The VLA-COSMOS 3 GHz Large Project: AGN and host-galaxy properties out to z ≲ 6

I. Delvecchio, V. Smolčić, G. Zamorani, C. Del P. Lagos, S. Berta, J. Delhaize, N. Baran, D. M. Alexander, D. J. Rosario, V. Gonzalez-Perez, O. Ilbert, C. G. Lacey, O. Le Fèvre, O. Miettinen, M. Aravena, M. Bondi, C. Carilli, P. Ciliegi, K. Mooley, M. Novak & 12 others E. Schinnerer, P. Capak, F. Civano, N. Fanidakis, N. Herrera Ruiz, A. Karim, C. Laigle, S. Marchesi, H. J. McCracken, E. Middleberg, M. Salvato, L. Tasca

Research output: Contribution to journalArticle

38 Citations (Scopus)
129 Downloads (Pure)

Abstract

We explore the multiwavelength properties of AGN host galaxies for different classes of radio-selected AGN out to z ≲ 6 via a multiwavelength analysis of about 7700 radio sources in the COSMOS field. The sources were selected with the Very Large Array (VLA) at 3 GHz (10 cm) within the VLA-COSMOS 3 GHz Large Project, and cross-matched with multiwavelength ancillary data. This is the largest sample of high-redshift (z ≲ 6) radio sources with exquisite photometric coverage and redshift measurements available. We constructed a sample of moderate-to-high radiative luminosity AGN (HLAGN) via spectral energy distribution decomposition combined with standard X-ray and mid-infrared diagnostics. Within the remainder of the sample we further identified low-to-moderate radiative luminosity AGN (MLAGN) via excess in radio emission relative to the star formation rates in their host galaxies. We show that at each redshift our HLAGN havesystematically higher radiative luminosities than MLAGN and that their AGN power occurs predominantly in radiative form, while MLAGN display a substantial mechanical AGN luminosity component. We found significant differences in the host properties of the two AGN classes, as a function of redshift. At z < 1.5, MLAGN appear to reside in significantly more massive and less star-forming galaxies compared to HLAGN. At z > 1.5, we observed a reversal in the behaviour of the stellar mass distributions with the HLAGN populating the higher stellar mass tail. We interpret this finding as a possible hint of the downsizing of galaxies hosting HLAGN, with the most massive galaxies triggering AGN activity earlier than less massive galaxies, and then fading to MLAGN at lower redshifts. Our conclusion is that HLAGN and MLAGN samples trace two distinct galaxy and AGN populations in a wide range of redshifts, possibly resembling the radio AGN types often referred to as radiative- and jet-mode (or high- and low-excitation), respectively, whose properties might depend on the different availability of cold gas supplies.

Original languageEnglish
Article numberA3
JournalAstronomy and Astrophysics
Volume602
DOIs
Publication statusPublished - 1 Jun 2017

Fingerprint

Very Large Array (VLA)
luminosity
galaxies
radio
stellar mass
COSMOS
project
gas supply
cold gas
fading
radio emission
star formation rate
spectral energy distribution
mass distribution
excitation
availability

Cite this

Delvecchio, I. ; Smolčić, V. ; Zamorani, G. ; Lagos, C. Del P. ; Berta, S. ; Delhaize, J. ; Baran, N. ; Alexander, D. M. ; Rosario, D. J. ; Gonzalez-Perez, V. ; Ilbert, O. ; Lacey, C. G. ; Le Fèvre, O. ; Miettinen, O. ; Aravena, M. ; Bondi, M. ; Carilli, C. ; Ciliegi, P. ; Mooley, K. ; Novak, M. ; Schinnerer, E. ; Capak, P. ; Civano, F. ; Fanidakis, N. ; Herrera Ruiz, N. ; Karim, A. ; Laigle, C. ; Marchesi, S. ; McCracken, H. J. ; Middleberg, E. ; Salvato, M. ; Tasca, L. / The VLA-COSMOS 3 GHz Large Project : AGN and host-galaxy properties out to z ≲ 6. In: Astronomy and Astrophysics. 2017 ; Vol. 602.
@article{24eedffa29b14c3b80132f8c35e44c9a,
title = "The VLA-COSMOS 3 GHz Large Project: AGN and host-galaxy properties out to z ≲ 6",
abstract = "We explore the multiwavelength properties of AGN host galaxies for different classes of radio-selected AGN out to z ≲ 6 via a multiwavelength analysis of about 7700 radio sources in the COSMOS field. The sources were selected with the Very Large Array (VLA) at 3 GHz (10 cm) within the VLA-COSMOS 3 GHz Large Project, and cross-matched with multiwavelength ancillary data. This is the largest sample of high-redshift (z ≲ 6) radio sources with exquisite photometric coverage and redshift measurements available. We constructed a sample of moderate-to-high radiative luminosity AGN (HLAGN) via spectral energy distribution decomposition combined with standard X-ray and mid-infrared diagnostics. Within the remainder of the sample we further identified low-to-moderate radiative luminosity AGN (MLAGN) via excess in radio emission relative to the star formation rates in their host galaxies. We show that at each redshift our HLAGN havesystematically higher radiative luminosities than MLAGN and that their AGN power occurs predominantly in radiative form, while MLAGN display a substantial mechanical AGN luminosity component. We found significant differences in the host properties of the two AGN classes, as a function of redshift. At z < 1.5, MLAGN appear to reside in significantly more massive and less star-forming galaxies compared to HLAGN. At z > 1.5, we observed a reversal in the behaviour of the stellar mass distributions with the HLAGN populating the higher stellar mass tail. We interpret this finding as a possible hint of the downsizing of galaxies hosting HLAGN, with the most massive galaxies triggering AGN activity earlier than less massive galaxies, and then fading to MLAGN at lower redshifts. Our conclusion is that HLAGN and MLAGN samples trace two distinct galaxy and AGN populations in a wide range of redshifts, possibly resembling the radio AGN types often referred to as radiative- and jet-mode (or high- and low-excitation), respectively, whose properties might depend on the different availability of cold gas supplies.",
keywords = "Galaxies: active, Galaxies: evolution, Galaxies: nuclei, Radio continuum: galaxies",
author = "I. Delvecchio and V. Smolčić and G. Zamorani and Lagos, {C. Del P.} and S. Berta and J. Delhaize and N. Baran and Alexander, {D. M.} and Rosario, {D. J.} and V. Gonzalez-Perez and O. Ilbert and Lacey, {C. G.} and {Le F{\`e}vre}, O. and O. Miettinen and M. Aravena and M. Bondi and C. Carilli and P. Ciliegi and K. Mooley and M. Novak and E. Schinnerer and P. Capak and F. Civano and N. Fanidakis and {Herrera Ruiz}, N. and A. Karim and C. Laigle and S. Marchesi and McCracken, {H. J.} and E. Middleberg and M. Salvato and L. Tasca",
year = "2017",
month = "6",
day = "1",
doi = "10.1051/0004-6361/201629367",
language = "English",
volume = "602",
journal = "ASTRONOMY & ASTROPHYSICS",
issn = "0004-6361",
publisher = "EDP SCIENCES S A",

}

Delvecchio, I, Smolčić, V, Zamorani, G, Lagos, CDP, Berta, S, Delhaize, J, Baran, N, Alexander, DM, Rosario, DJ, Gonzalez-Perez, V, Ilbert, O, Lacey, CG, Le Fèvre, O, Miettinen, O, Aravena, M, Bondi, M, Carilli, C, Ciliegi, P, Mooley, K, Novak, M, Schinnerer, E, Capak, P, Civano, F, Fanidakis, N, Herrera Ruiz, N, Karim, A, Laigle, C, Marchesi, S, McCracken, HJ, Middleberg, E, Salvato, M & Tasca, L 2017, 'The VLA-COSMOS 3 GHz Large Project: AGN and host-galaxy properties out to z ≲ 6' Astronomy and Astrophysics, vol. 602, A3. https://doi.org/10.1051/0004-6361/201629367

The VLA-COSMOS 3 GHz Large Project : AGN and host-galaxy properties out to z ≲ 6. / Delvecchio, I.; Smolčić, V.; Zamorani, G.; Lagos, C. Del P.; Berta, S.; Delhaize, J.; Baran, N.; Alexander, D. M.; Rosario, D. J.; Gonzalez-Perez, V.; Ilbert, O.; Lacey, C. G.; Le Fèvre, O.; Miettinen, O.; Aravena, M.; Bondi, M.; Carilli, C.; Ciliegi, P.; Mooley, K.; Novak, M.; Schinnerer, E.; Capak, P.; Civano, F.; Fanidakis, N.; Herrera Ruiz, N.; Karim, A.; Laigle, C.; Marchesi, S.; McCracken, H. J.; Middleberg, E.; Salvato, M.; Tasca, L.

In: Astronomy and Astrophysics, Vol. 602, A3, 01.06.2017.

Research output: Contribution to journalArticle

TY - JOUR

T1 - The VLA-COSMOS 3 GHz Large Project

T2 - AGN and host-galaxy properties out to z ≲ 6

AU - Delvecchio, I.

AU - Smolčić, V.

AU - Zamorani, G.

AU - Lagos, C. Del P.

AU - Berta, S.

AU - Delhaize, J.

AU - Baran, N.

AU - Alexander, D. M.

AU - Rosario, D. J.

AU - Gonzalez-Perez, V.

AU - Ilbert, O.

AU - Lacey, C. G.

AU - Le Fèvre, O.

AU - Miettinen, O.

AU - Aravena, M.

AU - Bondi, M.

AU - Carilli, C.

AU - Ciliegi, P.

AU - Mooley, K.

AU - Novak, M.

AU - Schinnerer, E.

AU - Capak, P.

AU - Civano, F.

AU - Fanidakis, N.

AU - Herrera Ruiz, N.

AU - Karim, A.

AU - Laigle, C.

AU - Marchesi, S.

AU - McCracken, H. J.

AU - Middleberg, E.

AU - Salvato, M.

AU - Tasca, L.

PY - 2017/6/1

Y1 - 2017/6/1

N2 - We explore the multiwavelength properties of AGN host galaxies for different classes of radio-selected AGN out to z ≲ 6 via a multiwavelength analysis of about 7700 radio sources in the COSMOS field. The sources were selected with the Very Large Array (VLA) at 3 GHz (10 cm) within the VLA-COSMOS 3 GHz Large Project, and cross-matched with multiwavelength ancillary data. This is the largest sample of high-redshift (z ≲ 6) radio sources with exquisite photometric coverage and redshift measurements available. We constructed a sample of moderate-to-high radiative luminosity AGN (HLAGN) via spectral energy distribution decomposition combined with standard X-ray and mid-infrared diagnostics. Within the remainder of the sample we further identified low-to-moderate radiative luminosity AGN (MLAGN) via excess in radio emission relative to the star formation rates in their host galaxies. We show that at each redshift our HLAGN havesystematically higher radiative luminosities than MLAGN and that their AGN power occurs predominantly in radiative form, while MLAGN display a substantial mechanical AGN luminosity component. We found significant differences in the host properties of the two AGN classes, as a function of redshift. At z < 1.5, MLAGN appear to reside in significantly more massive and less star-forming galaxies compared to HLAGN. At z > 1.5, we observed a reversal in the behaviour of the stellar mass distributions with the HLAGN populating the higher stellar mass tail. We interpret this finding as a possible hint of the downsizing of galaxies hosting HLAGN, with the most massive galaxies triggering AGN activity earlier than less massive galaxies, and then fading to MLAGN at lower redshifts. Our conclusion is that HLAGN and MLAGN samples trace two distinct galaxy and AGN populations in a wide range of redshifts, possibly resembling the radio AGN types often referred to as radiative- and jet-mode (or high- and low-excitation), respectively, whose properties might depend on the different availability of cold gas supplies.

AB - We explore the multiwavelength properties of AGN host galaxies for different classes of radio-selected AGN out to z ≲ 6 via a multiwavelength analysis of about 7700 radio sources in the COSMOS field. The sources were selected with the Very Large Array (VLA) at 3 GHz (10 cm) within the VLA-COSMOS 3 GHz Large Project, and cross-matched with multiwavelength ancillary data. This is the largest sample of high-redshift (z ≲ 6) radio sources with exquisite photometric coverage and redshift measurements available. We constructed a sample of moderate-to-high radiative luminosity AGN (HLAGN) via spectral energy distribution decomposition combined with standard X-ray and mid-infrared diagnostics. Within the remainder of the sample we further identified low-to-moderate radiative luminosity AGN (MLAGN) via excess in radio emission relative to the star formation rates in their host galaxies. We show that at each redshift our HLAGN havesystematically higher radiative luminosities than MLAGN and that their AGN power occurs predominantly in radiative form, while MLAGN display a substantial mechanical AGN luminosity component. We found significant differences in the host properties of the two AGN classes, as a function of redshift. At z < 1.5, MLAGN appear to reside in significantly more massive and less star-forming galaxies compared to HLAGN. At z > 1.5, we observed a reversal in the behaviour of the stellar mass distributions with the HLAGN populating the higher stellar mass tail. We interpret this finding as a possible hint of the downsizing of galaxies hosting HLAGN, with the most massive galaxies triggering AGN activity earlier than less massive galaxies, and then fading to MLAGN at lower redshifts. Our conclusion is that HLAGN and MLAGN samples trace two distinct galaxy and AGN populations in a wide range of redshifts, possibly resembling the radio AGN types often referred to as radiative- and jet-mode (or high- and low-excitation), respectively, whose properties might depend on the different availability of cold gas supplies.

KW - Galaxies: active

KW - Galaxies: evolution

KW - Galaxies: nuclei

KW - Radio continuum: galaxies

UR - http://www.scopus.com/inward/record.url?scp=85020701044&partnerID=8YFLogxK

U2 - 10.1051/0004-6361/201629367

DO - 10.1051/0004-6361/201629367

M3 - Article

VL - 602

JO - ASTRONOMY & ASTROPHYSICS

JF - ASTRONOMY & ASTROPHYSICS

SN - 0004-6361

M1 - A3

ER -