Large Groups in the Chile-uk Quasar Survey
نویسندگان
چکیده
The Chile-UK quasar survey, a new-generation 140 deg UVX survey to B = 20, is now ∼ 25% complete. The catalogue currently contains 319 quasars and 93 emission line galaxies. Using the minimal-spanning tree method, we have independently confirmed the ∼ 200 h Mpc group of quasars at z ≃ 1.3 discovered by Clowes & Campusano (1991). We have discovered a new ∼ 150 h Mpc group of 13 quasars at median z ≃ 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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تاریخ انتشار 1997