Conveners
WG3: Theory and simulations
- Andrea Renato Rossi (Istituto Nazionale di Fisica Nucleare)
- Maxence Thevenet (Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany)
WG3: Theory and simulations
- Maxence Thevenet (Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany)
- Andrea Renato Rossi (Istituto Nazionale di Fisica Nucleare)
We present an energy-conserving theory of plasma wakefield in the strongly-nonlinear (“bubble” or “blowout”) regime. Previous phenomenological models [W. Lu et al. PRL 96, 165002 (2006)] were based on using the electron motion equations in plasma and assumptions about the electron sheath on the bubble's boundary. However, they often included fitting parameters and, in general, provided an...
After the introduction of high-quality electron beam generation methods as two-color [1] or the Resonant Multi Pulse Ionization injection (ReMPI) [2], the theory of thermal emittance by C. Schroeder et al. [3] has been used to predict the beam normalized emittance obtainable with those schemes. We [4] recast and extend such a theory, including both higher order terms in the polinomial laser...
In this talk, we present a new and efficient methodology for the simulation of fluid models in the framework of wakefield acceleration (WFA). This technique hinges on the Lattice Boltzmann Method (LBM), a popular numerical scheme used in several contexts of computational fluid dynamics and beyond, and couples it with a finite difference time domain for the solution of electromagnetic fields....
One of the key effects in laser wakefield acceleration is dephasing, whereby the electron beam outruns the accelerating structure created by the sub-luminal driving laser pulse. This process reduces the effectiveness of the accelerator and limits the maximum electron energy achievable with a given laser pulse. Therefore, mitigating dephasing is important in maximising the energy gain and...
To enable the generation of high-quality electron beams from laser plasma accelerators, understanding and tailoring of plasma sources is of critical importance. With limited experimental setups and measurement options, hydrodynamic simulations can be used to study their ns- to ms-evolution in detail and evaluate new concepts.
In recent years, hydrodynamic optical-field-ionized (HOFI)...
We consider a relativistic witness electron bunch propagating in an ionized gas background of opposite charge, a simplified configuration similar to the one produced in a capillary discharge where a plasma oscillation has been excited by a driving pulse. We assume in the nonlinear regime, the plasma electrons behind the driver are completely expelled and an ellipsoidal cavity filled with ions...
While simulations of plasma acceleration are becoming affordable, specific problems remain hard to model. This is the case for collider-relevant parameters (high energy, low emittance beam), long beams (as seen for example in the AWAKE experiment) or positron acceleration, where scale discrepancies call for impractical number of grid cells. In this work, we present numerical methods to reduce...
Computational modeling is essential to the exploration and design of advanced particle accelerators. The modeling of laser-plasma acceleration and interaction can achieve predictive quality for experiments if adequate resolution, full geometry and physical effects are included. Here, we report on the significant evolution in fully relativistic full-3D modeling of conventional and advanced...
Dielectric Wakefield Acceleration (DWA) is a promising technology with potential applications in future accelerators. To facilitate DWA research and experimentation, we have developed Dielectric Wakefield Calculator and Tracker (DiWaCAT), a versatile python and C++ based code. DiWaCAT enables rapid and accurate 3D wakefield calculations in circular and planar dielectric-lined waveguides (DLWs)...
The electromagnetic Particle-In-Cell (PIC) code WarpX has been developed within the the U.S. Department of Energy’s Exascale Computing Project toward the modeling of plasma accelerators for future high-energy physics colliders on Exascale Supercomputers. We will present the latest algorithmic advances that were developed for first-principles modeling of plasma-based accelerators with higher...
Plasma wakefield accelerators offer exceptional gradients, enabling compact accelerators. Using a density downramp injection scheme, ultra-short electron bunches with sub-micron emittance and tens of pico-Coulombs of charge can be generated and promptly accelerated. While these beam parameters are of utmost interest for future compact X-ray sources and other imaging techniques, the viability...
The demonstration of a multi-stage scheme is one of the milestones to make laser wakefield acceleration (LWFA) a scalable acceleration mechanism to reach high energies. The design of such complex scheme will require advanced multi physics modeling of the different components of the machine and integrating data-driven approaches into the exploration of the parameter space of interest.
A...
Exascale computing has recently become a reality. PIConGPU has paved the way to accelerating plasma simulations across compute platforms using the Alpaka framework. These capabilities not only enables conducting high-fidelity parameter scans of start-to-end simulations modeling experiments at full 3D3V geometry, but also make it possible to include additional physics.
However, experience...
