Research Highlights

The Effect of Bars and Transient Spirals on the Vertical Heating in Disk Galaxies

As a mechanism for the continuous vertical heating of stars in the disk of galaxies, an investigation has focused on the role of stellar bars. It is shown that stellar bars formed in disk galaxies can efficiently scatter stars in the vertical direction. A large number of N-body simulations of model disk galaxies including active dark matter particles reveal that the growth rate of the bar is positively correlated with the vertical heating in the inner regions of galaxies. The galactic bar, which is a strong non axisymmetric pattern in the disk, provides a highly anisotropic heating of disk stars. (Saha, Tseng, and Taam, 2010, ApJ, 721:1878–1890)

The left panel corresponds to the particle image showing the face on and two edge on views of an initially axisymmetric disk. The right panel shows the formation of a bar which produces a peanut shaped morphology.