Abstract
DISCOVERIES of radio-quiet quasars in the vicinity of galaxies1–5, sometimes with possible signs of interactions seem to contradict strongly the statistical analyses6–9 on quasar–galaxy associations, which do not support the previous study10 involving 3C quasars and bright galaxies. In each of these analyses6–10, the calculations used the surface densities of galaxies, because the surface density of quasars is poorly known, but it has been claimed11 that the small angular separations are explicable by chance only if the surface density of quasars is much larger than believed. To test such an assumption we studied the problem by estimating directly the probabilities involved when adopting the most probable values of the density of quasars12,13 at B ∼ 19.0–19.5, that is, μ ∼ 3–5 (deg)−2.
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References
Arp, H. C., Baldwin, J. A. & Wampler, E. J. Astrophys. J. 198, L3–L5 (1975).
Arp, H. C., Willis, A. G. & de Ruiter, H. R. IAU Circ. No. 2750 (1975).
Arp, H. C., Pratt, N. & Sulentic, J. W. Astrophys. J. 199, 565–585 (1975).
Arp, H. C., Sulentic, J. W., Willis, A. G. & de Ruiter, H. R. Astrophys. J. 207, L13–L16 (1976).
Arp, H. C. Astrophys. J. 210, L59–L61 (1976).
Burbidge, G. R., O'Dell, S. L. & Strittmatter, P. A. Astrophys. J. 175, 601–611 (1972).
Hazard, C. & Sanitt, N. Astrophys. Lett. 11, 77–82 (1972).
Bahcall, J. N., McKee, C. F. & Bahcall, N. A. Astrophys. Lett. 10, 147–152 (1972).
Browne, I. W. A. & McEwan, N. J. Mon. Not. R. astr. Soc. 162, 21P–24P (1973).
Burbidge, E. M., Burbidge, G. R., Solomon, P. M. & Strittmatter, P. A. Astrophys. J. 170, 233–240 (1971).
Arp, H. C. IAU Colloq. 37; C.N.R.S. Colloq. 263 (1976).
Sandage, A. R. & Luyten, W. J. Astrophys. J. 155, 913–918 (1969).
Bolton, J. G., Peterson, B. A., Wills, B. J. & Wills, D. Astrophys. J. 210, L1–L3 (1976).
Walker, M. F., Pike, C. D. & Wills, B. J. & Wills, D. Astrophys. J. 210, L1–L3 (1976).
Nieto, J.-L. thesis, Univ. Paris (1976).
Burbidge, G. R., Crowne, A. H. & Smith, H. E. Astrophys. J. Suppl. 33, 113–188 (1977).
Bond, H. E., Kron, R. G. & Spinrad, H. Astrophys. J. 213, 1–7 (1977).
Osmer, P. S. & Smith, M. G. Astrophys. J. 213, 607–618 (1977).
Weedman, D. W. Astrophys. Lett. 9, 49–51 (1971).
Stockton, A. Astrophys. J. 155, L141–L142 (1969).
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NIETO, JL. Quasar–galaxy pairs and surface density of quasars. Nature 270, 411–412 (1977). https://doi.org/10.1038/270411a0
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DOI: https://doi.org/10.1038/270411a0
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