The Bulletin of The Korean Astronomical Society (천문학회보)
- Volume 38 Issue 1
- /
- Pages.39-39
- /
- 2013
- /
- 1226-2692(pISSN)
Enhanced Nitrogen in Morphologically Disturbed Blue Compact Galaxies at 0.20 < z < 0.35: Probing Galaxy Merging Features
- Chung, Jiwon (Department of Astronomy and Space Science, Chungnam National University) ;
- Rey, Soo-Chang (Department of Astronomy and Space Science, Chungnam National University) ;
- Sung, Eon-Chang (Korea Astronomy and Space Science Institute) ;
- Yeom, Bum-Suk (Department of Astronomy and Space Science, Chungnam National University) ;
- Humphrey, Andrew (Centro de Astrof'isica da Universidade do Porto) ;
- Yi, Wonhyeong (Department of Astronomy and Space Science, Chungnam National University) ;
- Kyeong, Jaemann (Korea Astronomy and Space Science Institute)
- Published : 2013.04.11
Abstract
We present a study of correlations between the elemental abundances and galaxy morphologies of 91 blue compact galaxies (BCGs) at z=0.20-0.35 with Sloan Digital Sky Survey (SDSS) DR7 data. We classify the morphologies of the galaxies as either 'disturbed' or 'undisturbed', by visual inspection of the SDSS images, and using the Gini coefficient and M20. We derive oxygen and nitrogen abundances using the Te method. We find that a substantial fraction of BCGs with disturbed morphologies, indicative of merger remnants, show relatively high N/O and low O/H abundance ratios. The majority of the disturbed BCGs exhibit higher N/O values at a given O/H value compared to the morphologically undisturbed galaxies, implying more efficient nitrogen enrichment in disturbed BCGs. We detect Wolf-Rayet (WR) features in only a handful of the disturbed BCGs, which appears to contradict the idea that WR stars are responsible for high nitrogen abundance. Combining these results with Galaxy Evolution Explorer (GALEX) GR6 ultraviolet (UV) data, we find that the majority of the disturbed BCGs show systematically lower values of the
Keywords