Who are we (contact us)


Old Q0957+561 data & software: 

Optical Monitoring

HST-STIS Spectra

Simple FORTRAN programs to apply the d2 test (accurate and robust time delay measurements)


Postgraduate Course on GL




Workshop 2004



   ► Photos





Gravitational Lenses (GL) at the University of Cantabria (UC)

Since 1998, the Gravitational LENses and DArk MAtter (GLENDAMA) project is planning, conducting and analyzing observations of gravitationally lensed quasars and related objects. Here below we present our 1999-2014 database, as well as our most recent results and tools





Discovery of SDSS J1442+4055 

(RA = 220.72826, DEC = 40.92655)

As part of an ongoing search for lensed quasars in the SDSS-III database, we found the optically bright, wide separation double quasar SDSS J1442+4055 at z = 2.575 (two images A and B with r ~ 1819 and 2.1 arcsec apart), which has been included in the GLENDAMA list of targets. After a follow-up campaign of lensed quasar candidates at the Maidanak Observatory in May-June 2015, we subtracted two PSFs from the r-band combined frame of SDSS J1442+4055 (exposure time = 3600 s, FWHM ~ 1 arcsec), detecting the main lensing galaxy G1 (see here above). We then taken spectra with SPRAT at the Liverpool Telescope on August 29, 2015 (exposure time = 3000 s, FWHM ~ 1.3 arcsec), confirming the lensed quasar nature of the candidate (see here above). The z of G1 is unknown, the photometric z of G2 (a companion galaxy) is ~ 0.3, and there is also an absorption system in the SDSS spectrum of A at z = 1.946. This lens system has been independently discovered by More et al. (2015)



UC Simulator for ISSIS (WSO-UV)   


(ISSIS latest design)

Crowded-field Image Simulator (CIS)

Download the CIS and related files

About the tool and how it works for GL



Webmaster: goicol(at)unican.es

September 2015