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The past decades have witnessed a lot of progress in gravitational lensing with two main targets: stars and galaxies (with active galactic nuclei). The success is partially attributed to the continuous luminescence of these sources making…

High Energy Astrophysical Phenomena · Physics 2022-11-08 Kai Liao , Marek Biesiada , Zong-Hong Zhu

Fourier optics, the principle of using Fourier Transformation to understand the functionalities of optical elements, lies at the heart of modern optics, and has been widely applied to optical information processing, imaging, holography etc.…

One of the challenges of X-ray astronomy is how to both collect large numbers of photons yet attain high angular resolution. Because X-ray telescopes utilize grazing optics, to collect more photons requires a larger acceptance angle which…

Astrophysics · Physics 2007-05-23 Craig J. Copi , Glenn D. Starkman

In recent years, our understanding of high energy density plasmas has played an important role in improving inertial fusion confinement and in emerging new fields of physics, such as laboratory astrophysics. Every new idea required…

Plasma Physics · Physics 2017-05-16 P. -A. Gourdain

X-ray free electron laser (XFEL) can provide X-ray light with about four order of magnitude higher flux than synchrotron radiation. Pulse light from XFEL interacts with the target and the resulting photons are collected by detectors. The…

Instrumentation and Detectors · Physics 2021-10-13 Shuo Zhang , Jing-Kai Xia , Xu-Dong Ju

We report on recent progress in the development of Laue lenses for applications in hard X/soft gamma-ray astronomy. Here we focus on the realization of a sector of such a lens made of 11 bent Germanium crystals and describe the…

The last decade has seen numerous efforts to achieve imaging resolution beyond that of the Abbe-Rayleigh diffraction limit. The main direction of research aiming to break this limit seeks to exploit the evanescent components containing fine…

Optics · Physics 2015-05-13 Fu Min Huang , Nikolay I. Zheludev

The number of identified Fast Radio Bursts (FRBs) is increasing rapidly with current and future facilities. Strongly lensed FRBs are expected to be found as well, which can provide precise time delays and thus have rich applications in…

High Energy Astrophysical Phenomena · Physics 2022-08-31 Xinzhong Er , Shude Mao

X-ray interferometry has the potential to provide imaging at ultra high angular resolutions of 100 micro arc seconds or better. However, designing a practical interferometer which fits within a reasonable envelope and that has sufficient…

Astrophysics · Physics 2009-11-10 R. Willingale

High precision astrometry aims at source position determination to a very small fraction of the diffraction image size, in high SNR regime. One of the key limitations to such goal is the optical response variation of the telescope over a…

Instrumentation and Methods for Astrophysics · Physics 2021-04-08 Alberto Riva , Mario Gai , Alberto Vecchiato , Deborah Busonero , Mario G. Lattanzi , Federico Landini , Zhaoxiang Qi , Zhenghong Tang

The use of strongly bent crystals in spectrometers for pulses of a hard x-ray free-electron laser is explored theoretically. Diffraction is calculated in both dynamical and kinematical theories. It is shown that diffraction can be treated…

Instrumentation and Detectors · Physics 2019-05-28 Vladimir Kaganer , Ilia Petrov , Liubov Samoylova

Although the gamma-ray emission in blazars dominates the power output, there are crucial informations carried by the X-rays. Indeed, their paucity, together with the short variability timescales observed both at X and gamma-ray energies…

Astrophysics · Physics 2007-05-23 Gabriele Ghisellini

A light ray in space is characterized by two vectors: (i) a transverse spatial-vector associated with the point where the ray intersects a given spherical cap; (ii) an angular-frequency vector which defines the ray direction of propagation.…

Optics · Physics 2023-04-10 Éric Fogret , Pierre Pellat-Finet

We propose an approach to far-field optical imaging beyond the diffraction limit. The proposed system allows image magnification, is robust with respect to material losses and can be fabricated by adapting existing metamaterial technologies…

Optics · Physics 2009-11-13 Zubin Jacob , Leonid V. Alekseyev , Evgenii Narimanov

A perfect lens with unlimited resolution has always posed a challenge to both theoretical and experimental physicists. Recent developments in optical meta-materials promise an attractive approach towards perfect lenses using negative…

Optics · Physics 2015-06-19 Jianjun Cao , Yuanlin Zheng , Yaming Feng , Xianfeng Chen , Wenjie Wan

X-ray diffraction gratings play an essential role in high-resolution spectroscopy of astrophysical phenomena. We present some scientific highlights from the X-ray grating spectrometers (XGS) on board of the Chandra and XMM/Newton missions,…

Instrumentation and Methods for Astrophysics · Physics 2024-09-05 Ralf K. Heilmann , David P. Huenemoerder , Jake A. McCoy , Randall L. McEntaffer

Macrolensing of gamma-ray bursts (GRBs) is expected to manifest as a GRB recurring with the same light curve and spectrum as a previous one, but with a different flux and a slightly offset position. Identifying such lensed GRBs may give…

High Energy Astrophysical Phenomena · Physics 2020-07-22 Björn Ahlgren , Josefin Larsson

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…

Astrophysics · Physics 2017-08-23 Jean-Paul Kneib

Gravitational lensing by clusters of galaxies affects the cosmic X-ray background (XRB) by altering the observed density and flux distribution of background X-ray sources. At faint detection flux thresholds, the resolved X-ray sources…

Astrophysics · Physics 2009-10-28 Alexandre Refregier , Abraham Loeb

We present the LAUE project devoted to develop an advanced technology for building a high focal length Laue lens for soft gamma--ray astronomy (80-600 keV). The final goal is to develop a focusing optics that can improve the current…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 E. Virgilli , F. Frontera , V. Valsan , V. Liccardo , E. Caroli , J. B. Stephen , F. Cassese , L. Recanatesi , M. Pecora , S. Mottini , P. Attiná , B. Negri
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