A5051821990- Particle accelerators and beam dynamics
- Particle Accelerators and Free-Electron Lasers
- Gyrotron and Vacuum Electronics Research
- Nuclear Physics and Applications
- Superconducting Materials and Applications
- Magnetic confinement fusion research
- Advancements in Semiconductor Devices and Circuit Design
- X-ray Spectroscopy and Fluorescence Analysis
- Atomic and Molecular Physics
- Semiconductor materials and devices
- Energy Harvesting in Wireless Networks
- Plasma Diagnostics and Applications
- Antenna Design and Analysis
- Ion-surface interactions and analysis
- Atomic and Subatomic Physics Research
- Electromagnetic Compatibility and Measurements
- Electron and X-Ray Spectroscopy Techniques
- Integrated Circuits and Semiconductor Failure Analysis
- Radiation Effects in Electronics
- Environmental Monitoring and Data Management
- Muon and positron interactions and applications
- Advanced Data Storage Technologies
- Wireless Body Area Networks
- Laser-induced spectroscopy and plasma
- Radiation Therapy and Dosimetry
Los Alamos National Laboratory
2021-2022
Oak Ridge National Laboratory
2015-2020
Argonne National Laboratory
1999-2007
Texas Instruments (United States)
1994-2002
Pacific Northwest National Laboratory
1992-1994
Analyses have been performed on floating-gate avalanche-injection MOS transistor (FAMOS) devices which subjected to write/erase cycling, resulting in hole injection into the tunnel dielectric. Theoretical and experimental analysis of these shown that bits exhibit fast erase due trapped holes are highly modulated by field across Two distinct disturb mechanisms, one is heavily impacted evaluated with regards their temperature dependencies empirical models developed for both mechanisms.< <ETX...
We report the high gradient testing results of two single-cell off-axis coupled standing wave accelerating structures. Two brazed structures with same geometry were tested: one made pure copper (Cu) and a copper–silver (CuAg) alloy silver concentration 0.08%. A peak surface electric field 450 MV/m was achieved in CuAg structure for klystron input power 14.5 MW 1 μs pulse length, which 25% higher than Cu structure. The superb performance because major optimizations cavity's geometry: (1)...
The ITER Ion Cyclotron Heating and Current Drive system (IC H&CD) is designed to deliver 20MW a broad range of plasma scenarios between 40 55MHz, during very long pulses. It consists two broadband equatorial port plug antennas, their pre-matching matching systems, transmission lines, Radio Frequency (RF) Sources High Voltage Power Supplies. overall project schedule has been revised agreed by Council; it re-integrates the second antenna its power supplies in construction baseline sets dates...
Absolute doubly differential cross sections for electron emission are presented 0.5-MeV/u multicharged ion-atom collisions. The collision systems investigated ${\mathrm{B}}^{\mathit{q}+}$, ${\mathrm{C}}^{\mathit{q}+}$ (q=2--5) and ${\mathrm{O}}^{\mathit{q}+}$, ${\mathrm{F}}^{\mathit{q}+}$ (q=3--6) projectiles impacting on helium ions neon argon targets. Laboratory angles between 10\ifmmode^\circ\else\textdegree\fi{} 60\ifmmode^\circ\else\textdegree\fi{} were studied. Under the assumption...
The intense pulsed neutron source (IPNS) rapid cycling synchrotron (RCS) is used to accelerate protons from 50 MeV 450 MeV, at a repetition rate of 30 Hz. original ring design included two identical rf systems, each consisting an accelerating cavity, cavity bias supply, power amplifiers and low-level analog electronics. cavities are located 180 degrees apart in the provide total peak voltage ~21 kV over 2.21-MHz 5.14-MHz revolution frequency sweep. A third system has been constructed...
An unintentional channel hot carrier injection phenomenon is reported for flash memory cells. The occurs near the source metallurgical junction during electrical erase and caused by subthreshold leakage current between floating drains. This mechanism initiated a minority population (electrons) which generated impact ionization around later collected Subsequently, when gate potential approaches threshold voltage, these electrons drift from drain toward source. When they reach depletion...
The Intense Pulsed Neutron Source (IPNS) Rapid Cycling Synchrotron (RCS) delivers 450-MeV protons in 70 ns pulses at 30 Hz to a heavy-metal target producing spallation neutrons for material science research. average current extracted from the RCS is 15 /spl mu/A with peak intensity of 10 amps. large circulating currents generate oscillations bunch which are presently controlled by modulating phase two RF cavities. By adding second harmonic (SH) rf, length can be increased reducing current....
The rapid cycling synchrotron (RCS) of the intense pulsed neutron source (IPNS) at ANL accelerates > 3.0 times 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sup> protons from 50 MeV to 450 with 30-Hz repetition frequency. During acceleration cycle, rf frequency varies 2.21 MHz 5.14 MHz. Presently, beam current is limited by a vertical instability. By analyzing turn-by-turn position monitor (BPM) data, large- amplitude mode 0 and 1...
The IPNS RCS is a rapid cycling synchrotron used to accelerate protons from 50 MeV 450 MeV, 30 times per second. Currently, two single-gap, ferrite-loaded coaxial cavities, located 180/spl deg/ apart, provide total peak accelerating voltage of approximately 21 kV over the 2.2 MHz 5.1 revolution frequency band. An amplifier chain, which includes 2 kW predriver, 20 driver and 100 final, drives each cavity. A third RF system, consisting cavity, cavity bias supply, currently under construction....
In the rapid cycling synchrotron (RCS), a single proton bunch (h=1) is accelerated from 50 MeV to 450 in approximately 14.2 ms. The experiences an instability shortly after injection (<1 ms). During first millisecond, beam bunched but little acceleration takes place; therefore this period similar storage ring mode of operation. Natural vertical oscillations (assumed be tune lines) show rising toward bare value, suggesting neutralization space charge and reduction its detuning effects....
The Rapid Cycling Synchrotron (RCS) of the Intense Pulsed Neutron Source (IPNS) at ANL accelerates > 3.0 times 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">12</sup> protons from 50 MeV to 450 with 30-Hz repetition frequency. During each acceleration cycle, RF varies 2.21 MHz 5.14 MHz. In order improve capture efficiency, we varied injection timing and early voltage profiles. experimental results are compared simulation obtained 1-D...