The Thomas Jefferson National Accelerator Facility (Jefferson Lab) is a user facility for scientists worldwide. Its primary mission is to conduct basic research of the atom�s nucleus at the quark level.
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The Continuous Electron Accelerator Facility, CEBAF, located at the Thomas Jefferson National Accelerator Facility, is devoted to the investigation of the electromagnetic structure of mesons, nucleons, and nuclei using high energy, high duty-cycle electro...
National Technical Information Service (NTIS)
The Thomas Jefferson National Accelerator Facility (Jefferson Lab) is in the process of building a 1 kW free-electron laser operates at 3 microns. The details of the accelerator driver are given in other papers in these proceedings. The optical cavity con...
A Free Electron Laser (FEL) called the IR Demo is operational as a user facility at Thomas Jefferson National Accelerator Facility in Newport News, Virginia, USA. It utilizes a 48 MeV superconducting accelerator that not only accelerates the beam but also...
Thomas Jefferson National Accelerator Facility 12000 Jefferson Avenue Newport News, VA 23606 Weizhen Mao at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) is a distributed sys� tem using client of reengineering ...
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Thomas Jefferson National Accelerator Facility (Jefferson Lab) is a U.S. Department of Energy Facility (1) conducting Nuclear Physics experiments that currently have data collection rates of up to 20 MB / second. Future experiments, however, are expected ...
of the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility the Jefferson Science Associates, LLC, (JSA) operates the Thomas Jefferson National Ac� celerator Facility Kees de ...
The Continuous Electron Beam Accelerator Facility (CEBAF) has been successfully carrying out hadronic physics studies since 1996 at the Thomas Jefferson National Accelerator Facility (JLab) in Virginia, USA. The characteristics of this electron beam, toge...
The Thomas Jefferson National Accelerator Facility (Jefferson Lab) has developed a set of Work Smart Standards for the Lab. The effort incorporated the Lab's performance-based contract into the Necessary and Sufficient (N&S) Standards identification proce...
The Department of Energy's Thomas Jefferson National Accelerator Facility. Sam Garcia, Robert Linza, and Daniel Meagher. Jacobs Engineering ...
NASA Website
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is funded by the Office of Science for the United States Department of Energy (DoE) with strong support from the City of Newport News, the Commonwealth of Virginia, and the United States Congress. As a user facility for scientists ...
at the Thomas Jefferson National Accelerator Facility using the Common Device (CDEV) [1] framework on top at Thomas Jefferson National Accelerator Facility'', Proceedings of PAC 1997, Vancouver. [5] R. Dickson Response Matrices for On�line Orbit and Energy Correction at ...
Accurate measurement of path length and path length changes versus momentum (M(sub 56)) are critical for maintaining minimum beam energy spread in the CEBAF (Continuous Electron Beam Accelerator Facility) accelerator at the Thomas Jefferson National Accel...
* J. Sage, M. H. Bickley, K. S. White, Jefferson Lab, Newport News, VA 23606, USA Abstract The Thomas Jefferson National Accelerator Facility (Jefferson Lab) control system uses a nameserver to reduce system The Jefferson Lab Accelerator, Cryogenics ...
at the Thomas Jefferson National Accelerator Facility faces a number of challenges common to facilities managing Accelerator Control System Software At Jefferson Lab #1; #1;#1; #1; S. Schaffner, T. Larrieu, JLAB, Newport News, VA and installation of software. 1 BACKGROUND ...
. Smith for the CLAS Collaboration Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue of this asymmetry. We will review the current experimental program to study DVCS at Jefferson Lab. Recent high toward probing GPD's at Jefferson Lab. There are two ...
electroproduction of pseudoscalar mesons. The experiment was done in collaboration with the Thomas Jefferson)X at High Q2 . User Group Meeting, Thomas Jefferson National Accelerator Facility, Newport News, VA, August
The Detector Group at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) and the Biology, Physics and Applied Sciences Departments at the College of William and Mary are collaborating on the development of a miniature dual modality SPECT-C...
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-a (0.61) prototype, el...
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 nece...
advantage of the cheaper airfares in and out of the Baltimore airport. ...... Thomas Jefferson National Accelerator Facility (a.k.a. Jefferson Lab), a Department of Energy ...... PM) with the purchase of a $3.60 drink. ...
a Thomas Jefferson National Accelerator Facility, 12000 Jefferson Avenue MS 6a, Newport News, VA 23606 USA-doped InAs wafer irradiated by a femtosecond free-electron laser (FEL) at the Thomas Jefferson National Berkeley Na- tional Laboratory) and DE-AC05-84-ER40150 (Thomas ...
Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, MA 02139 b Thomas Jefferson. The Thomas Jefferson National Accelerator Facility and the MIT Laboratory for Nuclear Science have undertaken Research Association (SURA) operates the Thomas Jefferson National ...
... power directed energy weapon is the proposed 100 kW upgrade of the Thomas Jefferson National Accelerator Facility's Free Electron Laser (FEL). ...
DTIC Science & Technology
a Tata Institute of Fundamental Research, Bombay, India, akr@tifr.res.in, b Thomas Jefferson National Accelerator Facility, Newport News, VA, USA, ...
On May 14, 2001, the Thomas Jefferson National Accelerator Facility (JLAB) conducted a planned liquid helium release into its accelerator tunnel to study the effectiveness of the JLAB facility to vent the helium and therefore limit the oxygen deficiency h...
The Continuous Electron Beam Accelerator Facility (CEBAF) was built in Newport News, Virginia, between 1987 and 1995 and is a new basic research laboratory christened the Thomas Jefferson National Accelerator Facility (Jefferson Lab). Jefferson ...
DOE Information Bridge
Thomas Jefferson National Accelerator Facility (Jefferson Lab) is a U.S. Department of Energy Facility [1] conducting Nuclear Physics experiments that currently have data collection rates of up to 20 MB / second. Future experiments, however, are expected to greatly exceed these rates. Post ...
Energy Citations Database
It is often the belief that electron accelerators are clean machines, producing little or no measurable removable contamination. However, at the Thomas Jefferson National Accelerator Facility (Jefferson Lab), a 200 {micro}A continuous wave, 4 GeV electron accelerator, there ...
�84�ER40150 Abstract Field�Programmable Gate Arrays (FPGAs) have provided Thomas Jefferson National Accelerator Facility (Jefferson Lab) with versatile VME�based data acquisition and control interfaces parameters and options that are not readily available commercially. Jefferson Lab has ...
Updated results of the experiment E94-107 hypernuclear spectroscopy in Hall A of the Thomas Jefferson National Accelerator Facility (Jefferson Lab), are presented. The experiment provides high resolution spectra of excitation energy for 12?B, 16?N, and 9?Li hypernuclei obtained by electroproduction of strangeness. ...
NASA Astrophysics Data System (ADS)
storage ring at Cornell, the CEBAF machine at the Thomas Jefferson Na- tional Accelerator Facility (CHESS), the Cornell Laboratory of Elementary Particle Physics (LEPP), and the Thomas Jefferson National (Jefferson Laboratory), and LEP at CERN, all of which are driven by SC radio-frequency ...
Universities Research Association (SURA) operates the Thomas Jefferson National Accelerator Facility for DOE AND THE GENERALIZED POLARIZABILITIES OF THE NUCLEON H.FONVIEILLE, for the Jefferson Lab Hall A Collaboration, Jefferson Lab and MIT-Bates. This contribution summarizes the results ...
Maintenance, repair, and upgrades to the Thomas Jefferson National Accelerator Facility, a DOE laboratory located in Newport News, VA, USA, is based upon a two-week run cycle followed by a one-shift maintenance period. The rationale for this approach will be presented including a brief look at the maintenance funding, support staff, ...
There is an active program of few-body form factor measurements in Hall A of Thomas Jefferson National Accelerator Facility (Jefferson Laboratory). Recent measurements of the deuteron elastic electric, A(Q2), and magnetic, B(Q2), structure functions will be presented. Planned measurements of the form factors of 3He ...
. Dong, R. Flood, C. Hovater, J. Musson Thomas Jefferson National Accelerator Facility, Newport News, VA Monitor (BCM) system at Jefferson Lab. It is a versatile general�purpose digital signal processing board. The application programs are loaded to the DSP via Spectrum Digital DS510PP_PLUS JTAG emulator. 2.2 ...
40506�0055, USA J.P.Chen, E. Chudakov, S. Nanda, A. Saha Thomas Jefferson National Accelerator Facility, 23668, USA ABSTRACT As part of the spin physics program at Jefferson Laboratory (JLab), a M�ller, such as Jefferson Laboratory (JLab), require precise measure� ments of electron beam ...
The Thomas Jefferson National Accelerator Facility (Jefferson Lab) comprises a 5 GeV continuous electron beam accelerator (CEBAF) delivering beam to three experimental halls, and a kilowatt range tunable free electron laser (FEL), currently being upgraded to a 10 kW machine. The progression ...
With the successful completion of the main accelerator in 1994 the alignment emphasis at the Thomas Jefferson National Accelerator Facility (formerly CEBAF) switched to the continuing installation and upgrades in the three experimental halls. This presentation examines the techniques used in completing the CEBAF ...
The Thomas Jefferson National Accelerator Facility, Jefferson Lab, is planning an upgrade of the CEBAF accelerator from a maximum energy of 6 GeV to 12 GeV and from 3 to 4 experimental halls. This paper will discuss the plans for upgrading the energy of the machine which requires improvements ...
The Thomas Jefferson National Accelerator Facility (Jefferson Lab) has been funded by the US Navy to build an infra-red FEL driven by an energy-recovering compact SRF-based linear accelerator. The machine is to produce a 1 kW IR photon beam. The Jefferson Lab ...
Coherent THz pulses are being produced at several facilities using relativistic electrons from linear accelerators. The THz pulses produced at the Brookhaven accelerator have pulse energies exceeding 50 {micro}J and reach a frequency of 2 THz. The high repetition rate of the Jefferson Lab ...
Superconducting radiofrequency (SRF) technology using niobium accelerating cavities was first applied at large scale in the recirculating electron linear accelerator CEBAF--the Continuous Electron Beam Accelerator Facility in Newport News, Virginia, USA, at what is now called Thomas Jefferson ...
A prototype 100mA injector is presently being designed and manufactured jointly between Thomas Jefferson National Accelerator Facility (JLab) and Advanced Energy Systems (AES). This paper discusses the physics optimization and performance of the injector ...
New measurements of the high energy deuteron photodisintegration differential cross section were made at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia. Two experiments were performed. Experiment E96-003 was performed in expe...
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.
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.
This letter briefly discusses the history and implications of national laboratory name changes with a focus on accelerator facilities. (AIP) {copyright} {ital 1997 American Institute of Physics}
Excellent vacuum is essential for long photocathode lifetimes in DC high voltage photoelectron guns. Vacuum Research at Thomas Jefferson National Accelerator Facility has focused on characterizing the existing vacuum systems at the CEBAF polarized photoin...
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 (Je...
The Machine Control Center (MCC) at Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) was initially constructed in the early 1990s and based on proven technology of that era. Through our experience over the last 15 years and in our pla...
The Beam Scraping Monitor (BSM) is used to detect small amounts of beam loss in Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF). The BSM acts as an early warning system that alerts CEBAF operators when the beam loss exceeds 10 to 20 ...
Data on real-photon induced reactions have been taken using the Tagged Photon Facility (TPF) and the Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility (JLab) during the first year of running in Hall B. These data ...
The CEBAF accelerator at Thomas Jefferson National Accelerator Facility (Jefferson Lab) uses a continuous electron beam with up to 800 kilowatts of average beam power. The laboratory beam containment policy requires that in the event of an errant beam striking a beam blocking device, the beam ...
We review plans for future fixed target lepton- and hadron-scattering facilities, including the 12 GeV upgraded CEBAF accelerator at Jefferson Lab, neutrino beam facilities at Fermilab, and the antiproton PANDA facility at FAIR. We also briefly review recent theoretical developments which will ...
Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) currently has a maximum beam energy of 6 GeV. The 12 GeV Upgrade Project will double the existing energy and is currently scheduled for completion in 2014. This doubling of energy requires modifications to the beam transport system which includes the ...
In this paper the current plans for the control system for Thomas Jefferson National Accelerator Facility`s (Jefferson Lab`s) Infrared Free Electron Laser (FEL) are presented. The goals for the FEL control system are fourfold: (1) to use EPICS and EPICS compatible tools, (2) to use VME and Industry Pack (IPs) ...
Two types of dipole magnets were simulated and designed for the Thomas Jefferson National Accelerator Facility FEL upgrade. The magnets are to operate in series with a common power supply, and to provide ~0.01% accuracy of the field amplitude and field integral over a large aperture.
Experimental results for photo- and electro-production of open strangeness from the Thomas Jefferson National Accelerator Facility are discussed. The results are from work completed by mid-2003 on elementary $KY$ production, nuclear targets, and the exotic $\\Theta^+$ state. It is shown how the increases in intensity and precision of ...
A control system for Hall B at the Thomas Jefferson National Accelerator Facility is being developed within the framework of the Experimental Physics and Industrial Control System (EPICS). The Hall B equipment currently under EPICS control include numerous beam line devices, high voltage supplies, detector gas systems, and safety ...
Jefferson Labs (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 accelera...
The CLAS collaboration in Hall B at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) has a broad scientific program. Recent results on the main topics are presented. These concern the electromagnetic excitation of nucleon resonances, the measurement of inclusive spin structure functions in the ...
Thomas Jefferson National Accelerating Facility (Jefferson Lab) is producing 24 Superconducting Radio Frequency (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. Each of the ...
This is the website for the science education section of the Thomas Jefferson National Accelerator Facility, also called the Jefferson Lab. It is dedicated to helping K�12 teachers and motivating students in mathematics and science. It contains a teacher�s resource page, a student zone, a puzzles and games page ...
The authors describe the physics program and the experimental equipment of the CEBAF Large Acceptance Spectrometer, CLAS. The spectrometer is located in Hall B, one of the three experimental areas at the Continuous Electron Beam Accelerator Facility (CEBAF) operated by the Thomas Jefferson National Accelerator ...
Thomas Jefferson National Accelerator Facility (Jefferson Lab; formerly known as CEBAF), operates a 4 GeV, 200 {micro}A continuous wave (CW) electron accelerator that re-circulates the beam five times through two superconducting 400 MeV linacs. Electrons can be extracted from any of the five ...
At Thomas Jefferson National Accelerator Facility, accelerator operators perform tasks in their areas of specialization in addition to their machine operations duties. One crucial area in which operators contribute is software development. Operators with programming skills are uniquely qualified to develop certain ...
The imminent commissioning of the Japan Proton Accelerator Research Complex (J-PARC) and the planned construction of the Facility for Antiproton and Ion Research (FAIR) will offer the opportunity to pursue a systematic program of high-precision and high-statistics studies in the field of hypernuclear physics. This subject will represent as well an ...
The Thomas Jefferson National Accelerator Facility (Jefferson Lab) has developed a set of Work Smart Standards for the Lab. The effort incorporated the Lab's performance-based contract into the Necessary and Sufficient (N and S) Standards identification process of the DOE. A rigorous protocol identified ...
The Thomas Jefferson National Accelerator Facility (Jefferson Lab) has developed a set of Work Smart Standards for the Lab. The effort incorporated the Lab`s performance-based contract into the Necessary and Sufficient (N and S) Standards identification process of the DOE. A rigorous protocol identified hazards in ...
The plans for upgrading the CEBAF accelerator at Jefferson Lab to 12 GeV are presented. The research program supporting that upgrade is illustrated with a few selected examples. The instrumentation under design to carry out that research program is discussed. Finally, a conceptual design of a future upgrade which combines a 25 GeV fixed-target ...
The plans for upgrading the CEBAF accelerator at Jefferson Lab to 12 GeV are presented. The research program supporting that upgrade are illustrated with a few selected examples. The instrumentation under design to carry out that research program is discussed. Finally, a conceptual design of a future upgrade which combines a 25 GeV fixed-target ...
Observing Session in West Jefferson, NC (22 guest with Anderson, SC. ... Location: West Jefferson, NC Retreat facility, West Jefferson, ...
In partnership with the US Navy, high-technology corporations, and research universities, Jefferson Lab is building a superconducting radio-frequency (SRF) accelerator-driven free-electron laser (FEL) and is outfitting an FEL user facility. This first fourth-generation light source - a 1kW, 3?m infrared (IR) laser - is the first step ...
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) ...
The Thomas Jefferson National Accelerator Facility (Jefferson Lab) houses a 4 GeV, 200 {micro}A continuous wave (CW) recirculating electron accelerator. This underground accelerator is made up of two superconducting linear accelerators (linacs), two ...
The Continuous Electron Accelerator Facility, CEBAF, is devoted to the investigation of the electromagnetic structure of mesons, nucleons, and nuclei using high energy and high duty-cycle and photon beams. The physics program and the experimental equipment at CEBAF will be described. Selected examples for the results obtained will be given. The ...
The Southeastern Universities Research Association (SURA) operates the Thomas Jefferson National Accelerator Facility (Jefferson Lab) for the United States Department of Energy. As a user facility for physicists worldwide, its primary mission is to conduct basic nuclear physics research of the ...
The mission of the Jefferson Lab Operations Group is to provide safe and efficient delivery of high quality electron beam for Jefferson Laboratory's nuclear and accelerator physics programs. The Operations staff must be able to setup, transport, maintain,...
Thomas Jefferson National Accelerator Facility's (Jefferson Lab) accelerator controls were initially implemented as a proprietary in-house system. During machine commissioning, problems were encountered leading to a decision to migrate to the Experimental Physics and Industrial ...
In light of the recent developments with the International Linear Collider (ILC), and the recommendation to utilize ''Cold'' technology for this future particle accelerator, this paper will present the lessons learned from the recently concluded Spallation Neutron Source (SNS) superconducting radio frequency (SRF) cryomodule production run ...
Anisotropic Clover Action Huey�Wen Lin #3; Thomas Jefferson National Accelerator Facility, Newport News, VA Facility, Newport News, VA 23606 In this work, we perform parameter tuning with dynamical anisotropic loop ratios and PCAC masses. We demonstrate that these ideas are equivalent to but more efficient than
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 ...
This paper reports on the magnetic field mapping performed on the HRS spectrometers of Hall A, which are of QQDQ type. The dipoles were measured with a set of Hall probes in the symmetry mid-plane. The quadrupoles were measured inside their whole volume by a set of axially segmented rotating coils. High accuracy has been reached in both cases. Dipoles and quadrupoles were measured for a set of ...
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. ...
At cryogenic temperatures (below 20 K), most of the existing lossy materials become non-lossy, requiring the development of a new materials effective in these conditions. Results of an effort to develop a cryogenically lossy materials based on the AlN matrix are presented in the paper. Hot pressing with a wide range of possible lossy second phases was tried, followed by complex permitivity ...
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 ...
We describe the design and commissioning of the photon tagging beamline installed in experimental Hall B at the Thomas Jefferson National Accelerator Facility. This system can tag photon energies over a range from 20% to 95% of the incident electron energy, and is capable of operation with beam energies up to 6.1 GeV. A single dipole ...
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 ...
The preliminary results are presented for Jefferson Lab experiment E02-104 which was performed in the CLAS detector at Thomas Jefferson National Accelerator Facility. During the experiment, data on semi-inclusive production of hadrons in deep-inelastic scattering of a lepton off nuclei were acquired. These data ...
Hadron physics has been an essential part of the physics program with the CLAS detector in experimental hall B at Thomas Jefferson National Accelerator Facility (Jefferson Lab). With the 12 GeV upgrade of the CEBAF machine, hadron physics in Hall B will be extended to a new domain of higher mass resonances and the ...
Electro- and photoproduction of {omega}(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 ...
Electro- and photoproduction of ?(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. ...
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 ...
A bunch length monitor for ultrashort (90 fs to 1 ps) electron bunches using a coherent synchrotron radiation detection techniques has been developed in a collaboration between the Thomas Jefferson National accelerator Facility (Jefferson Lab) and the University of Virginia. The noninvasive, high-resolution, ...
Jefferson Lab contributes to the Department of Energy mission to develop and operate major cutting-edge scientific user facilities. Jefferson Lab's CEBAF (Continuous Electron Beam Accelerator Facility) is a unique tool for exploring the transition between the regime where strongly ...
Magnetic measurements have been performed on the prototype dipole for the high power IR-FEL presently under construction at the Thomas Jefferson National Accelerator Facility. The optics-driven requirements for these magnets include low fields, large horizontal apertures, tight field homogeneity, absolute setability of core field & ...
The Continuous Electron Beam Accelerator Facility at Jefferson Lab in Newport News, Virginia, was the first large-scale deployment of superconducting radiofrequency (RF) technology, and was optimized for nuclear/high energy physics research. The success of this technology led to the creation of a Free Electron Laser (FEL) ...
The upcoming parity violating deep inelastic scattering (PVDIS) experiment E08-011 in Hall A at Thomas Jefferson National Accelerator Facility (Jefferson Lab) aims to measure a combination of the axial hadronic couplings of the electron with a factor of six improvement in precision over world data. Precise data for ...
Thomas Jefferson National Accelerating Facility, Jefferson Lab, is producing 24 Superconducting Radio Frequency (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 ...
The ?, or ``Cascade'' hyperon, is related to the proton by SU(3)F symmetry. This means that their properties are expected to be related to one another, as are the properties of their respective excited states. This hints at the possibility of using the excited states in the ? spectrum to learn more about the excited states of the nucleon, which are hard to isolate in the laboratory due to their ...
Experiment E02-0131 at Thomas Jefferson National Accelerator Facility (Jefferson Lab) will measure the neutron electric form factor GnE at the high four-momentum transfer values of Q^2 ~ 1.3, 2.4 and 3.4 (GeV/c)2 via a measurement of the cross section asymmetry A_T in the reaction ...
This chapter is a personal account of the initial planning and competition for a new laboratory, which eventually became known as the Thomas Jefferson National Accelerator Facility, with the official nickname "Jefferson Lab." The period covered starts as far back as 1964, with the introduction of quarks, and ...
Accurate measurement of path length and path length changes versus momentum (M{sub 56}) are critical for maintaining minimum beam energy spread in the CEBAF (Continuous Electron Beam Accelerator Facility) accelerator at the Thomas Jefferson National Accelerator Facility ...
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 ...
Studies of single spin asymmetries for pion electroproduction in semi-inclusive deep-inelastic scattering are presented using the polarized ~6 GeV electrons from at the Thomas Jefferson National Accelerator Facility (JLab) and the Continuous Electron Beam Accelerator Facility (CEBAF) Large ...
The CEBAF accelerator at JLab is fulfilling its scientific mission to understand how hadrons are constructed from the quarks and gluons of QCD, to understand the QCD basis for the nucleon-nucleon force, and to explore the transition from the nucleon-meson to a QCD description. Its success is based on the firm foundation of experimental and theoretical techniques developed ...
At Thomas Jefferson National Accelerator Facility (Jefferson Lab), the availability of the control system is crucial to the operation of the accelerator for experimental programs. Jefferson Lab's control system, uses 68040 based microprocessors running VxWorks, ...
Abstract The Continuous Electron Beam Accelerator Facility (CEBAF) recirculating accelerator at Jefferson Lab consists of two linacs carrying beam for up to five passes of acceleration. The design of this accelerator anticipated the onset of multipass beam break-up (BBU) at ...
The Software Controls Group at Thomas Jefferson National Accelerator Facility (Jefferson Lab) is responsible for slow controls for many Jefferson Lab facilities. The Experimental Physics and Industrial Control System (EPICS) is used as the basis of these control systems. ...
Jefferson Lab has a strong record of helping DOE achieve its science education and workforce development goals. The Lab works with the local community to enhance the quality of K-12 STEM education in the public schools. Jefferson Lab serves the nation by providing an educational pipeline for the country's brightest students at the high school and ...
Jefferson Lab is building a free-electron laser to produce tunable, continuous-wave (cw), kW-level light at 3-6 {mu}m wavelength. A superconducting accelerator will drive the laser, and a transport lattice will recirculate the beam back through the accelerator for energy recovery. Space charge in the injector and coherent synchrotron ...
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 ...
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 ...
The Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab is a $600M CW electron accelerator in Newport News, Virginia. The machine is a recirculating, superconducting 5-pass linac initially commissioned for 4 GeV with a maximum beam power of 1 MW. With improvements in our RF cavity performance and ...
Energen, Inc. has designed, built and demonstrated a fine tuning mechanism for superconducting radio frequency (SRF) cavities used in particle accelerators. This tuner is based on giant magnetostrictive materials being developed by Energen, Inc. Magnetostrictors elongate when exposed to a small magnetic field. This extension is reversible and repeatable enabling a wide range ...
The characteristics of the system of �SF� Sextupoles for the infrared Free Electron Laser Upgrade1 at the Thomas Jefferson National Accelerator Facility (JLab) are described. These eleven sextupoles possess a large field integral (2.15 T/m) with +/- 0.2%
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 ...
The focal plane polarimeter (FPP) for Hall A at the Thomas Jefferson National Accelerator Facility (TJNAF) is ready for experiments. The ability to calibrate the FPP on-site using elastic scattering of polarized electrons from an unpolarized hydrogen target is demonstrated. The ratio of the proton electric form factor to its magnetic ...
The first electroproduction experiment of a hypernucleus was undertaken at the Thomas Jefferson National Acceleration Facility. The (e,e'K+) reaction was used on a natC target resulting in the observation of the 12LB hypernucleus. The excitation spectrum is presented and discussed.
Terahertz (THz) radiation is generated by exciting an un-doped InAs wafer with a femtosecond free-electron laser (FEL) at the Thomas Jefferson National Accelerator Facility. A microwatt level of THz radiation is detected from the unbiased InAs emitter whe...
Terahertz (THz) radiation is generated by exciting an un-doped InAs wafer with a femtosecond free-electron laser (FEL) at the Thomas Jefferson National Accelerator Facility. A microwatt level of THz radiation is detected from the unbiased InAs emitter when it is excited with the femtosecond FEL pulses operated at a wavelength of 1.06 ...
The first measurements of the differential cross section from d((gamma),p)n up to 4.0 GeV were performed at the Thomas Jefferson National Accelerator Facility (TJNAF, formerly CEBAF). Bremsstrahlung photons from electron beam impinging on a copper radiato...
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 1057 MeV. This polarimeter was a prototype designed to measure G{sub E}{sup n}, the neutron electric form factor, at the Thomas Jefferson National Accelerator ...
We describe a procedure for the simulation of free-electron-laser (FEL) oscillators. The simulation uses a combination of the MEDUSA simulation code for the FEL interaction and the OPC code to model the resonator. The simulations are compared with recent observations of the oscillator at the Thomas Jefferson National Accelerator ...
PubMed
The HAPPEx-II experiment at Thomas Jefferson National Accelerator Facility measures the parity-violating helicity-correlated scattering asymmetry APV in elastic electron scattering from 1H and 4He. These measurements explore the strange quark contributions to the electric and magnetic vector form factors and of the nucleon. An ...
One transitional step for the development of a 1 MW power directed energy weapon is the proposed 100 kW upgrade of the Thomas Jefferson National Accelerator Facility's Free Electron Laser (FEL). To improve the performance of the FEL, the use of the step-t...
Photoproduction of phi mesons at photon energies below 2 GeV were measured at the CLAS detector in Hall B of Thomas Jefferson National Accelerator Facility. Preliminary differential cross sections are reported from the proton near threshold. The measurement are extended to the region in the variable t where production mechanisms ...
Tests of thin composition vacuum windows of the type used for the Tagger in Hall B at the Thomas Jefferson National Accelerator Facility are described. Three different tests have been performed. These include: (1) measurement of the deformation and durability of a window under long term (>8 years) almost continuous vacuum load, (2) ...
In June 1999 the Thomas Jefferson National Accelerator Facility (TJNAF) Cryogenic Systems Group had completed the design, fabrication, and commissioning of a cold compressor system capable of pumping 250 g/s of 2-K helium vapor to a pressure above 1 bar. ...
We describe the design of the SRF Energy-Recovering Linac (ERL) providing the CW electron drive beam at the Jefferson Lab UV FEL. Based on the same 135 MeV linear accelerator as � and sharing portions of the recirculator with � the Jefferson Lab 10 kW IR Upgrade FEL, the UV driver ERL uses a novel bypass geometry to provide ...
We describe the design of the SRF Energy-Recovering Linac (ERL) providing the CW electron drive beam at the Jefferson Lab UV FEL. Based on the same 135 MeV linear accelerator as and sharing portions of the recirculator with the Jefferson Lab 10 kW IR Upgrade FEL, the UV driver ERL uses a novel bypass geometry to provide transverse ...
The Spallation Neutron Source (SNS) requires 32 super conducting cryomodules to raise the beam energy of the accelerator to 1.3 GeV. Thomas Jefferson National Accelerator Facility (Jefferson Lab) has been contracted to build and deliver these cryomodules. The SNS cryomodules are being assembled ...
Jefferson Lab (JLab) is proposing JLAMP (JLab Amplifier), a 4th generation light source covering the 10-100 eV range in the fundamental mode with harmonics stretching towards the oxygen k-edge. The new photon science user facility will feature a two-pass superconducting LINAC to accelerate the electron beam to 600MeV at repetition ...
A Free Electron Laser (FEL) called the IR Demo is operational as a user facility at Thomas Jefferson National Accelerator Facility in Newport News, Virginia, USA. It utilizes a 48 MeV superconducting accelerator that not only accelerates the beam but also recovers about 80% ...
The CLAS detector is a large acceptance spectrometer located at the electron accelerator at Thomas Jefferson National Accelerator Facility. Production of K+ and K* mesons along with associated hyperons were measured using the CLAS detector at electron beam energies of 2.4-4.4 GeV. In addition, polarization transfer ...
The Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab can be described as a series of concatenated beamlines. Methods used to measure the Twiss parameters in closed orbit machines are not applicable in such open ended systems. We are using properly selected sets of real orbits in the ...
A totally home-made 9-cell TESLA type superconducting cavity is made at Peking University. The cavity fabrication is according to DESY specification. The cavity is made of high purity niobium from OTIC, Ningxia. The electron beam welding is carried out at Harbin Institute of Technology, Harbin. By the cooperation, the cavity is tested at Thomas Jefferson National ...
The nuclear physics experiments at the Thomas Jefferson National Accelerator Facility often require longitudinally polarized electrons to be simultaneously delivered to three experimental halls. The degree of longitudinal polarization to each hall varies as function of the accelerator settings, making it ...
DC high voltage photoemission electron guns with GaAs photocathodes have been used to produce polarized electron beams for nuclear physics experiments for about 3 decades with great success. In the late 1990s, Jefferson Lab adopted this gun technology for a free electron laser (FEL), but to assist with high bunch charge operation, considerably higher bias voltage is required ...
A reliability model for the Thomas Jefferson National Accelerator Facility (Jefferson Lab) 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 of the model's implementation allows rapid ``what if'' case ...
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 ...
The outline of this document is: Jefferson Lab; Collaboration, Capability Growth; 12GeV Energy Updgrade; Acceleration and Radiation in Vacuum; Superconducting Linear Collider and SRF Control; Other Initiatives: HELIOS and Biomedical Imaging; and Outlook.
The CLAS detector is located in Hall B at Thomas Jefferson National Accelerator Facility in Newport News, Virginia, USA. It is a multipurpose, large acceptance magnetic spectrometer instrumented with detector systems sensitive to charged and neutral particles. In addition to hosting electron scattering experiments, Hall B contains an ...
The commissioning and resulting capabilities of Hall A at the Thomas Jefferson National Accelerator Facility for performing coincidence experiments with a continuous-wave electron beam at energies of 0.8-6.0 GeV will be described. The facility consists of a pair of high-resolution magnetic spectrometers to detect ...
The commissioning and resulting capabilities of Hall A at the Thomas Jefferson National Accelerator Facility for performing coincidence experiments with a continuous wave electron beam at energies of 0.8--6.0 GeV will be described. The facility consists of a pair of high-resolution magnetic spectrometers to detect ...
The Continuous Electron Beam Accelerator Facility (CEBAF) at the Jefferson Laboratory (JLAB) is capable of accelerating e{sup -} to 6 GeV in energy. Presently CEBAF is being upgraded to a maximum energy of 12 GeV. In addition to e{sup -} scattering, the user community has expressed interest in performing e{sup +} ...
This paper describes the design of the new 12 GeV Upgrade Personnel Safety System (PSS) at the Thomas Jefferson National Accelerator Facility (TJNAF). The new PSS design is based on the implementation of systems designed to meet international standards IEC61508 and IEC 61511 for programmable safety systems. In order to meet the IEC ...
In this environmental assessment (EA), the US Department of Energy (DOE) reports the results of an analysis of the potential environmental impacts from a proposed change in operating parameters of the Continuous Electron Beam Accelerator Facility (CEBAF), and operation of the Free Electron Laser (FEL) facility beyond the initial ...
In the framework of the 12 GeV upgrade project for the Continuous Electron Beam Accelerator Facility (CEBAF) improvements are being made to refurbish cryomodules housing Thomas Jefferson National Accelerator Facility�s (JLab) original 5-cell cavities. Recently we have started to look into a ...
This paper will present the requirements and design of the Timing Synchronization System for the Continuous Electron Beam Accelerator Facility control system at Thomas Jefferson National Accelerator Facility. A clock module has been designed to reside in a VME crate with a master front-end ...
The Jefferson Laboratory's superconducting radiofrequency (srf) Continuous Electron Beam Accelerator Facility (CEBAF) provides multi-GeV continuous-wave (cw) beams for experiments at the nuclear and particle physics interface. CEBAF comprises two antiparallel linacs linked by nine recirculation beam lines for up to five passes. By the ...
The existing continuous electron beam accelerator facility (CEBAF) at Thomas Jefferson National Accelerator Facility (TJNAF) is a 5-pass, recirculating cw electron Linac operating at ~6 GeV and is devoted to basic research in nuclear physics. The 12 GeV CEBAF Upgrade is a $310 M project, ...
, USA M. Joyce, TJNAF, Newport News, VA 23606, USA Abstract At Thomas Jefferson National Accelerator in the day�to� day operation of the accelerator. Jefferson Lab is one of the few laboratories that utilizes the programs written by these operator�programmers, Jefferson Lab has improved ...
The Infrared Free Electron Laser being constructed at the Thomas Jefferson National Accelerator Facility will require a 42 MeV, 5 mA electron accelerator. The accelerator design requires a 10 MeV injector and a two pass 32 MeV linac, one pass for acceleration and one pass ...
Strangeness has been shown to be important for the understanding of the so-called missing resonances. Due to the scarce experimental data in strangeness photoproduction on the neutron, phenomenological models such as coupled-channels analyses resort to certain approximations that do not allow getting either accuracy or agreement between different analyses when extracting resonance parameters. ...
The Spin Asymmetries of the Nucleon Experiment (SANE) at the Thomas Jefferson Lab National Accelerator Facility measured inclusive double spin asymmetries by scattering longitudinally polarized electrons on a longitudinally and transversely polarized NH3 target. The measurements were done at momentum transfer of 2.5 <= Q^2 <= 6.5 ...
In this article, we report on on investigations of the in-medium meson-nucleon interaction for the ?, ?, and Ks0 mesons. Their in-medium cross sections and collisional widths can be measured by their absorption in a nucleus. In Hall B at the Thomas Jefferson National Accelerator Facility (JLab), the CLAS detector was used to study ...
The kW-class infrared (IR) free electron laser (FEL) at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) had the capability of producing intra-cavity Thomson scattering of the IR off the electron beam thus producing high average flux, sub-picosecond x-rays. We have measured these x-rays and ...
Fiducial volumes have been determined for photons detected in the electromagnetic calorimeters of the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. This work is part of a systematic study of neutral meson photoproduction from the proton and light nuclear targets over an incident ...
The Thomas Jefferson National Accelerator Facility, known as the Jefferson Lab, is funded by the Office of Science for the US Department of Energy. Its corresponding Web site and educational offerings include the interactive Element Hangman game. This simple exercise requires kids to enter the correct letters of an ...
In February 2006, Jefferson Laboratory in Newport News, VA, received � Critical Decision 1� (CD-1) approval to proceed with the engineering and design of the long anticipated upgrade to increase the beam energy of CEBAF, the Continuous Electron Beam Accelerator Facility, from 6 GeV to 12 GeV. This will require the installation ...
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 ...
In February 2006, Jefferson Laboratory in Newport News, VA, received ``Critical Decision 1'' (CD-1) approval to proceed with the engineering and design of the long anticipated upgrade to increase the beam energy of CEBAF, the Continuous Electron Beam Accelerator Facility, from 6 GeV to 12 GeV. This will require the installation of 10 ...
The (e,e'p) reaction has proven to be a useful tool for studying specific aspects of the nucleus. The Jefferson Lab continuous electron beam accelerator facility (CEBAF) along with the high resolution spectrometers in the Hall A end station allow this reaction to be studied in kinematics heretofore unaccessible. In this paper ...
The Thomas Jefferson National Accelerator Facility, a $600 million US Department of Energy national laboratory, serves basic science by carrying out a primary mission of nuclear and particle physics research. A technologically related secondary mission now also exists for Jefferson Lab: applied research to develop ...
The Thomas Jefferson National Accelerator Facility has experienced magnet overheating at high power. Overheating is caused by cooling water passages becoming plugged and is a direct result of the Dean Effect deposition of corrosion products suspended in the water. Salving simplified dynamic model equations of the flow in the magnet ...
An accelerator-based experiment was performed using the CEBAF accelerator of the Thomas Jefferson National Accelerator Facility to investigate a predicted sensitivity of the beam polarization to the vertical betatron orbit in the recirculation arcs. This is the first measurement of any such ...
The Machine Control Center at Jefferson Lab's Continuous Electron Beam Accelerator Facility was initially constructed in the early 1990s and based on proven technology of that era. Through our experience over the last 15 years and in our planning for the facilities 12 GeV upgrade we reevaluated the control ...
The Machine Control Center (MCC) at Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) was initially constructed in the early 1990s and based on proven technology of that era. Through our experience over the last 15 years and in our planning for the facility's 12 GeV upgrade we ...
We report longitudinal phase space measurements of short electron bunches at the 10kW Free-Electron Laser Facility at Jefferson Lab using broadband synchrotron radiation and a remotely controlled fast streak camera. Accurate measurements are possible because the optical transport system uses only reflective components that do not introduce dispersion. The ...
In the framework of the 12 GeV upgrade project for the Continuous Electron Beam Accelerator Facility (CEBAF) improvements are being made to refurbish cryomodules housing Thomas Jefferson National Accelerator Facilitys (JLab) original 5-cell cavities. Recently we have started to look into a ...
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 ...
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 ...
High Technology Systems (HTS) with sensitive surfaces, such as superconducting radio frequency (SRF) accelerating cavities, polarized electron sources (PES) for accelerators and many others, are prone to degradation when subjected to particulate or hydrocarbon contaminants. Particulate contamination control of SRF cavity surfaces and vacuum components have ...
The Time of Flight (TOF) system is a detection system within the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson National Accelerator Facility. CLAS, being a magnetic toroidal multi-gap spectrometer, is used in the detection of particles and their varying properties. Jefferson National ...
The first study of (e,e',K+) on carbon and aluminum was performed at Thomas Jefferson National Accelerator Facility (Jefferson Lab) using the Continuous Electron Beam Accelerator Facility (CEBAF). The scattered electron and electroproduced kaon were detected in ...
The original goal of this proposal was to study frozen spin polarized targets (HD target and other technologies) and produce a conceptual design report for the implementation of such a target in the HALL B detector of the Thomas Jefferson National Accelerator Facility (JLab). During the first two years of the proposal, we came to the ...
DRIVER ACCELERATOR DESIGN FOR THE 10 KW UPGRADE OF THE JEFFERSON LAB IR FEL D. Douglas, S. V, Newport News, VA23606, USA Abstract An upgrade of the Jefferson Lab IR FEL [1] is now un- der construction. It will provide 10 kW output light power in a wavelength range of 2�10 �m. The FEL will be driven by a modest
DRIVER ACCELERATOR DESIGN FOR THE 10 KW UPGRADE OF THE JEFFERSON LAB IR FEL D. Douglas, S. V, Newport News, VA23606, USA Abstract An upgrade of the Jefferson Lab IR FEL [1] is now un� der construction. It will provide 10 kW output light power in a wavelength range of 2--10 �m. The FEL will be driven by a modest
A scintillating fiber hodoscope has been built for use as a photon beam profiler in the bremsstrahlung tagged photon beam in Hall B of the Thomas Jefferson National Accelerator Facility (Jefferson Lab). The device consists of a linear array of 64 2-2 mm2 scintillating fibers glued to a corresponding set of light ...
The CEBAF Large Acceptance Spectrometer (CLAS) has recently been commissioned in Hall B of the Thomas Jefferson National Accelerator Facility (Jefferson Lab). The six ``Region 2'' drift chambers, built by Old Dominion University with technical support from Jefferson Lab, are located between the ...
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 of the model's implementation allows rapid {open_quotes}what ...
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} ...
The inclusive, inelastic eD scattering cross section has been measured with the CLAS detector in Hall B of the Thomas Jefferson National Accelerator Facility (TJNAF). Combining these data and previously measured world data we have extracted Nachtmann moments of the deuteron structure function F2 in the region 0.4 < Q2 < ...
A proposal to search for exotic mesons in photoproduction has been accepted for running at Thomas Jefferson National Accelerator Facility, using the CEBAF Large Acceptance Spectrometer in Hall B. This program will bolster previously-thin statistics in many photoproduction channels, primarily those with charged particles in the final ...
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 ...
