Very close pairs of quasi-stellar objects
نویسندگان
چکیده
It is pointed out that there are now known four very close pairs of QSOs with separations < 5 arcsec and very different redshifts. Several estimates indicates that the probability that they are accidental configurations are small; a conservative estimate of the probability to have four such pairs by random projection yields 3.5 × 10−3. We conclude either that this is further evidence that QSOs have significant non-cosmological redshift components, or that the pairs must be explained by gravitational lensing.
منابع مشابه
ar X iv : a st ro - p h / 96 01 03 1 v 1 9 J an 1 99 6 Very close pairs of Quasi - Stellar Objects
It is pointed out that there are now known four very close pairs of QSOs with separations < 5 arcsec and very different redshifts. Several estimates of the probability that they are accidental configurations range between 10 −7 and 3.5×10 −3. We conclude either that this is further evidence that QSOs have significant non-cosmological redshift components, or that the pairs must be explained by g...
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تاریخ انتشار 1997