Related papers: Wide band, tunable gamma-ray lenses
Basing on experiments at SLAC, MAMI, CERN, and on Monte Carlo simulations, we assess the physical limits on efficiency and reachable angles of electron deflection in bent crystals in the energy range from sub-GeV to sub-TeV. We find that…
Very high energy (VHE; E > 100 GeV) gamma-rays provide a unique probe into the non-thermal processes in the universe. The ground-based Imaging Air Cherenkov telescopes (IACTs) for detecting VHE gamma-rays have been perfected, so a…
We present the experimental observation of the superlensing effect in a slab of a one-dimensional photonic crystal made of tilted dielectric elements. We show that this flat lens can achieve subwavelength resolution in different frequency…
The observational progress in the $\gamma$-ray astronomy in the last few years has led to the discovery of more than a thousand sources at GeV energies and more than a hundred sources at TeV energies. A few different classes of compact…
Recent progress in pushing the sensitivity of the Imaging Atmospheric Cherenkov Technique into the 10 mCrab regime has enabled first sensitive observations of the innermost few 100 pc of the Milky Way in Very High Energy (VHE; >100 GeV)…
The Crab Nebula has been observed by the HEGRA stereoscopic system of 4 imaging air Cherenkov telescopes (IACTs) for about 100 hours from 1997 September to 1998 March. The recent detailed studies on the system performance give an energy…
Several key motivations and perspectives of ground based gamma-ray astronomy are discussed in the context of the specifics of detection techniques and scientific topics/objectives relevant to four major energy domains -- very-low or…
EAGLE is the multi-object, spatially-resolved, near-IR spectrograph instrument concept for the E-ELT, relying on a distributed Adaptive Optics, so-called Multi Object Adaptive Optics. This paper presents the results of a phase A study.…
We describe the instrument concept of a high angular resolution telescope dedicated to the sub-GeV (from $\gtrsim$10 MeV to $\gtrsim$1 GeV) gamma-ray photon detection. This mission, named PANGU (PAir-productioN Gamma-ray Unit), has been…
The location of the beam focus when monochromatic x-ray radiation is diffracted by a thin bent crystal is predicted by "crystal lens equation". We derive this equation in a general form valid for Bragg and Laue geometries. This equation has…
The next large NASA mission in the field of gamma-ray astronomy, GLAST, is scheduled for launch in 2007. Aside from the main instrument LAT (Large-Area Telescope), a gamma-ray telescope for the energy range between 20 MeV and > 100 GeV, a…
Adaptive optics is a technique mostly used on large telescopes. It turns out to be challenging for smaller telescopes (0.5~2m) due to the small isoplanatic angle, small subapertures and high correction speeds needed at visible wavelengths,…
Over the last decade, the Imaging Air Cerenkov technique has proven itself to be an extremely powerful means to study very energetic gamma-radiation from a number of astrophysical sources in a regime which is not practically accessible to…
In this theoretical study, the author firstly discusses the wave interference of Bragg diffraction inside 3D crystal, followed by quantum mechanical interpretation on the diffraction process, and proves that the interference fringe between…
An overview is given of high-energy gamma-ray and neutrino astronomy, emphasizing the links between the two fields. With several new large detectors just becoming operational, the TeV gamma-ray and neutrino sky will soon be surveyed with…
The Gamma-ray Large Area Space Telescope (GLAST) is a space-based observatory scheduled to launch in October 2007 with two instruments: (1) the GLAST Burst Monitor (GBM), sensitive to photon energies between 8 keV and 25 MeV and optimized…
Ground-based gamma-ray astronomy, which provides access to the TeV energy range, is a young and rapidly developing discipline. Recent discoveries in this waveband have important consequences for a wide range of topics in astrophysics and…
We discuss the ability of the GLAST Large Area Telescope (LAT) to identify, resolve, and study the high energy gamma-ray sky. Compared to previous instruments the telescope will have greatly improved sensitivity and ability to localize…
The preliminary design of the new space gamma-ray telescope GAMMA-400 for the energy range 100 MeV - 3 TeV is presented. The angular resolution of the instrument, 1-2{\deg} at E{\gamma} ~100 MeV and ~0.01^{\circ} at E{\gamma} > 100 GeV, its…
I argue that there is a crisis in optical Astronomy due to a paucity of telescopes and thus the need for a paradigm shift in telescope technology. Large increases in collecting areas and observing time/astronomer are only possible if we…