1998/09/14 by Sebastian M. Pascarelle, S. M. Pascarelle, Rogier A. Windhorst +1 · 2 citations
Physics and Astronomy · #Advanced Camera for Surveys #Astronomy #Astrophysics #Astrophysics and Cosmic Phenomena #Cosmology #Galaxies: Formation, Evolution, Phenomena #Galaxy #Hubble Deep Field #Hubble space telescope #Physics #Population #Radio Astronomy Observations and Technology #Redshift #Universe #astro-ph
paper · pdf · doi:10.1086/300634
Uses slightly modified AASTeX preprint style file (included). Contains 22 pages, including 5 figures and 2 tables. Accepted for the December issue of the Astronomical Journal
arxiv created 1998/09/14 · openalex publication_date 1998/12/01 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/06
Medium-band imaging with Hubble Space Telescope ( HST ) Wide Field Planetary Camera 2 (WFPC2) in the F410M filter has previously revealed a population of compact Lyα emission objects around the radio galaxy 53W002 at z ≃ 2.4. We report detections of similar objects at z ≃ 2.4 in random, high-latitude HST parallel observations of three additional fields, lending support to the idea that they constitute a widespread population at these redshifts. The three new fields contain 18 Lyα candidates, in contrast to the 17 detected in the deeper exposure of the single WFPC2 field around 53W002. We find substantial differences in the number of candidates from field to field, suggesting that significant large-scale structure is already present in the galaxy distribution at this cosmic epoch. The likely existence of z ≃ 2.4 subgalactic clumps in several random fields shows that these objects may have been common in the early universe and strengthens the argument that such objects may be responsible for the formation of a fraction of the luminous present-day galaxies through hierarchical merging.