相关论文: Gravitational Microlensing of Fractal Sources
Context. Observations of the effect of microlensing in gravitationally lensed quasars could potentially be used to study the structure of the source on distance scales down to the size of the supermassive black hole powering the quasar…
The inner regions of active galaxies host the most extreme and energetic phenomena in the universe including, relativistic jets, supermassive black hole binaries, and recoiling supermassive black holes. However, many of these sources cannot…
Gravitational microlensing is a powerful tool allowing one to probe the structure of quasars on sub-parsec scale. We report recent results, focusing on the broad absorption and emission line regions. In particular microlensing reveals the…
We present a potential test of the origin of the $\gamma$-ray Galactic Centre Excess (GCE). We demonstrate how gravitational microlensing by stellar mass objects along the line of sight to the Galactic Bulge can distinguish between the…
There are $\sim 1$, 0.1 and 0.01 gravitationally lensed X-ray sources per square degree with soft X-ray fluxes exceeding $10^{-15}, 10^{-14}$ and $10^{-13} ergs/s cm^{-2}$ respectively. These sources will be detected serendipitously with…
If at cosmological distances, a small fraction of gamma-ray bursts should be multiply imaged by intervening galaxies or clusters, resulting in the appearance of two very similar bursts from the same location with a relative time delay of…
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…
Recent observations have provided strong evidence for the presence of an Electron Scattering Region (ESR) within the central regions of AGNs. This is responsible for reprocessing emission from the accretion disk into polarised radiation.…
Gravitational Lensing is a UNIQUE tool to constrain the mass distribution of collapsed structures, this is particularly true for galaxies, either on a case by case basis using multiple images of background sources (such as quasars), or…
Cosmological gravitational microlensing is a useful technique for understanding the structure of the inner parts of a quasar, especially the accretion disk and the central supermassive black hole. So far, most of the cosmological…
The components of blazar jets that emit radiation span a factor of $10^{10}$ in scale. The spatial structure of these emitting regions depends on the observed energy. Photons emitted at different sites cross the lens plane at different…
It has been proposed to study gravitational lenses from measurements of the spectrum of the fluctuations of the output current of a quadratic detector. The spatial correlation coefficient of the source is the fundamental parameter of the…
The physical nature of the material responsible for the high--velocity, broad-absorption line features seen in a small fraction of quasar spectra has been the subject of debate since their discovery. This has been especially compounded by…
We present a new method for determining time delays among the light curves of various images in a gravitational lens. The method is based on constructing a simple model for the source variation and forming a chi squared measure of the…
The gravitational field of a galaxy can act as a lens and deflect the light emitted by a more distant object such as a quasar. Strong gravitational lensing causes multiple images of the same quasar to appear in the sky. Since the light in…
We estimate the fraction of mass that is composed of compact objects in gravitational lens galaxies. This study is based on microlensing measurements (obtained from the literature) of a sample of 29 quasar image pairs seen through 20 lens…
The effect of gravitational microlensing on the intensity of gravitational radiation as it propagates through an inhomogeneous medium containing small-scale structure is considered. Lensing by both stars and a power law spectrum of density…
We show that invaluable information on the structure of quasar outflows can be obtained by considering microlensing (ML) induced variability of absorption line troughs in lensed quasars. Depending on the structure and geometry of the…
Microlensings events are predicted for the light coming from cosmological sources. In addition to the microlensing due to gravitation lensing, microlensing produced also by refraction of light due to either ionized, or not, gas clouds can…
A small fraction of all quasars are strongly lensed and multiply imaged, with usually a galaxy acting as the main lens. Some, maybe all of these quasars are also affected by microlensing, the effects of stellar mass objects in the lensing…