- Keywords
- ASJC Scopus subject areas
- Astronomy and Astrophysics, Space and Planetary Science
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/75220e94-540a-4f06-8479-22e5fa12173b