Radio emission at 1.4 GHz from luminous compact galaxies

Abstract

We analyse the properties of the 1.4 GHz continuum emission in 52 star-forming compact luminous galaxies (LCGs). The fluxes of the 1.4 GHz thermal (free-free) component are derived from the extinction-and aperture-corrected fluxes of the Hα emission line. The fraction of the thermal 1.4 GHz emission is shown to be in the range of 2-52 % with a median value of about 15-17 %, and its distribution is close to a log-normal one. Both the thermal and non-thermal radio continuum luminosities are shown to be proportional to the masses of the young stellar population of the LCGs. We discuss the approximation of the ratio of the 1.4 GHz luminosity-to-the mass of the young stellar population as a function of starburst age. The derived approximation is shown to be similar but less clearly defined compared to ones obtained previously for LCGs from their Hα and UV continuum luminosities.

Luminosity function of luminous compact star-forming galaxies

“…The same function is appropriate for the luminosities in the 22 µm IR band, derived using the Wide-field Infrared Survey Explorer (WISE) data and probably for the radio emission at 1.4 GHz (Parnovsky & Izotova 2015). Naturally, the rapid luminosity evolution affects the observed LF.…”

“…with T 0 = 3.2 Myr and the exponent p, which depends on the wavelength (see details in . The same function is appropriate for the luminosities in the 22 µm IR band, derived using the Wide-field Infrared Survey Explorer (WISE) data and probably for the radio emission at 1.4 GHz (Parnovsky & Izotova 2015).…”