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

We present X-SHOOTER near-infrared spectroscopy of a large sample of 38luminous ($M_{1450}=-29.0$ to $-24.4$) quasars at $5.78<z<7.54$, which havecomplementary CII observations from ALMA. This X-SHOOTER/ALMA sample providesus with the most comprehensive view of reionization-era quasars to date,allowing us to connect the quasar properties with those of its host galaxy. Inthis work we introduce the sample, discuss data reduction and spectral fitting,and present an analysis of the broad emission line properties. The measuredFeII/MgII flux ratio suggests that the broad line regions of all quasars in thesample are already enriched in iron. We also find the MgII line to be onaverage blueshifted with respect to the CII redshift with a median of$-391\,\rm{km}\,\rm{s}^{-1}$. A significant correlation between the MgII-CIIand CIV-CII velocity shifts indicates a common physical origin. Furthermore, wefrequently detect large CIV-MgII emission line velocity blueshifts in oursample with a median value of $-1848\,\rm{km}\,\rm{s}^{-1}$. While we find allother broad emission line properties not to be evolving with redshift, themedian CIV-MgII blueshift is much larger than found in low-redshift,luminosity-matched quasars ($-800\,\rm{km}\,\rm{s}^{-1}$). Dividing our sampleinto two redshift bins, we confirm an increase of the average CIV-MgIIblueshift with increasing redshift. Future observations of the rest-frameoptical spectrum with the James Webb Space Telescope will be instrumental infurther constraining the possible evolution of quasar properties in the epochof reionization.

The X-SHOOTER/ALMA sample of Quasars in the Epoch of Reionization. I. NIR spectral modeling, iron enrichment and broad emission line properties