Astron. Astrophys. 327, L1-L4 (1997)

4. Discussion and conclusions

Direct imagery of J03.13 with the PC1 camera clearly reveals that this bright and distant quasar consists of just two point-like components having an angular separation of 0.849 0.001 and magnitude difference m = 2.14 0.03 in V and I.

Low resolution FOS spectra of J03.13 A and B show that these two components are lensed images of a same quasar at redshift = 2.545, with a common absorption line system at = 2.344 and MgII at = 1.085 being only detected in the spectrum of the A component. Assuming that the deflector is associated with the latter system, one could expect that the quasar is located very close to the radial caustic in the source plane (cf. Fig. 6c in Surdej et al. 1988). One would then expect the bright lensed QSO component (A) to be a radially merging double image, with very small angular separation (typically 0.1 ).

From a detailed analysis of our composite PC1 CCD frames, there is no evidence for the presence of additional objects brighter than V = 22.6 (resp. I = 22.1) at angular separations 0.13 from either component A or B.

In Paper I, we have inferred that the apparent magnitude of a galaxy located at z = 1.085 capable of producing a doubly imaged quasar with an angular separation of 0.85 ought to be fainter than R = 22.7 0.5. Our present observations do not preclude the presence of such a galaxy. NICMOS observations of this system in the near IR ought to be very valuable for the detection of such a putative lens.

© European Southern Observatory (ESO) 1997

Online publication: April 6, 1998
helpdesk.link@springer.de