The Galactic Disk-Halo transition - Evidence from Stellar Abundances

Details The Galactic Disk-Halo transition - Evidence from Stellar Abundances The Galactic Disk-Halo transition - Evidence from Stellar Abundances

2008-07-24

arxiv.org/abs/0807.3831v1

Astronomy and Astrophysics

Astrophysics

6 pages, 6 figures. To appear in proceedings of the IAU Symposium No. 254 "The Galaxy Disk in Cosmological Context", Copenhage

Scientific paper

New information on the relations between the Galactic disks, the halo, and satellite galaxies is being obtained from elemental abundances of stars having metallicities in the range -1.5 < [Fe/H] < -0.5. The first results for a sample of 26 halo stars and 13 thick-disk stars observed with the ESO VLT/UVES spectrograph are presented. The halo stars fall in two distinct groups: One group (9 stars) has [alpha/Fe]= 0.30 +-0.03 like the thick-disk stars. The other group (17 stars) shows a clearly deviating trend ranging from [alpha/Fe]= 0.20 at [Fe/H]= -1.3 to [alpha/Fe]= 0.08 at [Fe/H]= -0.8. The kinematics of the stars are discussed and the abundance ratios Na/Fe, Ni/Fe, Cu/Fe and Ba/Y are applied to see if the low-alpha stars are connected to the thin disk or to Milky Way satellite galaxies. Furthermore, we compare our data with simulations of chemical abundance distributions in hierarchically formed stellar halos in a LambdaCDM Universe.

Affiliated with

Also associated with

No associations

Rating

The Galactic Disk-Halo transition - Evidence from Stellar Abundances 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 The Galactic Disk-Halo transition - Evidence from Stellar Abundances, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Galactic Disk-Halo transition - Evidence from Stellar Abundances will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-676428