| Name: | Sagar Sing Goyary |
| Affiliation: | Rajiv Gandhi University |
| Conference ID : | ASI2024_114 |
| Title : | Bending instabilities of m = 1 mode in disc galaxies: interplay between dark matter halo and vertical pressure |
| Authors : | Sagar S. Goyary1, Kanak Saha2, H. Shanjit Singh1, Suchira Sarkar2 |
| Authors Affiliation: | 1 Department Of Physics, Rajiv Gandhi University, Rono Hills, Doimukh, Arunachal Pradesh 791112, India.
2 Inter-University Center for Astronomy and Astrophysics, Ganeshkhind, Pune 411007, India. |
| Mode of Presentation: | Poster |
| Abstract Category : | Galaxies and Cosmology |
| Abstract : | We report a detailed theoretical analysis of the most prevalent m = 1 bending instability in realistic models of disc galaxies in which an exponential stellar disc is under vertical equilibrium and residing in a cold rigid dark matter halo. A quadratic eigenvalue equation describing the bending modes is formulated and solved for the complete eigen spectrum for a set of model disc galaxies by varying their physical properties such as disc scale-height, and dark matter halo mass. It is shown that the vertical pressure gradient force can excite unstable bending modes in such a disc as well as large-scale discrete modes. Further, it is shown that the unstable eigen modes in a thinner disc grow faster than those in a thicker disc. The bending instabilities are found to be suppressed in discs dominated by massive dark matter halo. We estimate the growth time scales and corresponding wavelength of the m = 1 unstable bending modes in Milky Way-like galaxies and discuss their implication. |
