Related papers: Image formation for extended sources with the sola…
It is generally thought that galaxies are embedded in dark matter halos extending well beyond their luminous matter. The existence of these galactic halos is mainly derived from the larger than expected velocities of stars and gas in the…
We propose a new point-spread function (PSF) deconvolution algorithm for images of galaxies hosting an active galactic nucleus (AGN), designed to simultaneously enhance the spatial resolution of the host galaxy and remove the bright central…
Compact objects with magnetic dipole are considered as gravitational lenses. The presence of strong magnetic field near the photon sphere can affect the trajectory of light. We compute the deflection angle near the photon sphere on the…
We study the wave optics features of gravitational microlensing by a binary lens composed of a planet and a parent star. In this system, the source star near the caustic line produces a pair of images in which they can play the role of…
With the help of AdS/CFT correspondence, we analyze the holographic Einstein images via the response function of the complex scalar field as a probe wave on the AdS Schwarzschild scalar-tensor-vector gravity (STVG) black hole (BH). We find…
Gravitational lensing can magnify a distant source, revealing structural detail which is normally unresolvable. Recovering this detail through an inversion of the influence of gravitational lensing, however, requires optimisation of not…
We present a lensing and photometric study of the exceptional system SDSS J1538+5817, identified by the SLACS survey. The lens is a luminous elliptical at redshift z=0.143. Using HST public images in two different filters, the presence of…
Gravitational lens models with negative convergence(surface mass density projected onto the lens plane) inspired by modified gravity theories, exotic matter and energy have been recently discussed in such a way that a static and…
We study the Einstein images of a charged Rastall AdS black hole (BH) within the fabric of AdS/CFT correspondence. Considering the holographic setup, we analyze the amplitude of the total response function for various values of model…
Gravitational lensing - the deflection of light rays by gravitating matter - has become a major tool in the armoury of the modern cosmologist. Proposed nearly a hundred years ago as a key feature of Einstein's theory of General Relativity,…
The study of dark matter substructure through strong gravitational lensing has shown enormous promise in probing the properties of dark matter on sub-galactic scales. This approach has already been used to place strong constraints on a wide…
Recovering sharper images from blurred observations, referred to as deconvolution, is an ill-posed problem where classical approaches often produce unsatisfactory results. In ground-based astronomy, combining multiple exposures to achieve…
We have discovered strong gravitational lensing by the galaxy ESO325-G004, in images obtained with the Advanced Camera for Surveys on the Hubble Space Telescope. The lens galaxy is a boxy group-dominant elliptical at z=0.0345, making this…
We report an ultra-bright lensed submillimeter galaxy at $z_{spec}=1.4796$, identified as a result of a full-sky cross-correlation of the AllWISE and Planck compact source catalogs aimed to search for bright submillimeter galaxies at $z…
Gravitational lensing data is frequently collected at low resolution due to instrumental limitations and observing conditions. Machine learning-based super-resolution techniques offer a method to enhance the resolution of these images,…
We use strongly gravitationally lensed (SGL) systems to put additional constraints on a set of holographic dark energy models. Data available in the literature (redshift and velocity dispersion) is used to obtain the Einstein radius and…
It is well known that the solar gravitational field can be considered as a telescope with a prime focus at locations beyond 550 au. In this work we present a new derivation of the wave-optical properties of the system, by adapting the…
We present a multi-wavelength study of the gravitational lens COSMOS J095930+023427 (z=0.89), together with the associated galaxy group located at $z\sim0.7$ along the line of sight and the lensed background galaxy. The source redshift is…
We study the path of light rays passing near a massive object, in the context of the scale invariant equation of the geodesics first obtained by Dirac (1973). Using the exterior Schwarzschild solution for the metric, we derive the complete…
The effect of stars on the lensing properties of the supermassive black hole in the Galactic Center is similar to the effect of planets on microlensing by a star. We show that the dense stellar cluster around SgrA* increases by factors of a…