Holography and Coherent Diffraction Imaging with Low-(30–250 eV) and High-(80–300 keV) Energy Electrons: History, Principles, and Recent Trends

In this paper, we present the theoretical background to electron scattering in an atomic potential and the differences between low- and high-energy electrons interacting with matter. We discuss several interferometric techniques that can be realized with low- and high-energy electrons and which can be applied to the imaging of non-crystalline samples and individual macromolecules, including in-line holography, point projection microscopy, off-axis holography, and coherent diffraction imaging. The advantages of using low- and high-energy electrons for particular experiments are examined, and experimental schemes for holography and coherent diffraction imaging are compared.

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Symposium on High-Energy Electrons

10.1007/978-3-642-88334-7 ◽

1965 ◽

Cited By ~ 6

Keyword(s):

High Energy ◽

High Energy Electrons

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Properties of Elementary Particle Fluxes in Primary Cosmic Rays Measured with the Alpha Magnetic Spectrometer on the International Space Station

EPJ Web of Conferences ◽

10.1051/epjconf/201920901007 ◽

2019 ◽

Vol 209 ◽

pp. 01007

Author(s):

Francesco Nozzoli

Keyword(s):

Electron Flux ◽

Space Station ◽

Cosmic Ray ◽

High Energy ◽

Precision Measurements ◽

High Energy Electrons ◽

Electrons And Positrons ◽

Positron Flux ◽

Rigidity Dependence ◽

Alpha Magnetic Spectrometer

Precision measurements by AMS of the fluxes of cosmic ray positrons, electrons, antiprotons, protons as well as their rations reveal several unexpected and intriguing features. The presented measurements extend the energy range of the previous observations with much increased precision. The new results show that the behavior of positron flux at around 300 GeV is consistent with a new source that produce equal amount of high energy electrons and positrons. In addition, in the absolute rigidity range 60–500 GV, the antiproton, proton, and positron fluxes are found to have nearly identical rigidity dependence and the electron flux exhibits different rigidity dependence.

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Electrochemically Induced Strain Evolution in Pt–Ni Alloy Nanoparticles Observed by Bragg Coherent Diffraction Imaging

Nano Letters ◽

10.1021/acs.nanolett.1c00778 ◽

2021 ◽

Author(s):

Tomoya Kawaguchi ◽

Vladimir Komanicky ◽

Vitalii Latyshev ◽

Wonsuk Cha ◽

Evan R. Maxey ◽

...

Keyword(s):

Alloy Nanoparticles ◽

Strain Evolution ◽

Coherent Diffraction Imaging ◽

Ni Alloy ◽

Diffraction Imaging

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Complex wavefront sensing based on coherent diffraction imaging using vortex modulation

Scientific Reports ◽

10.1038/s41598-021-88523-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Rujia Li ◽

Liangcai Cao

Keyword(s):

Phase Retrieval ◽

Dynamic Range ◽

A Priori ◽

Measured Intensity ◽

Physical Constraints ◽

Coherent Diffraction Imaging ◽

Effective Dynamic ◽

Ill Posed ◽

Retrieval Problem ◽

Diffraction Imaging

AbstractPhase retrieval seeks to reconstruct the phase from the measured intensity, which is an ill-posed problem. A phase retrieval problem can be solved with physical constraints by modulating the investigated complex wavefront. Orbital angular momentum has been recently employed as a type of reliable modulation. The topological charge l is robust during propagation when there is atmospheric turbulence. In this work, topological modulation is used to solve the phase retrieval problem. Topological modulation offers an effective dynamic range of intensity constraints for reconstruction. The maximum intensity value of the spectrum is reduced by a factor of 173 under topological modulation when l is 50. The phase is iteratively reconstructed without a priori knowledge. The stagnation problem during the iteration can be avoided using multiple topological modulations.

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Polar Middle Atmospheric Responses to Medium Energy Electron (MEE) Precipitation Using Numerical Model Simulations

Atmosphere ◽

10.3390/atmos12020133 ◽

2021 ◽

Vol 12 (2) ◽

pp. 133

Author(s):

Ji-Hee Lee ◽

Geonhwa Jee ◽

Young-Sil Kwak ◽

Heejin Hwang ◽

Annika Seppälä ◽

...

Keyword(s):

Climate Model ◽

Middle Atmosphere ◽

Meridional Circulation ◽

Stratospheric Ozone ◽

High Energy ◽

Chemical Changes ◽

Temperature Changes ◽

Mesospheric Temperature ◽

High Energy Electrons ◽

Circulation Changes

Energetic particle precipitation (EPP) is known to be an important source of chemical changes in the polar middle atmosphere in winter. Recent modeling studies further suggest that chemical changes induced by EPP can also cause dynamic changes in the middle atmosphere. In this study, we investigated the atmospheric responses to the precipitation of medium-to-high energy electrons (MEEs) over the period 2005–2013 using the Specific Dynamics Whole Atmosphere Community Climate Model (SD-WACCM). Our results show that the MEE precipitation significantly increases the amounts of NOx and HOx, resulting in mesospheric and stratospheric ozone losses by up to 60% and 25% respectively during polar winter. The MEE-induced ozone loss generally increases the temperature in the lower mesosphere but decreases the temperature in the upper mesosphere with large year-to-year variability, not only by radiative effects but also by adiabatic effects. The adiabatic effects by meridional circulation changes may be dominant for the mesospheric temperature changes. In particular, the meridional circulation changes occasionally act in opposite ways to vary the temperature in terms of height variations, especially at around the solar minimum period with low geomagnetic activity, which cancels out the temperature changes to make the average small in the polar mesosphere for the 9-year period.

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The Effects of High-Energy Electrons on the Charging of Spacecraft Dielectrics

IEEE Transactions on Nuclear Science ◽

10.1109/tns.1979.4330280 ◽

1979 ◽

Vol 26 (6) ◽

pp. 5101-5106 ◽

Cited By ~ 7

Author(s):

M. J. Treadaway ◽

C. E. Mallon ◽

T. M. Flanagan ◽

R. Denson ◽

E. P. Wenaas

Keyword(s):

High Energy ◽

High Energy Electrons

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Ovaries of Chrysanthemum Irradiated with High-Energy Photons and High-Energy Electrons Can Regenerate Plants with Novel Traits

Agronomy ◽

10.3390/agronomy11061111 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1111

Author(s):

Natalia Miler ◽

Iwona Jedrzejczyk ◽

Seweryn Jakubowski ◽

Janusz Winiecki

Keyword(s):

Total Dose ◽

In Vitro Regeneration ◽

High Energy ◽

Mutation Breeding ◽

Chrysanthemum Morifolium ◽

Physical Factors ◽

Strong Impact ◽

Breeding Method ◽

High Energy Electrons

Classical mutation breeding using physical factors is a common breeding method for ornamental crops. The aim of our study was to examine the utility of ovaries excised from irradiated inflorescences of Chrysanthemum × morifolium (Ramat.) as explants for breeding purposes. We studied the in vitro regeneration capacity of the ovaries of two chrysanthemum cultivars: ‘Profesor Jerzy’ and ‘Karolina’ preceded by irradiation with high-energy photons (total dose 5, 10 and 15 Gy) and high-energy electrons (total dose 10 Gy). Growth and inflorescence parameters of greenhouse acclimatized regenerants were recorded, and ploidy level was estimated with flow cytometry. The strong impact of genotype on regeneration efficiency was recorded—cultivar ‘Karolina’ produced only 7 viable shoots, while ‘Profesor Jerzy’ produced totally 428 shoots. With an increase of irradiation dose, the regeneration decreased, the least responsive were explants irradiated with 15 Gy high-energy photons and 10 Gy high-energy electrons. Regenerants of ‘Profesor Jerzy’ obtained from these explants possessed shorter stem and flowered later. The highest number of stable, color and shape inflorescence variations were obtained from explants treated with 10 Gy high-energy photons. Variations of inflorescences were predominantly changes of shape—from full to semi-full. New color phenotypes were dark yellow, light yellow and pinkish, among them only the dark yellow phenotype remained stable during second year cultivation. None of the regenerants were haploid. The application of ovaries irradiated within the whole inflorescence of chrysanthemum can be successfully applied in the breeding programs, provided the mother cultivar regenerate in vitro efficiently.

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