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arXiv · 1505.06604

The Dust Content and Radiation Fields of Sample of Galaxies in the ELAIS-N1 Field

P. Shalima·Rupjyoti Gogoi·Amit Pathak·Ranjeev Misra·Ranjan Gupta·D. B. Vaidya
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Abstract

The Mid-IR colors ($F_{8}/F_{24}$) of galaxies together with their IR-UV luminosity correlations can be used to get some insight into the relative abundance of the different dust grain populations present in them. The ELAIS-N1 field contains thousands of galaxies which do not have optical spectra but have been observed in the Mid-IR by {\it Spitzer} and UV by {\it GALEX} making it ideal for these studies. As part of this work we have selected a sample of galaxies from the ELAIS-N1 field which have photometric observations in the MIR and UV as well as photometric redshifts from the SDSS database. We put the constraint that the redshifts are $\le$ 0.1, thereby giving us a total of 309 galaxies. We find that the majority of the galaxies in the sample are PAH dominated due to their high MIR flux ratio. We also find a reasonable correlation between the Mid-IR and the UV luminosities out of which the Mid-IR emission from PAHs at 8 $μ$m is marginally better correlated than the 24 $μ$m VSG emission with the UV luminosities. However, if we divide the sample based on their $F_{8}/F_{24}$ ratios which is also an indicator of metallicity, the MIR-UV correlation seems to increase with the $F_{8}/F_{24}$ ratio. But the MIR-UV correlations are not very different for the PAHs and the VSG population within the individual metallicity groups.

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P. Shalima, Rupjyoti Gogoi, Amit Pathak, Ranjeev Misra, Ranjan Gupta, D. B. Vaidya. 2015-05-25. The Dust Content and Radiation Fields of Sample of Galaxies in the ELAIS-N1 Field. https://doi.org/10.1086/682368

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