Probing the Galactic Disk and Halo: Metal Abundances in the Magellanic Stream
Abstract
We derive metal abundance limits for two clouds in the Magellanic Stream using Goddard High Resolution Spectrograph medium resolution spectra of the Seyfert galaxy Fairall 9. We find Si/H >= 0.2 solar and S/H <= 0.9 solar for the +170 km s^-1^ cloud with a N(H I) = 2 x 10^19^ cm^-2^, and Si/H >= 0.07 solar and S/H <= 0.3 solar for the +210 km s^-1^ cloud with a N(H I) = 6 x 10^19^ cm^-2^. These abundance limits rule out the Magellanic Stream as primordial gas. The metal abundance limits are consistent with the Magellanic Cloud abundances. If the two Magellanic Stream clouds have the same metal abundances, then Si/H >= 0.2 solar and S/H <= 0.3 solar for the gas. The ratio Si/S is then >= 0.6 of the solar ratio, suggesting that dust depletion is probably not very significant in the Magellanic Stream.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- December 1994
- DOI:
- 10.1086/187697
- Bibcode:
- 1994ApJ...437L.119L
- Keywords:
-
- Abundance;
- Galactic Halos;
- Intergalactic Media;
- Magellanic Clouds;
- Metallicity;
- Milky Way Galaxy;
- Seyfert Galaxies;
- Absorption Spectroscopy;
- Hubble Space Telescope;
- Ultraviolet Absorption;
- Astronomy;
- GALAXIES: INDIVIDUAL NAME: FAIRALL 9;
- GALAXIES: SEYFERT;
- GALAXIES: MAGELLANIC CLOUDS;
- GALAXY: HALO