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 Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

The nature of jets in active galactic nuclei (AGN) in the early Universe andtheir feedback to the host galaxy remain a highly topical question.Observations of the radio structure of high-redshift AGNs enabled by very longbaseline interferometry (VLBI) provide indispensable input into studies oftheir properties and role in the galaxies' evolution. Up to now, only five AGNsat redshift $z > 6$ have been studied with the VLBI technique. VIKJ2318-3113 isa recently discovered quasar at z = 6.44 that has not been imaged with VLBIbefore the current work. Here we present the first VLBI imaging results of thishigh-redshift quasar, with the aim of corroborating its high-resolutionappearance with the physical model of the object. We carried out VLBIphase-referencing observations of VIKJ2318-3113 using the Very Long BaselineArray at two frequencies, 1.6 and 4.7 GHz, and obtained the first view at theradio structure on the milliarcsecond scale. The source was clearly detected at1.6 GHz. We found that almost all of its radio emission comes from the pc-scalecore region. Our dual-frequency observations constrain the spectral index andbrightness temperature of the radio core. Its properties are similar to thoseof other known high-redshift radio-loud AGNs.

VLBI observations of VIK J2318-3113, a quasar at z = 6.44