Herschel reveals the obscured star formation in HiZELS Hα emitters at z = 1.47

We describe the far-infrared (far-IR; rest-frame 8-1000-μm) properties of a sample of 443 Ha- selected star-forming galaxies in the Cosmic Evolution Survey (COSMOS) and Ultra Deep Survey (UDS) fields detected by the High-redshift Emission Line Survey (HiZELS) imaging survey. Sources are identified using narrow-band filters in combination with broad-band photometry to uniformly select Ha (and [O II] if available) emitters in a narrow redshift slice at z = 1.47 ± 0.02.We use a stacking approach in Spitzer-MIPS mid-IR, Herschel-PACS/SPIRE far-IR [from the PACS Evolutionary Prove (PEP) and Herschel Multi-tiered Extragalactic Survey (HerMES)] and AzTEC mm-wave images to describe their typical far-IR properties. We find that HiZELS galaxies with observed Ha luminosities of L(Hα)obs ≈ 108.1-9.1 L⊙ (≈1041.7-42.7 erg s-1) have bolometric far-IR luminosities of typical luminous IR galaxies, L(8-1000 μm) ≈ 1011.41+0.04-0.06 L⊙. Combining the Ha and far-IR luminosities, we derive median star formation rates (SFRs) of SFRHα, FIR = 32 ± 5 M⊙ yr-1 and Ha extinctions of AHα= 1.0 ± 0.2 mag. Perhaps surprisingly, little difference is seen in typical HiZELSextinction levels compared to local star-forming galaxies. We confirm previous empirical stellar mass (M*) to AHa relations and the little or no evolution up to z = 1.47. For HiZELS galaxies (or similar samples) we provide an empirical parametrization of the SFR as a function of rest-frame (u - z) colours and 3.6-μm photometry - a useful proxy to aid in the absence of far-IR detections in high-z galaxies. We find that the observed Ha luminosity is a dominant SFR tracer when rest-frame (u - z) colours are