Formation of spiral dwarf galaxies: observational data and results of numerical simulation

TL;DR

This paper investigates the formation of spiral patterns in dwarf galaxies through observational data and numerical simulations, revealing constraints on disk properties for spiral structure development.

Contribution

It combines observational analysis with numerical simulations to identify conditions under which spiral patterns can form in dwarf galaxies.

Findings

Small rotation velocities limit spiral formation.

Disk thickness affects gravitational instability.

Maximum gas rotation velocity constrains spiral development.

Abstract

Recent studies show the possibility of the formation of fairly regular and global spiral patterns in dwarf galaxies (dS type). Our sample of observed dwarf objects of this class also includes galaxies with a central stellar bar. The analysis of the observational data provides a small rotation velocity and a small disk component mass for dS galaxies, which is in poor agreement with the spiral structure generation mechanism in isolated dwarfs due to the development of disk gravitational instability. Numerical simulation of the stellar-gaseous disks self-consistent dynamics imposes restrictions on the stellar disk thickness and the maximum gas rotation velocity, at which the gravitational mechanism of spiral formation can still be effective.