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

The discovery in deep near-infrared surveys of a population of massivequiescent galaxies at $z>3$ has given rise to the question of how they came tobe quenched so early in the history of the Universe. Measuring their moleculargas properties can distinguish between physical processes where they stopforming stars due to a lack of fuel versus those where star-formationefficiency is reduced and the gas is retained. We conducted Atacama LargeMillimeter/sub-millimeter Array (ALMA) observations of four quiescent galaxiesat $z=$ 3.5-4.0 found by the Fourstar Galaxy Evolution Survey (ZFOURGE) and aserendipitous optically dark galaxy at $z=3.71$. We aim to investigate thepresence of dust-obscured star-formation and their gas content by observing thedust continuum emission at Band-7 and the atomic carbon [C I]($^3P_1$-$^3P_0$)line at 492.16 GHz. Among the four quiescent galaxies, only one source isdetected in the dust continuum at $\lambda_{\rm obs} = 870 {\rm \mu m}$. Thesub-mm observations confirm their passive nature, and all of them are locatedmore than four times below the main sequence of star-forming galaxies at$z=3.7$. None of the targets are detected in [C I], constraining their gas massfractions to be $<$ 20%. These gas mass fractions are more than three timeslower than the scaling relation for star-forming galaxies at $z=3.7$. Theseresults support scenarios where massive galaxies at $z=$ 3.5-4.0 quench byconsuming/expelling all the gas rather than by reducing the efficiency of theconversion of their gas into stars.

Low star-formation activity and low gas content of quiescent galaxies at $z=$ 3.5-4.0 constrained with ALMA