A5013987617- Particle accelerators and beam dynamics
- Particle Accelerators and Free-Electron Lasers
- Nuclear Physics and Applications
- Superconducting Materials and Applications
- Magnetic confinement fusion research
- Particle Detector Development and Performance
- Gyrotron and Vacuum Electronics Research
- Atomic and Subatomic Physics Research
- Information and Cyber Security
- Atomic and Molecular Physics
- Muon and positron interactions and applications
- Space Science and Extraterrestrial Life
- Canadian Identity and History
- Quantum Chromodynamics and Particle Interactions
- Laser Design and Applications
- Laser-Matter Interactions and Applications
- High-Energy Particle Collisions Research
- Nuclear reactor physics and engineering
- Quantum optics and atomic interactions
- Dark Matter and Cosmic Phenomena
- Fusion materials and technologies
- Spectroscopy and Quantum Chemical Studies
- International Science and Diplomacy
- Astro and Planetary Science
- Cold Atom Physics and Bose-Einstein Condensates
West Yorkshire Police
2022
University of Kent
2022
Argonne National Laboratory
2015
Oak Ridge National Laboratory
1987-2014
Fermi National Accelerator Laboratory
2012-2014
Spallation Neutron Source
2006
Cornell University
1997
Henderson Community College
1996
Yale University
1992-1993
City College of New York
1992
A simple prescription for scaling diatomic potentials so that they have a common dissociation limit and fixed curvature near the minimum is used to examine 35 which are known over relatively large fractions of their well depths. These global comparisons reveal greater similarity, particularly among chemically related molecules, than might be predicted from spectroscopic properties based on derivatives potential its minimum.
Through multiphoton ionization measurements, we have observed the interference of five-photon and internally generated fifth-harmonic excitation processes in \ensuremath{\Delta}J=1 even-odd parity resonant transitions Xe Ar. In agreement with theory, these resonances are not observable single-pass laser beams, but convincingly counterpropagating beams. negatively dispersive regions 5d${[3/2]}^{0}$J=1 level Xe, tunable light is by phase matching various buffer-gas mixtures. The profiles good...
We have extended observations of total cancellation three-photon atomic excitation by internally generated fields due to four-wave mixing. The process was found occur as predicted in an mode involving two photons frequency ${\ensuremath{\omega}}_{1}$ and one ${\ensuremath{\omega}}_{2}$, plus the four-wave-mixing field at 2${\ensuremath{\omega}}_{1}$+${\ensuremath{\omega}}_{2}$. Experiments were conducted on 6s state Xe.
Summary Ecological farming, such as organic and low‐input is gaining popularity in the public discourse. One question how this type of farming may impact farm labour from a socio‐economic point view. The article first discusses practices (i.e. with lower reliance on inputs derived fossil fuels) affect economic returns to labour, measured farm’s revenue per hour input, data Farm Accountancy Data Network (FADN) 2004‐‐2015 for four European countries. Returns appear be highest at two extremes –...
This paper presents a scheme for three-step laser-based stripping of an ${\mathrm{H}}^{\ensuremath{-}}$ beam charge exchange injection into high-intensity proton ring. First, atoms are converted to ${\mathrm{H}}^{0}$ by Lorentz in strong magnetic field, then neutral hydrogen excited from the ground state upper levels laser, and remaining electron, now more weakly bound, is stripped field. The energy spread particles gives rise Doppler broadened absorption linewidth, which makes inefficient...
The search for s-channel production of light neutral particles coupled to ${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$ has been extended by more than 3 orders magnitude in lifetime beyond the region which is accessible elastic scattering. whole mass range 1500\ensuremath{\lesssim}${\mathit{M}}_{\mathit{X}}^{0}$\ensuremath{\lesssim}1860 keV/${\mathit{c}}^{2}$ suggested observation anomalous pairs heavy-ion collisions investigated. These measurements find no evidence states...
The Spallation Neutron Source (SNS) radio-frequency quadrupole (RFQ) had resonance control instabilities at duty factors higher than approximately 4%. Systematic investigations have been carried out to understand the cause of instability and ensure operational stability RFQ. most critical source is revealed be an interaction between hydrogen released by beam bombardments RFQ rf field resulting in a discharge, which consumes additional power could operate unstable region. This paper reports...
We report results of an experiment to search for a resonance enhancement the ${\mathit{e}}^{+}$${\mathit{e}}^{\mathrm{\ensuremath{-}}}$ scattering cross section in metallic Li target utilizing energy-tunable monoenergetic positron beam. Within statistical uncertainties (0.27%) no evidence has been observed deviations from Bhabha over entire invariant-mass region 1560 keV/${\mathit{c}}^{2}$${\mathit{M}}_{\mathit{X}}^{0}$1860 keV/${\mathit{c}}^{2}$ that can be associated with sum-peak energies...
The Superconducting Linac at SNS has been operating with beam for almost two years. As the first operational pulsed superconducting linac, many of aspects its performance were unknown and unpredictable. A lot experience gathered during commissioning components, turn on operation increasingly higher power. Some cryomodules have cold well over years extensively tested. consistently conducted 4.4 K 10 15 pulses per second, some tested 30 60 Hz tests performed 2 K. Careful balance between safe...
The Spallation Neutron Source accelerator systems will deliver a 1.0 GeV, 1.4 MW proton beam to liquid mercury target for neutron scattering research. complex consists of an H-injector, capable producing one-ms-long pulses at 60 Hz repetition rate with 38 mA peak current, 1 GeV linear accelerator, accumulator ring and associated transport lines. 2.5 MeV from the Front End is accelerated 86 in Drift Tube Linac, then 185 Coupled-Cavity Linac finally Superconducting Linac. With completion...
Linac utilizes several accelerating structures operating at two frequencies. CCL and SCL operate 805 MHz while 402.5 is used for RFQ DTL. Beam transfer from the previous part of accelerator to subsequent one requires careful longitudinal matching improve beam transmission minimize losses. Longitudinal parameters have been investigated with help three Bunch Shape Monitors installed in inter-segments first Module. The results bunch shape observations different settings are presented. emittance...
Abstract: Toronto's Rochdale College (1968–1975) represented something much more than simply a new venue for countercultural experimentation and identity in the centre of English Canada's biggest city. It served as bridge between hip emphasis on public performativity that characterized Yorkville scene mid-1960s private separatism early 1970s. The symbolic association impenetrability was central to both Rochdalians' self-identification its perception by outsiders; there also were connections...
In the SNS accumulator ring, ceramic vacuum chambers are used for 8 injection kickers to avoid shielding of a fast-changing kicker field and minimize eddy current heating. The inner surface was coated with Cu reduce beam coupling impedance provide passage image current, TiN over layer secondary electron yield. ferrite surfaces 14 extraction modules were also TiN. Customized masks produce longitudinal coating strips 1 cm x 5 ∼ mm separation among strips. methods, physical electromagnetic...
We describe the techniques which will be employed for establishing RF setpoints in SNS Superconducting linac. The longitudinal tuneup accomplished using phase-scan methods, as well a technique that makes use of beam induced field unpowered cavity [1].