2004/07/19 by Gilberto C. Gomez, Donald P. Cox · 3 citations
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics and Cosmic Phenomena #astro-ph
paper · pdf · doi:10.1086/424500
published as Astrophys.J. 615 (2004) 758-766 · Accepted for publication in ApJ. Better quality figures in http://www.astro.umd.edu/~gomez/publica/3d_galaxy-3.pdf
arxiv created 2004/07/19 · openalex publication_date 2004/11/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/04
We generate synthetic observations from the four-arm model we presented previously for the Galactic ISM in the presence of a spiral gravitational perturbation. We find that velocity crowding and diffusion have a strong effect in the longitude-velocity ( l - v ) diagram. The velocity-latitude ( v - b ) diagram presents structures at the expected spiral arm velocities, which can be explained by the off-the-plane structure of the arms presented in previous papers of this series. Such structures are observed in the Leiden/Dwingeloo H I survey. The rotation curve, as measured from the inside of the modeled galaxy, shows similarities with the observed one for the Milky Way, although it has large deviations from the smooth circular rotation corresponding to the background potential. The magnetic field inferred from a synthetic synchrotron map shows a largely circular structure but with interesting deviations in the midplane due to distortion of the field from circularity in the interarm regions.