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Large groups in the Chile-UK quasar survey

Peter R. Newman·Roger G. Clowes·Luis E. Campusano·Matthew J. Graham
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Abstract

The Chile-UK quasar survey, a new-generation 140 deg^2 UVX survey to B = 20, is now \sim 25 per cent complete. The catalogue currently contains 319 quasars and 93 emission line galaxies. Using the minimal-spanning tree method, we have independently confirmed the \sim 200 h^-1 Mpc group of quasars at z \simeq 1.3 discovered by Clowes & Campusano (1991). We have discovered a new \sim 150 h^-1 Mpc group of 13 quasars at median z \simeq 1.51. The null hypothesis of a uniform, random distribution is rejected at a level of significance of 0.003 for both groups.

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Peter R. Newman, Roger G. Clowes, Luis E. Campusano, Matthew J. Graham. 1997-10-24. Large groups in the Chile-UK quasar survey. https://arxiv.org/abs/astro-ph/9710281

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