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Related papers: Stochastic modeling of x-ray superfluorescence

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Axion electrodynamics extends Maxwell's theory by postulating a hypothetical pseudoscalar axion field sourced by a scalar product of electric and magnetic fields. In this work, we demonstrate that a superposition of toroidal electromagnetic…

High Energy Physics - Phenomenology · Physics 2026-04-08 Wangke Yu , Nikitas Papasimakis , Nikolay I. Zheludev , Yijie Shen

We study a nonlinear Schr\"odinger equation which arises as an effective single particle model in X-ray Free Electron Lasers (XFEL). This equation appears as a first-principles model for the beam-matter interactions that would take place in…

Numerical Analysis · Mathematics 2014-06-18 Paolo Antonelli , Agissilaos Athanassoulis , Zhongyi Huang , Peter A. Markowich

The paper examines stochastic diffusion within an expanding space-time framework. It starts with providing a rationale for the considered model and its motivation from cosmology where the expansion of space-time is used in modelling various…

Probability · Mathematics 2023-12-22 Philip Broadbridge , Illia Donhauzer , Andriy Olenko

In this paper, we present a novel stochastic and spatially lumped multi-mode model to describe the nonlinear dynamics of actively Q-switched lasers and random perturbations due to amplified spontaneous emission. This model will serve as a…

We provide a numerical framework with which spatially and spectrally accurate representations of X-ray binary populations can be studied from hydrodynamical cosmological simulations. We construct average spectra accounting for a hot gas…

High Energy Astrophysical Phenomena · Physics 2023-01-04 Stephan Vladutescu-Zopp , Veronica Biffi , Klaus Dolag

We present a theoretical study of temporal, spectral, and spatial reshaping of intense, ultrafast x-ray pulses propagating through a resonant medium. Our calculations are based on the solution of a 3D time-dependent Schr\"odinger-Maxwell…

Atomic Physics · Physics 2020-12-30 Kai Li , Marie Labeye , Phay J. Ho , Mette B. Gaarde , Linda Young

Applying our recently-developed generalized version of the high-latitude emission theory to the observations of X-ray flares in gamma-ray bursts (GRBs), we present here clear observational evidence that the X-ray flare emission region is…

High Energy Astrophysical Phenomena · Physics 2016-06-15 Z. Lucas Uhm , Bing Zhang

We present quantum Maxwell-Bloch equations (QMBE) for spatially inhomogeneous optical semiconductor devices taking into account the quantum noise effects which cause spontaneous emission and amplified spontaneous emission. Analytical…

Quantum Physics · Physics 2007-05-23 Ortwin Hess , Holger F. Hofmann

The origin of the extended X-ray emission in the large-scale jets of active galactic nuclei (AGNs) poses challenges to conventional models of acceleration and emission. Although the electron synchrotron radiation is considered the most…

High Energy Astrophysical Phenomena · Physics 2017-06-28 Ruo-Yu Liu , F. M. Rieger , F. A. Aharonian

We review the mathematical formalism underlying the modelling of stochasticity in biological systems. Beginning with a description of the system in terms of its basic constituents, we derive the mesoscopic equations governing the dynamics…

Populations and Evolution · Quantitative Biology 2012-11-05 Alan J. McKane , Tommaso Biancalani , Tim Rogers

We study the evolution of the spectral index and the normalization (flux) of the non-thermal component of the electron spectra observed by RHESSI during 24 solar hard X-ray flares. The quantitative evolution is confronted with the…

Astrophysics · Physics 2007-05-23 Paolo C. Grigis , Arnold O. Benz

Amplified spontaneous emission is a common noise source in active optical systems, it is generally seen as being an incoherent process. Here we excite an ensemble of rare earth ion dopants in a solid with a {\pi}-pulse, resulting in…

Quantum Physics · Physics 2015-06-05 Patrick M. Ledingham , William R. Naylor , Jevon J. Longdell

We explore the stimulated emission of photons in non-spherical axion clusters with or without the axion source from the superradiance of a rotating black hole (BH). In particular, we focus on the cluster with the initial axion distribution…

High Energy Physics - Phenomenology · Physics 2024-05-31 Liang Chen , Da Huang , Chao-Qiang Geng

Most theoretical investigations of particle acceleration during solar flares cannot be applied to observations for detailed study of the time evolution. We propose a phenomenological model for turbulence evolution and stochastic particle…

Solar and Stellar Astrophysics · Physics 2009-08-10 Siming Liu , Lyndsay Fletcher

Extended X-ray emission can be studied either spatially (through its surface brightness profile) or spectrally (by analyzing the spectrum at various locations in the field). Both techniques have advantages and disadvantages, and when the…

High Energy Astrophysical Phenomena · Physics 2015-06-19 Michael E. Anderson , Joel N. Bregman

Arbitrary manipulation of the temporal and spectral properties of X-ray pulses at free-electron lasers (FELs) would revolutionize many experimental applications. At the Linac Coherent Light Source at Stanford National Accelerator…

Attosecond pulses from X-ray free-electron laser (XFEL) have opened new opportunities for probing ultrafast electronic dynamics on the Angstrom--attosecond spatiotemporal scale. Most attosecond XFEL concepts rely on generating an ultrashort…

Accelerator Physics · Physics 2026-04-22 Chenzhi Xu , Jiawei Yan , Ye Chen , Winfried Decking , Marc Guetg , Tianyun Long , Bingyang Yan , Haixiao Deng

The aim of this paper is to investigate the spatial structure of the impulsive phase hard X-ray emission from solar flares. This work is motivated by the YOHKOH and the forthcoming HESSI observations. Summarizing past results, it is shown…

Astrophysics · Physics 2009-10-31 Vahe Petrosian , Timothy Q. Donaghy

We measure the resonant forward scattering of light by a highly saturated atomic medium through the flashes emitted immediately after an abrupt extinction of the probe beam. The experiment is done in a dilute regime where the phenomena are…

Atomic Physics · Physics 2021-01-05 C. C. Kwong , T. Wellens , K. Pandey , D. Wilkowski

In this paper, one of the major shortcomings of the conventional numerical approaches is alleviated by introducing the probabilistic nature of molecular transitions into the framework of classical computational electrodynamics. The main aim…

Classical Physics · Physics 2020-01-24 Ali Reza Hashemi , Mahmood Hosseini-Farzad