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Related papers: Beam focusing and consequences for Doppler Backsca…

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Turbulent plasma edge density fluctuations can broaden a traversing microwave beam degrading its quality. This can be a problem for scenarios relying on a high spatial localization of the deposition of injected microwave power, like…

A wave near an isolated turning point is typically assumed to have an Airy function profile with respect to the separation distance. This description is incomplete, however, and is insufficient to describe the behavior of more realistic…

Plasma Physics · Physics 2023-05-17 N. A. Lopez , E. Kur , D. J. Strozzi

All prior applications of Diffusing-Wave Spectroscopy (DWS) to aqueous foams rely upon the assumption that the electric field of the detected light is a Gaussian random variable and that, hence, the Siegert relation applies. Here we test…

Soft Condensed Matter · Physics 2009-11-11 A. S. Gittings , D. J. Durian

Extreme scattering events (ESEs) are observed as dramatic ($>50\%$) drops in flux density that occur over an extended period of weeks to months. Discrete plasma lensing structures are theorized to scatter the radio waves produced by distant…

Astrophysics of Galaxies · Physics 2024-01-19 Kelvin Au , Jason D. Fiege , Adam Rogers

Plasma turbulence, and edge density fluctuations in particular, can under certain conditions broaden the cross-section of injected microwave beams significantly. This can be a severe problem for applications relying on well-localized…

It is not fully understood how electromagnetic waves propagate through plasma density fluctuations when the size of the fluctuations is comparable with the wavelength of the incident radiation. In this paper, the perturbing effect of a…

Plasma Physics · Physics 2016-09-21 Alf Köhn , Eberhard Holzhauer , Jarrod Leddy , Matthew B Thomas , Roddy G L Vann

Optical beams propagating through air acquire phase distortions from turbulent fluctuations in the refractive index. While these distortions are usually deleterious to propagation, beams reflected in a turbulent medium can undergo a local…

Optics · Physics 2023-07-19 W. Nelson , J. P. Palastro , C. Wu , C. C. Davis

We investigate the properties of the optical model wave function for light heavy-ion systems where absorption is incomplete, such as $\alpha + ^{40}$Ca and $\alpha + ^{16}$O around 30 MeV incident energy. Strong focusing effects are…

Nuclear Theory · Physics 2008-11-26 F. Brau , F. Michel , G. Reidemeister

The scattering of light observed through the turbid underwater channel is often regarded as the leading challenge when designing underwater electro-optical imaging systems. There have been many approaches to address the effects of…

Optics · Physics 2018-04-17 Chensheng Wu , Robert Lee , Christopher C. Davis

We report the observation of two additional sub-natural line width quantum interference in the $D_2$ manifold of $^{39}K$ vapor, in addition to the usual single Electromagnetically induced transparency peak. The other two features appear…

Atomic Physics · Physics 2024-03-28 Gourab Pal , Subhasish Dutta Gupta , Saptarishi Chaudhuri

The scattering of polarized light incident from one dielectric medium on its two-dimensional randomly rough interface with a second dielectric medium is studied. A reduced Rayleigh equation for the scattering amplitudes is derived for the…

A new Doppler backscattering (DBS) system, consisting of Q-band and V-band, has been installed and achieved its first data on the MAST-U spherical tokamak. The Q-band and V-band have separate microwave source systems, but share the same…

Plasma Physics · Physics 2023-09-12 P. Shi , R. Scannell , J. Wen , Z. B. Shi , C. Michael , T. Rhodes , V. H. Hall-Chen , Z. C. Yang , M. Jiang , W. L. Zhong

We revisit the description of inverse Compton scattering sources and the photon beams generated therein, emphasizing the behavior of their phase space density distributions and how they depend upon those of the two colliding beams of…

Accelerator Physics · Physics 2017-09-13 C. Curatolo , I. Drebot , V. Petrillo , L. Serafini

Diffusing Wave Spectroscopy (DWS) is an extension of standard dynamic light scattering (DLS), applied to soft materials that are turbid or opaque. The propagation of light is modeled using light diffusion, characterized by a light diffusion…

Soft Condensed Matter · Physics 2025-12-15 Manuel Helfer , Chi Zhang , Frank Scheffold

In this paper, an analytical theory for the diffraction of a Bessel beam of arbitrary order $J_l(\kappa r)$ on a 2D amplitude grating is presented. The diffraction pattern in the main and fractional Talbot planes under certain conditions is…

Optics · Physics 2020-06-24 I. A. Kotelnikov , O. E. Kameshkov , B. A. Knyazev

Plasma scattering measurement is effective technique to observe low frequency density fluctuations excited in plasma. The spatial and wave number resolutions and the S/N ratio of measurement depend on the wavelength range, the size and the…

{We study biasing as a physical phenomenon by analysing geometrical and clustering properties of density fields of matter and galaxies.} {Our goal is to determine the bias function using a combination of geometrical and power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-25 J. Einasto , L. J. Liivamägi , I. Suhhonenko , M. Einasto

We demonstrate numerically a method of focusing two-photon field inside one-dimensional random media. The approach is based on coherent control of backscattering achieved by adaptive spectral pulse shaping. The spectral phases of a…

Optics · Physics 2016-03-02 Alex C. Han , Valery Milner

The possibility of focusing light to an ever tighter spot has important implications for many applications and fields of optics research, such as nano-optics and plasmonics, laser-scanning microscopy, optical data storage and many more. The…

This paper presents an analytical analysis of the Doppler spectrum in von Mises-Fisher (vMF) scattering channels. A simple closed-form expression for the Doppler spectrum is derived and used to investigate the impact of the vMF scattering…

Signal Processing · Electrical Eng. & Systems 2025-01-30 Kenan Turbic , Martin Kasparick , Slawomir Stanczak