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

We report the discovery of a highly significant concentration of galaxies ata redshift of <z>=3.090. The structure is evident in a redshift histogram ofphotometrically selected ``Lyman break'' objects in a 9' by 18' field in whichwe have obtained 78 spectroscopic redshifts in the range 2.0 < z <3.4. Thedimensions of the structure projected on the plane of the sky are at least11'by 8', or 14h_{70}^{-1} by 10h_{70}^{-1} Mpc (comoving; \Omega_M=1). Theconcentration contains 15 galaxies and one faint (R=21.7) QSO. We consider thestructure in the context of a number of cosmological models and argue thatLyman-break galaxies must be very biased tracers of mass, with an effectivebias on mass scale M~10^{15}M_{\sun} ranging from b~2 for \Omega_M=0.2 to b >~6for \Omega_M=1. In a Cold Dark Matter scenario the large bias values suggestthat individual Lyman-break galaxies are associated with dark halos of massM~10^{12} M_{\sun}, reinforcing the interpretation of these objects as theprogenitors of massive galaxies at the present epoch. Preliminary results ofspectroscopy in additional fields suggest that such large structures are commonat z~3, with about one similar structure per survey field. The implied spacedensity is consistent with the possibility that we are observing moderatelyrich clusters of galaxies in their early non-linear evolution. Finally, thespectrum of one of the QSOs discovered in our survey (z_{em} = 3.356) exhibitsmetal line absorption systems within the 3 redshift bins having the largestnumber of galaxies in field, z = 2.93, 3.09, and 3.28. These results are thefirst from an ongoing ``targeted'' redshift survey designed to explore thenature and distribution of star-forming galaxies in the redshift range 2.7 <~ z<~ 3.4.Comment: 24 pages including 5 ps figures, LaTeX, uses aaspp4.sty, to appear in  the Astrophysical Journal. Also available at  ftp://astro.caltech.edu/users/ccs/spike_preprint.ps.g

A Large Structure of Galaxies at Redshiftz∼ 3 and Its Cosmological Implications