FBQ 0951+2635 is classified as a double quasar with a B apparent magnitude of 16.9. When imaged by Schechter, the object is separated into two individual components (A and B), displaying a radio flux ratio of 4 to 1 and separated by 1.1 arcseconds from each other. Follow-up imaging using V and I-bands, have shown these two objects have the same color, with optical observations later discovering there is also a sole bright spot east from the A component and north from the B component.[3] The lensing galaxy of FBQ 0951+2635 is classified as an early-type edge-on spiral galaxy located at (z) 0.260, based on measurements of the lens position on a fundamental plane.[4][5][6] This lensing galaxy also displays a relatively low external sheer from a secondary lens deflector.[7]
The quasar produces pronounced time-delays. Based on R-band light curve measurements using data obtained via Nordic Optical Telescope between March 1999 and June 2001, a short time-delay estimate of 16 ± 2 days was found, although other time-delay estimates put this between the range of 14.2 ± 2.5 and 26.3 ± 7.2 days.[8][9][10] This is mainly attributed to the B component displaying a gradual rise, which in turn follows the rise in the A component. A decrease in flux was observed in the light curves during the last 100 days of observation.[9]
Both components in FBQ 0951+2635 display a long-time-scale fluctuation, given the flux ratio displays both a quasi-flat trend and a bump during the period of 2003-2004,[11] although the B component shows evidence of microlensing shifting both in time and in brightness levels, by -16 days and -1.06 magnitude.[12] The object also shows X-ray variability in addition to time-delays.[13]
Like all quasars, FBQ 0951+2635 is powered by a central supermassive black hole with a mass of 8.9 x 108Mʘ. An observation of its continuum emission region at both wavelengths found the size is 16.24+0.33-0.36 in R-band and 17.04+0.26-0.30 in H-band with its assumed inclination angle of 60°. The slope of the accretion disk temperature profile is 0.50+0.50-0.18 which is shallower but consistent with a standard thin-disk theory.[6]
^Sluse, D.; Chantry, V.; Magain, P.; Courbin, F.; Meylan, G. (February 2012). "COSMOGRAIL: the COSmological MOnitoring of GRAvItational Lenses. X. Modeling based on high-precision astrometry of a sample of 25 lensed quasars: consequences for ellipticity, shear, and astrometric anomalies". Astronomy and Astrophysics. 538: A99. arXiv:1112.0005. Bibcode:2012A&A...538A..99S. doi:10.1051/0004-6361/201015844. ISSN0004-6361.
