![]() |
Figure 1: A portion of the FUSE spectrum of Sk -68 80 in the wavelength range between 1015 and 1040 Å. Interstellar atomic absorption lines are labeled above the spectrum. The unlabeled tic marks indicate interstellar H2 absorption lines from the Lyman and Werner bands. |
Open with DEXTER |
![]() |
Figure 2: Atomic absorption profiles from O I, Fe II, P II, and C I in the direction of Sk -68 80, plotted against LSR velocity. Galactic IVC and HVC absorption occurs near +50 km s-1 and +120 km s-1(dotted lines), respectively. Local disk gas is seen at velocities <40 km s-1; absorption from LMC gas occurs at velocities >160 km s-1. Blending lines are labeled within the plot. |
Open with DEXTER |
![]() |
Figure 3: Curves of growth (COG) for atomic and molecular absorption in the IVC towards Sk -68 80. Atomic absorption lines (identified in the upper left corner) fit on a curve of growth with b=5.9+2.8-1.3 km s-1. Molecular hydrogen lines (identified in the lower right corner) fit on a COG with a much lower b value of 1.5+0.8-0.2 km s-1. Typical error bars for the data points in the different regions of the COG are shown on the left hand side. |
Open with DEXTER |
![]() |
Figure 4: Selection of normalized H2 absorption profiles towards Sk -68 80. The dotted lines indicate H2 absorption by intermediate-velocity halo gas near +50 km s-1and possibly high-velocity halo gas near +120 km s-1(5 cases). H2 absorption from local Galactic gas occurs near 0 km s-1. Blends of other lines and their components are also labeled. |
Open with DEXTER |
![]() |
Figure 5:
Rotational excitation of the H2 gas in the IVC
towards Sk -68 80. The two lowest rotational states (J=0,1) can be
fitted to an equivalent Boltzmann temperature of
![]() ![]() |
Open with DEXTER |
![]() |
Figure A.1: Atomic and H2 absorption profiles in direction of Sk -68 82. The strong Fe II line (upper panel) suggests a very similar component strucutre as for Sk -68 80. In contrast to Sk -68 80 (see Fig. 2), C I absorption is present in the HVC component. Weak molecular hydrogen absorption is present at IVC and HVC velocities, but the individual H2 line profiles have very irregular shapes due to small-scale structure in the continuum flux at wavelengths between 1000 and 1080 Å. A cumulative H2 profile from a co-addition of 15 lines is presented in the lower-most panel. |