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Related papers: Superradiant parametric X-ray emission

200 papers

We consider the radiation from an electron in flight over a surface wave of an arbitrary profile excited in a plane interface. For an electron bunch the conditions are specified under which the overall radiation essentially exceeds the…

Accelerator Physics · Physics 2011-01-24 A. A. Saharian

Based on kinematic model of parametric X-ray Radiation (PXR), an approach for calculation of PXR characteristics (spectrum, intensity, polarization and yield) has been developed. The approach allows to take into account the beam divergence,…

Strongly Correlated Electrons · Physics 2016-08-31 A. P. Potylitsin

We compute the hard X-ray spectra from a hot plasma pervaded by small cold dense clouds. The main cooling mechanism of the plasma is Compton cooling by the soft thermal emission from the clouds. We compute numerically the equilibrium…

Astrophysics · Physics 2009-11-07 Julien Malzac , Annalisa Celotti

Pulsars emit low-frequency radio waves through to high-energy gamma-rays that are generated anywhere from the surface out to the edges of the magnetosphere. Detecting correlated mode changes in the multi-wavelength emission is therefore key…

Serial femtosecond X-ray crystallography (SFX) captures the structure and dynamics of biological macromolecules at high spatial and temporal resolutions. The ultrashort pulse produced by an X-ray free electron laser (XFEL) 'outruns' much of…

Plasma Physics · Physics 2025-06-03 Spencer K. Passmore , Alaric L. Sanders , Andrew V. Martin , Harry M. Quiney

In the fallback disk model for the persistent emission of Anomalous X-ray pulsars (AXPs) and soft gamma-ray repeaters (SGRs), the hard X-ray emission arises from bulk- and thermal Comptonization of bremsstrahlung photons, which are…

High Energy Astrophysical Phenomena · Physics 2015-06-18 N. D. Kylafis , J. E. Truemper , U. Ertan

The spectrum of laser-plasma generated X-rays is very important, it characterizes electron dynamics in plasma and is basic for applications. However, the accuracies and efficiencies of existing methods to diagnose the spectrum of…

Instrumentation and Detectors · Physics 2021-09-03 Jiaxing Wen , Minghai Yu , Yuchi Wu , Ming Zeng , Bo Zhang , Jirong Cang , Yuge Zhang , Ge Ma , Yue Yang , Wenbo Mo , Zongqing Zhao

Accretion-powered X-ray pulsars are among the most luminous X-ray sources in the Galaxy. However, despite decades of theoretical and observational work since their discovery, no satisfactory model for the formation of the observed X-ray…

Astrophysics · Physics 2009-11-11 Peter A. Becker , Michael T. Wolff

Fresnel theory is used to derive the complex electric-fields above and below an X-ray reflecting interface that separates two materials with differing indices of refraction. The interference between the incident and reflected waves produces…

Materials Science · Physics 2009-08-17 Michael J. Bedzyk

We present here an analysis of the X-ray properties of a sample of LINER galaxies observed with the ROSAT PSPC and HRI instruments. A spatial analysis shows that the bulk of the X-ray emission is consistent with arising from a point source;…

Although the surface of a magnetar is a source of bright thermal X-rays, its spectrum contains substantial non-thermal components. The X-ray emission is pulsed, with pulsed fractions that can be as high as ~ 70%. Several properties of…

Astrophysics · Physics 2011-02-11 Rodrigo Fernandez , Christopher Thompson

X-ray scattering spectra of Cu and Ni metals have been measured using monochromatic synchrotron radiation tuned from far above to more than 10 eV below threshold. Energy conservation in the scattering process is found to be sufficient to…

Materials Science · Physics 2012-01-04 M. Magnuson , J. -E. Rubensson , A. Föhlisch , N. Wassdahl , A. Nilsson , N. Mårtensson

Using a quantum electrodynamic framework, we calculate the off-resonant scattering of a broad-band X-ray pulse from a sample initially prepared in an arbitrary superposition of electronic states. The signal consists of single-particle…

Chemical Physics · Physics 2015-06-19 Kochise Bennett , Jason D. Biggs , Yu Zhang , Konstantin E. Dorfman , Shaul Mukamel

We describe a new method to produce intensity stable, highly coherent, narrow-band x-ray pulses in self-seeded free electron (FEL) lasers. The approach uses an ultra-short electron beam to generate a single spike FEL pulse with a wide…

Accelerator Physics · Physics 2020-07-29 Erik Hemsing , Aliaksei Halavanau , Zhen Zhang

We study a phenomenological model for the continuum emission of Seyfert galaxies. In this quasi-spherical accretion scenario, the central X-ray source is constituted by a hot spherical plasma region surrounded by spherically distributed…

Astrophysics · Physics 2016-08-30 Julien Malzac

When a high-contrast ultra-relativistic laser beam enters a micro-sized plasma waveguide, the pulse energy is coupled into waveguide modes, which remarkably modifies the interaction of electrons and electromagnetic wave. The electrons that…

Plasma Physics · Physics 2016-08-03 Longqing Yi , Alexander Pukhov , Baifei Shen

High-brightness femtosecond-to-attosecond pulses are indispensable for probing electron dynamics on their fundamental temporal scales. X-ray free-electron lasers (XFELs) at high repetition rates will facilitate high-statistics measurements…

Accelerator Physics · Physics 2026-05-01 Junhao Liu , Zhen Wang , Lanpeng Ni , Yujie Lu , Chao Feng , Zhentang Zhao

At modern X-ray sources, such as synchrotrons and X-ray Free-Electron Lasers (XFELs), it is important to measure the absolute value of the photon energy directly. Here, a method for absolute spectral metrology is presented. A photon energy…

The aim of this paper is to try to explain the physical origin of the non-thermal electron distribution that is able to form the enhanced intensities of satellite lines in the X-ray line spectra observed during the impulsive phases of some…

Solar and Stellar Astrophysics · Physics 2017-07-05 Elena Dzifcakova , Marek Vandas , Marian Karlicky