The flattening of dark matter halo of Centaurus A galaxy (NGC 5128) out to 40 kpc

Author(s)
Tadeja Veršič, Marina Rejkuba, Magda Arnaboldi, Ortwin Gerhard, Johanna Hartke, Claudia Pulsoni, Glenn van de Ven
Abstract

Cosmological simulations predict dark matter shapes that deviate from spherical symmetry. The exact shape depends on the prescription of the simulation and the interplay between dark matter and baryons. This signature is most pronounced in the diffuse galactic haloes that can be observationally probed with planetary nebulae and globular clusters (GCs). The kinematic observations of these halo tracers support intrinsic triaxial shape for the mass generating the gravitational potential. With discrete axisymmetric modelling of GCs as the halo tracers of NGC 5128 we investigate the overall mass distribution of this nearby giant elliptical galaxy. Our modelling approach constrains $c_{200}$, $(M/L)_{\star, B}$ and inclination. We derive a preliminary $M_{200}\sim 1 \times 10^{12}$ M$_\odot$ and flattening $q_{\mathrm{DM}}\sim 1.3$ indicative of prolate/triaxial halo for NGC 5128.

Organisation(s)
Department of Astrophysics
External organisation(s)
European Southern Observatory (Germany), Max-Planck-Institut für extraterrestrische Physik, University of Turku
Journal
IAU Symposium Proceedings Series
No. of pages
6
ISSN
1743-9213
Publication date
05-2023
Peer reviewed
Yes
Austrian Fields of Science 2012
103003 Astronomy, 103004 Astrophysics
Keywords
Portal url
https://ucrisportal.univie.ac.at/en/publications/1f1e9e1f-77f7-4903-9bee-0c8faeddc20e