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Related papers: Proton imaging of stochastic magnetic fields

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We report on the first experimental observation of a current-driven instability developing in a quasi-neutral matter-antimatter beam. Strong magnetic fields ($\geq$ 1 T) are measured, via means of a proton radiography technique, after the…

Magnetic resonance (MR) images from multiple sources often show differences in image contrast related to acquisition settings or the used scanner type. For long-term studies, longitudinal comparability is essential but can be impaired by…

Image and Video Processing · Electrical Eng. & Systems 2023-03-16 Alicia Durrer , Julia Wolleb , Florentin Bieder , Tim Sinnecker , Matthias Weigel , Robin Sandkühler , Cristina Granziera , Özgür Yaldizli , Philippe C. Cattin

We introduce a new image contrast mechanism for scanning transmission electron microscopy (STEM) that derives from the local symmetry within the specimen. For a given position of the electron probe on the specimen, the image intensity is…

Materials Science · Physics 2020-12-30 Matus Krajnak , Joanne Etheridge

Synchrotron radiation from cosmic rays is a key observational probe of the galactic magnetic field. Interpreting synchrotron emission data requires knowledge of the cosmic ray number density, which is often assumed to be in energy…

Astrophysics of Galaxies · Physics 2017-12-06 Amit Seta , Anvar Shukurov , Toby S. Wood , Paul J. Bushby , Andrew P. Snodin

We propose a method to obtain phase portraits for stochastic systems. Starting from the Fokker-Planck equation, we separate the dynamics into a convective and a diffusive part. We show that stable and unstable fixed points of the convective…

Statistical Mechanics · Physics 2018-05-03 Marc Mendler , Johannes Falk , Barbara Drossel

Electric dipole moment of the proton can be searched in an electric storage ring by measuring the spin precession rate of the proton beam on the vertical plane. In the ideal case, the spin precession comes from the coupling between the…

Accelerator Physics · Physics 2019-02-11 Selcuk Haciomeroglu , Yuri F. Orlov , Yannis K. Semertzidis

A number of aspects of magnetic force microscopy (MFM) specific to the imaging of hard magnetic films have been studied. Firstly, we show that topographic images made in tapping mode with probes characterized by the moderate cantilever…

Materials Science · Physics 2015-11-02 G Ciuta , F Dumas-Bouchiat , Nora Dempsey , Olivier Fruchart

Stochasticity effects in the spin (de)polarization of an ultrarelativistic electron beam during photon emissions in a counterpropoagating ultrastrong focused laser pulse in the quantum radiation reaction regime are investigated. We employ a…

Perfusion imaging (PI) is clinically used to assess strokes and brain tumors. Commonly used PI approaches based on magnetic resonance imaging (MRI) or computed tomography (CT) measure the effect of a contrast agent moving through blood…

Image and Video Processing · Electrical Eng. & Systems 2020-09-09 Peirong Liu , Yueh Z. Lee , Stephen R. Aylward , Marc Niethammer

We describe a technique for probing the statistical properties of cosmic magnetic fields based on radio polarimetry data. Second-order magnetic field statistics like the power spectrum cannot always distinguish between magnetic fields with…

Astrophysics of Galaxies · Physics 2015-05-13 A. Waelkens , A. A. Schekochihin , T. A. Ensslin

We consider a stochastic differential equation for a charged particle in a stochastic magnetic field, known as A-Langevin equation. The solution of the equation is found, and the Lagrange velocity correlation function is calculated in…

Chaotic Dynamics · Physics 2007-05-23 D. Lesnik , S. Gordienko , M. Neuer , K. -H. Spatschek

Stochastic acceleration of electrons and protons by waves propagating parallel to the large scale magnetic fields of magnetized plasmas is studied with emphasis on the feasibility of accelerating particles from a thermal background to…

Astrophysics · Physics 2016-08-16 Vahé Petrosian , Siming Liu

Purpose: To introduce and evaluate the use of stable distributions as a means of describing the behavior of charged particle pencil beams in a medium, with specific emphasis on proton beam scanning (PBS). Methods: The proton pencil beams of…

Medical Physics · Physics 2018-03-29 Frank Van den Heuvel , Francesca Fiorini , Niek Schreuder , Ben George

Laser-driven capacitor coils are widely used to generate intense magnetic fields for various applications in high-energy-density physics research. Accurate measurement of the magnetic fields is essential but challenging, due to the…

We consider a two-dimensional complex plasma layer containing charged dust particles in a perpendicular magnetic field. Computer simulations of both one-component and binary systems are used to explore the equilibrium particle dynamics in…

Plasma Physics · Physics 2014-03-03 T. Ott , H. Löwen , M. Bonitz

Magnetic force microscopy (MFM) allows one to image the domain structure of ferromagnetic samples by probing the dipole forces between a magnetic probe tip and a magnetic sample. The magnetic domain structure of the sample depends on the…

Instrumentation and Detectors · Physics 2014-02-24 M. Schneiderbauer , F. J. Giessibl

Piezoresponse Force Microscopy (PFM) is one of the most widespread methods for investigating and visualizing ferroelectric domain structures down to the nanometer length scale. PFM makes use of the direct coupling of the piezoelectric…

In heavy ion collisions particle distributions fluctuate from event to event. It is interesting to study local fluctuations of a specific particle specie, e.g. baryons, in the transverse plane. Fluctuations of the harmonic flow provide an…

Nuclear Theory · Physics 2026-01-16 Piotr Bozek

This work is concerned with the theoretical description of the contrast, i.e., the apparent height difference between two lateral surface positions on constant current spin-polarized scanning tunneling microscopy (SP-STM) images. We propose…

Materials Science · Physics 2013-01-25 Krisztián Palotás

Zonal flows are mean flows in the east-west direction, which are ubiquitous on planets, and can be formed through 'zonostrophic instability': within turbulence or random waves, a weak large-scale zonal flow can grow exponentially to become…

Fluid Dynamics · Physics 2024-11-20 Chen Wang , Joanne Mason , Andrew D. Gilbert