Name: Ankit Kumar
Affiliation: Indian Institute of Astrophysics, Bangalore
Conference ID : ASI2022_120
Title : Imprints of Dark Matter Halo Shape on Bar Buckling and the Resultant Boxy/Peanut Bulge
Authors : Ankit Kumar, Mousumi Das, Sandeep Kumar Kataria
Abstract Type: Poster
Abstract Category : Extragalactic Astronomy
Abstract : Nearly 2/3 of the spiral galaxies harbor a stellar bar in their centers. The dynamics and morphology of a bar changes significantly during its evolution. Observations of edge-on galaxies have revealed the presence of boxy or peanut structures in their centers. Numerically, it has been shown that such boxy/peanut structures are formed due to bar thickening. One of the bar thickening mechanisms that leads to the formation of boxy/peanut structures is bar buckling, where the bar bends out of the galaxy's plane. In this meeting, we present our recent study of the effect of dark matter halo shape on bar buckling and the formation of boxy/peanut bulges. Using N-body simulations of disk galaxies in oblate, spherical, and prolate dark matter halos, we found that oblate halos delay bar formation, and hence bar buckling as well. In contrast, prolate halos show early bar formation, which leads to early buckling. All of our models go through two buckling events, but the most prolate halo shows three distinct buckling events. Three buckling events cumulatively increase the detectability of buckling events in prolate halos. Given the detection of buckling events in observation is rare, our results suggest that most of the barred galaxies may have spherical or oblate halos rather than prolate halo. Also, prolate halos show a thicker boxy/peanut structure that is a result of multiple bar buckling events.