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Recent advances in successful operation of silicon-based devices where transport is dependent on electron magnetic moment, or "spin", could provide a future alternative to CMOS for logic processing. The basics of this spin electronics (Spintronics) technology are discussed and the specific methods necessary for application to silicon are described. Fundamental measurements of spin polarization and spin precession are demonstrated.

A review is presented of recent results in QCD from the H1 and ZEUS experiments at HERA, emphasizing the use of higher order calculations to describe the data.

It is well known that an electron has either spin-up or spin-down state and a photon has two possible polarizations called spin $+1$ or spin $-1$. But when two particles are created, the two particles can have 50% of one state and 50% in the other. This is called the two particles in quantum entanglement. The spooky thing is that an event at one point in the universe can instantaneously affect the event that is arbitrarily far away between these two particles.^a The entanglement of the two particles can be electron or photon. We believe, in order to study this phenomenon we have to study further than the previously established principles of quantum mechanics, that is, to study how an electron creates a photon and how it interacts with the photon emitted.

Quantum entanglement simplified-video results — Quantum entanglement and spooky action at a distance, youtube.com, two years ago.

We propose the idea of method for observing the effect of the Earth’s gravitational field on the motion of an electron. Earlier attempts to measure such an effect proved unsuccessful due to the fact that under the conductive sheath, the gravitational force acting on the non-relativistic electron is completely compensated by Barnhill–Schiff force. Therefore, experiments of this kind were unable to measure the effect of the Earth’s gravitational field on the motion of electrons. In this paper, we propose to use electrons moving with relativistic speeds in the horizontal plane, and with non-relativistic speeds in the vertical direction, in which case the gravitational force on these electrons is not fully compensated by the Barnhill–Schiff force. Calculations showed that in this case, it is possible to measure the force exerted on an electron by the gravitational field of the Earth.

We have proposed the semi-empirical formula for pair production cross-section in nuclear and electric field of atoms with atomic number $1\le Z\le 100$ in the energy range of $1\mathrm{\text{MeV}}\le E\le 100\mathrm{\text{GeV}}$. To validate the present formula, the values produced by the proposed formula are compared with the available experiments. The percentage of deviation of present formula pair production was found to be less than $\pm 2\%$. The present formula is useful in the fields of radiation, particle and Nuclear Physics.

The Alpha Magnetic Spectrometer is a particle physics detector focusing on the search for dark matter, the existence of antimatter, the origin and composition of cosmic rays from primordial sources in the universe and the exploration of new physics in space. Important features of the elementary particle (proton, antiproton, positron and election) fluxes in cosmic rays are presented: (1) The proton spectrum has a smooth hardening from 200 GeV; (2) antiproton and positron spectra show excess from traditional physics background; (3) in particular, the positron flux shows a source term with a cutoff energy of 810 GeV, which raises the question of its source; (4) the origin of the energetic electrons is different from that of positrons and (5) the identical momentum dependence of primary and secondary cosmic ray nuclei fluxes are also reviewed.

Results of study of secondary electrons and positrons in the energy range 15–150 MeV in the earth space-orbit are reviewed.

The spectral distribution of positron created by photon and the spectral distribution of photons radiated from electron in an oriented single crystal of intermediate thickness is calculated at intermediate energies. The energy loss of charged particles as well as photon absorption are taken into account. The used basic probabilities of processes include the action of field of axis as well as the multiple scattering of radiating electron or particles of the created pair (the Landau-Pomeranchuk-Migdal (LPM) effect).

Measurable parameters of the electron indicate that its background should be described by the Kerr–Newman (KN) solution. The spin/mass ratio of the electron is extreme large and the black hole (BH) horizons disappear, opening a topological defect of space–time — the Kerr singular ring of Compton size, which may be interpreted as a closed fundamental string to low-energy string theory. The singular and two-sheeted structure of the corresponding Kerr space has to be regularized, and we consider the old problem of regularizing the source of the KN solution. As a development of the earlier Keres–Israel–Hamity–López model, we describe the model of smooth and regular source forming a gravitating and relativistically rotating soliton based on the chiral field model and the Higgs mechanism of broken symmetry. The model reveals some new remarkable properties: (1) the soliton forms a relativistically rotating bubble of Compton radius, which is filled by the oscillating Higgs field in a pseudo-vacuum state; (2) the boundary of the bubble forms a domain wall which interpolates between the internal flat background and the external exact KN solution; (3) the phase transition is provided by a system of chiral fields; (4) the vector potential of the external KN solution forms a closed Wilson loop which is quantized, giving rise to a quantized spin of the soliton and (5) the soliton is bordered by a closed string, which is a part of the general complex stringy structure.

Electron and photon triggers are an important part of many physics analyses at the ATLAS experiment, where electron and photon final states are considered. Understanding the performance of electron and photon triggers at the High Level trigger as well as the Level-1 trigger was crucial to improve and adapt the trigger during changing run conditions of the Large Hadron Collider in Run 2 (2015–2018).

In direct dark matter (DM) detection via scattering off the electrons, the momentum transfer plays a crucial role. Previous work showed that for self-interacting DM, if the DM particle has a size (the so-called puffy DM), the radius effect could dominate the momentum transfer and become another source of velocity dependence for self-scattering cross-section. In this work, we investigate the direct detection of puffy DM particles with different radii through electron recoil. We find that comparing with the available experimental exclusion limits dominated by the mediator effect for XENON10, XENON100 and XENON1T, the constraints on the puffy DM-electron scattering cross-section become much weaker for large radius DM particles. For small-radius DM particles, the constraints remain similar to the point-like DM case.

In the development of most phenomenological models used to explain the infrared excited luminescence, a major assumption is usually made in the degree of freedom the excited charge has. One of the two extremes is normally assumed: charge is free to move anywhere over the whole crystal, or it is confined close to the trap and the centers immediately adjacent to it. Determining which of these extremes is more reasonable is difficult to do on the basis of the temporal behavior of the luminescence intensity alone. However, this assumption has important consequences for the understanding of the dynamics of the luminescence process because of the difference in the number of recombination and trapping centers available to the excited charge. Additional experimental evidence was thus sought on this aspect of charge movement. One such experiment is the detection of photoconductivity in which an electrical current is measured during optical excitation or shortly there-after. In this paper, the details of photoconductivity experiments on K crystal are presented.

Photoconductivity measurements were inconclusive as to whether or not there was a current flowing during the 850 nm excitation of a feldspar sample. However, there was a clear current when exciting the same sample with 515 nm light, but there was a complex relationship between the magnitude of the current and the number of emission photons counted. A model was developed to explain the photoconductivity results where electrons migrate through the conduction band aided by thermal excitation and tunneling.

The development of an analytical model for calculating the electron stopping power (SP) converging with the experimental data at lower energies is still not completed. The purpose of this work is to suggest a mathematical expression of the range and the stopping power of electrons impinging in solid targets in the energy range up to 30 keV based on the spherical geometric model [A. Bentabet, Vacuum86 (2012) 1855]. The results are in good agreement with those of the literature. The slight discrepancy between the obtained and both the theoretical and experimental results regarding the stopping power at very low energy (E<0.5 keV) is discussed.

In view of difficulties and questions of quantum mechanics in description of motion of electrons in hydrogen atom, we here established their nonlinear theory of motion based on the true motions of electron and nucleon and the real interactions between them, in which the motion of electron is depicted by a nonlinear Schrödinger equation with a Coulomb potential, the nonlinear interaction b∣φ∣²φ is produced by the change of Coulomb interaction between nucleon and electron due to the motion of nucleon. Thus the natures of the electron are thoroughly changed relative to those in quantum mechanics due to the nonlinear interactions, it not only is stable and localized, but also possesses a wave–corpuscle duality. Meanwhile, if its eigenenergy is still quantized and distributed in accordance with the energy levels, then we can use the new theory to explain perfectly the spectrum features of hydrogen atom, which resembles quantum mechanics, but its sizes of eigenenergy are depressed relative to that in quantum mechanics. This means that the nonlinear interaction enhances the localized and stable nature of the electron. Therefore, the new nonlinear theory is successful and correct to the hydrogen atom.

A well-known mystery in quantum mechanics is wave–particle duality: Is an electron a point mass or a physical wave? What is the physical meaning of its wave function? About a hundred years ago, there was a famous debate between Bohr and Einstein on this topic. Their question is still open today. This paper reviews a new theoretical framework to address this problem. Here, it is hypothesized that both photons and electrons are quantized excitation waves of the vacuum, the physical properties of which can be modeled based on the Maxwell theory. Using the method of Helmholtz decomposition, one can show that the wave function of the particle is associated with an electric vector potential called “ Z”, which plays the role of basic field for the excitation wave. Using this framework, the quantum wave equations can be derived based on a quantization of the Maxwell theory. This work suggests that, the quantum wave function truly represents a physical wave; the wave packet looks like a “particle” only in the macroscopic view. Because the vacuum excitation obeys the principle of all-or-none, the probability of detecting this “particle” is related to the wave function as suggested in the Copenhagen interpretation.

Investigating the dark matter (DM) properties in the view of cosmic evolution is an important method in searching for DM. In this paper, we derive the modified Boltzmann equations and study how the elastic scattering between the DM particles and the free electrons in our universe influences the CMB and matter power spectra starting from a few basic assumptions. The results indicates that the scattering affects the small scales significantly, especially the CMB polarization power spectra. With this method, the coupling constant between DM and electrons can be constrained with CMB observational data and the results only depend on a few basic assumptions.

In this paper, we refer to the early hypotheses on superconductivity in the models of the electron as an extended particle, and show how Nonlinear Electrodynamics minimally coupled to Gravity (NED-GR) predicts, without additional assumptions, the existence of primary superconductivity as the universal property of regular electrically charged rotating black holes and electromagnetic spinning solitons, replacing naked singularities and including that with the parameters of the electron. NED-GR dynamical equations describe basic generic properties of these objects in a self-consistent and the model-independent way, and establish the existence of the superconducting ring current in their deep interiors, which presents the non-dissipative source of the electromagnetic field of an object and provides its practically unlimited life time.

The positron–electron fluxes detected by AMS02, CALET, DAMPE and Fermi-LAT have shown their complex structure which deviated from a single power-law, and the results of DAMPE and Fermi-LAT are obviously higher than those of AMS02 and CALET in 100GeV–1TeV range. We point out that the complex positron–electron flux structures can be attributed to two sources with a natural background, and the difference between the two groups of data can be explained in an anomalous bremsstrahlung theory.

The physics motivation, accelerator science, plans for future facilities and major accelerator systems of electron–ion colliders are presented. The science enabled by these machines motivates the machine design with high luminosity and flexibility, and thus leads to new challenges in accelerator science. Innovative solutions, developed in order to achieve the objectives set for these machines, are described. Major accelerator systems and accelerator physics issues are also described, and references are provided for readers interested in greater detail.

Particle accelerators are the ultimate microscopes. They produce high energy beams of particles — or, in some cases, generate X-ray laser pulses — to probe the fundamental particles and forces that make up the universe and to explore the building blocks of life. But it takes huge accelerators, like the Large Hadron Collider or the two-mile-long SLAC linac, to generate beams with enough energy and resolving power. If we could achieve the same thing with accelerators just a few meters long, accelerators and particle colliders could be much smaller and cheaper. Since the first theoretical work in the early 1980s, an exciting series of experiments have aimed at accelerating electrons and positrons to high energies in a much shorter distance by having them “surf” on waves of hot, ionized gas like that found in fluorescent light tubes. Electron-beam-driven experiments have measured the integrated and dynamic aspects of plasma focusing, the bright flux of high energy betatron radiation photons, particle beam refraction at the plasma–neutral-gas interface, and the structure and amplitude of the accelerating wakefield. Gradients spanning kT/m to MT/m for focusing and 100MeV/m to 50GeV/m for acceleration have been excited in meter-long plasmas with densities of 10${}^{14}$–10${}^{17}$cm${}^{-3}$, respectively. Positron-beam-driven experiments have evidenced the more complex dynamic and integrated plasma focusing, 100MeV/m to 5GeV/m acceleration in linear and nonlinear plasma waves, and explored the dynamics of hollow channel plasma structures. Strongly beam-loaded plasma waves have accelerated beams of electrons and positrons with hundreds of pC of charge to over 5GeV in meter scale plasmas with high efficiency and narrow energy spread. These “plasma wakefield acceleration” experiments have been mounted by a diverse group of accelerator, laser and plasma researchers from national laboratories and universities around the world. This article reviews the basic principles of plasma wakefield acceleration with electron and positron beams, the current state of understanding, the push for first applications and the long range R&D roadmap toward a high energy collider.