Are small-scale sub-structures a universal property of galaxy halos? The case of the giant elliptical NGC~5128

Details Are small-scale sub-structures a universal property of galaxy halos? The case of the giant elliptical NGC~5128 Are small-scale sub-structures a universal property of galaxy halos? The case of the giant elliptical NGC~5128

2011-01-12

arxiv.org/abs/1101.2325v1

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

10 pages, 8 figures, MNRAS in press

Scientific paper

We present an analysis of the spatial and chemical sub-structures in a remote halo field in the nearby giant elliptical galaxy Centaurus A (NGC~5128), situated at about 38 kpc from the centre of the galaxy. The observations were taken with the Advanced Camera for Surveys instrument on board the Hubble Space Telescope, and reach down to the horizontal branch. In this relatively small 3.8 kpc by 3.8 kpc field, after correcting for Poisson noise, we do not find any statistically strong evidence for the presence of small-scale sub-structures in the stellar spatial distribution on scales greater than 100 pc. However, we do detect the presence of significant small spatial-scale inhomogeneities in the stellar median metallicity over the surveyed field. We argue that these localized chemical substructures could be associated with not-fully mixed debris from the disruption of low mass systems. NGC 5128 joins the ranks of the late-type spiral galaxies the Milky Way, for which the stellar halo appears to be dominated by small-scale spatial sub-structures, and NGC~891, where localized metallicity variations have been detected in the inner extra-planar regions. This suggests that the presence of small-scale sub-structures may be a generic property of stellar halos of large galaxies.

Affiliated with

Also associated with

No associations

Rating

Are small-scale sub-structures a universal property of galaxy halos? The case of the giant elliptical NGC~5128 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 Are small-scale sub-structures a universal property of galaxy halos? The case of the giant elliptical NGC~5128, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Are small-scale sub-structures a universal property of galaxy halos? The case of the giant elliptical NGC~5128 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-264914