# Stability of two-fluid galactic disc under the influence of an external tidal field

## TL;DR

This paper analyzes the stability of a two-fluid galactic disc composed of stars and gas under external tidal forces, deriving a modified dispersion relation and stability criterion to assess its susceptibility to instabilities.

## Contribution

It introduces a new linear stability analysis framework for two-fluid galactic discs influenced by external tidal fields, including a modified dispersion relation and stability criterion.

## Key findings

- Derived a coupled differential equation governing disc instabilities.
- Formulated a modified dispersion relation for stability analysis.
- Discussed potential applications of the stability criterion.

## Abstract

We consider the dynamics of rotationally supported thin galactic disc composed of stars and gas under the influence of external tidal field and derive the coupled differential equations governing the evolution of instabilities. Further linearising the governing equation a modified dispersion relation and stability criterion for appraising the stability of the two fluid galactic disc under the influence of external tidal field is obtained. Possible applications and method for the same are discussed.