Next-generation accelerators, such as those employing plasma or laser wakefield acceleration techniques, demand precise characterization of the beam's properties, making accurate measurement of the five-dimensional (5D) phase space distribution essential. To meet this need, a novel transverse deflecting structure with adjustable polarization, known as the Polarizable X-band Transverse...
The staging of laser-driven plasma accelerators (LPAs) could open up energy frontiers, but achieving in- and out-coupling of laser pulses while preserving beam quality remains a challenge. In this work, we present an all-optical, in-plasma staging scheme that uses refraction in a transverse plasma density gradient to couple the incoming laser into the next LPA stage, eliminating the need for...
Plasma wakefield acceleration is a method that uses a driving particle beam or an intense laser to excite a wakefield in the plasma and uses the wakefield to accelerate another bunch of particles. In response to the need to simulate the plasma wakefield acceleration, large-scale parallel computing programs such as QuickPIC [1] and QPAD [2] have been developed. These programs use the...
In this work, we investigate the energy transfer from a long proton bunch driver to the plasma in the context of the AWAKE experiment, using particle-in-cell simulations with OSIRIS. As the driver propagates through the plasma, it excites wakefields by displacing plasma electrons, which gain kinetic energy. This energy can dissipate through several mechanisms, including electromagnetic...
Laser WakeField Acceleration (LWFA) is a useful mechanism for generating secondary radiation in a compact accelerator setup. Different types of radiation can be produced by the relativistic electrons accelerated in this process. Betatron X-ray radiation is emitted by the electrons due to their transverse oscillations in the plasma channel, while THz radiation is emitted when the electrons...
Laser WakeField Acceleration (LWFA) is a useful mechanism for generating secondary radiation in a compact accelerator setup. Different types of radiation can be produced by the relativistic electrons accelerated in this process. Betatron X-ray radiation is emitted by the electrons due to their transverse oscillations in the plasma channel, while THz radiation is emitted when the electrons...
The driving laser's spectrum evolves during laser-wakefield acceleration due to the density and intensity gradients in the driven plasma wave. These density gradients also determine the accelerating fields experienced by injected electrons, and so the post-acceleration laser spectrum may be correlated with the electron spectrum, potentially allowing for its use as a non-disruptive diagnostic...
Curved plasma waveguides have been proposed as a means to: guide fresh laser pulses into multistage plasma accelerators [1, 2], replace plasma mirror tapes used to eject depleted laser pulses [3], and to bend electron bunches for radiation generation [4-6]. However, all curved channel experiments so far have employed discharge capillaries, which are prone to laser damage especially at high...
Ultra-short laser pulses are essential to resolve femtosecond-timescale dynamics in plasma-based particle accelerators. Presented here is a high-intensity hollow-core beam line designed to spectrally broaden an input spectrum by a factor three, with an output pulse energy of ~2 mJ. These pulses can then be compressed to ~10 fs and will be utilized to take crisp shadowgrams of plasma wave...
Recent all-optical multi-GeV laser wakefield acceleration (LWFA) demonstrations have been enabled by University of Maryland's development of meter-scale supersonic gas jets and low-density plasma waveguides. This poster presents a review of our recent LWFA efforts, including gas jet development, experiments and simulations to benchmark plasma waveguide generation, a new 3-stage model for...
The Advanced Wakefield Experiment (AWAKE) at CERN uses CERN SPS bunches to develop proton-driven plasma wakefield acceleration. However, to excite ~GV/m wakefields, the long SPS bunches must undergo self-modulation (SM) in plasma. SM is a beam-plasma instability and the instability can be seeded to ensure wakefield reproducibility. During Run 2a (2021–2022), AWAKE demonstrated SM seeding using...
Electron-positron plasmas are fundamental to understanding some of the most energetic astrophysical phenomena and represent a unique state of matter. While they have been theoretically studied extensively, experimental studies remain limited due to the challenge of generating and confining such plasmas.
Numerous setups have been proposed to maximize pair yield [1]. With the advent of...
The quality of electron beams produced by Laser Wakefield Acceleration (LWFA), is controlled through laser parameters and plasma density distribution during the injection and acceleration phases, and in some cases, a specific device providing beam selection or shaping to achieve the electron beam quality needed the envisaged application.
A major challenge in the generation of LWFA...
In the high-power laser-matter interaction, two main components are the laser pulse and the target. By adjusting one of them, the results can be tailored to a specific application. Nano and micro structured targets are being studied for applications of high intensity laser-matter interaction for more than 30 years and take many forms: gratings, wires, dots, spheres, tubes. With the help of...
Charged particles moving through carbon nanostructures may excite electromagnetic modes (plasmonic modes) due to the collective excitation of the electron gas in their surfaces. This effect might be a potential candidate to accelerate particles with ultra-high accelerating gradients. The plasmonic excitations can be studied by particle simulations and with analytical models. In this...
A long, narrow bunch propagating in plasma is subject to the self-modulation (SM) instability, a transverse process. In the AWAKE experiment, we study the evolution of SM along the plasma by changing the length of plasma over which the bunch propagates. In particular, we observe the effect of the transverse wakefields on the bunch by measuring the size of the halo of defocused particles at a...
Simulations play a key role in the design of plasma sources, employed for plasma-based accelerators and other applications, and it is important to have alternative codes, for simulating the dynamics of the plasma. We propose an open source code, PLUTO, which allows to perform 3D, hydrodynamic (HD) and magneto-hydrodynamic (MHD) simulations of gas-filled plasma discharge capillaries. We...
Particle-in-cell (PIC) simulations are a well-established tool to study and predict the outcomes of a Laser Plasma Accelerator experiment, but the results are often hindered by the initialization of highly idealized laser profiles. In this work, we present the development of a Laser Pulse reconstructor For Particle In Cell simulations (LP4PIC), a Python package to retrieve...
Laser-driven plasma accelerators offer a compact, cost-effective alternative to conventional radiofrequency accelerators, capable of generating very high energy and ultra-high dose-rate radiation sources that induce unique cellular responses. We report on the characterisation of laser-driven, very high energy electrons and the response of seven in vitro cell lines to this radiation source. ...
The development of scalable plasma sources is essential for future plasma wakefield acceleration (PWFA) applications. In this work, we present a pulsed-DC Discharge Plasma Source (DPS) developed for the AWAKE experiment at CERN, which requires a highly uniform electron density of $7×10^{14}$ cm$^{−3}$ maintained over tens to hundreds of meters. This DPS has already demonstrated to be...
Plasma wakefield acceleration (PWFA) offers acceleration gradients much larger than that in conventional accelerators. The Full Energy Beam Exploitation (FEBE), a new beamline attached to the Compact Linear Accelerator for Research and Applications (CLARA) at Daresbury Laboratory, has been designed as a dedicated test facility for users. By providing access to high-power lasers and electron...
Microbunching instability (MBI) remains a critical challenge for high-brightness electron beams in linear accelerators, especially for free electron lasers (FEL). We present a comprehensive study of the MBI in the context of EuPRAXIA@SPARC_LAB, the first FEL user facility driven by plasma acceleration, focusing on both the emergence and the mitigation of MBI under various machine...
Relativistic electrons colliding with an intense laser pulse will produce scattered photons through the non-linear Compton scattering (NLCS) process. Self-guided multi-GeV electrons that are accelerated in a gas jet interact at a small collision angle with the self-reflecting intense laser pulse. We describe recent PW-class experiments using a self-reflecting scheme to generate a bright and...
One important application of laser wakefield acceleration is the production of bright x-ray beams generated from the betatron oscillations of electrons in the wake of a laser pulse. The amplitude of the betatron oscillations is directly correlated with key characteristics of the emitted x-ray radiation, such as flux, critical energy, and divergence. We experimentally demonstrate that a shock...
All-optical high-energy X-ray (HEX) beam sources based on Inverse Compton Scattering (ICS) are a promising and innovative alternative to conventional sources, enabling the generation of X-ray beams with percent-level bandwidth. These X-rays are generated by colliding a laser pulse with relativistic electron beams from a laser-plasma accelerator. Although a low HEX bandwidth is essential for...
Laser Wakefield Accelerators (LWFA) offer a promising solution for producing high-energy electron beams in compact setups. Beyond obtaining the required energy, the beam quality (emittance, energy spread, intensity) must also be optimized for LWFA to be considered an alternative to conventional accelerators. Achieving precise control of the transverse beam dynamics is one of the key...
Nuclear fusion represents one of the most promising and at the same time challenging pathways toward a sustainable and reliable energy production. A novel inertial fusion concept proposes the use of nanostructured targets in the form of arrays of thin rods that are irradiated by high-intensity laser pulses. The resulting rapid electron expulsion triggers a Coulomb explosion that accelerates...
A wakefield experiment at the Argonne Wakefield Accelerator (AWA) facility utilizes flat electron beams with highly asymmetric transverse emittances to drive plasma wakefields in the underdense regime. These beams create elliptical blowout structures, producing asymmetric transverse focusing forces. The experiment utilizes a compact 4-cm-long capillary discharge plasma source developed at...
Laser-plasma ion acceleration is a well established field of research, with several mechanisms being exploited to produce high energy, short particle beams.
Scaling laws show that both the laser's vector potential, and the critical density scale favorably with laser wavelength. Hence the long wavelength ($\mathrm{9.2\mu m}$) $\mathrm{CO_{2}}$ laser at the Brookhaven National Laboratories...
Laser-electron accelerators emerge as novel, compact sources of high-quality relativistic electron beams. Their extremely high peak currents make them ideal for applications in fields such as material science, healthcare, and particle physics.
Each experimental application requires unique electron parameters. Additionally, all the input parameters are interconnected, resulting in a highly...
The quality of electron beams generated by laser wakefield accelerators (LWFAs) is constantly improving to the point where it is now possible to operate novel light sources such as free-electron lasers (FELs), as has been achieved at various facilities. However, this method is still limited by the fluctuations of the electron beam properties, which are difficult to control due to the...
