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

Daddi et al. have recently reported strong clustering of a population of redgalaxies at z~3 in the Hubble Deep Field-South. Fitting the observed angularclustering with a power law of index -0.8, they infer a comoving correlationlength r_0~8 Mpc/h; for a standard cosmology, this r_0 would imply that the redgalaxies reside in rare, M>10^{13} Msun/h halos, with each halo hosting ~100galaxies to match the number density of the population. Using the framework ofthe halo occupation distribution (HOD) in a $\Lambda$CDM universe, we show thatthe Daddi et al. data can be adequately reproduced by less surprising models,e.g., models with galaxies residing in halos of mass M>M_min=6.3x10^{11} Msun/hand a mean occupation Navg(M)=1.4(M/M_min)^{0.45} above this cutoff. Theresultant correlation functions do not follow a strict power law, showinginstead a clear transition from the 1-halo dominated regime, where the twogalaxies of each pair reside in the same dark matter halo, to the 2-halodominated regime, where the two galaxies of each pair are from different halos.The observed high-amplitude data points lie in the one-halo-dominated regime,so these HOD models are able to explain the observations despite having smallercorrelation lengths, r_0~5 Mpc/h. HOD parameters are only loosely constrainedby the current data because of large sample variance and the lack of clusteringinformation on scales that probe the 2-halo regime. If our explanation of thedata is correct, then future observations covering a larger area should showthat the large scale correlations lie below a \theta^{-1.8} extrapolation ofthe small scale points. Our models of the current data suggest that the redgalaxies are somewhat more strongly clustered than UV-selected Lyman-breakgalaxies and have a greater tendency to reside in small groups.Comment: 16 pages, 2 figures. To appear in ApJ (July 20th, 2004). Minor  revisions to match the version in pres

Interpreting the Observed Clustering of Red Galaxies atz∼ 3