| Name: Protap Halder |
| Affiliation: Indian Institute of Astrophysics Bangalore |
| Conference ID: ASI2026_284 |
| Title: Investigating the halo-disk shape connection using TNG50 |
| Abstract Type: Poster |
| Abstract Category: Galaxies and Cosmology |
| Author(s) and Co-Author(s) with Affiliation: Protap Halder(Indian Institute of Astrophysics, Bangalore - 560034, India), Dr. Sioree Ansar(Durham University, Durham - DH1 3LE, UK), Prof. Mousumi Das(Indian Institute of Astrophysics, Bangalore - 560034, India) |
| Abstract: Dark Matter (DM) halos play a critical role in galaxy formation and evolution. However, observationally it is challenging to probe the properties of DM halos. In high resolution cosmological simulations galaxy DM halos evolve under realistic environments and are used to study DM halo properties for statistically large galaxy samples. We investigate DM halo shapes of a large sample of galaxies (~900) at redshift, z = 0 from the TNG50 cosmo-magneto-hydrodynamical simulations to study the connection between halo shapes and baryonic disk properties. We used the reduced moments of inertia tensor to obtain three important shape parameters, oblateness (s), asymmetry (q) and triaxiality (T) of DM halos and stellar disks at multiple galactic radii. We examine if halo shapes are correlated to galaxy stellar mass, gas mass fraction and stellar disk shapes. At twice the stellar half-mass radius, the halo and disk triaxialities show a significantly positive spearman correlation coefficient R~84%, which further improves to R~87% upon removing the disturbed/interacting galaxies from the sample. The correlation reduces at larger radii. There is a weak but noticeable correlation between halo shape (s, T) and gas mass fraction and baryon surface densities. We also find that the majority of DM halos have oblate shapes close to the baryonic disk or the inner halo. In 90% of the galaxies in our sample, the minor axis of the host DM halo is aligned (within 23 degrees) to the maximum angular momentum axis of their stellar disk. The findings in this study will add to the understanding of disk-halo shape connection and in making comparisons with galaxy observations. |
