Barger, K.A.; Haffner, L.M.; Bland-Hawthorn, J.; Warm Ionized Gas Revealed in the Magellanic Bridge Tidal Remnant: Constraining the Baryon Content and the Escaping Ionizing Photons around Dwarf Galaxies

Warm Ionized Gas Revealed in the Magellanic Bridge Tidal Remnant: Constraining the Baryon Content and the Escaping Ionizing Photons around Dwarf Galaxies

by: K. A. Barger, L. M. Haffner, J. Bland-Hawthorn

[arXiv:1305.4932v2, pdf, First author, second, third]

This paper deals with the "bridge" (a remnant of tidal interaction) between the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC). The bridge in this case is a region of ionized gas that stretches between the two clouds. In the paper they present the results of an Hα survey which they did using the Wisconsin Hα Mapper (WHAM) observatory. Some of the interesting results that they got were that the ionization fraction was higher in the bridge than in the SMC tail (36 − 52% compared to 5 − 24%).

They also found that the amount of ionizing radiation from the Milky Way and from extragalactic sources is insufficient to ionize the bridge. Thus they conclude that there needs to be a small amount of ionizing radiation that leaks out of the SMC and the LMC (about 4-5%). This has implications about how dwarf galaxies affect their surroundings and how much they affect their surroundings.

Figure 1 from Barger et al. The contours show column density of H I.
The contours are at 10, 20, 35, and 50 x 10¹⁹ cm⁻².

I thought that this was a good paper that included a good discussion about how they made their observations and how they had to work with their data in order to subtract off atmospheric and other interference. This is relevant to me because in my simulations I am trying to reproduce some of these features observed here so I need to know what people are observing, how they are observing it and what is possible to observe so that I can fit that with my models.