TY - JOUR
T1 - EMU/GAMA
T2 - A new approach to characterising radio luminosity functions
AU - Prathap, Jahang
AU - Hopkins, Andrew
AU - Afonso, José
AU - Bilicki, Maciej
AU - Cowley, Michael
AU - Croom, Scott
AU - Gordon, Yjan
AU - Phillipps, Steven
AU - Sadler, Elaine
AU - Shabala, Stanislav
AU - Ahmed, Ummee
AU - Amarantidis, Stergios
AU - Brown, Michael
AU - Carvajal, Rodrigo
AU - Leahy, Denis
AU - Marvil, Joshua
AU - Mukherjee, Tamal
AU - Willingham, Jayde
AU - Zafar, Tayyaba
N1 - © The Author(s), 2025. Published by Cambridge University Press on behalf of Astronomical Society of Australia. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.
PY - 2025/6/2
Y1 - 2025/6/2
N2 - This study characterises the radio luminosity functions (RLFs) for star forming galaxies (SFGs) and active galactic nuclei (AGN) using statistical redshift estimation in the absence of comprehensive spectroscopic data. Sensitive radio surveys over large areas detect many sources with faint optical and infrared counterparts, for which redshifts and spectra are unavailable. This challenges our attempt to understand the population of radio sources. Statistical tools are often used to model parameters (such as redshift) as an alternative to observational data. Using the data from GAMA G23 and EMU early science observations, we explore simple statistical techniques to estimate the redshifts in order to measure the RLFs of the G23 radio sources as a whole and for SFGs and AGN separately. Redshifts and AGN/SFG classifications are assigned statistically for those radio sources without spectroscopic data. The calculated RLFs are compared with existing studies, and the results suggest that the RLFs match remarkably well for low redshift galaxies with an optical counterpart. We use a more realistic high redshift distribution to model the redshifts of (most likely) high redshift radio sources and find that the LFs from our approach match well with measured LFs. We also look at strategies to compare the RLFs of radio sources without an optical counterpart to existing studies.
AB - This study characterises the radio luminosity functions (RLFs) for star forming galaxies (SFGs) and active galactic nuclei (AGN) using statistical redshift estimation in the absence of comprehensive spectroscopic data. Sensitive radio surveys over large areas detect many sources with faint optical and infrared counterparts, for which redshifts and spectra are unavailable. This challenges our attempt to understand the population of radio sources. Statistical tools are often used to model parameters (such as redshift) as an alternative to observational data. Using the data from GAMA G23 and EMU early science observations, we explore simple statistical techniques to estimate the redshifts in order to measure the RLFs of the G23 radio sources as a whole and for SFGs and AGN separately. Redshifts and AGN/SFG classifications are assigned statistically for those radio sources without spectroscopic data. The calculated RLFs are compared with existing studies, and the results suggest that the RLFs match remarkably well for low redshift galaxies with an optical counterpart. We use a more realistic high redshift distribution to model the redshifts of (most likely) high redshift radio sources and find that the LFs from our approach match well with measured LFs. We also look at strategies to compare the RLFs of radio sources without an optical counterpart to existing studies.
KW - radio AGN
KW - radio luminosity functions
KW - radio surveys
KW - statistical techniques
UR - http://www.scopus.com/inward/record.url?scp=105007215775&partnerID=8YFLogxK
UR - https://arxiv.org/abs/2505.11453
U2 - 10.1017/pasa.2025.10044
DO - 10.1017/pasa.2025.10044
M3 - Article
AN - SCOPUS:105007215775
SN - 1323-3580
VL - 42
SP - 1
EP - 15
JO - Publications of the Astronomical Society of Australia
JF - Publications of the Astronomical Society of Australia
M1 - e077
ER -