English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Contrary to expectations from scenarios of black hole growth driven by galaxyinteractions and mergers, dual active galactic nuclei (AGN) with kiloparsecseparations are rarely observed and are very difficult to identify, inparticular at high redshifts (i.e. z>2). Focussing on the recently discovereddual AGN system LBQS 0302-0019 at z=3.29, we seek to identify further groupmembers in its environment and to understand their formation history throughdeep high-angular-resolution imaging. We present deep Hubble Space Telescope(HST) Wide-field Camera 3 near-infrared imaging of LBQS 0302-0019. Incombination with ground-based VLT/HAWK-I imaging, we infer accurate sizes,colours, ages, and stellar masses of companion galaxies. We clearly detect fourcompanion objects close to LBQS 0302-0019 that also have faint signatures inthe ground-based images. We constrain light-weighted ages and masses for thetwo most prominent companions, Jil1 and Jil2, to $t_\star=252_{-109}^{+222}$Myrwith $\log(M_\star/[\mathrm{M}_\odot])= 11.2_{-0.1}^{+0.3}$ and$t_{\star}=19_{-14}^{+74}$Myr with $\log(M_\star/[\mathrm{M}_\odot])=9.4_{-0.4}^{+0.9}$, respectively. The HST data also show that the obscured AGN,previously identified by strong nebular HeII emission, is associated with theyoung massive companion Jil2. Because very massive stars of the starburstcannot be solely responsible for the HeII emission, we strengthen our initialconclusion that Jil2 has been hosting an AGN. If the young starburst of Jil2had been accompanied by sustained black hole growth, Jil2 may have contributedHeII-ionising flux to create the large HeII Ly$\alpha$ proximity zone aroundLBQS 0302-0019. Hence, the duration of the current luminous AGN episode of LBQS0302-0019 may have been overestimated.

A meeting at z~3: Young massive galaxies and an AGN within 30kpc of the luminous QSO LBQS0302-0019