A Fourier Analysis of the Interacting Pair of Galaxies KPG 404 (NGC 5394/95)

Abstract

We present a bi-dimensional Fourier analysis of near-infrared images of KPG 404 (NGC 5394/95). The 2D Fourier analysis shows that NGC 5394 is a H2β galaxy in the DP classification (Block & Puerari 1999). In contrast, NGC 5395 displays a very complex structure which needs a number of Fourier coefficients to be explained. A tightly wound m = 1 (DP class H1α) is the main structure, but other m = 1 and m = 2 coefficients (suggesting spiral arm modulation) are also present in the Fourier spectra. The complex structure of NGC 5395 also suggests a strong interaction in the pair. The m = 1 coefficients can represent a pseudo ring-type structure, resulting of a collision rather than a grazing passage. We conclude that the most probable scenario of the interaction in this pair should take into account a crossing of NGC 5394 through the disk of NGC 5395.