Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics
Scientific paper
2012-03-02
The Astrophysical Journal Letters, Volume 749, Issue 1, L2 (2012)
Astronomy and Astrophysics
Astrophysics
Galaxy Astrophysics
5 pages, 5 figures. Published in ApJL. References are corrected
Scientific paper
10.1088/2041-8205/749/1/L2
From H\alpha narrow band observations, we identified three H\alpha emitting regions in the direction of Magellanic Stream IV (MS IV). They consist of three parallel filaments with 2 arcmin width and 6 -- 30 arcmin length at 12 arcmin intervals. The mean surface brightness of them is $\sim 2 \times 10^{-18}$ erg s$^{-1}$ cm$^{-2}$ arcsec$^{-2}$. Because of their low surface brightness, the regions were not detected in previous H\alpha surveys. In HI map, the position of the filaments overlap MS, suggesting that they are parts of MS, but there also exists a local HI structure. If the filaments associate with MS, the sizes are 30 pc $\times$ 100 -- 500 pc. The filaments lie at the leading edge of a downstream cloud, which supports a shock heating and its propagation (shock cascade) model for the ionizing source. If they are local objects, on the other hand, Fossil Str\"omgren Trails of more than two stars is a possible interpretation, and the sizes would be 0.1 pc $\times$ 0.3 -- 1.5 pc at 180 pc distance. The positional information of the H\alpha filaments presented in this letter enables us future spectroscopic observations to clarify their nature.
Komiyama Yutaka
Yagi Masafumi
Yoshida Michitoshi
No associations
LandOfFree
Candidates of Halpha emitting regions in Magellanic Stream IV cloud 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 Candidates of Halpha emitting regions in Magellanic Stream IV cloud, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Candidates of Halpha emitting regions in Magellanic Stream IV cloud will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-165717