2003/12/18 by N. D. Morgan, Nicholas D. Morgan, J. A. R. Caldwell +6 · 1 citation
Physics and Astronomy · #Astrophysical Phenomena and Observations #Galaxies: Formation, Evolution, Phenomena #Gamma-ray bursts and supernovae #astro-ph
paper · pdf · doi:10.1086/383295
34 pages, including 9 postscript figures. Submitted to AJ
arxiv created 2003/12/18 · openalex publication_date 2004/05/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31
We report the discovery of two new gravitationally lensed quasars, WFI J2026-4536 and WFI J2033-4723, at respective source redshifts of z = 2.23 and z = 1.66. Both systems are quadruply imaged and have similar PG 1115–like image configurations. WFI J2026-4536 has a maximum image separation of 1 4, a total brightness of g = 16.5, and a relatively simple lensing environment, while WFI J2033-4723 has a maximum image separation of 2 5, an estimated total brightness of g ≈ 17.9, and a more complicated environment of at least six galaxies within 20''. The primary lensing galaxies are detected for both systems after point-spread function subtraction. Several of the broadband flux ratios in these systems show a strong (0.1–0.4 mag) trend with wavelength, suggesting either microlensing or differential extinction through the lensing galaxy. For WFI J2026-4536, the total quasar flux has dimmed by 0.1 mag in the blue but only half as much in the red over 3 months, suggestive of microlensing-induced variations. For WFI J2033-4723, resolved spectra of some of the quasar components reveal emission-line flux ratios that agree better with the macromodel predictions than either the broadband or continuum ratios, also indicative of microlensing. The predicted differential time delays for WFI J2026-4536 are short, ranging from 1 to 2 weeks for the long delay, but are longer for WFI J2033-4723, ranging from 1 to 2 months. Both systems hold promise for future monitoring campaigns aimed at microlensing or time delay studies.