Four-color photometry obtained with the Hubble Space Telescope is consistent with the hypothesis that the light from the quasar 1208+1011 (z = 3.8) is gravitationally lensed. Guided exposures taken with the HST Planetary Camera resolve the quasar image into two point-source components separated by 0″.476 ± 0″.004. The intensity ratio of the components is approximately 4:1 in each of four broad-band HST filters with mean wavelengths of 4352, 5416, 6898, and 8922 Å. The HST photometry, when combined with high-resolution ground-based spectroscopy, rules out the possibility that the secondary component is a Galactic star. The limit on additional point sources is 3% of the brighter image for separations greater than 0″.5 from the primary component and 5% of the brighter component for separations between 0″.1 and 0″.5. If the gravitational lens is an ordinary galaxy, it would not have been detected on the HST images.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science