A LOFAR-IRAS cross-match study: the far-infrared radio correlation and
  the 150-MHz luminosity as a star-formation rate
  Aims. We aim to study the far-infrared radio correlation (FIRC) at 150 MHz in
the local Universe (at a median redshift z~0:05) and improve the use of the
rest-frame 150-MHz luminosity, L150, as a star-formation rate (SFR) tracer,
which is unaffected by dust extinction.
  Methods. We cross-match the 60-um selected Revised IRAS Faint Source Survey
Redshift (RIFSCz) catalogue and the 150-MHz selected LOFAR value-added source
catalogue in the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) Spring
Field. We estimate L150 for the cross-matched sources and compare it with the
total infrared (IR) luminosity, LIR, and various SFR tracers.
  Results. We find a tight linear correlation between log L150 and log LIR for
star-forming galaxies, with a slope of 1.37. The median qIR value (defined as
the logarithm of the LIR to L150 ratio) and its rms scatter of our main sample
are 2.14 and 0.34, respectively. We also find that log L150 correlates tightly
with the logarithm of SFR derived from three different tracers, i.e.,
SFR_Halpha based on the Halpha line luminosity, SFR_60 based on the rest-frame
60-um luminosity and SFR_IR based on LIR, with a scatter of 0.3 dex. Our
best-fit relations between L150 and these SFR tracers are, log L150 (Lsun) =
1.35(0.06) x log SFR_Halpha (Msun/yr) + 3.20(0.06), log L150 (Lsun) =
1.31(0.05) x log SFR_60 (Msun/yr) + 3.14(0.06), and log L150 (Lsun) =
1.37(0.05) x log SFR_IR (Msun/yr) + 3.09(0.05), which show excellent agreement
with each other.
