arXiv subjects

Jesús E. López

Publications and source records attributed to Jesús E. López.

5 recordsLinked to original sources

arXiv2026

KEMPIC-3D: A transparent and extensible electromagnetic Particle-in-Cell framework for kinetic plasma simulations

KEMPIC-3D, a fully electromagnetic three-dimensional particle-in-cell (PIC) code, has been developed in C/C++ and systematically verified for the self-consistent simulation of kinetic plasma phenomena. The numerical framework combines a staggered Yee finite-difference time-domain solver for Maxwell's equations with a relativistic Boris particle pusher, trilinear field interpolation, and charge-conserving current deposition. Its modular architecture emphasizes algorithmic transparency and extensibility, allowing the principal numerical routines to be directly inspected and modified to incorporate additional physical models and computational capabilities. The implementation is assessed through a hierarchy of benchmark problems addressing both the individual numerical components and the self-consistent particle--field coupling. The particle pusher is verified against analytical solutions for relativistic charged-particle motion, while the electromagnetic field solver is evaluated through guided-wave propagation and grid-convergence analysis. The complete PIC algorithm is subsequently verified through plasma oscillations, global energy conservation, and discrete charge continuity, demonstrating the numerical accuracy, conservation properties, and self-consistency of the coupled formulation. The capabilities of KEMPIC-3D are further demonstrated through a representative simulation of laser-driven plasma wakefield generation in an underdense plasma. The simulations reproduce the characteristic nonlinear wakefield structure and exhibit stable numerical behavior across different particle discretizations without additional spatial filtering. Together, these results establish KEMPIC-3D as a reliable, transparent, and extensible computational framework for multidimensional kinetic plasma simulations.

physics.plasm-ph↗

arXiv2026

Numerical study of electron acceleration by microwave-driven plasma wakefields in rectangular waveguides

Plasma-based acceleration schemes have attracted sustained interest as a pathway toward compact particle accelerators, owing to the large electric fields supported by plasmas. Although recent studies have demonstrated the excitation of plasma wakefields using high-power microwave pulses in plasma-filled waveguides, the conditions required for efficient electron acceleration in such configurations remain insufficiently characterized. In this work, we investigate the acceleration of externally injected electrons by microwave-driven plasma wakefields in rectangular waveguides filled with low-density plasma. Three-dimensional particle-in-cell simulations are employed to analyze the dynamics of electron injection and energy gain under both reduced and fully self-consistent numerical models. The results show that electron acceleration is strongly dependent on the injection phase and initial velocity. Optimal acceleration is achieved when electrons are pre-accelerated to velocities close to the group velocity of the driving microwave pulse. For the parameters considered, energy gains of the order of $10^2 \mathrm{keV}$ are obtained over interaction lengths of the order of meters, while maintaining a quasi-monoenergetic energy distribution under suitable injection conditions. The influence of transverse dynamics and space-charge effects is also examined, revealing additional constraints on acceleration efficiency associated with the transverse electromagnetic field of the driving microwave pulse. These results provide a quantitative assessment of the acceleration stage in microwave-driven plasma wakefield schemes and support their evaluation as a viable platform for compact plasma-based accelerators.

physics.plasm-ph↗

arXiv2025

Design and Numerical Simulation of a SARA-Based RF Accelerator Using the $\mathrm{TE}_{112}$ Mode

Charged particle accelerators play a pivotal role in scientific research, industry, and medical applications. Among them, radiofrequency (RF) accelerators offer a promising approach for achieving high-energy particle acceleration in compact systems. This study presents the design and numerical simulation of a microwave-driven electron accelerator based on the Spatial Autoresonant Acceleration (SARA) mechanism. The proposed system consists of a cylindrical resonant cavity excited in the TE$_{112}$ mode, influenced by a tailored magnetostatic field generated by a set of external coils. The electromagnetic field distribution, magnetostatic configuration, and electron dynamics were simulated using COMSOL Multiphysics. The results validate the feasibility of accelerating electrons to energies close to 200~keV with a 1~kW microwave source, demonstrating their capability for X-ray generation through Bremsstrahlung radiation. Additionally, the study provides optimized design parameters for practical implementation. The high-quality factor $(Q\sim25000)$ of the resonant cavity ensures efficient energy storage but necessitates precise frequency control to maintain resonance conditions. The findings underscore the potential of SARA-based accelerators for compact X-ray sources, with applications in medical imaging, security screening, and materials analysis.

physics.acc-ph↗

arXiv2025

Particle-in-cell simulations of plasma wakefield formation in microwave waveguides

The acceleration of charged particles is fundamental not only for experimental studies in particle physics but also for applications in fields such as semiconductor manufacturing and medical therapies. However, conventional accelerators face limitations due to their large size, driven by low acceleration gradients. Plasma-based accelerators have emerged as a promising alternative, offering ultrahigh acceleration gradients, though their implementation is often limited by the need for high-intensity, femtosecond laser systems and sophisticated diagnostics. As a more accessible alternative, the use of microwave pulses to excite plasma wakefields in waveguides filled with low-density plasma has gained attention. In this study, we perform three-dimensional particle-in-cell simulations to investigate the formation and structure of electrostatic wakefields driven by short microwave pulses in rectangular plasma waveguides. The results establish a theoretical basis for evaluating the feasibility and potential applications of microwave-driven plasma acceleration schemes.

physics.plasm-ph↗

arXiv2025

Electron Acceleration by the Axisymmetric TE$_{011}$ Mode in a Slowly Varying External Magnetic Field

This study investigates the autoresonant acceleration of electrons using the GYRAC mechanism in a cylindrical cavity excited in the TE$_{011}$ microwave mode, under a slowly increasing external magnetic field. The acceleration process is driven by the interaction between electrons and the right-hand circularly polarized (RHP) component of the electric field, maintained in phase through electron cyclotron resonance (ECR). A simplified single-particle model and numerical simulations based on the relativistic Newton-Lorentz equation were employed to evaluate particle dynamics under different values of the magnetic field growth parameter $ α$. The results demonstrate that efficient trapping and energy transfer can be achieved for appropriate values of $ α$, and that the spatial non-uniformity of the TE$_{011}$ mode introduces critical sensitivity to initial particle positioning. The study further identifies a ring-shaped region in which electrons are consistently captured in the GYRAC regime, and shows how the evolution of the Larmor radius, phase shift, and energy distribution depends on the electromagnetic configuration. Simulations involving disk-like and ring-like electron clouds reveal the fraction of captured, escaped, and uncaptured particles, confirming that precise control of the magnetic field variation is essential to optimize the efficiency of the acceleration process. These findings provide a basis for future self-consistent plasma simulations and support the development of compact radiation sources based on GYRAC-TE$_{011}$ acceleration.

physics.acc-ph↗