Cosmic dance at z ~ 3: Detecting the host galaxies of the dual AGN system LBQS 0302–0019 and Jil with HAWK-I+GRAAL

Husemann, B.; Bielby, R.; Jahnke, K.; Arrigoni-Battaia, F.; Worseck, G.; Shanks, T.; Wardlow, J.; Scholtz, J.

doi:10.1051/0004-6361/201833363

Cosmic dance at z ~ 3: Detecting the host galaxies of the dual AGN system LBQS 0302–0019 and Jil with HAWK-I+GRAAL

Husemann, B.; Bielby, R.; Jahnke, K.; Arrigoni-Battaia, F.; Worseck, G.; Shanks, T.; Wardlow, J.; Scholtz, J.

Authors

B. Husemann

R. Bielby

K. Jahnke

F. Arrigoni-Battaia

G. Worseck

T. Shanks

J. Wardlow

J. Scholtz

Abstract

We recently discovered that the luminous radio-quiet quasi-stellar objects (QSO) LBQS 0302–0019 at z = 3.286 is likely accompanied by an obscured AGN at 20 kpc projected distance, which we dubbed Jil. It represents the tightest candidate system of an obscured and unobscured dual AGN at z > 3. To verify the dual AGN scenario, we obtained deep Ks band (rest-frame V band) imaging with the VLT/HAWK-I+GRAAL instrument at 0.″4 resolution during science verification in January 2018. We detect the individual host galaxies of the QSO and Jil with estimated stellar masses of log(M⋆/M⊙) = 11.4 ± 0.5 and log(M⋆/M⊙) = 0.9 ± 0.5, respectively. Near-IR spectra obtained with Very Large Telescope-K-band Multi Object Spectrograph (VLT-KMOS) reveal a clear [O III] λ5007 line detection at the location of Jil that does not contribute significantly to the Ks band flux. Both observations therefore corroborate the dual AGN scenario. A comparison to Illustris simulations suggests a parent halo mass of log(Mhalo/M⊙) = 13.2 ± 0.5 for this interacting galaxy system, corresponding to a massive dark matter halo at that epoch.

Citation

Husemann, B., Bielby, R., Jahnke, K., Arrigoni-Battaia, F., Worseck, G., Shanks, T., …Scholtz, J. (2018). Cosmic dance at z ~ 3: Detecting the host galaxies of the dual AGN system LBQS 0302–0019 and Jil with HAWK-I+GRAAL. Astronomy & Astrophysics, 614, Article L2. https://doi.org/10.1051/0004-6361/201833363

Journal Article Type	Article
Acceptance Date	May 23, 2018
Online Publication Date	Jun 14, 2018
Publication Date	Jun 14, 2018
Deposit Date	Jun 28, 2018
Publicly Available Date	Jun 28, 2018
Journal	Astronomy and astrophysics.
Print ISSN	0004-6361
Electronic ISSN	1432-0746
Publisher	EDP Sciences
Peer Reviewed	Peer Reviewed
Volume	614
Article Number	L2
DOI	https://doi.org/10.1051/0004-6361/201833363