An analysis of the local causes and effects of AGN produced jets in galaxies at z~2-3.5

Stevens, Georgia and Warner, Jim and Head, Daniel and Griffin, Stephen and Foster, Alaister and Sobral, David (2020) An analysis of the local causes and effects of AGN produced jets in galaxies at z~2-3.5. Notices of Lancaster Astrophysics (NLUAstro), 2. pp. 1-15.

Text (BAHAMAS_NLUAstro_2_1)
BAHAMAS_NLUAstro_2_1.pdf - Published Version
Download (1MB)

Abstract

We investigate the radio, X-Ray and far-infrared properties of active galactic nuclei (AGN) with strong radio jets at 2.2 < z < 3.5 in the COSMOS field and compare them to AGN without obvious radio jets at similar redshift. We identify 4 jet producing AGNs in the SC4K sample of distant Lyman-α emitting sources and 8 in the VLA radio catalogue, with 2 sources being represented in both, implying a jet fraction of 0.13±0.04% in Lyα emitters and 0.71±0.08% in the general radio-selected population. We find an average radio luminosity for the jets of (2.27±0.01)×10^25 W/Hz in the 3GHz band and (3.10±0.01)×10^25 W/Hz in the 1.4GHz band. We find that the average accretion rate of the AGNs with jets is 0.141+-0.07 M_sun/yr which is lower than the average of the radio AGN without jets, of 0.271+-0.091M_sun/yr. The star formation rate based on the far-infrared is found to be higher for AGN without jets o(~279 M_sun/yr) and to be a third of that value for AGN with jets (~92 M_sun/yr). All the jet producing AGNs we found at z < 3 had an X-ray hardness > 0 and average of 0.41±0.21, higher than the average for AGN without jets of 0.14±0.47. We conclude that the presence of jets may inhibit the AGN’s current activity, due to the large size and luminosity of jets, the energy and matter distributions are altered in such a way that the galaxy’s SFR and BHAR are impacted noticeably, agreeing with previous research and findings.