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arXiv · astro-ph/9809146

A Cluster or Filament of Galaxies at Redshift Z=2.5

Ana Campos·Amos Yahil·Rogier A. Windhorst·Eric A. Richards·Sebastian Pascarelle·Chris Impey·Catherine Petry
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Abstract

We report the discovery of 56 new Lyman-alpha-emitting candidates (LECs) at redshift z=2.5 in a field of 8'x14' around two previously known weak radio QSOs and a cosmic microwave background decrement (CMBD) that is plausibly due to the Sunyaev-Zel'dovich effect. Broad-band and medium-band imaging at the redshifted Lyman-alpha wavelength have allowed us to identify the LECs at the redshift of the QSOs. Three of the brightest LECs have been confirmed spectroscopically, with redshifts between z=2.501 and z=2.557; one of them is another QSO. Excluding the third QSO, the four spectroscopically confirmed objects form a 3' filament with a rest-frame velocity dispersion of 1000 km/s lying adjacent to the CMBD, and there is a significant concentration of LECs at the NW end of the filament around the brightest QSO. If confirmed, a velocity dispersion ~1000 km/s on a proper scale ~1 Mpc at redshift z=2.5 would, in and of itself, constrain the cosmological model to low Omega.

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Ana Campos, Amos Yahil, Rogier A. Windhorst, Eric A. Richards, Sebastian Pascarelle, Chris Impey, Catherine Petry. 1998-11-20. A Cluster or Filament of Galaxies at Redshift Z=2.5. https://doi.org/10.1086/311824

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