Publications (6)
Results of optical monitoring of 5 SDSS double QSOs with the Nordic Optical Telescope
Danuta Paraficz, Jens Hjorth, ÃrdÃs ElÃasdóttir
We present optical R-band light curves of five SDSS double QSOs (SDSS J0903+5028, SDSS J1001+5027, SDSS J1206+4332, SDSS J1353+1138, SDSS J1335+0118) obtained from monitoring at th…
Gravitational lenses as cosmic rulers: density of dark matter and dark energy from time delays and velocity dispersions
Danuta Paraficz, Jens Hjorth
We show that a cosmic standard ruler can be constructed from the joint measurement of the time delay (dt) between gravitationally lensed quasar images and the velocity dispersion (…
The Hubble constant inferred from 18 time-delay lenses
Danuta Paraficz, Jens Hjorth
We present a simultaneous analysis of 18 galaxy lenses with time delay measurements. For each lens we derive mass maps using pixelated simultaneous modeling with shared Hubble cons…
Extinction Curves of Lensing Galaxies out to z=1
ÃrdÃs ElÃasdóttir, Jens Hjorth, Sune Toft +2
We present a survey of the extinction properties of ten lensing galaxies, in the redshift range z = 0.04 - 1.01, using multiply lensed quasars imaged with the ESO VLT in the optica…
Hubble constant and dark energy inferred from free-form determined time delay distances
Mauro Sereno, Danuta Paraficz
Time delays between multiple images of lensed sources can probe the geometry of the universe. We propose a novel method based on free-form modelling of gravitational lenses to esti…
Where is the matter in the Merging Cluster Abell 2218?
ÃrdÃs ElÃasdóttir, Marceau Limousin, Johan Richard +6
We present a parametric strong lensing model of the cluster Abell 2218 based on HST ACS data. We constrain the lens model using 8 previously known multiply imaged systems, of which…