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In this paper, electron acceleration by relativistic pondermotive force has been studied in the interaction of intense laser pulse with an axially inhomogeneous underdense plasma. The results show that the relativistic ponderomotive nonlinearity causes obvious beam self-focusing and a highly energetic electron can be achieved in the plasma, moreover, the high-energy electron would be automatically ejected by the ponderomotive force without adding any additional extractor. In addition, it is found that the real part and imaginary part of Lorentz factor can directly affect the amplitude and change the trend of electron acceleration, and electrons acceleration can be strengthened when we can elect properly the laser intensity with higher momentum and smaller beam width, but nonuniformity of plasmas can slightly decrease the electron acceleration. The results can provide useful physical support for novel design of table accelerator and the optimized parameters of electron acceleration in the plasma. [ABSTRACT FROM AUTHOR]

To the best of our knowledge, for the first time, the quantum Hall effect (QHE) is considered in thermal non-equilibrium conditions (TNEC) via q -algebra. The q -algebra is a topological tool that provides a controlling q -parameter to approximate theoretical results to the laboratory ones. We obtain the QHE spectrum and q -deformed Hall potential (or Hall potential in TNEC) via the density probability current. Because of the Pauli Exclusion Principle, we model the QHE using relativistic Fermi electron gas and the q -deformed Fermi–Dirac distribution. We find the dependence of deformed Hall potential to temperature and magnetic field for different geometric q -regions. Further, we geometrically prove that the magnitude of the Hall potentials depends on the q -regions (i.e. | V H (q > 1) | > | V H (q = 1) | > | V H (q < 1) |). We find that for some q -amounts, the Landau energy gap on graphene-based materials can be explained in the room-temperature quantum Hall effect (RTQHE). Our method may be applied to analyze new electronic devices based on graphene in TNEQ. [ABSTRACT FROM AUTHOR]

In this work, we explore a generalization of the Dirac and Klein–Gordon (KG) oscillators, provided with a deformed linear momentum inspired in nonextensive statistics, that gives place to the Morse potential in relativistic contexts by first principles. In the (1 + 1)-dimensional case, the relativistic oscillators are mapped into the quantum Morse potential. Using the Pekeris approximation, in the (3 + 1)-dimensional case, we study the thermodynamics of the S-waves states (l = 0) of the H2, LiH, HCl and CO molecules (in the non-relativistic limit) and of a relativistic electron, where Schottky anomalies (due to the finiteness of the Morse spectrum) and spin contributions to the heat capacity are reported. By revisiting a generalized Pekeris approximation, we provide a mapping from (3 + 1)-dimensional Dirac and KG equations with a spherical potential to an associated one-dimensional Schrödinger-like equation, and we obtain the family of potentials for which this mapping corresponds to a Schrödinger equation with non-minimal coupling. [ABSTRACT FROM AUTHOR]

The contemporary theoretical investigation researches the resonant emission of high-energy gamma-quanta within the process of scattering of ultrarelativistic electrons on a nucleus in the external electromagnetic field. With implementation of the resonant conditions under the field ambience the particle in the intermediate state re-modulates into the real form. Therefore, the phenomenon examination determines the functional splitting of the second order process into a pair of first-order effects that possess a possibility to develop within two reaction channels. Consequently, the first channel characterizes the kinematics of electron scattering by a nucleus and following radiation of a spontaneous gamma-quantum. The second channel delineates the spontaneous gamma-quantum radiation by an electron with subsequent scattering on a nucleus. It is important to emphasize that within a specific range of observation the calculations derive three discrete magnitudes for the resonant frequency dependency on the angle of spontaneous photon radiation. As a result, the work represents an estimation of the resonant differential scattering cross-section in ratio to the scattering cross-section computed without the external field. In conclusion, various scientific facilities may verify the project data simulation (SLAC, FAIR, XFEL, ELI, XCELS). [ABSTRACT FROM AUTHOR]

On the basis of the one-particle Dirac equation, an exact solution for the problem of the energy spectrum of a relativistic electron on the surface of a tube in a magnetic field is obtained. The spectra of a relativistic rotator and a relativistic electron in a two-dimensional electron gas are obtained in limiting cases. The density of electron states and the main thermodynamic functions of a relativistic electron gas on a tube in a magnetic field are calculated. These values experience Aharonov–Bohm oscillations and oscillations of the de Haas–van Alphen type with a change of the magnetic field and parameters of the problem. The asymptotics of thermodynamic functions at low- and high-temperatures are obtained. The results can be used in studies of nanotubes of a two-dimensional electron gas and in astrophysics. [ABSTRACT FROM AUTHOR]

The studies of strong field particle physics processes in electron/laser interactions and lepton collider interaction points (IPs) are reviewed. These processes are defined by the high intensity of the electromagnetic fields involved and the need to take them into account as fully as possible. Thus, the main theoretical framework considered is the Furry interaction picture within intense field quantum field theory. In this framework, the influence of a background electromagnetic field in the Lagrangian is calculated nonperturbatively, involving exact solutions for quantized charged particles in the background field. These 'dressed' particles go on to interact perturbatively with other particles, enabling the background field to play both macroscopic and microscopic roles. Macroscopically, the background field starts to polarize the vacuum, in effect rendering it a dispersive medium. Particles encountering this dispersive vacuum obtain a lifetime, either radiating or decaying into pair particles at a rate dependent on the intensity of the background field. In fact, the intensity of the background field enters into the coupling constant of the strong field quantum electrodynamic Lagrangian, influencing all particle processes. A number of new phenomena occur. Particles gain an intensity-dependent rest mass shift that accounts for their presence in the dispersive vacuum. Multi-photon events involving more than one external field photon occur at each vertex. Higher order processes which exchange a virtual strong field particle resonate via the lifetimes of the unstable strong field states. Two main arenas of strong field physics are reviewed; those occurring in relativistic electron interactions with intense laser beams, and those occurring in the beam-beam physics at the interaction point of colliders. This review outlines the theory, describes its significant novel phenomenology and details the experimental schema required to detect strong field effects and the simulation programs required to model them. [ABSTRACT FROM AUTHOR]

Edge effects in spectra of non-dipole radiation from ultra-relativistic electrons passing through various finite targets are analyzed from a unified point of view. Examples include radiation in a finite magnet, bremsstrahlung at double scattering, and bremsstrahlung in an amorphous plate. A generalization of the encountered spectral decomposition property is proposed. The relevance of phenomena of jet-inter-jet radiation interference and electron time delay in the target is emphasized. Features produced by them in the radiation spectra are discussed. [ABSTRACT FROM AUTHOR]

The influence of the noncommutativity on the average speed of a relativistic electron interacting with a uniform magnetic field within the minimum evolution time is investigated. We find that it is possible for the wave packet of the electron to travel faster than the speed of light in vacuum because of the noncommutativity. It is a clear signature of violating Lorentz invariance in the noncommutative relativistic quantum mechanical region. [ABSTRACT FROM AUTHOR]

It is recognized that very likely the correlation between peak energy and bolometric intensity is intrinsic to GRBs. However, its physical origin is still debated. In this paper, we will discuss a possible interpretation of the correlation in the light of a GRB prompt emission spectral model, grbcomp, proposed in [L. Titarchuk, R. Farinelli, F. Frontera and L. Amati, Astrophys. J. 752 (2012) 116]. grbcomp is essentially a photospheric model for the prompt emission of GRBs. Its main ingredients are a thermal bath of soft seed photons and a subrelativistically expanding outflow plasma, consequence of the star explosion. The emerging spectrum is the result of two phases: first, up to the photospheric radius, Comptonization of a subrelativistic electron outflow with thermal bath of soft photons, then, convolution of the Comptonized photons in the first phase with a Green function. The result of this convolution is consistent with different physical processes, in particular Inverse Compton. grbcomp has been successfully tested using a significant sample of GRB time resolved spectra in the broad energy band from 2keV to 2MeV [F. Frontera, L. Amati, R. Farinelli, S. Dichiara, C. Guidorzi, R. Landi and L. Titarchuk, Astrophys. J. 779 (2013) 175]. [ABSTRACT FROM AUTHOR]

Based on the basic definition of the Fermi energy of degenerate and relativistic electrons, we obtain a special solution to the electron Fermi energy, , and express as a function of the electron fraction, , and matter density, . We obtain several useful analytical formula for and within classical models and the work of Dutra et al. (2014) (Type-2) in relativistic mean-field theory are obtained using numerically fitting. When describing the mean-field Lagrangian, density, we adopt the TMA parameter set, which is remarkably consistent with the updated astrophysical observations of neutron stars (NSs). Due to the importance of the density dependence of the symmetry energy, , in nuclear astrophysics, a brief discussion on and its slop is presented. Combining these fitting formula with boundary conditions for different density regions, we can evaluate the value of in any given matter density, and obtain a schematic diagram of as a continuous function of . Compared with previous studies on the electron Fermi energy in other studies models, our methods of calculating are more simple and convenient, and can be universally suitable for the relativistic electron regions in the circumstances of common neutron stars. We have deduced a general expression of and , which could be used to indirectly test whether one equation of state of a NS is correct in our future studies on neutron star matter properties. Since URCA reactions are expected in the center of a massive star due to high-value electron Fermi energy and electron fraction, this study could be useful in the future studies on the NS thermal evolution. [ABSTRACT FROM AUTHOR]

According to the usual application of the sequential-suppression picture to the dynamics of heavy quarkonia in the hot medium formed in ultrarelativistic nuclear collisions, quark-antiquark pairs created in a given bound or unbound state remain in that same state as the medium evolves. We argue that this scenario implicitly assumes an adiabatic evolution of the quarkonia and we show that the validity of the adiabaticity assumption is questionable. [ABSTRACT FROM AUTHOR]

Magnetic susceptibility of the quark and electron gas is calculated in a closed form for any chemical potential μ summing the whole Matsubara series. For the quark gas and small μ≪T a strong rise with T is found due to Polyakov loop factors L(T), in good agreement with lattice data. For the electron gas the lowest Matsubara term (n = 1) contributes 40% larger than the exact answer. In the case of small T, , the oscillations as functions of eB occur, characteristic of the de Haas-van Alphen effect. Results are compared with available lattice data and with the case of relativistic electron gas, which obtains putting L(T)≡1. [ABSTRACT FROM AUTHOR]

Based on our previous work, we deduce a general formula for pressure of degenerate and relativistic electrons, Pe, which is suitable for superhigh magnetic fields, discuss the quantization of Landau levels of electrons, and consider the quantum electrodynamic (QED) effects on the equations of states (EOSs) for different matter systems. The main conclusions are as follows: Pe is related to the magnetic field B, matter density ρ, and electron fraction Ye; the stronger the magnetic field, the higher the electron pressure becomes; the high electron pressure could be caused by high Fermi energy of electrons in a superhigh magnetic field; compared with a common radio pulsar, a magnetar could be a more compact oblate spheroid-like deformed neutron star (NS) due to the anisotropic total pressure; and an increase in the maximum mass of a magnetar is expected because of the positive contribution of the magnetic field energy to the EOS of the star. [ABSTRACT FROM AUTHOR]

By applying a method of virtual quanta we derive formulae for relativistic non-thermal bremsstrahlung radiation from relativistic electrons as well as from protons and heavier particles with power-law momentum distribution N(p)dp = k p-qdp. We show that emission which originates from an electron scattering on an ion, represents the most significant component of relativistic non-thermal bremsstrahlung. Radiation from an ion scattering on electron, known as inverse bremsstrahlung, is shown to be negligible in overall non-thermal bremsstrahlung emission. These results arise from theory refinement, where we introduce the dependence of relativistic kinetic energy of an incident particle, upon the energy of scattered photon. In part, it is also a consequence of a different mass of particles and relativistic effects. [ABSTRACT FROM AUTHOR]