22 papers
This paper proposes and analyzes a novel "synchrotron radiation power leveling" strategy for the Future Circular Collider (FCC-hh), where beam energy is dynamically adjusted during a physics store to manage heat loads from synchrotron radiation, thereby increasing both peak and integrated luminosity and significantly boosting the production rates of key physics processes like di-Higgs events.
This paper proposes a conceptual design for a compact, multi-turn recirculating linear accelerator-based free electron laser that delivers high-brightness, MHz-repetition-rate EUV to soft X-ray pulses within a footprint of less than 100 meters, significantly reducing costs and expanding accessibility for university-scale research while demonstrating that synchrotron radiation effects do not limit beam quality.
This paper presents simulation results demonstrating that an unseeded optical klystron free-electron laser, enhanced by a novel chicane-embedded optical delay scheme to mitigate slippage, can generate compact, sub-picosecond, multi-hundred-megawatt terahertz pulses at resonant wavelengths of 10, 30, and 100 μm.
This paper presents an unsupervised deep-learning framework based on a U-Net architecture that significantly enhances beam emittance evaluation by denoising low-signal images to reconstruct transverse phase-space distributions and detect beam halos with unprecedented resolution, even under challenging non-Gaussian and noisy operating conditions.
This paper introduces and compares a new full arc bunch compression scheme against standard four-dipole and five-dipole chicanes, demonstrating that while both the arc and five-dipole methods significantly outperform the standard chicane in reducing emittance dilution and microbunching for hard and soft X-ray FELs, optimal facility design (such as for UK-XFEL) requires the ability to switch between these advanced schemes on a bunch-by-bunch basis.
This paper presents a conceptual design study for a Transverse Deflecting Structure (TDS) at the DALI accelerator facility, detailing its physical principles, engineering considerations, and role in enabling direct longitudinal bunch profile measurements and phase space reconstruction.
This study demonstrates that delivering low-energy (2.5 MV) photon beams at an extended source-to-patient distance (4 m) in an upright configuration achieves significantly sharper penumbra, lower surface dose, and higher peak-to-valley ratios in spatially fractionated plans compared to standard 6 MV coplanar radiotherapy, offering a viable alternative to FLASH for high-flux sources.
This paper analyzes how collective effects like longitudinal space-charge and coherent synchrotron radiation induce stochastic phase distortions and spectral broadening in low-energy terahertz optical klystrons, establishing fundamental constraints on their spectral purity and harmonic bunching for future facility design.
This paper establishes a kinetic field theory for beam-plasma collective oscillations in intermediate-energy charged-particle beams, deriving dispersion relations and critical density thresholds that are validated by a Prometheus beta-VAE analyzing particle-in-cell simulation data to confirm predicted signatures like density-tunable resonances and Friedel oscillations.
This study utilizes FIB tomography to reveal that while tin-deficient regions are more prevalent in Nb3Sn thin films than previously thought, their location beneath the surface suggests they are unlikely to be the primary cause of the limited accelerating gradient in superconducting radiofrequency cavities.
This paper experimentally demonstrates that passive plasma lenses can preserve free-electron-laser-quality slice emittance while focusing beams two orders of magnitude more strongly than quadrupole magnets, with controllable focal parameters.
This paper proposes a multiple-echo-enabled harmonic generation (multi-EEHG) scheme that applies successive excitation-echo cycles to a single stored bunch within one revolution, enabling the generation of high-brightness, few-meV coherent X-ray pulses at multiple wavelengths for simultaneous multi-beamline operation in next-generation storage-ring light sources.
This paper analyzes the discrete nature of electron emission at the mesoscale by examining individual point charge spacing under space-charge limited conditions, deriving scaling laws through simplified models, and validating them against computer simulations.
This lecture provides an overview of the fundamental principles, design challenges, and operational strategies of beam collimation systems in high-intensity hadron accelerators, using the Large Hadron Collider as the primary reference for state-of-the-art technologies.
This paper presents a unified framework for coupled beam optics in accelerators that resolves the non-uniqueness of existing parametrizations by identifying a common gauge freedom, thereby introducing bounded, gauge-invariant coupling descriptors and a practical continuity method to ensure consistent mode labeling across different theoretical approaches.
This study presents the first experimental characterization of plasma parameters and carbon decontamination rates in microwave resonators used for particle accelerators, utilizing Langmuir probes and quartz crystal microbalances to optimize the in-situ plasma cleaning of superconducting radio frequency cavities.
This paper proposes a novel, decentralized approach to securing the domestic supply of the medical isotope Mo by adapting high-current deuterium cyclotrons, originally designed for neutrino research, to generate sufficient neutrons for isotope production without relying on nuclear reactors or highly enriched uranium.
This study demonstrates that applying automatic differentiation to a 21-equation model enables the efficient analysis of fully coupled 3D envelope instability in particle accelerators, revealing a previously unreported instability stopband caused by space-charge coupling that would otherwise require computationally intractable 441 equations to solve.
This paper proposes a computationally efficient chaos indicator based on the norm of the tangent map derived via automatic differentiation to accelerate dynamic aperture optimization, as demonstrated in the ALS-U lattice design.
This paper presents ion-motion simulations of beam-driven plasma wakefields at the FLASHForward facility, demonstrating that the motion of ions, often assumed to be stationary, significantly impacts beam dynamics by causing longitudinally dependent emittance growth.