Abstract
We explore correlations between extinction-corrected Hα, Hβ and [O II]double luminosities versus 12- and 22-μm band luminosities, based on matching samples from the Sloan Digital Sky Survey (SDSS) and the Wide-field Infrared Survey Explorer (WISE). All the coefficients show strong correlations between Balmer lines and mid-infrared (MIR) luminosities, while the extinction-corrected [O II]double shows a weaker correlation with MIR luminosities. The extinction-corrected emission-line (EL) luminosities are more tightly correlated with linear combinations of EL(obs) and MIR luminosities than with pure MIR luminosities. Linear combinations include both direct and dust-obscured star formation activity in galaxies and offer an improved star formation rate (SFR) indicator for star-forming galaxies. The factor that causes log10LMIR/log10LHα to vary is the metallicity. We find that log10(LHα(obs) + α × LMIR) and log10(L[O II]double(obs) + α × LMIR), rather than pure MIR luminosities or L[O II]double alone, are good proxies for extinction-corrected log10LHα, with a residual that is independent of metallicity. The morphologies have weak correlations with log10LMIR/log10LEL ratios. E(B - V) can be estimated by log10[LMIR/LHα(obs)].
Original language | English |
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Article number | stt2112 |
Pages (from-to) | 97-115 |
Number of pages | 19 |
Journal | Monthly Notices of the Royal Astronomical Society |
Volume | 438 |
Issue number | 1 |
DOIs | |
Publication status | Published - Feb 2014 |
Keywords
- Dust, Extinction
- Galaxies: Evolution
- Galaxies: ISM
- Galaxies: Star formation
- H ii regions
- Infrared: Galaxies