Corrugations and Star Formation Activity: The Carina-Sagittarius Arm
Abstract
The paper analyzes the vertical structure of the Carina-Sagittarius spiral arm in relation to the 2D density distribution of young star-gas supercomplexes in the Galactic plane. The Z profile is obtained as a cut of the present 3D topography of the Galactic disk in the solar neighborhood along the spiral arm segment contained in it. Spectral analysis of this vertical profile leads to a set of significant frequencies, which are interpreted in terms of a nonlinear oscillatory process with a characteristic wavelength of 2.4 kpc. Kernel density estimation methods from the same cluster sample used to obtain the topographic description are employed to compute the (X, Y) density distribution of young open clusters (YOCs). A neat correlation between YOC density and displacement from the formal Galactic plane is found when this density distribution is compared with the vertical structure. It is suggested that the corrugation phenomenon is caused by 3D nonlinear density waves, leading to the 3D distribution of fertile H I matter, where star formation processes are later able to develop and propagate.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1992
- DOI:
- 10.1086/171949
- Bibcode:
- 1992ApJ...399..576A
- Keywords:
-
- Galactic Structure;
- Spiral Galaxies;
- Star Formation;
- Stellar Activity;
- Density Distribution;
- Density Wave Model;
- Three Dimensional Models;
- Astrophysics;
- GALAXY: STRUCTURE;
- STARS: FORMATION