Gravitationally lensed QSOs are rare objects, only a few hundred objects have been discovered so far. There is growing interest in lensed QSOs due to recent precision measurement of H_0 using the time delay distance.
We have started a project to identify multiple QSO images using the eFEDS X-ray catalogue as a preselected sample of AGN. X-ray selection provides a well defined input sample independent of optical colours which may be affected by blending of the lensing and lensed objects.
The lensed QSOs are identified by using astrometric information from GAIA and
photometry from the WISE, SDSS, Subaru HSC, and DECaLS surveys.
We will present the first candidates identified by our survey.
|Presenter status||eROSITA consortium member|