A5101842987- Particle Accelerators and Free-Electron Lasers
- Advanced X-ray Imaging Techniques
- Gyrotron and Vacuum Electronics Research
- Particle accelerators and beam dynamics
- Laser-Plasma Interactions and Diagnostics
- Gas Dynamics and Kinetic Theory
- Computational Fluid Dynamics and Aerodynamics
- Groundwater flow and contamination studies
- Superconducting Materials and Applications
- Anomaly Detection Techniques and Applications
- Combustion and Detonation Processes
- Particle Detector Development and Performance
- Adsorption, diffusion, and thermodynamic properties of materials
- Human Pose and Action Recognition
- Hydraulic Fracturing and Reservoir Analysis
- Combustion and flame dynamics
- Particle physics theoretical and experimental studies
- X-ray Spectroscopy and Fluorescence Analysis
- Plasma and Flow Control in Aerodynamics
- solar cell performance optimization
Tsinghua University
2021-2023
Chinese Academy of Sciences
2016-2022
Shanghai Advanced Research Institute
2019-2021
China Aerodynamics Research and Development Center
2018-2020
State Key Laboratory of High Temperature Gas Dynamics
2020
Shanghai Institute of Applied Physics
2016-2020
Institute of Mechanics
2019
University of Chinese Academy of Sciences
2018
A hard X-ray Split-and-Delay Line (SDL) under construction for the Materials Imaging and Dynamics station at European X-Ray Free-Electron Laser (XFEL) is presented. This device aims providing pairs of pulses with a variable time delay ranging from −10 ps to 800 in photon energy range 5 10 keV correlation pump-probe experiments. custom designed mechanical motion system including active feedback control ensures that high demands stability accuracy can be met design goals achieved. Using...
The echo-enabled harmonic generation (EEHG) scheme holds promising prospects for efficiently generating intense coherent radiation at very high harmonics of a conventional ultraviolet seed laser. We report the lasing EEHG free-electron laser (FEL) an extreme (EUV) wavelength with seeded FEL facility, Shanghai soft x-ray FEL. For first time, we have benchmarked basic theory by measuring bunching factor distributions over one octave down to EUV region. Our results demonstrated key advantages...
The spectroscopic techniques for time-resolved fine analysis of matter require coherent X-ray radiation with femtosecond duration and high average brightness. Seeded free-electron lasers (FELs), which use the frequency up-conversion an external seed laser to improve temporal coherence, are ideal providing fully soft pulses. However, it is difficult operate seeded FELs at a repetition rate due limitations present state-of-the-art systems. Here, we report novel self-modulation method enhancing...
Traffic accidents present complex challenges for autonomous driving, often featuring unpredictable scenarios that hinder accurate system interpretation and responses.Nonetheless, prevailing methodologies fall short in elucidating the causes of proposing preventive measures due to paucity training data specific accident scenarios.In this work, we introduce AVD2 (Accident Video Diffusion Accident Description), a novel framework enhances scene understanding by generating videos aligned with...
It is a long-standing challenge for laser technologies to generate intense fully coherent pulses in the x-ray regime. Here, we demonstrate an external seeding mechanism, termed echo-enabled harmonic cascade (EEHC) generating and ultrashort soft pulses. The mechanism uses generation as first stage, producing extreme ultraviolet that seed second stage free-electron (FEL) with high-gain setup. Benefiting from low sensitivity electron-beam imperfections of EEHC, generated high-power nearly...
Low longitudinal emittance means small energy spread and short bunch length, which makes high-power short-wavelength coherent radiation possible. In a storage ring, due to quantum excitation, the equilibrium is mainly overall contribution of all bend-related elements, such as bends, undulators laser modulators. By introducing Twiss function analyzing 6D one-turn map in 3D form, these elements theoretically studied this paper, general method for minimizing ring proposed. An integrated...
We propose a new scheme to generate high-brightness and temporal coherent soft x-ray radiation in seeded free-electron laser. The proposed is based on the harmonic generation (CHG) superradiant principles. A CHG first used signal at ultrahigh harmonics of seed. This then amplified by series chicane-undulator modules via fresh bunch processes following radiator. Using representative realistic set parameters, three-dimensional simulations have been carried out results demonstrated that 10...
Nomenclature L = distance between hinge point of double-wedge model and shock-shock interaction point, mm R nose radius the test model, T translational-rotational temperature, K v vibrational Δ shock standoff distance, θ polar angle measured from stagnation line, deg φ symmetric axis
We propose a new scheme to generate high-brightness and temporal coherent soft x-ray radiation in seeded free-electron laser. The proposed is based the harmonic generation (CHG) superradiant principles. A CHG first used signal at ultra-high harmonics of seed. This then amplified by series chicane-undulator modules via fresh bunch processes following radiator. Using representative realistic set parameters, three-dimensional simulations have been carried out results demonstrated that 10...
In this Letter, we report on the concept and analysis of a low-emittance electron storage ring, in which beams undergo an early-stage self-amplified spontaneous emission lasing process turn-by-turn basis. The for each pass through long undulator ring is terminated when radiated power still negligible compared to total synchrotron loss circulation, can be maintained equilibrium state that supports sustainable lasing. A self-consistent model derived evaluation properties beams, design with...
In this Letter, we report on the concept and analysis of a low-emittance electron storage ring, in which beams undergo an early-stage self-amplified spontaneous emission lasing process turn-by-turn basis. The for each pass through long undulator ring is terminated when radiated power still negligible compared to total synchrotron loss circulation, can be maintained equilibrium state that supports sustainable lasing. A self-consistent model derived evaluation properties beams, design with...