A5005225322- Particle accelerators and beam dynamics
- Particle Accelerators and Free-Electron Lasers
- Nuclear Physics and Applications
- Magnetic confinement fusion research
- Superconducting Materials and Applications
- Nuclear reactor physics and engineering
- Particle Detector Development and Performance
- Laser-Plasma Interactions and Diagnostics
- Plasma Diagnostics and Applications
- Gyrotron and Vacuum Electronics Research
- Atomic and Subatomic Physics Research
- Atomic and Molecular Physics
- Distributed and Parallel Computing Systems
- Laser Design and Applications
- Non-Destructive Testing Techniques
- Laser-Matter Interactions and Applications
- Particle physics theoretical and experimental studies
- Anomaly Detection Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- Scientific Computing and Data Management
- Machine Fault Diagnosis Techniques
- Fault Detection and Control Systems
- Radiation Detection and Scintillator Technologies
- Oil and Gas Production Techniques
- Optical Systems and Laser Technology
Oak Ridge National Laboratory
2015-2024
Oak Ridge Associated Universities
2024
Government of the United States of America
2022-2023
University of Tennessee at Knoxville
2017-2019
United States Department of Energy
2006
Spallation Neutron Source
2006
Brookhaven National Laboratory
2002-2003
Indiana University Bloomington
1999-2003
Indiana University
2002
European Organization for Nuclear Research
2002
Abstract Colliders are essential research tools for particle physics. Numerous future collider proposal were discussed in the course of US high energy physics community strategic planning exercise Snowmass'21 . The Implementation Task Force (ITF) has been established to evaluate proposed accelerator projects performance, technology readiness, schedule, cost, and environmental impact. Corresponding metrics developed uniform comparison proposals ranging from Higgs/EW factories multi-TeV...
The particle accelerator simulation code PyORBIT is presented. structure, implementation, history, parallel and capabilities, future development of the are discussed. a new implementation extension algorithms original ORBIT that was developed for Spallation Neutron Source at Oak Ridge National Laboratory. has two level structure. upper uses Python programming language to control flow intensive calculations performed by lower implemented in C + language. capabilities based on MPI...
The method of H- photoionization is interesting for laser assisted charge exchange injection. In this paper, the model and computation negative hydrogen ion by using strong lasers considered. development work motivated pure photodetachment electron from when it not convenient or possible to use stripping magnet. Herein we develop a calculation high efficiency time dependent wave equation with application powerful lasers. We compare precise simplified through linear cross section interaction....
This article describes real time series datasets collected from the high voltage converter modulators (HVCM) of Spallation Neutron Source facility. HVCMs are used to power linear accelerator klystrons, which in turn produce high-power radio frequency accelerate negative hydrogen ions (H-). Waveform signals have been operation more than 15 HVCM systems categorized into four major subsystems during years 2020-2022. The data collection process occurred facility Oak Ridge, Tennessee United...
This Letter presents the first complete six dimensional phase space measurement of a beam in an accelerator. The was made on Spallation Neutron Source Beam Test Facility. data reveal previously unknown correlations distribution that are not visible lower dimensionality measurements. shown to be intensity dependent.
This Letter reports on the first demonstration of laser-assisted ${\mathrm{H}}^{\ensuremath{-}}$ charge exchange for microsecond duration beam pulses. Laser-assisted injection is a breakthrough technology that overcomes long-standing limitations associated with traditional method producing high intensity, time structured beams protons in accelerators via use carbon foils injection. The central theme this experiment novel techniques reduce laser power requirement to allow efficiency stripping...
Early fault detection and prognosis are crucial to ensure efficient safe operations of complex engineering systems such as the Spallation Neutron Source (SNS) its power electronics (high voltage converter modulators). Following an advanced experimental facility setup that mimics SNS operating conditions, authors successfully conducted 21 early experiments, where precursors introduced in system a degree enough cause degradation waveform signals, but not reach real fault. Nine different...
XAL is an application programming framework used at the Spallation Neutron Source (SNS) project in Oak Ridge. It written Java, and provides users with a hierarchal view of accelerator. Features include database configuration accelerator structure, online envelope model that configurable from design or live machine values, for quickstart GUI development, scripting interface algorithm common toolkit shared resources. To date, about 25 applications have been written, many which are extensively...
Abstract Through support of the US Department Energy’s Office Basic Energy Sciences, Oak Ridge National Laboratory has begun applying machine learning methods to improve accelerator and target performance Spallation Neutron Source (SNS). These are being applied control optimization power upgrade SNS Cryogenic Moderator System (CMS). A numerical model CMS been developed study these optimizations system modifications using EcosimPro. This paper compares steady-state transient results with...
Abstract Accurate uncertainty estimations are essential for producing reliable machine learning models, especially in safety-critical applications such as accelerator systems. Gaussian process models generally regarded the gold standard this task; however, they can struggle with large, high-dimensional datasets. Combining deep neural networks approximation techniques has shown promising results, but dimensionality reduction through network layers is not guaranteed to maintain distance...
We present a particle core model study of the space charge effect on high intensity synchrotron beams, with specific emphasis Proton Storage Ring (PSR) at Los Alamos National Laboratory. Our formulation includes realistic lattice focusing and dispersion. transport both matched mismatched beams through real structure compare results those an equivalent uniform-focusing approximation. The effects finite momentum spread resonance behavior are specifically targeted. Stroboscopic maps envelope...
Laser-assisted stripping is a novel approach to ${\mathrm{H}}^{\ensuremath{-}}$ charge exchange that overcomes long-standing limitations associated with the traditional, foil-based method of producing high-intensity, time-structured beams protons. This paper reports on first successful demonstration laser technique for microsecond duration beams. The experiment represents factor 1000 increase in stripped pulse compared previous proof-of-principle demonstration. central theme implementation...
The reliability of the mercury spallation target is mission-critical for neutron science program source at Oak Ridge National Laboratory. We present an inverse uncertainty quantification (UQ) study using Bayesian framework equation state model parameters, with assistance polynomial chaos expansion surrogate models. By leveraging high-fidelity structural mechanics simulations and real measured strain data, UQ results reveal a maximum-a-posteriori estimate, mean, standard deviation $6.5\times...
Finding self-consistent distributions of beam particles interacting with each other via the space charge force is one challenges accelerator physics. Exactly solvable models are used for simulation benchmarks, instability threshold calculations, etc. Since such have been found only in and two dimensions (Kapchinsky-Vladimirsky distribution), it not possible to apply them a general three dimensional motion. This paper shows how construct new sets distributions, extending even case.
The LANSCE accelerator is currently powered by a filament-driven, biased converter-type H- ion source that operates at 10%, the highest plasma duty factor for this type of source, using only ∼2.2 SCCM H2. needs to be replaced every 4 weeks, which takes up days. measured negative beam current 12-16 mA falls below desired 24 acceptance LANCSE accelerator. SNS (Spallation Neutron Source) RF-driven, injects ∼50 into 60 Hz with 6% and an availability >99.5% but requires ∼30 Up 7 A h have been...
The Spallation Neutron Source (SNS) accelerator system includes a 65 keV H- injector, 2.5 MeV radio frequency quadrupole (RFQ), 1 GeV linac chain (DTL-CCL-SCL) and an accumulator ring. H− injector consists of RF-driven, Cs-enhanced, multi-cusp ion source compact, two-lens electrostatic low energy beam transport (LEBT). In 2018, new RFQ was installed in place the original along with upgraded support infrastructure. This paper presents operational performance some highlights studies SNS since...
The Cryogenic Moderator System (CMS) is responsible for maintaining a steady flow of cold neutrons numerous physics experiments at the Spallation Neutron Source (SNS) in Oak Ridge National Laboratory (ORNL). Sudden losses beam power, known as trips, cause major disturbance to CMS due large step changes cooling demands. Ongoing efforts on upgrading neutron power from 1.4 2.0MW are expected generate larger transients that can further strain subsystems if they not properly controlled. To manage...
The Oak Ridge Spallation Neutron Source comprises a 1 GeV, 1.5 MW linear accelerator followed by an accumulator ring and liquid mercury target. To manage the beam loss caused ${H}^{0}$ excited states created during ${H}^{\ensuremath{-}}$ charge-exchange injection into ring, stripper foil is located inside one of chicane dipoles. This has some interesting consequences that were not fully appreciated until power reached about 840 kW. One consequence was sudden failure system due to convoy...