The Rees-Sciama effect produced in mergers of galaxy clusters is discussed, and an analytical approximation to compute this effect from numerical simulations is...

We report on a program of spectroscopic observations of gravitationally lensed QSOs with multiple images. We seek to establish whether microlensing is occurring...

We test the recently proposed black hole mass scaling relationship based on the redshift with respect to the quasar's rest frame of the Fe III λλ2039-2113 line...

Context. The gravitational lens system SDSS J1004+4112 was the first known example of a quasar lensed by a galaxy cluster. The interest in this system has been...

We study the broad emission lines in a sample of 11 gravitationally lensed quasars with at least two epochs of observation to identify intrinsic variability and...

Aims. Building on previous works to construct a homogeneous sample of brown dwarfs in binary systems, we investigate microlensing events detected by the Korea...

The influence of microlensing on the profiles of emission lines generated in a biconical geometry is discussed. Microlensing amplification in this anisotropic...

We measure the differential microlensing of the broad emission lines between 18 quasar image pairs in 16 gravitational lenses. We find that the broad emission...