Exploring new regimes, optimizing experimental setups, or quantifying sensitivity of final beam parameters on experimental parameters, represent current challenges for simulations of laser plasma accelerators. Time-to-solution and scalability are key parameters for codes to minimize turnaround times in order to scan e.g. tens of parameters such as the laser leading edge, resolve solid density...

The hybrid L|PWFA acceleration scheme combines laser- (LWFA) with plasma-wakefield acceleration (PWFA) to provide an ultra-compact, high-brightness electron source. Recently, the acceleration of a witness bunch using this hybrid scheme was demonstrated at HZDR. In this talk, we present recent start-to-end simulations, that accompanied the experimental campaign, and provided fundamental...

Modelling the complex dynamics in plasma accelerators requires computationally demanding Particle-In-Cell codes. These codes self-consistently solve the electromagnetic particle interaction inside the plasma. We present the latest features of FBPIC - a highly efficient, multi-GPU Particle-In-Cell code. It features a quasi-3D geometry that greatly reduces the computational costs, a spectral...

Particle-in-Cell (PIC) codes have proven to be a vital tool for studying the physics of plasma based accelerators. However, the enormous cost of a single full 3D simulation limits their applicability for extensive stability or parameter studies. Further, numerical errors from commonly used finite difference solvers can cause unphysical results. The quasi-cylindrical, pseudo-spectral code FBPIC...

Smilei is an open-source particle-in-cell (PIC) simulation code. It is developed by a collaboration of scientific computing experts and plasma physicists for applications ranging from astrophysics to laser-plasma interactions. In order to address this large variety of scientific cases, Smilei gathers many different features in a single software suit and adopts flexible data structures and...

The advent of ultra short high intensity lasers has paved the way to new and promising, yet challenging, areas of research in the laser-plasma interaction physics. The success of constructing petawatt femtosecond lasers, that helps designing future particle accelerators, intrinsically relies on the combination between experiments and massively parallel simulations. Hitherto, Particle-In-Cell...

Three dimensional Particle in Cell simulations of Laser Wakefield Acceleration require a considerable amount of resources but are necessary to have realistic predictions and to design future experiments. The planned experiments for the CILEX facility also include two stages of plasma acceleration, for a total plasma length of the order of centimiters. In this context, where traditional 3D...

One of the most challenging application of plasma accelerators is the development of a plasma-based collider for high-energy physics studies. Fast and accurate simulation tools are essential to study the physics toward configurations that enable the production and acceleration of very small beams with low energy spread and emittance preservation over long distances, as required for a collider....

Vorpal was designed nearly 20 years ago, with its first applications roughly four years later, as a highly performant, flexible plasma simulation code. Using object oriented methods, Vorpal was designed to allow runtime selection from multiple field solvers, particle dynamics, and reactions. It has been successful in modeling for many areas of accelerator physics, including RF structures,...

QuickPIC is a 3D parallel quasi-static PIC code for efficiently simulating the plasma based accelerator (PBA). It is developed based on the framework UPIC. QuickPIC has been widely used and played an important role in studying PBA problems. In 2017, we made QuickPIC an open source code on Github (https://github.com/UCLA-Plasma-Simulation-Group/QuickPIC-OpenSource). The open source QuickPIC was...

If a charged particle bunch propagates near a plasma-vacuum boundary, it experiences an additional force caused by the boundary. Taking account of this force may be important for witness injection into plasma wakefields or in case of beam and plasma misalignments. For the linearly responding plasma and short and narrow bunch, this force is calculated analytically and approximated by elementary...

Next generation accelerators demand sophisticated beam sources to produce ultra-low emittances with large gradients. The subsequent beamline optics are equally critical to transporting these beams between accelerating stages or to interaction points. Capillary discharge plasmas may address each of these challenges. Capillaries have been demonstrated as sources capable of increasing the peak...

A simplified model describing the PWFA transverse instability in the form of a wake function parameterized only with an effective cavity aperture radius $a$ is benchmarked against QuickPIC simulations. This wake function implies a $1/a^4$ scaling of the transverse wakefields, which indicates transverse intra-beam wakefields typically several orders of magnitude higher than in conventional...

Laser-driven electrostatic shocks have shown the potential to accelerate ions to very high energy with low energy spread and divergence and thus, they constitute a very promising ion acceleration mechanism [1,2,3]. Leveraging multi-dimensional realistic particle-in-cell simulations, this work explores how intense shocks can be excited in near-critical and underdense plasma targets. The...

A new multi-dimensional solver for Maxwell equations will be presented. It rips the volumetric Yee lattice to a transverse plane. The fields locations become Lorentz-invariant. The solver alleviates numerical dispersion for plane waves running along the selected axis and perfectly fits for problems of particle acceleration in plasmas. The solver has a compact local stencil and allows for...

Photoionization by a femtosecond TW laser pulse generates a plasma column in a neutral ambient gas.The 3D laser wake wave extends through the column surface, generating an azimuthally polarized rotational current within a micron-thin shell. This current supports a broad-band, evanescent THz signal accompanying the wake, detectable at a distance orders of magnitude larger than the column...