101. GAMA/H-ATLAS: Common star formation rate indicators and their dependence on galaxy physical parameters
- Author
-
Wang, L, Norberg, P, Gunawardhana, MLP, Heinis, S, Baldry, IK, Bland-Hawthorn, J, Bourne, N, Brough, S, Brown, MJI, Cluver, ME, Cooray, A, da Cunha, E, Driver, SP, Dunne, L, Dye, S, Eales, S, Grootes, MW, Holwerda, BW, Hopkins, AM, Ibar, E, Ivison, R, Lacey, C, Lara-Lopez, MA, Loveday, J, Maddox, SJ, Michałowski, MJ, Oteo, I, Owers, MS, Popescu, CC, Smith, DJB, Taylor, EN, Tuffs, RJ, van der Werf, P, Wang, L, Norberg, P, Gunawardhana, MLP, Heinis, S, Baldry, IK, Bland-Hawthorn, J, Bourne, N, Brough, S, Brown, MJI, Cluver, ME, Cooray, A, da Cunha, E, Driver, SP, Dunne, L, Dye, S, Eales, S, Grootes, MW, Holwerda, BW, Hopkins, AM, Ibar, E, Ivison, R, Lacey, C, Lara-Lopez, MA, Loveday, J, Maddox, SJ, Michałowski, MJ, Oteo, I, Owers, MS, Popescu, CC, Smith, DJB, Taylor, EN, Tuffs, RJ, and van der Werf, P
- Abstract
We compare common star formation rate (SFR) indicators in the local Universe in the Galaxy and Mass Assembly (GAMA) equatorial fields (~160 deg2), using ultraviolet (UV) photometry from GALEX, far-infrared and sub-millimetre (sub-mm) photometry from Herschel Astrophysical Terahertz Large Area Survey, and Hα spectroscopy from the GAMA survey. With a high-quality sample of 745 galaxies (median redshift 〈z〉 = 0.08), we consider three SFR tracers: UV luminosity corrected for dust attenuation using the UV spectral slope β (SFRUV, corr), Hα line luminosity corrected for dust using the Balmer decrement (BD) (SFRHα, corr), and the combination of UV and infrared (IR) emission (SFRUV + IR). We demonstrate that SFRUV, corr can be reconciled with the other two tracers after applying attenuation corrections by calibrating Infrared excess (IRX; i.e. the IR to UV luminosity ratio) and attenuation in the Hα (derived from BD) against β. However, β, 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 (M*), z and dust temperature (Tdust), but not on Hα equivalent width or Sérsic index. Due to the large scatter in the IRX versus β correlation, when compared to SFRUV + IR, the β-corrected SFRUV, corr exhibits systematic deviations as a function of IRX, BD and Tdust.
- Published
- 2016