A5084926632- X-ray Spectroscopy and Fluorescence Analysis
- Atomic and Molecular Physics
- Scientific Measurement and Uncertainty Evaluation
- Nuclear Physics and Applications
- Remote-Sensing Image Classification
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Mechanics and Applications
- Advanced Chemical Physics Studies
- Integrated Circuits and Semiconductor Failure Analysis
- Remote Sensing in Agriculture
- Climate variability and models
- Climate change impacts on agriculture
- Quantum optics and atomic interactions
- Plasma Applications and Diagnostics
- Calibration and Measurement Techniques
- Electrohydrodynamics and Fluid Dynamics
- Advanced Electrical Measurement Techniques
- Nuclear physics research studies
- Advanced X-ray and CT Imaging
- Land Use and Ecosystem Services
- Space Exploration and Technology
- Electron and X-Ray Spectroscopy Techniques
- Quantum Information and Cryptography
- Laser-induced spectroscopy and plasma
- Plasma Diagnostics and Applications
Ulsan National Institute of Science and Technology
2016-2024
Pusan National University
2012
For more than 40 years, most astrophysical observations and laboratory studies of two key soft x-ray diagnostic 2p-3d transitions, 3C 3D, in Fe XVII ions found oscillator strength ratios f(3C)/f(3D) disagreeing with theory, but uncertainties had precluded definitive statements on this much studied conundrum. Here, we resonantly excite these lines using synchrotron radiation at PETRA III, reach, a millionfold lower photon intensities, 10 times higher spectral resolution, 3 smaller uncertainty...
We demonstrate a widely applicable technique to absolutely calibrate the energy scale of x-ray spectra with experimentally well-known and accurately calculable transitions highly charged ions, allowing us measure K-shell Rydberg spectrum molecular O$_2$ 8 meV uncertainty. reveal systematic $\sim$450 shift from previous literature values, settle an extraordinary discrepancy between astrophysical laboratory measurements neutral atomic oxygen, latter being calibrated against aforementioned...
We resonantly excite the $K$ series of ${\mathrm{O}}^{5+}$ and ${\mathrm{O}}^{6+}$ up to principal quantum number $n=11$ with monochromatic x rays, producing $K$-shell holes, observe their relaxation by soft-x-ray emission. Some photoabsorption resonances reveal strong two-electron--one-photon (TEOP) transitions. find that for ${[{(1s2s)}_{1}5{p}_{3/2}]}_{3/2;1/2}$ states, TEOP is far stronger than radiative decay competes usually much faster Auger path. This enhanced arises from a...
Abstract. Many satellite sensors including Landsat series have been extensively used for land cover classification. Studies conducted to mitigate classification problems associated with the use of single data (e.g., such as cloud contamination) through multi-sensor fusion and time data. This study investigated two areas different environment climate conditions: one in South Korea other US. Cropland was by using multi-temporal 5, Radarsat-1 digital elevation models (DEM) based on machine...
Abstract. The reduction of drought impacts may be achieved through sustainable management and proactive measures against disaster. Accurate timely provision information is essential. In this study, forecasting models to provide high-resolution based on indicators for ungauged areas were developed. developed predict indices the 6-month Standardized Precipitation Index (SPI6) Evapotranspiration (SPEI6). An interpolation method multiquadric spline as well three machine learning tested. Three...
Summary form only given. Microplasmas generated within cavities having the of a truncated paraboloid, introduced by Kim et al. [Appl. Phys. Lett. 94, 011503 (2009)], have been simulated numerically with two-dimensional, fluid computational model. Microcavities parabolic sidewalls, fabricated in nanoporous alumina (Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) and upper (primary...
A key requirement for the correct interpretation of high-resolution X-ray spectra is that transition energies are known with high accuracy and precision.We investigate K-shell features Ne, CO 2 , SF 6 gases, by measuring their photo ion-yield at BESSY II synchrotron facility simultaneously 1s-np fluorescence emission He-like ions produced in Polar-X EBIT.Accurate ab initio calculations transitions these provide basis calibration.While result agrees well previous measurements, spectrum...