Abstract Details
| Name: GAUTAM SAIKIA Affiliation: TEZPUR UNIVERSITY Conference ID: ASI2018_634 Title : A study of HII regions in the Large Magellanic Cloud using Spitzer and AKARI observations Authors and Co-Authors : Gautam Saikia (Tezpur University), P. Shalima (Regional Institute of Education, Mysore), Rupjyoti Gogoi (Tezpur University), Amit Pathak (Banaras Hindu University) Abstract Type : Poster Abstract Category : Extragalactic astronomy Abstract : The Large Magellanic Cloud (LMC) has long served as an ideal, nearby laboratory to study the influence of massive stars on dust properties because of it's nearly face-on orientation, known distance and high latitude allowing us to resolve and study stars in association with the interstellar gas and dust. The distribution of the dust itself is important for understanding the structure and dynamics of the LMC. The highest reddening occurs in the regions of 30 Doradus (Tarantula Nebula) and the supershell LMC 2 where color excess E(B-V) reaches a maximum of 0.29. The HII region N11 also shows a high reddening with E(B-V) up to 0.24. The HII regions provide an opportunity to study the ionized gas component of the ISM and star formation on a galactic scale. 30 Doradus has filamentary structures which suggests the presence of large scale non-uniform magnetic fields with a large group of blue stars at the centre of the nebula. We have compared the diffuse FUV scattering observed by FUSE telescope with the IR diffuse emission observed by the Spitzer Space Telescope and the AKARI satellite for the same HII locations and observed better FUV-IR correlations for N11 (0.8) as compared to 30 Doradus (0.5). In this work, we have initially modelled the FUV scattered emission from the stars in an arbitrary scattering geometry using a Monte-Carlo based model by Shalima & Murthy [1] to study the dust optical parameters: albedo (α) and asymmetry factor (g). We have then used the SKIRT model [2] for our infrared dust emission modelling and the results are presented here. References: [1] Shalima, P. and Murthy, Jayant. Modelling of dust scattering toward the Coalsack. Monthly Notices of the Royal Astronomical Society, Volume 352, Issue 4, pp. 1319-1322, 2004. [2] Baes, Maarten; Davies, Jonathan I.; Dejonghe, Herwig; Sabatini, Sabina; Roberts, Sarah; Evans, Rhodri; Linder, Suzanne M.; Smith, Rodney M.; de Blok, W. J. G. Radiative transfer in disc galaxies - III. The observed kinematics of dusty disc galaxies. Monthly Notice of the Royal Astronomical Society, Volume 343, Issue 4, pp. 1081-1094, 2003. |