Nanostructures are currently attracting attention as a medium for obtaining ultra-high-density plasmas for beam-driven or laser-driven acceleration. This study investigates Bayesian optimization in Laser Wakefield Acceleration (LWFA) to enhance solid-state plasma parameters towards achieving extremely high gradients on the order of TV/m or beyond, specifically focusing on nanostructured plasmas based on arrays of carbon nanotubes. Through Particle-In-Cell (PIC) simulations via EPOCH and custom Python scripts, we conducted a parameter analysis for various configurations of carbon nanotube arrays. Utilizing the open-source machine learning library BoTorch for optimization, our work resulted in a detailed database of simulation results. This enabled us to pinpoint optimal parameters for generating effective wakefields in these specialized plasmas. Ultimately, the results demonstrate that Bayesian optimization is an excellent tool for significantly refining parameter selection for nanostructures like carbon nanotube arrays, thus enabling the design of promising nanostructures for LWFA.

Monochromatization of the beams is presented as a technique to reduce the energy spread and thus improve the CM energy resolution in colliding-beam experiments. Monochromatization consists of generating opposite correlations between a spatial position and the energy deviation in the colliding beams. In beam-optics terms, this can be achieved by generating a nonzero dispersion function of opposite signs for the two beams at the Interaction Points. For the FCC-ee collider monochomatization could enable measurement of the electron Yukawa coupling. This talk will describe the different possible implementation schemes in a high-energy collider as FCC-ee, including the impact of beamstrahlung, and future possible experimental tests at current running colliders.

The 2023 Particle Physics Project Prioritization Panel recommends an updated approach for accelerator R&D activities in the US research program. Key recommendations for the DOE-HEP General Accelerator R&D Program, a new targeted Collider R&D program, and the potential for increased engagement with the NSF are described.

The Fermilab Accelerator Science and Technology (FAST) facility is dedicated to the exploration of novel concepts in accelerator and beam physics, and the development of a robust workforce, in order to enable and enhance next-generation particle accelerators. FAST comprises a high-brightness superconducting electron linac, and a storage ring, the Integrable Optics Test Accelerator (IOTA). Experiments in the most recent operational run include studies of nonlinear integrable lattices; tracking of single electrons; precise characterization of undulator radiation; studies with low-momentum-compaction lattices; and ultra-wide range beam diagnostics based on Photomultiplier tubes. In the linac, experiments on noise in intense electron bunches were conducted. The IOTA proton injector, currently being commissioned, will enable a diverse program on space-charge-dominated beams. Research areas include non-invasive beam profile monitoring for proton beams; beam dynamics with electron lenses; halo suppression, feedback systems, and electron cooling. In this presentation, we provide an overview of the recent results and highlight future plans together with opportunities for collaboration.

Nanostructures are currently attracting attention as a medium for obtaining ultra-high-density plasmas for beam-driven or laser-driven acceleration. This study investigates Bayesian optimization in Laser Wakefield Acceleration (LWFA) to enhance solid-state plasma parameters towards achieving extremely high gradients on the order of TV/m or beyond, specifically focusing on nanostructured plasmas based on arrays of carbon nanotubes. Through Particle-In-Cell (PIC) simulations via EPOCH and custom Python scripts, we conducted a parameter analysis for various configurations of carbon nanotube arrays. Utilizing the open-source machine learning library BoTorch for optimization, our work resulted in a detailed database of simulation results. This enabled us to pinpoint optimal parameters for generating effective wakefields in these specialized plasmas. Ultimately, the results demonstrate that Bayesian optimization is an excellent tool for significantly refining parameter selection for nanostructures like carbon nanotube arrays, thus enabling the design of promising nanostructures for LWFA.

A very high electron peak current is needed in many applications of modern electron accelerators. To achieve this high current, a large energy chirp must be imposed on the bunch so that the electrons will compress when they pass through a chicane. In existing linear accelerators (LINACs), this energy chirp is imposed by accelerating the beam off-crest from the peak fields of the RF cavities, which increases the total length and power requirements of the LINAC. A novel concept known as the Transverse Deflecting Cavity Based Chirper (TCBC) [1] can be used to actively impose a large energy chirp onto an electron beam in an accelerator, without the need for off-crest acceleration. The TCBC consists of 3 transverse deflecting cavities, which together impose an energy chirp while cancelling out the transverse deflection. An experiment is being developed to demonstrate this concept at the Argonne Wakefield Accelerator (AWA) facility. Here we explain the concept, show preliminary simulations of the experiment, and report on progress related to implementation of the experiment at AWA.

A novel deuteron accelerator concept, the deuteron cyclotron auto-resonance accelerator (dCARA) is presented here, with (a) an analytical theory to characterize a simplified model for dCARA, (b) simulated tracks of deuteron orbits in a more realistic model for dCARA, and (c) CST-Studio particle-in-cell simulations for high-current deuteron beams in a realistic dCARA. These predict that dCARA will produce a high-current multi-MeV beam of accelerated deuterons along an axis parallel to, but displaced from, the center conductor of a coaxial resonator immersed in a uniform static magnetic field. The example presented, where the magnetic field strength is 7.0 T (for cyclotron auto-resonance at 53.0 MHz), acceleration of a 100 mA deuteron beam from 60 keV to 35 MeV is predicted to occur along a 2.8 m long half-wave resonant cavity, with an efficiency of 88%. Such a beam could be highly competitive with that produced either with linacs or cyclotrons for an application to produce, via deuteron stripping, a high flux of neutrons with an energy spectrum centered near 14.1 MeV, as needed for testing inner-wall materials for a future deuterium-tritium fusion power reactor.

I plan to discuss potential offered by Energy-Recovery Linacs (ERLs) and particle recycling for boosting luminosity in high-energy electron-positions and lepton-hadron colliders. ERL-based colliders have promise not only of significantly higher luminosity, but also of higher energy efficiency measured in units of luminosity divided by the consumed AC power. Addition of recycling collided particles and their recuperations in damping ring removes insane ILC/CLIC appetite for fresh positions and offers high degrees of polarization in colliding beams. Presentation will cover similarities and distinctions between linear and re-circulating ERL concepts with focus on their costs, energy efficiency and energy reach. Two examples of HIGS ERL-based factory located in LHC and FCC tunnels will be compared with two concepts of linear ERL colliders. Status of ERLs worldwide will be briefly review and technical challenges facing this promising accelerator technology will be discussed. I will finish talk with discussion of possible technical breakthroughs which can make ERL technology more affordable and more attractive.

We developed a magnetic compression method for relativistic electron beam macro-pulses. Our device, with a significantly larger transfer function R56 compared to the classical chicane structure, enables nanosecond-scale compression of relativistic electron pulses using a compact apparatus measuring just a few meters. This paper introduces the principles of this compression method and presents the results of dynamic simulations.

New technical approaches are under investigation to further push the intensity frontier of the next generation heavy ion synchrotrons. Residual gas dynamics and corresponding charge exchange processes are key issues which need to be overcome by means of advanced UHV system technologies, but also by a focused design of the synchrotron as a whole. Cryogenics and superconductivity enable high field operation but in synergy also enable technologies for stabilizing the dynamic vacuum. Beam loss usually implicated as driver for activation and damages is as well an important initiator for residual gas pressure dynamics. Advanced superconducting cables promise lower energy consumption, fast ramping and higher average beam intensities. The cryo-pumping properties of specially developed cryogenic inserts, can also be used to upgrade existing synchrotrons and enable operation with lower charge states and higher intensities. The advancement of laser technologies may be applied as new devices in heavy ion synchrotrons for advanced manipulations, e.g. non-liouville injection or laser cooling. With FAIR, GSI has expanded its competence for the design of novel high intensity heavy ion synchrotrons.

Winner will talk about his career highlights and the projects he has been involved in.

Nonlinear lattice optimization and correction become increasingly important as storage ring light sources continue to push towards ultra-low emittances. An advanced algorithm based on machine learning technique, called multi-generation Gaussian process optimizer (MG-GPO), was applied to find optimal nonlinear lattice solutions, and was demonstrated to outperform traditional algorithms. It was also implemented in online optimization and resulted in improved machine performance. The need to drive and maintain large beam oscillation amplitude for nonlinear beam dynamics measurement and correction motivated the study of resonant driving with swept frequency. We discovered that there exists a drive amplitude threshold for successful beam excitation. The dependence of the threshold on frequency sweep rate and lattice parameters is theoretically analyzed. The results were verified by both simulations and experimental data.