Astronomy and Astrophysics – Astrophysics
Scientific paper
2008-01-16
Astronomy and Astrophysics
Astrophysics
Accepted for publication in the ApJ
Scientific paper
10.1086/529574
We present a new analysis of the diffuse gas in the Magellanic Bridge (RA>3h) based on HST/STIS E140M and FUSE spectra of 2 early-type stars lying within the Bridge and a QSO behind it. We derive the column densities of HI (from Ly\alpha), NI, OI, ArI, SiII, SII, and FeII of the gas in the Bridge. Using the atomic species, we determine the first gas-phase metallicity of the Magellanic Bridge, [Z/H]=-1.02+/-0.07 toward one sightline, and -1.7<[Z/H]<-0.9 toward the other one, a factor 2 or more smaller than the present-day SMC metallicity. Using the metallicity and N(HI), we show that the Bridge gas along our three lines of sight is ~70-90% ionized, despite high HI columns, logN(HI)=19.6-20.1. Possible sources for the ongoing ionization are certainly the hot stars within the Bridge, hot gas (revealed by OVI absorption), and leaking photons from the SMC and LMC. From the analysis of CII*, we deduce that the overall density of the Bridge must be low (<0.03-0.1 cm^-3). We argue that our findings combined with other recent observational results should motivate new models of the evolution of the SMC-LMC-Galaxy system.
Howk Chris J.
Keenan Francis P.
Lehner Nicholas
Smoker Jonathan V.
No associations
LandOfFree
Metallicity and Physical Conditions in the Magellanic Bridge 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 Metallicity and Physical Conditions in the Magellanic Bridge, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Metallicity and Physical Conditions in the Magellanic Bridge will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-160080