A5026617181- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Electron and X-Ray Spectroscopy Techniques
- Advanced X-ray Imaging Techniques
- Advanced Electron Microscopy Techniques and Applications
- Gyrotron and Vacuum Electronics Research
- Superconducting Materials and Applications
- Advancements in Photolithography Techniques
- Photocathodes and Microchannel Plates
- Laser-Plasma Interactions and Diagnostics
- X-ray Spectroscopy and Fluorescence Analysis
- Radiation Therapy and Dosimetry
- Crystallography and Radiation Phenomena
- Nuclear Physics and Applications
- Particle Detector Development and Performance
- Photonic and Optical Devices
- Advanced optical system design
- Surface and Thin Film Phenomena
- Optical Coatings and Gratings
- Magnetic confinement fusion research
- Particle physics theoretical and experimental studies
- Nuclear reactor physics and engineering
- Nuclear Materials and Properties
- Laser Design and Applications
- Distributed and Parallel Computing Systems
ShanghaiTech University
2018-2024
Shanghai Institute of Applied Physics
2023
Chinese Academy of Sciences
2023
Brookhaven National Laboratory
2018-2022
Lawrence Berkeley National Laboratory
2011-2021
Technical University of Denmark
2020
Shanghai Jiao Tong University
2018
Southern University of Science and Technology
2018
Stony Brook University
2018
Peking University
2018
The status of the research on muon colliders is discussed and plans are outlined for future theoretical experimental studies. Besides continued work parameters a 3-4 0.5 TeV center-of-mass (CoM) energy collider, many studies now concentrating machine near 0.1 that could be factory s-channel production Higgs particles. We discuss various components in such colliders, starting from proton accelerator needed to generate pions heavy-Z target proceeding through phase rotation decay ($\pi \to \mu...
We experimentally investigate surface-plasmon assisted photoemission to enhance the efficiency of metallic photocathodes for high-brightness electron sources. A nanohole array-based copper surface was designed exhibit a plasmonic response at 800 nm, fabricated using focused ion beam milling technique, optically characterized and tested as photocathode in high power radio frequency photoinjector. Because larger absorption localization optical field intensity, charge yield observed under...
We propose and demonstrate a novel scheme to produce ultrashort ultrastable MeV electron beam. In this scheme, the beam produced in photocathode radio frequency (rf) gun first expands under its own Coulomb force with which positive energy chirp is imprinted longitudinal phase space. The then sent through double bend achromat dispersion where electrons at bunch tail lower energies follow shorter paths thus catch up head, leading compression. show that optimized parameter sets, whole path from...
We describe a spin-resolved electron spectrometer capable of uniquely efficient and high energy resolution measurements. Spin analysis is obtained through polarimetry based on low-energy exchange scattering from ferromagnetic thin-film target. This approach can achieve similar analyzing power (Sherman function) as state-of-the-art Mott polarimeters, but with much 100 times improved efficiency due to increased reflectivity. Performance further enhanced by integrating the polarimeter into...
We present a design of superconducting magnets, optimized for application in gantry proton therapy. have introduced new magnet concept, called an alternating-gradient canted cosine theta (AG-CCT) which is compatible with achromatic layout. This layout allows large momentum acceptance. The 15 cm radius the bore aperture enables pencil beam scanning front SC-magnet. optical and dynamic performance based on these magnets has been analyzed using fields derived (via Biot-Savart law) from actual...
Exceptional points (EPs) could potentially enhance the sensitivity of an optical sensing system by orders magnitude. Higher-order EP systems, having more complex physics, can further boost this parameter. In paper, we investigate response order high-order non-Hermitian systems and provide a guideline for designing sensor with high order. Based on design rule, propose demonstrate fourth-order response, analyze its associated properties. The four resonant wavelengths our simultaneously...
Driven by life-science applications, a mega-electron-volt Scanning Transmission Electron Microscope (MeV-STEM) has been proposed here to image thick frozen biological samples as conventional (TEM) may not be suitable thicker than 300–500 nm and various volume electron microscopy (EM) techniques either suffering from low resolution, or speed. The high penetration of inelastic scattering signals MeV electrons could make the MeV-STEM an appropriate microscope for 10 μm more with nanoscale...
Free-electron lasers and energy recovery linacs represent a new generation of ultra-high brightness electron accelerator based x-ray sources. Photocathodes are critical performance-limiting component these systems. Here, we describe the development photocathodes on potassium-cesium-antimonide that satisfy many key requirements future light sources, such as robustness, high quantum efficiency when excited with visible light, low transverse emittance.
Measurements of the intrinsic emittance and transverse momentum distributions obtained from a metal (antimony thin film) photocathode near below photoemission threshold are presented. show that is limited by lattice temperature cathode as incident photon energy approaches threshold. A theoretical model to calculate this An excellent match between experimental measurements calculations demonstrated. These relevant low electron sources for Free Electron Lasers Ultrafast Diffraction experiments.
An x-ray streak camera with high resolution in both temporal and spatial dimensions has been developed. It is achieved by using extraction-mesh acceleration a large opening aperture magnetic solenoid lens design. High resolutions the can be retained wide 53ps time window. A of 233fs 10μm have demonstrated Au photocathode.
Recent studies have shown that strong, alternating focusing magnets can be used to greatly increase the momentum acceptance of hadron therapy gantries. With high gradients achievable with superconducting a level reached which may significant implications medical gantries and introduction technology in this area. The design such magnet system for proton gantry will presented. Canted-Cosine-Theta concept is extended curved generating desired bending fields achromatic optics. Magnetic,...
Electron spin plays important roles in determining the physical and chemical properties of matter. However, measurements electron are poor quality, impeding development material sciences, because polarimeter has a low efficiency. Here, we show an imaging-type exchange-scattering with 6786 channels $8.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ single channel As demonstration, fine structure electronic states bismuth (111) is investigated, for which strong Rashba-type splitting...
The Advanced Light Source (ALS) is a third-generation light source in operation since 1993. This providing state-of-the-art performance to more than 40 beamlines and their users, due the upgrades that have been completed over last few years. storage ring upgrade project developed here will allow ALS provide beamline users with higher photon beam brightness (factor of 2 or 3) by having its lattice modified. Forty-eight harmonic sextupole magnets integrated dipole correctors skew quadrupole...
We determine the limit of lowest achievable photoemitted electron temperature, and therefore maximum brightness, from unstructured photoemitting materials producing dense relativistic or nonrelativistic photoelectron beams. The is given by heating that occurs just after emission into vacuum, due to poorly screened Coulomb interactions equivalent disorder induced seen in ultracold neutral plasmas. first show traditional analytic methods collisions fail for calculation this strongly coupled...