Survey of Ovi absorption in the Large Magellanic Cloud

• Published in: Monthly notices of the Royal Astronomical Society 2011-04, Vol.412 (2), p.1105
• Main Authors: Pathak, A, Pradhan, A. C, Sujatha, N. V, Murthy, J
• Format: Article
• Language: English
• Subjects: Stars & galaxies; Ultraviolet astronomy
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1111/j.1365-2966.2010.17964.x

We present a survey of interstellar Ovi absorption in the Large Magellanic Cloud (LMC) towards 70 lines of sight based on Far Ultraviolet Spectroscopic Explorer (FUSE) observations. The survey covers Ovi absorption in a large number of objects in different environmental conditions of the LMC. Overall, a high abundance of Ovi is present in active and inactive regions of the LMC with mean logN(Ovi) = 14.23atomscm-2. There is no correlation observed between Ovi absorption and emissions from the hot gas (X-ray surface brightness) or the warm gas (Hα surface brightness). Ovi absorption in the LMC is patchy and the properties are similar to that of the Milky Way (MW). In comparison to the Small Magellanic Cloud (SMC), Ovi is lower in abundance even though SMC has a lower metallicity compared to the LMC and the MW. We present observations in 10 superbubbles of the LMC of which we detect Ovi absorption in five superbubbles for the first time and the superbubbles show an excess Ovi absorption of about 40 per cent compared to non-superbubble lines of sight. We have also studied the properties of Ovi absorption in the 30 Doradus region. Even though Ovi does not show any correlation with X-ray emission for the LMC, a good correlation between logN(Ovi) and X-ray surface brightness for 30 Doradus region is present. We also find that Ovi abundance decreases with increasing distance from the star cluster R136. [PUBLICATION ABSTRACT]