Corrugated velocity patterns in the spiral galaxies: NGC 278, NGC 1058, NGC 2500 & UGC 3574

Sánchez Gil, M. C.; Alfaro, E. J.; Pérez, E.
Memorie della Societa Astronomica Italiana Supplement, v.25, p.86 (2013).


In this work we address the study of the detection in Halpha of a radial corrugation in the vertical velocity field in a sample of four nearly face-on, spiral galaxies. The geometry of the problem is a main criterion in the selection of the sample as well as of the azimuthal angle of the slits. These spatial corrugations must be equally associated with wavy vertical motions in the galactic plane with a strong large-scale consistency. Evidence of these kinematic waves were first detected in the analysis of the rotation curves of spiral galaxies (eg Vaucoleurs & de Vaucaleurs 1963, Pismis 1965), but it was not until 2001 that Alfaro et al. analyzed in more detail the velocity corrugations in NGC 5427 and a possible physical mechanism for their origin. The aim of this study is to analyze the corrugated velocity pattern in terms of the star formation processes. We describe the geometry of the problem and establish its fundamental relationships.