A5019097532- Particle Accelerators and Free-Electron Lasers
- Particle accelerators and beam dynamics
- Superconducting Materials and Applications
- Magnetic confinement fusion research
- Gyrotron and Vacuum Electronics Research
- Remote Sensing and Land Use
- Laser Design and Applications
- Laser-Plasma Interactions and Diagnostics
- Photocathodes and Microchannel Plates
- Dust and Plasma Wave Phenomena
- Plasma Diagnostics and Applications
- Ionosphere and magnetosphere dynamics
- Atomic and Molecular Physics
- Advanced X-ray Imaging Techniques
- Particle physics theoretical and experimental studies
- Remote Sensing in Agriculture
- Gas Dynamics and Kinetic Theory
- GaN-based semiconductor devices and materials
- Particle Detector Development and Performance
- Nuclear Physics and Applications
- Optical Wireless Communication Technologies
- Physics of Superconductivity and Magnetism
- Autonomous Vehicle Technology and Safety
- Orbital Angular Momentum in Optics
- Nanopore and Nanochannel Transport Studies
Brookhaven National Laboratory
2019-2024
Stony Brook University
2018-2023
University of Science and Technology of China
1997-2022
Sichuan Agricultural University
2022
Wuhan University
2022
Rice Research Institute
2022
Kyungsung University
2013
Northwest University
2013
Institute of Physics
2012
Japan Atomic Energy Agency
2008
Continuous-wave photoinjectors operating at high accelerating gradients promise to revolutionize many areas of science and applications. They can establish the basis for a new generation monochromatic x-ray free electron lasers, high-brightness hadron beams, or microchip production. In this Letter we report on record-performing superconducting rf gun with ${\mathrm{CsK}}_{2}\mathrm{Sb}$ photocathode. The is generating charge bunches (up $10\text{ }\text{ }\mathrm{nC}/\text{bunch}$) low...
Abstract High brightness, high charge electron beams are critical for a number of advanced accelerator applications. The initial emittance the beam, which is determined by mean transverse energy (MTE) and laser spot size, one most important parameters determining beam quality. bialkali photocathodes illuminated visible have advantages quantum efficiency (QE) low MTE. Furthermore, Superconducting Radio Frequency (SRF) guns can operate in continuous wave (CW) mode at accelerating gradients,...
Estimating the aboveground biomass (AGB) of rice using remotely sensed data is critical for reflecting growth status, predicting grain yield, and indicating carbon stocks in agroecosystems. A combination multisource has great potential providing complementary datasets, improving estimation accuracy, strengthening precision agricultural insights. Here, we explored to estimate AGB by a spectral vegetation indices wavelet features (spectral parameters) derived from canopy reflectance texture...
Cooling of beams gold ions using electron bunches accelerated with radio-frequency systems was recently experimentally demonstrated in the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. Such an approach is new and opens possibility this technique higher energies than possible electrostatic acceleration beams. The challenges include generation suitable for cooling, delivery required quality to cooling sections without degradation beam angular divergence energy spread,...
2021年12月26日,5米光学02星在太原卫星发射中心成功发射,星上装载的主要载荷之一—热红外相机采用8192元长线阵长波红外探测器推扫成像,可以获取星下点地面像元分辨率优于16m、噪声等效温差小于0.1K@300K、幅宽大于115km的7.7μm~10.5μm谱段热红外影像。相比国内外在轨热红外遥感相机,该相机同时实现高分辨率、高灵敏度和大幅宽观测,能够实现空间和温度的高效率精细化探测,具有明显优势。文章介绍了该相机的组成、工作原理、相机关键技术及实现情况,给出地面测试与试验结果,并简要介绍在轨测试和应用情况。相机目前在轨稳定运行,性能优异,已获取大量高分辨率热红外影像,可为后续同类载荷研制提供参考。
A high-current high-brightness electron accelerator for low-energy RHIC cooling (LEReC) was successfully commissioned at Brookhaven National Laboratory. The LEReC includes a dc photoemission gun, laser system, photocathode delivery magnets, beam diagnostics, superconducting rf booster cavity, and set of normal conducting cavities to provide enough flexibility tune the in longitudinal phase space. Cooling with nonmagnetized accelerated beams requires corrections obtain small momentum spread...
Interaction of hadrons with electron beam in a modulator is an important part coherent cooling (CeC), novel method for hadron beams. Being untested technique, the CeC undergoing proof-of-principle test at Brookhaven National Laboratory (BNL). Simulation this process realistic propagating through quadrupole beamline constitutes very challenging problem. We successfully used code space these simulations and obtained accurate dependences modulation on position velocity ions. good numerical...
Microwave heating is an important method that widely used in industries. Developing a uniform electromagnetic field inside the cavities might be crucial challenge to avoid localized overheating. The uniformity of governed by configurations waveguides. To better understand design cavities, simulations are carried out. This paper discussed comparison result between two waveguides and introduced use objective function order evaluate temperature uniformity. As conclusion, it was found out using...
We report a new monolithic structure of GaN-based light-emitting diode (LED) which can be operated under high voltage or alternative current. Differing from the conventional single LED chip, (MLED) array contains microchips are interconnected in series parallel. The key chip fabrication processing methods include deep dry etching, sidewall insulated protection, and electrode interconnection. A 12 V blue light emitting was designed fabricated our experiment. forward current—voltage...
In this paper we describe an instability, which called a Plasma-Cascade Amplifier, occurring in electron beams propagating along straight trajectory.
The SPACE code is a parallel, relativistic, three-dimensional, electromagnetic, particle-in-cell developed for the simulations of beam dynamics and interactions. can perform with various distributions, different types boundary conditions, flexible line, as well provide sufficient processing routines data analyses visualization. Self-consistent, highly resolved realistic were performed using to study coherent electron cooling (CeC) experiment two amplifiers, free laser (FEL) plasma-cascade...
The recent achievements in the performance of superconducting RF (SRF) photoinjectors have opened a new era development reliable high-brightness CW electron sources. While SRF guns become one most promising technologies, compatibility environment with complex photocathodes remains on forefront modern accelerator science. cavities operate at cryogenic temperatures providing ultra-high vacuum (UHV) highly beneficial for photocathode performance. However, necessity to keep room temperature...
There are numerous instabilities present in charged particle beams that undergo exponential growth and reach saturation. In various applications, such as free-electron lasers or micro-bunching light sources, achieving saturation is desirable. Conversely, there applications where these utilized linear broad-band amplifiers for signals embedded the beam. latter scenario, of an instability induces non-linear distortions imprinted signal, thereby limiting useful range amplifiers. Accurate...
Solenoids are frequently used for focusing low-energy beams. In this paper, we show how they can serve as multipurpose diagnostics tools to measure various beam parameters, including energy, emittance, the second moments of transverse distribution, and position angle with respect solenoid’s axis. The energy measurement is based on rotation plane motion, opposed generating dispersion a dipole. Measurement trajectory solenoid axis done by analyzing orbit downstream while varying its current....
Microscopic, or short-wavelength, instabilities are known for a drastic reduction of the beam quality and strong amplification noise in beam. Space charge coherent synchrotron radiation to be leading causes such instabilities. In this paper, we present rigorous 3D theory driven by space-charge forces. We define condition when our is applicable an arbitrary accelerator system with coupling. Finally, derive linear integral equation describing instability identify conditions it can reduced...
In this paper we describe a new microbunching instability occurring in charged particle beams propagating along straight trajectory. The nature of these exponentially growing plasma oscillations gave the reason for its name: plasma-cascade instability. Such can strongly amplify longitudinal originating from beam's shot noise, even to point saturation. Resulting random density and energy microstructures drastically reduce beam quality. Conversely, such drive novel high-power sources broadband...
As a mature product with high commercialization, the fiber optic gyroscope is susceptible to influence of environmental factors in actual use, which affects measurement accuracy. In order improve temperature adaptability and efficiency compensation engineering process gyroscope, modeling method based on multilayer perceptron proposed. First, working principle mechanism that causes error analyzed. Then, neural network model perceptron, structure design carried out, existing data used train...
The morphology of nanospheres is crucial for designing the nanofabrication in nanosphere lithography. Here, by plasma etching, controllable tailoring realized and its dependence on initial shape, microscopic roughness, etching conditions investigated quantitatively. results show that shape evolution strongly depends gas, power, process duration. Particularly, aspect ratio (diameter/height) significantly increases with violent turning spherical into tiny ellipsoidal nanoparticles. findings...