Figure rotation of dark halos in CDM simulations

Details Figure rotation of dark halos in CDM simulations Figure rotation of dark halos in CDM simulations

2007-07-13

arxiv.org/abs/0707.1937v1

Astronomy and Astrophysics

Astrophysics

accepted to MNRAS, 8 pages

Scientific paper

10.1111/j.1365-2966.2007.12096.x

We investigate the figure rotation of dark matter halos identified in Lambda CDM simulations. We find that when strict criteria are used to select suitable halos for study, 5 of the 222 halos identified in our z=0 simulation output undergo coherent figure rotation over a 5h^{-1}Gyr period. We discuss the effects of varying the selection criteria and find that pattern speeds for a much larger fraction of the halos can be measured when the criteria are relaxed. Pattern speeds measured over a 1h^{-1}Gyr period follow a log-normal distribution, centred at Omega_p = 0.25h rad/Gyr with a maximum value of 0.94h rad/Gyr. Over a 5h^{-1}Gyr period, the average pattern speed of a halo is about 0.1h rad/Gyr and the largest pattern speed found is 0.24h rad/Gyr. Less than half of the selected halos showed alignment between their figure rotation axis and minor axis, the exact fraction being somewhat dependent on how one defines a halo. While the pattern speeds observed are lower than those generally thought capable of causing spiral structure, we note that coherent figure rotation is found over very long periods and argue that further simulations would be required before strong conclusions about spiral structure in all galaxies could be drawn. We find no correlation between halo properties such as total mass and the pattern speed.

Affiliated with

Also associated with

No associations

Rating

Figure rotation of dark halos in CDM simulations does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Figure rotation of dark halos in CDM simulations, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Figure rotation of dark halos in CDM simulations will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-60169