HE 0047-1756: A new gravitationally lensed double QSO

Wisotzki, L.; Schechter, P. L.; Chen, H.-W.;Richstone, D.; Jahnke, K.; Sánchez, S. F.;Reimers, D.. HE 0047-1756: A new gravitationally lensed double QSO. Astronomy and Astrophysics. 2004, Vol. v.419, p.L31-L34 (2004) , p. -2004.

The quasar HE 0047-1756, at z=1.67, is found to be split into two images 1.44 arcsec apart by an intervening galaxy acting as a gravitational lens. The flux ratio for the two components is roughly 3.5:1, depending slightly upon wavelength. The lensing galaxy is seen on images obtained in the i (800 nm) and Ks bands (2.1 μm); there is also a nearby faint object which may be responsible for some shear. The spectra of the two quasar images are nearly identical, but the emission line ratio between the two components scale differently from the continuum. Moreover, the fainter component has a bluer continuum slope than the brighter one. We argue that these small differences are probably due to microlensing. There is evidence for a partial Einstein ring emanating from the brighter image toward the fainter one.
Based in part on observations obtained with the Baade 6.5-m telescope of the Magellan Consortium. Based in part on observations collected at the German-Spanish Astronomical Center, Calar Alto, operated jointly by Max-Planck-Institut für Astronomie and Instituto de Astrofísica de Andalucia (CSIC).