Hydrodynamic plasma waveguides initiated by optical field ionization (OFI) have recently become a key component of multi-GeV laser wakefield accelerators [1–4], We present comprehensive experimental and simulation-based characterization, applicable both to current multi-GeV experiments and future 100 GeV-scale laser plasma accelerators. Crucial to the simulations is the correct modeling of...
Designs for linear colliders based on laser wakefield acceleration (LWFA) must address dephasing, which occurs when trapped particles outpace the accelerating phase of the wakefield. To address dephasing, current designs employ many stages, each operating at a low plasma density, which limits the acceleration gradient and elongates both the individual stages and total collider length. Here, we...
Kinetic simulations of relativistic, charged particle beams and advanced plasma accelerator elements are often performed with high-fidelity particle-in-cell simulations, some of which fill the largest GPU supercomputers. Self-consistent modeling of wakefield accelerators for colliders includes many elements beyond plasma acceleration. The integrated Beam, Plasma & Accelerator Simulation...
The advanced accelerator community increasingly recognizes the importance of extending high peak- and average-power laser facilities to longer wavelengths. This recognition is driven by the lambda-squared scaling of the ponderomotive force, inverse-lambda-squared scaling of critical plasma density, and linear-lambda scaling of the number of photons per joule of energy. A significant potential...
Given a very short and intense plane-wave laser pulse travelling in the positive $z$ direction, we propose a multi-step preliminary analytical procedure to tailor the initial density profile $\widetilde{n_0}(z)$ of a cold diluted collisionless plasma to the pulse, so as to control the formation of the plasma wave (PW), its wave-breaking (WB) at density inhomogeneities, the self-injection of...
Compact laser plasma accelerators running at repetition rates >1 kHz promise a wide range of applications in science research, medicine, and security. Commercially available laser systems operating at kHz repetition rates offer mJ pulses with pulse duration as low as tens fs. To fulfill the resonant condition for the laser wakefield acceleration, temporal compression of these pulses is...
We report self-injecting LWFA driven by CPA-CO2 laser pulses of wavelength ~10 micrometers at Brookhaven's Accelerator Test Facility [1]. Long-wave IR pulses open opportunities to drive large wakes in low-density plasma more efficiently than near-IR pulses, potentially enabling higher-quality accelerated bunches. In experiments, 0.5-TW, 4-ps laser pulses generated no electrons, but drove...
“Flying focus” techniques produce laser pulses with dynamic focal points that can travel distances much greater than a Rayleigh length. The implementation of these techniques in laser-based applications requires the design of optical configurations that can both extend the focal range and structure the radial group delay. This work describes a method for designing optical configurations that...
We report on electron-beam collimation using a passive plasma lens[1], integrated directly into a laser wakefield-accelerator stage operating in the high-charge regime. The lens is created by the reshaping of the gas-density profile of a supersonic jet at the beam’s exit side. It reduces the beam’s divergence by a factor of 2 to below 1 mrad (rms), while preserving the total charge of 170 pC...
Laser wakefield acceleration (LWFA) using laser-ablated metallic plasma targets has been developed for high-vacuum and high-repetition rate operations. The metallic plasma density (called the pre-plasma) generated by laser-ablation is increased via the optical ionization process due to intense fs laser pulse (called the main laser). The optical guiding of main laser in the plasma is influenced...
Recently developed techniques for optical generation of low density (≤10^17 cm^(-3)), meter-scale hydrodynamic plasma waveguides in extended supersonic gas jets [1-3] have already enabled a new class of fully-optical multi-GeV laser wakefield accelerators [4,5]. Optimization of the laser wakefield acceleration (LWFA) process in these types of waveguides and plans for future, single-stage 100...
A tunable laser positron source as originally described in [1] is being prototyped using the collocated LWIR CO2 laser and electron beam at BNL-ATF. Unlike LPA, this work deals with interaction of three distinct entities, a laser, a pair-plasma, and laser-driven electron density structures.
This work relies on the advantages of larger size of electron density structures excited by the CO2...