Bar detection in n-body simulation using Fourier analysis

Abstract

Bars are considered to be a common feature in disk galaxies. Since their formation and evolution can be fully studied only using N-body simulations, it is important to refine and improve methods for bar detection and determination of its properties. The most practical and frequently used method is based on Fourier analysis of the face-on density distribution of disk particles. However, criteria for positive bar detection and determination of its parameters are usually biased toward long and strong bars or cases where no other feature is present in the disk (e.g. spiral structure, tidal tails). We propose a new criterion which enables positive bar detection for both weak and short bars, and also successfully distinguishes bar region from other possibly present features.