Electro- and Photoproduction of Omega(783) Mesons using CLAS at Jefferson Lab

International Nuclear Information System (INIS)

Manak, J.J.; Volker Burkert; Franz Klein; Bernhard Mecking; Alan Coleman; Herb Funsten

2000-01-01

Electro- and photoproduction of w(783) from a proton target have been measured in the CLAS detector at the Thomas Jefferson National Accelerator Facility in Newport News VA. The photoproduction data were taken over a photon energy range from 0.5 to 2.3 GeV, while the electroproduction data was obtained over a W range of 1.8-2.5 GeV/c2. Preliminary acceptance corrected center-of-mass angular distributions have been examined for both data sets

Polarized Electrons at Jefferson Laboratory

Energy Technology Data Exchange (ETDEWEB)

Sinclair, C.K.

1997-12-31

The CEBAF accelerator at Jefferson laboratory can deliver CW electron beams to three experimental halls simultaneously. A large fraction of the approved scientific program at the lab requires polarized electron beams. Many of these experiments, both polarized and unpolarized, require high average beam current as well. Since all electrons delivered to the experimental halls originate from the same cathode, delivery of polarized beam to a single hall requires using the polarized source to deliver beam to all experiments in simultaneous operation. The polarized source effort at Jefferson Lab is directed at obtaining very long polarized source operational lifetimes at high average current and beam polarization; at developing the capability to deliver all electrons leaving the polarized source to the experimental halls; and at delivering polarized beam to multiple experimental halls simultaneously.initial operational experience with the polarized source will be presented.

FOREWORD: Jefferson Lab: A Long Decade of Physics

Science.gov (United States)

Montgomery, Hugh

2011-04-01

Jefferson Lab Jefferson Lab was created in 1984 and started operating in about 1996. 2011 is an appropriate time to try to take a look at the results that have appeared, what has been learned, and what has been exciting for our scientific community. Rather than attempt to construct a coherent view with a single author or at least a small number, we have, instead, invited small groups of people who have been intimately involved in the work itself to make contributions. These people are accelerator experts, experimentalists and theorists, staff and users. We have, in the main, sought reviews of the actual sub-fields. The primary exception is the first paper, which sets the scene as it was, in one person's view, at the beginning of Jefferson Lab. In reviewing the material as it appeared, I was impressed by the breadth of the material. Major advances are documented from form factors to structure functions, from spectroscopy to physics beyond the standard model of nuclear and particle physics. Recognition of the part played by spin, the helicities of the beams, the polarizations of the targets, and the polarizations of final state particles, is inescapable. Access to the weak interaction amplitudes through measurements of the parity violating asymmetries has led to quantification of the strange content of the nucleon and the neutron radius of lead, and to measurements of the electroweak mixing angle. Lattice QCD calculations flourished and are setting the platform for understanding of the spectroscopy of baryons and mesons. But the star of the game was the accelerator. Its performance enabled the physics and also the use of the technology to generate a powerful free electron laser. These important pieces of Jefferson Lab physics are given their place. As the third Director of Jefferson Lab, and on behalf of the other physicists and others presently associated with the lab, I would like to express my admiration and gratitude for the efforts of the directors, chief

Polarized electrons at Jefferson laboratory

International Nuclear Information System (INIS)

Sinclair, C.K.

1998-01-01

The CEBAF accelerator at Jefferson laboratory can deliver CW electron beams to three experimental halls simultaneously. A large fraction of the approved scientific program at the lab requires polarized electron beams. Many of these experiments, both polarized and unpolarized, require high average beam current as well. Since all electrons delivered to the experimental halls originate from the same cathode, delivery of polarized beam to a single hall requires using the polarized source to deliver beam to all experiments in simultaneous operation. The polarized source effort at Jefferson Lab is directed at obtaining very long polarized source operational lifetimes at high average current and beam polarization; at developing the capability to deliver all electrons leaving the polarized source to the experimental halls; and at delivering polarized beam to multiple experimental halls simultaneously. Initial operational experience with the polarized source will be presented. copyright 1998 American Institute of Physics

Jefferson Lab: A Long Decade of Physics

International Nuclear Information System (INIS)

Montgomery, Hugh

2011-01-01

Jefferson Lab was created in 1984 and started operating in about 1996. 2011 is an appropriate time to try to take a look at the results that have appeared, what has been learned, and what has been exciting for our scientific community. Rather than attempt to construct a coherent view with a single author or at least a small number, we have, instead, invited small groups of people who have been intimately involved in the work itself to make contributions. These people are accelerator experts, experimentalists and theorists, staff and users. We have, in the main, sought reviews of the actual sub-fields. The primary exception is the first paper, which sets the scene as it was, in one person's view, at the beginning of Jefferson Lab. In reviewing the material as it appeared, I was impressed by the breadth of the material. Major advances are documented from form factors to structure functions, from spectroscopy to physics beyond the standard model of nuclear and particle physics. Recognition of the part played by spin, the helicities of the beams, the polarizations of the targets, and the polarizations of final state particles, is inescapable. Access to the weak interaction amplitudes through measurements of the parity violating asymmetries has led to quantification of the strange content of the nucleon and the neutron radius of lead, and to measurements of the electroweak mixing angle. Lattice QCD calculations flourished and are setting the platform for understanding of the spectroscopy of baryons and mesons. But the star of the game was the accelerator. Its performance enabled the physics and also the use of the technology to generate a powerful free electron laser. These important pieces of Jefferson Lab physics are given their place. As the third Director of Jefferson Lab, and on behalf of the other physicists and others presently associated with the lab, I would like to express my admiration and gratitude for the efforts of the directors, chief scientists

A composite thin vacuum window for the CLAS photon tagger at Jefferson lab

International Nuclear Information System (INIS)

Matthews, S.K.; Crannell, Hall; O'Brien, J.T.; Sober, D.I.

1999-01-01

The construction of a thin vacuum window, currently in use on the CLAS photon tagging system at the Thomas Jefferson National Accelerator Facility, is described. A layer of woven Kevlar cloth supports a much thinner membrane of aluminized Mylar. Notable features of this particular window include its overall length (9.6 m), and the fact that the entire load is supported by the epoxy seal with no mechanical clamping around the edges. Results from a diverse program of materials testing, including a clear dependence of leak rate on relative humidity, are also reported

A composite thin vacuum window for the CLAS photon tagger at Jefferson lab

CERN Document Server

Matthews, S K; O'Brien, J T; Sober, D I

1999-01-01

The construction of a thin vacuum window, currently in use on the CLAS photon tagging system at the Thomas Jefferson National Accelerator Facility, is described. A layer of woven Kevlar cloth supports a much thinner membrane of aluminized Mylar. Notable features of this particular window include its overall length (9.6 m), and the fact that the entire load is supported by the epoxy seal with no mechanical clamping around the edges. Results from a diverse program of materials testing, including a clear dependence of leak rate on relative humidity, are also reported.

MeV Mott polarimetry at Jefferson Lab

International Nuclear Information System (INIS)

Steigerwald, M.

2001-01-01

In the recent past, Mott polarimetry has been employed only at low electron beam energies (≅100 keV). Shortly after J. Sromicki demonstrated the first Mott scattering experiment on lead foils at 14 MeV (MAMI, 1994), a high energy Mott scattering polarimeter was developed at Thomas Jefferson National Accelerator Facility (5 MeV, 1995). An instrumental precision of 0.5% was achieved due to dramatic improvement in eliminating the background signal by means of collimation, shielding, time of flight and coincidence methods. Measurements for gold targets between 0.05 μm and 5 μm for electron energies between 2 and 8 MeV are presented. A model was developed to explain the depolarization effects in the target foils due to double scattering. The instrumental helicity correlated asymmetries were measured to smaller than 0.1%

PC/104 Embedded IOCs at Jefferson Lab

International Nuclear Information System (INIS)

Yan, Jianxun; Allison, Trent; Witherspoon, Sue; Cuffe, Anthony

2009-01-01

Jefferson Lab has developed embedded IOCs based on PC/104 single board computers (SBC) for low level control systems. The PC/104 IOCs run EPICS on top of the RTEMS operating system. Two types of control system configurations are used in different applications, PC/104 SBC with commercial PC/104 I/O cards and PC/104 SBC with custom designed FPGA-based boards. RTEMS was built with CEXP shell to run on the PC/104 SBC. CEXP shell provides the function of dynamic object loading, which is similar to the widely used VxWorks operating system. Standard software configurations were setup for PC/104 IOC application development to provide a familiar format for new projects as well as ease the conversion of applications from VME based IOCs to PC/104 IOCs. Many new projects at Jefferson Lab are going to employ PC/104 SBCs as IOCs and some applications have already been running them for accelerator operations. The PC/104 - RTEMS IOC provides a free open source Real-Time Operating System (RTOS), low cost/maintenance, easily installed/ configured, flexible, and reliable solution for accelerator control and 12GeV Upgrade projects.

The Jefferson Lab High Power Light Source

Energy Technology Data Exchange (ETDEWEB)

James R. Boyce

2006-01-01

Jefferson Lab has designed, built and operated two high average power free-electron lasers (FEL) using superconducting RF (SRF) technology and energy recovery techniques. Between 1999-2001 Jefferson Lab operated the IR Demo FEL. This device produced over 2 kW in the mid-infrared, in addition to producing world record average powers in the visible (50 W), ultraviolet (10 W) and terahertz range (50 W) for tunable, short-pulse (< ps) light. This FEL was the first high power demonstration of an accelerator configuration that is being exploited for a number of new accelerator-driven light source facilities that are currently under design or construction. The driver accelerator for the IR Demo FEL uses an Energy Recovered Linac (ERL) configuration that improves the energy efficiency and lowers both the capital and operating cost of such devices by recovering most of the power in the spent electron beam after optical power is extracted from the beam. The IR Demo FEL was de-commissioned in late 2001 for an upgraded FEL for extending the IR power to over 10 kW and the ultraviolet power to over 1 kW. The FEL Upgrade achieved 10 kW of average power in the mid-IR (6 microns) in July of 2004, and its IR operation currently is being extended down to 1 micron. In addition, we have demonstrated the capability of on/off cycling and recovering over a megawatt of electron beam power without diminishing machine performance. A complementary UV FEL will come on-line within the next year. This paper presents a summary of the FEL characteristics, user community accomplishments with the IR Demo, and planned user experiments.

Recent skyshine calculations at Jefferson Lab

International Nuclear Information System (INIS)

Degtyarenko, P.

1997-01-01

New calculations of the skyshine dose distribution of neutrons and secondary photons have been performed at Jefferson Lab using the Monte Carlo method. The dose dependence on neutron energy, distance to the neutron source, polar angle of a source neutron, and azimuthal angle between the observation point and the momentum direction of a source neutron have been studied. The azimuthally asymmetric term in the skyshine dose distribution is shown to be important in the dose calculations around high-energy accelerator facilities. A parameterization formula and corresponding computer code have been developed which can be used for detailed calculations of the skyshine dose maps

Survey of electronic safety systems in accelerator applications

International Nuclear Information System (INIS)

Mahoney, K.

1997-01-01

This paper presents the preliminary results and analysis of a comprehensive survey of the implementation of accelerator safety interlock systems from over 30 international labs. At the present time there is not a self consistent means to evaluate both the experiences and level of protection provided by electronic safety interlock systems. This research is intended to analyze the strength and weaknesses of several different types of interlock system implementation methodologies. Research, medical, and industrial accelerators are compared. Thomas Jefferson National Accelerator Facility (TJNAF) was one of the first large particle accelerators to implement a safety interlock system using programmable logic controllers. Since that time all of the major new U.S. accelerator construction projects plan to use some form of programmable electronics as part of a safety interlock system in some capacity

The Jefferson Lab Quality Assurance Program for the SNS Superconducting Linac Construction Project

International Nuclear Information System (INIS)

Joseph Ozelis

2003-01-01

As part of a multi-laboratory collaboration, Jefferson Lab is currently engaged in the fabrication, assembly, and testing of 23 cryomodules for the superconducting linac portion of the Spallation Neutron Source (SNS) being built at Oak Ridge National Laboratory. As with any large accelerator construction project, it is vitally important that these components be built in a cost effective and timely manner, and that they meet the stringent performance requirements dictated by the project specifications. A comprehensive Quality Assurance (QA) program designed to help accomplish these goals has been implemented as an inherent component of JLab's SNS construction effort. This QA program encompasses the traditional spectrum of component performance, from incoming parts inspection, raw materials testing, through to sub-assembly and finished article performance evaluation

Spin observables in charged pion photo-production from polarized neutrons in solid HD at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Kageya, Tsuneo [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Ho, Dao [Carnegie Mellon Univ., Pittsburgh, PA (United States); Peng, Peng [Univ. of Virginia, Charlottesville, VA (United States); Klein, Franz [George Washington Univ., Washington, DC (United States); Sandorfi, Andrew M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Schumacher, Reinhard A. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

2018-04-01

E asymmetries have been extracted from double-polarizationexperiments in Hall-B of the Thomas Jefferson National Accelerator Facility (JLab). Results have been obtained from the E06-101 (g14) experiment, using circularly polarized photon beams, longitudinally polarized Deuterons in solid HD targets, and the CEBAF Large Acceptance Spectrometer (CLAS). The results cover a range inW from 1.48 to 2.32 GeV. Three independent analyses, using distinctly different methods, have been combined to obtain the final values, which have been published recently. Partial wave analyses (PWA), which have had to rely on a sparse neutron data base, havebeen significantly changed with the inclusion of these g14 asymmetries.

Optical modeling of the Jefferson Lab IR Demo FEL

International Nuclear Information System (INIS)

Neil, G.; Benson, S.; Shinn, M.; Davidson, P.; Kloppel, P.

1997-01-01

The Thomas Jefferson National Accelerator Facility (formerly known as CEBAF) has embarked on the construction of a 1 kW free-electron laser operating initially at 3 microns that is designed for laser-material interaction experiments and to explore the feasibility of scaling the system in power and wavelength for industrial and Navy defense applications. The superconducting radio-frequency linac, and single-pass transport which accelerates the beam from injector to wiggler, followed by energy-recovery deceleration to a dump. The electron and optical beam time structure in the design consists of a train of pecosecond pulses at a 37.425 MHz pulse repetition rate. The initial optical configuration is a conventional near-concentric resonator with transmissive outcoupling. Future upgrades of the system will increase the power and shorten the operating wavelength, and utilize a more advanced resonator system capable of scaling to high powers. The optical system of the laser has been mode led using the GLAD code by using a Beer's-law region to mimic the FEL interaction. Effects such as mirror heating have been calculated and compared with analytical treatments. The magnitude of the distorium for several materials and wavelengths has been estimated. The advantages as well as the limitations of this approach are discussed

Jefferson Lab's Distributed Data Acquisition

International Nuclear Information System (INIS)

Trent Allison; Thomas Powers

2006-01-01

Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) occasionally experiences fast intermittent beam instabilities that are difficult to isolate and result in downtime. The Distributed Data Acquisition (Dist DAQ) system is being developed to detect and quickly locate such instabilities. It will consist of multiple Ethernet based data acquisition chassis distributed throughout the seven-eights of a mile CEBAF site. Each chassis will monitor various control system signals that are only available locally and/or monitored by systems with small bandwidths that cannot identify fast transients. The chassis will collect data at rates up to 40 Msps in circular buffers that can be frozen and unrolled after an event trigger. These triggers will be derived from signals such as periodic timers or accelerator faults and be distributed via a custom fiber optic event trigger network. This triggering scheme will allow all the data acquisition chassis to be triggered simultaneously and provide a snapshot of relevant CEBAF control signals. The data will then be automatically analyzed for frequency content and transients to determine if and where instabilities exist

The 12 GeV Upgrade at Jefferson Lab

International Nuclear Information System (INIS)

Rolf Ent

2002-01-01

There has been a remarkable fruitful evolution of our picture of the behavior of strongly interacting matter during the almost two decades that have passed since the parameters of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab were defined. These advances have revealed important new experimental questions best addressed by a CEBAF-class machine at higher energy. Fortunately, favorable technical developments coupled with foresight in the design of the facility make it feasible to triple (double) CEBAF's design (achieved) beam energy from 4 (6) GeV to 12 GeV, in a cost-effective manner: the Upgrade can be realized for about 15% of the cost of the initial facility. This Upgrade would enable the worldwide community to greatly expand its physics horizons. In addition to in general improving the figure of merit and momentum transfer range of the present Jefferson Lab physics program, raising the energy of the accelerator to 12 GeV opens up two main new areas of physics: (1) It allows direct exploration of the quark-gluon structure of hadrons and nuclei in the ''valence quark region''. It is known that inclusive electron scattering at the high momentum and energy transfers available at 12 GeV is governed by elementary interactions with quarks and, indirectly, gluons. The original CEBAF energy is not adequate to study this critical region, while with continuous 12 GeV beams one can cleanly access the entire ''valence quark region'' and exploit the newly discovered Generalized Parton Distributions. In addition, a 12-GeV Jefferson Lab can essentially complete the studies of the transition from hadronic to quark-gluon degrees of freedom. (2) It allows crossing the threshold above which the origins of quark confinement can be investigated. Specifically, 12 GeV will enable the production of certain ''exotic'' mesons. Whereas in the QCD region of asymptotic freedom ample evidence for the role of gluons exist through the observation of gluon jets

Report on the 2005 Particle Accelerator Conference (PAC05)

International Nuclear Information System (INIS)

Kathy F. Rosenbalm

2005-01-01

The 21st Particle Accelerator Conference, PAC05, took place at the Knoxville Convention Center (KCC) from Monday through Friday, May 16-20, 2005. Sponsored by the American Physical Society (APS), the Institute of Electrics and Electronics Engineers (IEEE) with its subdivision of Nuclear and Plasma Sciences Society (NPSS), the conference was hosted by the Oak Ridge National Laboratory (ORNL) Spallation Neutron Source (SNS) Project and Thomas Jefferson National Accelerator Facility (JLab). The conference was chaired by Norbert Holtkamp, and the Local Organizing Committee was made up of staff from the ORNL SNS Project under the chairmanship of Stuart Henderson. The conference welcomed over 1400 delegates from the United States, Europe, Asia, the Middle East, South America and from as far away as Australia. Almost 1400 papers where processed during the conference and will be published on the Joint Accelerator Conferences Website (JACoW) page

NEW EPICS/RTEMS IOC BASED ON ALTERA SOC AT JEFFERSON LAB

Energy Technology Data Exchange (ETDEWEB)

Yan, Jianxun [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Seaton, Chad [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Allison, Trent L. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Bevins, Brian S. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Cuffe, Anthony W. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2018-02-01

A new EPICS/RTEMS IOC based on the Altera System-on-Chip (SoC) FPGA is being designed at Jefferson Lab. The Altera SoC FPGA integrates a dual ARM Cortex-A9 Hard Processor System (HPS) consisting of processor, peripherals and memory interfaces tied seamlessly with the FPGA fabric using a high-bandwidth interconnect backbone. The embedded Altera SoC IOC has features of remote network boot via U-Boot from SD card or QSPI Flash, 1Gig Ethernet, 1GB DDR3 SDRAM on HPS, UART serial ports, and ISA bus interface. RTEMS for the ARM processor BSP were built with CEXP shell, which will dynamically load the EPICS applications at runtime. U-Boot is the primary bootloader to remotely load the kernel image into local memory from a DHCP/TFTP server over Ethernet, and automatically run RTEMS and EPICS. The first design of the SoC IOC will be compatible with Jefferson Lab’s current PC104 IOCs, which have been running in CEBAF 10 years. The next design would be mounting in a chassis and connected to a daughter card via standard HSMC connectors. This standard SoC IOC will become the next generation of low-level IOC for the accelerator controls at Jefferson Lab.

National software infrastructure for lattice gauge theory

International Nuclear Information System (INIS)

Brower, Richard C

2005-01-01

The current status of the SciDAC software infrastructure project for lattice gauge theory is summarized. This includes the the design of a QCD application programmers interface (API) that allows existing and future codes to be run efficiently on Terascale hardware facilities and to be rapidly ported to new dedicated or commercial platforms. The critical components of the API have been implemented and are in use on the US QCDOC hardware at BNL and on both the switched and mesh architecture Pentium 4 clusters at Fermi National Accelerator Laboratory (FNAL) and Thomas Jefferson National Accelerator Facility (JLab). Future software infrastructure requirements and research directions are also discussed

The CLAS12 Torus Detector Magnet at Jefferson Laboratory

Energy Technology Data Exchange (ETDEWEB)

Luongo, Cesar [Jefferson Lab; Ballard, Joshua [Jefferson Lab; Biallas, George [Jefferson Lab; Elouadrhiri, Latifa [Jefferson Lab; Fair, Ruben [Jefferson Lab; Ghoshal, Probir [Jefferson Lab; Kashy, Dave [Jefferson Lab; Legg, Robert [Jefferson Lab; Pastor, Orlando [Jefferson Lab; Rajput-Ghoshal, Renuka [Jefferson Lab; Rode, Claus [Jefferson Lab; Wiseman, Mark [Jefferson Lab; Young, Glenn [Jefferson Lab; Elementi, Luciano [Fermilab; Krave, Steven [Fermilab; Makarov, Alexander [Fermilab; Nobrega, Fred [Fermilab; Velev, George [Fermilab

2015-12-17

The CLAS12 Torus is a toroidal superconducting magnet, which is part of the detector for the 12-GeV accelerator upgrade at Jefferson Laboratory (JLab). The coils were wound/fabricated by Fermilab, with JLab responsible for all other parts of the project scope, including design, integration, cryostating the individual coils, installation, cryogenics, I&C, etc. This paper provides an overview of the CLAS12 Torus magnet features and serves as a status report of its installation in the experimental hall. Completion and commissioning of the magnet is expected in 2016.

High luminosity operation of large solid angle scintillator arrays in Jefferson Lab Hall A

International Nuclear Information System (INIS)

Ran Shneor

2003-01-01

This thesis describes selected aspects of high luminosity operation of large solid angle scintillator arrays in Hall A of the CEBAF (Central Electron Beam Accelerator Facility) at TJNAF (Thomas Jefferson National Accelerator Facility ). CEBAF is a high current, high duty factor electron accelerator with a maximum beam energy of about 6 GeV and a maximum current of 200 (micro)A. Operating large solid angle scintillator arrays in high luminosity environment presents several problems such as high singles rates, low signal to noise ratios and shielding requirements. To demonstrate the need for large solid angle and momentum acceptance detectors as a third arm in Hall A, we will give a brief overview of the physics motivating five approved experiments, which utilize scintillator arrays. We will then focus on the design and assembly of these scintillator arrays, with special focus on the two new detector packages built for the Short Range Correlation experiment E01-015. This thesis also contains the description and results of different tests and calibrations which where conducted for these arrays. We also present the description of a number of tests which were done in order to estimate the singles rates, data reconstruction, filtering techniques and shielding required for these counters

Thomas Jefferson's Academical Village

DEFF Research Database (Denmark)

Foote, Jonathan; Frohburg, Jan

2017-01-01

This is an essay written for the Festschrift of Karl-Heinz Schmitz, Professor at Bauhaus-Universität Weimar. It reflects on some aspects of Thomas Jefferson's design for the University of Virginia in relation to Professor's Schmitz' teachings and interests.......This is an essay written for the Festschrift of Karl-Heinz Schmitz, Professor at Bauhaus-Universität Weimar. It reflects on some aspects of Thomas Jefferson's design for the University of Virginia in relation to Professor's Schmitz' teachings and interests....

Recent Measurements from the G0 Parity Violation Experiment Carried out at Jefferson Laboratory

International Nuclear Information System (INIS)

Bimbot, L.

2008-01-01

The measurements were made at the Thomas Jefferson National Accelerator Facility (J Lab.), Newport News, V A (USA) in the backward angle configuration set-up. A toroidal spectrometer, associated with particle detectors, is used to count electrons and pions from a liquid hydrogen or deuterium target. Parity-violating than the former one by orders of magnitude and requires special techniques to be observed and isolated. Parity violation is specific to the electro-weak interaction and forms the basis asymmetries in elastic electron-proton scattering are determined for momentum transfers of Q 2 = 0.62 and 0.23 (GeV/c) 2 . Combined with previous results obtained with the forward angle configuration setup, these measurements give access to the separation of the values of electric and magnetic strange form factors of the proton. More results may be extracted from the asymmetries for inelastically scattered electrons and for produced pions

CEBAF Accelerator Achievements

International Nuclear Information System (INIS)

Chao, Y C; Drury, M; Hovater, C; Hutton, A; Krafft, G A; Poelker, M; Reece, C; Tiefenback, M

2011-01-01

In the past decade, nuclear physics users of Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) have benefited from accelerator physics advances and machine improvements. As of early 2011, CEBAF operates routinely at 6 GeV, with a 12 GeV upgrade underway. This article reports highlights of CEBAF's scientific and technological evolution in the areas of cryomodule refurbishment, RF control, polarized source development, beam transport for parity experiments, magnets and hysteresis handling, beam breakup, and helium refrigerator operational optimization.

GlueX: The Search for Gluonic Excitations at Jefferson Laboratory

Energy Technology Data Exchange (ETDEWEB)

D.S. Carman

2005-08-21

One of the unanswered and most fundamental questions in physics regards the nature of the confinement mechanism of quarks and gluons in quantum chromodynamics (QCD). Exotic hybrid mesons manifest gluonic degrees of freedom and their detailed spectroscopy will provide the precision data necessary to test assumptions in lattice QCD and the specific phenomenology leading to confinement. Photoproduction is expected to be a particularly effective manner to produce exotic hybrids, however, existing data using photon beams are sparse. At Jefferson Laboratory, plans are underway by the GlueX Collaboration to use the coherent bremsstrahlung technique to produce a linearly polarized photon beam. A solenoid-based hermetic detector will be used to collect data on meson production and decays with statistics that will exceed existing photoproduction data by several orders of magnitude after the first year of running. In order to reach the ideal photon energy of 9 GeV required for these studies, the energy of the Jefferson Laboratory electron accelerator, CEBAF, will be doubled from its current maximum energy of 6 GeV to 12 GeV. The physics motivating the search and the status of the project are reviewed.

The Brookhaven National Laboratory Accelerator Test Facility

International Nuclear Information System (INIS)

Batchelor, K.

1992-01-01

The Brookhaven National Laboratory Accelerator Test Facility comprises a 50 MeV traveling wave electron linear accelerator utilizing a high gradient, photo-excited, raidofrequency electron gun as an injector and an experimental area for study of new acceleration methods or advanced radiation sources using free electron lasers. Early operation of the linear accelerator system including calculated and measured beam parameters are presented together with the experimental program for accelerator physics and free electron laser studies

RICH Detector for Jefferson Labs CLAS12

Science.gov (United States)

Trotta, Richard; Torisky, Ben; Benmokhtar, Fatiha

2015-10-01

Jefferson Lab (Jlab) is performing a large-scale upgrade to its Continuous Electron Beam Accelerator Facility (CEBAF) up to 12GeV beams. The Large Acceptance Spectrometer (CLAS12) in Hall B is being upgraded and a new hybrid Ring Imaging Cherenkov (RICH) detector is being developed to provide better kaon - pion separation throughout the 3 to 8 GeV/c momentum range. This detector will be used for a variety of Semi-Inclusive Deep Inelastic Scattering experiments. Cherenkov light can be accurately detected by a large array of sophisticated Multi-Anode Photomultiplier Tubes (MA-PMT) and heavier particles, like kaons, will span the inner radii. We are presenting our work on the creation of the RICH's geometry within the CLAS12 java framework. This development is crucial for future calibration, reconstructions and analysis of the detector.

Residual Resistance Data from Cavity Production Projects at Jefferson Lab

International Nuclear Information System (INIS)

Ciovati, Gianluigi; Geng, Rongli; Mammosser, John; Saunders, Jeffrey

2010-01-01

A fundamental limitation towards achieving high quality factors in superconducting radio-frequency cavities is the so-called residual resistance. Understanding and controlling the residual resistance has important implications towards improving the efficiency and reduce the operating cost of continuous wave superconducting linear accelerators. In this contribution we will report on the residual resistance values obtained from measurements of the quality factor of a large set of cavities, with resonant frequency between 805 MHz and 1.5 GHz, all of them processed and tested at Jefferson Lab. Surface treatments included both buffered chemical polishing and electropolishing. The results indicate an approximate value of the residual resistance of about 7-10 n Omega.

The Complexity of Thomas Jefferson. A Response to "'The Diffusion of Light': Jefferson's Philosophy of Education"

Science.gov (United States)

Carpenter, James

2014-01-01

This response argues that Jefferson's educational philosophy must be considered in a proper historical context. Holowchak accurately demonstrates both Jefferson's obsession with education and the political philosophy on which his educational beliefs are built. However, the effort to apply modern democratic and meritocratic attributes to…

Evolution of the Generic Lock System at Jefferson Lab

International Nuclear Information System (INIS)

Brian Bevins; Yves Roblin

2003-01-01

The Generic Lock system is a software framework that allows highly flexible feedback control of large distributed systems. It allows system operators to implement new feedback loops between arbitrary process variables quickly and with no disturbance to the underlying control system. Several different types of feedback loops are provided and more are being added. This paper describes the further evolution of the system since it was first presented at ICALEPCS 2001 and reports on two years of successful use in accelerator operations. The framework has been enhanced in several key ways. Multiple-input, multiple-output (MIMO) lock types have been added for accelerator orbit and energy stabilization. The general purpose Proportional-Integral-Derivative (PID) locks can now be tuned automatically. The generic lock server now makes use of the Proxy IOC (PIOC) developed at Jefferson Lab to allow the locks to be monitored from any EPICS Channel Access aware client. (Previously clients had to be Cdev aware.) The dependency on the Qt XML parser has been replaced with the freely available Xerces DOM parser from the Apache project

Hurricane Isabel gives accelerators a severe test

International Nuclear Information System (INIS)

Swapan Chattopadhyay

2004-01-01

Hurricane Isabel was at category five--the most violent on the Saffir-Simpson scale of hurricane strength--when it began threatening the central Atlantic seaboard of the US. Over the course of several days, precautions against the extreme weather conditions were taken across the Jefferson Lab site in south-east Virginia. On 18 September 2003, when Isabel struck North Carolina's Outer Banks and moved northward, directly across the region around the laboratory, the storm was still quite destructive, albeit considerably reduced in strength. The flood surge and trees felled by wind substantially damaged or even devastated buildings and homes, including many belonging to Jefferson Lab staff members. For the laboratory itself, Isabel delivered an unplanned and severe challenge in another form: a power outage that lasted nearly three-and-a-half days, and which severely tested the robustness of Jefferson Lab's two superconducting machines, the Continuous Electron Beam Accelerator Facility (CEBAF) and the superconducting radiofrequency ''driver'' accelerator of the laboratory's free-electron laser. Robustness matters greatly for science at a time when microwave superconducting linear accelerators (linacs) are not only being considered, but in some cases already being built for projects such as neutron sources, rare-isotope accelerators, innovative light sources and TeV-scale electron-positron linear colliders. Hurricane Isabel interrupted a several-week-long maintenance shutdown of CEBAF, which serves nuclear and particle physics and represents the world's pioneering large-scale implementation of superconducting radiofrequency (SRF) technology. The racetrack-shaped machine is actually a pair of 500-600 MeV SRF linacs interconnected by recirculation arc beamlines. CEBAF delivers simultaneous beams at up to 6 GeV to three experimental halls. An imminent upgrade will double the energy to 12 GeV and add an extra hall for ''quark confinement'' studies. On a smaller scale

12 GeV detector technology at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Leckey, John P. [Indiana University, Bloomington, IN 47405 (United States); Collaboration: GlueX Collaboration

2013-04-19

The Thomas Jefferson National Accelerator Facility (JLab) is presently in the middle of an upgrade to increase the energy of its CW electron beam from 6 GeV to 12 GeV along with the addition of a fourth experimental hall. Driven both by necessity and availability, novel detectors and electronics modules have been used in the upgrade. One such sensor is the Silicon Photomultiplier (SiPM), specifically a Multi-Pixel Photon Counter (MPPC), which is an array of avalanche photodiode pixels operating in Geiger mode that are used to sense photons. The SiPMs replace conventional photomultiplier tubes and have several distinct advantages including the safe operation in a magnetic field and the lack of need for high voltage. Another key to 12 GeV success is advanced fast electronics. Jlab will use custom 250 MHz and 125 MHz 12-bit analog to digital converters (ADCs) and time to digital converters (TDCs) all of which take advantage of VME Switched Serial (VXS) bus with its GB/s high bandwidth readout capability. These new technologies will be used to readout drift chambers, calorimeters, spectrometers and other particle detectors at Jlab once the 12 GeV upgrade is complete. The largest experiment at Jlab utilizing these components is GlueX - an experiment in the newly constructed Hall D that will study the photoproduction of light mesons in the search for hybrid mesons. The performance of these components and their respective detectors will be presented.

Accelerator timing at Brookhaven National Laboratory

International Nuclear Information System (INIS)

Oerter, B.; Conkling, C.R.

1995-01-01

Accelerator timing at Brookhaven National Laboratory has evolved from multiple coaxial cables transmitting individual pulses in the original Alternating Gradient Synchrotron (AGS) design, to serial coded transmission as the AGS Booster was added. With the implementation of this technology, the Super Cycle Generator (SCG) which synchronizes the AGS, Booster, LINAC, and Tandem accelerators was introduced. This paper will describe the timing system being developed for the Relativistic Heavy Ion Collider (RHIC)

Digital Data for Volcano Hazards in the Mount Jefferson Region, Oregon

Science.gov (United States)

Schilling, S.P.; Doelger, S.; Walder, J.S.; Gardner, C.A.; Conrey, R.M.; Fisher, B.J.

2008-01-01

Mount Jefferson has erupted repeatedly for hundreds of thousands of years, with its last eruptive episode during the last major glaciation which culminated about 15,000 years ago. Geologic evidence shows that Mount Jefferson is capable of large explosive eruptions. The largest such eruption occurred between 35,000 and 100,000 years ago. If Mount Jefferson erupts again, areas close to the eruptive vent will be severely affected, and even areas tens of kilometers (tens of miles) downstream along river valleys or hundreds of kilometers (hundreds of miles) downwind may be at risk. Numerous small volcanoes occupy the area between Mount Jefferson and Mount Hood to the north, and between Mount Jefferson and the Three Sisters region to the south. These small volcanoes tend not to pose the far-reaching hazards associated with Mount Jefferson, but are nonetheless locally important. A concern at Mount Jefferson, but not at the smaller volcanoes, is the possibility that small-to-moderate sized landslides could occur even during periods of no volcanic activity. Such landslides may transform as they move into lahars (watery flows of rock, mud, and debris) that can inundate areas far downstream. The geographic information system (GIS) volcano hazard data layer used to produce the Mount Jefferson volcano hazard map in USGS Open-File Report 99-24 (Walder and others, 1999) is included in this data set. Both proximal and distal hazard zones were delineated by scientists at the Cascades Volcano Observatory and depict various volcano hazard areas around the mountain.

Nuclear power and the Hamilton-Jefferson debate

International Nuclear Information System (INIS)

Hacker, A.

1980-01-01

The basic sources of nuclear opposition derive from the philosophical arguments of Thomas Jefferson against Alexander Hamilton's vision of an industrial society with a strong central authority. Today's young people continue Jefferson's radical plea for the individual freedoms associated with personal ownership and limited government, but they accept the structure of the former while searching for the romanticism of the latter. The nuclear debate reflects this dichotomy and will continue even if the issues of waste disposal and safety are resolved

Nuclear power and the Hamilton-Jefferson debate

Energy Technology Data Exchange (ETDEWEB)

Hacker, A.

The basic sources of nuclear opposition derive from the philosophical arguments of Thomas Jefferson against Alexander Hamilton's vision of an industrial society with a strong central authority. Today's young people continue Jefferson's radical plea for the individual freedoms associated with personal ownership and limited government, but they accept the structure of the former while searching for the romanticism of the latter. The nuclear debate reflects this dichotomy and will continue even if the issues of waste disposal and safety are resolved. (DCK)

The 4th Generation Light Source at Jefferson Lab

International Nuclear Information System (INIS)

Stephen Benson; George Biallas; James Boyce; Donald Bullard; James Coleman; David Douglas; H. Dylla; Richard Evans; Pavel Evtushenko; Albert Grippo; Christopher Gould; Joseph Gubeli; David Hardy; Carlos Hernandez-Garcia; Kevin Jordan; John Klopf; Steven Moore; George Neil; Thomas Powers; Joseph Preble; Daniel Sexton; Michelle Shinn; Christopher Tennant; Richard Walker; Shukui Zhang; Gwyn Williams

2007-01-01

A number of 'Grand Challenges' in Science have recently been identified in reports from The National Academy of Sciences, and the U.S. Dept. of Energy, Basic Energy Sciences. Many of these require a new generation of linac-based light source to study dynamical and non-linear phenomena in nanoscale samples. In this paper we present a summary of the properties of such light sources, comparing them with existing sources, and then describing in more detail a specific source at Jefferson Lab. Importantly, the JLab light source has developed some novel technology which is a critical enabler for other new light sources

Deeply virtual Compton scattering in the Hall A of Jefferson laboratory; Diffusion Compton profondement virtuelle dans le Hall A au Jefferson laboratory

Energy Technology Data Exchange (ETDEWEB)

Munoz Camacho, C

2005-12-15

Generalized Parton Distributions (GPDs), introduced in the late 90's, provide a universal description of hadrons in terms of the underlying degrees of freedom of Quantum Chromodynamics: quarks and gluons. GPDs appear in a wide variety of hard exclusive reactions and the advent of high luminosity accelerator facilities has made the study of GPDs accessible to experiment. Deeply Virtual Compton Scattering (DVCS) is the golden process involving GPDs. The first dedicated DVCS experiment ran in the Hall A of Jefferson Lab in Fall 2004. An electromagnetic calorimeter and a plastic scintillator detector were constructed for this experiment, together with specific electronics and acquisition system. The experiment preparation, data taking and analysis are described in this document. Results on the absolute cross section difference for opposite beam helicities provide the first measurement of a linear combination of GPDs as a function of the momentum transfer to the nucleon. (author)

National Computational Infrastructure for Lattice Gauge Theory: Final report

International Nuclear Information System (INIS)

Reed, Daniel A.

2008-01-01

In this document we describe work done under the SciDAC-1 Project National Computerational Infrastructure for Lattice Gauge Theory. The objective of this project was to construct the computational infrastructure needed to study quantum chromodynamics (QCD). Nearly all high energy and nuclear physicists in the United States working on the numerical study of QCD are involved in the project, as are Brookhaven National Laboratory (BNL), Fermi National Accelerator Laboratory (FNAL), and Thomas Jefferson National Accelerator Facility (JLab). A list of the senior participants is given in Appendix A.2. The project includes the development of community software for the effective use of the terascale computers, and the research and development of commodity clusters optimized for the study of QCD. The software developed as part of this effort is publicly available, and is being widely used by physicists in the United States and abroad. The prototype clusters built with SciDAC-1 fund have been used to test the software, and are available to lattice gauge theorists in the United States on a peer reviewed basis

How accelerator operations does business at Jefferson Lab

International Nuclear Information System (INIS)

Green, David W. Jr.

2004-01-01

The accelerator is staffed 24 hours a day by the MCC Operations Group. Shift rotations are for seven days on shift, followed by seven days off shift, of which three days are spent on off-shift activities. Personnel spend 70% of their time on shift and 30% off shift. The off-shift time is utilized for meetings, training and individual projects. Individual projects can consist of hardware or software development, training, documentation development or other areas of interest, depending on the individual. (author)

Electromagnetic calorimeter for the Heavy Photon Search Experiment at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Buchanan, Emma [Univ. of Glasgow, Scotland (United Kingdom)

2014-11-01

The Heavy Photon Search Experiment (HPS) seeks to detect a hypothesised hidden sector boson, the A', predicted to be produced in dark matter decay or annihilation. Theories suggest that the A' couples weakly to electric charge through kinetic mixing, allowing it, as a result, to decay to Standard Matter (SM) lepton pair, which may explain the electron and positron excess recently observed in cosmic rays. Measuring the lepton pair decay of the A' could lead to indirect detection of dark matter. The HPS experiment is a fixed target experiment that will utilize the electron beam produced at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). The detector set-up includes a silicon vertex tracker (SVT) and an Electromagnetic Calorimeter (ECal). The ECal will provide the trigger and detect e+e- pairs and its construction and testing forms the focus of this thesis. The ECal consists of 442 PbWO₄- tapered crystals with a length 16cm and a 1.6x1.6cm² cross-section, stacked into a rectangular array and are coupled to Large Area APDs and corresponding pre-amplifiers. Supplementary to the ECal is a Light Monitoring System (LMS) consisting of bi-coloured LEDs that will monitor changes in APD gain and crystal transparency due to radiation damage. Before construction of the ECal each of the components were required to be individually tested to determine a number of different characteristics. Irradiation tests were performed on PbWO₄ ECal crystals and, as a comparison, one grown by a different manufacturer to determine their radiation hardness. A technique for annealing the radiation damage by optical bleaching, which involves injecting light of various wavelengths into the crystal, was tested using the blue LED from the LMS as a potential candidate. The light yield dependence on temperature was also measured for one of the PbWO₄ crystal types. Each APD was individually tested to determine if they

The Qweakp experiment at Jefferson Laboratory

International Nuclear Information System (INIS)

Page, Shelley

2008-01-01

A major new experiment is being prepared at Jefferson Laboratory to measure the proton's weak charge via the parity violating asymmetry in elastic electron-proton scattering at very low momentum transfer. The Standard Model makes a firm prediction of the proton' weak charge, Q w p = 1 - 4 sin2thetaW, based on the running of the weak mixing angle sin2thetaW from the Z 0 pole down to low energies, corresponding to a 10sigma effect in our experiment. Our ultimate goal is to determine the proton' weak charge with 4% combined statistical and systematic errors, which in turn leads to a 0.3% measurement of sin2 thetaW. The experiment is currently under construction; installation in Hall C at Jefferson Lab followed by data taking is planned for 2009.

The Jefferson Lab Trigger Supervisor System

International Nuclear Information System (INIS)

Ed Jastrzembsi; David Abbott; Graham Heyes; R.W. MacLeod; Carl Timmer; Elliott Wolin

2000-01-01

We discuss the design and performance of a Trigger Supervisor System for use in nuclear physics experiments at Jefferson Lab. We also discuss the enhanced features of a new Trigger Supervisor Module now under construction

The Jefferson Lab Trigger Supervisor System

International Nuclear Information System (INIS)

Jastrzembski, E.; Abbott, D.J.; Heyes, W.G.; MacLeod, R.W.; Timmer, C.; Wolin, E.

1999-01-01

The authors discuss the design and performance of a Trigger Supervisor System for use in nuclear physics experiments at Jefferson Lab. They also discuss the enhanced features of a new Trigger Supervisor Module now under construction

First experimental data on the FEL - RF interaction at the Jefferson Lab IRFEL

International Nuclear Information System (INIS)

L. Merminga; P. Alexeev; S.V. Benson; A. Bolshakov; L.R. Doolittle; D.R. Douglas; C. Hovater; G.R. Neil

1999-01-01

High power FELs driven by recirculating, energy-recovering linacs can exhibit instabilities in the beam energy and laser output power. Fluctuations in the accelerating cavity fields can cause beam loss on apertures, phase oscillations and optical cavity detuning. These can affect the laser power and in turn the beam-induced voltage to further enhance the fluctuations of the rf fields. A theoretical model was developed to study the dynamics of the coupled system and was presented last year. Recently, a first set of experimental data was obtained at the Jefferson Lab IRFEL for direct comparisons with the model. The authors describe the experiment, present the data together with the modeling predictions and outline future directions

A Magnetorestrictive Tuning System for Particle Accelerators

Energy Technology Data Exchange (ETDEWEB)

Chiu-Ying Tai; Jordan Cormier; William Espinola; Zhixiu Han; Chad Joshi; Anil Mavanur; Livia Racz; Kenneth Shepard; Edward Daly; Kirk Davis

2005-05-16

Energen, Inc. has designed, built, and demonstrated several fast and slow tuners based on its magnetostrictive actuators and stepper motor. These tuners are designed for Superconducting Radio Frequency (SRF) cavities, which are important structures in particle accelerators that support a wide spectrum of disciplines, including nuclear and high-energy physics and free electron lasers (FEL). In the past two years, Energen's work has focused on magnetostrictive fast tuners for microphonics and Lorentz detuning compensation on elliptical-cell and spoke-loaded cavities. These tuners were custom designed to meet specific requirements, which included a few to 100 micron stroke range, hundreds to kilohertz operation frequency, and cryogenic temperature operation in vacuum or liquid helium. These tuners have been tested in house and at different laboratories, such as DESY, Argonne National Lab, and Jefferson Lab. Some recent results are presented in this paper.

Present and future of hadron spectroscopy at Jefferson Lab

CERN Document Server

Battaglieri, M

2010-01-01

The CLAS Collaboration is operating the CLAS detector at theThomas Jefferson National Laboratory (JLab) in USA. The unique combination of the detector large acceptance and high intensity of the continuous electron beam of CEBAF has opened the way to a comprehensive study of the hadrons structure in kinematic domain between nuclear and particle physics. Hadron spectroscopy plays a central role in the physics program of the Collaboration. Many exclusive channels have been studied with virtual and real photon beams in a wide kinematic providing key information about the hadron structure as well as the reactions dynamic. In this contribution, the rich physics program covered by present and future experiments will be reviewed.

Determination of the Optimal Operating Parameters for the Jefferson Lab's Cryogenic Cold Compressor System

International Nuclear Information System (INIS)

Joe Wilson; Venkatarao Ganni; Dana Arenius; Jonathan Creel

2004-01-01

Jefferson Lab's (JLab) Continuous Electron Beam Accelerator Facility (CEBAF) and Free Electron Laser (FEL) are supported by 2 K helium refrigerator known as the Central Helium Liquefier (CHL), which maintains a constant low vapor pressure over the accelerators' large liquid helium inventory with a five-stage centrifugal compressor train. The cold compressor train operates with constrained discharge pressure and can be varied over a range of suction pressures and mass flows to meet the operational requirements of the two accelerators. Using data from commissioning and routine operations of the cold compressor system, the presented procedure predicts an operating point for each cold compressor such that maximum efficiency is attained for the overall cold compressor system for a given combination of mass flow and vapor pressure. The procedure predicts expected efficiency of the system and relative compressors speeds for operating vapor pressures from 4 to 2.5 kPa (corresponds to overall pressure ratios of 29 to 56) and flow rates of 135 g/s to 250 g/s. The results of the predictions are verified by test for a few operating conditions of mass flows and vapor pressures

An Overview of Dark Matter Experiments at Jefferson Lab

International Nuclear Information System (INIS)

Boyce, James R

2012-01-01

Dark Matter research at Jefferson Lab started in 2006 with the LIght Pseudoscalar and Scalar Search (LIPSS) collaboration to check the validity of results reported by the PVLAS collaboration. In the intervening years interest in dark matter laboratory experiments has grown at Jefferson Lab. Current research underway or in planning stages probe various mass regions covering 14 orders of magnitude: from 10 −6 eV to 100 MeV. This presentation will be an overview of our dark matter searches, three of which focus on the hypothesized A' gauge boson.

Become Jefferson in cyberspace

Directory of Open Access Journals (Sweden)

Ryszard Tadeusiewicz

2010-01-01

Full Text Available Very newly defined, but fast developing area of e-learning practice, is now known and available for everybody. Therefore it not need more explorers. Most of fundamental facts and properties are discovered and practical “colonization” of such area is already done. But the new area of practical activities of many e-learning specialists need now rules and regulations. Therefore we not need new Columbus of Cyberspace, but Jefferson of Cyberspace is necessary just now!

A Magnetostrictive Tuning System for Particle Accelerators

CERN Document Server

Tai, Chiu-Ying; Daly, Edward; Davis, Kirk; Espinola, William; Han, Zhixiu; Joshi, Chandrashekhar; Mavanur, Anil; Racz, Livia; Shepard, Kenneth

2005-01-01

Energen, Inc. has designed, built, and demonstrated several fast and slow tuners based on its magnetostrictive actuators and stepper motor. These tuners are designed for Superconducting Radio Frequency (SRF) cavities, which are important structures in particle accelerators that support a wide spectrum of disciplines, including nuclear and high-energy physics and free electron lasers (FEL). In the past two years, Energen's work has focused on magnetostrictive fast tuners for microphonics and Lorentz detuning compensation on elliptical-cell and spoke-loaded cavities, including the capability for real-time closed-loop control. These tuners were custom designed to meet specific requirements, which included a few to 100 micron stroke range, hundreds to kilohertz operation frequency, and cryogenic temperature operation in vacuum or liquid helium. These tuners have been tested in house and at different laboratories, such as DESY, Argonne National Lab, and Jefferson Lab. Some recent results are presented in this pape...

Proceedings of the 1. national meeting on accelerators

International Nuclear Information System (INIS)

Aguilera, E.F.

1989-01-01

The document includes 12 invited papers presented at the 1. National meeting on accelerators held between 25-26 May 1989 in Salazar (Mexico) . A separate abstract was prepared for each of these papers

Thomas Jefferson and the Purposes of Education.

Science.gov (United States)

Jewett, Thomas O.

1997-01-01

Thomas Jefferson was the first conspicuous U.S. advocate of free education supported by local taxation and of state aid to higher education. He believed that only an educated citizenry could assume the responsibilities of self-government. (SK)

Deeply virtual Compton scattering in the Hall A of Jefferson laboratory

International Nuclear Information System (INIS)

Munoz Camacho, C.

2005-12-01

Generalized Parton Distributions (GPDs), introduced in the late 90's, provide a universal description of hadrons in terms of the underlying degrees of freedom of Quantum Chromodynamics: quarks and gluons. GPDs appear in a wide variety of hard exclusive reactions and the advent of high luminosity accelerator facilities has made the study of GPDs accessible to experiment. Deeply Virtual Compton Scattering (DVCS) is the golden process involving GPDs. The first dedicated DVCS experiment ran in the Hall A of Jefferson Lab in Fall 2004. An electromagnetic calorimeter and a plastic scintillator detector were constructed for this experiment, together with specific electronics and acquisition system. The experiment preparation, data taking and analysis are described in this document. Results on the absolute cross section difference for opposite beam helicities provide the first measurement of a linear combination of GPDs as a function of the momentum transfer to the nucleon. (author)

Neutron Arm Study and Calibration for the GEn Experiment at Thomas Jefferson National Laboratory

International Nuclear Information System (INIS)

Timothy Ngo

2007-01-01

The measurement of the neutron electric form factor, GEn, will allow us to solve indirectly for the quark charge distribution inside of the neutron. With the equipment at Jefferson Lab we have measured GEn at four momentum transfer values of Q**2 at 1.3, 2.4 and 3.4 (GeV/c)**2 using a polarized electron beam and polarized Helium target. The scattered electrons off of the Helium target are detected in the BigBite spectrometer and the recoiling neutrons from the Helium are detected in the Neutron Arm, which is composed of an array of scintillators. The main focus of this thesis will be devoted to the geometry, timing and energy calibrations of the Neutron Arm

An overview of the user program for the Jefferson Lab free electron laser

International Nuclear Information System (INIS)

Dylla, H.F.

1999-01-01

Jefferson Lab is commissioning a high-average-power IR FEL during 1998. When driven with its superconducting linac operating in a recirculated mode, the IR Demo FEL is capable of producing kilowatt-level average power in the mid-infrared (2-7 mu m) range. With operational experience and hardware changes involving primarily change-out of the optical cavity mirrors, the FEL is capable of covering a wide range of the infrared (1-16 mu m) at power levels exceeding 100 W. This tuning range combined with a unique pulse structure makes the Jefferson Lab FEL a versatile research and development tool for a wide variety of laser applications. A core group of industrial partners has been involved in planning applications using the FEL since 1991. This initial user group was augmented with university partners in 1993 and with participants from several national laboratories in 1996-1997. With the initiation of construction of the FEL and the associated 600 m 2 user facility laboratory in 1996, a number of topical user groups were formed to plan and implement the first series of user experiments. The industrial partners have formed user groups planning applications in polymer surface processing, metal surface processing, microfabrication, and electronic materials. University partners have submitted proposals on basic science topics which complement and planned applied research topics, in addition to proposing experiments in atomic physics, chemical physics and materials science which take advantage of one or more of the unique characteristics of the FEL. A synopsis of the proposed user experiments for the first phase of operation of the Jefferson Lab FEL will be presented

Pulsed-focusing recirculating linacs for muon acceleration

Energy Technology Data Exchange (ETDEWEB)

Johnson, Rolland [Muons, Inc., Batavia, IL (United States)

2014-12-31

Since the muon has a short lifetime, fast acceleration is essential for high-energy applications such as muon colliders, Higgs factories, or neutrino factories. The best one can do is to make a linear accelerator with the highest possible accelerating gradient to make the accelerating time as short as possible. However, the cost of such a single linear accelerator is prohibitively large due to expensive power sources, cavities, tunnels, and related infrastructure. As was demonstrated in the Thomas Jefferson Accelerator Facility (Jefferson Lab) Continuous Electron Beam Accelerator Facility (CEBAF), an elegant solution to reduce cost is to use magnetic return arcs to recirculate the beam through the accelerating RF cavities many times, where they gain energy on each pass. In such a Recirculating Linear Accelerator (RLA), the magnetic focusing strength diminishes as the beam energy increases in a conventional linac that has constant strength quadrupoles. After some number of passes the focusing strength is insufficient to keep the beam from going unstable and being lost. In this project, the use of fast pulsed quadrupoles in the linac sections was considered for stronger focusing as a function of time to allow more successive passes of a muon beam in a recirculating linear accelerator. In one simulation, it was shown that the number of passes could be increased from 8 to 12 using pulsed magnet designs that have been developed and tested. This could reduce the cost of linac sections of a muon RLA by 8/12, where more improvement is still possible. The expense of a greater number of passes and corresponding number of return arcs was also addressed in this project by exploring the use of ramped or FFAG-style magnets in the return arcs. A better solution, invented in this project, is to use combined-function dipole-quadrupole magnets to simultaneously transport two beams of different energies through one magnet string to reduce costs of return arcs by almost a factor of

Jefferson Lab Data Acquisition Run Control System

International Nuclear Information System (INIS)

Vardan Gyurjyan; Carl Timmer; David Abbott; William Heyes; Edward Jastrzembski; David Lawrence; Elliott Wolin

2004-01-01

A general overview of the Jefferson Lab data acquisition run control system is presented. This run control system is designed to operate the configuration, control, and monitoring of all Jefferson Lab experiments. It controls data-taking activities by coordinating the operation of DAQ sub-systems, online software components and third-party software such as external slow control systems. The main, unique feature which sets this system apart from conventional systems is its incorporation of intelligent agent concepts. Intelligent agents are autonomous programs which interact with each other through certain protocols on a peer-to-peer level. In this case, the protocols and standards used come from the domain-independent Foundation for Intelligent Physical Agents (FIPA), and the implementation used is the Java Agent Development Framework (JADE). A lightweight, XML/RDF-based language was developed to standardize the description of the run control system for configuration purposes

78 FR 20314 - Jefferson Island Storage & Hub, L.L.C.; Notice of Filing

Science.gov (United States)

2013-04-04

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR13-44-000] Jefferson Island Storage & Hub, L.L.C.; Notice of Filing Take notice that on March 28, 2013, Jefferson Island Storage & Hub, L.L.C. filed to revise its Statement of Operating Conditions to among others, update...

New GPIB Control Software at Jefferson Lab

International Nuclear Information System (INIS)

Matthew Bickley; Pavel Chevtsov

2005-01-01

The control of GPIB devices at Jefferson Lab is based on the GPIB device/driver library. The library is a part of the device/driver development framework. It is activated with the use of the device configuration files that define all hardware components used in the control system to communicate with GPIB devices. As soon as the software is activated, it is ready to handle any device connected to these components and only needs to know the set of commands that the device can understand. The old GPIB control software at Jefferson Lab requires the definition of these commands in the form of a device control software module written in C for each device. Though such modules are relatively simple, they have to be created, successfully compiled, and supported for all control computer platforms. In the new version of GPIB control software all device communication commands are defined in device protocol (ASCII text) files. This makes the support of GPIB devices in the control system much easier

The New 2nd-Generation SRF RandD Facility at Jefferson Lab: TEDF

International Nuclear Information System (INIS)

Reece, Charles E.; Reilly, Anthony V.

2012-01-01

The US Department of Energy has funded a near-complete renovation of the SRF-based accelerator research and development facilities at Jefferson Lab. The project to accomplish this, the Technical and Engineering Development Facility (TEDF) Project has completed the first of two phases. An entirely new 3,100 m 2 purpose-built SRF technical work facility has been constructed and was occupied in summer of 2012. All SRF work processes with the exception of cryogenic testing have been relocated into the new building. All cavity fabrication, processing, thermal treatment, chemistry, cleaning, and assembly work is collected conveniently into a new LEED-certified building. An innovatively designed 800 m2 cleanroom/chemroom suite provides long-term flexibility for support of multiple RandD and construction projects as well as continued process evolution. The characteristics of this first 2nd-generation SRF facility are described

Transcription of Gail Jefferson, Boston University Conference on Ethnomethodology and Conversation Analysis, 9 June 1977

DEFF Research Database (Denmark)

Nevile, Maurice Richard

2015-01-01

This is a CLAN transcription of the film recording of a conference talk by Gail Jefferson in Boston in 1977. The film recording was generously made available by George Psathas, Emeritus Professor of Sociology at Boston University. Prof Doug Maynard (University of Wisconsin) arranged for the origi...... paralleling the talk’s content, under the heading ‘The Boston talk (as it never was)’ (p.2) - this would therefore seem to be adapted from Hopper’s transcription. So in my transcription I aim to give a clearer sense of the Boston talk as it actually was.......This is a CLAN transcription of the film recording of a conference talk by Gail Jefferson in Boston in 1977. The film recording was generously made available by George Psathas, Emeritus Professor of Sociology at Boston University. Prof Doug Maynard (University of Wisconsin) arranged...... for the original film recording to be digitised. Jefferson later developed elements of her 1977 talk into the paper ‘On the poetics of ordinary talk’ (Jefferson. G. 1996, in Text and Performance Quarterly, 16,1:1-61). An indication of the significance of the talk is given in that paper’s abstract, where Jefferson...

Ion Beam Facilities at the National Centre for Accelerator based Research using a 3 MV Pelletron Accelerator

Science.gov (United States)

Trivedi, T.; Patel, Shiv P.; Chandra, P.; Bajpai, P. K.

A 3.0 MV (Pelletron 9 SDH 4, NEC, USA) low energy ion accelerator has been recently installed as the National Centre for Accelerator based Research (NCAR) at the Department of Pure & Applied Physics, Guru Ghasidas Vishwavidyalaya, Bilaspur, India. The facility is aimed to carried out interdisciplinary researches using ion beams with high current TORVIS (for H, He ions) and SNICS (for heavy ions) ion sources. The facility includes two dedicated beam lines, one for ion beam analysis (IBA) and other for ion implantation/ irradiation corresponding to switching magnet at +20 and -10 degree, respectively. Ions with 60 kV energy are injected into the accelerator tank where after stripping positively charged ions are accelerated up to 29 MeV for Au. The installed ion beam analysis techniques include RBS, PIXE, ERDA and channelling.

Technical Design Report for the FACET-II Project at SLAC National Accelerator Laboratory

Energy Technology Data Exchange (ETDEWEB)

None, None

2016-08-26

Electrons can “surf” on waves of plasma – a hot gas of charged particles – gaining very high energies in very short distances. This approach, called plasma wakefield acceleration, has the potential to dramatically shrink the size and cost of particle accelerators. Research at the SLAC National Accelerator Laboratory has demonstrated that plasmas can provide 1,000 times the acceleration in a given distance compared with current technologies. Developing revolutionary and more efficient acceleration techniques that allow for an affordable high-energy collider has been the focus of FACET, a National User Facility at SLAC. FACET used part of SLAC’s two-mile-long linear accelerator to generate high-density beams of electrons and their antimatter counterparts, positrons. Research into plasma wakefield acceleration was the primary motivation for constructing FACET. In April 2016, FACET operations came to an end to make way for the second phase of SLAC’s x-ray laser, the LCLS-II, which will use part of the tunnel occupied by FACET. FACET-II is a new test facility to provide the unique capability to develop advanced acceleration and coherent radiation techniques with high-energy electron and positron beams. FACET-II represents a major upgrade over current FACET capabilities and the breadth of the potential research program makes it truly unique.

A Proposed Incentive System for Jefferson County Teachers.

Science.gov (United States)

Schlechty, Phillip C.; Ingwerson, Donald W.

1987-01-01

Outlines a teacher incentive plan developed for the Jefferson County (Kentucky) Public Schools and scheduled for pilot testing during the 1987-88 school year. The program is modeled after airline frequent flyer programs and is designed to encourage cooperative action and individual incentive among teachers. (MD)

Compensation Techniques in Accelerator Physics

Energy Technology Data Exchange (ETDEWEB)

Sayed, Hisham Kamal [Old Dominion Univ., Norfolk, VA (United States)

2011-05-01

Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along with applying state of the art techniques in beam dynamics will be used in this dissertation to study and solve accelerator physics problems. Two problems involving compensation are studied in the context of the MEIC (Medium Energy Electron Ion Collider) project at Jefferson Laboratory. Several chromaticity (the energy dependence of the particle tune) compensation methods are evaluated numerically and deployed in a figure eight ring designed for the electrons in the collider. Furthermore, transverse coupling optics have been developed to compensate the coupling introduced by the spin rotators in the MEIC electron ring design.

Hall A

Data.gov (United States)

Federal Laboratory Consortium — The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electroand photo-induced reactions at very high luminosity...

Final Report - Development of a Multi-Spoke Superconducting Cavity for Nuclear Physics, Light Sources, and Driven Systems Applications (ODU Contribution)

Energy Technology Data Exchange (ETDEWEB)

Delayen, Jean [Old Dominion Univ., Norfolk, VA (United States)

2014-11-14

This report summarizes the work done by Old Dominion University, in collaboration with the Thomas Jefferson National Accelerator Facility toward the development of high-velocity superconducting spoke cavities.

Classical Ethics, Jefferson's Christian Epicureanism, and American Morality.

Science.gov (United States)

Lawler, Peter Augustine

1991-01-01

Outlines Thomas Jefferson's views of classic philosophical writers and various interpretations of their views on morality and epicureanism. Explains why teaching ancient and medieval political philosophy is necessary as an ethical supplement to U.S. political thought. States liberal democracy depends on the tension between reason and revelation.…

Status of the LCLS-II Accelerating Cavity Production

Energy Technology Data Exchange (ETDEWEB)

Daly, Ed [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Marhauser, Frank [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Fitzpatrick, Jarrod A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Palczewski, Ari D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Preble, Joe [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Wilson, Katherine M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Grimm, C. J. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Burrill, Andrew B. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Gonnella, Daniel [SLAC National Accelerator Lab., Menlo Park, CA (United States)

2017-05-01

Cavity serial production for the LCLS-II 4 GeV CM SRF linac has started. A quantity of 266 accelerating cavities has been ordered from two industrial vendors. Jefferson Laboratory leads the cavity procurement activities for the project and has successfully transferred the Nitrogen-Doping process to the industrial partners in the initial phase, which is now being applied for the production cavities. We report on the results from vendor qualification and the status of the cavity production for LCLS-II.

Brookhaven National Laboratory's Accelerator Test Facility: research highlights and plans

Science.gov (United States)

Pogorelsky, I. V.; Ben-Zvi, I.

2014-08-01

The Accelerator Test Facility (ATF) at Brookhaven National Laboratory has served as a user facility for accelerator science for over a quarter of a century. In fulfilling this mission, the ATF offers the unique combination of a high-brightness 80 MeV electron beam that is synchronized to a 1 TW picosecond CO2 laser. We unveil herein our plan to considerably expand the ATF's floor space with an upgrade of the electron beam's energy to 300 MeV and the CO2 laser's peak power to 100 TW. This upgrade will propel the ATF even further to the forefront of research on advanced accelerators and radiation sources, supporting the most innovative ideas in this field. We discuss emerging opportunities for scientific breakthroughs, including the following: plasma wakefield acceleration studies in research directions already active at the ATF; laser wakefield acceleration (LWFA), where the longer laser wavelengths are expected to engender a proportional increase in the beam's charge while our linac will assure, for the first time, the opportunity to undertake detailed studies of seeding and staging of the LWFA; proton acceleration to the 100-200 MeV level, which is essential for medical applications; and others.

Continuous wave superconducting radio frequency electron linac for nuclear physics research

International Nuclear Information System (INIS)

Reece, Charles E.

2016-01-01

CEBAF, the Continuous Electron Beam Accelerator Facility, has been actively serving the nuclear physics research community as a unique forefront international resource since 1995. This cw electron linear accelerator (linac) at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility (Jefferson Lab) has continued to evolve as a precision tool for discerning the structure and dynamics within nuclei. Superconducting rf (SRF) technology has been the essential foundation for CEBAF, first as a 4 GeV machine, then 6 GeV, and currently capable of 12 GeV. Lastly, we review the development, implementation, and performance of SRF systems for CEBAF from its early beginnings to the commissioning of the 12 GeV era.

Evaluating RAID in the real world

International Nuclear Information System (INIS)

Ian Bird; Rita Chambers; Mark Davis; Andy Kowalski; Bob Lukens; Sandy Philpott; Roy Whitney

1998-01-01

High energy nuclear physics experiments at Thomas Jefferson National Accelerator Facility (''Jefferson Lab'') will have a data collection rate of 10 MB/second, generating 1 Terabyte (TB) of raw data per day of accelerator running, and a similar amount after processing. The requirement for on-line disk storage for raw and reduced data sets will exceed 1 TB during 1998. This paper discusses the on-line storage strategy that provides both high performance as well as high capacity, and focuses on the in-house evaluation of RAID (Redundant Arrays of Independent Disks) systems to fulfill the needs of both data acquisition and analysis

Utilization of Integrated Process Control, Data Capture, and Data Analysis in Construction of Accelerator Systems

International Nuclear Information System (INIS)

Bonnie Madre; Charles Reece; Joseph Ozelis; Valerie Bookwalter

2003-01-01

Jefferson Lab has developed a web-based system that integrates commercial database, data analysis, document archiving and retrieval, and user interface software, into a coherent knowledge management product (Pansophy). This product provides important tools for the successful pursuit of major projects such as accelerator system development and construction, by offering elements of process and procedure control, data capture and review, and data mining and analysis. After a period of initial development, Pansophy is now being used in Jefferson Lab's SNS superconducting linac construction effort, as a means for structuring and implementing the QA program, for process control and tracking, and for cryomodule test data capture and presentation/analysis. Development of Pansophy is continuing, in particular data queries and analysis functions that are the cornerstone of its utility

SNS Cryomodule Performance

International Nuclear Information System (INIS)

Isidoro Campisi; Edward Daly; G. Davis; Jean Delayen; Michael Drury; Christiana Grenoble; John Hogan; Lawrence King; Peter Kneisel; John Mammosser; Thomas Powers; Joseph Preble; Mircia Stirbet; Haipeng Wang; Tim Whitlatch; Mark Wiseman

2003-01-01

Thomas Jefferson National Accelerating Facility, Jefferson Lab, is producing 24 Superconducting Radio FR-equency (SRF) cryomodules for the Spallation Neutron Source (SNS) cold linac. This includes one medium beta (0.61) prototype, 11 medium beta production, and 12 high beta (0.81) production cryomodules. After testing [ ], the medium beta prototype cryomodule was shipped to Oak Ridge National Laboratory (ORNL) and acceptance check out has been completed. All production orders for cavities and cryomodule components are being received at this time and the medium beta cryomodule production run has started. Each of the medium beta cryomodules is scheduled to undergo complete operational performance testing at Jefferson Laboratory before shipment to ORNL. The performance results of cryomodules to date will be discussed

Preliminary Conceptual Design Report for the FACET-II Project at SLAC National Accelerator Laboratory

Energy Technology Data Exchange (ETDEWEB)

Hogan, Mark [SLAC National Accelerator Lab., Menlo Park, CA (United States)

2016-04-22

Plasma wakefield acceleration has the potential to dramatically shrink the size and cost of particle accelerators. Research at the SLAC National Accelerator Laboratory has demonstrated that plasmas can provide 1,000 times the acceleration in a given distance compared with current technologies. Developing revolutionary and more efficient acceleration techniques that allow for an affordable high-energy collider is the focus of FACET, a National User Facility at SLAC. The existing FACET National User Facility uses part of SLAC’s two-mile-long linear accelerator to generate high-density beams of electrons and positrons. FACET-II is a new test facility to develop advanced acceleration and coherent radiation techniques with high-energy electron and positron beams. It is the only facility in the world with high energy positron beams. FACET-II provides a major upgrade over current FACET capabilities and the breadth of the potential research program makes it truly unique. It will synergistically pursue accelerator science that is vital to the future of both advanced acceleration techniques for High Energy Physics, ultra-high brightness beams for Basic Energy Science, and novel radiation sources for a wide variety of applications. The design parameters for FACET-II are set by the requirements of the plasma wakefield experimental program. To drive the plasma wakefield requires a high peak current, in excess of 10kA. To reach this peak current, the electron and positron design bunch size is 10μ by 10μ transversely with a bunch length of 10μ. This is more than 200 times better than what has been achieved at the existing FACET. The beam energy is 10 GeV, set by the Linac length available and the repetition rate is up to 30 Hz. The FACET-II project is scheduled to be constructed in three major stages. Components of the project discussed in detail include the following: electron injector, bunch compressors and linac, the positron system, the Sector 20 sailboat and W chicanes

Future Scientific Opportunities At Jefferson Lab

International Nuclear Information System (INIS)

Thomas, Anthony

2007-01-01

Nuclear physics requires at least one major facility world-wide which is capable of fully exploiting the properties of the electro-weak force to investigate precisely the structure of strongly interacting systems. At its current maximum energy of 6 GeV Jefferson Lab has provided a wealth of important information on the structure of nucleons and nuclei. However, the plans to double the energy over the next seven years promise to open new frontiers in nuclear and particle physics. We briefly describe the plans for the 12 GeV Upgrade and the associated physics opportunities.

ADVANTAGES OF THE PROGRAM-BASED LOGBOOK SUBMISSION GUI AT JEFFERSON LAB

Energy Technology Data Exchange (ETDEWEB)

T. McGuckin

2006-10-24

DTlite is a Tcl/Tk script that is used as the primary interface for making entries into Jefferson Lab's electronic logbooks. DTlite was originally written and implemented by a user to simplify submission of entries into Jefferson Lab?s electronic logbook, but has subsequently been maintained and developed by the controls software group. The use of a separate, script-based tool for logbook submissions (as opposed to a web-based submission tool bundled with the logbook database/interface) provides many advantages to the users, as well as creating many challenges to the programmers and maintainers of the electronic logbook system. The paper describes the advantages and challenges of this design model and how they have affected the development lifecycle of the electronic logbook system.

High-intensity positron microprobe at the Thomas Jefferson National Accelerator Facility

International Nuclear Information System (INIS)

Golge, S.; Vlahovic, B.; Wojtsekhowski, B.

2014-01-01

We present a conceptual design for a novel continuous wave electron-linac based high-intensity high-brightness slow-positron production source with a projected intensity on the order of 10 10  e + /s. Reaching this intensity in our design relies on the transport of positrons (T + below 600 keV) from the electron-positron pair production converter target to a low-radiation and low-temperature area for moderation in a high-efficiency cryogenic rare gas moderator, solid Ne. This design progressed through Monte Carlo optimizations of: electron/positron beam energies and converter target thickness, transport of the e + beam from the converter to the moderator, extraction of the e + beam from the magnetic channel, a synchronized raster system, and moderator efficiency calculations. For the extraction of e + from the magnetic channel, a magnetic field terminator plug prototype has been built and experimental results on the effectiveness of the prototype are presented. The dissipation of the heat away from the converter target and radiation protection measures are also discussed.

High-intensity positron microprobe at the Thomas Jefferson National Accelerator Facility

Energy Technology Data Exchange (ETDEWEB)

Golge, S., E-mail: serkan.golge@nasa.gov; Vlahovic, B. [North Carolina Central University, Durham, North Carolina 27707 (United States); Wojtsekhowski, B. [Jefferson Laboratory, 12000 Jefferson Ave., Newport News, Virginia 23606 (United States)

2014-06-21

We present a conceptual design for a novel continuous wave electron-linac based high-intensity high-brightness slow-positron production source with a projected intensity on the order of 10{sup 10 }e{sup +}/s. Reaching this intensity in our design relies on the transport of positrons (T{sub +} below 600 keV) from the electron-positron pair production converter target to a low-radiation and low-temperature area for moderation in a high-efficiency cryogenic rare gas moderator, solid Ne. This design progressed through Monte Carlo optimizations of: electron/positron beam energies and converter target thickness, transport of the e{sup +} beam from the converter to the moderator, extraction of the e{sup +} beam from the magnetic channel, a synchronized raster system, and moderator efficiency calculations. For the extraction of e{sup +} from the magnetic channel, a magnetic field terminator plug prototype has been built and experimental results on the effectiveness of the prototype are presented. The dissipation of the heat away from the converter target and radiation protection measures are also discussed.

Continuous wave superconducting radio frequency electron linac for nuclear physics research

Directory of Open Access Journals (Sweden)

Charles E. Reece

2016-12-01

Full Text Available CEBAF, the Continuous Electron Beam Accelerator Facility, has been actively serving the nuclear physics research community as a unique forefront international resource since 1995. This cw electron linear accelerator (linac at the U.S. Department of Energy’s Thomas Jefferson National Accelerator Facility (Jefferson Lab has continued to evolve as a precision tool for discerning the structure and dynamics within nuclei. Superconducting rf (SRF technology has been the essential foundation for CEBAF, first as a 4 GeV machine, then 6 GeV, and currently capable of 12 GeV. We review the development, implementation, and performance of SRF systems for CEBAF from its early beginnings to the commissioning of the 12 GeV era.

R&D PROPOSAL FOR THE NATIONAL MUON ACCELERATOR PROGRAM

Energy Technology Data Exchange (ETDEWEB)

Muon Accelerator Program; Zisman, Michael S.; Geer, Stephen

2010-02-24

This document contains a description of a multi-year national R&D program aimed at completing a Design Feasibility Study (DFS) for a Muon Collider and, with international participation, a Reference Design Report (RDR) for a muon-based Neutrino Factory. It also includes the supporting component development and experimental efforts that will inform the design studies and permit an initial down-selection of candidate technologies for the ionization cooling and acceleration systems. We intend to carry out this plan with participants from the host national laboratory (Fermilab), those from collaborating U.S. national laboratories (ANL, BNL, Jlab, LBNL, and SNAL), and those from a number of other U.S. laboratories, universities, and SBIR companies. The R&D program that we propose will provide the HEP community with detailed information on future facilities based on intense beams of muons--the Muon Collider and the Neutrino Factory. We believe that these facilities offer the promise of extraordinary physics capabilities. The Muon Collider presents a powerful option to explore the energy frontier and the Neutrino Factory gives the opportunity to perform the most sensitive neutrino oscillation experiments possible, while also opening expanded avenues for the study of new physics in the neutrino sector. The synergy between the two facilities presents the opportunity for an extremely broad physics program and a unique pathway in accelerator facilities. Our work will give clear answers to the questions of expected capabilities and performance of these muon-based facilities, and will provide defensible ranges for their cost. This information, together with the physics insights gained from the next-generation neutrino and LHC experiments, will allow the HEP community to make well-informed decisions regarding the optimal choice of new facilities. We believe that this work is a critical part of any broad strategic program in accelerator R&D and, as the P5 panel has recently

A psychometric appraisal of the Jefferson Scale of Empathy using law students

Directory of Open Access Journals (Sweden)

Williams B

2016-07-01

Full Text Available Brett Williams,1 Adiva Sifris,2 Marty Lynch1 1Department of Community Emergency Health and Paramedic Practice, Faculty of Medicine, Nursing and Health Sciences, 2Faculty of Law, Monash University, Frankston, VIC, Australia Background: A growing body of literature indicates that empathic behaviors are positively linked, in several ways, with the professional performance and mental well-being of lawyers and law students. It is therefore important to assess empathy levels among law students using psychometrically sound tools that are suitable for this cohort.Participants and methods: The 20-item Jefferson Scale of Empathy – Health Profession Students Version was adapted for a law context (eg, the word “health care” became “legal”, and the new Jefferson Scale of Empathy – Law Students (JSE-L-S version was completed by 275 students at Monash University, Melbourne, Australia. Data were subjected to principal component analysis.Results: Four factors emerged from the principal component analysis (“understanding the client’s perspective”, “responding to clients’ experiences and emotions”, “responding to clients’ cues and behaviors”, and “standing in clients’ shoes”, which accounted for 46.7% of the total variance. The reliability of the factors varied, but the overall 18-item JSE-L-S yielded a Cronbach’s alpha coefficient of 0.80. Several patterns among the item loadings were similar to those reported in studies using other versions of the Jefferson Scale of Empathy.Conclusion: The JSE-L-S appears to be a reliable measure of empathy among undergraduate law students, which could help provide insights into law student welfare and future performance as legal practitioners. Additional evaluation of the JSE-L-S is required to disambiguate some of the minor findings explored. Adjustments may improve the psychometric properties. Keywords: empathy, law, student, Jefferson, sympathy

Radioecological studies at the National Accelerator Centre based on the determination of 129I by accelerator mass spectrometry (AMS)

International Nuclear Information System (INIS)

Lopez-Gutierrez, J. M.; Gomez-Guzman, J. M.; Chamizo, E.; Santos, F. J.; Garcia-Leon, M.; Garcia-Tenorio, R.

2013-01-01

Since 2006 a compact system of mass spectrometry with Accelerator (AMS) is installed at the National Center of Accelerators, Seville. After an initial set-up and study have been opening many lines of research in fields such as archeology, geology, paleontology, oceanography, oceanography, internal dosimetry and characterization of radioactive waste, among others. In particular, based on the measurement of 1 29I have made contributions to the field of radioecology and radiation protection. In this work they are summarized and presented some of these investigations. (Author)

Experimental Studies of Quark-Gluon Structure of Nucleons and Nuclei

International Nuclear Information System (INIS)

Kyle, Gary

2004-01-01

The NMSU group has a lengthy history in the study of the nucleon structure and in particular its spin structure in terms of its fundamental constituents. This line of research is continuing in our current involvement in experiments at Brookhaven National Lab and the Thomas Jefferson National Accelerator Facility

Performance report of the U.S. Department of Energy's Jefferson Lab

International Nuclear Information System (INIS)

Jefferson Lab

1999-01-01

Jefferson Lab, the newest of the US Department of Energy's 16 national laboratories, has been functioning effectively since its inception in 1984, first during construction and later during operations. As shown in this report, JLab aligns itself directly with DOE's strategic planning, both in terms of laboratory visions and plans and in terms of actual laboratory performance. Most importantly, JLab contributes significantly to DOE's Science and Technology mission in the area of nuclear physics, under the Office of Science. The laboratory practices continuous improvement and has made a number of important effectiveness and efficiency enhancements in recent years. Laboratory performance has been demonstrated by completion of the construction phase on cost and schedule, by exceeding technical specifications when coming on-line for physics research, and then - during operations in the mid- and late- 1990's - by the application of the performance measures in the laboratory's performance-based contract with DOE

Establishing KEK in Japan and Fermilab in the US: internationalism, nationalism and high energy accelerators

Energy Technology Data Exchange (ETDEWEB)

Hoddeson, L. (Fermi National Accelerator Lab., Batavia, IL (USA); Illinois Univ., Urbana (USA). Dept. of Physics)

1983-02-01

Comparison of the prehistories of the Fermi National Accelerator Laboratory (Fermilab) in the US, and Ko-bar Enerugii Butsurigaku Kenkyusho (KEK) in Japan, reveals the working of both internationalism and nationalism in high energy physics. International communication and competition helped to create a number of structural parallels from the 1930s to the 1960s; for example, in the postwar period both countries formed their first inter-university government-supported accelerator laboratories; at the turn of the 1960s nuclear physicists in both countries debated about the choice of design for their next higher energy accelerator; and both chose proton synchrotron designs traceable to a common conceptual root. Although Fermilab and KEK progressed through analogous stages in 1960-65, national circumstances caused these developments to diverge in the late 1960s, resulting in a sizeable cut in scale and costly delays in the establishment of KEK.

Establishing KEK in Japan and Fermilab in the US: internationalism, nationalism and high energy accelerators

International Nuclear Information System (INIS)

Hoddeson, L.; Illinois Univ., Urbana

1983-01-01

Comparison of the prehistories of the Fermi National Accelerator Laboratory (Fermilab) in the US, and Ko-bar Enerugii Butsurigaku Kenkyusho (KEK) in Japan, reveals the working of both internationalism and nationalism in high energy physics. International communication and competition helped to create a number of structural parallels from the 1930s to the 1960s; for example, in the postwar period both countries formed their first inter-university government-supported accelerator laboratories; at the turn of the 1960s nuclear physicists in both countries debated about the choice of design for their next higher energy accelerator; and both chose proton synchrotron designs traceable to a common conceptual root. Although Fermilab and KEK progressed through analogous stages in 1960-65, national circumstances caused these developments to diverge in the late 1960s, resulting in a sizeable cut in scale and costly delays in the establishment of KEK. (author)

Rapid ascent: Rocky Mountain National Park in the Great Acceleration, 1945-present

Science.gov (United States)

Boxell, Mark

After the Second World War's conclusion, Rocky Mountain National Park (RMNP) experienced a massive rise in visitation. Mobilized by an affluent economy and a growing, auto-centric infrastructure, Americans rushed to RMNP in droves, setting off new concerns over the need for infrastructure improvements in the park. National parks across the country experienced similar explosions in visitation, inspiring utilities- and road-building campaigns throughout the park units administered by the National Park Service. The quasi-urbanization of parks like RMNP implicated the United States' public lands in a process of global change, whereby wartime technologies, cheap fossil fuels, and a culture of techno-optimism--epitomized by the Mission 66 development program--helped foster a "Great Acceleration" of human alterations of Earth's natural systems. This transformation culminated in worldwide turns toward mass-urbanization, industrial agriculture, and globalized markets. The Great Acceleration, part of the Anthropocene--a new geologic epoch we have likely entered, which proposes that humans have become a force of geologic change--is used as a conceptual tool for understanding the connections between local and global changes which shaped the park after World War II. The Great Acceleration and its array of novel technologies and hydrocarbon-powered infrastructures produced specific cultures of tourism and management techniques within RMNP. After World War II, the park increasingly became the product and distillation of a fossil fuel-dependent society.

Determination of the Optimal Operating Parameters for Jefferson Laboratory's Cryogenic Cold Compressor Systems

Energy Technology Data Exchange (ETDEWEB)

Wilson, Jr., Joe D. [Christopher Newport Univ., Newport News, VA (United States)

2003-01-01

The technology of Jefferson Laboratory's (JLab) Continuous Electron Beam Accelerator Facility (CEBAF) and Free Electron Laser (FEL) requires cooling from one of the world's largest 2K helium refrigerators known as the Central Helium Liquefier (CHL). The key characteristic of CHL is the ability to maintain a constant low vapor pressure over the large liquid helium inventory using a series of five cold compressors. The cold compressor system operates with a constrained discharge pressure over a range of suction pressures and mass flows to meet the operational requirements of CEBAF and FEL. The research topic is the prediction of the most thermodynamically efficient conditions for the system over its operating range of mass flows and vapor pressures with minimum disruption to JLab operations. The research goal is to find the operating points for each cold compressor for optimizing the overall system at any given flow and vapor pressure.

Fast feedback system for energy and beam stabilization

International Nuclear Information System (INIS)

R. Dickson; V. Lebedev

1999-01-01

The electron beams being delivered to targets of the Continuous Electron Beam Accelerator Facility (CEBAF) at Thomas Jefferson National Accelerator Facility (Jefferson Lab) are plagued with undesirable positional and energy fluctuations. These fluctuations primarily occur at harmonics of the power line frequency (60, 120, 180, etc. hertz), and their cause is rooted in electromagnetic fields generated by accelerator electronic equipment. It is possible to largely nullify these deviations by applying real time corrections to electromagnets and RF verniers along the beam line. This concept has been successfully applied at Jefferson Lab by extensively modifying the existing Beam Position Monitor (BPM) system with the integration of an algorithm that computes correction signals targeted at the power line harmonics. Many of the modifications required were due to the existing CEBAF BPM system not having the data acquisition bandwidth needed for this type of feedback system. This paper will describe the techniques required to transform the CEBAF standard BPM system into a high speed practical fast feedback system that coexists with the large scale control system--the Experimental Physics and Industrial Control System (EPICS)--that runs the CEBAF accelerator in daily operation

Precision Electron Beam Polarimetry in Hall C at Jefferson Lab

Science.gov (United States)

Gaskell, David

2013-10-01

The electron beam polarization in experimental Hall C at Jefferson Lab is measured using two devices. The Hall-C/Basel Møller polarimeter measures the beam polarization via electron-electron scattering and utilizes a novel target system in which a pure iron foil is driven to magnetic saturation (out of plane) using a superconducting solenoid. A Compton polarimeter measures the polarization via electron-photon scattering, where the photons are provided by a high-power, CW laser coupled to a low gain Fabry-Perot cavity. In this case, both the Compton-scattered electrons and backscattered photons provide measurements of the beam polarization. Results from both polarimeters, acquired during the Q-Weak experiment in Hall C, will be presented. In particular, the results of a test in which the Møller and Compton polarimeters made interleaving measurements at identical beam currents will be shown. In addition, plans for operation of both devices after completion of the Jefferson Lab 12 GeV Upgrade will also be discussed.

78 FR 36545 - Notice of Ability To Pay-Cash-out Settlement Agreement for the Jefferson City Residential Yards...

Science.gov (United States)

2013-06-18

... ENVIRONMENTAL PROTECTION AGENCY [FRL-9824-4] Notice of Ability To Pay--Cash-out Settlement... payment of certain response costs incurred at the Jefferson City Residential Yards Site in Jefferson City... portion of the past costs expended at the Site. Payment shall be made in 35 installments of $2,500 per...

Nuclear physics accelerator facilities

International Nuclear Information System (INIS)

1988-12-01

This paper describes many of the nuclear physics heavy-ion accelerator facilities in the US and the research programs being conducted. The accelerators described are: Argonne National Laboratory--ATLAS; Brookhaven National Laboratory--Tandem/AGS Heavy Ion Facility; Brookhaven National Laboratory--Relativistic Heavy Ion Collider (RHIC) (Proposed); Continuous Electron Beam Accelerator Facility; Lawrence Berkeley Laboratory--Bevalac; Lawrence Berkeley Laboratory--88-Inch Cyclotron; Los Alamos National Laboratory--Clinton P. Anderson Meson Physics Facility (LAMPF); Massachusetts Institute of Technology--Bates Linear Accelerator Center; Oak Ridge National Laboratory--Holifield Heavy Ion Research Facility; Oak Ridge National Laboratory--Oak Ridge Electron Linear Accelerator; Stanford Linear Accelerator Center--Nuclear Physics Injector; Texas AandM University--Texas AandM Cyclotron; Triangle Universities Nuclear Laboratory (TUNL); University of Washington--Tandem/Superconducting Booster; and Yale University--Tandem Van de Graaff

Recirculating Beam Breakup Study for the 12 GeV Upgrade at Jefferson Lab

International Nuclear Information System (INIS)

Shin, Ilkyoung; Satogata, Todd; Ahmed, Shahid; Bogacz, Slawomir; Stirbet, Mircea; Wang, Haipeng; Wang, Yan; Yunn, Byung; Bodenstein, Ryan

2012-01-01

Two new high gradient C100 cryomodules with a total of 16 new cavities were installed at the end of the CEBAF south linac during the 2011 summer shutdown as part of the 12-GeV upgrade project at Jefferson Lab. We surveyed the higher order modes (HOMs) of these cavities in the Jefferson Lab cryomodule test facility and CEBAF tunnel. We then studied recirculating beam breakup (BBU) in November 2011 to evaluate CEBAF low energy performance, measure transport optics, and evaluate BBU thresholds due to these HOMs. This paper discusses the experiment setup, cavity measurements, machine setup, optics measurements, and lower bounds on BBU thresholds by new cryomodules.

Recirculating Beam Breakup Study for the 12 GeV Upgrade at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Ilkyoung Shin, Todd Satogata, Shahid Ahmed, Slawomir Bogacz, Mircea Stirbet, Haipeng Wang, Yan Wang, Byung Yunn, Ryan Bodenstein

2012-07-01

Two new high gradient C100 cryomodules with a total of 16 new cavities were installed at the end of the CEBAF south linac during the 2011 summer shutdown as part of the 12-GeV upgrade project at Jefferson Lab. We surveyed the higher order modes (HOMs) of these cavities in the Jefferson Lab cryomodule test facility and CEBAF tunnel. We then studied recirculating beam breakup (BBU) in November 2011 to evaluate CEBAF low energy performance, measure transport optics, and evaluate BBU thresholds due to these HOMs. This paper discusses the experiment setup, cavity measurements, machine setup, optics measurements, and lower bounds on BBU thresholds by new cryomodules.

R&D PROPOSAL FOR THE NATIONAL MUON ACCELERATOR PROGRAM

OpenAIRE

Zisman, Michael S.

2011-01-01

This document contains a description of a multi-year national R&D program aimed at completing a Design Feasibility Study (DFS) for a Muon Collider and, with international participation, a Reference Design Report (RDR) for a muon-based Neutrino Factory. It also includes the supporting component development and experimental efforts that will inform the design studies and permit an initial down-selection of candidate technologies for the ionization cooling and acceleration systems. We intend to ...

76 FR 57748 - National Cancer Institute Notice of Closed Meetings

Science.gov (United States)

2011-09-16

... Logistics Branch, Division of Extramural Activities, National Cancer Institute, 6116 Executive Boulevard... Crystal City, 2799 Jefferson Davis Highway, Arlington, VA 22202. Contact Person: Sergei Radaev, PhD..., Scientific Review Officer, Special Review Logistics Branch, Division of Extramural Activities, National...

Polarized Source Performance and Developments at Jefferson Lab

International Nuclear Information System (INIS)

Matt Poelker; P. Adderley; J. Clark; A. Day; Joseph Grames; J. Hansknecht; P. Hartmann; R. Kazimi; P. Rutt; Charles Sinclair; M. Steigerwald

2000-01-01

The polarized photoinjector at Jefferson Lab continues to provide high average current, high polarization, high quality beam to nuclear physics Users in as many as three endstations simultaneously. Long lifetime operation has been obtained from two identical polarized guns. A new high power mode locked Ti-sapphire laser has been constructed to enhance the effective operating lifetime of the photoinjector. Efforts to enhance beam polarization and reduced helicity correlated beam systematic effects are underway

Innovative applications of genetic algorithms to problems in accelerator physics

Directory of Open Access Journals (Sweden)

Alicia Hofler

2013-01-01

Full Text Available The genetic algorithm (GA is a powerful technique that implements the principles nature uses in biological evolution to optimize a multidimensional nonlinear problem. The GA works especially well for problems with a large number of local extrema, where traditional methods (such as conjugate gradient, steepest descent, and others fail or, at best, underperform. The field of accelerator physics, among others, abounds with problems which lend themselves to optimization via GAs. In this paper, we report on the successful application of GAs in several problems related to the existing Continuous Electron Beam Accelerator Facility nuclear physics machine, the proposed Medium-energy Electron-Ion Collider at Jefferson Lab, and a radio frequency gun-based injector. These encouraging results are a step forward in optimizing accelerator design and provide an impetus for application of GAs to other problems in the field. To that end, we discuss the details of the GAs used, include a newly devised enhancement which leads to improved convergence to the optimum, and make recommendations for future GA developments and accelerator applications.

Empirically Determined Response Matrices for On-Line Orbit and Energy Correction at Jefferson Lab

International Nuclear Information System (INIS)

Leigh Harwood; Alicia Hofler; Michele Joyce; Valeri Lebedev; David Bryan

2001-01-01

Jefferson Lab uses feedback loops (less than 1 hertz update rate) to correct drifts in CEBAF's electron beam orbit and energy. Previous incarnations of these loops used response matrices that were computed by a numerical model of the machine. Jefferson Lab is transitioning this feedback system to use empirically determined response matrices whereby the software introduces small orbit or energy deviations using the loop's actuators and measures the system response with the loop's sensors. This method is in routine use for orbit correction. This paper will describe the orbit correction system and future plans to extend this method to energy correction

NRDA-processed CTD data from NOAA Ship THOMAS JEFFERSON in the Gulf of Mexico, Cruise 2 Leg 1, collected from 2010-06-03 to 2010-06-10, associated with the Deepwater Horizon Oil Spill event (NCEI Accession 0128380)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Conductivity Temperature and Depth (CTD) measurements were collected aboard NOAA Ship Thomas Jefferson to determine physical oceanographic parameters of the water...

NRDA-processed CTD data from NOAA Ship THOMAS JEFFERSON in the Gulf of Mexico, Cruise 3 Leg 1, collected from 2010-06-06 to 2010-06-26, associated with the Deepwater Horizon Oil Spill event (NCEI Accession 0128381)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Conductivity Temperature and Depth (CTD) measurements were collected aboard NOAA Ship Thomas Jefferson to determine physical oceanographic parameters of the water...

Review of ingot niobium as a material for superconducting radiofrequency accelerating cavities

Energy Technology Data Exchange (ETDEWEB)

Kneisel, P., E-mail: kneisel@jlab.org [Jefferson Lab, Newport News, VA 23606 (United States); Ciovati, G.; Dhakal, P. [Jefferson Lab, Newport News, VA 23606 (United States); Saito, K. [Michigan State University, East Lansing, MI 48824 (United States); Singer, W.; Singer, X. [DESY, Notkestrasse 85, D-22607 Hamburg (Germany); Myneni, G.R., E-mail: rao@jlab.org [Jefferson Lab, Newport News, VA 23606 (United States)

2015-02-21

As a result of collaboration between Jefferson Lab and niobium manufacturer Companhia Brasileira de Metalurgia e Mineração (CBMM), ingot niobium was explored as a possible material for superconducting radiofrequency (SRF) cavity fabrication. The first single cell cavity from large-grain high purity niobium was fabricated and successfully tested at Jefferson Lab in 2004. This work triggered research activities in other SRF laboratories around the world. Large-grain (LG) niobium became not only an interesting alternative material for cavity builders, but also material scientists and surface scientists were eager to participate in the development of this technology. Many single cell cavities made from material of different suppliers have been tested successfully and several multi-cell cavities have shown performances comparable to the best cavities made from standard fine-grain niobium. Several 9-cell cavities fabricated by Research Instruments and tested at DESY exceeded the best performing fine grain cavities with a record accelerating gradient of E{sub acc}=45.6 MV/m. The quality factor of those cavities was also higher than that of fine-grain (FG) cavities processed with the same methods. Such performance levels push the state-of-the art of SRF technology and are of great interest for future accelerators. This contribution reviews the development of ingot niobium technology and highlights some of the differences compared to standard FG material and opportunities for further developments.

Economic-environmental modeling of point source pollution in Jefferson County, Alabama, USA.

Science.gov (United States)

Kebede, Ellene; Schreiner, Dean F; Huluka, Gobena

2002-05-01

This paper uses an integrated economic-environmental model to assess the point source pollution from major industries in Jefferson County, Northern Alabama. Industrial expansion generates employment, income, and tax revenue for the public sector; however, it is also often associated with the discharge of chemical pollutants. Jefferson County is one of the largest industrial counties in Alabama that experienced smog warnings and ambient ozone concentration, 1996-1999. Past studies of chemical discharge from industries have used models to assess the pollution impact of individual plants. This study, however, uses an extended Input-Output (I-O) economic model with pollution emission coefficients to assess direct and indirect pollutant emission for several major industries in Jefferson County. The major findings of the study are: (a) the principal emission by the selected industries are volatile organic compounds (VOC) and these contribute to the ambient ozone concentration; (b) the direct and indirect emissions are significantly higher than the direct emission by some industries, indicating that an isolated analysis will underestimate the emission by an industry; (c) while low emission coefficient industries may suggest industry choice they may also emit the most hazardous chemicals. This study is limited by the assumptions made, and the data availability, however it provides a useful analytical tool for direct and cumulative emission estimation and generates insights on the complexity in choice of industries.

Evaluation of a server-client architecture for accelerator modeling and simulation

International Nuclear Information System (INIS)

Bowling, B.A.; Akers, W.; Shoaee, H.; Watson, W.; Zeijts, J. van; Witherspoon, S.

1997-01-01

Traditional approaches to computational modeling and simulation often utilize a batch method for code execution using file-formatted input/output. This method of code implementation was generally chosen for several factors, including CPU throughput and availability, complexity of the required modeling problem, and presentation of computation results. With the advent of faster computer hardware and the advances in networking and software techniques, other program architectures for accelerator modeling have recently been employed. Jefferson Laboratory has implemented a client/server solution for accelerator beam transport modeling utilizing a query-based I/O. The goal of this code is to provide modeling information for control system applications and to serve as a computation engine for general modeling tasks, such as machine studies. This paper performs a comparison between the batch execution and server/client architectures, focusing on design and implementation issues, performance, and general utility towards accelerator modeling demands

Unknown oceanographic data collected aboard NOAA Ship THOMAS JEFFERSON in the Gulf of Mexico from 2010-05-23 to 2010-05-28 in response to the Deepwater Horizon Oil Spill event (NODC Accession 0084596)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Unknown oceanographic data were collected aboard NOAA Ship THOMAS JEFFERSON in the Gulf of Mexico from 2010-05-23 to 2010-05-28 in response to the Deepwater Horizon...

Assessing environmental risk of the retired filter bed area, Battelle West Jefferson

International Nuclear Information System (INIS)

Miller, S.F.; Thompson, M.D.; Glennon, M.A.

1997-04-01

Initial investigations conducted by the U.S. Department of Energy, Chicago Operations Office, and by Argonne National Laboratory used seismic refraction profiling, electrical resistivity depth sounding, conductivity profiling, magnetic gradiometry, and ground-penetrating radar to study environmental geophysics in the area of the Battelle West Jefferson site's radiologically contaminated retired filter beds. The investigators used a combination of nonintrusive technologies and innovative drilling techniques to assess environmental risk at the filter beds and to improve understanding of the geology of the Big Darby Creek floodplain. The geophysical investigation, which showed that the preferred groundwater pathway is associated with a laterally extensive deposit of silty sand to sand that is less than 12 ft deep in the floodplain area, also guided the location of cone penetrometer test sites and piezometer installation. Cone penetrometer testing was useful for comparing continuous logging data with surface geophysical data in establishing correlations among unconsolidated materials

Final environmental impact statement supplement for wastewater management systems, North Jefferson County, Kentucky wastewater facilities

International Nuclear Information System (INIS)

1992-12-01

The Final Environmental Impact Statement Supplement (FEISS) serves to update the wastewater treatment alternatives presented in the original EIS (The North County Area Environmental Impact Statement, Jefferson County, KY, July 1984), determine the best alternative, and compare that alternative to the Louisville and Jefferson County Metropolitan Sewer District's North County Action Plan (NCAP). The NCAP was determined to have the greatest cost effectiveness, lowest environmental impact, and best implementability and reliability and so is the preferred alternative in the FEISS. Significant environmental impacts of the alternative are described and mitigative measures discussed

Present status of tandem accelerator analysis facility in National Institute for Environmental Studies

Energy Technology Data Exchange (ETDEWEB)

Kume, Hiroshi; Shibata, Yasuyuki; Tanaka, Atsushi; Yoneda, Minoru; Kumamoto, Yuichiro; Uehiro, Takashi; Morita, Masatoshi [National Inst. for Environmental Studies, Tsukuba, Ibaraki (Japan)

1996-12-01

In National Institute for Environmental Studies, two types of tandem accelerator analysis facilities were able to be installed in September, 1995. One is the accelerator mass analysis exclusive equipment with a 5 MV tandem accelerator, and the other is the high energy ion beam analyzer, in which the surface analysis system is connected to a 1 MV tandem accelerator, mainly used for PIXE measurement. The accelerator mass analyzer can be roughly divided into four parts, that is, ion source and negative ion injection system, accelerator, high energy analysis system, minute amount isotope beam line and control system. These parts are briefly explained. The test measurement of carbon isotope ratio was carried out, but the results dispersed and unsatisfactory. As for the ion beam analyzer, the surface analysis system (RBS400) of Charles Evans and Associates is combined with a 1 MV PELETRON tandem accelerator (3SDH) of NEC, and these are described. This analyzer also is not in the state that the steady operation can be carried out. Slight leak occurred in the ion source. The countermeasures to both cases are in progress. (K.I.)

The South African National Accelerator Centre and its research programme

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Y. [Kyushu Univ., Fukuoka (Japan)

1997-03-01

An overview of the South African National Accelerator Centre and its research activities is given with emphasis on medium energy nuclear physics and nuclear data measurements for medical use. Also presented is a preliminary result of {sup 40}Ca(p,p`x) spectrum measurement for 392 MeV which has been carried out at RCNP, Osaka University, under the South Africa-Japan collaborative programme. (author)

R and D PROPOSAL FOR THE NATIONAL MUON ACCELERATOR PROGRAM

International Nuclear Information System (INIS)

Zisman, Michael S.; Geer, Stephen

2010-01-01

This document contains a description of a multi-year national R and amp;D program aimed at completing a Design Feasibility Study (DFS) for a Muon Collider and, with international participation, a Reference Design Report (RDR) for a muon-based Neutrino Factory. It also includes the supporting component development and experimental efforts that will inform the design studies and permit an initial down-selection of candidate technologies for the ionization cooling and acceleration systems. We intend to carry out this plan with participants from the host national laboratory (Fermilab), those from collaborating U.S. national laboratories (ANL, BNL, Jlab, LBNL, and SNAL), and those from a number of other U.S. laboratories, universities, and SBIR companies. The R and D program that we propose will provide the HEP community with detailed information on future facilities based on intense beams of muons--the Muon Collider and the Neutrino Factory. We believe that these facilities offer the promise of extraordinary physics capabilities. The Muon Collider presents a powerful option to explore the energy frontier and the Neutrino Factory gives the opportunity to perform the most sensitive neutrino oscillation experiments possible, while also opening expanded avenues for the study of new physics in the neutrino sector. The synergy between the two facilities presents the opportunity for an extremely broad physics program and a unique pathway in accelerator facilities. Our work will give clear answers to the questions of expected capabilities and performance of these muon-based facilities, and will provide defensible ranges for their cost. This information, together with the physics insights gained from the next-generation neutrino and LHC experiments, will allow the HEP community to make well-informed decisions regarding the optimal choice of new facilities. We believe that this work is a critical part of any broad strategic program in accelerator R and D and, as the P5 panel has

An overview of recent nucleon spin structure measurements at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Allada, Kalyan [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2016-02-01

Jefferson Lab have made significant contributions to improve our knowledge of the longitudinal spin structure by measuring polarized structure functions, g1 and g2, down to Q2 = 0.02 GeV2. The low Q2 data is especially useful in testing the Chiral Perturbation theory (cPT) calculations. The spin-dependent sum rules and the spin polarizabilities, constructed from the moments of g1 and g2, provide an important tool to study the longitudinal spin structure. We will present an overview of the experimental program to measure these structure functions at Jefferson Lab, and present some recent results on the neutron polarizabilities, proton g1 at low Q2, and proton and neutron d2 measurement. In addition to this, we will discuss the transverse spin structure of the nucleon which can be accessed using chiral-odd transversity distribution (h1), and show some results from measurements done on polarized 3He target in Hall A.

Chemical, physical, profile and other oceanographic data collected aboard NOAA Ship THOMAS JEFFERSON in the Gulf of Mexico from 2010-06-03 to 2010-07-18 in response to the Deepwater Horizon Oil Spill event (NODC Accession 0069082)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Chemical, physical, profile, tows and underway oceanographic data were collected aboard NOAA Ship THOMAS JEFFERSON in the Gulf of Mexico from 2010-06-03 to...

Acceleration of polarized protons and deuterons in the ion collider ring of JLEIC

Science.gov (United States)

Kondratenko, A. M.; Kondratenko, M. A.; Filatov, Yu N.; Derbenev, Ya S.; Lin, F.; Morozov, V. S.; Zhang, Y.

2017-07-01

The figure-8-shaped ion collider ring of Jefferson Lab Electron-Ion Collider (JLEIC) is transparent to the spin. It allows one to preserve proton and deuteron polarizations using weak stabilizing solenoids when accelerating the beam up to 100 GeV/c. When the stabilizing solenoids are introduced into the collider’s lattice, the particle spins precess about a spin field, which consists of the field induced by the stabilizing solenoids and the zero-integer spin resonance strength. During acceleration of the beam, the induced spin field is maintained constant while the resonance strength experiences significant changes in the regions of “interference peaks”. The beam polarization depends on the field ramp rate of the arc magnets. Its component along the spin field is preserved if acceleration is adiabatic. We present the results of our theoretical analysis and numerical modeling of the spin dynamics during acceleration of protons and deuterons in the JLEIC ion collider ring. We demonstrate high stability of the deuteron polarization in figure-8 accelerators. We analyze a change in the beam polarization when crossing the transition energy.

Compressing Control System Data for Efficient Storage and Retrieval

International Nuclear Information System (INIS)

Christopher Larrieu

2003-01-01

The controls group at the Thomas Jefferson National Accelerator Facility (Jefferson Lab), acquires multiple terabytes of EPICS control system data per year via CZAR, its new archiving system. By heuristically applying a combination of rudimentary compression techniques, in conjunction with several specialized data transformations and algorithms, the CZAR storage engine reduces the size of this data by approximately 88 percent, without any loss of information. While the compression process requires significant memory and processor time, the decompression routine suffers only slightly in this regard

Calibration of a neutron polarimeter in the 0.2-1.1GeV region

International Nuclear Information System (INIS)

Semenov, A.Yu.; Zhang, W.M.; Madey, R.; Ahmidouch, A.; Anderson, B.D.; Assamagan, K.; Avery, S.; Baldwin, A.R.; Crowell, A.S.; Eden, T.; Manley, D.M.; Markowitz, P.; Milleret, G.; Prout, D.; Reichelt, T.; Semenova, I.A.; Ulmer, P.E.; Voutier, E.; Watson, J.W.; Wells, S.P.

2006-01-01

We measured the analyzing power and the efficiency of a neutron polarimeter at the Saturne National Laboratory in France with central energies of the neutron beam of 261,533,752,922, and 1057MeV. This polarimeter was a prototype designed to measure G E n , the neutron electric form factor, at the Thomas Jefferson National Accelerator Facility

A Green Fabry-Perot Cavity for Jefferson Lab Hall A Compton Polarimetry

International Nuclear Information System (INIS)

Rakhman, Abdurahim; Souder, Paul; Nanda, Sirish

2009-01-01

A green laser (CW, 532 nm) based Fabry-Perot cavity for high precision Compton Polarimetry is under development in Hall A of the Jefferson Laboratory. In this paper, we present the principle and the preliminary studies for our test cavity.

Chemical, physical and profile oceanographic data collected aboard NOAA Ship THOMAS JEFFERSON in the Gulf of Mexico from 2010-06-15 to 2010-06-28 in response to the Deepwater Horizon Oil Spill event (NODC Accession 0069083)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Chemical, physical and profile oceanographic data were collected aboard NOAA Ship THOMAS JEFFERSON in the Gulf of Mexico from 2010-06-15 to 2010-06-28 in response to...

Proposed medical applications of the National Accelerator Centre facilities

International Nuclear Information System (INIS)

Jones, D.T.L.

1982-01-01

The National Accelerator Centre is at present under construction at Faure, near Cape Town. The complex will house a 200 MeV separated-sector cyclotron which will provide high quality beams for nuclear physics and related diciplines as well as high intensity beams for medical use. The medical aspects catered for will include particle radiotherapy, isotope production and possibly proton radiography. A 30-bed hospital is to be constructed on the site. Building operations are well advanced and the medical facilities should be available for use by the end of 1984

2016 Accelerators meeting

International Nuclear Information System (INIS)

Spiro, Michel; Revol, Jean-Luc; Biarrotte, Jean-Luc; Napoly, Olivier; Jardin, Pascal; Chautard, Frederic; Thomas, Jean Charles; Petit, Eric

2016-09-01

The Accelerators meeting is organised every two years by the Accelerators division of the French Society of Physics (SFP). It brings together about 50 participants during a one-day meeting. The morning sessions are devoted to scientific presentations while the afternoon is dedicated to technical visits of facilities. This document brings together the available presentations (slides): 1 - Presentation of the Ganil - Grand accelerateur national d'ions lourds/Big national heavy-ion accelerator, Caen (Jardin, Pascal); 2 - Presentation of the Accelerators division of the French Society of Physics (Revol, Jean-Luc); 3 - Forward-looking and Prospective view (Napoly, Olivier); 4 - Accelerators at the National Institute of Nuclear and particle physics, situation, Forward-looking and Prospective view (Biarrotte, Jean-Luc); 5 - GANIL-SPIRAL2, missions and goals (Thomas, Jean Charles); 6 - The SPIRAL2 project (Petit, Eric)

Transcribing Gail Jefferson: The 1977 Boston talk as it actually was

DEFF Research Database (Denmark)

Nevile, Maurice Richard

2015-01-01

A talk by Gail Jefferson, one of the founders of Conversation Analysis, has been recently made available, and Maurice Nevile undertook to transcribe it for the benefit of the language-in-interaction community. Here he reports on what it meant to him, and what we can all get out of such a powerful...

Beam stability of cyclotron accelerator for therapy at National Cancer Center Hospital East

International Nuclear Information System (INIS)

Nishio, T.; Ogino, T.; Shinbo, M.; Ikeda, H.; Tachikawa, T.; Kumata, Y.

2000-01-01

In 1997, the proton-treatment facility that has the therapeutic AVF cyclotron accelerator (C235), is constructed at National Cancer Center Hospital East. The facility has 3-irradiation ports (rooms) that are 2-rotationg gantry ports and 1-horizontal fixed port. The C235 can accelerate proton to 235 MeV with the beam intensity of 300 nA. The external diameter is a very compact with about 4 m. The radio frequency is 106 MHz, the accelerating voltage is about 60 kV, and the harmonic number is 4. A beam stability of the C235 has an important relation with the uniformity of an irradiation field and is a very difficulty. The measured result indicated that the incident beam position must be into the 0.5-mmφ circle. (author)

RF linear accelerators

CERN Document Server

Wangler, Thomas P

2008-01-01

Thomas P. Wangler received his B.S. degree in physics from Michigan State University, and his Ph.D. degree in physics and astronomy from the University of Wisconsin. After postdoctoral appointments at the University of Wisconsin and Brookhaven National Laboratory, he joined the staff of Argonne National Laboratory in 1966, working in the fields of experimental high-energy physics and accelerator physics. He joined the Accelerator Technology Division at Los Alamos National Laboratory in 1979, where he specialized in high-current beam physics and linear accelerator design and technology. In 2007

Doubling Beam Intensity Unlocks Rare Opportunities for Discovery at Fermi National Accelerator Laboratory

International Nuclear Information System (INIS)

Segui, Jennifer A.

2014-01-01

Particle accelerators such as the Booster synchrotron at the Fermi National Accelerator Laboratory (FNAL) produce high-intensity proton beams for particle physics experiments that can ultimately reveal the secrets of the universe. High-intensity proton beams are required by experiments at the ''intensity frontier'' of particle physics research, where the availability of more particles improves the chances of observing extremely rare physical processes. In addition to their central role in particle physics experiments, particle accelerators have found widespread use in industrial, nuclear, environmental, and medical applications. RF cavities are essential components of particle accelerators that, depending on the design, can perform multiple functions, including bunching, focusing, decelerating, and accelerating a beam of charged particles. Engineers are working to model the RF cavities required for upgrading the 40-year old Booster synchrotron. It is a rather complicated process to refurbish, test, and qualify the upgraded RF cavities to sustain an increased repetition rate of the RF field required to produce proton beams at double the current intensity. Both multiphysics simulation and physical measurements are used to evaluate the RF, thermal, and mechanical properties of the Booster RF cavities.

Overview of SNS Cryomodule Performance

CERN Document Server

Drury, Michael A; Davis, Kirk; Delayen, Jean R; Grenoble, Christiana; Hicks, William R; King, Larry; Plawski, Tomasz; Powers, Tom; Preble, Joseph P; Wang, Haipeng; Wiseman, Mark

2005-01-01

Thomas Jefferson National Accelerating Facility (Jefferson Lab) has completed production of 24 Superconducting Radio Frequency (SRF) cryomodules for the Spallation Neutron Source (SNS) superconducting linac. This includes one medium-beta (0.61) prototype, eleven medium-beta and twelve high-beta (0.81) production cryomodules. Ten medium-beta cryomodules as well as two high beta cryomodules have undergone complete operational performance testing in the Cryomodule Test Facility at Jefferson Lab. The set of tests includes measurements of maximum gradient, unloaded Q (Q0), microphonics, and response to Lorentz forces. The Qext's of the various couplers are measured and the behavior of the higher order mode couplers is examined. The mechanical and piezo tuners are also characterized. The results of these performance tests will be discussed in this paper.

Use of accelerators in the national economy

International Nuclear Information System (INIS)

Skrinskij, A.

1984-01-01

Accelerators generating beams of accelerated particles are the basic component of apparatus used in irradiation technologies. One of the basic trends in irradiation is the improvement of materials, mainly polyethylene and other plastics. Irradiation with accelerated electrons improves their mechanical properties and chemical and heat resistance. Accelerated beams are also used in cement production and in grain disinfestation. The use is being developed of synchrotron radiation for rapid analysis of mineral samples, the manufacture of integrated circuits and for other applications. (Ha)

CHALLENGES ENCOUNTERED DURING THE PROCESSING OF THE BNL ERL 5 CELL ACCELERATING CAVITY

Energy Technology Data Exchange (ETDEWEB)

BURRILL,A.

2007-06-25

One of the key components for the Energy Recovery Linac being built by the Electron cooling group in the Collider Accelerator Department is the 5 cell accelerating cavity which is designed to accelerate 2 MeV electrons from the gun up to 15-20 MeV, allow them to make one pass through the ring and then decelerate them back down to 2 MeV prior to sending them to the dump. This cavity was designed by BNL and fabricated by AES in Medford, NY. Following fabrication it was sent to Thomas Jefferson Lab in VA for chemical processing, testing and assembly into a string assembly suitable for shipment back to BNL for integration into the ERL. The steps involved in this processing sequence will be reviewed and the deviations from processing of similar SRF cavities will be discussed. The lessons learned from this process are documented to help future projects where the scope is different from that normally encountered.

Challenges Encountered during the Processing of the BNL ERL 5 Cell Accelerating Cavity

Energy Technology Data Exchange (ETDEWEB)

A. Burrill; I. Ben-Zvi; R. Calaga; H. Hahn; V. Litvinenko; G. T. McIntyre; P. Kneisel; J. Mammosser; J. P. Preble; C. E. Reece; R. A. Rimmer; J. Saunders

2007-08-01

One of the key components for the Energy Recovery Linac being built by the Electron cooling group in the Collider Accelerator Department is the 5 cell accelerating cavity which is designed to accelerate 2 MeV electrons from the gun up to 15-20 MeV, allow them to make one pass through the ring and then decelerate them back down to 2 MeV prior to sending them to the dump. This cavity was designed by BNL and fabricated by AES in Medford, NY. Following fabrication it was sent to Thomas Jefferson Lab in VA for chemical processing, testing and assembly into a string assembly suitable for shipment back to BNL and integration into the ERL. The steps involved in this processing sequence will be reviewed and the deviations from processing of similar SRF cavities will be discussed. The lessons learned from this process are documented to help future projects where the scope is different from that normally encountered.

Low Energy Accelerator Laboratory Technical Area 53, Los Alamos National Laboratory. Environmental assessment

International Nuclear Information System (INIS)

1995-04-01

This Environmental Assessment (EA) analyzes the potential environmental impacts that would be expected to occur if the Department of Energy (DOE) were to construct and operate a small research and development laboratory building at Technical Area (TA) 53 at the Los Alamos National Laboratory (LANL), Los Alamos, New Mexico. DOE proposes to construct a small building to be called the Low Energy Accelerator Laboratory (LEAL), at a previously cleared, bladed, and leveled quarter-acre site next to other facilities housing linear accelerator research activities at TA-53. Operations proposed for LEAL would consist of bench-scale research, development, and testing of the initial section of linear particle accelerators. This initial section consists of various components that are collectively called an injector system. The anticipated life span of the proposed development program would be about 15 years

Proposed Casey's Pond Improvement Project, Fermi National Accelerator Laboratory

International Nuclear Information System (INIS)

1995-05-01

The U.S. Department of Energy (DOE) has prepared an Environmental Assessment (EA), evaluating the impacts associated with the proposed Casey's Pond Improvement Project at the Fermi National Accelerator Laboratory (Fermilab) in Batavia, Illinois. The improvement project would maximize the efficiency of the Fermilab Industrial Cooling Water (ICW) distribution system, which removes (via evaporation) the thermal load from experimental and other support equipment supporting the high energy physics program at Fermilab. The project would eliminate the risk of overheating during fixed target experiments, ensure that the Illinois Water Quality Standards are consistently achieved and provide needed additional water storage for fire protection. Based on the analysis in the EA, the DOE has determined that the proposed action does not constitute a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an Environmental Impact Statement is not required

Present state of studies on FFAG accelerator for radiotherapy of cancer in National Institute of Radiological Sciences

International Nuclear Information System (INIS)

Misu, Toshiyuki

2003-01-01

From 2001, developmental contract studies with Ministry of Education, Culture, Sports, Science and Technology for a compact accelerator for heavy ion radiotherapy of cancer started in National Institute of Radiological Sciences (NIRS) with use of fixed field alternating gradient (FFAG) accelerator, which had been developed in High Energy Accelerator Research Organization (KEK). This paper describes the present state of those studies. Described are FFAG accelerator design for repeated acceleration for 200 Hz or more toward the carbon ion at 400 MeV/u with the range of 25 cm in water, FFAG optical systems for these purposes by linear analyses, and the present situation of the design. Technological problems yielded and future study plan are also commented. (N.I.)

Software engineering practices for control system reliability

International Nuclear Information System (INIS)

S. K. Schaffner; K. S White

1999-01-01

This paper will discuss software engineering practices used to improve Control System reliability. The authors begin with a brief discussion of the Software Engineering Institute's Capability Maturity Model (CMM) which is a framework for evaluating and improving key practices used to enhance software development and maintenance capabilities. The software engineering processes developed and used by the Controls Group at the Thomas Jefferson National Accelerator Facility (Jefferson Lab), using the Experimental Physics and Industrial Control System (EPICS) for accelerator control, are described. Examples are given of how their procedures have been used to minimized control system downtime and improve reliability. While their examples are primarily drawn from their experience with EPICS, these practices are equally applicable to any control system. Specific issues addressed include resource allocation, developing reliable software lifecycle processes and risk management

TL dosimetry in the new Tandetron ion accelerator site of the National Institute of Nuclear Research (ININ)

International Nuclear Information System (INIS)

Valdovinos A, M.; Gonzalez M, P.R.

2000-01-01

The National Institute of Nuclear Research (ININ) acquired a positive ions accelerator type Tandetron 2 MV of the dutch company High Voltage Engineering, Europe B.V., which was finished its installation this year (2000) in an already existing building in the Dr. Nabor Carrillo Flores Nuclear Centre, where it was prepared for the following purposes: the accelerator will be used to realize research through X-ray emission induced by charged particles, Rutherford backscattering analysis, nuclear reaction analysis, gamma ray emission induced by charged particles, resonant dispersion analysis, elastic backward detection analysis and by particle canalization analysis. The accelerator consists of an injection system with two ion sources, ion accelerator tank with voltage in terminal at 2 MV, recovery and recirculation system of charge interchange gas, iman selector analyzer system and with high energy focussing, control system through computer and management and recovery of isolator gas system. For the realization of operation tests of this accelerator, it was had the license authorizing by the National Commission of Nuclear Safety and Safeguards (CNSNS). During the test stage Tl dosemeters were arranged in the Tandetron accelerator area, and also in direction to the beam outlet. In this work, are presented the obtained results of the measurement of radiation levels, as in the area as in the beam outlet. (Author)

Polarimetry of the polarized hydrogen deuteride HDice target under an electron beam

Energy Technology Data Exchange (ETDEWEB)

Laine, Vivien E. [Blaise Pascal Univ., Aubiere (France)

2013-10-01

The study of the nucleon structure has been a major research focus in fundamental physics in the past decades and still is the main research line of the Thomas Jefferson National Accelerator Facility (Jefferson Lab). For this purpose and to obtain statistically meaningful results, having both a polarized beam and a highly efficient polarized target is essential. For the target, this means high polarization and high relative density of polarized material. A Hydrogen Deuteride (HD) target that presents both such characteristics has been developed first at Brookhaven National Lab (BNL) and brought to the Hall B of Jefferson Lab in 2008. The HD target has been shown to work successfully under a high intensity photon beam (BNL and Jefferson Lab). However, it remained to be seen if the target could stand an electron beam of reasonably high current (nA). In this perspective, the target was tested for the first time in its frozen spin mode under an electron beam at Jefferson Lab in 2012 during the g14 experiment. This dissertation presents the principles and usage procedures of this HD target. The polarimetry of this target with Nuclear Magnetic Resonance (NMR) during the electron beam tests is also discussed. In addition, this dissertation also describes another way to perform target polarimetry with the elastic scattering of electrons off a polarized target by using data taken on helium-3 during the E97-110 experiment that occurred in Jefferson Lab's Hall A in 2003.

Studies of the neutron spin structure at Jefferson Lab

International Nuclear Information System (INIS)

Korsch, W.

2003-01-01

The polarized 3 He program of Hall A at Jefferson Lab will be described. Results on the generalized Gerasimov-Drell-Hearn integral for the neutron in a Q 2 range between 0.02 GeV 2 /c 2 2 2 /c 2 will be presented. Preliminary results of the virtual photon asymmetry A 1 n (x,Q 2 ) and the spin structure function g 2 n (x,Q 2 ) at large values of Bjorken x and low Q 2 , respectively, will be discussed. (orig.)

The Jefferson Lab Frozen Spin Target

Energy Technology Data Exchange (ETDEWEB)

Christopher Keith, James Brock, Christopher Carlin, Sara Comer, David Kashy, Josephine McAndrew, David Meekins, Eugene Pasyuk, Joshua Pierce, Mikell Seely

2012-08-01

A frozen spin polarized target, constructed at Jefferson Lab for use inside a large acceptance spectrometer, is described. The target has been utilized for photoproduction measurements with polarized tagged photons of both longitudinal and circular polarization. Protons in TEMPO-doped butanol were dynamically polarized to approximately 90% outside the spectrometer at 5 T and 200-300 mK. Photoproduction data were acquired with the target inside the spectrometer at a frozen-spin temperature of approximately 30 mK with the polarization maintained by a thin, superconducting coil installed inside the target cryostat. A 0.56 T solenoid was used for longitudinal target polarization and a 0.50 T dipole for transverse polarization. Spin relaxation times as high as 4000 hours were observed. We also report polarization results for deuterated propanediol doped with the trityl radical OX063.

Acceleration of 14C beams in electrostatic accelerators

International Nuclear Information System (INIS)

Rowton, L.J.; Tesmer, J.R.

1981-01-01

Operational problems in the production and acceleration of 14 C beams for nuclear structure research in Los Alamos National Laboratory's Van de Graaff accelerators are discussed. Methods for the control of contamination in ion sources, accelerators and personnel are described. Sputter source target fabrication techniques and the relative beam production efficiencies of various types of bound particulate carbon sputter source targets are presented

Performance of the FEL cryomodules

International Nuclear Information System (INIS)

Drury, M.; Fischer, J.; Preble, J.

1998-01-01

The Thomas Jefferson National Accelerator Facility (Jefferson Lab, formerly known as CEBAF) is building a highly efficient, kilowatt-level infrared free-electron laser, the IR Demo FEL. The IR FEL uses superconducting radio-frequency (SRF) cavities to accelerate the electron beam that provides energy for the laser. These cavities provide the high-gradient acceleration for the high average currents necessary for a compact FEL design. Currently, a quarter cryomodule injector and a full eight-cavity cryomodule have been installed in the FEL linac. These units were tested as part of the IR FEL commissioning process. The main focus of these tests was to determine the maximum stable operating gradient. The average maximum gradient reached by these ten cavities was 11 Mv/m. Other tests include measurement of cavity parameters such as the unloaded Q (Qo) vs. gradient, the input coupling, calibration of field probes and behavior of the tuner mechanisms. This paper presents the results of those tests

Japan Accelerator Conference

International Nuclear Information System (INIS)

Anon.

1989-01-01

At the international level, the high energy accelerator scene evolves rapidly and the International Conference on High Energy Accelerators is where its strong pulse can best be felt. This year, the Conference was held for the first time in Japan, with the 14th meeting in the series having been hosted in August by the Japanese KEK National Laboratory for High Energy Physics, Tsukuba. The venue was a recognition of the premier accelerator physics and technology status achieved by this diligent nation

Japan Accelerator Conference

Energy Technology Data Exchange (ETDEWEB)

Anon.

1989-11-15

At the international level, the high energy accelerator scene evolves rapidly and the International Conference on High Energy Accelerators is where its strong pulse can best be felt. This year, the Conference was held for the first time in Japan, with the 14th meeting in the series having been hosted in August by the Japanese KEK National Laboratory for High Energy Physics, Tsukuba. The venue was a recognition of the premier accelerator physics and technology status achieved by this diligent nation.

Testing and interfacing intelligent power supplies for the Los Alamos National Laboratory Accelerator Complex

International Nuclear Information System (INIS)

Sturrock, J.C.; Cohen, S.; Weintraub, B.L.; Hayden, D.J.; Archuleta, S.F.

1992-01-01

New high-current, high-precision microprocessor-controlled power supplies, built by Alpha Scientific Electronics of Hayward, CA, have been installed at the Los Alamos National Laboratory Accelerator Complex. Each unit has sophisticated microprocessor control on-board and communicates via RS-422 (serial communications). The units use a high level ASCII-based control protocol. Performance tests were conducted to verify adherence to specification and to ascertain ultimate long-term stability. The ''front-end'' software used by the accelerator control system has been written to accommodate these new devices. The supplies are interfaced to the control system through a terminal server port connected to the site-wide ediernet backbone. Test design and results as well as details of the software implementation for the analog and digital control of the supplies through the accelerator control system are presented

Analysis of the Qualification-Tests Performance of the Superconducting Cavities for the SNS Linac

CERN Document Server

Delayen, J R; Ozelis, O

2004-01-01

Thomas Jefferson National Accelerating Facility (Jefferson Lab) is producing superconducting radio frequency (SRF) cryomodules for the Spallation Neutron Source (SNS) cold linac. This consists of 11 medium-beta (β=0.61) cyomodules of 3 cavities each, and 12 high-beta (β=0.81) cryomodules of 4 cavities each. Before assembly into cavity strings the cavities undergo individual qualification tests in a vertical cryostat (VTA). In this paper we analyze the performance of the cavities during these qualification tests, and attempt to correlate this performance with cleaning, assembly, and testing procedures. We also compare VTA performance with performance in completed cryomodules.

Accelerating Innovation that Enhances Resource Recovery in the Wastewater Sector: Advancing a National Testbed Network.

Science.gov (United States)

Mihelcic, James R; Ren, Zhiyong Jason; Cornejo, Pablo K; Fisher, Aaron; Simon, A J; Snyder, Seth W; Zhang, Qiong; Rosso, Diego; Huggins, Tyler M; Cooper, William; Moeller, Jeff; Rose, Bob; Schottel, Brandi L; Turgeon, Jason

2017-07-18

This Feature examines significant challenges and opportunities to spur innovation and accelerate adoption of reliable technologies that enhance integrated resource recovery in the wastewater sector through the creation of a national testbed network. The network is a virtual entity that connects appropriate physical testing facilities, and other components needed for a testbed network, with researchers, investors, technology providers, utilities, regulators, and other stakeholders to accelerate the adoption of innovative technologies and processes that are needed for the water resource recovery facility of the future. Here we summarize and extract key issues and developments, to provide a strategy for the wastewater sector to accelerate a path forward that leads to new sustainable water infrastructures.

Overview of SNS Cryomodule Performance

International Nuclear Information System (INIS)

Michael Drury; Edward Daly; Christiana Grenoble; William Hicks; Lawrence King; Tomasz Plawski; Thomas Powers; Joseph Preble; Haipeng Wang; Mark Wiseman; G. Davis; Jean Delayen

2005-01-01

Thomas Jefferson National Accelerating Facility (Jefferson Lab) has completed production of 24 Superconducting Radio Frequency (SRF) cryomodules for the Spallation Neutron Source (SNS) superconducting linac. This includes one medium-β (0.61) prototype, eleven medium-β and twelve high-β (0.81) production cryomodules. Nine medium-β cryomodules as well as two high-β cryomodules have undergone complete operational performance testing in the Cryomodule Test Facility at Jefferson Lab. The set of tests includes measurements of maximum gradient, unloaded Q (Q 0 ), microphonics, and response to Lorentz forces. The Q ext 's of the various couplers are measured and the behavior of the higher order mode couplers is examined. The mechanical and piezo tuners are also characterized. The results of these performance tests will be discussed in this paper

Design and Manufacture of the Conduction Cooled Torus Coils for The Jefferson Laboratory 12-GeV Upgrade

Energy Technology Data Exchange (ETDEWEB)

Wiseman, M. [Jefferson Lab; Elementi, L. [Fermilab; Elouadhiri, L. [Jefferson Lab; Gabrielli, G. [Fermilab; Gardner, T. J. [Fermilab; Ghoshal, P. K. [Jefferson Lab; Kashy, D. [Jefferson Lab; Kiemschies, O. [Fermilab; Krave, S. [Fermilab; Makarov, A. [Fermilab; Robotham, B. [Fermilab; Szal, J. [Fermilab; Velev, G. [Fermilab

2015-01-01

The design of the 12-GeV torus required the construction of six superconducting coils with a unique geometry required for the experimental needs of Jefferson Laboratory Hall B. Each of these coils consists of 234 turns of copper-stabilized superconducting cable conduction cooled by 4.6 K helium gas. The finished coils are each roughly 2 × 4 × 0.05 m and supported in an aluminum coil case. Because of its geometry, new tooling and manufacturing methods had to be developed for each stage of construction. The tooling was designed and developed while producing a practice coil at Fermi National Laboratory. This paper describes the tooling and manufacturing techniques required to produce the six production coils and two spare coils required by the project. Project status and future plans are also presented.

78 FR 33051 - Non-Rock Alternatives to Shoreline Protection Demonstration Project (LA-16) Iberia, Jefferson...

Science.gov (United States)

2013-06-03

... DEPARTMENT OF AGRICULTURE Natural Resources Conservation Service Non-Rock Alternatives to...-Rock Alternatives to Shoreline Protection Demonstration Project (LA-16), Iberia, Jefferson, and... and environmental limitations preclude the use of rock structures. The shoreline protection systems...

Physics Opportunities with the 12 GeV Upgrade at Jefferson Lab

International Nuclear Information System (INIS)

Dudek, Jozef; Ent, Rolf; Essig, Rouven; Kumar, Krishna; Meyer, Curtis; McKeown, Robert; Meziani, Zein Eddine; Miller, Gerald A.; Pennington, Michael; Richards, David; Weinstein, Larry; Young, Glenn

2012-01-01

We are at the dawn of a new era in the study of hadronic nuclear physics. The non-Abelian nature of Quantum Chromodynamics (QCD) and the resulting strong coupling at low energies represent a significant challenge to nuclear and particle physicists. The last decade has seen the development of new theoretical and experimental tools to quantitatively study the nature of confinement and the structure of hadrons comprised of light quarks and gluons. Together these will allow both the spectrum and the structure of hadrons to be elucidated in unprecedented detail. Exotic mesons that result from excitation of the gluon field will be explored. Multidimensional images of hadrons with great promise to reveal the dynamics of the key underlying degrees of freedom will be produced. In particular, these multidimensional distributions open a new window on the elusive spin content of the nucleon through observables that are directly related to the orbital angular momenta of quarks and gluons. Moreover, computational techniques in Lattice QCD now promise to provide insightful and quantitative predictions that can be meaningfully confronted with, and elucidated by, forthcoming experimental data. In addition, the development of extremely high intensity, highly polarized and extraordinarily stable beams of electrons provides innovative opportunities for probing (and extending) the Standard Model, both through parity violation studies and searches for new particles. Thus the 12 GeV upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab will enable a new experimental program with substantial discovery potential to address these and other important topics in nuclear, hadronic and electroweak physics.

Physics Opportunities with the 12 GeV Upgrade at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Dudek, Jozef; Essig, Rouven; Kumar, Krishna; Meyer, Curtis; McKeown, Robert; Meziani, Zein Eddine; Miller, Gerald A; Pennington, Michael; Richards, David; Weinstein, Larry

2012-08-01

We are at the dawn of a new era in the study of hadronic nuclear physics. The non-Abelian nature of Quantum Chromodynamics (QCD) and the resulting strong coupling at low energies represent a significant challenge to nuclear and particle physicists. The last decade has seen the development of new theoretical and experimental tools to quantitatively study the nature of confinement and the structure of hadrons comprised of light quarks and gluons. Together these will allow both the spectrum and the structure of hadrons to be elucidated in unprecedented detail. Exotic mesons that result from excitation of the gluon field will be explored. Multidimensional images of hadrons with great promise to reveal the dynamics of the key underlying degrees of freedom will be produced. In particular, these multidimensional distributions open a new window on the elusive spin content of the nucleon through observables that are directly related to the orbital angular momenta of quarks and gluons. Moreover, computational techniques in Lattice QCD now promise to provide insightful and quantitative predictions that can be meaningfully confronted with, and elucidated by, forthcoming experimental data. In addition, the development of extremely high intensity, highly polarized and extraordinarily stable beams of electrons provides innovative opportunities for probing (and extending) the Standard Model, both through parity violation studies and searches for new particles. Thus the 12 GeV upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab will enable a new experimental program with substantial discovery potential to address these and other important topics in nuclear, hadronic and electroweak physics.

76 FR 18753 - Jefferson Island Storage & Hub, L.L.C.; Notice of Filing

Science.gov (United States)

2011-04-05

... notification when a document is added to a subscribed docket(s). For assistance with any FERC Online service... services provided under section 311 of the Natural Gas Policy Act of 1978 (``NGPA''). Jefferson Island proposes to revise its SOC to provide its customers the option to use pooling points as additional points...

Measurement Of Neutron Radius In Lead By Parity Violating Scattering Flash ADC DAQ

Energy Technology Data Exchange (ETDEWEB)

Ahmed, Zafar [Christopher Newport Univ., Newport News, VA (United States)

2012-06-01

This dissertation reports the experiment PREx, a parity violation experiment which is designed to measure the neutron radius in ²⁰⁸Pb. PREx is performed in hall A of Thomas Jefferson National Accelerator Facility from March 19th to June 21st. Longitudionally polarized electrons at energy 1 GeV scattered at and angle of θ_lab = 5.8 ° from the Lead target. Beam corrected pairty violaing counting rate asymmetry is (A_corr= 594 ± 50(stat) ± 9(syst))ppb at Q² = 0.009068GeV ². This dissertation also presents the details of Flash ADC Data Acquisition(FADC DAQ) system for Moller polarimetry in Hall A of Thomas Jefferson National Accelerator Facility. The Moller polarimeter measures the beam polarization to high precision to meet the specification of the PREx(Lead radius experiment). The FADC DAQ is part of the upgrade of Moller polarimetery to reduce the systematic error for PREx. The hardware setup and the results of the FADC DAQ analysis are presented

Temperature and salinity profiles from CTD casts from NOAA Ship THOMAS JEFFERSON and other PLATFORMS from the North/South Pacific Ocean, North Atlantic Ocean, and other sea areas in support of the Integrated Global Ocean Services System (IGOSS) from 1991-11-01 to 1991-11-30 (NODC Accession 9100243)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — CTD and other data were collected from NOAA Ship THOMAS JEFFERSON and other PLATFORMS in support of the Integrated Global Ocean Services System (IGOSS). Data were...

Illinois Accelerator Research Center

Science.gov (United States)

Kroc, Thomas K.; Cooper, Charlie A.

The Illinois Accelerator Research Center (IARC) hosts a new accelerator development program at Fermi National Accelerator Laboratory. IARC provides access to Fermi's state-of-the-art facilities and technologies for research, development and industrialization of particle accelerator technology. In addition to facilitating access to available existing Fermi infrastructure, the IARC Campus has a dedicated 36,000 ft2 Heavy Assembly Building (HAB) with all the infrastructure needed to develop, commission and operate new accelerators. Connected to the HAB is a 47,000 ft2 Office, Technology and Engineering (OTE) building, paid for by the state, that has office, meeting, and light technical space. The OTE building, which contains the Accelerator Physics Center, and nearby Accelerator and Technical divisions provide IARC collaborators with unique access to world class expertise in a wide array of accelerator technologies. At IARC scientists and engineers from Fermilab and academia work side by side with industrial partners to develop breakthroughs in accelerator science and translate them into applications for the nation's health, wealth and security.

Development of a Bunched Beam Electron Cooler based on ERL and Circulator Ring Technology for the Jefferson Lab Electron-Ion Collider

Energy Technology Data Exchange (ETDEWEB)

Benson, Stephen V. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Derbenev, Yaroslav S. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Hannon, Fay E. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Hutton, Andrew M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Li, Rui [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Rimmer, Robert A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Roblin, Yves R. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Wang, Haipeng [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, He [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, Yuhong [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2018-01-01

Jefferson Lab is in the process of designing an electron ion collider with unprecedented luminosity at a 45 GeV center-of-mass energy. This luminosity relies on ion cooling in both the booster and the storage ring of the accelerator complex. The cooling in the booster will use a conventional DC cooler similar to the one at COSY. The high-energy storage ring, operating at a momentum of up to 100 GeV/nucleon, requires novel use of bunched-beam cooling. There are two designs for such a cooler. The first uses a conventional Energy Recovery Linac (ERL) with a magnetized beam while the second uses a circulating ring to enhance both peak and average currents experienced by the ion beam. This presentation will describe the design of both the Circulator Cooling Ring (CCR) design and that of the backup option using the stand-alone ERL operated at lower charge but higher repetition rate than the ERL injector required by the CCR-based design.

A Measurement of GE^n at High Momentum Transfer in Hall A

Science.gov (United States)

Feuerbach, Robert J.; Wojtsekhowski, Bogdan

2006-10-01

A precision measurement of the electric form-factor of the neutron, GE^n, at Q^2 up to 3.5 GeV^2 was recently completed in Hall A at the Thomas Jefferson National Accelerator Facility(Jefferson Lab). The ratio GE^n/GM^n was measured through the beam-target asymmetry A of electrons quasi-elastically scattered off neutrons in the reaction ^3He(e,e' n). The experiment took advantage of recent developments of the electron beam and target, as well as two detectors new to Jefferson Lab. The measurement used the accelerator's 100% duty-cycle high-polarization (typically 84%) electron beam and a new, hybrid optically-pumped polarized ^3He target which achieved polarizations above 50%. A medium acceptance (80msr) open-geometry magnetic spectrometer (BigBite) detected the scattered electron, while a new neutron detector was constructed to observe the released neutron. An overview of the experiment and the experimental motivation will be discussed, in particular the large range of predictions from modern calculations for GE^n at this relatively high Q^2. Finally, the analysis progress and preliminary results will be presented.

Helicity Asymmetry Measurement for π⁰ Photoproduction with FROST

Energy Technology Data Exchange (ETDEWEB)

Iwamoto, Hideko [George Washington Univ., Washington, DC (United States)

2011-08-15

This thesis reports on the first helicity asymmetry measurement for single neutral pion photoproduction using the CLAS detector in Hall B at the Thomas Jefferson National Accelerator Facility (JLab). This measurement used longitudinally polarized protons and circularly polarized photons at energies between 350 MeV and 2400 MeV. The experimental results are compared to three available model calculations.

Helicity Asymmetry Measurement for pi⁰ Photoproduction with FROST

Energy Technology Data Exchange (ETDEWEB)

Iwamoto, Hideko [George Washington Univ., Washington, DC (United States)

2011-08-15

This thesis reports on the first helicity asymmetry measurement for single neutral pion photoproduction using the CLAS detector in Hall B at the Thomas Jefferson National Accelerator Facility (JLab). This measurement used longitudinally polarized protons and circularly polarized photons at energies between 350 MeV and 2400 MeV. The experimental results are compared to three available model calculations.

The Reverend Thomas Jefferson Bowen: An Introductory Background to His Linguistic Works, 1850-1856

Science.gov (United States)

Awoniyi, Timothy A.

1974-01-01

A historical narrative background for the linguistic works of Thomas Jefferson Bowen, an American missionary who was the first non-Nigerian to publish a grammar of Yoruba (1858). The author points up a need for further scholarly review of Bowen's pioneering work and contribution to Yoruba studies. (JT)

Jefferson Davis and the Failure of Confederate Military Strategy, 1861-1865

Science.gov (United States)

2010-04-14

seventeen. Here he first met some of the men who later held key roles in the Confederate Army: Albert Sidney Johnston, Leonidas Polk, and later Robert...General Lee’s magnificent Army ofNorthem Virginia. Throughout the war Jefferson Davis failed to assign to any theater and entirely subsidiary role ...fight. 24 0 ENDNOTES 1 A. H. McDannald, B.L., ed., The Modern Concise Encyclopedia, vol. III, (New York: Unicorn Press, 1941), 490-491. 2 Harry

Measurement of Polarization Observables in the Electro-Excitation of the Proton to its First Excited State

International Nuclear Information System (INIS)

Rikki Roche

2003-01-01

This thesis reports results from the Thomas Jefferson National Accelerator Facility (Jefferson Lab) Hall A experiment E91-011, which measured double-polarization observables in the pion electroproduction reaction from the proton. Specifically, the experiment measured the recoil proton polarization, polarized response functions, and cross section for the p(rvec e), e(prime) (rvec p) π o reaction at a center-of-mass energy centered at W = 1232 MeV--the peak of the Δ(1232) resonance--and at a four-momentum transfer squared of Q 2 = 1.0 GeV 2 /c 2 . Both the recoil proton polarization and polarized response function results will be presented in this thesis

Quantum efficiency measurement system for large area CsI photodetectors

CERN Document Server

Cusanno, F; Colilli, S; Crateri, R; Fratoni, R; Frullani, S; Garibaldi, F; Giuliani, F; Gricia, M; Lucentini, M; Mostarda, A; Santavenere, F; Veneroni, P; Breuer, H; Iodice, M; Urciuoli, G M; De Cataldo, G; De Leo, R; Lagamba, L; Braem, André

2003-01-01

A proximity focusing freon/CsI RICH detector has been built for kaon physics at Thomas Jefferson National Accelerator Facility (TJNAF or Jefferson Lab), Hall A. The Cherenkov photons are detected by a UV photosensitive CsI film which has been obtained by vacuum evaporation. A dedicated evaporation facility for large area photocathodes has been built for this task. A measuring system has been built to allow the evaluation of the absolute quantum efficiency (QE) just after the evaporation. The evaporation facility is described here, as well as the quantum efficiency measurement device. Results of the QE on-line measurements, for the first time on large area photocathodes, are reported.

Centrally managed name resolution schemes for EPICS

International Nuclear Information System (INIS)

Jun, D.

1997-01-01

The Experimental Physics and Industrial Control System (EPICS) uses a broadcast method to locate resources and controls distributed across control servers. There are many advantages offered by using a centrally managed name resolution method, in which resources are located using a repository. The suitability of DCE Directory Service as a name resolution method is explored, and results from a study involving DCE are discussed. An alternative nameserver method developed and in use at the Thomas Jefferson national Accelerator Facility (Jefferson Lab) is described and results of integrating this new method with existing EPICS utilities presented. The various methods discussed in the paper are compared

Santa Fe Accelerator Conference

International Nuclear Information System (INIS)

Anon.

1983-01-01

The 10th USA National Particle Accelerator Conference was hosted this year by the Los Alamos National Laboratory in Santa Fe from 21-23 March. It was a resounding success in emphasizing the ferment of activity in the accelerator field. About 900 people registered and about 500 papers were presented in invited and contributed talks and poster sessions

76 FR 8808 - Supplemental Final Environmental Impact Statement: Clark County, Indiana, and Jefferson County, KY

Science.gov (United States)

2011-02-15

..., financing, construction, operation and oversight of the Project, and an update to the major project finance... Indiana Ohio River Bridges (Project) in Clark County, Indiana and Jefferson County, Kentucky. FOR FURTHER INFORMATION CONTACT: Mr. Duane Thomas, Project Manager, Federal Highway Administration, John C. Watts Federal...

The spin structure of the nucleon

International Nuclear Information System (INIS)

Deur, A.

2008-02-01

This document describes the recent experimental results on the spin structure of the nucleon obtained with the electron accelerator Thomas Jefferson National Facility (Jefferson Lab), Virginia. We first discuss the goal of studying the nucleon spin structure and give the basis and phenomenology of high energy lepton scattering. Then, we discuss with some details a few sum rules concerning the spin structure of the nucleon. Those are important tools for studying the nucleon spin structure at Jefferson Lab. We then describe the present experimental situation and analyze the results. We have been able to determine an effective coupling constant for the strong interaction for any regime of quantum chromodynamics which proves that QCD is an approximately conformal theory. We conclude on the perspectives for this field of research, in particular with the 12 GeV energy upgrade of Jefferson Lab. The top priority will be the measurement of generalised parton distributions. The only issue that will stay misunderstood is the role of the very low x domain on the spin structure of the nucleon

Cycle-Based Budgeting and Continuous Improvement at Jefferson County Public Schools: Year 1 Report

Science.gov (United States)

Yan, Bo

2016-01-01

This report documents the first-year of implementing Cycle-based Budgeting at Jefferson County Public Schools (Louisville, KY). To address the limitations of incremental budgeting and zero-based budgeting, a Cycle-based Budgeting model was developed and implemented in JCPS. Specifically, each new program needs to submit an on-line budget request…

Beam Transport Devices for the 10 kW IR Free Electron Laser

International Nuclear Information System (INIS)

Lawrence Dillon-Townes; Michael Bevins; David Kashy; Stephanie Slachtouski; Ronald Lassiter; George Neil; Michelle Shinn; Joseph Gubeli; Christopher Behre; David Douglas; David W. Waldman; George Biallas; Lawrence Munk; Christopher Gould

2005-01-01

Beam transport components for the 10kW IR Free Electron Laser (FEL) at Thomas Jefferson National Accelerator Facility (Jefferson Lab) were designed to manage (1) electron beam transport and (2) photon beam transport. An overview of the components will be presented in this paper. The electron beam transport components were designed to address RF heating, maintain an accelerator transport vacuum of 1 x 10 -8 torr, deliver photons to the optical cavity, and provide 50 kW of beam absorption during the energy recovery process. The components presented include a novel shielded bellows, a novel zero length beam clipper, a one decade differential pumping station with a 7.62 cm (3.0 inch) aperture, and a 50 kW beam dump. The photon beam transport components were designed to address the management of photons delivered by the accelerator transport. The optical cavity manages the photons and optical transport delivers the 10 kW of laser power to experimental labs. The optical cavity component presented is a unique high reflector vessel and the optical transport component presented is a turning mirror cassette

Production of Copper-Plated Beamline Bellows and Spools for LCLS-II

Energy Technology Data Exchange (ETDEWEB)

Wilson, Katherine M. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Carpenter, Brian C. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Daly, Ed [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Huque, Naeem A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Peshehonoff, Ted [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Arkan, Tug [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Lunin, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Premo, K. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

2017-05-01

The SLAC National Accelerator Laboratory is currently constructing a major upgrade to its accelerator, the Linac Coherent Light Source II (LCLS-II). Several Department of Energy national laboratories, including the Thomas Jefferson National Accelerator Facility (JLab) and Fermi National Accelerator Laboratory (FNAL), are participating in this project. The 1.3-GHz cryomodules for this project consist of eight cavities separated by bellows (expansion joints) and spools (tube sections), which are copper plated for RF conduction. JLab is responsible for procurement of these bellows and spools, which are delivered to JLab and FNAL for assembly into cryomodules. Achieving accelerator-grade copper plating is always a challenge and requires careful specification of requirements and application of quality control processes. Due to the demanding technical requirements of this part, JLab implemented procurement strategies to make the process more efficient as well as provide process redundancy. This paper discusses the manufacturing challenges that were encountered and resolved, as well as the strategies that were employed to minimize the impact of any technical issues.

Operation of the Brookhaven National Laboratory Accelerator Test Facility

International Nuclear Information System (INIS)

Batchelor, K.; Ben-Zvi, I.; Botke, I.; Chou, T.S.; Fernow, R.; Fischer, J.; Fisher, A.; Gallardo, J.; Ingold, G.; Malone, R.; Palmer, R.; Parsa, Z.; Pogorelsky, I.; Rogers, J.; Sheehan, J.; Srinivasan-Rao, T.; Tsang, T.; Ulc, S.; van Steenbergen, A.; Wang, X.J.; Woodle, M.; Yu, L.H.

1992-01-01

Early operation of the 50 MeV high brightness electron linac of the Accelerator Test Facility is described along with experimental data. This facility is designed to study new linear acceleration techniques and new radiation sources based on linacs in combination with free electron lasers. The accelerator utilizes a photo-excited, metal cathode, radio frequency electron gun followed by two travelling wave accelerating sections and an Experimental Hall for the study program

Los Alamos National Laboratory accelerated tru waste workoff strategies

International Nuclear Information System (INIS)

Kosiewicz, S.T.; Triay, I.R.; Rogers, P.Z.; Christensen, D.V.

1997-01-01

During 1996, the Los Alamos National Laboratory (LANL) developed two transuranic (TRU) waste workoff strategies that were estimated to save $270 - 340M through accelerated waste workoff and the elimination of a facility. The planning effort included a strategy to assure that LANL would have a significant quantity (3000+ drums) of TRU waste certified for shipment to the Waste Isolation Pilot Plant (WIPP) beginning in April of 1998, when WIPP was projected to open. One of the accelerated strategies can be completed in less than ten years through a Total Optimization of Parameters Scenario (open-quotes TOPSclose quotes). open-quotes TOPSclose quotes fully utilizes existing LANL facilities and capabilities. For this scenario, funding was estimated to be unconstrained at $23M annually to certify and ship the legacy inventory of TRU waste at LANL. With open-quotes TOPSclose quotes the inventory is worked off in about 8.5 years while shipping 5,000 drums per year at a total cost of $196M. This workoff includes retrieval from earthen cover and interim storage costs. The other scenario envisioned funding at the current level with some increase for TRUPACT II loading costs, which total $16M annually. At this funding level, LANL estimates it will require about 17 years to work off the LANL TRU legacy waste while shipping 2,500 drums per year to WIPP. The total cost will be $277M. This latter scenario decreases the time for workoff by about 19 years from previous estimates and saves an estimated $190M. In addition, the planning showed that a $70M facility for TRU waste characterization was not needed. After the first draft of the LANL strategies was written, Congress amended the WIPP Land Withdrawal Act (LWA) to accelerate the opening of WIPP to November 1997. Further, the No Migration Variance requirement for the WIPP was removed. This paper discusses the LANL strategies as they were originally developed. 1 ref., 3 figs., 2 tabs

Moeller polarimeter in the hall a jefferson lab after reconstruction

International Nuclear Information System (INIS)

Pomatsalyuk, R.I.

2016-01-01

The Moller polarimeter in the Hall A of Jefferson Lab was reconstructed in order to expand of the energy range of the polarimeter to measure the polarization of the electron beam with an energy up to 11.5 GeV. The paper de-scribes the main results of the Moller polarimeter testing after reconstruction. The measurements of the electrons polarization were provided by two data acquisition systems operating in parallel. The testing of the shielding insertion of magnetic dipole has been performed. The way to eliminate detected deviations in the operation of polarimeter during test is shown.

Diagnostics for induction accelerators

International Nuclear Information System (INIS)

Fessenden, T.J.

1997-01-01

The induction accelerator was conceived by N. C. Christofilos and first realized as the Astron accelerator that operated at Lawrence Livermore National Laboratory (LLNL) from the early 1960s to the end of 1975. This accelerator generated electron beams at energies near 6 MeV with typical currents of 600 Amperes in 400-ns pulses. The Advanced Test Accelerator (ATA) built at Livermore close-quote s Site 300 produced 10,000-Ampere beams with pulse widths of 70 ns at energies approaching 50 MeV. Several other electron and ion induction accelerators have been fabricated at LLNL and Lawrence Berkeley National Laboratory (LBNL). This paper reviews the principal diagnostics developed through efforts by scientists at both laboratories for measuring the current, position, energy, and emittance of beams generated by these high-current, short-pulse accelerators. Many of these diagnostics are closely related to those developed for other accelerators. However, the very fast and intense current pulses often require special diagnostic techniques and considerations. The physics and design of the more unique diagnostics developed for electron induction accelerators are presented and discussed in detail. copyright 1997 American Institute of Physics

Switching the JLab Accelerator Operations Environment from an HP-UX Unix-based to a PC/Linux-based environment

International Nuclear Information System (INIS)

Mcguckin, Theodore

2008-01-01

The Jefferson Lab Accelerator Controls Environment (ACE) was predominantly based on the HP-UX Unix platform from 1987 through the summer of 2004. During this period the Accelerator Machine Control Center (MCC) underwent a major renovation which included introducing Redhat Enterprise Linux machines, first as specialized process servers and then gradually as general login servers. As computer programs and scripts required to run the accelerator were modified, and inherent problems with the HP-UX platform compounded, more development tools became available for use with Linux and the MCC began to be converted over. In May 2008 the last HP-UX Unix login machine was removed from the MCC, leaving only a few Unix-based remote-login servers still available. This presentation will explore the process of converting an operational Control Room environment from the HP-UX to Linux platform as well as the many hurdles that had to be overcome throughout the transition period

Operation of the Brookhaven national laboratory accelerator test facility

International Nuclear Information System (INIS)

Batchelor, K.; Ben-Zvi, I.; Botke, I.; Chou, T.S.; Fernow, R.; Fischer, J.; Fisher, A.; Gallardo, J.; Ingold, G.; Malone, R.; Palmer, R.; Parsa, Z.; Pogorelsky, I.; Rogers, J.; Sheehan, J.; Srinivasan-Rao, T.; Tsang, T.; Ulc, S.; Van Steenbergen, A.; Wang, X.J.; Woodle, M.; Yu, L.H.

1992-01-01

Early operation of the 50 MeV high brightness electron linac of the Accelerator Test Facility is described along with experimental data. This facility is designed to study new linear acceleration techniques and new radiation sources based on linacs in combination with free electron lasers. The accelerator utilizes a photo-excited, metal cathode, radio frequency electron gun followed by two travelling wave accelerating sections and an Experimental Hall for the study program. (Author) 5 refs., 4 figs., tab

Operational experience with the CEBAF control system

International Nuclear Information System (INIS)

Hovater, C.; Chowdhary, M.; Karn, J.; Tiefenback, M.; Zeijts, J. van; Watson, W.

1996-01-01

The CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) successfully began its experimental nuclear physics program in November of 1995 and has since surpassed predicted machine availability. Part of this success can be attributed to using the EPICS (Experimental Physics and Industrial Control System) control system toolkit. The CEBAF control system is one of the largest accelerator control system now operating. It controls approximately 338 SRF cavities, 2,300 magnets, 500 beam position monitors and other accelerator devices, such as gun hardware and other beam monitoring devices. All told, the system must be able to access over 125,000 database records. The system has been well received by both operators and the hardware designers. The EPICS utilities have made the task of troubleshooting systems easier. The graphical and test-based creation tools have allowed operators to custom build control screens. In addition, the ability to integrate EPICS with other software packages, such as Tcl/Tk, has allowed physicists to quickly prototype high-level application programs, and to provide GUI front ends for command line driven tools. Specific examples of the control system applications are presented in the areas of energy and orbit control, cavity tuning and accelerator tune up diagnostics

77 FR 2120 - Environmental Impact Statement for New Orleans Rail Gateway (NORG), Jefferson and Orleans...

Science.gov (United States)

2012-01-13

... Xavier University of Louisiana, University Center, 3rd Floor, Mary and William McCaffrey Ballroom B, 4980..., Council Chambers, 1221 Elmwood Park Boulevard, Jefferson, LA 70123 Information on the meeting locations is... Press Drive and then continuing eastward along Dwyer Road; on the east along Maxent Canal near Bayou...

Implementation of a level 1 trigger system using high speed serial (VXS) techniques for the 12GeV high luminosity experimental programs at Thomas Jefferson National Accelerator Facility

International Nuclear Information System (INIS)

Cuevas, C.; Raydo, B.; Dong, H.; Gupta, A.; Barbosa, F.J.; Wilson, J.; Taylor, W.M.; Jastrzembski, E.; Abbott, D.

2009-01-01

We will demonstrate a hardware and firmware solution for a complete fully pipelined multi-crate trigger system that takes advantage of the elegant high speed VXS serial extensions for VME. This trigger system includes three sections starting with the front end crate trigger processor (CTP), a global Sub-System Processor (SSP) and a Trigger Supervisor that manages the timing, synchronization and front end event readout. Within a front end crate, trigger information is gathered from each 16 Channel, 12 bit Flash ADC module at 4 nS intervals via the VXS backplane, to a Crate Trigger Processor (CTP). Each Crate Trigger Processor receives these 500 MB/S VXS links from the 16 FADC-250 modules, aligns skewed data inherent of Aurora protocol, and performs real time crate level trigger algorithms. The algorithm results are encoded using a Reed-Solomon technique and transmission of this Level 1 trigger data is sent to the SSP using a multi-fiber link. The multi-fiber link achieves an aggregate trigger data transfer rate to the global trigger at 8 Gb/s. The SSP receives and decodes Reed-Solomon error correcting transmission from each crate, aligns the data, and performs the global level trigger algorithms. The entire trigger system is synchronous and operates at 250 MHz with the Trigger Supervisor managing not only the front end event readout, but also the distribution of the critical timing clocks, synchronization signals, and the global trigger signals to each front end readout crate. These signals are distributed to the front end crates on a separate fiber link and each crate is synchronized using a unique encoding scheme to guarantee that each front end crate is synchronous with a fixed latency, independent of the distance between each crate. The overall trigger signal latency is <3 uS, and the proposed 12GeV experiments at Jefferson Lab require up to 200KHz Level 1 trigger rate.

Jefferson Lab IR demo FEL photocathode quantum efficiency scanner

CERN Document Server

Gubeli, J; Grippo, A; Jordan, K; Shinn, M; Siggins, T

2001-01-01

Jefferson Laboratory's Free Electron Laser (FEL) incorporates a cesiated gallium arsenide (GaAs) DC photocathode gun as its electron source. By using a set of scanning mirrors, the surface of the GaAs wafer is illuminated with a 543.5nm helium-neon laser. Measuring the current flow across the biased photocathode generates a quantum efficiency (QE) map of the 1-in. diameter wafer surface. The resulting QE map provides a very detailed picture of the efficiency of the wafer surface. By generating a QE map in a matter of minutes, the photocathode scanner has proven to be an exceptional tool in quickly determining sensitivity and availability of the photocathode for operation.

The calculation, simulation, and measurement of longitudinal beam dynamics in electron injectors

International Nuclear Information System (INIS)

Dunham, B.; Liu, H.; Kazimi, R.

1997-01-01

Polarized electrons are a valuable commodity for nuclear physics research and every effort must be made to preserve them during transport Measurements of the beam emitted from the polarized source at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) have shown a considerable bunch lengthening with increasing beam current. This lengthening leads to unacceptable loss as the beam passes through the injector chopping system. We present an application of the longitudinal envelope equation to describe the bunch lengthening and compare the results to measurements and simulations using PARMELA. In addition, a possible solution to the problem by adding a low power buncher to the beamline is described and initial results are shown

Inverse free-electron laser accelerator development

International Nuclear Information System (INIS)

Fisher, A.; Gallardo, J.; Steenbergen, A. van; Sandweiss, J.; Fang, J.M.

1994-06-01

The study of the Inverse Free-Electron Laser, as a potential mode of electron acceleration, has been pursued at Brookhaven National Laboratory for a number of years. More recent studies focused on the development of a low energy (few GeV), high gradient, multistage linear accelerator. The authors are presently designing a short accelerator module which will make use of the 50 MeV linac beam and high power (2 x 10 11 W) CO 2 laser beam of the Accelerator Test Facility (ATF) at the Center for Accelerator Physics (CAP), Brookhaven National Laboratory. These elements will be used in conjunction with a fast excitation (300 μsec pulse duration) variable period wiggler, to carry out an accelerator demonstration stage experiment

Photoproduction of the f1(1285)/η(1295) Mesons using CLAS at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Dickson, Ryan [Carnegie Mellon Univ., Pittsburgh, PA (United States)

2011-07-18

This work presents the results of analysis of a meson mass m_x =1281.0 ± 0.8 MeV/ c² and a FWHM of Γ_x = 18.4 ± 1.4 MeV/ c² seen in CLAS at Jefferson Lab in photoproduction off the proton, γp → xp.

CLAS+FROST: new generation of photoproduction experiments at jefferson lab

International Nuclear Information System (INIS)

Pasyuk, E.

2009-01-01

A large part of the experimental program in Hall B of the Jefferson Lab is dedicated to baryon spectroscopy. Photoproduction experiments are essential part of this program. CEBAF Large Acceptance Spectrometer (CLAS) and availability of circularly and linearly polarized tagged photon beams provide unique conditions for this type of experiments. Recent addition of the Frozen Spin Target (FROST) gives a remarkable opportunity to measure double and triple polarization observables for different pseudo-scalar meson photoproduction processes. For the first time, a complete or nearly complete experiment becomes possible and will allow model independent extraction of the reaction amplitude. An overview of the experiment and its current status is presented. (author)

Cyclic platform dolomites and platform-to-basin transition of Jefferson Formation (Frasnian), southwest Montana and east-central Idaho

Energy Technology Data Exchange (ETDEWEB)

Dorobek, S.L.

1987-08-01

The Jefferson Formation (Frasnian) in southwestern Montana consists of cyclic sequences of shallow marine platformal dolomites that grade westward into slope/basinal facies in east-central Idaho. Regional sedimentologic characteristics of slope facies in Idaho indicate that the Jefferson platform resembled a distally steepened ramp. Slope facies consist of slope laminites with local small scale slumps and slope breccias. Shallow water platform-derived clasts are lacking in the slope breccias. Individual shallowing upward platform cycles are 25 m to < 1 m thick and consists of, in descending order: local solution-collapse breccia caps; cryptalgal dolomudstone; rare ooid dolograinstone; thin-bedded Amphipora dolowackestone; coarsely crystalline dolostones with abundant lenticular to domal stromatoporoids; and basal thin-bedded, fine-grained, shale dolostones with closely spaced hard-grounds that grade upward into burrow-homogenized, irregularly bedded dolostones.

Tiger Team Assessment of the Fermi National Accelerator Laboratory

International Nuclear Information System (INIS)

1992-06-01

This draft report documents the Tiger Team Assessment of the Fermi National Accelerator Laboratory (Fermilab) located in Batavia, Illinois. Fermilab is a program-dedicated national laboratory managed by the Universities Research Association, Inc. (URA) for the US Department of Energy (DOE). The Tiger Team Assessment was conducted from May 11 to June 8, 1992, under the auspices of DOE's Office of Special Projects (OSP) under the Office of the Assistant Secretary for Environment, Safety and Health (EH). The assessment was comprehensive, encompassing environmental, safety and health (ES ampersand H), and quality assurance (QA) disciplines; site remediation; facilities management; and waste management operations. Compliance with applicable Federal , State of Illinois, and local regulations; applicable DOE Orders; best management practices; and internal Fermilab requirements was addressed. In addition, an evaluation of the effectiveness of DOE and Fermilab management of the ES ampersand H/QA and self-assessment programs was conducted. The Fermilab Tiger Team Assessment is part a larger, comprehensive DOE Tiger Team Independent Assessment Program planned for DOE facilities. The objective of the initiative is to provide the Secretary of Energy with information on the compliance status of DOE facilities with regard to ES ampersand H requirements, root causes for noncompliance, adequacy of DOE and contractor ES ampersand H management programs, response actions to address the identified problem areas, and DOE-wide ES ampersand H compliance trends and root causes

The measurement of the optical cavity length for the infrared free electron laser

International Nuclear Information System (INIS)

Curtis, C.J.; Dahlberg, J.C.; Oren, W.A.; Tremblay, K.J.

1999-01-01

One of the final tasks involved in the alignment of the newly constructed Free Electron Laser at the Thomas Jefferson National Accelerator Facility was to accurately measure the length between two mirrors which make up the optical cavity. This presentation examines the survey techniques and equipment assembled in order to complete these measurements, together with the possible sources of error, and the accuracy achieved. (authors)

Technical meeting to 'Review of national programmes on fast reactors and accelerator driven systems (ADS)'. Working material

International Nuclear Information System (INIS)

2003-01-01

36th Annual Meeting of the Technical Working Group on Fast Reactors, the IAEA Technical Meeting (TM) on 'Review of National Programmes on Fast Reactors and Accelerator Driven Systems (ADS)', hosted by the Korean Atomic Energy Research Institute (KAERI) was attended by TWG-FR Members and Advisers from the following Member States (MS) and International Organizations: Brazil, France, Germany, India, Japan, the Republic of Kazakhstan, the Republic of Korea, the Russian Federation, the United Kingdom, the United States of America, and the OECD/NEA. The objectives of the meeting were to: 1) exchange information on the national programmes on Fast Reactors (FR) and Accelerator Driven Systems (ADS); 2) review the progress since the 35th TWG-FR Annual Meeting, including the status of the actions; 3) consider meeting arrangements for 2003 and 2004; 4) review the Agency's co-ordinated research activities in the field of FRs and ADS, as well as co-ordination of the TWG-FR's activities with other organizations. The participants made presentations on the status of the respective national programmes on FR and ADS development. A summary of the highlights for the period since the 35th TWG-FR Annual Meeting

An improved 8 GeV beam transport system for the Fermi National Accelerator Laboratory

International Nuclear Information System (INIS)

Syphers, M.J.

1987-06-01

A new 8 GeV beam transport system between the Booster and Main Ring synchrotrons at the Fermi National Accelerator Laboratory is presented. The system was developed in an effort to improve the transverse phase space area occupied by the proton beam upon injection into the Main Ring accelerator. Problems with the original system are described and general methods of beamline design are formulated. Errors in the transverse properties of a beamline at the injection point of the second synchrotron and their effects on the region in transverse phase space occupied by a beam of particles are discussed. Results from the commissioning phase of the project are presented as well as measurements of the degree of phase space dilution generated by the transfer of 8 GeV protons from the Booster synchrotron to the Main Ring synchrotron

Hadronic Multi-Particle Final State Measurements with CLAS at Jefferson Lab

International Nuclear Information System (INIS)

Will Brooks

2002-01-01

Precision measurements in the neutrino sector are becoming increasingly feasible due to the development of relatively high-rate experimental capabilities. These important developments command renewed attention to the systematic corrections needed to interpret the data. Hadronic multi-particle final state measurements made using CLAS at Jefferson Lab, together with a broad theoretical effort that links electro-nucleus and neutrino-nucleus data, will address this problem, and will elucidate long-standing problems in intermediate energy nuclear physics. This new work will ultimately enable precision determinations of fundamental quantities such as the neutrino mixing matrix elements in detailed studies of neutrino oscillations

Spectroscopic Study of L Hypernuclei with Electron Beams at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Satoshi [Tohoku Univ., Sendai (Japan); Gogami, Toshiyuki [Tohoku Univ., Sendai (Japan); Tang, Liguang [Hampton Univ., Hampton, VA (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2017-07-01

The missing mass spectroscopy of L hypernuclei with the (e, e'K^+) reaction was started from 2000 at Jefferson Lab. In this fifteen years, various hypernuclei (A = 7 - 52) including hyperon (L, S^0) productions have been studied with newly developed experimental techniques. The (e, e'K^+) reaction spectroscopy of L hypernuclei features its capability of absolute missing mass calibration and production of new species of hypernuclei which are the isospin partners of well studied hypernuclei by (K^-, pi-) and (pi^+, K^+) reactions. In this paper, we will review how we established the (e, e'K^+) spectroscopic study of hypernuclei.

High Gradient Accelerator Research

International Nuclear Information System (INIS)

Temkin, Richard

2016-01-01

The goal of the MIT program of research on high gradient acceleration is the development of advanced acceleration concepts that lead to a practical and affordable next generation linear collider at the TeV energy level. Other applications, which are more near-term, include accelerators for materials processing; medicine; defense; mining; security; and inspection. The specific goals of the MIT program are: • Pioneering theoretical research on advanced structures for high gradient acceleration, including photonic structures and metamaterial structures; evaluation of the wakefields in these advanced structures • Experimental research to demonstrate the properties of advanced structures both in low-power microwave cold test and high-power, high-gradient test at megawatt power levels • Experimental research on microwave breakdown at high gradient including studies of breakdown phenomena induced by RF electric fields and RF magnetic fields; development of new diagnostics of the breakdown process • Theoretical research on the physics and engineering features of RF vacuum breakdown • Maintaining and improving the Haimson / MIT 17 GHz accelerator, the highest frequency operational accelerator in the world, a unique facility for accelerator research • Providing the Haimson / MIT 17 GHz accelerator facility as a facility for outside users • Active participation in the US DOE program of High Gradient Collaboration, including joint work with SLAC and with Los Alamos National Laboratory; participation of MIT students in research at the national laboratories • Training the next generation of Ph. D. students in the field of accelerator physics.

76 FR 70110 - Foreign-Trade Zone 109-County of Jefferson, NY; Application for Reorganization and Expansion...

Science.gov (United States)

2011-11-10

... Coffeen Street, Watertown; and, Site 2 (16 acres)--Dexter Sulphite Mill, 349 Lakeview Dr. & Stockton Avenue, Dexter. The grantee's proposed service area under the ASF would be the County of Jefferson, New..., NYS Route 12F, 22529 Airport Drive, Dexter. The ASF allows for the possible exemption of one magnet...

Accelerator shielding benchmark problems

International Nuclear Information System (INIS)

Hirayama, H.; Ban, S.; Nakamura, T.

1993-01-01

Accelerator shielding benchmark problems prepared by Working Group of Accelerator Shielding in the Research Committee on Radiation Behavior in the Atomic Energy Society of Japan were compiled by Radiation Safety Control Center of National Laboratory for High Energy Physics. Twenty-five accelerator shielding benchmark problems are presented for evaluating the calculational algorithm, the accuracy of computer codes and the nuclear data used in codes. (author)

Timber resource statistics for all forest land, except national forests, in eastern Oregon.

Science.gov (United States)

Donald R. Gedney; Patricia M. Bassett; Mary A. Mei

1989-01-01

This report summarizes a 1987 timber resource inventory of all forest land, except National Forests, in the 17 counties (Baker, Crook, Deschutes, Gilliam, Grant, Harney, Jefferson, Klamath, Lake, Malheur, Morrow, Sherman, Umatilla, Union, Wallowa, Wasco, and Wheeler Counties) in eastern Oregon. Detailed tables of forest area, timber volume, growth, mortality, and...

Hospital Web site 'tops' in Louisiana. Hospital PR, marketing group cites East Jefferson General Hospital.

Science.gov (United States)

Rees, Tom

2002-01-01

East Jefferson General Hospital in Metairie, La., launched a new Web site in October 2001. Its user-friendly home page offers links to hospital services, medical staff, and employer information. Its jobline is a powerful tool for recruitment. The site was awarded the 2002 Pelican Award for Best Consumer Web site by the Louisiana Society for Hospital Public Relations & Marketing.

The Electric Form Factor of the Neutron via Recoil Polarimetry to Q2 1.47 (GeV/c)2

International Nuclear Information System (INIS)

Bradley Plaster; Richard Madey; Andrei Semenov; Simon Taylor; Aram Aghalaryan; Erick Crouse; Glen MacLachlan; Shigeyuki Tajima; William Tireman; Chenyu Yan; Abdellah Ahmidouch; Brian Anderson; Hartmuth Arenhovel; Razmik Asaturyan; O. Baker; Alan Baldwin; Paul Brewer; Roger Carlini; Michael Christy; Steve Churchwell; Leon Cole; Samuel Danagoulian; Donal Day; Mostafa Elaasar; Rolf Ent; Manouchehr Farkhondeh; Howard Fenker; John Finn; Liping Gan; Kenneth Garrow; Calvin Howell; Paul Gueye; Bitao Hu; Mark Jones; James Kelly; Cynthia Keppel; Mahbubul Khandaker; Wooyoung Kim; Stanley Kowalski; Allison Lung; David Mack; D. Manley; Pete Markowitz; Tilmann Reichelt; Joerg Reinhold; Julie Roche; Yoshinori Sato; Irina Semenova; Wonick Seo; Neven Simicevic; Gregory Smith; Samuel Stepanyan; Vardan Tadevosyan; Liguang Tang; Paul Ulmer; William Vulcan; John Watson; Steven Wells; Frank Wesselmann; Stephen Wood; Chen Yan; Seunghoon Yang; Lulin Yuan; Wei-Ming Zhang; Hong Guo Zhu; Xiaofeng Zhu

2003-01-01

The Jefferson Laboratory E93-038 collaboration conducted measurements of the ratio of the electric form factor to the magnetic form factor of the neutron, G n E/G n M, via recoil polarimetry from the quasielastic 2 H((rvec e),e/(rvec n)) 1 H reaction at three values of Q 2 [viz., 0.45, 1.15, and 1.47 (GeV/c) 2 ] in Hall C of the Thomas Jefferson National Accelerator Facility. The preliminary results for G n E at Q 2 = 0.45 and 1.15 (GeV/c) 2 are consistent with the Galster parameterization; however, the preliminary result for G n E at Q 2 = 1.47 (GeV/c) 2 lies slightly above the Galster parameterization

Superconducting magnets technologies for large accelerator

International Nuclear Information System (INIS)

Ogitsu, Toru

2017-01-01

The first hadron collider with superconducting magnet technologies was built at Fermi National Accelerator Laboratory as TEVATRON. Since then, the superconducting magnet technologies are widely used in large accelerator applications. The paper summarizes the superconducting magnet technologies used for large accelerators. (author)

Analysis of Deeply Virtual Compton Scattering data at Jefferson Lab and proton tomography

Energy Technology Data Exchange (ETDEWEB)

Dupre, R.; Guidal, M.; Niccolai, S. [Institut de Physique Nucleaire d' Orsay, CNRS-IN2P3, Universite Paris-Sud, Universite Paris-Saclay, Orsay (France); Vanderhaeghen, M. [Johannes Gutenberg-Universitaet, Institut fuer Kernphysik und PRISMA Cluster of Excellence, Mainz (Germany)

2017-08-15

The CLAS and Hall A Collaborations at Jefferson Laboratory have recently released new results for the ep → epγ reaction. We analyze these new data within the Generalized Parton Distribution formalism. Employing a fitter algorithm introduced and used in earlier works, we are able to extract from these data new constraints on the kinematical dependence of three Compton Form Factors. Based on experimental data, we subsequently extract the dependence of the proton charge radius on the quarks' longitudinal momentum fraction. (orig.)

Jefferson Lab mass storage and file replication services

International Nuclear Information System (INIS)

Bird, I.; Chen, Y.; Hess, B.; Kowalski, A.; Watson, C.

2001-01-01

Jefferson Lab has implemented a scalable, distributed, high performance mass storage system-JASMine. The system is entirely implemented in Java, provides access to robotic tape storage and includes disk cache and stage manager components. The disk manager subsystem may be used independently to manage stand-alone disk pools. The system includes a scheduler to provide policy-based access to the storage systems. Security is provided by pluggable authentication modules and it implemented at the network socket level. The tape and disk cache systems have well defined interfaces in order to provide integration with grid-based services. The system is in production and being used to archive 1 TB per day from the experiments, and currently moves over 2 TB per day total. The authors will describe the architecture of JASMine; discuss the rationale for building the system, and present a transparent 3 rd party file replication service to move data to collaborating institutes using JASMine, XML, and servlet technology interfacing to grid-based file transfer mechanisms

Deeply Virtual Compton Scattering Studies at Jefferson Lab

International Nuclear Information System (INIS)

Sabatie, F.

2010-11-01

This document describes the early experimental effort at Jefferson Lab to unravel the Generalized Parton Distributions (GPD), using the Deeply Virtual Compton Scattering (DVCS) process. The GPDs contain the usual form factors and parton distribution functions, but in addition, they include correlations between states of different longitudinal and transverse momenta. They therefore give access to a three-dimensional picture of the nucleon. DVCS is the cleanest process allowing to extract GPDs, and as early as 2000, a number of experiments were proposed for this purpose. The results of the first exploratory experiments are presented as well as the first measurements of linear combinations of GPDs. In addition, a thorough discussion on the insights gained from these early experiments is proposed, linked with the theoretical tools used to extract GPDs from DVCS data. Finally, improvements on what was done for this first experimental phase are proposed and discussed, and new proposals and measurements are described. (author)

Environmental Survey preliminary report, Fermi National Accelerator Laboratory, Batavia, Illinois

International Nuclear Information System (INIS)

1988-10-01

This report presents the preliminary findings from the first phase of the Environmental Survey of the US Department of Energy (DOE) Fermi National Accelerator Laboratory (Fermilab), conducted September 14 through 25, 1987. The Survey is being conducted by an interdisciplinary team of environmental specialists led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Individual participants for the Survey team are being supplied by a private contractor. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with Fermilab. The Survey covers all environmental media and all areas of environmental regulation. It is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations performed at Fermilab, and interviews with site personnel. 110 refs., 26 figs., 41 tabs

Environmental Survey preliminary report, Fermi National Accelerator Laboratory, Batavia, Illinois

Energy Technology Data Exchange (ETDEWEB)

1988-10-01

This report presents the preliminary findings from the first phase of the Environmental Survey of the US Department of Energy (DOE) Fermi National Accelerator Laboratory (Fermilab), conducted September 14 through 25, 1987. The Survey is being conducted by an interdisciplinary team of environmental specialists led and managed by the Office of Environment, Safety and Health's Office of Environmental Audit. Individual participants for the Survey team are being supplied by a private contractor. The objective of the Survey is to identify environmental problems and areas of environmental risk associated with Fermilab. The Survey covers all environmental media and all areas of environmental regulation. It is being performed in accordance with the DOE Environmental Survey Manual. This phase of the Survey involves the review of existing site environmental data, observations of the operations performed at Fermilab, and interviews with site personnel. 110 refs., 26 figs., 41 tabs.

HOM Survey of the First CEBAF Upgrade Style Cavity Pair

International Nuclear Information System (INIS)

Marhauser, Frank; Daly, Edward; Davis, G.; Drury, Michael; Grenoble, Christiana; Hogan, John; Manus, Robert; Preble, Joseph; Reece, Charles; Rimmer, Robert; Tian, Kai; Wang, Haipeng

2009-01-01

The planned upgrade of the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Laboratory (JLab) requires ten new superconducting rf (SRF) cavity cryomodules to double the beam energy to the envisaged 12 GeV. Adequate cavity Higher Order Mode (HOM) suppression is essential to avoid multipass, multibunch beam break-up (BBU) instabilities of the recirculating beam. We report on detailed HOM surveys performed for the first two upgrade style cavities tested in a dedicated cavity pair cryomodule at 2K. The safety margin to the BBU threshold budget at 12 GeV has been assessed.

Mega-electron-volt ultrafast electron diffraction at SLAC National Accelerator Laboratory

Energy Technology Data Exchange (ETDEWEB)

Weathersby, S. P.; Brown, G.; Chase, T. F.; Coffee, R.; Corbett, J.; Eichner, J. P.; Frisch, J. C.; Fry, A. R.; Gühr, M.; Hartmann, N.; Hast, C.; Hettel, R.; Jobe, R. K.; Jongewaard, E. N.; Lewandowski, J. R.; Li, R. K., E-mail: lrk@slac.stanford.edu; Lindenberg, A. M.; Makasyuk, I.; May, J. E.; McCormick, D. [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025 (United States); and others

2015-07-15

Ultrafast electron probes are powerful tools, complementary to x-ray free-electron lasers, used to study structural dynamics in material, chemical, and biological sciences. High brightness, relativistic electron beams with femtosecond pulse duration can resolve details of the dynamic processes on atomic time and length scales. SLAC National Accelerator Laboratory recently launched the Ultrafast Electron Diffraction (UED) and microscopy Initiative aiming at developing the next generation ultrafast electron scattering instruments. As the first stage of the Initiative, a mega-electron-volt (MeV) UED system has been constructed and commissioned to serve ultrafast science experiments and instrumentation development. The system operates at 120-Hz repetition rate with outstanding performance. In this paper, we report on the SLAC MeV UED system and its performance, including the reciprocal space resolution, temporal resolution, and machine stability.

Annual Site Environmental Report: 2015 (ASER) for the SLAC National Accelerator Laboratory

Energy Technology Data Exchange (ETDEWEB)

Sabba, Dellilah [SLAC National Accelerator Lab., Menlo Park, CA (United States)

2016-09-01

This report, prepared by the SLAC National Accelerator Laboratory (SLAC) for the U.S. Department of Energy (DOE), SLAC Site Office (SSO), provides a comprehensive summary of the environmental program activities at SLAC for calendar year 2015. Annual Site Environmental Reports (ASERs) are prepared for all DOE sites with significant environmental activities, and distributed to relevant external regulatory agencies and other interested organizations or individuals. To the best of my knowledge, this report accurately summarizes the results of the 2015 environmental monitoring, compliance, and restoration programs at SLAC. This assurance can be made based on SSO and SLAC review of the ASER, and quality assurance protocols applied to monitoring and data analyses at SLAC.

Accelerator and Electrodynamics Capability Review

International Nuclear Information System (INIS)

Jones, Kevin W.

2010-01-01

Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

Accelerator and electrodynamics capability review

Energy Technology Data Exchange (ETDEWEB)

Jones, Kevin W [Los Alamos National Laboratory

2010-01-01

Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

Aerial gamma ray and magnetic survey, Jefferson City Quadrangle, Missouri. Final report

International Nuclear Information System (INIS)

1980-11-01

The Jefferson City quadrangle covers approximately 7500 square miles at the Northwestern end of the Ozark uplift. Lithified material exposed, ranges in age from Cambrian through Pennsylvanian, but Pennsylvanian sediments dominate the surface as mapped. Some alluvium is mapped in river flood plain areas. A search of available literature revealed no known uranium deposits. A total of 95 uranium anomalies were detected and are discussed briefly in this report. All anomalies are related to cultural features, but those associated with coal mine tailings appear to have some significance. Magnetic data appear to relate to complexities in the underlying Precambrian rocks

A RICH detector for strangeness physics in Hall A at Jefferson Lab

International Nuclear Information System (INIS)

Cusanno, F.; Garibaldi, F.; Cisbani, E.; Colilli, S.; De Cataldo, G.; De Leo, R.; Giuliani, F.; Gricia, M.; Lagamba, L.; Lucentini, M.; Reitz, B.; Santavenere, F.; Urciuoli, G.M.

2004-01-01

The high-resolution hypernuclear spectroscopy experiment at Jefferson Lab, Hall A (E94-107), needs unambiguous kaon identification. Due to the huge pion and proton background, the standard Hall A hadron particle identification, based on a time of flight and two aerogel threshold Cherenkov detectors, is not sufficient. For this task a proximity focusing C 6 F 14 /CsI RICH has been built. Recently, after some improvements to the mechanical structure of its wire chamber and to its electronics rate capability, the RICH has been tested with cosmic rays. This paper represents a status report of the RICH detector

Design and implementation of a slow orbit control package at Thomas Jefferson National Accelerator Facility

International Nuclear Information System (INIS)

Zeijts, J. van; Witherspoon, S.; Watson, W.A.

1997-01-01

The authors describe the design and implementation of a C++ client/server based slow orbit and energy control package based on the CDEV software control bus. Several client applications are described and operational experience is given

Plasma-based and novel accelerators

International Nuclear Information System (INIS)

Sugihara, Ryo; Nishida, Yasushi

1992-05-01

This publication is a collection of papers presented at Workshop on Plasma-Based and Novel Accelerators held at National Institute for Fusion Science, Nagoya, on December 19-20, 1991. Plasma-based accelerators are attracting considerable attention in these days a new, exciting field of plasma applications. The study gives rise to and spurs study of other unique accelerators like laser-based accelerators. The talks in the Workshop encompassed beat-wave accelerator (BWA), plasma wake field accelerator (PWFA), V p x B accelerator, laser-based accelerators and some novel methods of acceleration. They also covered the topics such as FEL, cluster acceleration and plasma lens. Small scale experiments as those in universities have exhibited brilliant results while larger scale experiments like BWA in Institute of Laser Engineering, Osaka University, and PWFA in KEK start showing significant results as well. (J.P.N.)

Deeply virtual Compton scattering at Jefferson Laboratory

Energy Technology Data Exchange (ETDEWEB)

Biselli, Angela S. [Fairfield University - Department of Physics 1073 North Benson Road, Fairfield, CT 06430, USA; Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2016-08-01

The generalized parton distributions (GPDs) have emerged as a universal tool to describe hadrons in terms of their elementary constituents, the quarks and the gluons. Deeply virtual Compton scattering (DVCS) on a proton or neutron ($N$), $e N \\rightarrow e' N' \\gamma$, is the process more directly interpretable in terms of GPDs. The amplitudes of DVCS and Bethe-Heitler, the process where a photon is emitted by either the incident or scattered electron, can be accessed via cross-section measurements or exploiting their interference which gives rise to spin asymmetries. Spin asymmetries, cross sections and cross-section differences can be connected to different combinations of the four leading-twist GPDs (${H}$, ${E}$, ${\\tilde{H}}$, ${\\tilde{E}}$) for each quark flavors, depending on the observable and on the type of target. This paper gives an overview of recent experimental results obtained for DVCS at Jefferson Laboratory in the halls A and B. Several experiments have been done extracting DVCS observables over large kinematics regions. Multiple measurements with overlapping kinematic regions allow to perform a quasi-model independent extraction of the Compton form factors, which are GPDs integrals, revealing a 3D image of the nucleon.

JLABGEO: a new survey and alignment data manager

Energy Technology Data Exchange (ETDEWEB)

Tremblay, K.J.; Curtis, C.J. [Thomas Jefferson National Accelerator Facility, Virginia (United States)

1999-07-01

The Survey and Alignment group at Thomas Jefferson National Accelerator Facility has relied upon the MS-Dos program Geonet, originally developed at Stanford Linear Accelerator, as its central data manager. With the Lab decision to only use Microsoft Windows NT as the platform for PCs, limitations were reached in using Geonet. A program has been developed at Jefferson Lab, JLabGeo to mimic as many of the Geonet functions as possible, while also expanding and enhancing its capabilities. All of the adjustment programs, originally developed by Dr. Ingolf Burstedde, have been revised in order to work with arrays of any size, and operate as console applications in the NT environment. Integrating the use of a central file server as both the source of the executable programs and data files also ensures that all workstations are using the most recent data. Work continues on developing JLabGeo, notably the integration of all of our survey data types into a easily retrievable database, and the development of a central repository for beamline information and ideal coordinates. (authors)

JLABGEO: a new survey and alignment data manager

International Nuclear Information System (INIS)

Tremblay, K.J.; Curtis, C.J.

1999-01-01

The Survey and Alignment group at Thomas Jefferson National Accelerator Facility has relied upon the MS-Dos program Geonet, originally developed at Stanford Linear Accelerator, as its central data manager. With the Lab decision to only use Microsoft Windows NT as the platform for PCs, limitations were reached in using Geonet. A program has been developed at Jefferson Lab, JLabGeo to mimic as many of the Geonet functions as possible, while also expanding and enhancing its capabilities. All of the adjustment programs, originally developed by Dr. Ingolf Burstedde, have been revised in order to work with arrays of any size, and operate as console applications in the NT environment. Integrating the use of a central file server as both the source of the executable programs and data files also ensures that all workstations are using the most recent data. Work continues on developing JLabGeo, notably the integration of all of our survey data types into a easily retrievable database, and the development of a central repository for beamline information and ideal coordinates. (authors)

High energy angular distribution measurements of the exclusive deuteron photodisintegration reaction

International Nuclear Information System (INIS)

Schulte, E. C.; A. Afanasev; M. Amarian; K. Aniol; S. Becher; K. Benslama; L. Bimbot; P. Bosted; E. Brash; J. Calarco; Z. Chai; C. Chang; T. Chang; J. P. Chen; S. Choi; E. Chudakov; S. Churchwell; D. Crovelli; S. Dieterich; S. Dumalski; D. Dutta; M. Epstein; K. Fissum; B. Fox; S. Frullani; H. Gao; J. Gao; F. Garibaldi; O. Gayou; R. Gilman; A. Glamazdin; C. Glashausser; J. Gomez; V. Gorbenko; J.-O. Hansen; R. J. Holt; J. Hovdebo; G. M. Huber; C. W. de Jager; X. Jiang; C. Jones; M. K. Jones; J. Kelly; E. Kinney; E. Kooijman; G. Kumbartzki; M. Kuss; J. LeRose; M. Liang; R. Lindgren; N. Liyanage; S. Malov; D. Margaziotis; P. Markowitz; K. McCormick; D. Meekins; Z.-E. Meziani; R. Michaels; J. Mitchell; L. Morand; C. Perdrisat; R. Pomatsalyuk; V. Punjabi; A. Radyushkin; R. Ransome; R. Roche; M. Rvachev; A. Saha; A. Sarty; D. Simon; S. Strauch; R. Suleiman; L. Todor; P. Ulmer; G. M. Urciuoli; K. Wijesooriya; B. Wojtsekhowski; F. Xiong; W. Xu

2002-01-01

The first complete measurements of the angular distributions of the two-body deuteron photodisintegration differential cross section at photon energies above 1.6 GeV were performed at the Thomas Jefferson National Accelerator Facility. The results show a persistent forward-backward asymmetry up to Egamma = 2.4 GeV, the highest-energy measured in this experiment. The Hard Rescattering and the Quark-Gluon string models are in fair agreement with the results

Study of CSR Effects in the Jefferson Laboratory FEL Driver

Energy Technology Data Exchange (ETDEWEB)

Hall, C. C. [Colorado State U.; Biedron, S. [Colorado State U.; Burleson, Theodore A. [Colorado State U.; Milton, Stephen V. [Colorado State U.; Morin, Auralee L. [Colorado State U.; Benson, Stephen V. [JLAB; Douglas, David R. [JLAB; Evtushenko, Pavel E. [JLAB; Hannon, Fay E. [JLAB; Li, Rui [JLAB; Tennant, Christopher D. [JLAB; Zhang, Shukui [JLAB; Carlsten, Bruce E. [LANL; Lewellen, John W. [LANL

2013-08-01

In a recent experiment conducted on the Jefferson Laboratory IR FEL driver the effects of Coherent Synchrotron Radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR chicane. This experiment also provides a valuable opportunity to benchmark existing CSR models in a system that may not be fully represented by a 1-D CSR model. Here we present results from this experiment and compare to initial simulations of CSR in the magnetic compression chicane of the machine. Finally, we touch upon the possibility for CSR induced microbunching gain in the magnetic compression chicane, and show that parameters in the machine are such that it should be thoroughly damped.

SANE Of Jefferson Lab: Spin Asymmetries on the Nucleon Experiment

International Nuclear Information System (INIS)

Ahmidouch, Abdellah

2011-01-01

The Spin Asymmetry on the Nucleon Experiment (SANE) at Jefferson Lab measures proton spin observables A 1 p , A 2 p and structure functions g 1 p and g 2 p over a broad range of Bjorken scaling variable x from 0.3 to 0.8, for four-momentum transfers ranging from 2.5 GeV 2 to 6.5 GeV 2 . Inclusive double spin asymmetries were measured by scattering 4.7 and 5.9-GeV longitudinally polarized electron beam off a polarized solid NH 3 target, in both parallel and near-perpendicular configuration. Scattered electrons were detected using a novel non-magnetic detector array with 194-msr acceptance. This paper presents the physics motivation for the experiment, the detector performance, and the latest status of the ongoing data analysis.

Laser-plasma accelerators, acceleration of particles through laser-matter interaction at ultra-high intensity

International Nuclear Information System (INIS)

Lefebvre, E.

2010-01-01

This series of slides overviews the development of powerful lasers for inertial confinement fusion (Icf) at NIF (National Ignition Facility, Usa) and LMJ (Laser Megajoule, France) facilities. Then the principle of laser wakefield acceleration is presented and the possibility of designing compact accelerators delivering 200 GeV/m while conventional RF accelerators reach only 50 MeV/m, is considered. This technical breakthrough will bring important gains in terms of size, cost and new uses for accelerators. While Icf will use nanosecond (10 -9 s) laser pulses, wakefield accelerators will use femtosecond (10 -15 s) laser pulses which means more power but less energy. The electrons accelerated by laser can produce a multi-MeV X radiation useful for industrial radiography or cancer treatment. (A.C.)

An emittance measurement system for a wide range of bunch charges

International Nuclear Information System (INIS)

Dunham, B.; Engwall, D.; Hofler, A.; Keesee, M.; Legg, R.

1997-01-01

As a part of the emittance measurements planned for the FEL injector at the Thomas Jefferson National Accelerator Facility (Jefferson Lab), the authors have developed an emittance measurement system that covers the wide dynamic range of bunch charges necessary to fully characterize the high-DC-voltage photocathode gun. The measurements are carried out with a variant of the classical two-slit method using a slit to sample the beam in conjunction with a wire scanner to measure the transmitted beam profile. The use of commercial, ultra-low noise picoammeters makes it possible to cover the wide range of desired bunch charges, with the actual measurements made over the range of 0.25 pC to 125 pC. The entire system, including its integration into the EPICS control system, is discussed

SHMS Hodoscopes and Time of Flight System

Science.gov (United States)

Craycraft, Kayla; Malace, Simona

2017-09-01

As part of the Thomas Jefferson National Accelerator Facility's (Jefferson Lab) upgrade from 6 GeV to 12 GeV, a new magnetic focusing spectrometer, the Super High Momentum Spectrometer (SHMS), was installed in experimental Hall C. The detector stack consists of horizontal drift chambers for tracking, gas Cerenkov and Aerogel detectors and a lead glass calorimeter for particle identification. A hodoscope system consisting of three planes of scintillator detectors (constructed by James Madison University) and one plane of quartz bars (built by North Carolina A&T State University) is used for triggering and time of flight measurements. This presentation consists of discussion of the installation, calibration, and characterization of the detectors used in this Time of Flight system. James Madison University, North Carolina A&T State University.

Brazing techniques for side-coupled electron accelerator structures

International Nuclear Information System (INIS)

Hansborough, L.D.; Clark, W.L.; DePaula, R.A.; Martinez, F.A.; Roybal, P.L.; Wilkerson, L.C.; Young, L.M.

1986-01-01

The collaboration between the Los Alamos National Laboratory and the National Bureau of Standards (NBS), started in 1979, has led to the development of an advanced c-w microtron accelerator design. The four 2380-MHz NBS accelerating structures, containing a total of 184 accelerating cavities, have been fabricated and delivered. New fabrication methods, coupled with refinements of hydrogen-furnace brazing techniques described in this paper, allow efficient production of side-coupled structures. Success with the NBS RTM led to Los Alamos efforts on similar 2450-MHz accelerators for the microtron accelerator operated by the Nuclear Physics Department of the University of Illinois. Two accelerators (each with 17 cavities) have been fabricated; in 1986, a 45-cavity accelerator is being fabricated by private industry with some assistance from Los Alamos. Further private industry experience and refinement of the described fabrication techniques may allow future accelerators of this type to be completely fabricated by private industry

DarkLight: A Search for Dark Forces at the Jefferson Laboratory Free-Electron Laser Facility

Energy Technology Data Exchange (ETDEWEB)

Balewski, Jan; Bernauer, J; Bertozzi, William; Bessuille, Jason; Buck, B; Cowan, Ray; Dow, K; Epstein, C; Fisher, Peter; Gilad, Shalev; Ihloff, Ernest; Kahn, Yonatan; Kelleher, Aidan; Kelsey, J; Milner, Richard; Moran, C; Ou, Longwu; Russell, R; Schmookler, Barak; Thaler, J; Tschalar, C; Vidal, Christopher; Winnebeck, A; Benson, Stephen [JLAB; Gould, Christopher [JLAB; Biallas, George [JLAB; Boyce, James [JLAB; Coleman, James [JLAB; Douglas, David [JLAB; Ent, Rolf [JLAB; Evtushenko, Pavel [JLAB; Fenker, Howard [JLAB; Gubeli, Joseph [JLAB; Hannon, Fay [JLAB; Huang, Jia [JLAB; Jordan, Kevin [JLAB; Legg, Robert [JLAB; Marchlik, Matthew [JLAB; Moore, Steven [JLAB; Neil, George [JLAB; Shinn, Michelle D [JLAB; Tennant, Christopher [JLAB; Walker, Richard [JLAB; Williams, Gwyn [JLAB; Zhang, Shukui [JLAB; Freytsis, M; Fiorito, Ralph; O' Shea, P; Alarcon, Ricardo; Dipert, R; Ovanesyan, G; Gunter, Thoth; Kalantarians, Narbe; Kohl, M; Albayrak, Ibrahim; Horn, Tanja; Gunarathne, D S; Martoff, C J; Olvitt, D L; Surrow, Bernd; Lia, X; Beck, Reinhard; Schmitz, R; Walther, D; Brinkmann, K; Zaunig, H

2014-05-01

We give a short overview of the DarkLight detector concept which is designed to search for a heavy photon A' with a mass in the range 10 MeV/c^2 < m(A') < 90 MeV/c^2 and which decays to lepton pairs. We describe the intended operating environment, the Jefferson Laboratory free electon laser, and a way to extend DarkLight's reach using A' --> invisible decays.

Pseudospread of the atlas: false sign of Jefferson fracture in young children

International Nuclear Information System (INIS)

Suss, R.A.; Zimmerman, R.D.; Leeds, N.E.

1983-01-01

Jefferson fractures are rare prior to teen-age. Three young children examined after trauma exhibited the characteristic spread appearance of the atlas, but fractures were excluded radiographically and clinically. A retrospective study demonstrated a similar appearance, termed pseudospread, in most children aged 3 months to 4 years, including over 90% during the second year. Pseudospread results from a discrepancy between the neural growth pattern of the atlas and the somatic pattern of the axis. An atlas spread index is defined and a normal range presented. When an atlas fracture is suggested by apparent lateral spread of the lateral atlas masses, computed tomography is useful to demonstrate an intact atlas ring

Workshop Engages PCs in Accelerator Controls

International Nuclear Information System (INIS)

Matthew Bickley

2006-01-01

To discuss the rapidly growing and changing use of personal computers (PCs) in accelerator control systems, 80 accelerator controls specialists from 26 institutions in North America, Europe and Asia attended the 6. International Workshop on Personal Computers and Particle Accelerator Controls, PCaPAC2006, held October 24-27 at Jefferson Lab in Newport News, Virginia. PCs have become increasingly applicable to the control of accelerators as their computing capacities have increased exponentially over the last 10 years. Capabilities that once required the power available only from expensive, small-market systems offered by DEC, Sun or IBM can now be obtained with commodity hardware offered by many vendors. The price/performance ratio presented by any standard PC makes a compelling case for using PC hardware in accelerator controls wherever possible. The PCaPAC meeting underscored the importance of collaborative control system development. Several talks focused on additions to three such systems, TINE, TANGO and EPICS. The diverse contributions to these toolkits, both in content and source, demonstrate the power of leveraged software development across a number of facilities. TINE originated in DESY's desire to give users a unified software bus above disparate underlying platforms. TINE discussions at PCaPAC centered on the toolkit's interface layers, including address redirection and integration with other control systems. TANGO has been a collaborative effort from its inception. Based on CORBA, this open-source controls toolkit is a registered project in the source forge system. The workshop TANGO presentation discussed contributions from four TANGO institutions, and mentioned a broad range of new tools, from user interface applications to code generators and database integration software. EPICS, which was started at LANL in the 1980s, includes contributions from dozens of institutions around the world. EPICS-related PCaPAC discussions included virtual machines at

Hadron accelerators in medicine

International Nuclear Information System (INIS)

Amaldi, U.

1996-01-01

The application of hadron accelerators (protons and light ions) in cancer therapy is discussed. After a brief introduction on the rationale for the use of heavy charged particles in radiation therapy, a discussion is given on accelerator technology and beam delivery systems. Next, existing and planned facilities are briefly reviewed. The Italian Hadron-therapy Project is then described in some detail, with reference ro both the National Centre for Oncological Hadron-therapy and the design of different types of compact proton accelerators aimed at introducing proton therapy in a large umber of hospitals. (author)

Sao Paulo pelletron accelerator: fortieth anniversary

International Nuclear Information System (INIS)

Pereira, Dirceu

2012-01-01

Full text: This year the 8MV Sao Paulo Pelletron tandem accelerator completes 40 years . This electrostatic accelerator was installed in the Sao Paulo University in 1972 , and it was the first of this model constructed the National Electrostatic Corporation with several innovations particularly with respect to the new concept of accelerator tube and the charge system. In the talk will be discussed the performance of the accelerator during all these years and the main result scientific results. (author)

Sao Paulo pelletron accelerator: fortieth anniversary

Energy Technology Data Exchange (ETDEWEB)

Pereira, Dirceu [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica

2012-07-01

Full text: This year the 8MV Sao Paulo Pelletron tandem accelerator completes 40 years . This electrostatic accelerator was installed in the Sao Paulo University in 1972 , and it was the first of this model constructed the National Electrostatic Corporation with several innovations particularly with respect to the new concept of accelerator tube and the charge system. In the talk will be discussed the performance of the accelerator during all these years and the main result scientific results. (author)

LINAC for ADS application - accelerator technologies

International Nuclear Information System (INIS)

Garnett, Robert W.; Sheffreld, Richard L.

2009-01-01

Sifnificant high-current, high-intensity accelerator research and development have been done in the recent past in the US, centered primarily at Los Alamos National Laboratory. These efforts have included designs for the Accelerator Production of Tritium Project, Accelerator Transmutation of Waste, and Accelerator Driven Systems, as well as many others. This past work and some specific design principles that were developed to optimie linac designs for ADS and other high-intensity applications will be discussed briefly.

High resolution hypernuclear spectroscopy at Jefferson Lab Hall A

International Nuclear Information System (INIS)

Garibaldi, F.; Bydžovský, P.; Cisbani, E.; Cusanno, F.; De Leo, R.; Frullani, S.; Iodice, M.; LeRose, J.J.; Markowitz, P.; Millener, D.J.; Urciuoli, G.M.

2013-01-01

The characteristics of the Jefferson Lab electron beam, together with those of the experimental equipment, offer a unique opportunity to study hypernuclear spectroscopy via electromagnetic induced (e,e ′ K + ) reactions. Experiment 94-107 started a systematic study on 1p-shell targets, 12 C, 9 Be and 16 O. For 12 C for the first time measurable strength in the core-excited part of the spectrum between the ground state and the p state was shown in the 12 Λ B spectrum. For 16 O a high-quality 16 Λ N spectrum was produced for the first time with sub-MeV energy resolution. A very precise Λ binding energy value for 16 Λ N, calibrated against the elementary (e,e ′ K + ) reaction on hydrogen, has also been obtained. Preliminary data on the 9 Λ Li spectrum shows some disagreement in strength for the second and third doublet with respect to the theory

Multipactor Physics, Acceleration, and Breakdown in Dielectric-Loaded Accelerating Structures

International Nuclear Information System (INIS)

Fischer, Richard P.; Gold, Steven H.

2016-01-01

The objective of this 3-year program is to study the physics issues associated with rf acceleration in dielectric-loaded accelerating (DLA) structures, with a focus on the key issue of multipactor loading, which has been found to cause very significant rf power loss in DLA structures whenever the rf pulsewidth exceeds the multipactor risetime (~10 ns). The experiments are carried out in the X-band magnicon laboratory at the Naval Research Laboratory (NRL) in collaboration with Argonne National Laboratory (ANL) and Euclid Techlabs LLC, who develop the test structures with support from the DoE SBIR program. There are two main elements in the research program: (1) high-power tests of DLA structures using the magnicon output (20 MW @11.4 GHz), and (2) tests of electron acceleration in DLA structures using relativistic electrons from a compact X-band accelerator. The work during this period has focused on a study of the use of an axial magnetic field to suppress multipactor in DLA structures, with several new high power tests carried out at NRL, and on preparation of the accelerator for the electron acceleration experiments.

A System for Managing Critical Knowledge for Accelerator Subsystems: Pansophy

International Nuclear Information System (INIS)

C. Reece; V. Bookwalter; B. Madre

2001-01-01

Accelerator development and construction projects often intentionally push the envelope of well-established technical performance and manageable complexity. In addition, the desire for efficient retention and exploitation of accumulated experience across the multi-decade life cycles of major installations calls for a robust, yet user-friendly knowledge management system. To meet these needs, we are presently deploying a new web-based system at Jefferson Lab: Pansophy. This system is a custom integration of several commercial software utilities, DocushareTM, ColdFusionTM, MatlabTM, IngresTM, and common desktop programs. Users of the system range from process managers, shop-floor technicians, test engineers, to after-the-fact data miners and operations staff. The system integrates important QA elements of procedural control, automated data accumulation into a secured central database, prompt and reliable data query and retrieval, and online analysis tools, all accessed by the user via their platform-independent web browser. A system overview, completed pilot project, and implementation experience to date will be presented

Advances in electrostatic accelerators

International Nuclear Information System (INIS)

Wegner, H.E.

1975-01-01

Advances in the design and performance of electrostatic accelerators since 1969 are reviewed with special emphasis on the ''forefront'' accelerators that are currently leading in voltage capability. A comparison of the acceleration tube design offered by the National Electrostatics Corporation and the High Voltage Engineering Corporation is also made. Other methods of increasing heavy ion energy by means of dual foil stripping are discussed as well as the performance of a newly developed sputter ion source for the production of negative heavy ions with reliability and flexibility that greatly exceeds all other present systems. Finally, new developments in terms of both booster systems and very high voltage electrostatic accelerators (25 to 60 MV) are discussed. (U.S.)

National plan for the accelerated commercialization of solar energy. Final report

Energy Technology Data Exchange (ETDEWEB)

None

1979-09-01

After a brief profile of the Mid-American region and characterization of the residential and commercial markets and the industry of the region, a short description is given of a regional planning meeting held for the purpose of preparing input for the Mid-American section of the National Program for the Accelerated Commercialization of Solar Energy (NPAC) Implementation plans. For each of thirty-eight programs, the objective, rationale, task statement/description, evaluation measures, and implementor are given. The programs are in these areas: public education/awareness; education/training; legislative/regulatory; performance/analysis; design/planning;demonstrations; state interface; technology; information dissemination; legal and regulatory; analysis and assessment; and regional coordination. Two policy statements are included - one on cratering a solar society and the other recommending the expansion of the commercialization to encompass and include the concepts of utilization and popularization in the plan for the advancement of solar energy. (LEW)

Operational status of the Brookhaven National Laboratory Accelerator Test Facility

International Nuclear Information System (INIS)

Batchelor, K.; Ben-Zvi, I.; Fernow, R.C.; Fischer, A.S.; Gallardo, J.; Jialin, Xie; Kirk, H.G.; Malone, R.G.; Parsa, Z.; Palmer, R.B.; Rao, T.; Rogers, J.; Sheehan, J.; Tsang, T.Y.F.; Ulc, S.; van Steenbergen, A.; Woodle, M.; Zhang, R.S.; Bigio, I.; Kurnit, N.; Shimada, T.; McDonald, K.T.; Russel, D.P.; Jiang, Z.Y.; Pellegrini, C.; Wang, X.J.

1990-01-01

Initial design parameters and early operational results of a 50 MeV high brightness electron linear accelerator are described. The system utilizes a radio frequency electron gun operating at a frequency of 2.856 GHz and a nominal output energy of 4.5 MeV followed by two, 2π/3 mode, disc loaded, traveling wave accelerating sections. The gun cathode is photo excited with short (6 psec) laser pulses giving design peak currents of a few hundred amperes. The system will be utilized to carry out infra-red FEL studies and investigation of new high gradient accelerating structures

Beam Diagnostics of the Compton Scattering Chamber in Jefferson Lab's Hall C

Science.gov (United States)

Faulkner, Adam; I&C Group Collaboration

2013-10-01

Upcoming experimental runs in Hall C will utilize Compton scattering, involving the construction and installation of a rectangular beam enclosure. Conventional cylindrical stripline-style Beam Position Monitors (BPMs) are not appropriate due to their form factor; therefore to facilitate measurement of position, button-style BPMs are being considered due to the ease of placement within the new beam enclosure. Button BPM experience is limited at JLAB, so preliminary measurements are needed to characterize the field response, and guide the development of appropriate algorithms for the Analog to Digital receiver systems. -field mapping is performed using a Goubau Line (G-Line), which employs a surface wave to mimic the electron beam, helping to avoid problems associated with vacuum systems. Potential algorithms include simplistic 1/r modeling (-field mapping), look-up-tables, as well as a potential third order power series fit. In addition, the use of neural networks specifically the multi-layer Perceptron will be examined. The models, sensor field maps, and utility of the neural network will be presented. Next steps include: modification of the control algorithm, as well as to run an in-situ test of the four Button electrodes inside of a mock beam enclosure. The analysis of the field response using Matlab suggests the button BPMs are accurate to within 10 mm, and may be successful for beam diagnostics in Hall C. More testing is necessary to ascertain the limitations of the new electrodes. The National Science Foundation, Old Dominion University, The Department of Energy, and Jefferson Lab.

Comparison of occipitocervical and atlantoaxial fusion in treatment of unstable Jefferson fractures

Directory of Open Access Journals (Sweden)

Yong Hu

2017-01-01

Full Text Available Background: Controversy exists regarding the management of unstable Jefferson fractures, with some surgeons performing reduction and immobilization of the patient in a halo vest and others performing open reduction and internal fixation. This study compares the clinical and radiological outcome parameters between posterior atlantoaxial fusion (AAF and occipitocervical fusion (OCF constructs in the treatment of the unstable atlas fracture. Materials and Methods: 68 consecutive patients with unstable Jefferson fractures treated by AAF or OCF between October 2004 and March 2011 were included in this retrospective evaluation from institutional databases. The authors reviewed medical records and original images. The patients were divided into two surgical groups treated with either AAF ( n = 48, F/M 30:18 and OCF ( n = 20, F/M 13:7 fusion. Blood loss, operative time, Japanese Orthopaedic Association (JOA score, visual analog scale (VAS score, atlanto-dens interval, lateral mass displacement, complications, and the bone fusion rates were recorded. Results: Five patients with incomplete paralysis (7.4% demonstrated postoperative improvement by more than 1 grade on the American Spinal Injury Association impairment scale. The JOA score of the AAF group improved from 12.5 ± 3.6 preoperatively to 15.7 ± 2.3 postoperatively, while the JOA score of the OCF group improved from 11.2 ± 3.3 preoperatively to 14.8 ± 4.2 postoperatively. The VAS score of AAF group decreased from 4.8 ± 1.5 preoperatively to 1.0 ± 0.4 postoperatively, the VAS score of the OCF group decreased from 5.4 ± 2.2 preoperatively to 1.3 ± 0.9 postoperatively. Conclusions: The OCF or AAF combined with short-term external immobilization can establish the upper cervical stability and prevent further spinal cord injury and nerve function damage.

JAERI 20 MV tandem accelerator

International Nuclear Information System (INIS)

Tsukada, Kineo; Harada, Kichinosuke

1977-01-01

Accelerators have been developed as the experimental apparatuses for the studies on nuclei and elementary particles. One direction of the development is the acceleration of protons and electrons to more and more high energy, and another direction is the acceleration of heavy ions up to uranium to several MeV up to several hundreds MeV. However recently, accelerators are used as the useful tools for the studies in wider fields. There are electrostatic acceleration and high frequency acceleration in ion acceleration, and at present, super-large accelerators are high frequency acceleration type. In Japan Atomic Energy Research Institute, it was decided in 1975 to construct an electrostatic accelerator of tandem type in order to accelerate heavy ions. In case of the electrostatic acceleration, the construction is relatively simple, the acceleration of heavy ions is easy, the property of the ion beam is very good, and the energy is stable. Especially, the tandem type is convenient for obtaining high energy. The tandem accelerator of 20 MV terminal voltage was ordered from the National Electrostatics Corp., USA, and is expected to be completed in 1978. The significance of heavy ion acceleration in the development and research of atomic energy, tandem van de Graaff accelerators, the JAERI 20MV tandem accelerator, and the research project with this accelerator are described. (Kako, I.)

Development of a high average current polarized electron source with long cathode operational lifetime

Energy Technology Data Exchange (ETDEWEB)

C. K. Sinclair; P. A. Adderley; B. M. Dunham; J. C. Hansknecht; P. Hartmann; M. Poelker; J. S. Price; P. M. Rutt; W. J. Schneider; M. Steigerwald

2007-02-01

Substantially more than half of the electromagnetic nuclear physics experiments conducted at the Continuous Electron Beam Accelerator Facility of the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory) require highly polarized electron beams, often at high average current. Spin-polarized electrons are produced by photoemission from various GaAs-based semiconductor photocathodes, using circularly polarized laser light with photon energy slightly larger than the semiconductor band gap. The photocathodes are prepared by activation of the clean semiconductor surface to negative electron affinity using cesium and oxidation. Historically, in many laboratories worldwide, these photocathodes have had short operational lifetimes at high average current, and have often deteriorated fairly quickly in ultrahigh vacuum even without electron beam delivery. At Jefferson Lab, we have developed a polarized electron source in which the photocathodes degrade exceptionally slowly without electron emission, and in which ion back bombardment is the predominant mechanism limiting the operational lifetime of the cathodes during electron emission. We have reproducibly obtained cathode 1/e dark lifetimes over two years, and 1/e charge density and charge lifetimes during electron beam delivery of over 2?105???C/cm2 and 200 C, respectively. This source is able to support uninterrupted high average current polarized beam delivery to three experimental halls simultaneously for many months at a time. Many of the techniques we report here are directly applicable to the development of GaAs photoemission electron guns to deliver high average current, high brightness unpolarized beams.

Biological applications of ultraviolet free-electron lasers

International Nuclear Information System (INIS)

Sutherland, J.C.

1997-10-01

This review examines the possibilities for biological research using the three ultraviolet free-electron lasers that are nearing operational status in the US. The projected operating characteristics of major interest in biological research of the free-electron lasers at Brookhaven National Laboratory, the Thomas Jefferson National Accelerator Facility, and Duke University are presented. Experimental applications in the areas of far- and vacuum ultraviolet photophysics and photochemistry, structural biology, environmental photobiology, and medical research are discussed and the prospects for advances in these areas, based upon the characteristics of the new ultraviolet free-electron lasers, are evaluated

Profiles of fast ions that are accelerated by high harmonic fast waves in the National Spherical Torus Experiment

International Nuclear Information System (INIS)

Liu, D; Heidbrink, W W; Podesta, M; Ruskov, E; Bell, R E; Fredrickson, E D; Medley, S S; Harvey, R W

2010-01-01

Combined neutral beam injection and high-harmonic fast-wave (HHFW) heating accelerate deuterium fast ions in the National Spherical Torus Experiment (NSTX). With 1.1 MW of HHFW power, the neutron emission rate is about three times larger than in the comparison discharge without HHFW heating. Acceleration of fast ions above the beam injection energy is evident on an E||B type neutral particle analyzer (NPA), a 4-chord solid state neutral particle analyzer (SSNPA) array and a 16-channel fast-ion D-alpha (FIDA) diagnostic. The accelerated fast ions observed by the NPA and SSNPA diagnostics mainly come from passive charge exchange reactions at the edge due to the NPA/SSNPA localization in phase space. The spatial profile of accelerated fast ions that is measured by the FIDA diagnostic is much broader than in conventional tokamaks because of the multiple resonance layers and large orbits in NSTX. The fast-ion distribution function calculated by the CQL3D Fokker-Planck code differs from the measured spatial profile, presumably because the current version of CQL3D uses a zero-banana-width model. In addition, compressional Alfven eigenmode activity is stronger during the HHFW heating and it may affect the fast-ion spatial profile.

The Brookhaven Accelerator Test Facility

International Nuclear Information System (INIS)

Batchelor, K.; Ben-Zvi, I.; Fernow, R.C.; Fischer, J.; Fisher, A.S.; Gallardo, J.; Jialin, Xie; Kirk, H.G.; Parsa, Z.; Palmer, R.B.; Rao, T.; Rogers, J.; Sheehan, J.; Tsang, T.Y.F.; Ulc, S.; Van Steenbergen, A.; Woodle, M.; Zhang, R.S.; McDonald, K.T.; Russell, D.P.; Jiang, Z.Y.; Pellegrini, C.; Wang, X.J.

1990-01-01

The Accelerator Test Facility (ATF), presently under construction at Brookhaven National laboratory, is described. It consists of a 50-MeV electron beam synchronizable to a high-peak power CO 2 laser. The interaction of electrons with the laser field will be probed, with some emphasis on exploring laser-based acceleration techniques. 5 refs., 2 figs

Resonance control for a CW accelerator

International Nuclear Information System (INIS)

Young, L.M.; Biddle, R.S.

1987-01-01

This paper describes a resonance-control technique that has been successfully applied to several cw accelerating structures built by the Los Alamos National Laboratory for the National Bureau of Standards and for the University of Illinois. The technique involves sensing the rf fields in an accelerating structure as well as the rf power feeding into the cavity and, then, using the measurement to control the resonant frequency of the structure by altering the temperature of the structure. The temperature of the structure is altered by adjusting the temperature of the circulating cooling water. The technique has been applied to continuous wave (cw) side-coupled cavities only but should have applications with most high-average-power accelerator structures. Some additional effort would be required for pulsed systems

The Los Alamos accelerator code group

International Nuclear Information System (INIS)

Krawczyk, F.L.; Billen, J.H.; Ryne, R.D.; Takeda, Harunori; Young, L.M.

1995-01-01

The Los Alamos Accelerator Code Group (LAACG) is a national resource for members of the accelerator community who use and/or develop software for the design and analysis of particle accelerators, beam transport systems, light sources, storage rings, and components of these systems. Below the authors describe the LAACG's activities in high performance computing, maintenance and enhancement of POISSON/SUPERFISH and related codes and the dissemination of information on the INTERNET

Maintenance information management using access/visual basic

International Nuclear Information System (INIS)

Memory A, Michael; Cumbia W, Brad

1998-01-01

The Accelerator Electronic Support Group (AES) is the group responsible for maintaining over 100 subsystems of the Nuclear Physics Accelerator at Jefferson Lab. Presently, there are 30 employees in the AES group. It is each individual's responsibility to make entries into the AES Database. This Access/Visual Basic based database is the center for all work performed to the Accelerator by the AES group. At any time, an AES technologist can supply valuable information needed to track pending maintenance, data analysis of recurring problems, inventory tracking and the ability to export all of this information to a web based electronic log generated by Jefferson Lab Operations Group

Operating experience with superconducting cavities at Jefferson Lab

International Nuclear Information System (INIS)

Reece, C.E.

1998-01-01

The CEBAF recirculating superconducting electron linac at Jefferson Lab is now in full operation supporting nuclear physics experiments in three target halls at up to 4.4 GeV. The 330 SRF cavities, operating at 2.0 K, continue to perform well above design specifications, and have accumulated over 8,000,000 operating cavity hours. The authors have to date no evidence of degradation of cavity performance. The SRF cavities have demonstrated excellent reliability. The one klystron per cavity design provides CEBAF with flexibility and redundancy for normal operations. Several techniques have been developed for establishing optimum operating conditions for the 330 independent systems. Operation of the cavities and control systems at the full design current of 1 mA has recently been achieved. The principal constraints on usable gradient for low current operations are (1) discharge at the cold ceramic rf window induced by electron field emission in cavities, (2) tuner controls, and (3) stability of the waveguide vacuum in the region between the warm and cold windows. Several cryomodules have been improved by application of rf helium processing while installed on the beamline

CAS Accelerator Physics (RF for Accelerators) in Denmark

CERN Multimedia

Barbara Strasser

2010-01-01

The CERN Accelerator School (CAS) and Aarhus University jointly organised a specialised course on RF for Accelerators, at the Ebeltoft Strand Hotel, Denmark from 8 to 17 June 2010.   Caption The challenging programme focused on the introduction of the underlying theory, the study and the performance of the different components involved in RF systems, the RF gymnastics and RF measurements and diagnostics. This academic part was supplemented with three afternoons dedicated to practical hands-on exercises. The school was very successful, with 100 participants representing 25 nationalities. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and excellent quality of their lectures. In addition to the academic programme, the participants were able to visit a small industrial exhibition organised by Aarhus University and take part in a one-day excursion consisting of a visit of the accelerators operated ...

The Los Alamos accelerator code group

Energy Technology Data Exchange (ETDEWEB)

Krawczyk, F.L.; Billen, J.H.; Ryne, R.D.; Takeda, Harunori; Young, L.M.

1995-05-01

The Los Alamos Accelerator Code Group (LAACG) is a national resource for members of the accelerator community who use and/or develop software for the design and analysis of particle accelerators, beam transport systems, light sources, storage rings, and components of these systems. Below the authors describe the LAACG`s activities in high performance computing, maintenance and enhancement of POISSON/SUPERFISH and related codes and the dissemination of information on the INTERNET.

A high-finesse Fabry–Perot cavity with a frequency-doubled green laser for precision Compton polarimetry at Jefferson Lab

International Nuclear Information System (INIS)

Rakhman, A.; Hafez, M.; Nanda, S.; Benmokhtar, F.; Camsonne, A.; Cates, G.D.; Dalton, M.M.; Franklin, G.B.; Friend, M.; Michaels, R.W.; Nelyubin, V.; Parno, D.S.; Paschke, K.D.; Quinn, B.P.

2016-01-01

A high-finesse Fabry–Perot cavity with a frequency-doubled continuous wave green laser (532 nm) has been built and installed in Hall A of Jefferson Lab for high precision Compton polarimetry. The infrared (1064 nm) beam from a ytterbium-doped fiber amplifier seeded by a Nd:YAG nonplanar ring oscillator laser is frequency doubled in a single-pass periodically poled MgO:LiNbO_3 crystal. The maximum achieved green power at 5 W infrared pump power is 1.74 W with a total conversion efficiency of 34.8%. The green beam is injected into the optical resonant cavity and enhanced up to 3.7 kW with a corresponding enhancement of 3800. The polarization transfer function has been measured in order to determine the intra-cavity circular laser polarization within a measurement uncertainty of 0.7%. The PREx experiment at Jefferson Lab used this system for the first time and achieved 1.0% precision in polarization measurements of an electron beam with energy and current of 1.06 GeV and 50 μA.

A high-finesse Fabry–Perot cavity with a frequency-doubled green laser for precision Compton polarimetry at Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Rakhman, A., E-mail: rahim@ornl.gov [Syracuse University, Department of Physics, Syracuse, NY 13244 (United States); Research Accelerator Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Hafez, M. [Old Dominion University, Applied Research Center, Norfolk, VA 23529 (United States); Nanda, S. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Benmokhtar, F. [Carnegie Mellon University, Department of Physics, Pittsburgh, PA 15213 (United States); Duquesne University, Pittsburgh, PA 15282 (United States); Camsonne, A. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Cates, G.D. [University of Virginia, Department of Physics, Charlottesville, VA 22904 (United States); Dalton, M.M. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); University of Virginia, Department of Physics, Charlottesville, VA 22904 (United States); Franklin, G.B. [Carnegie Mellon University, Department of Physics, Pittsburgh, PA 15213 (United States); Friend, M. [Carnegie Mellon University, Department of Physics, Pittsburgh, PA 15213 (United States); High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki (Japan); Michaels, R.W. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Nelyubin, V. [University of Virginia, Department of Physics, Charlottesville, VA 22904 (United States); Parno, D.S. [Carnegie Mellon University, Department of Physics, Pittsburgh, PA 15213 (United States); University of Washington, Center for Experimental Nuclear Physics and Astrophysics and Department of Physics, Seattle, WA 98195 (United States); Paschke, K.D. [University of Virginia, Department of Physics, Charlottesville, VA 22904 (United States); Quinn, B.P. [Carnegie Mellon University, Department of Physics, Pittsburgh, PA 15213 (United States); and others

2016-06-21

A high-finesse Fabry–Perot cavity with a frequency-doubled continuous wave green laser (532 nm) has been built and installed in Hall A of Jefferson Lab for high precision Compton polarimetry. The infrared (1064 nm) beam from a ytterbium-doped fiber amplifier seeded by a Nd:YAG nonplanar ring oscillator laser is frequency doubled in a single-pass periodically poled MgO:LiNbO{sub 3} crystal. The maximum achieved green power at 5 W infrared pump power is 1.74 W with a total conversion efficiency of 34.8%. The green beam is injected into the optical resonant cavity and enhanced up to 3.7 kW with a corresponding enhancement of 3800. The polarization transfer function has been measured in order to determine the intra-cavity circular laser polarization within a measurement uncertainty of 0.7%. The PREx experiment at Jefferson Lab used this system for the first time and achieved 1.0% precision in polarization measurements of an electron beam with energy and current of 1.06 GeV and 50 μA.

Recent progress of the advanced test accelerator

International Nuclear Information System (INIS)

Prono, D.S.

1985-01-01

The Advanced Test Accelerator (ATA) of Lawrence Livermore National Laboratory is a linear induction accelerator whose electron beam parameters are 10 kA, 50 MeV, and 70 ns. This accelerator structure basically is a 2.5 MeV injector followed by 190 identical induction accelerator cores each of which incrementally adds 250 kV to the electron beam as it threads the center of the core. Recent work on beam stability, beam emittance and beam brightness is reported

NIH/NSF accelerate biomedical research innovations

Science.gov (United States)

A collaboration between the National Science Foundation and the National Institutes of Health will give NIH-funded researchers training to help them evaluate their scientific discoveries for commercial potential, with the aim of accelerating biomedical in

The future of producing separated stable isotopes at Oak Ridge National Laboratory for accelerator applications

International Nuclear Information System (INIS)

Collins, E.D.

1994-01-01

Separated stable isotopes, produced in the calutrons at Oak Ridge National Laboratory, are essential target materials for production of numerous radioisotopes in accelerators and reactors. Recently, separated stable isotope production has been curtailed because government appropriations were discontinued and salts revenues decreased. The calutrons were placed in standby and the operating staff reduced to enable support by sales from existing inventories. Appeals were made to industry and government to preserve this national capability. Methods for providing volume-based price reductions were created to attract support from commercial isotope users. In 1994, the Department of Energy's Isotope Production and Distribution Program was restructured and a strategy produced to seek appropriated funding for the future production of rare, nonprofitable isotopes for research uses. This strategy, together with new demands for medical isotopes, will enable future operation of the calutrons. Moreover, production may be enhanced by complementing calutron capabilities with the Plasma Separation Process

25 MV tandem accelerator at Oak Ridge

International Nuclear Information System (INIS)

Jones, C.M.

1980-01-01

A new heavy-ion accelerator facility is under construction at the Oak Ridge National Laboratory. A brief description of the scope and status of this project is presented with emphasis on the first operational experience with the 25 MV tandem accelerator

Optimisation and calibration of the polarimeter Polder at Saturne. Experiment t20 at the Jefferson Laboratory: Measurement of the deuteron form factors

International Nuclear Information System (INIS)

Eyraud, Laurent

1998-01-01

The topic of this thesis is the made for the upgrade of the deuteron tensor polarimeter Polder, and its use in the so-called t 20 experiment at the Jefferson Laboratory (USA). The Polder polarimeter is based on the analysing reaction H(d → ,2p)n which makes possible the measurement of the tensor polarization of deuterons in the kinetic energy range 160 MeV - 520 MeV. The first part of this thesis describes the polarimeter and its performances as obtained during the calibration experiment at Saturne (Saclay, France). Specific developments of this polarimeter for the t 20 experiment (Wire Chambers with 3 detections planes, target, hodoscopes) are described. An acquisition system based on Fastbus-VME standard was developed and used during the calibration runs. The second part of the thesis is devoted to the t 20 experiment. The experimental devices, the CEBAF accelerator and the data analysis are presented. Finally the preliminary results for the polarization t 20 and the extraction of the electromagnetic form factors of the deuteron (G c , G q and G m ) for six values of the transferred momentum Q in the range of 4.11 - 6.8 fm -1 are presented and discussed along various theoretical models predictions. (author) [fr

Distribution uniformity of laser-accelerated proton beams

Science.gov (United States)

Zhu, Jun-Gao; Zhu, Kun; Tao, Li; Xu, Xiao-Han; Lin, Chen; Ma, Wen-Jun; Lu, Hai-Yang; Zhao, Yan-Ying; Lu, Yuan-Rong; Chen, Jia-Er; Yan, Xue-Qing

2017-09-01

Compared with conventional accelerators, laser plasma accelerators can generate high energy ions at a greatly reduced scale, due to their TV/m acceleration gradient. A compact laser plasma accelerator (CLAPA) has been built at the Institute of Heavy Ion Physics at Peking University. It will be used for applied research like biological irradiation, astrophysics simulations, etc. A beamline system with multiple quadrupoles and an analyzing magnet for laser-accelerated ions is proposed here. Since laser-accelerated ion beams have broad energy spectra and large angular divergence, the parameters (beam waist position in the Y direction, beam line layout, drift distance, magnet angles etc.) of the beamline system are carefully designed and optimised to obtain a radially symmetric proton distribution at the irradiation platform. Requirements of energy selection and differences in focusing or defocusing in application systems greatly influence the evolution of proton distributions. With optimal parameters, radially symmetric proton distributions can be achieved and protons with different energy spread within ±5% have similar transverse areas at the experiment target. Supported by National Natural Science Foundation of China (11575011, 61631001) and National Grand Instrument Project (2012YQ030142)

The CEBAF RF separator system

International Nuclear Information System (INIS)

Hovater, C.; Arnold, G.; Fugitt, J.; Harwood, L.; Kazimi, R.; Lahti, G.; Mammosser, J.; Nelson, R.; Piller, C.; Turlington, L.

1996-01-01

The 4 GeV CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) is arranged in a five-pass racetrack configuration, with two superconducting radio-frequency (SRF) linacs joined by independent magnetic transport arcs. The 1497 MHz continuous electron beam is composed of three interlaced variable-intensity 499 MHz beams that can be independently directed from any of the five passes to any of the three experimental halls. Beam extraction is made possible by a system of nine warm sub-harmonic separator cavities capable of delivering a 100 urad kick to any pass at a maximum machine energy of 6 GeV. Each separator cavity is a half-wavelength, two cell design with a high transverse shunt impedance and a small transverse dimension. The cavities are powered by 1 kW solid state amplifiers operating at 499 MHz. Cavity phase and gradient control are provided through a modified version of the same control module used for the CEBAF SRF cavity controls. The system has recently been tested while delivering beam to Hall C. In this paper we present a description of the RF separator system and recent test results with beam. (author)

Accelerator Mass Spectrometry at the National Institute of Nuclear Physics and Engineering in Bucharest

International Nuclear Information System (INIS)

Stan-Sion, C.; Catana, D.; Plostinaru, D.; Radulescu, M.; Enachescu, M.; Ivascu, M.; Marinescu, L.; Dima, R.

2000-01-01

The Accelerator Mass Spectrometry (AMS) is today the experimental physical method capable to measure the lowest concentration of a particular nuclide in a sample material. Ratios of radionuclides in the range 10 -13 - 10 -15 are normally measured with this technique, corresponding to a sensitivity which makes possible the detection of only 1 Atom in a surrounding material of about 1 Million of Billions of other Atoms. Thus, the AMS has advanced the art of Classical Mass Spectrometry (sensitivity 10 -11 ) to a sensitivity which allows for the first time the performance of special applications in environmental physics, medicine, pharmacology, geology, archaeology, measurements of radio nuclides in the Earth's atmosphere produced by cosmic-rays or by nuclear power plants, applications in astrophysics and in nuclear physics.An Accelerator Mass Spectrometry facility was constructed at the FN - 8 MV tandem accelerator of the National Institute of Physics and Nuclear Engineering . The construction was possible in the frame of a co-operation with the Technical University Munich and with financial support from IAEA-Vienna. It represents the first experimental set-up of this type in the large geographical area of Eastern Europe. The main components of the facility are: the ion injector deck, the AMS beam line and the detector systems. The injector deck is polarized at 50 kV and contains the high current sputtering ion source (spherical ionizer) followed, for beam transport, by electrostatic devices (single lenses, steerers, quadrupole lenses) a double focussing, 90 angle analyzing magnet (Danfysik), a pre-acceleration tube (NEC) and several diagnose and defining elements. The AMS samples are placed in an eight-stack magazine attached to the ion source. On the exit side of the tandem accelerator tank, a velocity filter and the particle detection system are mounted. The beam line, on the high-energy side, is optically achromatic and contains two 90 angle analyzing magnets of

Review of Advanced Accelerator Concepts R & D in Japan

Science.gov (United States)

Kitagawa, Yoneyoshi; Uesaka, Mitsuru; Koyama, Kazuyoshi; Nakajima, Kaszuhisa; Tajima, Toshiki; Daido, Hiroyuki; Ogata, Atsushi; Nemoto, Koshichi; Nishida, Yasushi; Yugami, Noboru; Miyamoto, Shuji; Dobashi, Katsuhiro

2004-12-01

More than 15 Japanese laboratories are dedicated to the advanced and compact accelerator development. Some use ultra-intense lasers and others use microwave concepts. As for the laser electron accleration, the topics are the capillary acceleration and the mono-energetic acceleration. The laser ion acceleration is also active. As well, the compatization is proceeding of the current rf accelerator. The National Institute for Radiological Science is promoting an advanced accelerator concept project mainly for the medical application.

Modular reliability modeling of the TJNAF personnel safety system

International Nuclear Information System (INIS)

Cinnamon, J.; Mahoney, K.

1997-01-01

A reliability model for the Thomas Jefferson National Accelerator Facility (formerly CEBAF) personnel safety system has been developed. The model, which was implemented using an Excel spreadsheet, allows simulation of all or parts of the system. Modularity os the model's implementation allows rapid open-quotes what if open-quotes case studies to simulate change in safety system parameters such as redundancy, diversity, and failure rates. Particular emphasis is given to the prediction of failure modes which would result in the failure of both of the redundant safety interlock systems. In addition to the calculation of the predicted reliability of the safety system, the model also calculates availability of the same system. Such calculations allow the user to make tradeoff studies between reliability and availability, and to target resources to improving those parts of the system which would most benefit from redesign or upgrade. The model includes calculated, manufacturer's data, and Jefferson Lab field data. This paper describes the model, methods used, and comparison of calculated to actual data for the Jefferson Lab personnel safety system. Examples are given to illustrate the model's utility and ease of use

Upgraded photon calorimeter with integrating readout for the Hall A Compton polarimeter at Jefferson Lab

International Nuclear Information System (INIS)

Friend, M.; Parno, D.; Benmokhtar, F.; Camsonne, A.; Dalton, M.M.; Franklin, G.B.; Mamyan, V.; Michaels, R.; Nanda, S.; Nelyubin, V.; Paschke, K.; Quinn, B.; Rakhman, A.; Souder, P.; Tobias, A.

2012-01-01

The photon arm of the Compton polarimeter in Hall A of Jefferson Lab has been upgraded to allow for electron beam polarization measurements with better than 1% accuracy. The data acquisition (DAQ) system now includes an integrating mode, which eliminates several systematic uncertainties inherent in the original counting-DAQ setup. The photon calorimeter has been replaced with a Ce-doped Gd 2 SiO 5 crystal, which has a bright output and fast response, and works well for measurements using the new integrating method at electron beam energies from 1 to 6 GeV.

Edward Gantt (1742-1837): US senate chaplain and first White House physician to Thomas Jefferson.

Science.gov (United States)

Cavanagh, Harrison Dwight

2017-08-01

In his long and eventful life, Edward Gantt (1742-1837) made important contributions to the newly independent American Republic, as well as to the development of scientific evidence-based American medicine. Unfortunately, his achievements have gone unrecognized and unreported in mainstream historical publications. Specifically, his service as the first designated White House doctor, and personal physician to President Thomas Jefferson from 1801 to 1809 has not been reported. The purpose of this paper is to document the biographical and scientific details of his extraordinary life and notable contributions.

Low Level RF System for Jefferson Lab Cryomodule Test Facility

International Nuclear Information System (INIS)

Tomasz Plawski; Trent Allison; Jean Delayen; J. Hovater; Thomas Powers

2003-01-01

The Jefferson Lab Cryomodule Test Facility (CMTF) has been upgraded to test and commission SNS and CEBAF Energy Upgrade cryomodules. Part of the upgrade was to modernize the superconducting cavity instrumentation and control. We have designed a VXI based RF control system exclusively for the production testing of superconducting cavities. The RF system can be configured to work either in Phase Locked Loop (PLL) or Self Excited Loop (SEL) mode. It can be used to drive either SNS 805 MHz or CEBAF Energy Upgrade 1497 MHz superconducting cavities and can be operated in pulsed or continuous wave (CW) mode. The base design consists of RF-analog and digital sections. The RF-analog section includes a Voltage Control Oscillator (VCO), phase detector, IandQ modulator and ''low phase shift'' limiter. The digital section controls the analog section and includes ADC, FPGA, and DAC . We will discuss the design of the RF system and how it relates to the support of cavity testing

Deeply Virtual Pseudoscalar Meson Production at Jefferson Lab and Transversity GPDs

Energy Technology Data Exchange (ETDEWEB)

Kubarovsky, Valery P. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2016-02-01

Transverse-momentum dependent parton distribution functions (TMDs) provide a description of nucleon structure in terms of the parton transverse momentum and its transverse spin. At leading twist there are eight TMDs, each offering a unique feature of quarks in a polarized or an unpolarized nucleon. The Sivers distribution is one of the most interesting TMD due to its non-universality. It has been extracted using the data from semi-inclusive deep-inelastic scattering (SIDIS), but there is no data yet from spin-dependent Drell-Yan (DY) process. Such measurement will provide a crucial test of TMD formalism which predicts an equal magnitude and opposite sign for the Sivers function extracted from SIDIS and DY process. We will discuss key future measurements of TMDs using both SIDIS and DY process with a focus on Hall A SoLID SIDIS program at Jefferson Lab.

New Results on Testing Duality in Spin Structure from Jefferson Lab

Energy Technology Data Exchange (ETDEWEB)

Nilanga Liyanage

2005-10-01

The Bloom-Gilman duality has been experimentally demonstrated for spin independent structure functions. Duality is observed when the smooth scaling curve at high momentum transfer is an average over the resonance bumps at lower momentum transfer, but at the same value of scaling variable x. Signs of quark-hadron duality for the spin Dependant structure function g1 of the proton has been recently reported by the Hermes collaboration. Experimental Halls A, B and C at Jefferson lab have recently measured spin structure functions in the resonance region for the proton and the neutron. Data from these experiments combined with Deep-Inelastic-Scattering data provide a precision test of quark-hadron duality predictions for spin structure functions for both the proton and the neutron. This will be one of the first precision tests of spin and flavor dependence of quark-hadron duality.

Status of national programmes on fast reactors and accelerator driven systems in Korea

International Nuclear Information System (INIS)

Hahn, Dohee; Kim, Yeong Il

2001-01-01

The LMR (liquid metal cooled reactors) Design Technology Development Project was approved as a national long-term R and D program in 1992 by the Korea Atomic Energy Commission (KAEC). KAEC decided to develop and construct an LMR with the goal of developing an LMR that can serve as a long term power supplier with competitive economics and enhanced safety. Based upon the KAEC decision, the Korea Atomic Energy Research Institute (KAERI) has been developing KALIMER (Korea Advanced Liquid Metal Reactor). According to the revised National Nuclear Energy Promotion Plan of June 1997, the basic design of KALIMER is to be completed by 2006 and feasibility of the construction is to be examined sometime during the mid 2010s. Phase 1 of three years of the LMR Design Technology Development Project was completed in March 2000 and a preliminary conceptual design report has been issued. The conceptual design of KALIMER will be finalized during Phase 2 of the project, which was started in April 2000 and will take two years. KAERI is also carrying out research and development on an accelerator driven system, called HYPER, for the transmutation of nuclear waste and energy production through the transmutation process. The HYPER program is being performed within the framework of the national mid- and long-term nuclear research plan. KAERI aims to develop a system concept and type of roadmap by the year 2001, and to complete conceptual design of the HYPER system by the year 2007. (author)

Low-velocity superconducting accelerating structures

International Nuclear Information System (INIS)

Delayen, J.R.

1990-01-01

The present paper reviews the status of RF superconductivity as applied to low-velocity accelerating properties. Heavy-ion accelerators must accelerate efficiently particles which travel at a velocity much smaller than that of light particles, whose velocity changes along accelerator, and also different particles which have different velocity profiles. Heavy-ion superconducting accelerators operate at frequencies which are lower than high-energy superconducting accelerators. The present paper first discusses the basic features of heavy-ion superconducting structures and linacs. Design choices are then addressed focusing on structure geometry, materials, frequency, phase control, and focusing. The report also gives an outline of the status of superconducting booster projects currently under way at the Argonne National Laboratory, SUNY Stony Brook, Weizmann Institute, University of Washington, Florida State, Saclay, Kansas State, Daresbury, Japanese Atomic Energy Research Institute, Legnaro, Bombay, Sao Paulo, ANU (Canberra), and Munich. Recent developments and future prospects are also described. (N.K.) 68 refs

Preliminary Results from Integrating Compton Photon Polarimetry in Hall A of Jefferson Lab

International Nuclear Information System (INIS)

Parno, D; Friend, M; Benmokhtar, F; Franklin, G; Quinn, B; Michaels, R; Nanda, S; Souder, P

2011-01-01

A wide range of nucleon and nuclear structure experiments in Jefferson Lab's Hall A require precise, continuous measurements of the polarization of the electron beam. In our Compton polarimeter, electrons are scattered off photons in a Fabry-Perot cavity; by measuring an asymmetry in the integrated signal of the scattered photons detected in a GSO crystal, we can make non-invasive, continuous measurements of the beam polarization. Our goal is to achieve 1% statistical error within two hours of running. We discuss the design and commissioning of an upgrade to this apparatus, and report preliminary results for experiments conducted at beam energies from 3.5 to 5.9 GeV and photon rates from 5 to 100 kHz.

Semantic eScience for Ecosystem Understanding and Monitoring: The Jefferson Project Case Study

Science.gov (United States)

McGuinness, D. L.; Pinheiro da Silva, P.; Patton, E. W.; Chastain, K.

2014-12-01

Monitoring and understanding ecosystems such as lakes and their watersheds is becoming increasingly important. Accelerated eutrophication threatens our drinking water sources. Many believe that the use of nutrients (e.g., road salts, fertilizers, etc.) near these sources may have negative impacts on animal and plant populations and water quality although it is unclear how to best balance broad community needs. The Jefferson Project is a joint effort between RPI, IBM and the Fund for Lake George aimed at creating an instrumented water ecosystem along with an appropriate cyberinfrastructure that can serve as a global model for ecosystem monitoring, exploration, understanding, and prediction. One goal is to help communities understand the potential impacts of actions such as road salting strategies so that they can make appropriate informed recommendations that serve broad community needs. Our semantic eScience team is creating a semantic infrastructure to support data integration and analysis to help trained scientists as well as the general public to better understand the lake today, and explore potential future scenarios. We are leveraging our RPI Tetherless World Semantic Web methodology that provides an agile process for describing use cases, identification of appropriate background ontologies and technologies, implementation, and evaluation. IBM is providing a state-of-the-art sensor network infrastructure along with a collection of tools to share, maintain, analyze and visualize the network data. In the context of this sensor infrastructure, we will discuss our semantic approach's contributions in three knowledge representation and reasoning areas: (a) human interventions on the deployment and maintenance of local sensor networks including the scientific knowledge to decide how and where sensors are deployed; (b) integration, interpretation and management of data coming from external sources used to complement the project's models; and (c) knowledge about

DevLore - A Firmware Library and Web-Based Configuration Control Tool for Accelerator Systems Under Constant Development

International Nuclear Information System (INIS)

Richard Evans; Kevin Jordan; Deborah Gruber; Daniel Sexton

2005-01-01

The Free Electron Laser Project at Jefferson Lab is based on a comparatively small accelerator driver. As it's systems continues to grow and evolve, strict configuration control has not been a programmatic goal. Conversely, as the IR-Demo FEL and the 10kW IR FEL have been built and operated, hardware and software changes have been regular part of the machine development process. With relatively small component counts for sub-systems, changes occur without requiring much formal documentation and in-situ alterations are common-place in the name of supporting operations. This paper presents an overview of the web-based software tool called DevLore which was first developed to be a library for embedded programming and then became a tremendously effective tool for tracking all changes made to the machine hardware and software

Advance in Vertical Buffered Electropolishing on Niobium for Particle Accelerators

International Nuclear Information System (INIS)

Wu, A.T.; Jin, S.; Mammosser, J.D.; Reece, C.E.; Rimmer, R.A.; Lin, L.; Lu, X.Y.; Zhao, K.

2011-01-01

Niobium (Nb) is the most popular material that has been employed for making superconducting radio frequency (SRF) cavities to be used in various particle accelerators over the last couple of decades. One of the most important steps in fabricating Nb SRF cavities is the final chemical removal of 150 μm of Nb from the inner surfaces of the SRF cavities. This is usually done by either buffered chemical polishing (BCP) or electropolishing (EP). Recently a new Nb surface treatment technique called buffered electropolishing (BEP) has been developed at Jefferson Lab. It has been demonstrated that BEP can produce the smoothest surface finish on Nb ever reported in the literature while realizing a Nb removal rate as high as 10 μm/min that is more than 25 and 5 times quicker than those of EP and BCP(112) respectively. In this contribution, recent advance in optimizing and understanding BEP treatment technique is reviewed. Latest results from RF measurements on BEP treated Nb single cell cavities by our unique vertical polishing system will be reported.

Testing of a Plasmadynamic Hypervelocity Dust Accelerator

Science.gov (United States)

Ticos, Catalin M.; Wang, Zhehui; Dorf, Leonid A.; Wurden, G. A.

2006-10-01

A plasmadynamic accelerator for microparticles (or dust grains) has been designed, built and tested at Los Alamos National laboratory. The dust grains are expected to be accelerated to hypervelocities on the order of 1-30 km/s, depending on their size. The key components of the plasmadynamic accelerator are a coaxial plasma gun operated at 10 kV, a dust dispenser activated by a piezoelectric transducer, and power and remote-control systems. The coaxial plasma gun produces a high density (10^18 cm-3) and low temperature (˜ 1 eV) plasma in deuterium ejected by J x B forces, which provides drag on the dust particles in its path. Carbon dust particles will be used, with diameters from 1 to 50 μm. The plasma parameters produced in the coaxial gun are presented and their implication to dust acceleration is discussed. High speed dust will be injected in the National Spherical Torus Experiment to measure the pitch angle of magnetic field lines.

A versatile scalable PET processing system

International Nuclear Information System (INIS)

Dong, H.; Weisenberger, A.; McKisson, J.; Wenze, Xi; Cuevas, C.; Wilson, J.; Zukerman, L.

2011-01-01

Positron Emission Tomography (PET) historically has major clinical and preclinical applications in cancerous oncology, neurology, and cardiovascular diseases. Recently, in a new direction, an application specific PET system is being developed at Thomas Jefferson National Accelerator Facility (Jefferson Lab) in collaboration with Duke University, University of Maryland at Baltimore (UMAB), and West Virginia University (WVU) targeted for plant eco-physiology research. The new plant imaging PET system is versatile and scalable such that it could adapt to several plant imaging needs - imaging many important plant organs including leaves, roots, and stems. The mechanical arrangement of the detectors is designed to accommodate the unpredictable and random distribution in space of the plant organs without requiring the plant be disturbed. Prototyping such a system requires a new data acquisition system (DAQ) and data processing system which are adaptable to the requirements of these unique and versatile detectors.

Transport of LCLS-II 1.3 Ghz cryomodule to SLAC

Energy Technology Data Exchange (ETDEWEB)

McGee, M. W.; Arkan, T.; Peterson, T.; Tang, Z.; Boo, S.; Carrasco, M.; Daly, E.; Huque, N.

2016-06-30

In a partnership with SLAC National Accelerator Laboratory (SLAC) and Jefferson Lab, Fermilab will assemble and test 17 of the 35 total 1.3 GHz cryomodules for the Linac Coherent Light Source II (LCLS-II) Project. These include a prototype built and delivered by each Lab. Another two 3.9 GHz cryomodules will be built, tested and transported by Fermilab to SLAC. Each assembly will be transported over-the-road from Fermilab or Jefferson Lab using specific routes to SLAC. The transport system consists of a base frame, isolation fixture and upper protective truss. The strongback cryomodule lifting fixture is described along with other supporting equipment used for both over-the-road transport and local (on-site) transport at Fermilab. Initially, analysis of fragile components and stability studies will be performed in order to assess the risk associated with over-the-road transport of a fully assembled cryomodule.

An aerial radiological survey of the Fermi National Accelerator Laboratory and surrounding area, Batavia, Illinois

International Nuclear Information System (INIS)

Fritzsche, A.E.

1990-11-01

An aerial radiological gamma survey was conducted over the Fermi National Accelerator Laboratory during 1 through 6 June 1989. Flight lines at 150-foot altitude and 250-foot line spacings assured nearly 100% coverage. The terrestrial exposure at about 6 μR/h was nearly the same as that measured by the previous survey of this area (May 1977). Ten anomalous areas, mostly Na-22 and Mn-54, were detected within buildings and laboratories in the area. Although these locations have changed somewhat from the 1977 survey, the aerial data shows good agreement with the ground-based ion chamber and soil sample data. 7 refs., 15 figs., 1 tab

The United States Particle Accelerator School: Educating the Next Generation of Accelerator Scientists and Engineers

International Nuclear Information System (INIS)

Barletta, William A.

2009-01-01

Only a handful of universities in the US offer any formal training in accelerator science. The United States Particle Accelerator School (USPAS) is National Graduate Educational Program that has developed a highly successful educational paradigm that, over the past twenty-years, has granted more university credit in accelerator/beam science and technology than any university in the world. Sessions are held twice annually, hosted by major US research universities that approve course credit, certify the USPAS faculty, and grant course credit. The USPAS paradigm is readily extensible to other rapidly developing, cross-disciplinary research areas such as high energy density physics.

The United States Particle Accelerator School: Educating the next generation of accelerator scientists and engineers

International Nuclear Information System (INIS)

Barletta, William A.

2008-01-01

Only a handful of universities in the US offer any formal training in accelerator science. The United States Particle Accelerator School (USPAS) is National Graduate Educational Program that has developed a highly successful educational paradigm that, over the past twenty-years, has granted more university credit in accelerator / beam science and technology than any university in the world. Sessions are held twice annually, hosted by major US research universities that approve course credit, certify the USPAS faculty, and grant course credit. The USPAS paradigm is readily extensible to other rapidly developing, crossdisciplinary research areas such as high energy density physics

Two Exceptional Witnesses of Latin American Independence: The Prussian Explorer Alexander Von Humboldt and The Virginian Politician Thomas Jefferson

Directory of Open Access Journals (Sweden)

Sandra Rebok

2014-01-01

Full Text Available Este artículo analiza las respectivas posturas de Alexander von Humboldt y Thomas Jefferson en relación con la independencia de los territorios hispanoamericanos y el modo en que estas se hallaban condicionadas por sus propias experiencias: Humboldt, como observador de la situación americana justo antes del comienzo de los movimientos independentistas; y Jefferson, como actor importante en la independencia de los EE.UU. y la posterior creación de una nueva sociedad. Asimismo, no se pueden estudiar sus respectivas posiciones hacia los movimientos independentistas en la América española, desvinculadas de sus conclusiones respecto a la Revolución francesa y sus consecuencias. El trabajo muestra de qué manera los dos personajes comentaron estos sucesos en la correspondencia que mantuvieron entre sí. Finalmente, también se evalúan, a través de estos famosos representantes del llamado Nuevo Mundo y el Viejo Mundo, las diferencias y similitudes en la manera de reaccionar ante estos eventos políticos y sociales desde el punto de vista europeo, en comparación con la mirada desde Norteamérica.

SSC accelerator availability allocation

International Nuclear Information System (INIS)

Dixon, K.T.; Franciscovich, J.

1991-03-01

Superconducting Super Collider (SSC) operational availability is an area of major concern, judged by the Central Design Group to present such risk that use of modern engineering tools would be essential to program success. Experience has shown that as accelerator beam availability falls below about 80%, efficiency of physics experiments degrades rapidly due to inability to maintain adequate coincident accelerator and detector operation. For this reason, the SSC availability goal has been set at 80%, even though the Fermi National Accelerator Laboratory accelerator, with a fraction of the SSC's complexity, has only recently approached that level. This paper describes the allocation of the top-level goal to part-level reliability and maintainability requirements, and it gives the results of parameter sensitivity studies designed to help identify the best approach to achieve the needed system availability within funding and schedule constraints. 1 ref., 12 figs., 4 tabs

BNL accelerator plans

International Nuclear Information System (INIS)

Lowenstein, D.I.

1986-01-01

The Brookhaven National Laboratory plan for high energy and heavy ion physics accelerator use for the next ten-year period is described. The two major initiatives are in the construction of the Relativistic Heavy Ion Collider and the upgrade of the Alternating Gradient Synchrotron to a ''Mini Kaon Factory''

Development of a high average current polarized electron source with long cathode operational lifetime

Directory of Open Access Journals (Sweden)

C. K. Sinclair

2007-02-01

Full Text Available Substantially more than half of the electromagnetic nuclear physics experiments conducted at the Continuous Electron Beam Accelerator Facility of the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory require highly polarized electron beams, often at high average current. Spin-polarized electrons are produced by photoemission from various GaAs-based semiconductor photocathodes, using circularly polarized laser light with photon energy slightly larger than the semiconductor band gap. The photocathodes are prepared by activation of the clean semiconductor surface to negative electron affinity using cesium and oxidation. Historically, in many laboratories worldwide, these photocathodes have had short operational lifetimes at high average current, and have often deteriorated fairly quickly in ultrahigh vacuum even without electron beam delivery. At Jefferson Lab, we have developed a polarized electron source in which the photocathodes degrade exceptionally slowly without electron emission, and in which ion back bombardment is the predominant mechanism limiting the operational lifetime of the cathodes during electron emission. We have reproducibly obtained cathode 1/e dark lifetimes over two years, and 1/e charge density and charge lifetimes during electron beam delivery of over 2×10^{5}   C/cm^{2} and 200 C, respectively. This source is able to support uninterrupted high average current polarized beam delivery to three experimental halls simultaneously for many months at a time. Many of the techniques we report here are directly applicable to the development of GaAs photoemission electron guns to deliver high average current, high brightness unpolarized beams.

Unique electron polarimeter analyzing power comparison and precision spin-based energy measurement

International Nuclear Information System (INIS)

Joseph Grames; Charles Sinclair; Joseph Mitchell; Eugene Chudakov; Howard Fenker; Arne Freyberger; Douglas Higinbotham; Poelker, B.; Michael Steigerwald; Michael Tiefenback; Christian Cavata; Stephanie Escoffier; Frederic Marie; Thierry Pussieux; Pascal Vernin; Samuel Danagoulian; Kahanawita Dharmawardane; Renee Fatemi; Kyungseon Joo; Markus Zeier; Viktor Gorbenko; Rakhsha Nasseripour; Brian Raue; Riad Suleiman; Benedikt Zihlmann

2004-01-01

Precision measurements of the relative analyzing powers of five electron beam polarimeters, based on Compton, Moller, and Mott scattering, have been performed using the CEBAF accelerator at the Thomas Jefferson National Accelerator Facility (Jefferson Laboratory). A Wien filter in the 100 keV beamline of the injector was used to vary the electron spin orientation exiting the injector. High statistical precision measurements of the scattering asymmetry as a function of the spin orientation were made with each polarimeter. Since each polarimeter receives beam with the same magnitude of polarization, these asymmetry measurements permit a high statistical precision comparison of the relative analyzing powers of the five polarimeters. This is the first time a precise comparison of the analyzing powers of Compton, Moller, and Mott scattering polarimeters has been made. Statistically significant disagreements among the values of the beam polarization calculated from the asymmetry measurements made with each polarimeter reveal either errors in the values of the analyzing power, or failure to correctly include all systematic effects. The measurements reported here represent a first step toward understanding the systematic effects of these electron polarimeters. Such studies are necessary to realize high absolute accuracy (ca. 1%) electron polarization measurements, as required for some parity violation measurements planned at Jefferson Laboratory. Finally, a comparison of the value of the spin orientation exiting the injector that provides maximum longitudinal polarization in each experimental hall leads to an independent and very precise (better than 10-4) absolute measurement of the final electron beam energy

ATOM - Accelerating Therapeutics for Opportunities in Medicine | FNLCR Staging

Science.gov (United States)

The Frederick National Lab is a founding member of the Accelerating Therapeutics for Opportunities in Medicine (ATOM) Consortium,a public-private partnership with themission oftransforming drug discovery by accelerating the deve

Radiation safety training for accelerator facilities

International Nuclear Information System (INIS)

Trinoskey, P.A.

1997-02-01

In November 1992, a working group was formed within the U.S. Department of Energy's (DOE's) accelerator facilities to develop a generic safety training program to meet the basic requirements for individuals working in accelerator facilities. This training, by necessity, includes sections for inserting facility-specific information. The resulting course materials were issued by DOE as a handbook under its technical standards in 1996. Because experimenters may be at a facility for only a short time and often at odd times during the day, the working group felt that computer-based training would be useful. To that end, Lawrence Livermore National Laboratory (LLNL) and Argonne National Laboratory (ANL) together have developed a computer-based safety training program for accelerator facilities. This interactive course not only enables trainees to receive facility- specific information, but time the training to their schedule and tailor it to their level of expertise

Evaluating the Potential of Commercial GIS for Accelerator Configuration Management

International Nuclear Information System (INIS)

Larrieu, T.L.; Roblin, Y.R.; White, K.; Slominski, R.

2005-01-01

The Geographic Information System (GIS) is a tool used by industries needing to track information about spatially distributed assets. A water utility, for example, must know not only the precise location of each pipe and pump, but also the respective pressure rating and flow rate of each. In many ways, an accelerator such as CEBAF (Continuous Electron Beam Accelerator Facility) can be viewed as an ''electron utility''. Whereas the water utility uses pipes and pumps, the ''electron utility'' uses magnets and RF cavities. At Jefferson lab we are exploring the possibility of implementing ESRI's ArcGIS as the framework for building an all-encompassing accelerator configuration database that integrates location, configuration, maintenance, and connectivity details of all hardware and software. The possibilities of doing so are intriguing. From the GIS, software such as the model server could always extract the most-up-to-date layout information maintained by the Survey and Alignment for lattice modeling. The Mechanical Engineering department could use ArcGIS tools to generate CAD drawings of machine segments from the same database. Ultimately, the greatest benefit of the GIS implementation could be to liberate operators and engineers from the limitations of the current system-by-system view of machine configuration and allow a more integrated regional approach. The commercial GIS package provides a rich set of tools for database-connectivity, versioning, distributed editing, importing and exporting, and graphical analysis and querying, and therefore obviates the need for much custom development. However, formidable challenges to implementation exist and these challenges are not only technical and manpower issues, but also organizational ones. The GIS approach would crosscut organizational boundaries and require departments, which heretofore have had free reign to manage their own data, to cede some control and agree to a centralized framework

Evaluating the Potential of Commercial GIS for Accelerator Configuration Management

Energy Technology Data Exchange (ETDEWEB)

T.L. Larrieu; Y.R. Roblin; K. White; R. Slominski

2005-10-10

The Geographic Information System (GIS) is a tool used by industries needing to track information about spatially distributed assets. A water utility, for example, must know not only the precise location of each pipe and pump, but also the respective pressure rating and flow rate of each. In many ways, an accelerator such as CEBAF (Continuous Electron Beam Accelerator Facility) can be viewed as an ''electron utility''. Whereas the water utility uses pipes and pumps, the ''electron utility'' uses magnets and RF cavities. At Jefferson lab we are exploring the possibility of implementing ESRI's ArcGIS as the framework for building an all-encompassing accelerator configuration database that integrates location, configuration, maintenance, and connectivity details of all hardware and software. The possibilities of doing so are intriguing. From the GIS, software such as the model server could always extract the most-up-to-date layout information maintained by the Survey & Alignment for lattice modeling. The Mechanical Engineering department could use ArcGIS tools to generate CAD drawings of machine segments from the same database. Ultimately, the greatest benefit of the GIS implementation could be to liberate operators and engineers from the limitations of the current system-by-system view of machine configuration and allow a more integrated regional approach. The commercial GIS package provides a rich set of tools for database-connectivity, versioning, distributed editing, importing and exporting, and graphical analysis and querying, and therefore obviates the need for much custom development. However, formidable challenges to implementation exist and these challenges are not only technical and manpower issues, but also organizational ones. The GIS approach would crosscut organizational boundaries and require departments, which heretofore have had free reign to manage their own data, to cede some control and agree to a

Applications of proton and deuteron accelerators

Energy Technology Data Exchange (ETDEWEB)

Todd, A.M.M. (Grumman Corporate Research Center, Princeton, NJ (United States))

1993-06-01

Applications of positive and negative hydrogen and deuterium ion accelerators beyond basic research are increasing. Large scale proposed national laboratory/industrial projects include the Accelerator Production of Tritium (APT) which will utilize protons, and the International Fusion Material Irradiation Facility (IFMIF) which will accelerate a deuteron beam into a lithium target. At the small scale end, radio-frequency quadrupole (RFQ) accelerator based systems have been built for neutron activation analysis and for applications such as explosive detection. At an intermediate scale, the Loma Linda proton therapy accelerator is now successfully treating a full schedule of patients, and more than half a dozen such hospital based units are under active study world-wide. At this same scale, there are also several ongoing negative ion, military accelerator projects which include the Continuous Wave Deuterium Demonstrator (CWDD) and the Neutral Particle Beam Space Experiment (NPBSE). These respective deuterium and hydrogen accelerators, which have not been previously described, are the focus of this paper. (orig.)

Economic feasibility study to Raise the operational capacity of the Electron Beam Accelerator at the National Centre for Radiation Research and Technology, atomic Energy Authority, Egypt

International Nuclear Information System (INIS)

El-Kolaly, M.; Hammad, A.; El-Gameel, E.A.

2011-01-01

The study aims to investigate the economic feasibility to raise the operational capacity of the accelerator at the National Center for Radiation Research and Technology, Atomic Energy Authority, Egypt, through proposal of additional processing of power cables as it have 4 thousand operating hours per year of total 6 thousand hours per year. The study involved three sections; the first section included the technical aspects and marketing, the second section was concerned with financial analysis, and the third section included the national return of the project. In the first part, the electronic and technical requirements of the accelerator were studied to raise the capacity of the accelerator and to identify the time trend of demand for services in marketing. The second section included the financial feasibility of the project which was carried out through two parts; the first part deal with the analysis of costs of the project including identifying of investment, spending, labor costs, operating expenses, the annual installment of the annual depreciation expense with the total annual costs and operating costs per hour and ton. The second part was carried out to evaluated business profitability of the project, preparation of the annual cash flow, calculation of the internal rate of return, payback period of capital, and the analysis of sensitivity of the project in terms of its ability to achieve profitable business in the event of increasing costs and decreasing revenue. The third section was carried out to raise the operational capacity of the accelerator at the Egyptian Atomic Energy Authority to generate added value for national income, and to study the social rate of return for the project and examine the project's ability to provide new employment opportunities. The study showed the possibility and the importance of the project implemented at the level of private investment and national security.

New accelerator mass spectrometry radiocarbon ages for the Mazama tephra layer from Kootenay National Park, British Columbia, Canada

International Nuclear Information System (INIS)

Hallett, D.J.; Hills, L.V.; Clague, J.J.

1997-01-01

Charcoal fragments recovered from the Mazama air-fall tephra layer in cores from Dog and Cobb lakes, Kootenay National Park, British Columbia, yielded accelerator mass spectrometry ages of 6720 ± 70 and 6760 ± 70 14 C years BP, respectively. These two new ages, together with other previously published radiocarbon ages on charcoal and twig fragments from Mazama air-fall deposits, indicate that the climatic eruption of Mount Mazama occurred 6730 ± 40 14 C years BP. (author)

The Spallation Neutron Source accelerator system design

Science.gov (United States)

Henderson, S.; Abraham, W.; Aleksandrov, A.; Allen, C.; Alonso, J.; Anderson, D.; Arenius, D.; Arthur, T.; Assadi, S.; Ayers, J.; Bach, P.; Badea, V.; Battle, R.; Beebe-Wang, J.; Bergmann, B.; Bernardin, J.; Bhatia, T.; Billen, J.; Birke, T.; Bjorklund, E.; Blaskiewicz, M.; Blind, B.; Blokland, W.; Bookwalter, V.; Borovina, D.; Bowling, S.; Bradley, J.; Brantley, C.; Brennan, J.; Brodowski, J.; Brown, S.; Brown, R.; Bruce, D.; Bultman, N.; Cameron, P.; Campisi, I.; Casagrande, F.; Catalan-Lasheras, N.; Champion, M.; Champion, M.; Chen, Z.; Cheng, D.; Cho, Y.; Christensen, K.; Chu, C.; Cleaves, J.; Connolly, R.; Cote, T.; Cousineau, S.; Crandall, K.; Creel, J.; Crofford, M.; Cull, P.; Cutler, R.; Dabney, R.; Dalesio, L.; Daly, E.; Damm, R.; Danilov, V.; Davino, D.; Davis, K.; Dawson, C.; Day, L.; Deibele, C.; Delayen, J.; DeLong, J.; Demello, A.; DeVan, W.; Digennaro, R.; Dixon, K.; Dodson, G.; Doleans, M.; Doolittle, L.; Doss, J.; Drury, M.; Elliot, T.; Ellis, S.; Error, J.; Fazekas, J.; Fedotov, A.; Feng, P.; Fischer, J.; Fox, W.; Fuja, R.; Funk, W.; Galambos, J.; Ganni, V.; Garnett, R.; Geng, X.; Gentzlinger, R.; Giannella, M.; Gibson, P.; Gillis, R.; Gioia, J.; Gordon, J.; Gough, R.; Greer, J.; Gregory, W.; Gribble, R.; Grice, W.; Gurd, D.; Gurd, P.; Guthrie, A.; Hahn, H.; Hardek, T.; Hardekopf, R.; Harrison, J.; Hatfield, D.; He, P.; Hechler, M.; Heistermann, F.; Helus, S.; Hiatt, T.; Hicks, S.; Hill, J.; Hill, J.; Hoff, L.; Hoff, M.; Hogan, J.; Holding, M.; Holik, P.; Holmes, J.; Holtkamp, N.; Hovater, C.; Howell, M.; Hseuh, H.; Huhn, A.; Hunter, T.; Ilg, T.; Jackson, J.; Jain, A.; Jason, A.; Jeon, D.; Johnson, G.; Jones, A.; Joseph, S.; Justice, A.; Kang, Y.; Kasemir, K.; Keller, R.; Kersevan, R.; Kerstiens, D.; Kesselman, M.; Kim, S.; Kneisel, P.; Kravchuk, L.; Kuneli, T.; Kurennoy, S.; Kustom, R.; Kwon, S.; Ladd, P.; Lambiase, R.; Lee, Y. Y.; Leitner, M.; Leung, K.-N.; Lewis, S.; Liaw, C.; Lionberger, C.; Lo, C. C.; Long, C.; Ludewig, H.; Ludvig, J.; Luft, P.; Lynch, M.; Ma, H.; MacGill, R.; Macha, K.; Madre, B.; Mahler, G.; Mahoney, K.; Maines, J.; Mammosser, J.; Mann, T.; Marneris, I.; Marroquin, P.; Martineau, R.; Matsumoto, K.; McCarthy, M.; McChesney, C.; McGahern, W.; McGehee, P.; Meng, W.; Merz, B.; Meyer, R.; Meyer, R.; Miller, B.; Mitchell, R.; Mize, J.; Monroy, M.; Munro, J.; Murdoch, G.; Musson, J.; Nath, S.; Nelson, R.; Nelson, R.; O`Hara, J.; Olsen, D.; Oren, W.; Oshatz, D.; Owens, T.; Pai, C.; Papaphilippou, I.; Patterson, N.; Patterson, J.; Pearson, C.; Pelaia, T.; Pieck, M.; Piller, C.; Plawski, T.; Plum, M.; Pogge, J.; Power, J.; Powers, T.; Preble, J.; Prokop, M.; Pruyn, J.; Purcell, D.; Rank, J.; Raparia, D.; Ratti, A.; Reass, W.; Reece, K.; Rees, D.; Regan, A.; Regis, M.; Reijonen, J.; Rej, D.; Richards, D.; Richied, D.; Rode, C.; Rodriguez, W.; Rodriguez, M.; Rohlev, A.; Rose, C.; Roseberry, T.; Rowton, L.; Roybal, W.; Rust, K.; Salazer, G.; Sandberg, J.; Saunders, J.; Schenkel, T.; Schneider, W.; Schrage, D.; Schubert, J.; Severino, F.; Shafer, R.; Shea, T.; Shishlo, A.; Shoaee, H.; Sibley, C.; Sims, J.; Smee, S.; Smith, J.; Smith, K.; Spitz, R.; Staples, J.; Stein, P.; Stettler, M.; Stirbet, M.; Stockli, M.; Stone, W.; Stout, D.; Stovall, J.; Strelo, W.; Strong, H.; Sundelin, R.; Syversrud, D.; Szajbler, M.; Takeda, H.; Tallerico, P.; Tang, J.; Tanke, E.; Tepikian, S.; Thomae, R.; Thompson, D.; Thomson, D.; Thuot, M.; Treml, C.; Tsoupas, N.; Tuozzolo, J.; Tuzel, W.; Vassioutchenko, A.; Virostek, S.; Wallig, J.; Wanderer, P.; Wang, Y.; Wang, J. G.; Wangler, T.; Warren, D.; Wei, J.; Weiss, D.; Welton, R.; Weng, J.; Weng, W.-T.; Wezensky, M.; White, M.; Whitlatch, T.; Williams, D.; Williams, E.; Wilson, K.; Wiseman, M.; Wood, R.; Wright, P.; Wu, A.; Ybarrolaza, N.; Young, K.; Young, L.; Yourd, R.; Zachoszcz, A.; Zaltsman, A.; Zhang, S.; Zhang, W.; Zhang, Y.; Zhukov, A.

2014-11-01

The Spallation Neutron Source (SNS) was designed and constructed by a collaboration of six U.S. Department of Energy national laboratories. The SNS accelerator system consists of a 1 GeV linear accelerator and an accumulator ring providing 1.4 MW of proton beam power in microsecond-long beam pulses to a liquid mercury target for neutron production. The accelerator complex consists of a front-end negative hydrogen-ion injector system, an 87 MeV drift tube linear accelerator, a 186 MeV side-coupled linear accelerator, a 1 GeV superconducting linear accelerator, a 248-m circumference accumulator ring and associated beam transport lines. The accelerator complex is supported by ~100 high-power RF power systems, a 2 K cryogenic plant, ~400 DC and pulsed power supply systems, ~400 beam diagnostic devices and a distributed control system handling ~100,000 I/O signals. The beam dynamics design of the SNS accelerator is presented, as is the engineering design of the major accelerator subsystems.

Technologies using accelerator-driven targets under development at BNL

International Nuclear Information System (INIS)

Van Tuyle, G.J.

1994-01-01

Recent development work conducted at Brookhaven National Laboratory on technologies which use particle accelerator-driven targets is summarized. These efforts include development of the Spallation-Induced Lithium Conversion (SILC) Target for the Accelerator Production of Tritium (APT), the Accelerator-Driven Assembly for Plutonium Transformation (ADAPT) Target for the Accelerator-Based Conversion (ABC) of excess weapons plutonium. The PHOENIX Concept for the accelerator-driven transmutation of minor actinides and fission products from the waste stream of commercial nuclear power plants, and other potential applications

Hadron accelerators in cancer therapy

International Nuclear Information System (INIS)

Amaldi, U.; Silari, M.

1997-01-01

The application of hadron accelerators (protons and light ions) in cancer therapy is discussed. After a brief introduction on the rationale for the use of heavy charged particles in radiation therapy, a discussion is given on accelerator technology and beam delivery systems. Next, existing and planned facilities are briefly reviewed. The Italian Hadrontherapy Project (the largest project of this type in Europe) is then described, with reference to both the National Centre for Oncological Hadrontherapy and the design of two types of compact proton accelerators aimed at introducing proton therapy in a large number of hospitals. Finally, the radiation protection requirements are discussed. (author)

The Radiological Research Accelerator Facility

International Nuclear Information System (INIS)

Hall, E.J.; Marino, S.A.

1990-07-01

The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) -- formerly the Radiological Research Laboratory (RRL) -- of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). Fifteen different experiments were run during these 12 months, approximately the same as the previous two years. Brief summaries of each experiment are included. Accelerator usage is summarized and development activities are discussed. 7 refs., 4 tabs

The transfer of accelerator technology to industry

International Nuclear Information System (INIS)

Favale, A.

1992-01-01

The national laboratories and universities are sources for innovative accelerator technology developments. With the growing application of accelerators in such fields as semiconductor manufacturing, medical therapy isotope production, nuclear waste transmutation, materials testing, bomb detection, pure science, etc., it is becoming more important to transfer these technologies and build an accelerator industrial base. In this talk the methods of technology transfer, the issues involved in working with the labs and examples of successful technology transfers are discussed. (Author)

CAS course on Plasma Wake Acceleration

CERN Multimedia

CERN Accelerator School

2015-01-01

The CERN Accelerator School (CAS) recently organised a specialised course on Plasma Wake Acceleration, held at CERN, Geneva, Switzerland, from 23 to 29 November 2014.    Following a number of introductory lectures on laser and plasma physics, as well as an overview of conventional accelerators and their limitations, the course covered a large number of aspects of plasma wake acceleration schemes: the creation of plasma by high power lasers or particle beams, a description of the plasma creation process through simulations and the characteristics of the accelerated particle beams, including results of the latest achievements. Lectures on beam diagnostics, the applications of plasma accelerated beams, and topical seminars completed the programme.  The course was very successful, with 109 students of 26 nationalities attending; most participants coming from European counties, but also from the US, Israel, India, South Korea, Russia and Ukraine. Feedback from the participants was...

Debris flow from 2012 failure of moraine-dammed lake, Three Fingered Jack volcano, Mount Jefferson Wilderness, Oregon

Science.gov (United States)

Sherrod, David R.; Wills, Barton B.

2014-01-01

In the late spring or early summer of 2012, a flood emanated from a small moraine-dammed lake on the northeast flank of Three Fingered Jack in the Mount Jefferson Wilderness. Channel erosion or slope collapse breached the natural dam of the lake, leading to a sudden lowering of lake level by 2.8 m and discharge of 12,700 cubic meters (m3) of water. The resulting debris flow formed a bouldery deposit extending about 0.35 km downslope.

Proposed measurement of tagged deep inelastic scattering in Hall A of Jefferson lab

Energy Technology Data Exchange (ETDEWEB)

Montgomery, Rachel [Univ. of Glasgow, Scotland (United Kingdom); Annand, John [Univ. of Glasgow, Scotland (United Kingdom); Dutta, Dipangkar [Mississippi State Univ., Mississippi State, MS (United States); Keppel, Cynthia E. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); King, Paul [The Ohio State Univ., Columbus, OH (United States). Dept of Physics; Wojtsekhowski, Bogdan [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Zhang, Jixie [Univ. of Virginia, Charlottesville, VA (United States)

2017-03-01

A tagged deep inelastic scattering (TDIS) experiment is planned for Hall A of Jefferson Lab, which will probe the mesonic content of the nucleon directly. Low momentum recoiling (and spectator) protons will be measured in coincidence with electrons scattered in a deep inelastic regime from hydrogen (and deuterium) targets, covering kinematics of 8 < W2 < 18 GeV2, 1 < Q2 < 3 (GeV/c)2 and 0:05 < x < 0:2. The tagging technique will help identify scattering from partons in the meson cloud and provide access to the pion structure function via the Sullivan process. The experiment will yield the first TDIS results in the valence regime, for both proton and neutron targets. We present here an overview of the experiment.

Electroproduction of neutral pions in the Hall A at the Jefferson Laboratory; Electroproduction de pions neutres dans le Hall A au Jefferson Laboratory

Energy Technology Data Exchange (ETDEWEB)

Fuchey, Eric [Blaise Pascal Univ., Aubiere (France)

2010-06-01

The past decade has seen a strong evolution of the study of the hadron structure through exclusive processes, allowing to access to a more complete description of this structure. Exclusive processes include DVCS (Deeply Virtual Compton Scattering) as well as hard exclusive meson production. This document is particularly focussed on the latter, and more particularly on exclusive neutral pion production. In this thesis is described the analysis of triple coincidence events H(e, e'γγ)X, which were a consequent by-product of the DVCS experiment which occured during Fall 2004 at Jefferson Lab Hall A, to extract the ep → epπ⁰ cross section. This cross section has been measured at two values of four-momentum transfer Q² = 1.9 GeV² and Q² = 2.3 GeV². The statistical precision for these measurements is achieved at better than 5 %. The kinematic range allows to study the evolution of the extracted cross section as a function of Q² and W. Results are be confronted with Regge inspired calculations and Generalized (GPD) predictions. An intepretation of our

Joint International Accelerator School

CERN Multimedia

CERN Accelerator School

2014-01-01

The CERN and US Particle Accelerator Schools recently organised a Joint International Accelerator School on Beam Loss and Accelerator Protection, held at the Hyatt Regency Hotel, Newport Beach, California, USA from 5-14 November 2014. This Joint School was the 13th in a series of such schools, which started in 1985 and also involves the accelerator communities in Japan and Russia.   Photo courtesy of Alfonse Pham, Michigan State University.   The school attracted 58 participants representing 22 different nationalities, with around half from Europe and the other half from Asia and the Americas. The programme comprised 26 lectures, each of 90 minutes, and 13 hours of case study. The students were given homework each day and had an opportunity to sit a final exam, which counted towards university credit. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and quality of their lectures. Initial dis...

National health expenditure projections: modest annual growth until coverage expands and economic growth accelerates.

Science.gov (United States)

Keehan, Sean P; Cuckler, Gigi A; Sisko, Andrea M; Madison, Andrew J; Smith, Sheila D; Lizonitz, Joseph M; Poisal, John A; Wolfe, Christian J

2012-07-01

For 2011-13, US health spending is projected to grow at 4.0 percent, on average--slightly above the historically low growth rate of 3.8 percent in 2009. Preliminary data suggest that growth in consumers' use of health services remained slow in 2011, and this pattern is expected to continue this year and next. In 2014, health spending growth is expected to accelerate to 7.4 percent as the major coverage expansions from the Affordable Care Act begin. For 2011 through 2021, national health spending is projected to grow at an average rate of 5.7 percent annually, which would be 0.9 percentage point faster than the expected annual increase in the gross domestic product during this period. By 2021, federal, state, and local government health care spending is projected to be nearly 50 percent of national health expenditures, up from 46 percent in 2011, with federal spending accounting for about two-thirds of the total government share. Rising government spending on health care is expected to be driven by faster growth in Medicare enrollment, expanded Medicaid coverage, and the introduction of premium and cost-sharing subsidies for health insurance exchange plans.

Superconductivity and future accelerators

International Nuclear Information System (INIS)

Danby, G.T.; Jackson, J.W.

1963-01-01

For 50 years particle accelerators employing accelerating cavities and deflecting magnets have been developed at a prodigious rate. New accelerator concepts and hardware ensembles have yielded great improvements in performance and GeV/$. The great idea for collective acceleration resulting from intense auxiliary charged-particle beams or laser light may or may not be just around the corner. In its absence, superconductivity (SC) applied both to rf cavities and to magnets opened up the potential for very large accelerators without excessive energy consumption and with other economies, even with the cw operation desirable for colliding beams. HEP has aggressively pioneered this new technology: the Fermilab single ring 1 TeV accelerator - 2 TeV collider is near the testing stage. Brookhaven National Laboratory's high luminosity pp 2 ring 800 GeV CBA collider is well into construction. Other types of superconducting projects are in the planning stage with much background R and D accomplished. The next generation of hadron colliders under discussion involves perhaps a 20 TeV ring (or rings) with 40 TeV CM energy. This is a very large machine: even if the highest practical field B approx. 10T is used, the radius is 10x that of the Fermilab accelerator. An extreme effort to get maximum GeV/$ may be crucial even for serious consideration of funding

Accelerator programme at CAT

International Nuclear Information System (INIS)

Ramamurthi, S.S.

1991-01-01

The Accelerator Programme at the Centre for Advanced Technology (CAT), Indore, has very broad based concept under which all types of accelerators are to be taken up for design and fabrication. This centre will be housing a wide variety of accelerators to serve as a common facility for the universities, national laboratories in addition to laboratories under the Department of Atomic Energy. In the first phase of the programme, a series of electron accelerators are designed and fabricated. They are synchrotron radiation sources of 450 MeV (INDUS-I) and of 2 GeV (INDUS-II), microtron upto energy of 20 MeV, linear accelerator upto 20 MeV, and DC Accelerator for industrial irradiation upto 750 KeV and 20 KW. A proton accelerator of 300 MeV with 20 MeV linac injector is also designed. CAT is also developing a strong base for support technologies like ultra high vacuum, radio frequency and microwaves, DC pulsed and superconducting magnets, power supplies and controls etc. These technologies are very useful for other industrial applications also. To develop user groups to utilise INDUS-II synchrotron radiation source, a batch production of rotating Anode X-ray generators with power supplies has been initiated. So also, the sputter ion pumps, electron guns, turbo molecular pumps are brought into batch production. (author)

Thomas Jefferson, I dilemmi della democrazia americana, translated and edited by Alberto Giordano, with a preface by Dino Cofrancesco (Novi Ligure: Città del Silenzio, 2007

Directory of Open Access Journals (Sweden)

Pierluigi Chiassoni

2010-03-01

Full Text Available A review of Thomas Jefferson, I dilemmi della democrazia americana, translated and edited by Alberto Giordano, with a preface by Dino Cofrancesco (Novi Ligure: Città del Silenzio, 2007

Versatile Data Acquisition and Controls for EPICS using VME-based FPGAs

International Nuclear Information System (INIS)

Trent Allison; Roger Flood

2001-01-01

Field Programmable Gate Arrays (FPGAs) have provided versatile VME based data acquisition and control systems with minimal development times for the Thomas Jefferson National Accelerator Facility (Jefferson Lab). FPGAs have been used to interface with VME controllers using both standard A16 and A24 address modes. VME vector-interrupt capability has also been implemented for timing issues in some applications. FPGA designs have additionally been used to provide controls for various systems by interfacing with Analog to Digital Converters (DAC), interlocks, and other drive signals. These controls can be molded to the individual needs of each system and can provide operators with indicators and controls in EPICS via a VME interface. This allows the developer to choose components and make specifications that are not available commercially. Jefferson Lab has begun developing standard FPGA libraries that result in quick turnaround times and inexpensive designs. There have been approximately eight VME based FPGA designs implanted in one department at Jefferson Lab and they are becoming more widespread. FPGAs continue to become larger and faster enabling systems to be incorporated on one integrated circuit. Inherently, FPGAs can process data faster than many microprocessors due to the small processing overhead associated with a custom FPGA design. The ability to modify FPGA code enables the developer to easily implement future additions to a system, making the design flexible and expandable. This work supported by the U.S. DOE Contract No. DE-AC05-84ER40150

A multipurpose accelerator facility for Kharkov National Scientific Center

International Nuclear Information System (INIS)

Bulyak, E.; Dolbnya, A.; Gladkikh, P.; Karnaukhov, I.; Kononenko, S.; Kozin, V.; Lapshin, V.; Mytsykov, A.; Peev, F.; Shcherbakov, A.; Tarasenko, A.; Telegin, Yu.; Zelinsky, A.

2000-01-01

The project of the multifunctional accelerator storage ring complex with electron energy of up to 2 GeV is described. The lattice of the complex was chosen taking into account of the existing equipment, layout of the buildings, and infrastructure of the 2 GeV electron linear accelerator, the necessity of obtaining precise parameters of photon and electron beams, and the economic efficiency. The principle parameters of the storage ring are the circumference of 91 m, the energy range 0.3-2.0 GeV, the natural beam emittance 25 nm and the stored beam current 0.5 A. This complex are provided with photon beams (6-7 beam lines at first stage, up to 20 later on) and CW electron beams (energy region 0.3-0.5 GeV) for scientific and industrial application

A multipurpose accelerator facility for Kharkov National Scientific Center

Energy Technology Data Exchange (ETDEWEB)

Bulyak, E.; Dolbnya, A.; Gladkikh, P.; Karnaukhov, I.; Kononenko, S.; Kozin, V.; Lapshin, V.; Mytsykov, A.; Peev, F.; Shcherbakov, A. E-mail: shcherbakov@kipt.kharkov.ua; Tarasenko, A.; Telegin, Yu.; Zelinsky, A

2000-06-21

The project of the multifunctional accelerator storage ring complex with electron energy of up to 2 GeV is described. The lattice of the complex was chosen taking into account of the existing equipment, layout of the buildings, and infrastructure of the 2 GeV electron linear accelerator, the necessity of obtaining precise parameters of photon and electron beams, and the economic efficiency. The principle parameters of the storage ring are the circumference of 91 m, the energy range 0.3-2.0 GeV, the natural beam emittance 25 nm and the stored beam current 0.5 A. This complex are provided with photon beams (6-7 beam lines at first stage, up to 20 later on) and CW electron beams (energy region 0.3-0.5 GeV) for scientific and industrial application.

A multipurpose accelerator facility for Kharkov National Scientific Center

CERN Document Server

Bulyak, E V; Gladkikh, P; Karnaukhov, I; Kononenko, S; Kozin, V; Lapshin, V G; Mytsykov, A; Peev, F; Shcherbakov, A; Tarasenko, A; Telegin, Yu P; Zelinsky, A

2000-01-01

The project of the multifunctional accelerator storage ring complex with electron energy of up to 2 GeV is described. The lattice of the complex was chosen taking into account of the existing equipment, layout of the buildings, and infrastructure of the 2 GeV electron linear accelerator, the necessity of obtaining precise parameters of photon and electron beams, and the economic efficiency. The principle parameters of the storage ring are the circumference of 91 m, the energy range 0.3-2.0 GeV, the natural beam emittance 25 nm and the stored beam current 0.5 A. This complex are provided with photon beams (6-7 beam lines at first stage, up to 20 later on) and CW electron beams (energy region 0.3-0.5 GeV) for scientific and industrial application.

Resonance control for a cw [continuous wave] accelerator

International Nuclear Information System (INIS)

Young, L.M.; Biddle, R.S.

1987-01-01

A resonance-control technique is described that has been successfully applied to several cw accelerating structures built by the Los Alamos National Laboratory for the National Bureau of Standards and for the University of Illinois. The technique involves sensing the rf fields in an accelerating structure as well as the rf power feeding into the cavity and, then, using the measurement to control the resonant frequency of the structure by altering the temperature of the structure. The temperature of the structure is altered by adjusting the temperature of the circulating cooling water. The technique has been applied to continuous wave (cw) side-coupled cavities only but should have applications with most high-average-power accelerator structures. Some additional effort would be required for pulsed systems

Accelerator system model (ASM): A unique tool in exploring accelerator driven transmutation technologies (ADTT) system trade space

Energy Technology Data Exchange (ETDEWEB)

Myers, T.J.; Favale, A.J.; Berwald, D.H.; Burger, E.C.; Paulson, C.C.; Peacock, M.A.; Piaszczyk, C.M.; Piechowiak, E.M.; Rathke, J.W. [Northrop Grumman Corp., Bethpage, NY (United States). Advanced Technology and Development Center

1997-09-01

To aid in the development and optimization of emerging Accelerator Driven Transmutation Technology (ADTT) concepts, the Northrop Grumman Corporation, working together with G.H. Gillespie Associates and Los Alamos National Laboratory has developed a computational tool which combines both accelerator physics layout/analysis capabilities with engineering analysis capabilities to create a standardized platform to compare and contrast accelerator system configurations. In this context, the accelerator system configuration includes not only the accelerating structures, but also the major support systems such as the vacuum, thermal control, RF power, and cryogenic subsystem (if superconducting accelerator operation is investigated) as well as estimates of the costs for enclosures (accelerating tunnel and RF halls). This paper presents an overview of the Accelerator System Model (ASM) code flow, as well as a discussion of the data and analysis upon which it is based. Also presented is material which addresses the development of the evaluation criteria employed by this code including a presentation of the economic analysis methods, and a discussion of the cost database employed. The paper concludes with examples depicting completed and planned trade studies for both normal and superconducting accelerator applications. 8 figs.

Review of national accelerator driven system programmes for partitioning and transmutation. Proceedings of an advisory group meeting

International Nuclear Information System (INIS)

2003-08-01

One of the current important issues of nuclear power is the long lived radioactive waste toxicity problem. The sharpness of this problem could be considerably reduced if, during energy production, there was the possibility to incinerate at least the most toxic radioactive isotopes (long lived fission products and minor actinides). The combination of external intensive neutron sources with facilities containing nuclear fuel, so-called hybrid systems, are under investigation in several countries. The surplus of neutrons in such systems may be used to convert most of the long lived radioactive nuclides into isotopes having a shorter lifetime. Currently, an increasing number of groups are entering this field of research. There is clearly a need for co-originated their efforts, and also for the exchange of information from nationally or internationally co-ordinated activities. Consideration of the advantages of hybrid systems, and the wide field of interdisciplinary areas of research involved, show the need for an international co-operation in this novel R and D area. The International Atomic Energy Agency has maintained an active interest in advanced nuclear technology related to accelerator driven systems (ADS), and related activities have been carried out within the framework of its programme on emerging nuclear energy systems. After thorough analyses of the outcomes of several international forums and recommendations of the IAEA Technical Committee Meeting on Feasibility and Motivation for Hybrid Concepts for Nuclear Energy Generation and Transmutation (Madrid, Spain, 1997), the IAEA conducted an Advisory Group Meeting on Review of National Accelerator Driven System Programmes in Taejon, Republic of Korea, from 1 to 4 November 1999. The scope of the meeting included review of the current R and D programmes in the Member States and the assessment of the progress in the development of hybrid concepts. The programme of the AGM included the following topics

Mass spectrometry by means of tandem accelerators

International Nuclear Information System (INIS)

Tuniz, C.

1985-01-01

Mass spectrometry based on an accelerator allows to measure rare cosmogenic isotopes found in natural samples with isotopic abundances up to 10E-15. The XTU Tandem of Legnaro National Laboratories can measure mean heavy isotopes (36Cl, 41Ca, 129I) in applications interesting cosmochronology and Medicine. The TTT-3 Tandem of the Naples University has been modified in view of precision studies of C14 in Archeology, Paleantology and Geology. In this paper a review is made of principles and methodologies and of some applicationy in the framework of the National Program for mass spectrametry research with the aid of accelerators

The production of cyclotron radioisotopes and radiopharmaceuticals at the national accelerator centre in South Africa

International Nuclear Information System (INIS)

Walt, T.N. van der

1998-01-01

Accelerator radioisotopes have been manufactured in South Africa since 1965 with the 30 MeV cyclotron at the Council for Scientific and Industrial Research (CSIR) in Pretoria. After its closure in 1988, the radioisotope production programme was continued at the National Accelerator Centre (NAC) with the 200 MeV separated sector cyclotron (SCC) utilizing the 66 MeV proton beam, which is shared with the neutron therapy programme during part of the week. A variety of radiopharmaceuticals, such as 18 F-FDG, 67 Ga-citrate, a 67 Ga-labelled resin. 111 In-chloride, 111 In-oxine and 111 In-labelled resin. 123 I-sodium iodide and 123 I-labelled compounds, 201 Tl-chloride, as well as the 81 Rb/ 81m Kr gas generator, are prepared for use in the nuclear medicine departments of 12 State hospitals and about 28 private nuclear medicine clinics in South Africa. A few longer-lived radioisotopes, such as 22 Na, 55 Fe and 139 Ce, are also produced for research or industrial use. A research and development programme is running to develop new production procedures to produce radioisotopes and radiopharmaceuticals, or to improve existing production procedures. As part of a programme to utilize the beam time optimally, the production of some other radioisotopes is investigated. (author)

Future accelerators in Japan

International Nuclear Information System (INIS)

Toge, Nobu

1993-01-01

This paper presents a brief report on the present status of future accelerator projects at the National Laboratory for High Energy Physics (KEK), Japan. The KEK laboratory has been successfully operating the TRISTAN accelerator complex since 1986. It consists of a 2.5 GeV electron/positron linac, an 8 GeV Accumulation Ring (AR) and a 29 GeV Main Ring (MR). Concurrently with this operation, in response to recommendations by the Japanese High Energy Physics Committee, survey studies have been continued on new accelerator facilities at KEK. They have two major future projects, namely, the asymmetric e + e - B-factory based on TRISTAN (TRISTAN-II) and the Japan Linear Collider (JLC). The purpose of this paper is to outline those research activities and to present an update on their status

A silicon strip detector used as a high rate focal plane sensor for electrons in a magnetic spectrometer

CERN Document Server

Miyoshi, T; Fujii, Y; Hashimoto, O; Hungerford, E V; Sato, Y; Sarsour, M; Takahashi, T; Tang, L; Ukai, M; Yamaguchi, H

2003-01-01

A silicon strip detector was developed as a focal plane sensor for a 300 MeV electron spectrometer and operated in a high rate environment. The detector with 500 mu m pitch provided good position resolution for electrons crossing the focal plane of the magnetic spectrometer system which was mounted in Hall C of the Thomas Jefferson National Accelerator Facility. The design of the silicon strip detector and the performance under high counting rate (<=2.0x10 sup 8 s sup - sup 1 for approx 1000 SSD channels) and high dose are discussed.

Linear induction accelerators at the Los Alamos National Laboratory DARHT facility

International Nuclear Information System (INIS)

Nath, Subrata

2010-01-01

The Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) at Los Alamos National Laboratory consists of two linear induction accelerators at right angles to each other. The First Axis, operating since 1999, produces a nominal 20-MeV, 2-kA single beam-pulse with 60-nsec width. In contrast, the DARHT Second Axis, operating since 2008, produces up to four pulses in a variable pulse format by slicing micro-pulses out of a longer ∼1.6-microseconds (flat-top) pulse of nominal beam-energy and -current of 17 MeV and 2 kA respectively. Bremsstrahlung x-rays, shining on a hydro-dynamical experimental device, are produced by focusing the electron beam-pulses onto a high-Z target. Variable pulse-formats allow for adjustment of the pulse-to-pulse doses to record a time sequence of x-ray images of the explosively driven imploding mock device. Herein, we present a sampling of the numerous physics and engineering aspects along with the current status of the fully operational dual axes capability. First successful simultaneous use of both the axes for a hydrodynamic experiment was achieved in 2009.

Studies of niobium and development of niobium resonant RF cavities for accelerator driven system

International Nuclear Information System (INIS)

Mondal, Jayanta

2013-01-01

The present approach for the fabrication of superconducting radio frequency (SRF) cavities is to roll and deep draw sheets of polycrystalline high-purity niobium. Jefferson Laboratory pioneered the use of large-grain/single-crystal Nb directly sliced from an ingot for the fabrication of single-crystal high-purity Nb SRF cavities. The large grain/single crystal niobium has several potential advantages over the polycrystalline niobium and has become a viable alternative to the standard fine grain (ASTM grain size>6 μm), high purity (RRR ≥ 250 ) niobium for the fabrication of high-performance SRF cavities for particle accelerators. The present study includes the prototype single cell low beta cavity design, fabrication, EB welding and low temperature RF test at 2K. In this study also the medium field Q-Slope has been analyzed with the help of an added non linear term in Heabel's analytical model and a linear increase of surface resistance Rs with the magnetic field

Software Design Concepts for Archiving and Retrieving Control System Data

International Nuclear Information System (INIS)

Christopher Larrieu; Matt Bickley

2001-01-01

To develop and operate the control system effectively at the Thomas Jefferson National Accelerator Facility, users require the ability to diagnose its behavior not only in real-time, but also in retrospect. The new Jefferson Lab data logging system provides an acquisition and storage component capable of archiving enough data to provide suitable context for such analyses. In addition, it provides an extraction and presentation-facility which efficiently fulfills requests for both raw and processed data. This paper discusses several technologies and design methodologies which contribute to the system's overall utility. The Application Programming Interface (API) which developers use to access the data derives from a view of the storage system as a specialized relational database. An object-oriented and compartmental design contributes to its portability at several levels, and the use of CORBA facilitates interaction between distributed components in an industry-standard fashion. This work was supported by the U.S. DOE contract No. DE-AC05-84ER40150

Space-charge-dominated beam dynamics simulations using the massively parallel processors (MPPs) of the Cray T3D

International Nuclear Information System (INIS)

Liu, H.

1996-01-01

Computer simulations using the multi-particle code PARMELA with a three-dimensional point-by-point space charge algorithm have turned out to be very helpful in supporting injector commissioning and operations at Thomas Jefferson National Accelerator Facility (Jefferson Lab, formerly called CEBAF). However, this algorithm, which defines a typical N 2 problem in CPU time scaling, is very time-consuming when N, the number of macro-particles, is large. Therefore, it is attractive to use massively parallel processors (MPPs) to speed up the simulations. Motivated by this, the authors modified the space charge subroutine for using the MPPs of the Cray T3D. The techniques used to parallelize and optimize the code on the T3D are discussed in this paper. The performance of the code on the T3D is examined in comparison with a Parallel Vector Processing supercomputer of the Cray C90 and an HP 735/15 high-end workstation

Nucleon Structure Studies with Electromagnetic Probes

International Nuclear Information System (INIS)

Vineyard, Michael F.

2011-01-01

Summarized in this report is the progress achieved during the period from March 1, 2008 to June 14, 2009 under contract number DE-FG02-03ER41252. This is the final technical report under this contract. The experimental work described here is part of the electromagnetic nuclear physics program of the CEBAF Large Acceptance Spectrometer (CLAS) Collaboration at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) that published 17 journal articles during the period of this report. One of these journal articles reported on the results of precise measurements of the neutron magnetic form factor. I was a spokesperson on this experiment and the publication of these results is the culmination of years of effort by a small subset of the CLAS Collaboration. As usual, undergraduate students were involved in all aspects of this work. Three Union College students participated in this program during the window of this report and one presented a paper on his work at the 2009 National Conference on Undergraduate Research (NCUR22). In this report, I discuss recent progress on the measurements of the neutron magnetic form factor and describe my service work for the CLAS Collaboration.

Overview of Fermi National Accelerator Lab Control System

International Nuclear Information System (INIS)

Lucas, P.W.

1990-01-01

Various facets of the control of the Fermilab accelerators, in particular the Tevatron, are presented. Since Fermilab contains a superconducting machine and a sophisticated injection complex, much of the controls functionality will of necessity be the same at the SSC. The various functions required at a large laboratory are discussed; these include computer-based fire and security alarms and a cable television system, as well as computer networks connected to accelerator hardware components. A description is given of that hardware, of which much is Camac but with considerable computer backplane bus equipment also present. A large fraction of the controls hardware has access to high precision real-time clocks. Our various networks are introduced, with the physical layer being a combination of copper and more modern optic cables, with the primary intercomputer link being Token Ring. A description of the computers is presented - basically these consist of operators' consoles, host VAXs, and link driving front ends. The software effort is detailed, with emphasis on consoles and microprocessors where the majority of effort has been placed. Future plans for the system are presented briefly. 3 refs., 2 figs., 2 tabs

Depleted uranium risk assessment for Jefferson Proving Ground using data from environmental monitoring and site characterization. Final report

International Nuclear Information System (INIS)

Ebinger, M.H.; Hansen, W.R.

1996-10-01

This report documents the third risk assessment completed for the depleted uranium (DU) munitions testing range at Jefferson Proving Ground (JPG), Indiana, for the U.S. Army Test and Evaluation command. Jefferson Proving Ground was closed in 1995 under the Base Realignment and Closure Act and the testing mission was moved to Yuma Proving Ground. As part of the closure of JPG, assessments of potential adverse health effects to humans and the ecosystem were conducted. This report integrates recent information obtained from site characterization surveys at JPG with environmental monitoring data collected from 1983 through 1994 during DU testing. Three exposure scenarios were evaluated for potential adverse effects to human health: an occasional use scenario and two farming scenarios. Human exposure was minimal from occasional use, but significant risk were predicted from the farming scenarios when contaminated groundwater was used by site occupants. The human health risk assessments do not consider the significant risk posed by accidents with unexploded ordnance. Exposures of white-tailed deer to DU were also estimated in this study, and exposure rates result in no significant increase in either toxicological or radiological risks. The results of this study indicate that remediation of the DU impact area would not substantially reduce already low risks to humans and the ecosystem, and that managed access to JPG is a reasonable model for future land use options

Radiation therapy for pineal tumors: 30-year experience at Thomas Jefferson University Hospital

International Nuclear Information System (INIS)

Dickerson, G.A.; Tupchong, L.; Moylan, D.J.; Kramer, S.

1987-01-01

Eighteen tumors of the pineal region were treated at Thomas Jefferson University Hospital since 1957. Preoperative evaluation included CT scan in 11 patients and cerebrospinal fluid cytology in four. Histologic diagnosis was obtained in nine patients. Diagnosis in two other patients was based on CT scan response at 2,000 cGY. Fifteen patients received whole-brain irradiation with a boost, one each with limited-field and whole-brain irradiation only. One patient with melanoma received craniospinal irradiation. Median pineal dose was 55 Gy; range, 50-60 Gy. Five treatment failures occurred, four local and one distant. Actuarial survival was 80%, 70%, and 65% at 5, 10, and 20 years. Median follow-up was 8.8 years. Cranial radiotherapy alone appears to control the majority of pineal tumors

High performance proton accelerators

International Nuclear Information System (INIS)

Favale, A.J.

1989-01-01

In concert with this theme this paper briefly outlines how Grumman, over the past 4 years, has evolved from a company that designed and fabricated a Radio Frequency Quadrupole (RFQ) accelerator from the Los Alamos National Laboratory (LANL) physics and specifications to a company who, as prime contractor, is designing, fabricating, assembling and commissioning the US Army Strategic Defense Commands (USA SDC) Continuous Wave Deuterium Demonstrator (CWDD) accelerator as a turn-key operation. In the case of the RFQ, LANL scientists performed the physics analysis, established the specifications supported Grumman on the mechanical design, conducted the RFQ tuning and tested the RFQ at their laboratory. For the CWDD Program Grumman has the responsibility for the physics and engineering designs, assembly, testing and commissioning albeit with the support of consultants from LANL, Lawrence Berkeley Laboratory (LBL) and Brookhaven National laboratory. In addition, Culham Laboratory and LANL are team members on CWDD. LANL scientists have reviewed the physics design as well as a USA SDC review board. 9 figs

Technical committee on review of national programmes on fast reactors and accelerator driven systems (ADS). Working material

International Nuclear Information System (INIS)

2001-01-01

The objectives of the meeting were: to exchange information on the national programmes on fast reactors (FR) and accelerator driven systems (ADS); to review the progress since the previous IWG-FR meeting, including the status of the actions; to consider meeting arrangements for 2001 and 2002; to review the Agency co-ordinated research activities in the field of FR and ADS, as well as so-ordination of the TWG-FR activities with their organisations. This report covers the reports presented on the relevant activities in Brazil, China, France, Germany, India, Italy, Japan, Kazakhstan, Republic of Korea, Russia, Sweden, United Kingdom and USA

TL dosimetry in the new Tandetron ion accelerator site of the National Institute of Nuclear Research (ININ); Dosimetria TL en el area del nuevo acelerador de iones Tandetron del ININ

Energy Technology Data Exchange (ETDEWEB)

Valdovinos A, M.; Gonzalez M, P.R. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

2000-07-01

The National Institute of Nuclear Research (ININ) acquired a positive ions accelerator type Tandetron 2 MV of the dutch company High Voltage Engineering, Europe B.V., which was finished its installation this year (2000) in an already existing building in the Dr. Nabor Carrillo Flores Nuclear Centre, where it was prepared for the following purposes: the accelerator will be used to realize research through X-ray emission induced by charged particles, Rutherford backscattering analysis, nuclear reaction analysis, gamma ray emission induced by charged particles, resonant dispersion analysis, elastic backward detection analysis and by particle canalization analysis. The accelerator consists of an injection system with two ion sources, ion accelerator tank with voltage in terminal at 2 MV, recovery and recirculation system of charge interchange gas, iman selector analyzer system and with high energy focussing, control system through computer and management and recovery of isolator gas system. For the realization of operation tests of this accelerator, it was had the license authorizing by the National Commission of Nuclear Safety and Safeguards (CNSNS). During the test stage Tl dosemeters were arranged in the Tandetron accelerator area, and also in direction to the beam outlet. In this work, are presented the obtained results of the measurement of radiation levels, as in the area as in the beam outlet. (Author)

BEAM EMITTANCE MEASUREMENT TOOL FOR CEBAF OPERATIONS

International Nuclear Information System (INIS)

Chevtsov, Pavel; Tiefenback, Michael

2008-01-01

A new software tool was created at Jefferson Lab to measure the emittance of the CEBAF electron beams. The tool consists of device control and data analysis applications. The device control application handles the work of wire scanners and writes their measurement results as well as the information about accelerator settings during these measurements into wire scanner data files. The data analysis application reads these files and calculates the beam emittance on the basis of a wire scanner data processing model. Both applications are computer platform independent but are mostly used on LINUX PCs recently installed in the accelerator control room. The new tool significantly simplifies beam emittance measurement procedures for accelerator operations and contributes to a very high availability of the CEBAF machine for the nuclear physics program at Jefferson Lab.

Theoretical and numerical study of the acceleration of particles in the separated sector cyclotrons (SSC's) at the large national heavy ion accelerator (GANIL)

International Nuclear Information System (INIS)

Chabert, A.; Gendreau, G.; Sauret, J.; Cardin, L.

The ideal machine is first considered, and the following topics are covered: (1) characteristics of accelerator cavities; (2) flat-topping; (3) the traverse of one acceleration interval; (4) the energy gain during the crossing of a cavity; and (5) beam injection conditions. A study is given of the coupling, including space charge forces, phase compression, and the effect of the angular opening of the accelerator cavities. The tolerances on the beam injection parameters and on the accelerator system are discussed

Hadrons accelerators in the cancer therapy

International Nuclear Information System (INIS)

Amaldi, U.; Silari, M.

1998-01-01

The use of hadrons accelerators ( protons and light ions) in the cancer therapy is tackled. After shorts introductory words about the medical reasons in favour of using charged heavy particles radiotherapy, an overall idea is given on the accelerators technology and on the guiding and focusing systems. The Italian project of hadron-therapy (the most important project of this kind in Europe) is introduced, with in reference the National Oncological Center of Hadron-therapy and the plans of two kinds of compact protons accelerators in order to introduce the therapy with protons in a great number of hospitals. Finally, the needs in radiation protection are discussed. (N.C.)

76 FR 64960 - Federal Radiological Preparedness Coordinating Committee

Science.gov (United States)

2011-10-19

... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency [Docket ID FEMA-2010-0032... Radisson Hotel Reagan National Airport in Salons I, II and III at 2020 Jefferson Davis Highway, Arlington... Radisson Hotel Reagan National Airport in Salons I, II and III at 2020 Jefferson Davis Highway, Arlington...

Pulsed power accelerators for particle beam fusion

International Nuclear Information System (INIS)

Martin, T.H.; Barr, G.W.; VanDevender, J.P.; White, R.A.; Johnson, D.L.

1980-01-01

Sandia National Laboratories is completing the construction phase of the Particle Beam Fusion Accelerator-I (PBFA-I). Testing of the 36 module, 30 TW, 1 MJ output accelerator is in the initial stages. The 4 MJ, PBFA Marx generator has provided 3.6 MA into water-copper sulfate load resistors with a spread from first to last Marx firing between 15 to 25 ns and an output power of 5.7 TW. This accelerator is a modular, lower voltage, pulsed power device that is capable of scaling to power levels exceeding 100 TW. The elements of the PBFA technology and their integration into an accelerator system for particle beam fusion will be discussed

ORNL pellet acceleration program

International Nuclear Information System (INIS)

Foster, C.A.; Milora, S.L.

1978-01-01

The Oak Ridge National Laboratory (ORNL) pellet fueling program is centered around developing equipment to accelerate large pellets of solidified hydrogen to high speeds. This equipment will be used to experimentally determine pellet-plasma interaction physics on contemporary tokamaks. The pellet experiments performed on the Oak Ridge Tokamak (ORMAK) indicated that much larger, faster pellets would be advantageous. In order to produce and accelerate pellets of the order of 1 to 6 mm in diameter, two apparatuses have been designed and are being constructed. The first will make H 2 pellets by extruding a filament of hydrogen and mechanically chopping it into pellets. The pellets formed will be mechanically accelerated with a high speed arbor to a speed of 950 m/sec. This technique may be extended to speeds up to 5000 m/sec, which makes it a prime candidate for a reactor fueling device. In the second technique, a hydrogen pellet will be formed, loaded into a miniature rifle, and accelerated by means of high pressure hydrogen gas. This technique should be capable of speeds of the order of 1000 m/sec. While this technique does not offer the high performance of the mechanical accelerator, its relative simplicity makes it attractive for near-term experiments

Experiment E89-044 on the Quasielastic ³He(e,e'p) Reaction at Jefferson Laboratory

Energy Technology Data Exchange (ETDEWEB)

Penel-Nottaris, Emilie [Univ. Joseph Fourier Grenoble (France)

2004-07-07

The Jefferson Lab Hall A E89-044 experiment has measured the ³He(e,e'p) reaction cross-sections. The extraction of the longitudinal and transverse response functions for the two-body break-up ³He(e,e'p)d reaction in parallel kinematics allows the study of the bound proton electromagnetic properties inside the ³He nucleus and the involved nuclear mechanisms beyond plane wave approximations.

Accelerator R and D: Research for Science - Science for Society

International Nuclear Information System (INIS)

Holtkamp, N.R.; Biedron, S.; Milton, S.V.; Boeh, L.; Clayton, J.E.; Zdasiuk, G.; Gourlay, S.A.; Zisman, M.S.; Hamm, R.W.; Henderson, S.; Hoffstaetter, G.H.; Merminga, L.; Ozaki, S.; Pilat, F.C.; White, M.

2012-01-01

In September 2011 the US Senate Appropriations Committee requested a ten-year strategic plan from the Department of Energy (DOE) that would describe how accelerator R and D today could advance applications directly relevant to society. Based on the 2009 workshop 'Accelerators for America's Future' an assessment was made on how accelerator technology developed by the nation's laboratories and universities could directly translate into a competitive strength for industrial partners and a variety of government agencies in the research, defense and national security sectors. The Office of High Energy Physics, traditionally the steward for advanced accelerator R and D within DOE, commissioned a task force under its auspices to generate and compile ideas on how best to implement strategies that would help fulfill the needs of industry and other agencies, while maintaining focus on its core mission of fundamental science investigation.

Argonne National Laboratory Physics Division annual report, January--December 1996

International Nuclear Information System (INIS)

Thayer, K.J.

1997-08-01

The past year has seen several of the Physics Division's new research projects reach major milestones with first successful experiments and results: the atomic physics station in the Basic Energy Sciences Research Center at the Argonne Advanced Photon Source was used in first high-energy, high-brilliance x-ray studies in atomic and molecular physics; the Short Orbit Spectrometer in Hall C at the Thomas Jefferson National Accelerator (TJNAF) Facility that the Argonne medium energy nuclear physics group was responsible for, was used extensively in the first round of experiments at TJNAF; at ATLAS, several new beams of radioactive isotopes were developed and used in studies of nuclear physics and nuclear astrophysics; the new ECR ion source at ATLAS was completed and first commissioning tests indicate excellent performance characteristics; Quantum Monte Carlo calculations of mass-8 nuclei were performed for the first time with realistic nucleon-nucleon interactions using state-of-the-art computers, including Argonne's massively parallel IBM SP. At the same time other future projects are well under way: preparations for the move of Gammasphere to ATLAS in September 1997 have progressed as planned. These new efforts are imbedded in, or flowing from, the vibrant ongoing research program described in some detail in this report: nuclear structure and reactions with heavy ions; measurements of reactions of astrophysical interest; studies of nucleon and sub-nucleon structures using leptonic probes at intermediate and high energies; atomic and molecular structure with high-energy x-rays. The experimental efforts are being complemented with efforts in theory, from QCD to nucleon-meson systems to structure and reactions of nuclei. Finally, the operation of ATLAS as a national users facility has achieved a new milestone, with 5,800 hours beam on target for experiments during the past fiscal year

Argonne National Laboratory Physics Division annual report, January--December 1996

Energy Technology Data Exchange (ETDEWEB)

Thayer, K.J. [ed.

1997-08-01

The past year has seen several of the Physics Division`s new research projects reach major milestones with first successful experiments and results: the atomic physics station in the Basic Energy Sciences Research Center at the Argonne Advanced Photon Source was used in first high-energy, high-brilliance x-ray studies in atomic and molecular physics; the Short Orbit Spectrometer in Hall C at the Thomas Jefferson National Accelerator (TJNAF) Facility that the Argonne medium energy nuclear physics group was responsible for, was used extensively in the first round of experiments at TJNAF; at ATLAS, several new beams of radioactive isotopes were developed and used in studies of nuclear physics and nuclear astrophysics; the new ECR ion source at ATLAS was completed and first commissioning tests indicate excellent performance characteristics; Quantum Monte Carlo calculations of mass-8 nuclei were performed for the first time with realistic nucleon-nucleon interactions using state-of-the-art computers, including Argonne`s massively parallel IBM SP. At the same time other future projects are well under way: preparations for the move of Gammasphere to ATLAS in September 1997 have progressed as planned. These new efforts are imbedded in, or flowing from, the vibrant ongoing research program described in some detail in this report: nuclear structure and reactions with heavy ions; measurements of reactions of astrophysical interest; studies of nucleon and sub-nucleon structures using leptonic probes at intermediate and high energies; atomic and molecular structure with high-energy x-rays. The experimental efforts are being complemented with efforts in theory, from QCD to nucleon-meson systems to structure and reactions of nuclei. Finally, the operation of ATLAS as a national users facility has achieved a new milestone, with 5,800 hours beam on target for experiments during the past fiscal year.

Improved voltage performance of the Oak Ridge 25URC tandem accelerator

International Nuclear Information System (INIS)

Meigs, M.J.; Jones, C.M.; Haynes, D.L.; Juras, R.C.; Ziegler, N.F.; Roatz, J.E.; Rathmell, R.D.

1989-01-01

This paper reports on the Oak Ridge 25URC tandem electrostatic accelerator one of two accelerators operated by the Holifield Heavy Ion Research Facility (HHIRF) at the Oak Ridge National Laboratory. Placed into routine service in 1982, the accelerator has provided a wide range of heavy ion beams for research in nuclear and atomic physics. These beams have been provided both directly and after further acceleration by the Oak Ridge Isochronous Cyclotron (ORIC). Show schematically in this paper, the tandem accelerator is a model 25URC Pelletron accelerator

Jefferson Teamwork Observation Guide (JTOG): An Instrument to Observe Teamwork Behaviors.

Science.gov (United States)

Lyons, Kevin J; Giordano, Carolyn; Speakman, Elizabeth; Smith, Kellie; Horowitz, June A

2016-01-01

Interprofessional education (IPE) is becoming an integral part of the education of health professions students. However, teaching students to become successful members of interprofessional teams is complex, and it is important for students to learn the combinations of skills necessary for teams to function effectively. There are many instruments available to measure many features related to IPE. However, these instruments are often too cumbersome to use in an observational situation since they tend to be lengthy and contain many abstract characteristics that are difficult to identify. The Jefferson Teamwork Observation Guide (JTOG) is a short tool that was created for students early in their educational program to observe teams in action with a set of guidelines to help them focus their observation on behaviors indicative of good teamwork. The JTOG was developed over a 2-year period based on student and clinician feedback and the input of experts in IPE. While initially developed as a purely educational tool for prelicensure students, it is becoming clear that it is an easy-to-use instrument that assesses the behavior of clinicians in practice.

The cryogenic target for the G0 experiment at Jefferson lab

International Nuclear Information System (INIS)

Covrig, S.D.; Beise, E.J.; Carr, R.; Gustafsson, K.K.; Hannelius, L.; Herda, M.-C.; Jones, C.E.; Liu, J.; McKeown, R.D.; Neveling, R.; Rauf, A.W.; Smith, G.

2005-01-01

A cryogenic horizontal single loop target has been designed, built, tested and operated for the G 0 experiment in Hall C at Jefferson Lab. The target cell is 20cm long, the loop volume is 6.5l and the target operates with the cryogenic pump fully immersed in the fluid. The target has been designed to operate at 30Hz rotational pump speed with either liquid hydrogen or liquid deuterium. The high-power heat exchanger is able to remove 1000W of heat from the liquid hydrogen, while the nominal electron beam with current of 40μA and energy of 3GeV deposits about 320W of heat into the liquid. The increase in the systematic uncertainty due to the liquid hydrogen target is negligible on the scale of a parity violation experiment. The global normalized yield reduction for 40μA beam is about 1.5% and the target density fluctuations contribute less than 238ppm (parts per million) to the total asymmetry width, typically about 1200ppm, in a Q 2 bin

Electron Ion Collider: The Next QCD Frontier - Understanding the glue that binds us all

CERN Document Server

Accardi, A.; Anselmino, M.; Armesto, N.; Aschenauer, E.C.; Bacchetta, A.; Boer, D.; Brooks, W.K.; Burton, T.; Chang, N.B.; Deng, W.T.; Deshpande, A.; Diehl, M.; Dumitru, A.; Dupré, R.; Ent, R.; Fazio, S.; Gao, H.; Guzey, V.; Hakobyan, H.; Hao, Y.; Hasch, D.; Holt, R.; Horn, T.; Huang, M.; Hutton, A.; Hyde, C.; Jalilian-Marian, J.; Klein, S.; Kopeliovich, B.; Kovchegov, Y.; Kumar, K.; Kumerički, K.; Lamont, M.A.C.; Lappi, T.; Lee, J.H.; Lee, Y.; Levin, E.M.; Lin, F.L.; Litvinenko, V.; Ludlam, T.W.; Marquet, C.; Meziani, Z.E.; McKeown, R.; Metz, A.; Milner, R.; Morozov, V.S.; Mueller, A.H.; Müller, B.; Müller, Dieter; Nadel-Turonski, P.; Paukkunen, H.; Prokudin, A.; Ptitsyn, V.; Qian, X.; Qiu, J.W.; Ramsey-Musolf, M.; Roser, T.; Sabatié, F.; Sassot, R.; Schnell, G.; Schweitzer, P.; Sichtermann, E.; Stratmann, M.; Strikman, M.; Sullivan, M.; Taneja, S.; Toll, T.; Trbojevic, D.; Ullrich, T.; Venugopalan, R.; Vigdor, S.; Vogelsang, W.; Weiss, C.; Xiao, B.W.; Yuan, F.; Zhang, Y.H.; Zheng, L.

2016-01-01

This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics and, in particular, the focused ten-week program on "Gluons and quark sea at high energies" at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them, and it benefited from inputs from the users' communities of BNL and JLab. This White Paper offers the promise to prope...

ELECTRON COOLING FOR RHIC

International Nuclear Information System (INIS)

Ben-Zvi, I.

2001-01-01

The Accelerator Collider Department (CAD) at Brookhaven National Laboratory is operating the Relativistic Heavy Ion Collider (RHIC), which includes the dual-ring, 3.834 km circumference superconducting collider and the venerable AGS as the last part of the RHIC injection chain. CAD is planning on a luminosity upgrade of the machine under the designation RHIC II. One important component of the RHIC II upgrade is electron cooling of RHIC gold ion beams. For this purpose, BNL and the Budker Institute of Nuclear Physics in Novosibirsk entered into a collaboration aimed initially at the development of the electron cooling conceptual design, resolution of technical issues, and finally extend the collaboration towards the construction and commissioning of the cooler. Many of the results presented in this paper are derived from the Electron Cooling for RHIC Design Report [1], produced by the, BINP team within the framework of this collaboration. BNL is also collaborating with Fermi National Laboratory, Thomas Jefferson National Accelerator Facility and the University of Indiana on various aspects of electron cooling

ELECTRON COOLING FOR RHIC.

Energy Technology Data Exchange (ETDEWEB)

BEN-ZVI,I.

2001-05-13

The Accelerator Collider Department (CAD) at Brookhaven National Laboratory is operating the Relativistic Heavy Ion Collider (RHIC), which includes the dual-ring, 3.834 km circumference superconducting collider and the venerable AGS as the last part of the RHIC injection chain. CAD is planning on a luminosity upgrade of the machine under the designation RHIC II. One important component of the RHIC II upgrade is electron cooling of RHIC gold ion beams. For this purpose, BNL and the Budker Institute of Nuclear Physics in Novosibirsk entered into a collaboration aimed initially at the development of the electron cooling conceptual design, resolution of technical issues, and finally extend the collaboration towards the construction and commissioning of the cooler. Many of the results presented in this paper are derived from the Electron Cooling for RHIC Design Report [1], produced by the, BINP team within the framework of this collaboration. BNL is also collaborating with Fermi National Laboratory, Thomas Jefferson National Accelerator Facility and the University of Indiana on various aspects of electron cooling.

Future Measurements of the Nucleon Elastic Electromagnetic Form Factors at Jefferson Lab

Science.gov (United States)

Gilfoyle, Gerard

2018-01-01

The elastic, electromagnetic form factors are fundamental observables that describe the internal structure of protons, neutrons, and atomic nuclei. Jefferson Lab in the United States has completed the 12 GeV Upgrade that will open new opportunities to study the form factors. A campaign to measure all four nucleon form factors (electric and magnetic ones for both proton and neutron) has been approved consisting of seven experiments in Halls A, B, and C. The increased energy of the electron beam will extend the range of precision measurements to higher Q2 for all four form factors together. This combination of measurements will allow for the decomposition of the results into their quark components and guide the development of a QCD-based understanding of nuclei in the non-perturbative regime. I will present more details on the 12 GeV Upgrade, the methods used to measure the form factors, and what we may learn.

Workshop on the accelerator for particle therapy

International Nuclear Information System (INIS)

Inoue, M.; Ujeno, Y.

1991-02-01

A two-day workshop on the accelerator for particle therapy was held on August 22-23, 1990, with the aim of mutual understanding of medical accelerators among investigators. The state-of-the-art facilities in Japan and medical proton accelerators in Japan and other countries were introduced. This is a compilation of papers presented at the workshop: (1) particle radiotherapy at the National Institute of Radiological Sciences (NIRS); (2) proton therapy; (3) treatment planning, especially for photon and electron therapies; (4) heavy ion synchrotron project at the NIRS; (5) medical proton accelerator project of Tsukuba University and recent status of Loma Linda University Medical Center Proton Beam Facility; (6) inspection report on the Loma Linda University Medical Center Proton Beam Facility; (7) accelerator project of Kyoto University; (8) actual conditions of the 7 MeV proton linear accelerator; (9) design study of superconducting compact cyclotron prototype model; (10) medical superconducting prototype cyclotron; (11) RCNP cyclotron cascade project; (12) beam extraction from synchrotron; (13) radiation safety design in high energy particle accelerator facilities. (N.K.)

Advanced Accelerator Test Facility (AATF) upgrade plan

International Nuclear Information System (INIS)

Gai, W.; Ho, C.; Konecny, R.

1989-01-01

We have successfully demonstrated the principles of wake-field acceleration using structures (cavity, dielectric) and plasmas as wake-field devices using the AATF at Argonne National Laboratory. Due to the limited driver electron pulse intensity and relative long pulse length, only modest accelerating gradients were observed. In order to study the wake field effects in much greater detail and demonstrate the feasibility of wake-field accelerator for high energy physics, we are considering construction of a laser photocathode injector on the existing 20 MeV Chem-Linac to produce very intense and short electron pulses. 10 refs., 5 figs

The G0 experiment at Jefferson laboratory: Measurement of the weak neutral form factors of the nucleon

International Nuclear Information System (INIS)

Furget, C.

2005-01-01

The G0 experiment aims to measure parity-violating asymmetries in elastic electron-proton and quasi-elastic electron-deuteron scattering. This experimental program allows to perform the separation of the electric and magnetic weak neutral and axial form factors for three different momentum transfers 0.3, 0.5 and 0.8 (GeV/c)2. The first part of the experiment has been performed in Hall C of Jefferson Laboratory with a commissioned setup. A preliminary analysis of the data has provided a first estimate of the main systematic uncertainties. The analysis to determine the actual physics asymmetries is proceeding

Recirculating accelerator driver for a high-power free-electron laser: A design overview

International Nuclear Information System (INIS)

Bohn, C.L.

1997-01-01

Jefferson Lab is building a free-electron laser (FEL) to produce continuous-wave (cw), kW-level light at 3-6 μm wavelength. A superconducting linac will drive the laser, generating a 5 mA average current, 42 MeV energy electron beam. A transport lattice will recirculate the beam back to the linac for deceleration and conversion of about 75% of its power into rf power. Bunch charge will range up to 135 pC, and bunch lengths will range down to 1 ps in parts of the transport lattice. Accordingly, space charge in the injector and coherent synchrotron radiation in magnetic bends come into play. The machine will thus enable studying these phenomena as a precursor to designing compact accelerators of high-brightness beams. The FEL is scheduled to be installed in its own facility by 1 October 1997. Given the short schedule, the machine design is conservative, based on modifications of the CEBAF cryomodule and MIT-Bates transport lattice. This paper surveys the machine design

Recirculating accelerator driver for a high-power free-electron laser: A design overview

Energy Technology Data Exchange (ETDEWEB)

Bohn, C.L. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

1997-06-01

Jefferson Lab is building a free-electron laser (FEL) to produce continuous-wave (cw), kW-level light at 3-6 {mu}m wavelength. A superconducting linac will drive the laser, generating a 5 mA average current, 42 MeV energy electron beam. A transport lattice will recirculate the beam back to the linac for deceleration and conversion of about 75% of its power into rf power. Bunch charge will range up to 135 pC, and bunch lengths will range down to 1 ps in parts of the transport lattice. Accordingly, space charge in the injector and coherent synchrotron radiation in magnetic bends come into play. The machine will thus enable studying these phenomena as a precursor to designing compact accelerators of high-brightness beams. The FEL is scheduled to be installed in its own facility by 1 October 1997. Given the short schedule, the machine design is conservative, based on modifications of the CEBAF cryomodule and MIT-Bates transport lattice. This paper surveys the machine design.

rf quadrupole linac: a new low-energy accelerator

International Nuclear Information System (INIS)

Hamm, R.W.; Crandall, K.R.; Fuller, C.W.

1980-01-01

A new concept in low-energy particle accelerators, the radio-frequency quadrupole (RFQ) linac, is currently being developed at the Los Alamos National Scientific Laboratory. In this new linear accelerating structure both the focusing and accelerating forces are produced by the rf fields. It can accept a high-current, low-velocity dc ion beam and bunch it with a high capture efficiency. The performance of this structure as a low-energy linear accelerator has been verified with the successful construction of a proton RFQ linac. This test structure has accelerated 38 mA of protons from 100 keV to 640 keV in 1.1 meters with a capture efficiency greater than 80%. In this paper a general description of the RFQ linac and an outline of the basic RFQ linac design procedure are presented in addition to the experimental results from the test accelerator. Finally, several applications of this new accelerator are discussed

Development of a Metacognitive Effort Construct of Empathy during Clinical Training: A Longitudinal Study of the Factor Structure of the Jefferson Scale of Empathy

Science.gov (United States)

Stansfield, R. Brent; Schwartz, Alan; O'Brien, Celia Laird; Dekhtyar, Michael; Dunham, Lisette; Quirk, Mark

2016-01-01

Empathy is crucial for effective clinical care but appears to decline during undergraduate medical training. Understanding the nature of this decline is necessary for addressing it. The Jefferson Scale of Empathy (JSE) is used to measure medical students' clinical empathy attitudes. One recent study described a 3-factor model of the JSE. This…

Eleven Years of Data on the Jefferson Scale of Empathy-Medical Student Version (JSE-S): Proxy Norm Data and Tentative Cutoff Scores.

Science.gov (United States)

Hojat, Mohammadreza; Gonnella, Joseph S

2015-01-01

This study was designed to provide typical descriptive statistics, score distributions and percentile ranks of the Jefferson Scale of Empathy-Medical Student version (JSE-S) of male and female medical school matriculants to serve as proxy norm data and tentative cutoff scores. The participants were 2,637 students (1,336 women and 1,301 men) who matriculated at Sidney Kimmel (formerly Jefferson) Medical College between 2002 and 2012, and completed the JSE at the beginning of medical school. Information extracted from descriptive statistics, score distributions and percentile ranks for male and female matriculants were used to develop proxy norm data and tentative cutoff scores. The score distributions of the JSE tended to be moderately skewed and platykurtic. Women obtained a significantly higher mean score (116.2 ± 9.7) than men (112.3 ± 10.8) on the JSE-S (t2,635 = 9.9, p norm data. The tentative cutoff score to identify low scorers was ≤ 95 for men and ≤ 100 for women. Our findings provide norm data and cutoff scores for admission decisions under certain conditions and for identifying students in need of enhancing their empathy. © 2015 S. Karger AG, Basel.

12th Advanced Accelerator Concept (AAC 2006) Workshop

International Nuclear Information System (INIS)

Piot, Philippe

2006-01-01

Summary of the 12th Advanced Accelerator Concept (AAC 2006) Workshop help by NIU and ANL on July 10th-15th 2006 in Lake Geneva WI. The proceedings of the workshop have been published as an AIP conference proceedings '12th Advanced Accelerator Concepts Workshop' volume 877. The Twelfth Workshop on Advanced Accelerator Concepts was held at the Grand Geneva Resort in Lake Geneva, Wisconsin, from July 10 to July 15, 2006. The Workshop was sponsored by the High Energy Physics program of the U.S. Department of Energy, and was hosted by the Argonne Wakefield Accelerator Group (AWA) of Argonne National Laboratory and by Northern Illinois University. The workshop is a bi-annual meeting among physicist working on novel charged particle acceleration concept. The name 'advanced accelerator' physics covers long term research and development in beam physics and accelerator technologies. Some of the topics in advanced accelerator R and D are laser acceleration of electrons, wake field acceleration, novel high power rf source, new beam diagnostics, free-electron lasers, generating high brightness electron beams etc. The Advanced Accelerator Concept workshop is the only acknowledged and fully sponsored forum that provides a platform for inter- and cross-disciplinary discussion on various aspects of advanced accelerator and beam physics/technology concepts.

CERN accelerator school: an introductory course in Poland

CERN Multimedia

2006-01-01

For the first time since the CERN Accelerator School (CAS) was set up, the â€ﾜIntroduction to Accelerator Physics” course was held in Zakopane, Poland.  This course was organised together with the National Atomic Energy Agency, Warsaw and the AGH University of Science and Technology, Cracow and was held from 1-13 October 2006 at the foot of the Tatra Mountains. The course was very well attended with 113 participants representing 26 different nationalities. Although most of the participants originated from Europe, some students came from countries as far away as Canada, China, India and North America.

Inverse Free Electron Laser accelerator

International Nuclear Information System (INIS)

Fisher, A.; Gallardo, J.; van Steenbergen, A.; Sandweiss, J.

1992-09-01

The study of the INVERSE FREE ELECTRON LASER, as a potential mode of electron acceleration, is being pursued at Brookhaven National Laboratory. Recent studies have focussed on the development of a low energy, high gradient, multi stage linear accelerator. The elementary ingredients for the IFEL interaction are the 50 MeV Linac e - beam and the 10 11 Watt CO 2 laser beam of BNL's Accelerator Test Facility (ATF), Center for Accelerator Physics (CAP) and a wiggler. The latter element is designed as a fast excitation unit making use of alternating stacks of Vanadium Permendur (VaP) ferromagnetic laminations, periodically interspersed with conductive, nonmagnetic laminations, which act as eddy current induced field reflectors. Wiggler parameters and field distribution data will be presented for a prototype wiggler in a constant period and in a ∼ 1.5 %/cm tapered period configuration. The CO 2 laser beam will be transported through the IFEL interaction region by means of a low loss, dielectric coated, rectangular waveguide. Short waveguide test sections have been constructed and have been tested using a low power cw CO 2 laser. Preliminary results of guide attenuation and mode selectivity will be given, together with a discussion of the optical issues for the IFEL accelerator. The IFEL design is supported by the development and use of 1D and 3D simulation programs. The results of simulation computations, including also wiggler errors, for a single module accelerator and for a multi-module accelerator will be presented

Exploring QCD dynamics in medium energy γA semiexclusive collisions

Directory of Open Access Journals (Sweden)

A.B. Larionov

2016-09-01

Full Text Available We demonstrate that studies of the semiexclusive large angle photon–nucleus reactions: γ+A→h1+h2+(A−1⁎ with tagged photon beams of energies 6÷10 GeV which can be performed in Hall D at Thomas Jefferson National Acceleration Facility (TJNAF would allow to probe several aspects of the QCD dynamics: establish the t-range in which transition from soft to hard dynamics occurs, compare the strength of the interaction of various mesons and baryons with nucleons at the energies of few GeV, as well as look for the color transparency effects.

Neutron electric form factor via recoil polarimetry

International Nuclear Information System (INIS)

Richard Madey; Andrei Semenov; Simon Taylor; Aram Aghalaryan; Erick Crouse; Glen MacLachlan; Bradley Plaster; Shigeyuki Tajima; William Tireman; Chenyu Yan; Abdellah Ahmidouch; Brian Anderson; Razmik Asaturyan; O. Baker; Alan Baldwin; Herbert Breuer; Roger Carlini; Michael Christy; Steve Churchwell; Leon Cole; Samuel Danagoulian; Donal Day; Mostafa Elaasar; Rolf Ent; Manouchehr Farkhondeh; Howard Fenker; John Finn; Liping Gan; Kenneth Garrow; Paul Gueye; Calvin Howell; Bitao Hu; Mark Jones; James Kelly; Cynthia Keppel; Mahbubul Khandaker; Wooyoung Kim; Stanley Kowalski; Allison Lung; David Mack; D. Manley; Pete Markowitz; Joseph Mitchell; Hamlet Mkrtchyan; Allena Opper; Charles Perdrisat; Vina Punjabi; Brian Raue; Tilmann Reichelt; Joerg Reinhold; Julie Roche; Yoshinori Sato; Wonick Seo; Neven Simicevic; Gregory Smith; Samuel Stepanyan; Vardan Tadevosyan; Liguang Tang; Paul Ulmer; William Vulcan; John Watson; Steven Wells; Frank Wesselmann; Stephen Wood; Chen Yan; Seunghoon Yang; Lulin Yuan; Wei-Ming Zhang; Hong Guo Zhu; Xiaofeng Zhu

2003-01-01

The ratio of the electric to the magnetic form factor of the neutron, G En /G Mn , was measured via recoil polarimetry from the quasielastic d((pol-e),e(prime)(pol-n)p) reaction at three values of Q 2 [viz., 0.45, 1.15 and 1.47 (GeV/c) 2 ] in Hall C of the Thomas Jefferson National Accelerator Facility. Preliminary data indicate that G En follows the Galster parameterization up to Q 2 = 1.15 (GeV/c) 2 and appears to rise above the Galster parameterization at Q 2 = 1.47 (GeV/c) 2

Magnetic Measurement of the 10 kW, IR FEL Dipole Magnets

International Nuclear Information System (INIS)

Tommy Hiatt; Kenneth Baggett; J. Beck; George Biallas; David Douglas; Kevin Sullivan; C. Tennant

2003-01-01

Magnetic measurements have been performed on several families of dipoles for the 10 kW IR-FEL presently under construction at the Thomas Jefferson National Accelerator Facility. The requirements for these magnets include varying field strengths, large horizontal apertures and parts in 10,000 field homogeneity as well as setability of core and integrated field. Measurements were made to quantify the magnets according to these requirements and to determine the hysteresis protocol, ramp rate dependence, and field clamp settings that are used. This paper will describe the results of these measurements and the procedures used to accomplish them

Precise measurements of beam spin asymmetries in semi-inclusive π0 production

Science.gov (United States)

Aghasyan, M.; Avakian, H.; Rossi, P.; De Sanctis, E.; Hasch, D.; Mirazita, M.; Adikaram, D.; Amaryan, M. J.; Anghinolfi, M.; Baghdasaryan, H.; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Bennett, R. P.; Biselli, A. S.; Branford, D.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Carman, D. S.; Chandavar, S.; Cole, P. L.; Collins, P.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Daniel, A.; Dashyan, N.; De Vita, R.; Deur, A.; Dey, B.; Dickson, R.; Djalali, C.; Dodge, G. E.; Doughty, D.; Dupre, R.; Egiyan, H.; El Alaoui, A.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fradi, A.; Gabrielyan, M. Y.; Garçon, M.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Graham, L.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Guler, N.; Guo, L.; Hafidi, K.; Hanretty, C.; Hicks, K.; Holtrop, M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Isupov, E. L.; Jawalkar, S. S.; Jenkins, D.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Khetarpal, P.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuhn, S. E.; Kuleshov, S. V.; Kuznetsov, V.; Kvaltine, N. D.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McAndrew, J.; McKinnon, B.; Meyer, C. A.; Micherdzinska, A. M.; Mokeev, V.; Moreno, B.; Moutarde, H.; Munevar, E.; Nadel-Turonski, P.; Ni, A.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Pappalardo, L.; Paremuzyan, R.; Park, K.; Park, S.; Pasyuk, E.; Pereira, S. Anefalos; Phelps, E.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Raue, B. A.; Ricco, G.; Rimal, D.; Ripani, M.; Rosner, G.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Seraydaryan, H.; Sharabian, Y. G.; Smith, G. D.; Sober, D. I.; Stepanyan, S. S.; Stepanyan, S.; Stoler, P.; Strakovsky, I.; Strauch, S.; Taiuti, M.; Tang, W.; Taylor, C. E.; Tkachenko, S.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Watts, D.; Weinstein, L. B.; Weygand, D. P.; Wood, M. H.; Zana, L.; Zhang, J.; Zhao, B.; Zhao, Z. W.

2011-10-01

We present studies of single-spin asymmetries for neutral pion electroproduction in semi-inclusive deep-inelastic scattering of 5.776 GeV polarized electrons from an unpolarized hydrogen target, using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. A substantial sinϕh amplitude has been measured in the distribution of the cross section asymmetry as a function of the azimuthal angle ϕh of the produced neutral pion. The dependence of this amplitude on Bjorken x and on the pion transverse momentum is extracted with significantly higher precision than previous data and is compared to model calculations.

Accelerated Test Method for Corrosion Protective Coatings

Data.gov (United States)

National Aeronautics and Space Administration — This project seeks to develop a new accelerated corrosion test method that predicts the long-term corrosion protection performance of spaceport structure coatings as...

VLHC accelerator physics

Energy Technology Data Exchange (ETDEWEB)

Michael Blaskiewicz et al.

2001-11-01

A six-month design study for a future high energy hadron collider was initiated by the Fermilab director in October 2000. The request was to study a staged approach where a large circumference tunnel is built that initially would house a low field ({approx}2 T) collider with center-of-mass energy greater than 30 TeV and a peak (initial) luminosity of 10{sup 34} cm{sup -2}s{sup -1}. The tunnel was to be scoped, however, to support a future upgrade to a center-of-mass energy greater than 150 TeV with a peak luminosity of 2 x 10{sup 34} cm{sup -2} sec{sup -1} using high field ({approx} 10 T) superconducting magnet technology. In a collaboration with Brookhaven National Laboratory and Lawrence Berkeley National Laboratory, a report of the Design Study was produced by Fermilab in June 2001. 1 The Design Study focused on a Stage 1, 20 x 20 TeV collider using a 2-in-1 transmission line magnet and leads to a Stage 2, 87.5 x 87.5 TeV collider using 10 T Nb{sub 3}Sn magnet technology. The article that follows is a compilation of accelerator physics designs and computational results which contributed to the Design Study. Many of the parameters found in this report evolved during the study, and thus slight differences between this text and the Design Study report can be found. The present text, however, presents the major accelerator physics issues of the Very Large Hadron Collider as examined by the Design Study collaboration and provides a basis for discussion and further studies of VLHC accelerator parameters and design philosophies.

Recent progress in accelerator activities at Raja Ramanna Centre for Advanced Technology, Indore

International Nuclear Information System (INIS)

Gupta, P.D.

2013-01-01

Raja Ramanna Centre for Advanced Technology, Indore is a premier national institute engaged in R and D work in front-line areas of accelerator science, technology, and applications. The Centre has designed, developed, and commissioned two synchrotron radiation sources: Indus-1 and Indus-2, serving as national facilities. The Centre is pursuing various other accelerator activities viz. development of a high energy proton accelerator for a spallation neutron source, electron accelerators for food irradiation and industrial applications and free electron lasers (FEL) in THz and IR spectral region, study of innovative schemes of laser driven electron acceleration, and development of advanced technologies to support these activities such as superconducting RF (SCRF) technology, cryogenics, RF power, magnets, ultra high vacuum and control instrumentation. In this talk, an overview of the progress made in accelerator activities at Raja Ramanna Centre for Advanced Technology in recent years is be presented

The electronic logbook for LNL accelerators

International Nuclear Information System (INIS)

Canella, S.; Carletto, O.

2012-01-01

In spring 2009 all run-time data concerning the particle accelerators at LNL (Legnaro National Laboratory) were still registered mainly on paper. The electrostatic accelerator TANDEM-XTU and its Negative Source data were logged on a large format paper logbook. For the ALPI booster and the PIAVE injector with its Positive ECR Source a number of independent paper notebooks were used, together with plain data files containing raw instant snapshots of the RF super-conductive accelerators. At that time a decision was taken to build a new tool for a general electronic registration of accelerators run-time data. The result of this effort, the LNL electronic logbook, is here presented. The LNL electronic logbook is a many-layers software tool that is made of data sets and software programs. It is used to register states, events, texts, images and files according to the shift structures in the working time of the LNL accelerators. The same system is used to register data and to retrieve them. It may be accessed by standard browser on any platform

Advanced Computing for 21st Century Accelerator Science and Technology

International Nuclear Information System (INIS)

Dragt, Alex J.

2004-01-01

Dr. Dragt of the University of Maryland is one of the Institutional Principal Investigators for the SciDAC Accelerator Modeling Project Advanced Computing for 21st Century Accelerator Science and Technology whose principal investigators are Dr. Kwok Ko (Stanford Linear Accelerator Center) and Dr. Robert Ryne (Lawrence Berkeley National Laboratory). This report covers the activities of Dr. Dragt while at Berkeley during spring 2002 and at Maryland during fall 2003

The Radiological Research Accelerator Facility

International Nuclear Information System (INIS)

Hall, E.J.; Marino, S.A.

1991-05-01

The Radiological Research Accelerator Facility (RARAF) is based on 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) -- formerly the Radiological Research Laboratory (RRL) -- of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). As such, RARAF is available to all potential users on an equal basis, and scientists outside the CRR are encouraged to submit proposals for experiments at RARAF. The operation of the Van de Graaff is supported by the DOE, but the research projects themselves must be supported separately. Brief summaries of research experiments are included. Accelerator usage is summarized and development activities are discussed. 8 refs., 8 tabs

A search for baryon- and lepton-number violating decays of $\\Lambda$ hyperons using the CLAS detector at Jefferson Laboratory

OpenAIRE

McCracken, M. E.; Bellis, M.; Adhikari, K. P.; Adikaram, D.; Akbar, Z.; Pereira, S. Anefalos; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.

2015-01-01

We present a search for ten baryon-number violating decay modes of $\\Lambda$ hyperons using the CLAS detector at Jefferson Laboratory. Nine of these decay modes result in a single meson and single lepton in the final state ($\\Lambda \\rightarrow m \\ell$) and conserve either the sum or the difference of baryon and lepton number ($B \\pm L$). The tenth decay mode ($\\Lambda \\rightarrow \\bar{p}\\pi^+$) represents a difference in baryon number of two units and no difference in lepton number. We obser...

Construction and operation of a 10 MeV electron accelerator and associated experimental facilities at Brookhaven National Laboratory, Upton, New York. Environmental assessment

International Nuclear Information System (INIS)

1994-02-01

The purpose of this environmental impact statement is to determine whether there would be significant environmental impacts associated with the construction of an experimental facility at Brookhaven National Laboratory for radiation chemistry research and operation of the 10-MeV electron accelerator proposed for it. The document describes the need for action, alternative actions, the affected environment, and potential environmental impacts

Accelerator boom hones China's engineering expertise

Science.gov (United States)

Normile, Dennis

2018-02-01

In raising the curtain on the China Spallation Neutron Source, China has joined just four other nations in having mastered the technology of accelerating and controlling beams of protons. The $277 million facility, set to open to users this spring in Dongguan, is expected to yield big dividends in materials science, chemistry, and biology. More world class machines are on the way, as China this year starts construction on four other major accelerator facilities. The building boom is prompting a scramble to find enough engineers and technicians to finish the projects. But if they all come off as planned, the facilities would position China to tackle the next global megaproject: a giant accelerator that would pick up where Europe's Large Hadron Collider leaves off.

Linear accelerator for production of tritium: Physics design challenges

Energy Technology Data Exchange (ETDEWEB)

Wangler, T.P.; Lawrence, G.P.; Bhatia, T.S.; Billen, J.H.; Chan, K.C.D.; Garnett, R.W.; Guy, F.W.; Liska, D.; Nath, S.; Neuschaefer, G.; Shubaly, M.

1990-01-01

In the summer of 1989, a collaboration between Los Alamos National Laboratory and Brookhaven National Laboratory conducted a study to establish a reference design of a facility for accelerator production of tritium (APT). The APT concept is that of a neutron-spallation source, which is based on the use of high-energy protons to bombard lead nuclei, resulting in the production of large quantities of neutrons. Neutrons from the lead are captured by lithium to produce tritium. This paper describes the design of a 1.6-GeV, 250-mA proton cw linear accelerator for APT.

Fermilab and Berkeley Lab Collaborate with Meyer Tool on Key Component for European Particle Accelerator

CERN Multimedia

2004-01-01

Officials of the U.S. Department of Energy's Fermi National Accelerator Laboratory and Lawrence Berkeley National Laboratory announced yesterday the completion of a key component of the U.S. contribution to the Large Hadron Collider, a particle accelerator under construction at CERN, in Geneva, Switzerland

Aerial radiological survey of the Fermi National accelerator Laboratory and surrounding area, Batavia, Illinois. Data of survey: 12-14 May 1977

International Nuclear Information System (INIS)

Jobst, J.E.

1981-01-01

An aerial radiological survey was conducted over the facilities of the Fermi National Accelerator Laboratory (Fermilab) near Batavia, Illinois on 12-14 May 1977. The survey was flown at an altitude of 91 m by a helicopter containing 20 sodium iodide detectors. The line spacing was also 91 m. Enhanced gamma exposure rate levels, which could be attributed to Fermilab operations, were observed at seven locations. One additional anomaly, not related to the Laboratory, was also discovered

A proton medical accelerator by the SBIR route - an example of technology transfer

International Nuclear Information System (INIS)

Martin, R.L.

1989-01-01

Medical facilities for radiation treatment of cancer with protons have been established in many laboratories throughout the world. Essentially all of these have been designed as physics facilities, however, because of the requirement for protons up to 250 MeV. Most of the experience on this branch of accelerator technology lies in the national laboratories and a few large universities. A major issue is the transfer of this technology to the commercial sector to provide hospitals with simple, reliable, and relatively inexpensive accelerators for this application. The author has chosen the SBIR route to accomplish this goal. ACCTEK Associates has received grants from the National Cancer Institute for development of the medical accelerator and beam delivery systems. Considerable encouragement and help has been received from Argonne National Laboratory and the Department of Energy. The experiences to date and the pros and cons on this approach to commercializing medical accelerators are described. (orig.)

A proton medical accelerator by the SBIR route: An example of technology transfer

International Nuclear Information System (INIS)

Martin, R.L.

1988-01-01

Medical facilities for radiation treatment of cancer with protons have been established in many laboratories throughout the world. Essentially all of these have been designed as physics facilities, however, because of the requirement for protons up to 250 MeV. Most of the experience in this branch of accelerator technology lies in the national laboratories and a few large universities. A major issue is the transfer of this technology to the commercial sector to provide hospitals with simple, reliable, and relatively inexpensive accelerators for this application. The author has chosen the SBIR route to accomplish this goal. ACCTEK Associates have received grants from the National Cancer Institute for development of the medical accelerator and beam delivery systems. Considerable encouragement and help has been received from Argonne National Laboratory and the Department of Energy. The experiences to date and the pros and cons on this approach to commercializing medical accelerators are described. 4 refs., 1 fig

The meson spectroscopy program with CLAS12 at Jefferson Laboratory

Energy Technology Data Exchange (ETDEWEB)

Rizzo, Alessandro [Univ. of Rome Tor Vergata (Italy)

2016-06-01

The study of the hadronic spectrum is one of the most powerful tools to investigate the mechanism at the basis of quark confinement within hadrons. A precise determination of the spectrum allows not only to assess the properties of the hadrons in their fundamental and excited states, but also to investigate the existence of states resulting from alternative configurations of quarks and gluons, such as the glue-balls, hybrid hadrons and many-quarks configurations. The study of the mesonic part of the spectrum can play a central role in this investigation thanks to the strong signature that the hybrid mesons are expected to have: the presence of explicit gluonic degrees of freedom in such states may result in JPC configurations not allowed for the standard q ¯ q states. From the experimental side the expected high-multiplicity decays of the hybrid mesons require an apparatus with high performances in terms of rate-capability, resolution and acceptance. The CLAS12 experiment (formally MesonEx) is one of new-generation experiments at Thomas Jefferson National Laboratory (JLAB) for which an unprecedented statistics of events, with fully reconstructed kinematics for large particle multiplicity decays, will be available. A wide scientific program that will start in 2016 has been deployed for meson spectrum investigation with the CLAS12 apparatus in Hall B at energies up to 11 GeV. One of the main parts of the program is based on the use of the Forward Tagger apparatus, which will allow CLAS12 experiment to extend the study of meson electro-production to the quasi-real photo-production kinematical region (very low Q2), where the production of hybrid mesons is expected to be favoured. The data analysis which is required to extract the signal from hybrid states should go beyond the standard partial wave analysis techniques and a new analysis framework is being set up through the international network Haspect. The Haspect Network gathers people involved into theoretical and

Collaboration tools for the global accelerator network Workshop Report

CERN Document Server

Agarwal, D; Olson, J

2002-01-01

The concept of a ''Global Accelerator Network'' (GAN) has been put forward as a means for inter-regional collaboration in the operation of internationally constructed and operated frontier accelerator facilities. A workshop was held to allow representatives of the accelerator community and of the collaboratory development community to meet and discuss collaboration tools for the GAN environment. This workshop, called the Collaboration Tools for the Global Accelerator Network (GAN) Workshop, was held on August 26, 2002 at Lawrence Berkeley National Laboratory. The goal was to provide input about collaboration tools in general and to provide a strawman for the GAN collaborative tools environment. The participants at the workshop represented accelerator physicists, high-energy physicists, operations, technology tool developers, and social scientists that study scientific collaboration.

Collaboration tools for the global accelerator network: Workshop Report

International Nuclear Information System (INIS)

Agarwal, Deborah; Olson, Gary; Olson, Judy

2002-01-01

The concept of a ''Global Accelerator Network'' (GAN) has been put forward as a means for inter-regional collaboration in the operation of internationally constructed and operated frontier accelerator facilities. A workshop was held to allow representatives of the accelerator community and of the collaboratory development community to meet and discuss collaboration tools for the GAN environment. This workshop, called the Collaboration Tools for the Global Accelerator Network (GAN) Workshop, was held on August 26, 2002 at Lawrence Berkeley National Laboratory. The goal was to provide input about collaboration tools in general and to provide a strawman for the GAN collaborative tools environment. The participants at the workshop represented accelerator physicists, high-energy physicists, operations, technology tool developers, and social scientists that study scientific collaboration

Operational experience with synchrotron light interferometers for CEBAF experimental beam lines

Energy Technology Data Exchange (ETDEWEB)

Pavel Chevtsov

2006-10-24

Beam size and energy spread monitoring systems based on Synchrotron Light Interferometers (SLI) have been in operations at Jefferson Lab for several years. A non-invasive nature and a very high (a few mm) resolution of SLI make these instruments valuable beam diagnostic tools for the CEBAF accelerator. This presentation describes the evolution of the Synchrotron Light Interferometer at Jefferson Lab and highlights our extensive experience in the installation and operation of the SLI for CEBAF experimental beam lines.

Report of the Working Group on Far Field Accelerators

International Nuclear Information System (INIS)

Cha-Mei Tang

1992-01-01

This report describes the accomplishments of the Working Group on Far Field Accelerators. In addition to hearing presentations of current research, the group produced designs for ''100 MeV'' demonstration accelerators, ''1 GeV'' conceptual accelerators and a small electron beam source. Two of the ''100 MeV'' designs, an Inverse Free Electron Laser (IFEL) and an Inverse Cerenkov Accelerator (ICA), use the CO 2 laser and the 50 MeV linac at the Advanced Test Facility (ATF) at Brookhaven National Laboratory (BNL), requiring only modest changes in the current experimental setups. By upgrading the laser, an ICA design demonstrated 1 GeV acceleration in a gas cell about 50 cm in length. For high average power accelerators, examples based on the IFEL concept were also produced utilizing accelerators driven by high average power FELs. The Working Group also designed a small electron beam source based on the inverse electron cyclotron resonance concept. Accelerators based on the IFEL and ICA may be the first to achieve ''100 MeV'' and ''1 GeV'' energy gain demonstration with high accelerating gradients

Ion sources for medical accelerators

Science.gov (United States)

Barletta, W. A.; Chu, W. T.; Leung, K. N.

1998-02-01

Advanced injector systems for proton synchrotrons and accelerator-based boron neutron capture therapy systems are being developed at the Lawrence Berkeley National Laboratory. Multicusp ion sources, particularly those driven by radio frequency, have been tested for these applications. The use of a radio frequency induction discharge provides clean, reliable, and long-life source operation. It has been demonstrated that the multicusp ion source can provide good-quality positive hydrogen ion beams with a monatomic ion fraction higher than 90%. The extractable ion current densities from this type of source can meet the injector requirements for both proton synchrotron and accelerator-based boron neutron capture therapy projects.

Technology of magnetically driven accelerators

International Nuclear Information System (INIS)

Brix, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Smith, M.W.

1985-01-01

The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability

Technology of magnetically driven accelerators

International Nuclear Information System (INIS)

Birx, D.L.; Hawkins, S.A.; Poor, S.E.; Reginato, L.L.; Smith, M.W.

1985-01-01

The marriage of Induction Linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 MeV/meter, and with power efficiencies approach 50%. A 2 MeV, 5 kA electron accelerator has been constructed at the Lawrence Livermore National Laboratory (LLNL) to demonstrate these concepts and to provide a test facility for high brightness sources. The pulse drive for the accelerator is based on state-of-the-art magnetic pulse compressors with very high peak power capability, repetition rates exceeding a kilohertz and excellent reliability

Development of circular protons accelerator for ocular teletherapy

International Nuclear Information System (INIS)

Rabelo, L. A.; Campos, T.P.R.

2011-01-01

The proton therapy has been used for ocular tumors providing tumor control in most cases and vision preservations. The protons show high doses in depth depict lower scattering from beam than other particles, electrons and photons. The cyclotron is a type of accelerator that increases the kinetic energy of the charged particle, recirculating it on a magnetic field and crossing an accelerating electrical field. It can be used to produce radioisotopes to hospitals. The goal of this study is to investigate a unit of circular accelerator to be coupled in existing national cyclotrons to generate a proton beams suitable to ocular therapy. Herein, physical parameters are evaluable, including relativistic corrections. That result shows the viability of developing an accelerator unit to ocular proton therapy. (author)

Performance of a DC GaAs photocathode gun for the Jefferson lab FEL

CERN Document Server

Siggins, T; Bohn, C L; Bullard, D; Douglas, D; Grippo, A; Gubeli, J; Krafft, G A; Yunn, B

2001-01-01

The performance of the 320 kV DC photocathode gun has met the design specifications for the 1 kW IR Demo FEL at Jefferson Lab. This gun has shown the ability to deliver high average current beam with outstanding lifetimes. The GaAs photocathode has delivered 135 pC per bunch, at a bunch repetition rate of 37.425 MHz, corresponding to 5 mA average CW current. In a recent cathode lifetime measurement, 20 h of CW beam was delivered with an average current of 3.1 mA and 211 C of total charge from a 0.283 cm sup 2 illuminated spot. The cathode showed a 1/e lifetime of 58 h and a 1/e extracted charge lifetime of 618 C. We have achieved quantum efficiencies of 5% from a GaAs wafer that has been in service for 13 months delivering in excess 2400 C with only three activation cycles.

Development of Micromegas detectors for the CLAS12 experiment at Jefferson Laboratory

CERN Document Server

Charles, Gabriel

This thesis presents my work performed since 2010 to develop Micromegas detectors for the CLAS12 spectrometer that will be installed in the Hall B of Jefferson Laboratory (USA). The Micromegas are robust, fast and cheap gaseous detectors. Nevertheless, they must be adapted to the specific CLAS12 environment as there are many challenges to face : presence of a strong magnetic field, off-detector frontend electronics, high hadrons rate, necessity to curve the detectors, few space available. My PhD started by beam tests at CERN that allowed to evaluate the spark rate in CLAS12 Micromegas at a few Hertz. An important part of this document is therefore devoted to the study of several innovative methods to minimize the dead time induced by sparks. Thus, I have performed intensive tests on the optimization of the micromesh high voltage filter, with on Micromegas equipped with a GEM foild or on resistive Micromegas. The latter giving excellent results, full scale prototypes, one of which built by a company, have been...

A proton medical accelerator by the SBIR route — an example of technology transfer

Science.gov (United States)

Martin, R. L.

1989-04-01

Medical facilities for radiation treatment of cancer with protons have been established in many laboratories throughout the world. Essentially all of these have been designed as physics facilities, however, because of the requirement for protons up to 250 MeV. Most of the experience in this branch of accelerator technology lies in the national laboratories and a few large universities. A major issue is the transfer of this technology to the commercial sector to provide hospitals with simple, reliable and relatively inexpensive accelerators for this application. The author has chosen the SBIR route to accomplish this goal. ACCTEK Associates has received grants from the National Cancer Institute for development of the medical accelerator and beam delivery systems. Considerable encouragement and help has been received from Argonne National Laboratory and the Department of Energy. The experiences to date and the pros and cons on this approach to commercializing medical accelerators are described.

Polarized positrons in Jefferson lab electron ion collider (JLEIC)

Science.gov (United States)

Lin, Fanglei; Grames, Joe; Guo, Jiquan; Morozov, Vasiliy; Zhang, Yuhong

2018-05-01

The Jefferson Lab Electron Ion Collider (JLEIC) is designed to provide collisions of electron and ion beams with high luminosity and high polarization to reach new frontier in exploration of nuclear structure. The luminosity, exceeding 1033 cm-2s-1 in a broad range of the center-of-mass (CM) energy and maximum luminosity above 1034 cm-2s-1, is achieved by high-rate collisions of short small-emittance low-charge bunches with proper cooling of the ion beam and synchrotron radiation damping of the electron beam. The polarization of light ion species (p, d, 3He) and electron can be easily preserved, manipulated and maintained by taking advantage of the unique figure-8 shape rings. With a growing physics interest, polarized positron-ion collisions are considered to be carried out in the JLEIC to offer an additional probe to study the substructure of nucleons and nuclei. However, the creation of polarized positrons with sufficient intensity is particularly challenging. We propose a dedicated scheme to generate polarized positrons. Rather than trying to accumulate "hot" positrons after conversion, we will accumulate "cold" electrons before conversion. Charge accumulation additionally provides a novel means to convert high repetition rate (>100 MHz) electron beam from the gun to a low repetition rate (<100 MHz) positron beam for broad applications. In this paper, we will address the scheme, provide preliminary estimated parameters and explain the key areas to reach the desired goal.

Clinical requirements and accelerator concepts for BNCT

International Nuclear Information System (INIS)

Ludewigt, B.A.; Bleuel, D.L.; Chu, W.T.; Donahue, R.J.; Kwan, J.; Leung, K.N.; Reginato, L.L.; Wells, R.P.

1997-05-01

Accelerator-based neutron sources are an attractive alternative to nuclear reactors for providing epithermal neutron beams for Boron Neutron Capture Therapy. Based on clinical requirements and neutronics modeling the use of proton and deuteron induced reactions in 7 Li and 9 Be targets has been compared. Excellent epithermal neutron beams can be produced via the 7 Li(p,n) 7 Be reaction at proton energies of ∼2.5 MeV. An electrostatic quadrupole accelerator and a lithium target, which can deliver and handle 2.5 MeV protons at beam currents up to 50 mA, are under development for an accelerator-based BNCT facility at the Lawrence Berkeley National Laboratory

Vacuum system of Synchrotron Light National Laboratory (LNLS) linear accelerator: project and results

International Nuclear Information System (INIS)

Rocha, L.R.B.; Gomes, P.A.P.

1990-01-01

The LINAC, electron linear accelerator used as injector for storage ring in production of synchrotron radiation at Laboratorio Nacional de Luz Sincrotron (LNLS) is described. The LINAC basic parameters, the dimension calculations of vacuum system and the final project with all components are presented. The vacuum system for electron gun tests and accelerator structure tests is described. (M.C.K.)

Development of the warm snake and acceleration of polarized protons

International Nuclear Information System (INIS)

Takano, Junpei

2007-01-01

Acceleration of polarized protons is one of interesting issues of the high energy and accelerator physics. As known as the proton spin crisis, the total of the quark spin is not equal to the proton spin. To explore sources of the proton spin, it has been required to accelerate polarized protons to higher energy as hundreds GeV with higher polarization. However it is difficult to accelerate the polarized protons to higher energy with preserving higher polarization by using circular accelerators since the polarized beam crosses several types of depolarizing resonances. To overcome the depolarizing resonances, unique components are employed to the accelerator chain at the Brookhaven National Laboratory (BNL). On this description, developing a normal conducting helical dipole partial Siberian snake is explained in detail. As the results of upgrading the accelerators, the polarization has been increased recently. (author)

Comparisons of American, Israeli, Italian and Mexican physicians and nurses on the total and factor scores of the Jefferson scale of attitudes toward physician-nurse collaborative relationships.

Science.gov (United States)

Hojat, Mohammadreza; Gonnella, Joseph S; Nasca, Thomas J; Fields, Sylvia K; Cicchetti, Americo; Lo Scalzo, Alessandra; Taroni, Francesco; Amicosante, Anna Maria Vincenza; Macinati, Manuela; Tangucci, Massimo; Liva, Carlo; Ricciardi, Gualtiero; Eidelman, Shmuel; Admi, Hanna; Geva, Hana; Mashiach, Tanya; Alroy, Gideon; Alcorta-Gonzalez, Adelina; Ibarra, David; Torres-Ruiz, Antonio

2003-05-01

This cross-cultural study was designed to compare the attitudes of physicians and nurses toward physician-nurse collaboration in the United States, Israel, Italy and Mexico. Total participants were 2522 physicians and nurses who completed the Jefferson Scale of Attitudes Toward Physician-Nurse Collaboration (15 Likert-type items, (Hojat et al., Evaluation and the Health Professions 22 (1999a) 208; Nursing Research 50 (2001) 123). They were compared on the total scores and four factors of the Jefferson Scale (shared education and team work, caring as opposed to curing, nurses, autonomy, physicians' dominance). Results showed inter- and intra-cultural similarities and differences among the study groups providing support for the social role theory (Hardy and Conway, Role Theory: Perspectives for Health Professionals, Appelton-Century-Crofts, New York, 1978) and the principle of least interest (Waller and Hill, The Family: A Dynamic Interpretation, Dryden, New York, 1951) in inter-professional relationships. Implications for promoting physician-nurse education and inter-professional collaboration are discussed.

Heavy ion accelerator GANIL

International Nuclear Information System (INIS)

1975-04-01

This article presents GANIL, a large national heavy ion accelerator. The broad problems of nuclear physics, atomic physics, astrophysics and physics of condensed media which can be approached and studied with this machine are discussed first, after which the final construction project is described. The project comprises a circular injector, a separated sector cyclotron up beam stripper, and a second separated cyclotron downstream [fr

State registration and inspection programs for particle accelerators

International Nuclear Information System (INIS)

Bailey, E.D.

1976-01-01

The Suggested State Regulations for Control of Radiation(SSRCR) are recommended by the Council of State Governments and the National Conference of Radiation Control Program Directors as the model regulations which states should adopt in order to have adequate regulation and uniformity from state to state. These regulations are used as a basis for reviewing the current status of accelerator regulation in each state. The SSRCR does contain a separate part for registration (Part B--Registration of Radiation Machine Facilities and Services) and a separate part (Part I--Radiation Safety Requirements for Particle Accelerators) with specific requirements for the possession and use of accelerators. In addition, medical accelerators have additional requirements in Part F--X-Rays in The Heating Acts. These regulations specify requirements related to limitations of use, shielding and safety design requirements, control and interlock systems, warning devices, operating procedures, radiation monitoring, and calibration of medical accelerators

Technical meeting (TM) to 'Review of national programmes on fast reactors and accelerator driven systems (ADS)'. Technical Working Group on Fast Reactors (TWG-FR) (37th annual meeting). Working material

Energy Technology Data Exchange (ETDEWEB)

NONE

2004-07-01

The objectives of the 37th Annual Meeting of the Technical Working Group on Fast Reactors, were to: 1) exchange information on the national programmes on Fast Reactors (FR) and Accelerator Driven Systems (ADS); 2) review the progress since the 36th TWG-FR Annual Meeting, including the status of the actions; 3) consider meeting arrangements for 2004 and 2005; 4) review the Agency's co-ordinated research activities in the field of FRs and ADS, as well as co-ordination of the TWG-FR's activities with other organizations. The participants made presentations on the status of the respective national programmes on FR and ADS development. A summary of the highlights for the period since the 36th TWG-FR Annual Meeting is included in this proceedings. Annex IV contains the Review of National Programs on Fast Reactors and Accelerator Driven Systems (ADS), and the TWG-FR Activity Report for the Period May 2003-April 2004.

Marie Curie: the Curie Institute in Senegal to Nuclear Physics

Science.gov (United States)

Gueye, Paul

Sub-Saharan Africa is not a place where one will look first when radioactivity or nuclear physics is mentioned. Conducting forefront research at the international stage at US national facilities such as the Thomas Jefferson National Accelerator Facility in Virginia or the National Superconducting Cyclotron Facility/Facility for Rare Isotope Beams in Michigan does not point to Historically Black Colleges either. The two are actually intrinsically connected as my personal journey from my early exposure to radiation at the Curie Institute at the LeDantec Hospital in Senegal lead me to Hampton University. The former, through one of my uncles, catapulted me into a nuclear physics PhD while the latter houses the only nuclear physics program at an HBCU to date that has established itself as one of the premier programs in the nation. This talk will review the impact of Marie Curie in my life as a nuclear physicist.

Computing Properties of Hadrons, Nuclei and Nuclear Matter from Quantum Chromodynamics (LQCD)

Energy Technology Data Exchange (ETDEWEB)

Negele, John [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

2017-08-31

Building on the success of two preceding generations of Scientific Discovery through Advanced Computing (SciDAC) projects, this grant supported the MIT component (P.I. John Negele) of a multi-institutional SciDAC-3 project that also included Brookhaven National Laboratory, the lead laboratory with P. I. Frithjof Karsch serving as Project Director, Thomas Jefferson National Accelerator Facility with P. I. David Richards serving as Co-director, University of Washington with P. I. Martin Savage, University of North Carolina with P. I. Rob Fowler, and College of William and Mary with P. I. Andreas Stathopoulos. Nationally, this multi-institutional project coordinated the software development effort that the nuclear physics lattice QCD community needs to ensure that lattice calculations can make optimal use of forthcoming leadership-class and dedicated hardware, including that at the national laboratories, and to exploit future computational resources in the Exascale era.

Charged particle accelerators for inertial fusion energy

International Nuclear Information System (INIS)

Humphries, S. Jr.

1991-01-01

The long history of successful commercial applications of charged-particle accelerators is largely a result of initiative by private industry. The Department of Energy views accelerators mainly as support equipment for particle physicists rather than components of an energy generation program. In FY 91, the DOE spent over 850 M$ on building and supporting accelerators for physics research versus 5 M$ on induction accelerators for fusion energy. The author believes this emphasis is skewed. One must address problems of long-term energy sources to preserve the possibility of basic research by future generations. In this paper, the author reviews the rationale for accelerators as inertial fusion drivers, emphasizing that these devices provide a viable path of fusion energy from viewpoints of both physics and engineering. In this paper, he covered the full range of accelerator fusion applications. Because of space limitations, this paper concentrates on induction linacs for ICF, an approach singled out in recent reports by the National Academy of Sciences and the Fusion Policy Advisory Committee as a promising path to long-term fusion power production. Review papers by Cook, Leung, Franzke, Hofmann and Reiser in these proceedings give details on light ion fusion and RF accelerator studies

A single-beam deuteron compact accelerator for neutron generation

International Nuclear Information System (INIS)

Araujo, Wagner Leite; Campos, Tarcisio Passos Ribeiro de

2011-01-01

Portable neutron generators are devices composed by small size accelerators that produce neutrons through fusion between hydrogen isotopes. These reactions are characterized by appreciable cross section at energies at the tens of keV, which enables device portability. The project baselines follow the same physical and engineering principles of any other particle accelerators. The generator consists of a gas reservoir, apparatus for ion production, few electrodes to accelerate and focus the ion beam, and a metal hydride target where fusion reactions occur. Neutron generator applications include geophysical measurements, indus- trial process control, environmental, research, nation's security and mechanical structure analysis.This article presents a design of a compact accelerator for d-d neutron generators, describing the physical theory applied to the deuteron extraction system, and simulating the ion beam transport in the accelerator. (author)

New developments in particle acceleration techniques. Proceedings. Vol. 2

International Nuclear Information System (INIS)

Turner, S.

1987-01-01

A Workshop organised jointly by the European Committee for Future Accelerators (ECFA), the CERN Accelerator School (CAS), the Institut National de Physique Nucleaire et de Physique des Particules (IN2P3), the Institut pour la Recherche Fondamentale/Commissariat a l'Energie Atomique (IRF/CEA) and the European Physical Society (EPS) was held at the Laboratoire de l'Accelerateur Lineaire (LAL), Orsay, from 29 June to 4 July 1987. Its purpose was to review current experimental and theoretical developments in charged-particle accelerator techniques and to address problems related to future very-high-energy machines. These proceedings contain the great majority of the papers presented at the Workshop, the corresponding questions and answers, and the round-table discussion. The principal topics were semi-conventional high-frequency linacs, transformer acceleration mechanisms, acceleration using plasma, e + e - sources, including low-emittance production and preservation, final focus and interaction point, and other new ideas. Among the latter were open accelerating structures, crystal X-ray accelerators, ferroelectrics, and acceleration using lasers. (orig.)

New developments in particle acceleration techniques. Proceedings. Vol. 1

International Nuclear Information System (INIS)

Turner, S.

1987-01-01

A Workshop organised jointly by the European Committee for Future Accelerators (ECFA), the CERN Accelerator School (CAS), the Institut National de Physique Nucleaire et de Physique des Particules (IN2P3), the Institut pour la Recherche Fondamentale/Commissariat a l'Energie Atomique (IRF/CEA) and the European Physical Society (EPS) was held at the Laboratoire de l'Accelerateur Lineaire (LAL), Orsay, from 29 June to 4 July 1987. Its purpose was to review current experimental and theoretical developments in charged-particle accelerator techniques and to address problems related to future very-high-energy machines. These proceedings contain the great majority of the papers presented at the Workshop, the corresponding questions and answers, and the round-table discussion. The principal topics were semi-conventional high-frequency linacs, transformer acceleration mechanisms, acceleration using plasma, e + e - sources including low-emittance production and preservation, final focus and interaction point, and other new ideas. Among the latter were open accelerating structures, crystal X-ray accelerators, ferroelectrics, and acceleration using lasers. (orig.)

ORNL 25 MV tandem accelerator control system

International Nuclear Information System (INIS)

Juras, R.C.; Biggerstaff, J.A.; Hoglund, D.E.

1985-01-01

The CAMAC-based control system for the 25 MV tandem electrostatic accelerator of the Holifield Heavy Ion Research Facility at Oak Ridge National Laboratory (ORNL) was specified by ORNL and built by the National Electrostatics Corporation. Two Perkin-Elmer 32-bit minicomputers are used in the system, a message switching computer and a supervisory computer. The message switching computer transmits and receives control information on six serial highways. This computer shares memory with the supervisory computer. Operator consoles are located on a serial highway; control is by means of a console CRT, trackball, and assignable shaft encoders and meters. Two identical consoles operate simultaneously: one is located in the tandem control room; the other is located in the cyclotron control room to facilitate operation during injection of tandem beams into the cyclotron or when beam lines under control of the cyclotron control system are used. The supervisory computer is used for accelerator parameter setup calculations, actual accelerator setup for new beams based on scaled, recorded parameters from previously run beams, and various other functions. Nearly seven years of control system operation and improvements will be discussed

Polarized ionic source of the tandem accelerator in Kyoto University

Energy Technology Data Exchange (ETDEWEB)

Nakamura, Masanobu; Kuwamoto, Shuichi; Takahashi, Seiji [Kyoto Univ. (Japan). Dept. of Physics] [and others

1997-02-01

A polarized ion source developed under the National Laboratory of High Energy Physics was transferred to the tandem accelerator in Kyoto University at beginning of 1993 to constitute a displacement of incidence into the accelerator. This was an atomic beam type polarized ion source, which is designed to adopt permanent magnets for 6 poles magnet to polarize the electron, to take out atomic nucleus on a shape of positive ion by ECR ionizer after transferring its polarization through transition using radio frequency (RFT), to make it negative ion by charge conversion using alkaline metal vapor, and to put it into the tandem accelerator. Test of the positive ion was finished at the National Laboratory of High Energy Physics, and test in Kyoto University was required after its negative ionization. As the estimated cost was unsufficient and entrance into the ion source facility in the tandem accelerator building was limited in Kyoto University, step of development was slow. Here is reported on present state of the ion source which is now operating stably. (G.K.)

Heavy ion medical accelerator in chiba

International Nuclear Information System (INIS)

Hirao, Y.; Ogawa, H.; Yamada, S.

1992-12-01

The HIMAC (Heavy Ion Medical Accelerator in Chiba) construction project has been promoted by NIRS (National Institute of Radiological Sciences) as one of the projects of 'Comprehensive 10 year Strategy for Cancer Control' HIMAC is the first heavy-ion accelerator dedicated to medicine in the world, and its design parameters are based on the radiological requirements. It consists of two types of ion sources, an RFQ and an Alvarez linacs, dual synchrotron rings, high energy beam transport lines, and irradiation facilities for treatment and experiments. This report mainly describes the outline of the structure and performance of each HIMAC subsystem. (J.P.N.)

Developments of electron accelerators for national economy in the AN SSSR SO IYaF

International Nuclear Information System (INIS)

Auslender, V.L.; Salimov, R.A.

1979-01-01

Described is the work aimed at developing ELV-type electrostatic electron accelerators with electron energies ranging from 0.4 to 1.5 MeV and an average beam current of up to 100 mA, and the ILU-6 electron linear accelerator with the energy from 0.5 to 2 MeV and an average beam current of up to 40 mA. To provide an output of a linearly scanned beam a special titanium window with dimension of 75 x 980 mm which provides transit of a current of up to 80 mA has been developed. To irradiate articles having a cylindrical shape two types of devices with a circular beam scanning have been developed. A device has been worked out for the output of concentrated beams into the atmosphere, in which the electron beam leaves the vacuum through a system of four ports having different diameters. Principles of operation and results of tests of these devices are briefly outlined. Examples of their application are given. More than ten tons of tubes have been irradiated on the ILU-6 accelerator to obtain thermal shrinkage, and this accelerator also served as the basis for developing a radiation sewage treatment plant. An annual economical effect is estimated at 2 million roubles per an accelerator

Turn-key SRF accelerators to drive subcritical reactors

International Nuclear Information System (INIS)

Johnson, Rolland P.

2011-01-01

Large particle accelerator projects, both accomplished and proposed, have been used to engage US industry through contracts and grants to develop efficient capabilities to design, develop, produce, and deliver entire accelerator systems or any needed subsystems. Staffed in many cases by experienced scientists and engineers from National Laboratories and Universities, existing companies could extend their portfolios to offer turn-key accelerators with parameters to match the needs of ADS. If the reactors were based on molten salt fuel such that trip rate requirements were relaxed, the developments needed for a multi-MW proton accelerator for ADS would be minimal. Turn-key SRF proton linacs for ADS operation can be ordered now to enable GW-level power generation from natural thorium, natural uranium, or nuclear waste from conventional reactors. (author)

Developing a clinical proton accelerator facility: Consortium-assisted technology transfer

International Nuclear Information System (INIS)

Slater, J.M.; Miller, D.W.; Slater, J.W.

1991-01-01

A hospital-based proton accelerator facility has emerged from the efforts of a consortium of physicists, engineers and physicians from several high-energy physics laboratories, industries and universities, working together to develop the requirements and conceptual design for a clinical program. A variable-energy medical synchrotron for accelerating protons to a prescribed energy, intensity and beam quality, has been placed in a hospital setting at Loma Linda University Medical Center for treating patients with localized cancer. Treatments began in October 1990. Scientists from Fermi National Accelerator Laboratory; Harvard Cyclotron Laboratory; Lawrence Berkeley Laboratories; the Paul Scherrer Institute; Uppsala, Sweden; Argonne, Brookhaven and Los Alamos National Laboratories; and Loma Linda University, all cooperated to produce the conceptual design. Loma Linda University contracted with Fermi National Accelerator Laboratory to design and build a 250 MeV synchrotron and beam transport system, the latter to guide protons into four treatment rooms. Lawrence Berkeley Laboratories consulted with Loma Linda University on the design of the beam delivery system (nozzle). A gantry concept devised by scientists at Harvard Cyclotron Laboratory, was adapted and fabricated by Science Applications International Corporation. The control and safety systems were designed and developed by Loma Linda University Radiation Research Laboratory. Presently, the synchrotron, beam transport system and treatment room hardware have been installed and tested and are operating satisfactorily

Improved 36Cl performance at the ASTER HVE 5 MV accelerator mass spectrometer national facility

International Nuclear Information System (INIS)

Finkel, R.; Arnold, M.; Aumaître, G.; Benedetti, L.; Bourlès, D.; Keddadouche, K.; Merchel, S.

2013-01-01

The HVE 5 MV ASTER AMS national facility at CEREGE was accepted in 2007. Since then we have continued to optimize performance for 36 Cl. Cl-36 analyses use AgCl, a Cs negative ion sputter source, Ar stripping to +5 in the terminal of the Tandetron™ accelerator at 5 MV and a silicon nitride post-acceleration stripper foil to enhance suppression of 36 S relative to 36 Cl. The major challenges to obtaining the desired performance for Earth science applications are ion source memory, mass fractionation effects, 36 S isobar suppression and sensitivity. Redesign of the SO110 ion source by HVE to change the size of the aperture and the shape of cathode significantly reduced ion source memory to less than ∼0.1%, a level that can be compensated for by matching standards to samples. We observe small systematic drifts in 35 Cl/ 37 Cl ratios over time, the source of which is not yet determined. Measurement of standards indicates that this effect limits the precision of 35 Cl/ 37 Cl ratio determination to about 2%. 36 S is suppressed in several ways. First, the sample chemistry has been designed to reduce S to low levels. Second, cathodes are constructed of low-S nickel, enabling direct target loading without the use of AgBr pre-packing. Third, a post-acceleration Si 3 N 4 stripper foil differentially absorbs energy from 36 Cl and 36 S. A subsequent electrostatic deflector is then able to suppress 36 S by a factor of ∼240 relative to 36 Cl. Differential energy loss in the detector further suppresses 36 S by about 10 −4 , for an overall suppression factor of 4 × 10 −7 . 36 S count rates are typically equivalent to a background 36 Cl/Cl of ∼10 −15 . At typical 35 Cl currents of ∼20 μA Cl 5+ samples with 36 Cl/ 35 Cl of 6 × 10 −14 can be measured to ±5% statistical uncertainty with 1 h of analysis time. Typical machine blanks have 36 Cl/Cl ∼2 × 10 −15 .

Rayleigh-Taylor mixing with time-dependent acceleration

Science.gov (United States)

Abarzhi, Snezhana

2016-10-01

We extend the momentum model to describe Rayleigh-Taylor (RT) mixing driven by a time-dependent acceleration. The acceleration is a power-law function of time, similarly to astrophysical and plasma fusion applications. In RT flow the dynamics of a fluid parcel is driven by a balance per unit mass of the rates of momentum gain and loss. We find analytical solutions in the cases of balanced and imbalanced gains and losses, and identify their dependence on the acceleration exponent. The existence is shown of two typical regimes of self-similar RT mixing-acceleration-driven Rayleigh-Taylor-type and dissipation-driven Richtymer-Meshkov-type with the latter being in general non-universal. Possible scenarios are proposed for transitions from the balanced dynamics to the imbalanced self-similar dynamics. Scaling and correlations properties of RT mixing are studied on the basis of dimensional analysis. Departures are outlined of RT dynamics with time-dependent acceleration from canonical cases of homogeneous turbulence as well as blast waves with first and second kind self-similarity. The work is supported by the US National Science Foundation.

Menopause accelerates biological aging

Science.gov (United States)

Levine, Morgan E.; Lu, Ake T.; Chen, Brian H.; Hernandez, Dena G.; Singleton, Andrew B.; Ferrucci, Luigi; Bandinelli, Stefania; Salfati, Elias; Manson, JoAnn E.; Quach, Austin; Kusters, Cynthia D. J.; Kuh, Diana; Wong, Andrew; Teschendorff, Andrew E.; Widschwendter, Martin; Ritz, Beate R.; Absher, Devin; Assimes, Themistocles L.; Horvath, Steve

2016-01-01

Although epigenetic processes have been linked to aging and disease in other systems, it is not yet known whether they relate to reproductive aging. Recently, we developed a highly accurate epigenetic biomarker of age (known as the “epigenetic clock”), which is based on DNA methylation levels. Here we carry out an epigenetic clock analysis of blood, saliva, and buccal epithelium using data from four large studies: the Women's Health Initiative (n = 1,864); Invecchiare nel Chianti (n = 200); Parkinson's disease, Environment, and Genes (n = 256); and the United Kingdom Medical Research Council National Survey of Health and Development (n = 790). We find that increased epigenetic age acceleration in blood is significantly associated with earlier menopause (P = 0.00091), bilateral oophorectomy (P = 0.0018), and a longer time since menopause (P = 0.017). Conversely, epigenetic age acceleration in buccal epithelium and saliva do not relate to age at menopause; however, a higher epigenetic age in saliva is exhibited in women who undergo bilateral oophorectomy (P = 0.0079), while a lower epigenetic age in buccal epithelium was found for women who underwent menopausal hormone therapy (P = 0.00078). Using genetic data, we find evidence of coheritability between age at menopause and epigenetic age acceleration in blood. Using Mendelian randomization analysis, we find that two SNPs that are highly associated with age at menopause exhibit a significant association with epigenetic age acceleration. Overall, our Mendelian randomization approach and other lines of evidence suggest that menopause accelerates epigenetic aging of blood, but mechanistic studies will be needed to dissect cause-and-effect relationships further. PMID:27457926

Investigating the psychometric properties of the Jefferson Scale of Physician Empathy in a sample of Malaysian medical students

Directory of Open Access Journals (Sweden)

Spasenoska M

2016-06-01

Full Text Available Marija Spasenoska,1 Shane Costello,1 Brett Williams2 1Faculty of Education, 2Department of Community Emergency Health and Paramedic Practice, Monash University, Melbourne, VIC, Australia Objective: The purpose of this present study was to investigate the psychometric properties of the Jefferson Scale of Physician Empathy – student version (JSPE-S. Subjects and methods: This study recruited 193 Malaysian medical students enrolled in year one and year two studies. A principal-component analysis with Varimax rotation was conducted. Procrustes rotation was used to confirm the item to model fit, which allows for a comparison of actual structure against an ideal hypothesized structure. Items were systematically removed based on low communalities of < 0.3 and poor loading of items onto components. Results: A two-component solution was found, comprised of “perspective taking” and “compassionate care”. Following item removal, eleven items remained. A Procrustes analysis revealed that this eleven-item measure demonstrated an excellent model fit. A possible third component was identified, though is not recommended for use, due to construct underrepresentation. Conclusion: This study found the Jefferson Scale of Physician Empathy fitted best to a two-component model using eleven items. Item, component, and overall congruence were very high, and scale reliabilities were adequate. The results of this study suggest that the eleven-item, two-component solution demonstrates excellent psychometric properties and structural validity in a Malaysian medical student population. Future research could consider using the short eleven-item measure in both student and health care profession samples to investigate the role of empathy in health care. Keywords: empathy, medical students, psychometrics

The BNL Accelerator Test Facility and experimental program

International Nuclear Information System (INIS)

Ben-Zvi, I.; State Univ. of New York, Stony Brook, NY

1992-01-01

The Accelerator Test Facility (ATF) at BNL is a users' facility for experiments in Accelerator and Beam Physics. The ATF provides high brightness electron beams and high-power laser pulses synchronized to the electron beam, suitable for studies of new methods of high-gradient acceleration and state-of-the-art Free-Electron Lasers. The electrons are produced by a laser photocathode rf gun and accelerated to 50 MeV by two traveling wave accelerator sections. The lasers include a 10 mJ, 10 ps ND:YAG laser and a 500 mJ, 10 to 100 ps C0 2 laser. A number of users from National Laboratories, universities and industry take part in experiments at the ATF. The experimental program includes various laser acceleration schemes, Free-Electron Laser experiments and a program on the development of high-brightness electron beams. The ATF's experimental program commenced in early 1991 at an energy of about 4 MeV. The full program, with 50 MeV and the high-power laser will begin operation this year

The BNL Accelerator Test Facility and experimental program

International Nuclear Information System (INIS)

Ben-Zvi, I.; State Univ. of New York, Stony Brook, NY

1991-01-01

The Accelerator Test Facility (ATF) at BNL is a users' facility for experiments in Accelerator and Beam Physics. The ATF provides high brightness electron beams and high power laser pulses synchronized to the electron beam, suitable for studies of new methods of high gradient acceleration and state of the art free electron lasers. The electrons are produced by a laser photocathode rf gun and accelerated to 50 to 100 MeV by two traveling wave accelerator sections. The lasers include a 10 mJ, 10 ps Nd:YAG laser and a 100 mJ, 10 ps CO 2 laser. A number of users from National Laboratories, universities and industry take part in experiments at the ATF. The experimental program includes various acceleration schemes, Free-Electron Laser experiments and a program on the development of high brightness electron beams. The AFT's experimental program commenced in early 1991 at an energy of about 4 MeV. The full program, with 50 MeV and the High power laser will begin operation this year. 28 refs., 4 figs

The BNL Accelerator Test Facility control system

International Nuclear Information System (INIS)

Malone, R.; Bottke, I.; Fernow, R.; Ben-Zvi, I.

1993-01-01

Described is the VAX/CAMAC-based control system for Brookhaven National Laboratory's Accelerator Test Facility, a laser/linac research complex. Details of hardware and software configurations are presented along with experiences of using Vsystem, a commercial control system package

Dorothy Davison (1890-1984): Manchester medical artist and her work for neurosurgeon Sir Geoffrey Jefferson (1886-1961).

Science.gov (United States)

Mohr, Peter D

2017-05-01

Miss Davison was a medical artist at the Manchester Royal Infirmary and the University of Manchester from around 1918 until her retirement in 1957. She illustrated books and scientific papers on anthropology, anatomy and surgery, and became well known for her striking pictures produced by the 'Ross board technique'- a difficult process that she helped pioneer from the 1930s and which forms the bulk of the work she undertook for neurosurgeon Geoffrey Jefferson during the 1930s-1950s. His Neurosurgical Department became the main base for her work until his retirement in 1953. She was an active member of the Medical Artist Association (MAA) which she helped found in 1949.

Neutron Transport Methods for Accelerator-Driven Systems

International Nuclear Information System (INIS)

Nicholas Tsoulfanidis; Elmer Lewis

2005-01-01

The objective of this project has been to develop computational methods that will enable more effective analysis of Accelerator Driven Systems (ADS). The work is centered at the University of Missouri at Rolla, with a subcontract at Northwestern University, and close cooperation with the Nuclear Engineering Division at Argonne National Laboratory. The work has fallen into three categories. First, the treatment of the source for neutrons originating from the spallation target which drives the neutronics calculations of the ADS. Second, the generalization of the nodal variational method to treat the R-Z geometry configurations frequently needed for scoping calculations in Accelerator Driven Systems. Third, the treatment of void regions within variational nodal methods as needed to treat the accelerator beam tube

Baseline review of the U.S. LHC Accelerator project

International Nuclear Information System (INIS)

1998-02-01

The Department of Energy (DOE) Review of the U.S. Large Hadron Collider (LHC) Accelerator project was conducted February 23--26, 1998, at the request of Dr. John R. O'Fallon, Director, Division of High Energy Physics, Office of Energy Research, U.S. DOE. This is the first review of the U.S. LHC Accelerator project. Overall, the Committee found that the U.S. LHC Accelerator project effort is off to a good start and that the proposed scope is very conservative for the funding available. The Committee recommends that the project be initially baselined at a total cost of $110 million, with a scheduled completion data of 2005. The U.S. LHC Accelerator project will supply high technology superconducting magnets for the interaction regions (IRs) and the radio frequency (rf) straight section of the LHC intersecting storage rings. In addition, the project provides the cryogenic support interface boxes to service the magnets and radiation absorbers to protect the IR dipoles and the inner triplet quadrupoles. US scientists will provide support in analyzing some of the detailed aspects of accelerator physics in the two rings. The three laboratories participating in this project are Brookhaven National Laboratory, Fermi National Accelerator Laboratory (Fermilab), and Lawrence Berkeley National Laboratory. The Committee was very impressed by the technical capabilities of the US LHC Accelerator project team. Cost estimates for each subsystem of the US LHC Accelerator project were presented to the Review Committee, with a total cost including contingency of $110 million (then year dollars). The cost estimates were deemed to be conservative. A re-examination of the funding profile, costs, and schedules on a centralized project basis should lead to an increased list of deliverables. The Committee concluded that the proposed scope of US deliverables to CERN can be readily accomplished with the $110 million total cost baseline for the project. The current deliverables should serve as

Accelerated Aging Experiments for Capacitor Health Monitoring and Prognostics

Data.gov (United States)

National Aeronautics and Space Administration — This paper discusses experimental setups for health monitoring and prognostics of electrolytic capacitors under nominal operation and accelerated aging conditions....

Acceleration of laser-injected electron beams in an electron-beam driven plasma wakefield accelerator

International Nuclear Information System (INIS)

Knetsch, Alexander

2018-03-01

Plasma wakefields deliver accelerating fields that are approximately a 100 times higher than those in conventional radiofrequency or even superconducting radiofrequency cavities. This opens a transformative path towards novel, compact and potentially ubiquitous accelerators. These prospects, and the increasing demand for electron accelerator beamtime for various applications in natural, material and life sciences, motivate the research and development on novel plasma-based accelerator concepts. However, these electron beam sources need to be understood and controlled. The focus of this thesis is on electron beam-driven plasma wakefield acceleration (PWFA) and the controlled injection and acceleration of secondary electron bunches in the accelerating wake fields by means of a short-pulse near-infrared laser. Two laser-triggered injection methods are explored. The first one is the Trojan Horse Injection, which relies on very good alignment and timing control between electron beam and laser pulse and then promises electron bunches with hitherto unprecedented quality as regards emittance and brightness. The physics of electron injection in the Trojan Horse case is explored with a focus on the final longitudinal bunch length. Then a theoretical and numerical study is presented that examines the physics of Trojan Horse injection when performed in an expanding wake generated by a smooth density down-ramp. The benefits are radically decreased drive-electron bunch requirements and a unique bunch-length control that enables longitudinal electron-bunch shaping. The second laser-triggered injection method is the Plasma Torch Injection, which is a versatile, all-optical laser-plasma-based method capable to realize tunable density downramp injection. At the SLAC National Laboratory, the first proof-of-principle was achieved both for Trojan Horse and Plasma Torch injection. Setup details and results are reported in the experimental part of the thesis along with the commissioning

X Latin American Symposium on Nuclear Physics and Applications. Book of Abstracts

International Nuclear Information System (INIS)

2013-12-01

The 10th Latin American Symposium on Nuclear Physics and Applications will be held on December 1-6, 2013 in Montevideo, Uruguay. The symposium will be preceded by a School on Medical Physics, on November 29-30, 2013. The symposium is organized by the Universidad de la Repùblica, Montevideo, by the National Superconducting Cyclotron Laboratory, Michigan, USA, and by the Thomas Jefferson National Accelerator Facility, Virginia, USA. This is the tenth event in a series which were previously held in Venezuela, Colombia, Mexico, Brazil, Argentina, Peru, Chile and Ecuador. Traditionally, the purpose of these symposia is the dissemination of major theoretical and experimental advances in nuclear science, with emphasis on research topics carried out by Latin American groups or in collaborations involving institutions from Latin America. The topics of the symposium include: Nuclear and Hadron Structure and Interactions Nuclear Reactions and Phases of Nuclear Matter Nuclear and Particle Astrophysics Tests of Fundamental Symmetries and Properties of Neutrinos Nuclear Applications New Facilities and Instrumentation.The 10th Latin American Symposium on Nuclear Physics and Applications will be held on December 1-6, 2013 in Montevideo, Uruguay. The symposium will be preceded by a School on Medical Physics, on November 29-30, 2013. The symposium is organized by the Universidad de la República, Montevideo, by the National Superconducting Cyclotron Laboratory, Michigan, USA, and by the Thomas Jefferson National Accelerator Facility, Virginia, USA. This is the tenth event in a series which were previously held in Venezuela, Colombia, Mexico, Brazil, Argentina, Peru, Chile and Ecuador. Traditionally, the purpose of these symposia is the dissemination of major theoretical and experimental advances in nuclear science, with emphasis on research topics carried out by Latin American groups or in collaborations involving institutions from Latin America. The topics of the symposium include

STEVENSON-WYDLER (15 USC 3710) COOPERATIVE RESEARCH AND DEVELOPMENT AGREEMENT No. JSA 2009S007 BETWEEN Jefferson ScienceAssociates, LLC under its U.S.Department of Energy Contract No. DE-AC05-060R23 177 AND Black Laboratories, L.L.C.

Energy Technology Data Exchange (ETDEWEB)

Crooks, Roy [Black Lab., LLC, Newport News, VA (United States)

2018-02-08

The Cooperative Research and Development agreement, No. JSA 2009S00 resulted in collaborations and conference participations on research topics related to high purity (RRR) niobium applications for superconducting radio frequency cavities used by Jefferson Lab. Documented results were shown in Reports and Publications listed below. Reports were issued to The Commonwealth of Virginia, Center for Innovative Technology; to ATI Wah-Chang and several publications were produced with DESY in Hamburg, Germany, with Jefferson Lab and with Christopher Newport University.

The g0 parity violation experiment:overview and status after the first commissioning run

International Nuclear Information System (INIS)

Bimbot, L.

2004-01-01

The basis of the G 0 experiment is a parity-violating process giving access to the strange form factors of the proton. It requires the measurement of a set of asymmetries, in elastic electron scattering from hydrogen and quasi-elastic scattering from deuterium, at different Q 2 and at different angles. The experimental site is the Thomas Jefferson National Accelerator Facility (J Lab.), Newport News, VA (USA). The formalism that connects asymmetries with the proton properties at the quark level, the experimental set-up and the present status are described. A section is devoted to a special electronic module, built at the IPN-Orsay, using Digital Signal Processors (DSPs)

Differential cross sections and polarization observables from CLAS K⁎ photoproduction and the search for new N⁎ states

Directory of Open Access Journals (Sweden)

A.V. Anisovich

2017-08-01

Full Text Available The reaction γp→K⁎+Λ was measured using the CLAS detector for photon energies between the threshold and 3.9 GeV at the Thomas Jefferson National Accelerator Facility. For the first time, spin-density matrix elements have been extracted for this reaction. Differential cross sections, spin density matrix elements, and the Λ recoil polarization are compared with theoretical predictions using the BnGa partial wave analysis. The main result is the evidence for significant contributions from N(18951/2− and N(21001/2+ to the reaction. Branching ratios for decays into K⁎Λ for these resonances and further resonances are reported.

Baryon spectroscopy with polarization observables from CLAS

Energy Technology Data Exchange (ETDEWEB)

Strauch, Steffen [Univ. of South Carolina, Columbia, SC (United States); Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

2016-11-01

The spectrum of nucleon excitations is dominated by broad and overlapping resonances. Polarization observables in photoproduction reactions are key in the study of these excitations. They give indispensable constraints to partial-wave analyses and help clarify the spectrum. A series of polarized photoproduction experiments have been performed at the Thomas Jefferson National Accelerator Facility with the CEBAF Large Acceptance Spectrometer (CLAS). These measurements include data with linearly and circularly polarized tagged-photon beams, longitudinally and transversely polarized proton and deuterium targets, and recoil polarizations through the observation of the weak decay of hyperons. An overview of these studies and recent results will be given.

Differential cross sections and polarization observables from CLAS K* photoproduction and the search for new N* states

Science.gov (United States)

Anisovich, A. V.; Hicks, K.; Klempt, E.; Nikonov, V. A.; Sarantsev, A.; Tang, W.; Adikaram, D.; Akbar, Z.; Amaryan, M. J.; Anefalos Pereira, S.; Badui, R. A.; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Briscoe, W. J.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Chetry, T.; Ciullo, G.; Clark, L.; Cole, P. L.; Compton, N.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dugger, M.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Filippi, A.; Fleming, J. A.; Gevorgyan, N.; Ghandilyan, Y.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Gothe, R. W.; Griffioen, K. A.; Guo, L.; Hanretty, C.; Harrison, N.; Hattawy, M.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joosten, S.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, W.; Klein, F. J.; Kubarovsky, V.; Lanza, L.; Lenisa, P.; Livingston, K.; MacGregor, I. J. D.; Markov, N.; McKinnon, B.; Meyer, C. A.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Murdoch, G.; Nadel-Turonski, P.; Net, L. A.; Ni, A.; Niccolai, S.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Ritchie, B. G.; Rosner, G.; Roy, P.; Sabatié, F.; Schumacher, R. A.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stankovic, I.; Stepanyan, S.; Strauch, S.; Sytnik, V.; Tian, Ye.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wood, M. H.; Zachariou, N.; Zhang, J.; Zonta, I.; CLAS Collaboration

2017-08-01

The reaction γp →K*+ Λ was measured using the CLAS detector for photon energies between the threshold and 3.9 GeV at the Thomas Jefferson National Accelerator Facility. For the first time, spin-density matrix elements have been extracted for this reaction. Differential cross sections, spin density matrix elements, and the Λ recoil polarization are compared with theoretical predictions using the BnGa partial wave analysis. The main result is the evidence for significant contributions from N (1895) 1 /2- and N (2100) 1 /2+ to the reaction. Branching ratios for decays into K* Λ for these resonances and further resonances are reported.

Advanced Accelerator Applications University Participation Program

International Nuclear Information System (INIS)

Chen, Y.; Hechanova, A.

2007-01-01

Our research tasks span the range of technology areas for transmutation, gas-cooled reactor technology, and high temperature heat exchangers, including separation of actinides from spent nuclear fuel, methods of fuel fabrication, reactor-accelerator coupled experiments, corrosion of materials exposed to lead-bismuth eutectic, and special nuclear materials protection and accountability. In the six years of this program, we saw the evolution of the national transmutation concepts go from the use of accelerators to fast reactors. We also saw an emphasis on gas-cooled reactors for both high temperature heat and deep burn of nuclear fuel. At the local level, we saw a great birth at UNLV of two new academic programs Fall term of 2004 and the addition of 10 academic and research faculty. The Ph.D. program in Radiochemistry has turned into one of the nation's most visible and successful programs; and, the M.S. program in Materials and Nuclear Engineering initiated Nuclear Engineering academic opportunities which took a long time to come. Our research tasks span the range of technology areas for transmutation, gas-cooled reactor technology, and high temperature heat exchangers, including separation of actinides from spent nuclear fuel, methods of fuel fabrication, reactor-accelerator coupled experiments, corrosion of materials exposed to lead-bismuth eutectic, and special nuclear materials protection and accountability

Materials Science Division HVEM-Tandem Facility at Argonne National Laboratory

International Nuclear Information System (INIS)

Taylor, A.

1981-10-01

The ANL-Materials Science Division High Voltage Electron Microscope-Tandem Facility is a unique national research facility available to scientists from industry, universities, and other national laboratories, following a peer evaluation of their research proposals by the Facility Steering Committee. The principal equipment consists of a Kratos EM7 1.2-MV high voltage electron microscope, a 300-kV Texas Nuclear ion accelerator, and a National Electrostatics 2-MV Tandem accelerator. Ions from both accelerators are transmitted into the electron microscope through the ion-beam interface. Recent work at the facility is summarized

Accelerator mass spectrometry researches at NIES-TERRA

International Nuclear Information System (INIS)

Shibata, Yasuyuki; Yoneda, Minoru; Tanaka, Atsushi; Uehiro, Takashi; Morita, Masatoshi; Uchida, Masao; Yoshinaga, Jun

2003-01-01

In the AMS facility at the National Institute for Environmental Studies (NIES-TERRA; Tandem accelerator for Environmental Research and Radiocarbon Analysis), several research programs have been proceeded, including a program, called GC-AMS, for the compound-specific 14 C analysis in environmental samples

Representing Value as Digital Object: A Discussion of Transferability and Anonymity; Digital Library Initiatives of the Deutsche Forschungsgemeinschaft; CrossRef Turns One; Fermi National Accelerator Laboratory (Fermilab).

Science.gov (United States)

Kahn, Robert E.; Lyons, Patrice A.; Brahms, Ewald; Brand, Amy; van den Bergen, Mieke

2001-01-01

Includes four articles that discuss the use of digital objects to represent value in a network environment; digital library initiatives at the central public funding organization for academic research in Germany; an application of the Digital Object Identifier System; and the Web site of the Fermi National Accelerator Laboratory. (LRW)

Development of ADS virtual accelerator based on XAL

International Nuclear Information System (INIS)

Wang Pengfei; Cao Jianshe; Ye Qiang

2014-01-01

XAL is a high level accelerator application framework that was originally developed by the Spallation Neutron Source (SNS), Oak Ridge National Laboratory. It has an advanced design concept and has been adopted by many international accelerator laboratories. Adopting XAL for ADS is a key subject in the long term. This paper will present the modifications to the original XAL applications for ADS. The work includes a proper relational database schema modification in order to better suit the requirements of ADS configuration data, redesigning and re-implementing db2xal application, and modifying the virtual accelerator application. In addition, the new device types and new device attributes for ADS online modeling purpose are also described here. (authors)

Assessment of the adequacy of US accelerator technology for Department of Energy missions

International Nuclear Information System (INIS)

Gerry, E.T.; Mani, S.A.

1983-09-01

Accelerator technology has made enormous impact across a wide field of research, industrial, and commercial endeavor and new developments are projected to broaden this technology transfer and open up new applications not previously possible or economically attractive. At the same time, however, the broad multi-agency base of support for the development of accelerator technology has largely evaporated leaving the program with the Department of Energy (DOE) Office of Energy Research (OER) as the only major National effort not directed at specific narrow applications. In order to continue to reap the benefits and spin-offs from this area of technology, an expanded long-term funding committment is vigorously endorsed since there appear to be major payoff potential in several areas of national need. Three specific recommendations are made that would accelerate the projected benefits from accelerator technology. An expanded effort should be undertaken to develop the key technologies of high brightness, high current, large area, long life, reliable ion, electron and RF sources along with associated studies directed toward accelerator design optimization. A centralized computational facility with a dedicated staff and library of programs for simulation of accelerator phenomenology should be created similar to that for the magnetic fusion program. Advanced accelerator R and D should be funded at a steady level to support a long range accelerator applications program

National Wind Technology Center Site Environmental Assessment: Bird and Bat Use and Fatalities -- Final Report; Period of Performance: April 23, 2001 -- December 31, 2002

Energy Technology Data Exchange (ETDEWEB)

Schmidt, E.; Piaggio, A. J.; Bock, C. E.; Armstrong, D. M.

2003-01-01

This study was conducted to ascertain actual and potential impacts of wind turbines on populations of birds and bats at the National Wind Technology Center (NWTC) in northern Jefferson County, Colorado. The NWTC, which is part of the U.S. Department of Energy's National Renewable Energy Laboratory (NREL), is located on a mesa dominated by ungrazed grassland with isolated patches of ponderosa pine. Similar lands to the north and west are part of the city of Boulders open space system. Areas to the east and south are part of the Rocky Flats Environmental Technology Site.

Rayleigh-Taylor mixing with space-dependent acceleration

Science.gov (United States)

Abarzhi, Snezhana

2016-11-01

We extend the momentum model to describe Rayleigh-Taylor (RT) mixing driven by a space-dependent acceleration. The acceleration is a power-law function of space coordinate, similarly to astrophysical and plasma fusion applications. In RT flow the dynamics of a fluid parcel is driven by a balance per unit mass of the rates of momentum gain and loss. We find analytical solutions in the cases of balanced and imbalanced gains and losses, and identify their dependence on the acceleration exponent. The existence is shown of two typical sub-regimes of self-similar RT mixing - the acceleration-driven Rayleigh-Taylor-type mixing and dissipation-driven Richtymer-Meshkov-type mixing with the latter being in general non-universal. Possible scenarios are proposed for transitions from the balanced dynamics to the imbalanced self-similar dynamics. Scaling and correlations properties of RT mixing are studied on the basis of dimensional analysis. Departures are outlined of RT dynamics with space-dependent acceleration from canonical cases of homogeneous turbulence as well as blast waves with first and second kind self-similarity. The work is supported by the US National Science Foundation.

Proceedings of the meeting on the acceleration of polarized beams

International Nuclear Information System (INIS)

Takagi, Akira; Mori, Yoshiharu

1980-08-01

The project for accelerating polarized proton beam with the 12 GeV synchrotron in the National Laboratory for High Energy Physics was started in full scale, and the development of a polarized ion source of high intensity and the analysis of reduced polarization problem on the way to accelerate in the booster or the main ring have been carried out. On the other hand, with the cyclotrons in the Research Center for Nuclear Physics, Osaka University, and the Institute for Nuclear Research, University of Tokyo, and with the tandem machine in the Accelerator Center, Tsukuba University, polarized beams have already been accelerated, and the steady operations have been continued. Taking this opportunity, this study meeting was planned, considering that it is necessary to exchange informations among the researchers on polarized beam. It was the significant study meeting as unexpectedly many persons took part and the useful advices to the polarized beam project in this Laboratory were obtained. The construction of the preaccelerator for polarized protons was commenced in this year in the National Laboratory for High Energy Physics. In the proceedings, the introduction, the foreword, and eight papers are summarized. The progress of polarized beam researches in the world was mentioned in the introduction, and the project for proton acceleration in this Laboratory was explained in the foreword. (Kako, I.)

Accelerator-driven Medical Sterilization to Replace Co-60 Sources

Energy Technology Data Exchange (ETDEWEB)

Kroc, Thomas K. [Fermilab; Thangaraj, Jayakar C.T. [Fermilab; Penning, Richard T. [Fermilab; Kephart, Robert D. [Fermilab

2017-08-11

This report documents the results of a study prepared at the request of the Office of Radiological Security of the National Nuclear Security Administration (NNSA), as part of the Domestic Protect and Reduce mission by the Illinois Accelerator Research Center (IARC) of Fermi National Accelerator Laboratory. The study included a literature survey of over 80 relevant documents and articles including industry standards, regulatory documents, technical papers, a court case, previous task force reports and industry white papers. The team also conducted interviews or had conversations with over 40 individuals representing over a dozen organizations over the course of its 10-month program. This report summarizes our findings, addresses the specific questions posed to us by NNSA, and concludes with a list of actionable recommendations.

APT accelerator. Topical report

Energy Technology Data Exchange (ETDEWEB)

Lawrence, G.; Rusthoi, D. [comp.] [ed.

1995-03-01

The Accelerator Production of Tritium (APT) project, sponsored by Department of Energy Defense Programs (DOE/DP), involves the preconceptual design of an accelerator system to produce tritium for the nation`s stockpile of nuclear weapons. Tritium is an isotope of hydrogen used in nuclear weapons, and must be replenished because of radioactive decay (its half-life is approximately 12 years). Because the annual production requirements for tritium has greatly decreased since the end of the Cold War, an alternative approach to reactors for tritium production, based on a linear accelerator, is now being seriously considered. The annual tritium requirement at the time this study was undertaken (1992-1993) was 3/8 that of the 1988 goal, usually stated as 3/8-Goal. Continued reduction in the number of weapons in the stockpile has led to a revised (lower) production requirement today (March, 1995). The production requirement needed to maintain the reduced stockpile, as stated in the recent Nuclear Posture Review (summer 1994) is approximately 3/16-Goal, half the previous level. The Nuclear Posture Review also requires that the production plant be designed to accomodate a production increase (surge) to 3/8-Goal capability within five years, to allow recovery from a possible extended outage of the tritium plant. A multi-laboratory team, collaborating with several industrial partners, has developed a preconceptual APT design for the 3/8-Goal, operating at 75% capacity. The team has presented APT as a promising alternative to the reactor concepts proposed for Complex-21. Given the requirements of a reduced weapons stockpile, APT offers both significant safety, environmental, and production-fexibility advantages in comparison with reactor systems, and the prospect of successful development in time to meet the US defense requirements of the 21st Century.

Report of the workshop on accelerator-based atomic and molecular science

International Nuclear Information System (INIS)

Meyerhof, W.E.

1981-01-01

This Workshop, held in New London, NH on July 27-30, 1980, had a registration of 43, representing an estimated one-third of all principal investigators in the United States in this research subfield. The workshop was organized into 5 working groups for the purpose of (1) identifying some vital physics problems which experimental and theoretical atomic and molecular science can address with current and projected techniques; (2) establishing facilities and equipment needs required to realize solutions to these problems; (3) formulating suggestions for a coherent national policy concerning this discipline; (4) assessing and projecting the manpower situation; and (5) evaluating the relations of this interdisciplinary science to other fields. Recommedations deal with equipment and operating costs for small accelerator laboratories, especially at universities; instrumentation of ion beam lines dedicated to atomic and molecular science at some large accelerators; development of low-velocity, high charge-state ion sources; synchrotron light sources; improvement or replacement of tandem van de Graaff accelerators; high-energy beam lines for atomic physics; the needs for postdoctoral support in this subfield; new accelerator development; need for representatives from atomic and molecular science on program committees for large national accelerator facilities; and the contributions the field can make to applied physics problems

Photon and π"0 electroproduction at Jefferson Laboratory-Hall A

International Nuclear Information System (INIS)

Defurne, Maxime

2015-01-01

Defined in the mid 90's, the generalized parton distributions (GPDs) represent a higher level of information than the form factors and parton distribution functions: indeed they encapsulate the correlation between the fraction of longitudinal momentum and the transverse position of the partons inside the nucleon. Consequently we can access the distribution of the partons in the transverse plane according to their longitudinal momentum. Moreover we can derive the total angular orbital momentum of quarks thanks to Ji's sum rule. Experimentally, we access the GPDs through the study of deep exclusive processes (asymmetries, cross sections,...). A worldwide experimental program started in the early 2000's. This thesis presents two data analyses carried on two data sets from experiments running at Jefferson laboratory - Hall A in 2004 and 2010. From the 2004 data set, we have extracted unpolarized and polarized photon electroproduction cross sections. A careful study of the systematic errors has greatly improved the quality of the results. They seem to indicate the necessity to take into account target-mass and finite-t corrections up to twist-4. From the 2010 data set, we have performed the first separation of the longitudinal and transverse responses of neutral pion electroproduction. The results confirm the assumption of a significant contribution of the transverse response although kinematically suppressed with respect to the longitudinal response. These results of high precision validate the GPD approach and will allow to improve the existing models. (author) [fr

Accelerator Technology Program. Progress report, January-June 1980

International Nuclear Information System (INIS)

Knapp, E.A.; Jameson, R.A.

1980-03-01

The activities of Los Alamos Scientific Laboratory's (LASL) Accelerator Technology (AT) Division during the first six months of calendar 1980 are discussed. This report is organized around major projects of the Division, reflecting a wide variety of applications and sponsors. The first section summarizes progress on the Proton Storage Ring to be located between LAMPF and the LASL Pulsed Neutron Research facility, followed by a section on the gyrocon, a new type of high-power, high-efficiency radio-frequency (rf) amplifier. The third section discusses the racetrack microtron being developed jointly by AT Division and the National Bureau of Standards; the fourth section concerns the free-electron studies. The fifth section covers the radio-frequency quadrupole linear accelerator, a new concept for the acceleration of low-velocity particles; this section is followed by a section discussing heavy ion fusion accelerator development. The next section reports activities in the Fusion Materials Irradiation Test program, a collaborative effort with the Hanford Engineering Development Laboratory. The final section deals first with development of H - ion sources and injectors, then with accelerator instrumentation and beam dynamics

CAS course on Advanced Accelerator Physics in Warsaw

CERN Multimedia

CERN Accelerator School

2015-01-01

The CERN Accelerator School (CAS) and the National Centre for Nuclear Research (NCBJ) recently organised a course on Advanced Accelerator Physics. The course was held in Warsaw, Poland from 27 September to 9 October 2015.    The course followed an established format with lectures in the mornings and practical courses in the afternoons. The lecture programme consisted of 34 lectures, supplemented by private study, tutorials and seminars. The practical courses provided ‘hands-on’ experience of three topics: ‘Beam Instrumentation and Diagnostics’, ‘RF Measurement Techniques’ and ‘Optics Design and Corrections’. Participants selected one of the three courses and followed their chosen topic throughout the duration of the school. Sixty-six students representing 18 nationalities attended this course, with most participants coming from European counties, but also from South Korea, Taiwan and Russia. Feedback from th...

Search for baryon-number and lepton-number violating decays of Λ hyperons using the CLAS detector at Jefferson Laboratory

Science.gov (United States)

McCracken, M. E.; Bellis, M.; Adhikari, K. P.; Adikaram, D.; Akbar, Z.; Pereira, S. Anefalos; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dodge, G. E.; Dupre, R.; Alaoui, A. El; Fassi, L. El; Elouadrhiri, E.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fersch, R.; Filippi, A.; Fleming, J. A.; Garillon, B.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Mayer, M.; McKinnon, B.; Mestayer, M. D.; Meyer, C. A.; Mirazita, M.; Mokeev, V.; Moody, C. I.; Moriya, K.; Camacho, C. Munoz; Nadel-Turonski, P.; Net, L. A.; Niccolai, S.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Roy, P.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Skorodumina, Iu.; Sokhan, D.; Sparveris, N.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Tian, Ye; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

2015-10-01

We present a search for ten baryon number violating decay modes of Λ hyperons using the CLAS detector at Jefferson Laboratory. Nine of these decay modes result in a single meson and single lepton in the final state (Λ →m ℓ) and conserve either the sum or the difference of baryon and lepton number (B ±L ). The tenth decay mode (Λ →p ¯ π+ ) represents a difference in baryon number of two units and no difference in lepton number. We observe no significant signal and set upper limits on the branching fractions of these reactions in the range (4 - 200 )×10-7 at the 90% confidence level.

National Uranium Resource Evaluation, Tonopah quadrangle, Nevada

International Nuclear Information System (INIS)

Hurley, B.W.; Parker, D.P.

1982-04-01

The Tonopah Quadrangle, Nevada, was evaluated using National Uranium Resource Evaluation criteria to identify and delineate areas favorable for uranium deposits. Investigations included reconnaissance and detailed surface geologic and radiometric studies, geochemical sampling and evaluation, analysis and ground-truth followup of aerial radiometric and hydrogeochemical and stream-sediment reconnaissance data, and subsurface data evaluation. The results of these investigations indicate environments favorable for hydroallogenic uranium deposits in Miocene lacustrine sediments of the Big Smoky Valley west of Tonopah. The northern portion of the Toquima granitic pluton is favorable for authigenic uranium deposits. Environments considered unfavorable for uranium deposits include Quaternary sediments; intermediate and mafic volcanic and metavolcanic rocks; Mesozoic, Paleozoic, and Precambrian sedimentary and metasedimentary rocks; those plutonic rocks not included within favorable areas; and those felsic volcanic rocks not within the Northumberland and Mount Jefferson calderas

Deadline pressure and human error: a study of human failures on a particle accelerator at Brookhaven National Laboratory

International Nuclear Information System (INIS)

Tiagha, E.A.

1982-01-01

The decline in industrial efficiency may be linked to decreased reliability of complex automatic systems. This decline threatens the viability of complex organizations in industrialized economies. Industrial engineering techniques that minimize system failure by increasing the reliability of systems hardware are well developed in comparison with those available to reduce human operator errors. The problem of system reliability and the associated costs of breakdown can be reduced if we understand how highly skilled technical personnel function in complex operations and systems. The purpose of this research is to investigate how human errors are affected by deadline pressures, technical communication and other socio-dynamic factors. Through the analysis of a technologically complex particle accelerator prototype at Brookhaven National Laboratory, two failure mechanisms: (1) physical defects in the production process and (2) human operator errors were identified. Two instruments were used to collect information on human failures: objective laboratory data and a human failure questionnaire. The results of human failures from the objective data were used to test for the deadline hypothesis and also to validate the human failure questionnaire. To explain why the human failures occurred, data were collected from a four-part, closed choice questionnaire administered to two groups of scientists, engineers, and technicians, working together against a deadline to produce an engineering prototype of a particle accelerator

CERN accelerator school: Introductory course in Poland

CERN Document Server

2006-01-01

For the first time since the CERN Accelerator School (CAS) was set up, the 'Introduction to Accelerator Physics' course was held in Zakopane, Poland. This course was organised together with the National Atomic Energy Agency, Warsaw, and the AGH University of Science and Technology, Cracow, and was held from 1-13 October 2006 at the foot of the Tatra Mountains. The course was very well attended with 113 participants representing 26 different nationalities. Although most of the participants originated from Europe, some students came from countries as far away as Canada, China, India and North America. The intensive programme comprised 35 lectures, 3 seminars given by local Polish lecturers, 5 tutorials where the students were split into four groups, a poster session where students could present their own work and 7 hours of guided and private study. The participants appreciated these study periods, which encouraged collaboration and knowledge-sharing in solving problems and gave them the opportunity to get t...

New heavy-ion accelerator facility at Oak Ridge

International Nuclear Information System (INIS)

Stelson, P.H.

1974-01-01

Funds were obtained to establish a new national heavy-ion facility to be located at Oak Ridge. The principal component of this facility is a 25-MW tandem designed specifically for good heavy-ion acceleration, which will provide high quality beams of medium weight ions for nuclear research by itself. The tandem beams will also be injected into ORIC for additional energy gain, so that usable beams for nuclear physics research can be extended to about A = 160. A notable feature of the tandem is that it will be of the ''folded'' type, in which both the negative and positive accelerating tubes are contained in the same column. The accelerator system, the experimental lay-out, and the time schedule for the project are discussed

The present situation and prospect of industrial irradiation accelerator industry in China

International Nuclear Information System (INIS)

Zhao Wenyan; Wang Chuanzhen; Hou Fuzhen

2005-01-01

Accelerator technology and the machines are an important part of the nuclear technology and also are the system integration of modern science technology. The application of accelerator technology has made the important breakthrough in many science research fields, in the development course of particle physics, several milestone developments are closely related to accelerator developments. In 1960s, accelerators gradually transferred from the science research to the national economy and society application fields. In 1970s, accelerators applied in many fields involved the industry, medical hygiene, agriculture, environmental protection, and proceed the development of new technique, new craft, new product, and developed lots of newly arisen edge industries, such as the medical equipments, no damage examination, ion injecting, radiation processing. Now accelerators have become a firmly established industry. This paper primarily reviewed the application of industrial radiation accelerators by the 20 years developments of accelerators in China. (author)

Meeting the nation's environmental restoration and waste management challenges through the accelerated development of innovative technologies: A report on the DOIT initiative

International Nuclear Information System (INIS)

Prestwich, S.; Chee, T.

1994-01-01

New environmental technologies are needed to meet the Nation's environmental restoration and waste management challenges. However, in the past environmental technology development and commercialization process has been hampered by the absence of critical intergovernmental linkages and broad public acceptability. If the Nation can create cooperative linkages among levels of government and stakeholders, there is a tremendous opportunity not only to accelerate the pace of site cleanups but also to capture a larger share of the growing international market for remediation and waste management technologies. Recognizing this opportunity not only to accelerate the pace of site cleanups but also to capture a larger share of the growing international market for remediation and waste management technologies. Recognizing this opportunity, western governors and the U.S. Departments of Defense, Interior, Energy, and U.S. Environmental Protection Agency have established a partnership to test ways to expedite the deployment and testing of innovative cleanup technologies. This partnership, which was formalized through the creation of the Federal Advisory Committee to Develop On-Site Innovative Technologies (the DOIT initiative), will soon test models for speeding up the deployment, testing, evaluation, and commercialization of environmental technologies at selected demonstration sites primarily in the western United States. This evaluation process will be pursued in a manner that poses no additional risks to the environment, encourages innovative public participation, and helps ensure financial feasibility, insurability, and eventual commercialization of new technologies

Recircular accelerator to proton ocular therapy

International Nuclear Information System (INIS)

Rabelo, Luisa A.; Campos, Tarcisio P.R.

2013-01-01

Proton therapy has been used for the treatment of Ocular Tumors, showing control in most cases as well as conservation of the eyeball, avoiding the enucleation. The protons provide higher energetic deposition in depth with reduced lateral spread, compared to the beam of photons and electrons, with characteristic dose deposition peak (Bragg peak). This technique requires large particle accelerators hampering the deployment a Proton Therapy Center in some countries due to the need for an investment of millions of dollars. This study is related to a new project of an electromagnetic unit of proton circular accelerator to be coupled to the national radiopharmaceutical production cyclotrons, to attend ocular therapy. This project evaluated physical parameters of proton beam circulating through classical and relativistic mechanical formulations and simulations based on an ion transport code in electromagnetic fields namely CST (Computer Simulation Technology). The structure is differentiated from other circular accelerations (patent CTIT/UFMG NRI research group/UFMG). The results show the feasibility of developing compact proton therapy equipment that works like pre-accelerator or post-accelerator to cyclotrons, satisfying the interval energy of 15 MeV to 64 MeV. Methods of reducing costs of manufacture, installation and operation of this equipment will facilitate the dissemination of the proton treatment in Brazil and consequently advances in fighting cancer. (author)

Recircular accelerator to proton ocular therapy

Energy Technology Data Exchange (ETDEWEB)

Rabelo, Luisa A.; Campos, Tarcisio P.R., E-mail: luisarabelo88@gmail.com, E-mail: tprcampos@pq.cnpq.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear

2013-07-01

Proton therapy has been used for the treatment of Ocular Tumors, showing control in most cases as well as conservation of the eyeball, avoiding the enucleation. The protons provide higher energetic deposition in depth with reduced lateral spread, compared to the beam of photons and electrons, with characteristic dose deposition peak (Bragg peak). This technique requires large particle accelerators hampering the deployment a Proton Therapy Center in some countries due to the need for an investment of millions of dollars. This study is related to a new project of an electromagnetic unit of proton circular accelerator to be coupled to the national radiopharmaceutical production cyclotrons, to attend ocular therapy. This project evaluated physical parameters of proton beam circulating through classical and relativistic mechanical formulations and simulations based on an ion transport code in electromagnetic fields namely CST (Computer Simulation Technology). The structure is differentiated from other circular accelerations (patent CTIT/UFMG NRI research group/UFMG). The results show the feasibility of developing compact proton therapy equipment that works like pre-accelerator or post-accelerator to cyclotrons, satisfying the interval energy of 15 MeV to 64 MeV. Methods of reducing costs of manufacture, installation and operation of this equipment will facilitate the dissemination of the proton treatment in Brazil and consequently advances in fighting cancer. (author)

High average power linear induction accelerator development

International Nuclear Information System (INIS)

Bayless, J.R.; Adler, R.J.

1987-07-01

There is increasing interest in linear induction accelerators (LIAs) for applications including free electron lasers, high power microwave generators and other types of radiation sources. Lawrence Livermore National Laboratory has developed LIA technology in combination with magnetic pulse compression techniques to achieve very impressive performance levels. In this paper we will briefly discuss the LIA concept and describe our development program. Our goals are to improve the reliability and reduce the cost of LIA systems. An accelerator is presently under construction to demonstrate these improvements at an energy of 1.6 MeV in 2 kA, 65 ns beam pulses at an average beam power of approximately 30 kW. The unique features of this system are a low cost accelerator design and an SCR-switched, magnetically compressed, pulse power system. 4 refs., 7 figs

Electron-Ion Collider: The next QCD frontier. Understanding the glue that binds us all

Energy Technology Data Exchange (ETDEWEB)

Accardi, A. [Hampton University, Hampton, VA (United States); Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Albacete, J.L. [Universite Paris-Sud 11, CNRS/IN2P3, IPNO, Orsay (France); Anselmino, M. [Torino University (Italy); INFN, Torino (Italy); Armesto, N. [University of Santiago de Campostela, Santiago de Compostela (Spain); Aschenauer, E.C.; Burton, T.; Fazio, S.; Hao, Y.; Lamont, M.A.C.; Lee, J.H.; Lee, Y.; Litvinenko, V.; Ludlam, T.W.; Ptitsyn, V.; Qiu, J.W.; Roser, T.; Toll, T.; Trbojevic, D.; Ullrich, T.; Venugopalan, R.; Vigdor, S. [Brookhaven National Laboratory, Upton, NY (United States); Bacchetta, A. [University of Pavia, Pavia (Italy); Boer, D. [University of Groningen, Groningen (Netherlands); Brooks, W.K.; Hakobyan, H.; Kopeliovich, B. [Universidad Tecnica Federico Santa Maria, Valparaiso (Chile); Chang, N.B.; Huang, M. [Shandong University, Shandong (China); Deng, W.T. [Frankfurt University, FIAS, Frankfurt (Germany); Shandong University, Shandong (China); Deshpande, A.; Kumar, K. [Stony Brook University, Stony Brook, NY (United States); Diehl, M. [DESY, Hamburg (Germany); Dumitru, A.; Jalilian-Marian, J. [Baruch College, CUNY, New York, NY (United States); Dupre, R.; Sabatie, F. [Centre de Saclay, CEA, Gif-sur-Yvette (France); Ent, R.; Guzey, V.; Hutton, A.; Lin, F.L.; McKeown, R.; Morozov, V.S.; Nadel-Turonski, P.; Prokudin, A.; Weiss, C.; Zhang, Y.H. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Gao, H. [Duke University, Durham, NC (United States); Hasch, D. [INFN, LNF, Frascati (Italy); Holt, R. [Argonne National Laboratory, Argonne, IL (United States); Horn, T. [The Catholic University of America, N.E. Washington, DC (United States); Hyde, C. [Old Dominion University, Norfolk, VA (United States); Klein, S.; Sichtermann, E.; Yuan, F. [Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Kovchegov, Y. [The Ohio State University, Columbus, OH (United States); Kumericki, K. [University of Zagreb, Zagreb (Croatia); Lappi, T.; Paukkunen, H. [University of Jyvaskyla, Jyvaskyla (Finland); Levin, E.M. [Tel Aviv University, Tel Aviv (Israel); Universidad Tecnica Federico Santa Maria, Valparaiso (Chile); Marquet, C. [CERN, Geneva (Switzerland); Meziani, Z.E.; Metz, A. [Temple University, Philadelphia, PA (United States); Milner, R. [Massachusetts Institute of Technology, Cambridge, MA (United States); Mueller, A.H. [Columbia University, New York, NY (US); Mueller, B. [Brookhaven National Laboratory, Upton, NY (US); Duke University, Durham, NC (US); Mueller, D. [Ruhr-University Bochum, Bochum (DE); Qian, X. [California Institute of Technology, Pasadena, CA (US); Ramsey-Musolf, M. [University of Massachusetts at Amherst, Amherst, MA (US); Sassot, R. [University of Buenos Aires, Buenos Aires (AR); Schnell, G. [University of Basque Country, Bilbao (ES); Schweitzer, P. [University of Connecticut, Storrs, CT (US); Stratmann, M.; Vogelsang, W. [University of Tuebingen, Tuebingen (DE); Strikman, M. [Pennsylvania State University, Philadelphia, PA (US); Sullivan, M. [Stanford Linear Accelerator Center, Menlo Park, CA (US); Taneja, S. [Dalhousie University, Halifax, Nova Scotia (CA); Stony Brook University, Stony Brook, NY (US); Xiao, B.W. [Central China Normal University, Wuhan, Hubei (CN); Zheng, L. [Brookhaven National Laboratory, Upton, NY (US); Central China Normal University, Wuhan, Hubei (CN)

2016-09-15

This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics over the past decades and, in particular, the focused ten-week program on ''Gluons and quark sea at high energies'' at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them. It has been benefited profoundly from inputs by the users' communities of BNL and JLab. This White Paper offers the promise to propel the QCD science program in the US, established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier. (orig.)

Use of heavy ion accelerators in fusion reactor-related radiation-damage studies

International Nuclear Information System (INIS)

Taylor, A.; Dobson, D.A.

1974-01-01

The heavy-ion accelerator has become an important tool in the study of the fundamentals of radiation damage in fission- and fusion-reactor materials. Present facilities for such studies within the Materials Science Division at Argonne National Laboratory are provided by two complementary accelerator systems. Examples of the work carried out are discussed

Research on accelerator-driven transmutation and studies of experimental facilities

Energy Technology Data Exchange (ETDEWEB)

Takizuka, Takakazu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

1997-11-01

JAERI is carrying out R and Ds on accelerator-driven transmutation systems under the national OMEGA Program that aims at development of the technology to improve efficiency and safety in the final disposal of radioactive waste. Research facilities for accelerator-driven transmutation experiments are proposed to construct within the framework of the planned JAERI Neutron Science Project. This paper describes the features of the proposed accelerator-driven transmutation systems and their technical issues to be solved. A research facility plan under examination is presented. The plan is divided in two phases. In the second phase, technical feasibility of accelerator-driven systems will be demonstrated with a 30-60 MW experimental integrated system and with a 7 MW high-power target facility. (author)

Space-charge effects on bunching of electrons in the CEBAF injector

International Nuclear Information System (INIS)

Liu, H.

1997-01-01

The main injector for the 4 GeV CEBAF accelerator at Thomas Jefferson national accelerator facility was designed to deliver simultaneously three CW electron beams for nuclear physics research. The maximum design current for a single beam from the injector is 100 μA, or 0.2 pC per microbunch at a repetition rate of 499 MHz. It was found through computer simulation that space charge even at a subpicocoulomb level can spoil the bunching of electrons significantly, and some unexpected phenomena observed experimentally could be explained accordingly. This problem arises because of the low-momentum tilt allowed for bunching to preserve low-momentum spread. In this paper, we analyze in detail the space-charge effects on bunching of electrons with the CEBAF injector as an example. Conditions for effective matching of longitudinal phase space in the presence of space charge are discussed. (orig.)

Defect Detection in Superconducting Radiofrequency Cavity Surface Using C + + and OpenCV

Science.gov (United States)

Oswald, Samantha; Thomas Jefferson National Accelerator Facility Collaboration

2014-03-01

Thomas Jefferson National Accelerator Facility (TJNAF) uses superconducting radiofrequency (SRF) cavities to accelerate an electron beam. If theses cavities have a small particle or defect, it can degrade the performance of the cavity. The problem at hand is inspecting the cavity for defects, little bubbles of niobium on the surface of the cavity. Thousands of pictures have to be taken of a single cavity and then looked through to see how many defects were found. A C + + program with Open Source Computer Vision (OpenCV) was constructed to reduce the number of hours searching through the images and finds all the defects. Using this code, the SRF group is now able to use the code to identify defects in on-going tests of SRF cavities. Real time detection is the next step so that instead of taking pictures when looking at the cavity, the camera will detect all the defects.

76 FR 76048 - National Oil and Hazardous Substances Pollution Contingency Plan; National Priorities List...

Science.gov (United States)

2011-12-06

..., mercury, and selenium) and one semi-volatile organic compound (SVOC, pentachlorophenol) exceeded their... Marine of Port Arthur Superfund Site AGENCY: Environmental Protection Agency. ACTION: Direct final rule... Deletion of the State Marine of Port Arthur (SMPA) Superfund Site located in Port Arthur, Texas (Jefferson...

The Radiological Research Accelerator Facility

International Nuclear Information System (INIS)

Hall, E.J.

1992-05-01

The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which is used to generate a variety of well-characterized radiation beams for research in radiobiology, radiological physics, and radiation chemistry. It is part of the Center for Radiological Research (CRR) -- formerly the Radiological Research Laboratory (RRL) -- of Columbia University, and its operation is supported as a National Facility by the US Department of Energy (DOE). As such, RARAF is available to all potential users on an equal basis, and scientists outside the CRR are encouraged to submit proposals for experiments at RARAF. The operation of the Van de Graaff is supported by the DOE, but the research projects themselves must be supported separately. Experiments performed from May 1991--April 1992 are described

Tiara. Education and training in science of accelerators

International Nuclear Information System (INIS)

Falcon Cabrera, S.; Obradors Campos, D.; Marco Arboli, M.

2013-01-01

CIEMAT is participating in the European project TIARA (Test Infrastructure and Accelerator Research Area), whose main objective is to facilitate and optimize the effort in research and development in the area of science and technology of the accelerators in Europe. It is intended to integrate the infrastructures of r and d in this field, both national and international, in a way sustainable, complementary and well coordinated. The study presented by way of comparative European, exposes a series of parameters to assess the capabilities of each member country. (Author)

The aerogel threshold Cherenkov detector for the high momentum spectrometer in Hall C at Jefferson lab

International Nuclear Information System (INIS)

Razmik Asaturyan; Rolf Ent; Howard Fenker; David Gaskell; Garth Huber; Mark Jones; David Mack; Hamlet Mkrtchyan; Bert Metzger; Nadia Novikoff; Vardan Tadevosyan; William Vulcan; Stephen Wood

2004-01-01

We describe a new aerogel threshold Cherenkov detector installed in the HMS spectrometer in Hall C at Jefferson Lab. The Hall C experimental program in 2003 required an improved particle identification system for better identification of π/K/p, which was achieved by installing an additional threshold Cherenkov counter. Two types of aerogel with n = 1.03 and n = 1.015 allow one to reach ∼10 -3 proton and 10 -2 kaon rejection in the 1-5 GeV/c momentum range with pion detection efficiency better than 99% (97%). The detector response shows no significant position dependence due to a diffuse light collection technique. The diffusion box was equipped with 16 Photonis XP4572 PMT's. The mean number of photoelectrons in saturation was ∼16 and ∼8, respectively. Moderate particle identification is feasible near threshold

Performance Testing of Jefferson Lab 12 GeV Helium Screw Compressors

Science.gov (United States)

Knudsen, P.; Ganni, V.; Dixon, K.; Norton, R.; Creel, J.

2015-08-01

Oil injected screw compressors have essentially superseded all other types of compressors in modern helium refrigeration systems due to their large displacement capacity, reliability, minimal vibration, and capability of handling helium's high heat of compression. At the present state of compressor system designs for helium refrigeration systems, typically two-thirds of the lost input power is due to the compression system. It is important to understand the isothermal and volumetric efficiencies of these machines to help properly design the compression system to match the refrigeration process. It is also important to identify those primary compressor skid exergetic loss mechanisms which may be reduced, thereby offering the possibility of significantly reducing the input power to helium refrigeration processes which are extremely energy intensive. This paper summarizes the results collected during the commissioning of the new compressor system for Jefferson Lab's (JLab's) 12 GeV upgrade. The compressor skid packages were designed by JLab and built to print by industry. They incorporate a number of modifications not typical of helium screw compressor packages and most importantly allow a very wide range of operation so that JLab's patented Floating Pressure Process can be fully utilized. This paper also summarizes key features of the skid design that allow this process and facilitate the maintenance and reliability of these helium compressor systems.

Accelerator-control-system interface for intelligent power supplies

International Nuclear Information System (INIS)

Cohen, S.

1992-01-01

A number of high-current high-precision magnet power supplies have been installed at the proton storage ring at the Los Alamos National Laboratory Accelerator Complex. The units replace existing supplies, powering large dipole magnets in the ring. These bending magnets require a high-current supply that is precise and stable. The control and interface design for these power supplies represents a departure from all others on-site. The supplies have sophisticated microprocessor control on-board and communicate with the accelerator control system via RS-422 (serial communications). The units, built by Alpha Scientific Electronics, Hayward, CA use a high-level ASCII control protocol. The low-level ''front-end'' software used by the accelerator control system has been written to accommodate these new devices. They communicate with the control system through a terminal server port connected to the site-wide ethernet backbone. Details of the software implementation for the analog and digital control of the supplies through the accelerator control system will be presented

Installation, tests and start up of the Tandetron positive ions accelerator

International Nuclear Information System (INIS)

Valdovinos A, M.A.; Hernandez M, V.

2000-01-01

The National Institute of Nuclear Research acquired a Positive ions accelerator type Tandetron 2MV of the Dutch Company High Voltage Engineering, Europe B.V. (H.V.E.E.) which was installed in the building named Irradiator Nave which is occupied by the Gamma irradiator and the Pelletron accelerator. Starting from the accelerator selection it was defined the conditions required for the operation of this as well as: electric feeding, water quality and quantity, air compressed, temperature, humidity, etc.; as well as the necessary modifications of the installation area. (Author)

Accelerator School Success

CERN Multimedia

2004-01-01

Accelerator specialists don't grow on trees: training them is the job of the CERN Accelerator School (CAS). Group photo during visit to the Daresbury Laboratory. CAS and the CCLRC Daresbury Laboratory jointly organised a specialised school on Power Converters in Warrington, England from 12-18 May 2004. The last CAS Power Converter course was in 1990, so there was plenty of ground to cover. The challenging programme proposed a review of the state of the art and the latest developments in the field, including 30 hours of tuition. The school also included a visit to the CCLRC Daresbury laboratory, a one-day excursion to Liverpool and Chester and a themed (Welsh medieval) dinner at the school's closure. A record attendance of 91 students of more than 20 different nationalities included not only participants from Europe and North America but also from Armenia, Taiwan, India, Turkey, Iran and for the first time, fee-paying students from China and Australia. European industry showed a welcome and solid interest in...

Accelerator technology program. Progress report, January-June 1981

International Nuclear Information System (INIS)

Knapp, E.A.; Jameson, R.A.

1982-05-01

This report covers the activities of Los Alamos National Laboratory's Accelerator Technology Division during the first 6 months of calendar 1981. We discuss the Division's major projects, which reflect a variety of applications and sponsors. The varied technologies concerned with the Proton Storage ring are concerned with the Proton Storage Ring are continuing and are discussed in detail. For the racetrack microtron (RTM) project, the major effort has been the design and construction of the demonstration RTM. Our development of the radio-frequency quadrupole (RFQ) linear accelerator continues to stimulate interest for many possible applications. Frequent contacts from other laboratories have revealed a wide acceptance of the RFQ principle in solving low-velocity acceleration problems. In recent work on heavy ion fusion we have developed ideas for funneling beams from RFQ linacs; the funneling process is explained. To test as many aspects as possible of a fully integrated low-energy portion of a Pion generator for Medical Irradiation (PIGMI) Accelerator, a prototype accelerator was designed to take advantage of several pieces of existing accelerator hardware. The important principles to be tested in this prototype accelerator are detailed. Our prototype gyrocon has been extensively tested and modified; we discuss results from our investigations. Our work with the Fusion Materials Irradiation Test Facility is reviewed in this report

Multi-MW accelerator target material properties under proton irradiation at Brookhaven National Laboratory linear isotope producer

Science.gov (United States)

Simos, N.; Ludewig, H.; Kirk, H.; Dooryhee, E.; Ghose, S.; Zhong, Z.; Zhong, H.; Makimura, S.; Yoshimura, K.; Bennett, J. R. J.; Kotsinas, G.; Kotsina, Z.; McDonald, K. T.

2018-05-01

The effects of proton beams irradiating materials considered for targets in high-power accelerator experiments have been studied using the Brookhaven National Laboratory's (BNL) 200 MeV proton linac. A wide array of materials and alloys covering a wide range of the atomic number (Z) are being scoped by the high-power accelerator community prompting the BNL studies to focus on materials representing each distinct range, i.e. low-Z, mid-Z and high-Z. The low range includes materials such as beryllium and graphite, the midrange alloys such as Ti-6Al-4V, gum metal and super-Invar and finally the high-Z range pure tungsten and tantalum. Of interest in assessing proton irradiation effects are (a) changes in physiomechanical properties which are important in maintaining high-power target functionality, (b) identification of possible limits of proton flux or fluence above which certain materials cease to maintain integrity, (c) the role of material operating temperature in inducing or maintaining radiation damage reversal, and (d) phase stability and microstructural changes. The paper presents excerpt results deduced from macroscopic and microscopic post-irradiation evaluation (PIE) following several irradiation campaigns conducted at the BNL 200 MeV linac and specifically at the isotope producer beam-line/target station. The microscopic PIE relied on high energy x-ray diffraction at the BNL NSLS X17B1 and NSLS II XPD beam lines. The studies reveal the dramatic effects of irradiation on phase stability in several of the materials, changes in physical properties and ductility loss as well as thermally induced radiation damage reversal in graphite and alloys such as super-Invar.

A new AMS facility at Inter University Accelerator Centre, New Delhi

Science.gov (United States)

Kumar, Pankaj; Chopra, S.; Pattanaik, J. K.; Ojha, S.; Gargari, S.; Joshi, R.; Kanjilal, D.

2015-10-01

Inter University Accelerator Centre (IUAC), a national facility of government of India, is having a 15UD Pelletron accelerator for multidisciplinary ion beam based research programs. Recently, a new accelerator mass spectrometry (AMS) facility has been developed after incorporating many changes in the existing 15UD Pelletron accelerator. A clean chemistry laboratory for 10Be and 26Al with all the modern facilities has also been developed for the chemical processing of samples. 10Be measurements on sediment samples, inter laboratory comparison results and 26Al measurements on standard samples are presented in this paper. In addition to the 10Be and 26Al AMS facilities, a new 14C AMS facility based on a dedicated 500 kV tandem ion accelerator with two cesium sputter ion sources, is also being setup at IUAC.

Biological assessments for the low energy demonstration accelerator, 1996

Energy Technology Data Exchange (ETDEWEB)

Cross, S.

1997-03-01

This report discusses the biological impact to the area around the Los Alamos National Laboratory of the Low Energy Demonstration Accelerator. In particular the impact to the soils, water quality, vegetation, and wildlife are discussed.

Modification of the CEBAF transport dipoles for energy upgrade considerations

International Nuclear Information System (INIS)

D. Bullard; L. Harwood; T. Hiatt; J. Karn; E. Martin; W. Oren; C. Rode; K. Sullivan; R. Wines; M. Wiseman

1999-01-01

The CEBAF accelerator at the Thomas Jefferson National Accelerator Facility contains 415 resistive dipoles in the recirculation arcs and transport lines. These dipoles were originally designed and magnetically mapped to support the operation of the accelerator at 6 GeV. Recent interests in upgrading the CEBAF energy beyond 6 GeV prompted a study into operating the dipoles beyond their design limits. Finite element modeling was performed to quantify saturation effects at higher currents and to test simple modifications to improve magnetic performance. For confirmation, various steps were prototyped and magnetically measured. Measurement results agreed with finite element models and showed that saturation could be reduced to manageable levels. It was found that the most populous dipole families could be modified to reach twice their design field with minimal cost and effort. At these higher fields, the magnets operate at a reasonable thermal state with minimal saturation losses a nd little degradation in field quality. Work continues on studying the smaller population of dipoles to determine their performance at higher fields

Operational status of the Brookhaven National Laboratory Accelerator Test Facility

International Nuclear Information System (INIS)

Batchelor, K.; Ben-Zvi, I.; Chou, T.S.; Los Alamos National Lab., NM; Princeton Univ., NJ

1989-01-01

Design and operation of a 50 MeV Electron Linear Accelerator utilizing a low emittance (γ var epsilon = 5 to 10 mm-mrad) radio frequency gun operating at an output energy of 5 MeV and a charge of 1 nC is described. Design calculations and early radio frequency measurements and operational experience with the electron gun utilizing a dummy copper cathode in place of the proposed photocathode emitter are given. 6 refs., 9 figs., 1 tab

Opportunities and challenges of a low-energy positron source in the LERF

Science.gov (United States)

Benson, Stephen; Wojtsekhowski, Bogdan; Vlahovic, Branislav; Golge, Serkan

2018-05-01

Though there are many applications of low energy positrons, many experiments are source limited. Using the LERF accelerator at the Thomas Jefferson National Accelerator Facility, it is possible to build a high brightness source of very low-energy positrons. The accelerator requirements are well within the capabilities of the installed hardware. The accelerator can produce 120 kW of beam with a beam energy of up to 170 MeV. For these experiments, we only need run at up to 120 MeV. The gamma-to-positron converter must be able to absorb 20% of the beam power that the linac delivers. At this low an energy the converter, though challenging, is possible. The transport of the low energy positrons from the production target to the next stage, where the energy is reduced even further, must have a very large acceptance to be able to efficiently transport the flux of positrons from the positron production target to the moderator. We propose to accomplish such a transport by means of a guiding solenoidal field with a novel endcap design. In this presentation, we will present the proposed schemes necessary to realize such a high brightness positron source.

Measured Radiation and Background Levels During Transmission of Megawatt Electron Beams Through Millimeter Apertures

Energy Technology Data Exchange (ETDEWEB)

Alarcon, Ricardo [Arizona State University, Glendale, AZ (United States); Balascuta, S. [Arizona State University, Glendale, AZ (United States); Benson, Stephen V. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Bertozzi, William [Massachusetts Institute of Technology, Cambridge, MA (United States); Boyce, James R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Cowan, Ray [Massachusetts Institute of Technology, Cambridge, MA (United States); Douglas, David R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Evtushenko, Pavel [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Fisher, P. [Massachusetts Institute of Technology, Cambridge, MA (United States); Ihloff, Ernest E. [Hampton University, Hampton, VA (United States); Kalantarians, Narbe [Hampton University, Hampton, VA (United States); Kelleher, Aidan Michael [Massachusetts Institute of Technology, Cambridge, MA (United States); Krossler, W. J. [William and Mary College, Williamsburg, VA (United States); Legg, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Long, Elena [University of New Hampshire, Durham, NH (United States); Milner, Richard [Massachusetts Institute of Technology, Cambridge, MA (United States); Neil, George R. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Ou, Longwu [Massachusetts Institute of Technology, Cambridge, MA (United States); Schmookler, Barack Abraham [Massachusetts Institute of Technology, Cambridge, MA (United States); Tennant, Christopher D. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Tschalar, C. [Massachusetts Institute of Technology, Cambridge, MA (United States); Williams, Gwyn P. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhang, Shukui [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2013-11-01

We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-off, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW continuous-wave (CW) beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, multipactoring inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation when the machine is tuned for 130 MeV operation.

Plasma Desorption Mass Spectrometry using TANDEM accelerator in National Industrial Research Inst. of Nagoya

Energy Technology Data Exchange (ETDEWEB)

Mizota, Takeshi; Nakao, Setsuo; Niwa, Hiroaki; Saito, Kazuo [Particle Beam Sceince Laboratory, Multi-Function Material Science Department, National Industrial Research Inst. of Nagoya, Nagoya (Japan)

2001-02-01

Plasma Desorption Mass Spectrometry (PDMS) analysis was studied using TANDEM accelerator. The heavy ions of MeV range emit the secondary ions of atoms, molecules, polymers and clusters from the irradiated samples without destruction. The analysis system of PDMS designed and set-up using a mass spectrometer of Time of Flight and the TANDEM accelerator. The system performance was tested for C-60 fullerene on the surface of the samples using 11.2 MeV {sup 28}Si beams produced by the TANDEM accelerator of 1.7MV. The result shows that the hydrogen and hydrocarbons can be analyzed in the range of 1amu unit. The resolution (M/{delta}M) of the Mass Spectrometry system is confirmed to be about 1000 from the separation of the 720 and 721amu peaks, which is attributed to the C-60 fullerene including {sup 13}C atoms. (H. Katsuta)

Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case

Energy Technology Data Exchange (ETDEWEB)

Ye, Zhihong; Sato, Nobuo; Allada, Kalyan; Liu, Tianbo; Chen, Jian-Ping; Gao, Haiyan; Kang, Zhong-Bo; Prokudin, Alexei; Sun, Peng; Yuan, Feng

2017-04-01

© 2017 The Authors Future experiments at the Jefferson Lab 12 GeV upgrade, in particular, the Solenoidal Large Intensity Device (SoLID), aim at a very precise data set in the region where the partonic structure of the nucleon is dominated by the valence quarks. One of the main goals is to constrain the quark transversity distributions. We apply recent theoretical advances of the global QCD extraction of the transversity distributions to study the impact of future experimental data from the SoLID experiments. Especially, we develop a simple strategy based on the Hessian matrix analysis that allows one to estimate the uncertainties of the transversity quark distributions and their tensor charges extracted from SoLID data simulation. We find that the SoLID measurements with the proton and the effective neutron targets can improve the precision of the u- and d-quark transversity distributions up to one order of magnitude in the range 0.05 < x < 0.6.

Beam position reconstruction for the g2p experiment in Hall A at Jefferson lab

Science.gov (United States)

Zhu, Pengjia; Allada, Kalyan; Allison, Trent; Badman, Toby; Camsonne, Alexandre; Chen, Jian-ping; Cummings, Melissa; Gu, Chao; Huang, Min; Liu, Jie; Musson, John; Slifer, Karl; Sulkosky, Vincent; Ye, Yunxiu; Zhang, Jixie; Zielinski, Ryan

2016-02-01

Beam-line equipment was upgraded for experiment E08-027 (g2p) in Hall A at Jefferson Lab. Two beam position monitors (BPMs) were necessary to measure the beam position and angle at the target. A new BPM receiver was designed and built to handle the low beam currents (50-100 nA) used for this experiment. Two new super-harps were installed for calibrating the BPMs. In addition to the existing fast raster system, a slow raster system was installed. Before and during the experiment, these new devices were tested and debugged, and their performance was also evaluated. In order to achieve the required accuracy (1-2 mm in position and 1-2 mrad in angle at the target location), the data of the BPMs and harps were carefully analyzed, as well as reconstructing the beam position and angle event by event at the target location. The calculated beam position will be used in the data analysis to accurately determine the kinematics for each event.

Experimental study of the A(e,e'π+) reaction on 1H, 2H, 12C, 27Al, 63Cu, and 197Au

International Nuclear Information System (INIS)

Qian, X.; Gao, H.; Kramer, K.; Horn, T.; Clasie, B.; Seely, J.; Arrington, J.; El Fassi, L.; Zheng, X.; Asaturyan, R.; Mkrtchyan, H.; Navasardyan, T.; Tadevosyan, V.; Benmokhtar, F.; Boeglin, W.; Markowitz, P.; Bosted, P.; Bruell, A.; Chudakov, E.; Ent, R.

2010-01-01

Cross sections for the 1 H(e,e ' π + )n process on 1 H, 2 H, 12 C, 27 Al, 63 Cu, and 197 Au targets were measured at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) to extract nuclear transparencies. Data were taken from Q 2 =1.1-4.7 GeV 2 for a fixed center-of-mass energy of W=2.14 GeV. The ratio of σ L and σ T was extracted from the measured cross sections for 1 H, 2 H, 12 C, and 63 Cu targets at Q 2 =2.15 and 4.0 GeV 2 , allowing for additional studies of the reaction mechanism. In this article, we present the experimental setup and the analysis of the data in detail, including systematic uncertainty studies. Differential cross sections and nuclear transparencies as a function of the pion momentum at different values of Q 2 are presented. Our results are consistent with the predicted early onset of color transparency in mesons. Global features of the data are discussed and the data are compared with model calculations for the 1 H(e,e ' π + )n reaction from nuclear targets.

Technical meeting to 'Review of national programmes on fast reactors and accelerator driven systems (ADS)'. Working material

International Nuclear Information System (INIS)

2002-01-01

The 35th Annual Meeting of the Technical Working Group on Fast Reactors TWG-FR, previously International Working Group on Fast Reactors (IWG-FR, created in 1967), was hosted by the Forschungszentrum Karlsruhe (FZK) and was attended by TWG-FR members and advisers from the following Member States: Brazil, China, France, Germany, India, Japan, the Republic of Kazakhstan, the Republic of Korea, the Russian Federation, and the United States of America. The objectives of the meeting were: to exchange information on the national programmes on Fast Reactors (FR) and Accelerator Driven Systems (ADS); to review the progress since the 34th TWG-FR Annual Meeting, including the status of the actions; to consider meeting arrangements for 2002 and 2003; to review the Agency's co-ordinated research activities in the field of FRs and ADS, as well as co-ordination of the TWG-FR's activities with other organizations

Technical meeting to 'Review of national programmes on fast reactors and accelerator driven systems (ADS)'. Working material

Energy Technology Data Exchange (ETDEWEB)

NONE

2002-07-01

The 35th Annual Meeting of the Technical Working Group on Fast Reactors TWG-FR, previously International Working Group on Fast Reactors (IWG-FR, created in 1967), was hosted by the Forschungszentrum Karlsruhe (FZK) and was attended by TWG-FR members and advisers from the following Member States: Brazil, China, France, Germany, India, Japan, the Republic of Kazakhstan, the Republic of Korea, the Russian Federation, and the United States of America. The objectives of the meeting were: to exchange information on the national programmes on Fast Reactors (FR) and Accelerator Driven Systems (ADS); to review the progress since the 34th TWG-FR Annual Meeting, including the status of the actions; to consider meeting arrangements for 2002 and 2003; to review the Agency's co-ordinated research activities in the field of FRs and ADS, as well as co-ordination of the TWG-FR's activities with other organizations.

High-current beam transport in electrostatic accelerator tubes

International Nuclear Information System (INIS)

Ramian, G.; Elais, L.

1987-01-01

The UCSB Free Electron Laser (FEL) has successfully demonstrated the use of a commercial 6 megavolt electrostatic accelerator as a high current beam source in a recirculating configuration. The accelerator, manufactured by National Electrostatics Corp. (NEC), Middleton WI, uses two standard high gradient accelerator tubes. Suppression of ion multiplication was accomplished by NEC with apertures and a shaped electrostatic field. This field shaping has fortuitously provided a periodically reversing radial field component with sufficient focusing strength to transport electron beams of up to 3 Amps current. Present two-stage FEL work requires a 20 Amp beam and proposed very high voltage FEL designs require currents as high as 100 Amps. A plan to permit transport of such high current beams by the addition of solenoidal focussing elements is described

Accelerator technology program. Status report, July-December 1982

International Nuclear Information System (INIS)

Jameson, R.A.

1984-05-01

Major projects of the Los Alamos National Laboratory's Accelerator Technology Division are discussed, covering activities that occurred during the last six months of calendar 1982. The first sections report highlights in beam dynamics, accelerator inertial fusion, radio-frequency structure development, the racetrack microtron, CERN high-energy physics experiment NA-12, and high-flux radiographic linac study. Next we report on selected proton Storage Ring activities that have made significant progress during this reporting period, followed by an update on the free electron laser. The Fusion Materials Irradiation Test Facility work is discussed next, then progress on the klystron development project and on the gyrocon project. The activities of the newly formed Theory and Simulation Group are outlined. The last section covers activities concerning the accelerator test stand for the neutral particle beam program

Physical properties of a linear accelerator-based stereotactic installed at national cancer institute

International Nuclear Information System (INIS)

Attala, E.M.; Deiab, N.A.; Elawady, R.A.

2005-01-01

The purpose of this paper is to present the dosimetry and mechanical accuracy of the first dedicated Siemens PRIMUS M6/6ST linear accelerator-based Stereotactic installed in National Cancer Institute for stereotactic radiosurgery and radiotherapy (SRS/SRT). The data were obtained during the installation, acceptance test procedure, and commissioning of the unit. The Primus M6/6ST has a single 6-MV beam with the same beam characteristics as that of the mother unit, the Siemens. The dosimetric data were taken using pin point ion chamber. The cone sizes vary from 12.5 to 40.0 mm diameter. The mechanical stability of the entire system was verified. The variations in isocenter position with table, gantry, and collimator rotation were found to be < 0.5 mm with a compounded accuracy of < or = 1.0 mm. The beam profiles of all cones in the x and y directions were within +/- 0.5 mm and match with the physical size of the cone. The basic dosimetry parameters such as tissue maximum ratio (TMR), off-axis ratio (OAR) and cone factor needed for patient treatment were evaluated. The mechanical and dosimetric characteristics including dose linearity of this unit are presented and found to be suitable for SRS/SRT. The difficulty in absolute dose measurement for small cone is discussed

Professor Kodi Husimi promoted accelerator projects

International Nuclear Information System (INIS)

Kikuchi, Ken

2009-01-01

The main aim of my article is to describe how deeply Professor Husimi devoted himself to promote large accelerator projects in Japan, as the establishment of National Laboratory for High Energy Physics (KEK), Photon Factory and TRISTAN, in which I myself was deeply involved. In addition, some topics related that I was a student of Professor Husimi are also reported. (author)

CAS Accelerator Physics held in Erice, Italy

CERN Multimedia

CERN Accelerator School

2013-01-01

The CERN Accelerator School (CAS) recently organised a specialised course on Superconductivity for Accelerators, held at the Ettore Majorana Foundation and Centre for Scientific Culture in Erice, Italy from 24 April-4 May, 2013.   Photo courtesy of Alessandro Noto, Ettore Majorana Foundation and Centre for Scientific Culture. Following a handful of summary lectures on accelerator physics and the fundamental processes of superconductivity, the course covered a wide range of topics related to superconductivity and highlighted the latest developments in the field. Realistic case studies and topical seminars completed the programme. The school was very successful with 94 participants representing 23 nationalities, coming from countries as far away as Belorussia, Canada, China, India, Japan and the United States (for the first time a young Ethiopian lady, studying in Germany, attended this course). The programme comprised 35 lectures, 3 seminars and 7 hours of case study. The case studies were p...

Radiological Research Accelerator Facility

International Nuclear Information System (INIS)

Goldhagen, P.; Marino, S.A.; Randers-Pehrson, G.; Hall, E.J.

1986-01-01

The Radiological Research Accelerator Facility (RARAF) is based on a 4-MV Van de Graaff accelerator, which can be used to generate a variety of well-characterized radiation beams for research in radiobiology and radiological physics. It is part of the Radiological Research Laboratory (RRL), and its operation is supported as a National Facility by the US Department of Energy. RARAF is available to all potential users on an equal basis, with priorities based on the recommendations of a Scientific Advisory Committee. Facilities and services are provided to users, but the research projects themselves must be supported separately. This chapter presents a brief description of current experiments being carried out at RARAF and of the operation of the Facility from January through June, 1986. Operation of the Facility for all of 1985 was described in the 1985 Progress Report for RARAF. The experiments described here were supported by various Grants and Contracts from NIH and DOE and by the Statens Stralskyddsinstitut of Sweden

Optimizing Centrifugal Barrel Polishing For Mirror Finish SRF Cavity And RF Tests At Jefferson Lab

International Nuclear Information System (INIS)

Palczewski, Ari; Geng, Rongli; Tian, Hui

2012-01-01

We performed Centrifugal Barrel Polishing (CBP) on a 1.3 GHz fine grain TESLA single cell cavity and 1.5 GHz fine grain CEBAF high gradient superconducting radio frequency (SRF) single cell cavity following a modified recipe originally developed at Fermi National Accelerator Lab (FNAL). We were able to obtain a mirror like surface similar to that obtained at FNAL, while reducing the number of CBP steps and total processing time. This paper will discuss the change in surface and subsequent cavity performance post CBP, after a 800 C bake (no pre-bake chemistry) and minimal controlled electro-polishing (10 micron). In addition to Q vs. E ACC thermometry mapping with preheating characteristics and optical inspection of the cavity after CBP will also be shown.

Simulations of a FIR Oscillator with Large Slippage parameter at Jefferson Lab for FIR/UV pump-probe experiments

International Nuclear Information System (INIS)

Benson, Stephen V.; Campbell, L. T.; McNeil, B.W.T.; Neil, George R.; Shinn, Michelle D.; Williams, Gwyn P.

2014-01-01

We previously proposed a dual FEL configuration on the UV Demo FEL at Jefferson Lab that would allow simultaneous lasing at FIR and UV wavelengths. The FIR source would be an FEL oscillator with a short wiggler providing diffraction-limited pulses with pulse energy exceeding 50 microJoules, using the exhaust beam from a UVFEL as the input electron beam. Since the UV FEL requires very short pulses, the input to the FIR FEL is extremely short compared to a slippage length and the usual Slowly Varying Envelope Approximation (SVEA) does not apply. We use a non-SVEA code to simulate this system both with a small energy spread (UV laser off) and with large energy spread (UV laser on)