Orbit-Superposition Dynamical Modeling of Barred Galaxies

Autor(en)

Behzad Tahmasebzadeh, Ling Zhu, Juntai Shen, Ortwin Gerhard, Glenn van de Ven

Abstrakt

Barred structures are important in understanding galaxy evolution, but they were not included explicitly in most dynamical models for nearby galaxies due to their complicated morphological and kinematic properties. We modify the triaxial orbit-superposition Schwarzschild implementation by van den Bosch et al. to include barred structures explicitly. The gravitational potential is a combination of a spherical dark matter halo and stellar mass; with the 3D stellar density distribution deprojected from the observed 2D image using a two-component deprojection method, including an axisymmetric disk and a triaxial barred bulge. We consider figure rotation of the galaxy with the bar pattern speed as a free parameter. We validate the method by applying it to a mock galaxy with integral field unit (IFU) data created from an N-body simulation with a boxy/peanut or X-shaped bar. Our model fits the observed 2D surface density and all kinematic features well. The bar pattern speed is recovered well with a relative uncertainty smaller than 10%. Based on the internal stellar orbit distribution of the model, we decompose the galaxy into an X-shaped bar, a boxy bulge, a vertically extended structure and a disk, and demonstrate that our model recovers these structures generally well, similar to the true structures in the N-body simulation. Our method provides a realistic way of modeling the bar structure explicitly for nearby barred galaxies with IFU observations.

Organisation(en)

Institut für Astrophysik

Externe Organisation(en)

Chinese Academy of Sciences (CAS), University of the Chinese Academy of Sciences, Shanghai Jiao Tong University, Max-Planck-Institut für extraterrestrische Physik

Journal

The Astrophysical Journal

Band

941

Anzahl der Seiten

16

ISSN

0004-637X

DOI

https://doi.org/10.3847/1538-4357/ac9df6

Publikationsdatum

12-2022

Peer-reviewed

Ja

ÖFOS 2012

103003 Astronomie, 103004 Astrophysik

Schlagwörter

ASJC Scopus Sachgebiete

Astronomy and Astrophysics, Space and Planetary Science

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/a42cc41f-e0be-46d6-8ff8-489f19d8b842