272 datasets found

We present an algorithm for selecting a uniform sample of gravitationally lensed quasar candidates from low-redshift (0.6<z<2.2) quasars brighter than i=19.1 that have...

We report on i-band snapshot observations of 157 Sloan Digital Sky Survey quasars at 4.0<z<5.4 using the Advanced Camera for Surveys on the Hubble Space Telescope (HST) to...

We present results from a survey for gravitationally lensed radio lobes. Lensed lobes are a potentially richer source of information about galaxy mass distributions than lensed...

We present time-series CCD photometry of a field in the newly discovered dwarf spheroidal galaxy in Sagittarius (hereafter Sgr), and of a nearby control field. These data, which...

Microlensing events can be used to directly measure the masses of single field stars to a precision of ~1-10%. The majority of direct mass measurements for stellar and...

Using Gaia data release 2 (GDR2, Cat. I/345), we present an almanac of 2509 predicted microlensing events, caused by 2130 unique lens stars, that will peak between July 25, 2026...

We present a sample of microlensing events discovered in the Difference Image Analysis (DIA) of the OGLE-II images collected during three observing seasons, 1997-1999. 4424...

We present an implementation of the difference image photometry based on the Alard and Lupton optimal PSF matching algorithm. The most important feature distinguishing this...

We present the Catalog of microlensing events detected toward the Galactic bulge in three observing seasons, 1997-1999, during the OGLE-II microlensing survey. The search for...

We present a new high-precision strong-lensing model of PLCK G287.0+32.9, a massive lens galaxy cluster at z=0.383, with the aim of obtaining an accurate estimation of its...

Strongly lensed quasars are fundamental sources for cosmology. The Gaia space mission covers the entire sky with the unprecedented resolution of 0.18" in the optical, making it...

We show how to significantly improve difference image analysis (DIA) of gravitationally lensed quasars over long periods of time using Gaia proper motions. DIA requires the...

In this work, we present a constraint on the abundance of supergiant (SG) stars at redshift z~1, based on recent observations of a strongly lensed arc at this redshift. First we...

We present a detailed strong lensing analysis of the massive and distant (z=0.870) galaxy cluster ACT-CL J0102-4915 (ACT0102, also known as El Gordo), taking advantage of new...

Quasars experiencing strong lensing offer unique viewpoints on subjects related to the cosmic expansion rate, the dark matter profile within the foreground deflectors, and the...

The combination of multi-band imaging from the Hubble Space Telescope with Multi-Unit Spectroscopic Explorer integral field spectroscopy, obtained at the Very Large Telescope,...

One of the rarest types of variability is the phenomenon of gravitational microlensing, a transient brightening of a background star due to an intervening lensing object....

The microlensing signal in the light curves of gravitationally lensed quasars can shed light on the dark matter (DM) composition in their lensing galaxies. Here, we investigate...

We report the discovery and spectroscopic identification of the bright doubly lensed quasar eRASS1 J050129.5-073309 at redshift z=2.47, selected from the first all-sky survey of...

The Hubble tension, revealed by a ~5{sigma} discrepancy between measurements of the Hubble-Lemaitre constant from early and local-Universe observations, is one of the most...