Oxford University Press (OUP), Monthly Notices of the Royal Astronomical Society, 2(461), p. 1898-1916
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This is the accepted manuscript version of an article accepted for publication in Monthly Notices of the Royal Astronomical Society following peer review. The version of record, L. Wang et al; ???GAMA/H-ATLAS: common star formation rate indicators and their dependence on galaxy physical parameters???, MNRAS (2016), 461(2): 1898-1916, first published online June 20, 2016, is available online via doi: https://doi.org/10.1093/mnras/stw1450 Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. ; We compare common star-formation rate (SFR) indicators in the local Universe in the GAMA equatorial fields (around 160 sq. deg.), using ultraviolet (UV) photometry from GALEX, far-infrared (FIR) and sub-millimetre (sub-mm) photometry from H-ATLAS, and Halpha spectroscopy from the GAMA survey. With a high-quality sample of 745 galaxies (median redshift 0.08), we consider three SFR tracers: UV luminosity corrected for dust attenuation using the UV spectral slope beta (SFRUV,corr), Halpha line luminosity corrected for dust using the Balmer decrement (BD) (SFRHalpha,corr), and the combination of UV and IR emission (SFRUV+IR). We demonstrate that SFRUV,corr can be reconciled with the other two tracers after applying attenuation corrections by calibrating IRX (i.e. the IR to UV luminosity ratio) and attenuation in the Halpha (derived from BD) against beta. However, beta on its own is very unlikely to be a reliable attenuation indicator. We find that attenuation correction factors depend on parameters such as stellar mass, z and dust temperature (Tdust), but not on Halpha equivalent width (EW) or Sersic index. Due to the large scatter in the IRX vs beta correlation, when compared to SFRUV+IR, the beta-corrected SFRUV,corr exhibits systematic deviations as a function of IRX, BD and Tdust.