G. Burbidge and W. M. Napier 2009 ApJ 706 657 doi:10.1088/0004-637X/706/1/657
G. Burbidge1 and W. M. Napier2
Show affiliationsFollowing the discovery in the 1960s of radio and optical QSOs it was found that some of them lie very close to low-redshift (z ≤ 0.01) spiral galaxies with separations of
2 arcmin. These were discovered both serendipitously by many observers, and systematically by Arp. They are some of the brightest QSOs in radio and optical wavelengths and are very rare. We have carried out a new statistical analysis of most of those galaxy-QSO pairs and find that the configurations have high statistical significance. We show that gravitational microlensing due to stars or other dark objects in the halos of the galaxies apparently cannot account for the excess. Sampling or identification bias likewise seems unable to explain it. Following this up we selected all ~4000 QSOs with g ≤ 18 from a catalog of confirmed QSOs in the Sloan Digital Sky Survey, and compared them with various subsets of galaxies from the RC 3 galaxy catalog. In contrast to the earlier results, no significant excess of such QSOs was found around these galaxies. Possible reasons for the discrepancy are discussed.
galaxies: general; galaxies: statistics; gravitational lensing; quasars: general
Issue 1 (2009 November 20)
Received 2008 December 23, accepted for publication 2009 October 5
Published 2009 November 4
G. Burbidge and W. M. Napier 2009 ApJ 706 657
Jason W. Barnes et al. 2009 ApJ 706 877
M Kohandel et al 2007 Phys. Med. Biol. 52 3665
Donald V. Reames 2009 ApJ 706 844
S.-B. Qian et al 2009 ApJ 706 L96
César Esteban et al. 2009 ApJ 700 654
Kyle M. Walker et al. 2009 ApJ 706 614
C Dress and W Krauth 1995 J. Phys. A: Math. Gen. 28 L597
M. Nonino et al. 2009 ApJS 183 244
Jiang-Tao Li et al. 2009 ApJ 706 693