Dynamical inference for orbit distributions of galaxies - case study of NGC 4550
- Autor(en)
- Stefanie Reiter
- Abstrakt
A key aspect in studying galaxy evolution is the stellar dynamics, within which a galaxy's formation history is encoded. To disentangle the different dynamical components of observed galaxies, it is possible to construct orbit distributions from observations using orbit-based dynamical modeling. This requires the accurate extraction of the stellar kinematics from observed integrated light spectra. The most commonly used software for kinematic extraction, pPXF, results in a parametric description of the line of sight velocity distribution (LOSVD) using Gauss Hermite models. These have difficulty recovering the bimodal LOSVDs of counterrotating galaxies, and we therefore expect as of yet unchecked biases in the dynamical inference. We test this by comparing the dynamical models of well-known counter-rotating galaxy NGC 4550 inferred from stellar kinematics extracted with pPXF to those inferred from an alternative approach using a non-parametric description of the LOSVD, Bayes-LOSVD. This talk will focus on the significant differences we find in the dynamical inference, as well as our ongoing work to address open questions concerning regularization on the orbit space.
- Organisation(en)
- Institut für Astrophysik
- Publikationsdatum
- 03-2024
- Peer-reviewed
- Ja
- ÖFOS 2012
- 103003 Astronomie, 103004 Astrophysik
- Link zum Portal
- https://ucrisportal.univie.ac.at/de/publications/71375bd0-0624-43b2-ac9c-084702aedac3