Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2011-10-25
2012 ApJL, 742, L25
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
5 pages, 2 figures, accepted to ApJL
Scientific paper
10.1088/2041-8205/742/2/L25
The stars in the dwarf spheroidal satellite galaxies (dSphs) of the Milky Way are significantly more metal-poor than would be expected from a closed box model of chemical evolution. Gas outflows likely carried away most of the metals produced by the dSphs. Based on previous Keck/DEIMOS observations and models, we calculate the mass in Mg, Si, Ca, and Fe expelled from each of eight dSphs. Essentially, these masses are the differences between the observed amount of metals present in the dSphs' stars today and the inferred amount of metals produced by supernovae. We conclude that the dSphs lost 96% to >99% of the metals their stars manufactured. We apply the observed mass function of Milky Way dSphs to the ejected mass function to determine that a single large dSph, like Fornax, lost more metals over 10 Gyr than all smaller dSphs combined. Therefore, small galaxies like dSphs are not significant contributors to the metal content of the intergalactic medium. Finally, we compare our ejected mass function to previous X-ray measurements of the metal content of the winds from the post-starburst dwarf irregular galaxy NGC 1569. Remarkably, the most recent starburst in that galaxy falls exactly on the ejected mass-stellar mass relation defined by the Milky Way dSphs.
Finlator Kristian
Kirby Evan N.
Martin Crystal L.
No associations
LandOfFree
Metals Removed by Outflows from Milky Way Dwarf Spheroidal Galaxies 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 Metals Removed by Outflows from Milky Way Dwarf Spheroidal Galaxies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Metals Removed by Outflows from Milky Way Dwarf Spheroidal Galaxies will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-96079