Deep 1.4 GHz counts show an upturn below a few milliJansky (mJy), corresponding to a more rapid increase in the number of faint sources. This change of slope is thought to be due to the emergence of a new population of radio sources, which does not show up at higher flux densities. Today we know that the faint radio population is a mixture of different classes of objects (AGNs, star-forming galaxies, normal ellipticals and spirals), but the relative fractions are still uncertain and very little is known about the luminosity properties and the redshift distribution of such sources. Understanding whether the dominant triggering process is star formation or nuclear activity has important implications on the study of the star-formation/black-hole-accretion history with radio-selected samples.
Probing the Faint Radio Population Through Multi-Wavelength Information / Prandoni I.; Parma P.; Wieringa M.H.; Gregorini L.; de Ruiter H.R.; Vettolani G.; Ekers R.D.. - STAMPA. - (2005), pp. 446-447. (Intervento presentato al convegno ESO Workshop, ESO astrophysics symposia tenutosi a Venice (Italy) nel 13-16 October 2003).
Probing the Faint Radio Population Through Multi-Wavelength Information
GREGORINI, LORETTA;
2005
Abstract
Deep 1.4 GHz counts show an upturn below a few milliJansky (mJy), corresponding to a more rapid increase in the number of faint sources. This change of slope is thought to be due to the emergence of a new population of radio sources, which does not show up at higher flux densities. Today we know that the faint radio population is a mixture of different classes of objects (AGNs, star-forming galaxies, normal ellipticals and spirals), but the relative fractions are still uncertain and very little is known about the luminosity properties and the redshift distribution of such sources. Understanding whether the dominant triggering process is star formation or nuclear activity has important implications on the study of the star-formation/black-hole-accretion history with radio-selected samples.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
