Ultraviolet images of the gravitationally lensed quadruple quasar Q2237+0305 with the HST WFPC2
Abstract
We present and analyse observations of the quadruple lensed quasar Q2237+0305, obtained with the HST WFPC2 camera in the F336W and F300W filters. 25 exposures were performed within 15 h real time on 1995 November 3. On a time-scale of 3–4 h, we observe no variation in component A greater than 0.02 mag. The other components remain constant over a period of 10 h to within about 0.05 mag. In the final 5 h there is some evidence (not conclusive) for variation of component D by about 0.1 mag. The exposures indicate that component A is brighter than component B by about 0.3 mag. Components C and D are fainter than component A by about 1.3 and 1.4 mag respectively. Our results place an upper limit on any fifth (central) component of 6.5 mag fainter than component A.