Precision Electron Beam Polarimetry in Hall C at Jefferson Lab

NASA Astrophysics Data System (ADS)

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.

Pair spectrometer hodoscope for Hall D at Jefferson Lab

DOE PAGES

Barbosa, Fernando J.; Hutton, Charles L.; Sitnikov, Alexandre; ...

2015-09-21

We present the design of the pair spectrometer hodoscope fabricated at Jefferson Lab and installed in the experimental Hall D. The hodoscope consists of thin scintillator tiles; the light from each tile is collected using wave-length shifting fibers and detected using a Hamamatsu silicon photomultiplier. Light collection was measured using relativistic electrons produced in the tagger area of the experimental Hall B.

Pair spectrometer hodoscope for Hall D at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barbosa, Fernando J.; Hutton, Charles L.; Sitnikov, Alexandre

We present the design of the pair spectrometer hodoscope fabricated at Jefferson Lab and installed in the experimental Hall D. The hodoscope consists of thin scintillator tiles; the light from each tile is collected using wave-length shifting fibers and detected using a Hamamatsu silicon photomultiplier. Light collection was measured using relativistic electrons produced in the tagger area of the experimental Hall B.

Jefferson Lab 12 GEV Cebaf Upgrade

NASA Astrophysics Data System (ADS)

Rode, C. H.

2010-04-01

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, sponsored by the Department of Energy (DOE) Office of Nuclear Physics, that will expand its research capabilities substantially by doubling the maximum energy and adding major new experimental apparatus. The project received construction approval in September 2008 and has started the major procurement process. The cryogenic aspects of the 12 GeV CEBAF Upgrade includes: doubling the accelerating voltages of the Linacs by adding ten new high-performance, superconducting radiofrequency (SRF) cryomodules (CMs) to the existing 42 1/4 cryomodules; doubling of the 2 K cryogenics plant; and the addition of eight superconducting magnets.

Progress of ILC High Gradient SRF Cavity R&D at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

R.L. Geng, J. Dai, G.V. Eremeev, A.D. Palczewski

2011-09-01

Latest progress of ILC high gradient SRF cavity R&D at Jefferson Lab will be presented. 9 out of 10 real 9-cell cavities reached an accelerating gradient of more than 38 MV/m at a unloaded quality factor of more than 8 {center_dot} 109. New understandings of quench limitation in 9-cell cavities are obtained through instrumented studies of cavities at cryogenic temperatures. Our data have shown that present limit reached in 9-cell cavities is predominantly due to localized defects, suggesting that the fundamental material limit of niobium is not yet reached in 9-cell cavities and further gradient improvement is still possible. Somemore » examples of quench-causing defects will be given. Possible solutions to pushing toward the fundamental limit will be described.« less

EMC effect for light nuclei: New results from Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aji Daniel

High energy lepton scattering has been the primary tool for mapping out the quark distributions of nucleons and nuclei. Measurements of deep inelastic scattering in nuclei show that the quark distributions in heavy nuclei are not simply the sum of the quark distributions of the constituent proton and neutron, as one might expect for a weakly bound system. This modification of the quark distributions in nuclei is known as the EMC effect. I will discuss the results from Jefferson Lab (JLab) experiment E03-103, a precise measurement of the EMC effect in few-body nuclei with emphasis on the large x region.more » Data from the light nuclei suggests that the nuclear dependence of the high x quark distribution may depend on the nucleon's local environment, rather than being a purely bulk effect. In addition, I will also discuss about a future experiment at the upgraded 12 GeV Jefferson Lab facility which will further investigate the role of the local nuclear environment and the influence of detailed nuclear structure to the modification of quark distributions.« less

Jefferson Lab Experimental Hall C

NASA Astrophysics Data System (ADS)

Carlini, Roger D.

1996-10-01

Jefferson Lab's Hall C went into initial operation in November 1995. The hall has a short orbit spectrometer (SOS) for short-lived particles such as pions and kaons and a high-momentum spectrometer (HMS) usually used for electrons. The SOS can also be used for protons. The HMS can range to 7 GeV/c. Both the SOS and HMS have typical resolutions of (10-3). Experiments for this hall range from measuring the neutron electric form factor, to color transparency, to creating strange nuclei. This paper will present the optical capabilities of the spectrometers, the parameters of the detection systems, and the overall beam line characteristics of the hall as determined from the results from the recent physics experiments along with the upcoming experimental schedule. Additional information is available at URL http://www.cebaf.gov/hallc.html.

An overview of recent nucleon spin structure measurements at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allada, Kalyan

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 lowmore » 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.« less

5 MeV Mott Polarimeter Development at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Price, J. S.; Sinclair, C. K.; Cardman, L. S.

1997-01-01

Low energy (E{sub k}=100 keV) Mott scattering polarimeters are ill- suited to support operations foreseen for the polarized electron injector at Jefferson Lab. One solution is to measure the polarization at 5 MeV where multiple and plural scattering are unimportant and precision beam monitoring is straightforward. The higher injector beam current offsets the lower cross-sections. Recent improvements in the CEBAF injector polarimeter scattering chamber have improved signal to noise.

Superconducting Magnets for the 12 GeV Upgrade at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fair, Ruben J.; Young, Glenn R.

2015-06-01

Jefferson Laboratory is embarked on an energy upgrade to its flagship continuous electron beam accelerator in order to expand the scope of its research capabilities and probe further into the structure of nuclear particles. The 12 GeV upgrade includes the design, manufacture, integration, installation and commissioning of eight different superconducting magnets in three separate experimental halls. The effort involves other national laboratories, universities and industry spanning three countries. This paper will summarize the key characteristics of these magnets, ranging in size from 0.2 to 23 MJ in stored energy, and featuring many different types and configurations. The paper will alsomore » give an overview of the specific technical challenges for each magnet, and a status report on magnet manufacture and expected delivery dates. The 12GeV upgrade at J-Lab represents the largest superconducting magnet fabrication and installation program currently ongoing in the United States and this paper will present the breadth of collaborations supporting it.« less

Addressing Physics Grand Challenges Using the Jefferson Lab FEL

NASA Astrophysics Data System (ADS)

Williams, Gwyn P.

2006-11-01

The Jefferson Lab Free Electron Laser[1] is the first of the so-called 4^th generation light sources to go operational. Capable of delivering extraordinarily bright, tunable light in ultrafast pulses from THz[2] through infrared to UV, the facility extends the experimental reach of accelerator-based light-sources by many orders of magnitude. This allows new opportunities to study many of the ``Grand Challenges'' recently defined by the Office of Science, Basic Energy Sciences Division, most of which are concerned with understandings of equilibrium and non-equilibrium behavior of materials in physics, chemistry and biology using precise pump and probe techniques. Specifically, in condensed matter physics, the JLab FEL permits new studies which go beyond earlier studies of reductionist behavior to those which examine emergent behavior. Thus, the understanding of high Tc superconductivity, colossal magneto-resistance, and observations of the breakdown of the Born-Oppenheimer approximation, are examples of collective behavior which is now treated theoretically via the concept of quasiparticles. In this presentation we will describe the dual pathways of light source development and physics challenges, and then show how they are combined in experiments that allow new insights to be developed to understand material function. We will illustrate this with details of the evolution of accelerator-based light sources, and with examples of work performed to date. References: [1] Neil et al. Phys. Rev.Letts 84, 662 (2000). [2] Carr, Martin, McKinney, Neil, Jordan & Williams, Nature 420, 153 (2002).

Results From the N* Program at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Inna Aznauryan, Volker Burkert, Tsung-Shung Lee, Viktor Mokeev

2011-06-01

We discuss the results on the fundamental degrees of freedom underlying the nucleon excitation spectrum and how they evolve as the resonance transitions are investigated with increasingly better space-time resolution of the electromagnetic probe. Improved photocouplings for a number of resonant states, those for the N(1720)P13 being significantly changed, have been determined and entered into the 2008 edition of the RPP. Strong sensitivity to the N(1900)P13 state, listed now as a 2-star state in the same edition of RPP, has been observed in KΛ and KΣ photoproduction. None of the earlier observations of a Θ+5(1540) was confirmed in a seriesmore » of three Jefferson Lab high statistics dedicated measurements, and stringent upper limits on production cross sections were placed in several channels. For the four lowest excited states, the Δ(1232)P33, N(1440)P11, N(1520)D13, and N(1535)S11, the transition amplitudes have been measured in a wide range in photon virtuality Q2. The amplitudes for the Δ(1232) show the importance of the pion-cloud contribution and do not show any sign of approaching the pQCD regime for Q2 < 7 GeV2. For the Roper resonance, N(1440)P11, the data provide strong evidence for this state as a predominantly radial excitation of the nucleon as a 3-quark ground state. For the N(1535)S11, comparison of the results extracted from π and η photo- and electroproduction data allowed one to specify the branching ratios of this state to the πN and ηN channels; they entered into the 2010 edition of the RPP. Measured for the first time, the longitudinal transition amplitude for the N(1535)S11 became a challenge for quark models and can be indicative of large meson-cloud contributions or alternative representations of this state. The N(1520)D13 clearly shows the rapid changeover from helicity-3/2 dominance at the real photon point to helicity-1/2 dominance at Q2 > 0.5 GeV2 confirming a long-standing prediction of the constituent quark model. The

Short Distance of Nuclei - Mining the Wealth of Existing Jefferson Lab Data - Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weinstein, Lawrence; Kuhn, Sebastian

Over the last fifteen years of operation, the Jefferson Lab CLAS Collaboration has performed many experiments using nuclear targets. Because the CLAS detector has a very large acceptance and because it used a very open (i.e., nonspecific) trigger, there is a vast amount of data on many different reaction channels yet to be analyzed. The goal of the Jefferson Lab Nuclear Data Mining grant was to (1) collect the data from nuclear target experiments using the CLAS detector, (2) collect the associated cuts and corrections used to analyze that data, (3) provide non-expert users with a software environment for easymore » analysis of the data, and (4) to search for interesting reaction signatures in the data. We formed the Jefferson Lab Nuclear Data Mining collaboration under the auspices of this grant. The collaboration successfully carried out all of our goals. Dr. Gavalian, the data mining scientist, created a remarkably user-friendly web-based interface to enable easy analysis of the nuclear-target data by non-experts. Data from many of the CLAS nuclear target experiments has been made available on servers at Old Dominion University. Many of the associated cuts and corrections have been incorporated into the data mining software. The data mining collaboration was extraordinarily successful in finding interesting reaction signatures in the data. Our paper Momentum sharing in imbalanced Fermi systems was published in Science. Several analyses of CLAS data are continuing and will result in papers after the end of the grant period. We have held several analysis workshops and have given many invited talks at international conferences and workshops related to the data mining initiative. Our initiative to maximize the impact of data collected with CLAS in the 6-GeV era was very successful. During the hiatus between the end of 6-GeV experiments and the beginning of 12-GeV experiments, our collaboration and the physics community at large benefited tremendously from the

Searching for dark photon with positrons at Jefferson lab

NASA Astrophysics Data System (ADS)

Marsicano, Luca

2018-05-01

The interest in the Dark Photon (A' or U) has recently grown, since it could act as a light mediator to a new sector of Dark Matter particles. In this paradigm, the electron-positron annihilation can rarely produce a γA' pair. Various experiments (e.g. PADME@LNF [1], VEPP-3 [2]) have been proposed to detect this process using positron beams impinging on fixed targets. In such experiments, the energy of the photon from the e+e-→ γA' process is measured with an electromagnetic calorimeter and the missing mass is computed (the A' interacts weakly with Standard Model matter so it can't be detected). However, the A' mass range that can be explored with this technique is limited by the accessible energy in the center of mass frame, which goes as the square root of the beam energy. The realization of a 11 GeV positron beam at Jefferson Lab would allow to search for A' masses up to ˜ 100 MeV, reaching unexplored regions of the A' parameter space. A preliminary study on the feasibility of a PADME-like experiment at Jefferson Lab has been carried out, assuming a 11 GeV positron beam with a ˜ 100 nA current. The achievable sensitivity was estimated, studying the main sources of background (positron bremsstrahlung, annihilation into 2 gammas) using CALCHEP [3] and GEANT4 [4] simulations.

Di-hadron production at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anefalos Pereira, Sergio; et. al.,

Semi-inclusive deep inelastic scattering (SIDIS) has been used extensively in recent years as an important testing ground for QCD. Studies so far have concentrated on better determination of parton distribution functions, distinguishing between the quark and antiquark contributions, and understanding the fragmentation of quarks into hadrons. Hadron pair (di-hadron) SIDIS provides information on the nucleon structure and hadronization dynamics that complement single hadron SIDIS. Di-hadrons allow the study of low- and high-twist distribution functions and Dihadron Fragmentation Functions (DiFF). Together with the twist-2 PDFs ( f1, g1, h1), the Higher Twist (HT) e and hL functions are very interesting becausemore » they offer insights into the physics of the largely unexplored quark-gluon correlations, which provide access into the dynamics inside hadrons. The CLAS spectrometer, installed in Hall-B at Jefferson Lab, has collected data using the CEBAF 6 GeV longitudinally polarized electron beam on longitudinally polarized solid NH3 targets. Preliminary results on di-hadron beam-, target- and double-spin asymmetries will be presented.« less

Production of Charmonium at Threshold in Hall A and C at Jefferson Lab

DOE PAGES

Hafidi, K.; Joosten, S.; Meziani, Z. -E.; ...

2017-05-27

Here, we describe in this paper two approved experiments in Hall A and Hall C at Jefferson Lab that will investigate the pure gluonic component of the strong interaction of Quantum ChromoDynamics by measuring the elastic J/ψ electro and photo-production cross section in the threshold region as well as explore the nature of the recently discovered LHCb charmed pentaquarks.

The Search for Missing Baryons with Linearly Polarized Photons at Jefferson Lab

NASA Astrophysics Data System (ADS)

Cole, Philip

2006-05-01

The set of experiments forming the g8 run took place in Hall B of Jefferson Lab during the summers of 2001 and 2005 These experiments made use of a beam of linearly-polarized photons produced through coherent bremsstrahlung and represent the first time such a probe has been employed at Jefferson Lab. The scientific purpose of g8 is to improve the understanding of the underlying symmetry of the quark degrees of freedom in the nucleon, the nature of the parity exchange between the incident photon and the target nucleon, and the mechanism of associated strangeness production in electromagnetic reactions. With the high-quality beam of the tagged and collimated linearly-polarized photons and the nearly complete angular coverage of the Hall-B spectrometer, we seek to extract the differential cross sections and attendant polarization observables for the photoproduction of vector mesons and kaons at photon energies ranging between 1.3 and 2.2 GeV. We achieved polarizations exceeding 90% and collected over six billion events, which, after our data cuts and analysis, should give us well over 100 times the world's data set. I shall report on the experimental details of establishing the Coherent Bremsstrahlung Facility and present some preliminary results from our first run.

A SYNCHRONIZED FIR/VUV LIGHT SOURCE AT JEFFERSON LAB

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stephen Benson, David Douglas, George Neil, Michelle D. Shinn, Gwyn Williams

We describe a dual free-electron laser (FEL) configuration on the UV Demo FEL at Jefferson Lab that allows simultaneous lasing at FIR/THz and UV wavelengths. The FIR/THz source would be an FEL oscillator with a short wiggler providing nearly diffraction-limited pulses with pulse energy exceeding 50 microJoules. The FIR source would use the exhaust beam from a UVFEL. The coherent harmonics in the VUV from the UVFEL are out-coupled through a hole. The FIR source uses a shorter resonator with either hole or edge coupling to provide very high power FIR pulses. Simulations indicate excel-lent spectral brightness in the FIRmore » region with over 100 W/cm-1 output.« less

The CLAS12 torus detector magnet at Jefferson Laboratory

DOE PAGES

Luongo, Cesar; Wiseman, Mark A.; Kashy, David H.; ...

2015-12-17

The CLAS12 Torus is a toroidal superconducting magnet, part of the detector for the 12GeV accelerator upgrade at Jefferson Lab. The coils were wound/fabricated by Fermi Lab, with Jlab responsible for all other parts of the project scope, including design, integration, cryostating the individual coils, installation, cryogenics, I&C, etc. The study 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.

Spectroscopic Study of L Hypernuclei with Electron Beams at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakamura, Satoshi; Gogami, Toshiyuki; Tang, Liguang

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.

CLAS+FROST: new generation of photoproduction experiments at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eugene Pasyuk

2009-12-01

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 ofmore » the experiment and its current status is presented.« less

Overview of torus magnet coil production at Fermilab for the Jefferson Lab 12-GeV Hall B upgrade

DOE PAGES

Krave, S.; Velev, G.; Makarov, A.; ...

2016-02-29

Fermi National Accelerator Laboratory (Fermilab) fabricated the torus magnet coils for the 12-GeV Hall B upgrade at Jefferson Lab (JLab). The production consisted of six large superconducting coils for the magnet and two spare coils. The toroidal field coils are approximately 2 m × 4 m × 5 cm thick. Each of these coils consists of two layers, each of which has 117 turns of copper-stabilized superconducting cable, which will be conduction cooled by supercritical helium. Due to the size of the coils and their unique geometry, Fermilab designed and fabricated specialized tooling and, together with JLab, developed unique manufacturingmore » techniques for each stage of the coil construction. Furthermore, this paper describes the tooling and manufacturing techniques required to produce the six production coils and the two spare coils needed by the project.« less

Data consistency checks for Jefferson Lab Experiment E00-002

NASA Astrophysics Data System (ADS)

Telfeyan, John; Niculescu, Gabriel; Niculescu, Ioana

2006-10-01

Jefferson Lab experiment E00-002 aims to measure inclusive electron-proton and electron-deuteron scattering cross section at low Q squared and moderately low Bjorken x. Data in this kinematic region will further our understanding of the transition between the perturbative and non-perturbative regimes of Quantum Chromodynamics (QCD). As part of the data analysis effort underway at James Madison University (JMU) a comprehensive set of checks and tests was implemented. These tests ensure the quality and consistency of the experimental data, as well as providing, where appropriate, correction factors between the experimental apparatus as used and its idealized computer-simulated representation. This contribution will outline this testing procedure as implemented in the JMU analysis, highlighting the most important features/results.

Basic instrumentation for Hall A at Jefferson Lab

NASA Astrophysics Data System (ADS)

Alcorn, J.; Anderson, B. D.; Aniol, K. A.; Annand, J. R. M.; Auerbach, L.; Arrington, J.; Averett, T.; Baker, F. T.; Baylac, M.; Beise, E. J.; Berthot, J.; Bertin, P. Y.; Bertozzi, W.; Bimbot, L.; Black, T.; Boeglin, W. U.; Boykin, D. V.; Brash, E. J.; Breton, V.; Breuer, H.; Brindza, P.; Brown, D.; Burtin, E.; Calarco, J. R.; Cardman, L. S.; Carr, R.; Cates, G. D.; Cavata, C.; Chai, Z.; Chang, C. C.; Chant, N. S.; Chen, J.-P.; Choi, S.; Chudakov, E.; Churchwell, S.; Coman, M.; Cisbani, E.; Colilli, S.; Colombel, N.; Crateri, R.; Dale, D. S.; Degrande, N.; de Jager, C. W.; De Leo, R.; Deur, A.; Dezern, G.; Diederich, B.; Dieterich, S.; di Salvo, R.; Djawotho, P.; Domingo, J.; Ducret, J.-E.; Dutta, D.; Egiyan, K.; Epstein, M. B.; Escoffier, S.; Esp, S.; Ewell, L. A.; Finn, J. M.; Fissum, K. G.; Folts, E.; Fonvieille, H.; Frois, B.; Frullani, S.; Gao, H.; Gao, J.; Garibaldi, F.; Gasparian, A.; Gavalya, A.; Gayou, O.; Gilad, S.; Gilman, R.; Giuliani, F.; Glamazdin, A.; Glashausser, C.; Gomez, J.; Gorbenko, V.; Gorringe, T.; Gricia, M.; Griffioen, K.; Hamilton, D.; Hansen, J.-O.; Hersman, F. W.; Higinbotham, D. W.; Holmes, R.; Holmgren, H.; Holtrop, M.; d'Hose, N.; Hovhannisyan, E.; Howell, C.; Huber, G. M.; Hughes, E.; Hyde-Wright, C. E.; Ibrahim, H.; Incerti, S.; Iodice, M.; Iommi, R.; Ireland, D.; Jaminion, S.; Jardillier, J.; Jensen, S.; Jiang, X.; Jones, C. E.; Jones, M. K.; Joo, K.; Jutier, C.; Kahl, W.; Kato, S.; Katramatou, A. T.; Kelly, J. J.; Kerhoas, S.; Ketikyan, A.; Khandaker, M.; Khayat, M.; Kino, K.; Kominis, I.; Korsch, W.; Kox, S.; Kramer, K.; Kumar, K. S.; Kumbartzki, G.; Kuss, M.; Lagamba, L.; Laveissière, G.; Leone, A.; LeRose, J. J.; Marie, F.; Levchuk, L.; Leuschner, M.; Lhuillier, D.; Liang, M.; Livingston, K.; Lindgren, R. A.; Liyanage, N.; Lolos, G. J.; Lourie, R. W.; Lucentini, M.; Madey, R.; Maeda, K.; Malov, S.; Manley, D. M.; Margaziotis, D. J.; Markowitz, P.; Marroncle, J.; Martine, J.; Mayilyan, S.; McCarthy, J. S.; McCormick, K.; Mclntyre, J.; McKeown, R. D.; Meekins, D.; van der Meer, R. L. J.; Meziani, Z.-E.; Michaels, R.; Milbrath, B.; Miller, J. A.; Miller, W.; Mitchell, J.; Mougey, J.; Nanda, S.; Nathan, A.; Neyret, D.; Offermann, E. A. J. M.; Papandreou, Z.; Perdrisat, C. F.; Perrino, R.; Petratos, G. G.; Petrosyan, A.; Pierangeli, L.; Platchkov, S.; Pomatsalyuk, R.; Pripstein, D.; Prout, D. L.; Punjabi, V. A.; Pussieux, T.; Quéméner, G.; Ransomez, R. D.; Ravel, O.; Reitz, B.; Roblin, Y.; Roche, R.; Roedelbronn, M.; Rondon-Aramayo, O. A.; Roos, P. G.; Rosner, G.; Rowntree, D.; Rutledge, G. A.; Rutt, P. M.; Rvachev, M.; Sabatavenere, F.; Saha, A.; Saito, T.; Santavenere, F.; Sarty, A. J.; Schneider, W. J.; Segal, J. P.; Serdarevic-Offermann, A.; Shahinyan, A.; Slifer, K.; Smith, T. P.; Soldi, A.; Sorokin, P.; Souder, P.; Spiegel, S. L.; Stevens, M. A.; Strauch, S.; Suleiman, R.; Templon, J. A.; Terasawa, T.; Todor, L.; Tsubota, H.; Ueno, H.; Ulmer, P. E.; Urciuoli, G. M.; Van Hoorebeke, L.; Van de Vyver, R.; van Verst, S.; Vernin, P.; Vlahovic, B.; Voskanyan, H.; Voutier, E.; Walter, R.; Watson, J. W.; Watts, D. P.; Weinstein, L. B.; Wijesooriya, K.; Wojtsekhowski, B.; Xiang, H.; Xiong, F.; Xu, W.; Zainea, D. G.; Zeps, V.; Zhao, J.; Zheng, X.; Zhou, Z.-L.; Zhu, L.; Zolnierczuk, P. A.

2004-04-01

The instrumentation in Hall A at the Thomas Jefferson National Accelerator Facility was designed to study electro- and photo-induced reactions at very high luminosity and good momentum and angular resolution for at least one of the reaction products. The central components of Hall A are two identical high resolution spectrometers, which allow the vertical drift chambers in the focal plane to provide a momentum resolution of better than 2×10 -4. A variety of Cherenkov counters, scintillators and lead-glass calorimeters provide excellent particle identification. The facility has been operated successfully at a luminosity well in excess of 10 38 cm-2 s-1. The research program is aimed at a variety of subjects, including nucleon structure functions, nucleon form factors and properties of the nuclear medium.

Jefferson Lab Mass Storage and File Replication Services

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ian Bird; Ying Chen; Bryan Hess

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 is 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 andmore » being used to archive 1 TB per day from the experiments, and currently moves over 2 TB per day total. This paper will describe the architecture of JASMine; discuss the rationale for building the system, and present a transparent 3rd party file replication service to move data to collaborating institutes using JASMine, XM L, and servlet technology interfacing to grid-based file transfer mechanisms.« less

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

DOE PAGES

Friend, M.; Parno, D.; Benmokhtar, F.; ...

2012-06-01

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 system (DAQ) 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 2SiO 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.

Physics Opportunities with the 12 GeV Upgrade at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dudek, Jozef; Essig, Rouven; Kumar, Krishna

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 willmore » 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.« less

Computational Accelerator Physics. Proceedings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bisognano, J.J.; Mondelli, A.A.

1997-04-01

The sixty two papers appearing in this volume were presented at CAP96, the Computational Accelerator Physics Conference held in Williamsburg, Virginia from September 24{minus}27,1996. Science Applications International Corporation (SAIC) and the Thomas Jefferson National Accelerator Facility (Jefferson lab) jointly hosted CAP96, with financial support from the U.S. department of Energy`s Office of Energy Research and the Office of Naval reasearch. Topics ranged from descriptions of specific codes to advanced computing techniques and numerical methods. Update talks were presented on nearly all of the accelerator community`s major electromagnetic and particle tracking codes. Among all papers, thirty of them are abstracted formore » the Energy Science and Technology database.(AIP)« less

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

DOE PAGES

Rakhman, A.; Hafez, Mohamed A.; Nanda, Sirish K.; ...

2016-03-31

Here, 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 enhancementmore » 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 1.0 GeV and 50 μA.« less

Precision Compton polarimetry for the QWeak experiment at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wouter Deconinck

2011-10-01

The Q Weak experiment, scheduled to run in 2010-2012 in Hall C at Jefferson Lab, will measure the parity-violating asymmetry in elastic electron-proton scattering at 1.1 GeV to determine the weak charge of the proton, Q{sub Weak}{sup p} = 1 - 4 sin{sup 2} {theta}{sub W}. The dominant experimental systematic uncertainty will be the knowledge of the electron beam polarization. With a new Compton polarimeter we aim to measure the beam polarization with a statistical precision of 1% in one hour and a systematic uncertainty of 1%. A low-gain Fabry-Perot cavity laser system provides the circularly polarized photons. The scatteredmore » electrons are detected in radiation-hard diamond strip detectors, and form the basis for a coincidence trigger using distributed logic boards. The photon detector uses a fast, undoped CsI crystal with simultaneous sampling and integrating read-out. Coincident events are used to cross-calibrate the photon and electron detectors.« less

Low momentum recoil detectors in CLAS12 at Jefferson Lab

NASA Astrophysics Data System (ADS)

Charles, Gabriel; CLAS Collaboration Collaboration

2017-01-01

Part of the experimental program in Hall B of the Jefferson Lab is dedicated to studying nucleon structure using DIS on nuclei and detecting low-momentum recoil particles in coincidence with the scattered electron. For this purpose, specially designed central detectors are required in place of the inner tracker of CLAS12 to detect particles with momenta below 100 MeV/c. We will present the status of the BONuS12 RTPC detector that will take data within the next 2 years. We will detail the main improvements made from the previous BONuS RTPC. In a second part, we will discuss another recoil experiment, called ALERT, that has been proposed to run in Hall B. The constraints being different, the recoil detector is based on a drift chamber and an array of scintillators. We will present the main differences between the two detectors and summarize the R&D performed to develop the ALERT detector.

High-gradient SRF R&D for ILC at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Geng, Rongli; Crawford, Anthony; Ciovati, Gianluigi

2008-10-01

Jefferson Lab plays an active role in high-gradient SRF R&D in the frame work of the internationally coordinated ILC S0 program. The S0 aim is to push the yield at 35 MV/m in 9-cell cavities. So far, twelve cavities have been electropolishing (EP) processed and RF tested by using the state-of-the-art recipes at JLab, in close collaboration with FNAL and KEK. Seven of them reached a best gradient of over 31.5 MV/m. Understanding gradient limiting mechanisms in real 9-cell cavities is an important component of our studies. Thermometry and high-resolution optical inspection are used to locate and understand the sourcemore » of gradient limits. Experimenting with selective cavities is still a necessary method for process optimization. One example is the first demonstration of 35 MV/m without detectable Bremsstrahlung X-ray after a light EP is applied to a previously heavy BCP etched 7-cell cavity. Some new understanding has been gained with regard to quench behaviors, field emission behaviors as« less

A new THz/Far-IR beamline at the Jefferson Lab ERL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Neil, George; Williams, Gwyn

2003-08-01

Multiparticle coherent synchrotron emitted by sub-picosecond bunches of electrons in an energy recovering linac, (ERL), at 75 MHz, yield average powers of ~ 100 watts, even for beam currents of 10 mA.This is 10,000 times higher than typical table-top systems.We describe a new ERL facility under construction at Jefferson Lab, and a new THz extraction system and beamline.We also present theoretical calculations.Potential applications of this exciting new source include driving new non-linear phenomena, performing pump-probe studies of dynamical properties of novel materials, and studying molecular vibrations and rotations, low frequency protein motions, phonons, superconductor bandgaps, electronic scattering, collective electronic excitationsmore » (e.g., charge density waves), and spintronics.This work was supported by the US Department of Energy, the Office of Naval Research and the Commonwealth of Virginia.G.L. Carr, M.C. Martin, W.R. McKinney, K. Jordan, G.R. Neil and G.P. Wi« less

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

NASA Astrophysics Data System (ADS)

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.

Measurement of parity-violating asymmetry in deep inelastic scattering at Jefferson Lab

NASA Astrophysics Data System (ADS)

Zheng, Xiaochao

2015-04-01

Symmetry permeates nature and is fundamental to all laws of physics. One example is mirror symmetry, also called ``parity symmetry''. It implies that flipping left and right does not change the laws of physics. Laws for electromagnetism, gravity and the subatomic strong force respect parity symmetry, but the subatomic weak force does not. Historically, parity violation in electron scattering played a key role in establishing, and now testing, the Standard Model of particle physics. One particular set of the quantities accessible through measurements of parity-violating electron scattering are the vector-electron axial-vector-quark weak couplings, called C2 q's, measured directly only once in the past 40 years. We report here on a new measurement of the parity-violating asymmetry in electron-quark scattering, that has yielded a specific combination 2C2 u -C2 d five times more precise than the earlier result. (Here u and d stand respectively for the up and the down quarks.) These results are the first evidence, at more than the 95% confidence level, that the C2 q's are non-zero as predicted by the electroweak theory. They lead to constraints on new interactions beyond the Standard Model, particularly on those whose laws change when the quark chirality is flipped between left and right. In today's particle physics research that is focused on colliders such as the LHC, our results provide specific chirality information on electroweak theory that is difficult to obtain at high energies. In addition to deep inelastic scattering, we will report on measurement of the asymmetry in the nucleon resonance region. These data exhibit for the first time that the quark-hadron duality may work for electroweak observables at the (10--15)% level throughout the whole resonance region. At the end I will give a brief outlook on the future PVDIS program using the Jefferson Lab 12 GeV beam, which will not only provide more precise measurement of C2 q, but also for sin2 θW and for

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Montgomery, Rachel; Annand, John; Dutta, Dipangkar

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 themore » first TDIS results in the valence regime, for both proton and neutron targets. We present here an overview of the experiment.« less

Scaling behavior in exclusive meson photoproduction from Jefferson Lab at large momentum transfers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dey, Biplab

2014-07-01

With the availability of new high-statistics and wide-angle measurements for several exclusive non-πN meson photoproduction channels from Jefferson Lab, we examine the fundamental scaling law of 90° scattering in QCD that was originally derived in the high-energy perturbative limit. The data show scaling to be prominently visible even in the medium-energy domain of 2.5 GeV ≲√s≲2.84 GeV, where √s is the center-of-mass energy. While constituent quark exchange suffices for pseudoscalar mesons, additional gluon exchanges from higher Fock states of the hadronic wave functions appear be needed for vector-meson production. Finally, the case of the Φ(1020), where two-gluon exchanges are knownmore » to dominate, is especially illuminating.« less

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benson, Stephen V.; Derbenev, Yaroslav S.; Douglas, David R.

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 usesmore » 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.« less

Comparison of two data acquisition and processing systems of Moller polarimeter in Hall A of Jefferson Lab

DOE PAGES

Vereshchaka, Vadym V.; Glamazdin, Oleksandr V.; Pomatsalyuk, Roman I.

2014-07-01

Two data acquisition and processing systems are used simultaneously to measure electron beam polarization by Moller polarimeter in Hall A of Jefferson Lab (Newport News, VA, USA). The old system (since 1997) is fully functional, but is not repairable in case of malfunction (system modules arenot manufactured anymore). The new system (since 2010) based on flash-ADC is more accurate, but currently requires more detailed adjustment and further improvement. Description and specifications of two data acquisition and processing systems have been given. The results of polarization measurements during experiments conducted in Hall A from 2010 to 2012 are compared.

Dynamically polarized target for the g {2/ p } and G {/E p } experiments at Jefferson Lab

NASA Astrophysics Data System (ADS)

Pierce, J.; Maxwell, J.; Keith, C.

2014-01-01

Recently, two experiments were concluded in Hall A at Jefferson Lab which utilized a newly assembled, solid, polarized hydrogen target. The primary components of the target are a new, high cooling power 4He evaporation refrigerator, and a re-purposed, superconducting split-coil magnet. It has been used to polarize protons in irradiated NH3 at a temperature of 1 K and at fields of 2.5 and 5.0 tesla. Maximum polarizations of 55% and 95% were obtained at those fields, respectively. To satisfy the requirements of both experiments, the magnet had to be routinely rotated between angles of 0°, 6°, and 90° with respect to the incident electron beam.

Performance and Results for Quartz Detector for the SuperHMS Spectrometer at Hall C Jefferson Lab

NASA Astrophysics Data System (ADS)

Griego, Benjamin F., Jr.

A quartz detector has been constructed to be part of the trigger system for the Super High Momentum Spectrometer (SHMS). The SHMS will play a pivotal role in carrying out the 12 -- GeV physics program at Hal -- C Jefferson Lab. The quartz hodoscope consists of twenty one fused silica bars. Each bar is 125 cm long, 5.5 cm wide, 2.5 cm thick, and is viewed by a UV -- sensitive PMT on each end. The quartz hodoscope's task is to provide a clean detection of charged particles, a high level of background suppression, and an accurate tracking efficiency determination. Initial test results of the quartz detectors which include light yield and position resolution will be presented.

Polarized positrons in Jefferson lab electron ion collider (JLEIC)

NASA Astrophysics Data System (ADS)

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.

Studies with cathode drift chambers for the GlueX experiment at Jefferson Lab

DOE PAGES

Pentchev, L.; Barbosa, F.; Berdnikov, V.; ...

2017-04-22

A drift chamber system consisting of 24 1 m-diameter chambers with both cathode and wire readout (total of 12,672 channels) is operational in Hall D at Jefferson Lab (Virginia). Two cathode strip planes and one wire plane in each chamber register the same avalanche allowing the study of avalanche development, charge induction process, and strip resolution. We demonstrate a method for reconstructing the two-dimensional distribution of the avalanche “center-of-gravity” position around the wire from an 55Fe source with resolutions down to 30 μm. We estimate the azimuthal extent of the avalanche around the wire as a function of the totalmore » charge for an Ar/CO 2 gas mixture. By means of cluster counting using a modified 3 cm-gap chamber, we observe significant space charge effects within the same track, resulting in an extent of the avalanche along the wire.« less

Radiation and ionization energy loss simulation for the GDH sum rule experiment in Hall-A at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Xin -Hu; Ye, Yun -Xiu; Chen, Jian -Ping

2015-07-17

The radiation and ionization energy loss are presented for single arm Monte Carlo simulation for the GDH sum rule experiment in Hall-A at Jefferson Lab. Radiation and ionization energy loss are discussed formore » $$^{12}C$$ elastic scattering simulation. The relative momentum ratio $$\\frac{\\Delta p}{p}$$ and $$^{12}C$$ elastic cross section are compared without and with radiation energy loss and a reasonable shape is obtained by the simulation. The total energy loss distribution is obtained, showing a Landau shape for $$^{12}C$$ elastic scattering. This simulation work will give good support for radiation correction analysis of the GDH sum rule experiment.« less

Performance Testing of Jefferson Lab 12 GeV Helium Screw Compressors

DOE PAGES

Knudsen, P.; Ganni, V.; Dixon, K.; ...

2015-08-10

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 maymore » 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.« less

Performance Testing of Jefferson Lab 12 GeV Helium Screw Compressors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knudsen, P.; Ganni, V.; Dixon, K.

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 maymore » 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.« less

An Investigation into the Electromagnetic Interactions between a Superconducting Torus and Solenoid for the Jefferson Lab 12 GeV Upgrade

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rajput-Ghoshal, Renuka; Ghoshal, Probir K.; Fair, Ruben J.

2015-06-01

The Jefferson Lab 12 GeV Upgrade in Hall B will need CLAS12 detector that requires two superconducting magnets. One is a magnet system consisting of six superconducting trapezoidal racetrack-type coils assembled in a Toroidal configuration (Torus) and the second is an actively shielded solenoidal magnet (Solenoid). Both the torus and solenoid are located in close proximity to one another and are surrounded by sensitive detectors. This paper investigates the electromagnetic interactions between the two systems during normal operation as well as during various fault scenarios as part of a Risk Assessment and Mitigation (RAM).

HDice, Highly-Polarized Low-Background Frozen-Spin HD Targets for CLAS experiments at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wei, Xiangdong; Bass, Christopher; D'Angelo, Annalisa

2012-12-01

Large, portable frozen-spin HD (Deuterium-Hydride) targets have been developed for studying nucleon spin properties with low backgrounds. Protons and Deuterons in HD are polarized at low temperatures (~10mK) inside a vertical dilution refrigerator (Oxford Kelvinox-1000) containing a high magnetic field (up to 17T). The targets reach a frozen-spin state within a few months, after which they can be cold transferred to an In-Beam Cryostat (IBC). The IBC, a thin-walled dilution refrigerator operating either horizontally or vertically, is use with quasi-4{pi} detector systems in open geometries with minimal energy loss for exiting reaction products in nucleon structure experiments. The first applicationmore » of this advanced target system has been used for Spin Sum Rule experiments at the LEGS facility in Brookhaven National Laboratory. An improved target production and handling system has been developed at Jefferson Lab for experiments with the CEBAF Large Acceptance Spectrometer, CLAS.« less

Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Zhihong; Sato, Nobuo; Allada, Kalyan

© 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 themore » 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.« less

Gas Ring-Imagining Cherenkov (GRINCH) Detector for the Super BigBite Spectrometer at Jefferson Lab

NASA Astrophysics Data System (ADS)

Averett, Todd; Wojtsekhowski, Bogdan; Amidouch, Abdellah; Danagoulian, Samuel; Niculescu, Gabriel; Niculescu, Ioana; Jefferson Lab SBS Collaboration Collaboration

2017-01-01

A new gas Cherenkov detector is under construction for the upcoming SuperBigBite spectrometer research program in Hall A at Jefferson Lab. The existing BigBite spectrometer is being upgraded to handle expected increases in event rate and background rate due to the increased luminosity required for the experimental program. The detector will primarily be used to separate good electron events from significant pion and electromagnetic contamination. In contrast to typical gas Cherenkov detectors that use large-diameter photomultiplier tubes and charge integrating ADCs, this detector uses an array of 510 small-diameter tubes that are more than 25x less sensitive to background. Cherenkov radiation clusters will be identified in this array using fast TDCs and a narrow timing window relative to typical ADC gates. In addition, a new FPGA-based DAQ system is being tested to provide a PID trigger using real-time cluster finding. Details of the detector and current status of the project will be presented.

Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ye, Zhihong; Sato, Nobuo; Allada, Kalyan

2017-01-27

Here, 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 transversity quark 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. Especially, we develop a model-independent method based on the hessian matrix analysis that allows to estimate the uncertainties of the transversity quarkmore » distributions and their tensor charge contributions extracted from the pseudo-data for the SoLID. Both u and d-quark transversity distributions are shown to be very well constrained in the kinematical region of the future experiments with the proton and the effective neutron targets.« less

Unveiling the nucleon tensor charge at Jefferson Lab: A study of the SoLID case

NASA Astrophysics Data System (ADS)

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

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

NASA Astrophysics Data System (ADS)

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.

Simulations of a FIR Oscillator with Large Slippage parameter at Jefferson Lab for FIR/UV pump-probe experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benson, Stephen V.; Campbell, L. T.; McNeil, B.W.T.

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 systemmore » both with a small energy spread (UV laser off) and with large energy spread (UV laser on).« less

A double-arm Møller Polarimeter for Jefferson Lab's Hall B

NASA Astrophysics Data System (ADS)

Grún, E.; Krúger, H.; Dermott, S.; Fechtig, H.; Graps, A. L.; Zook, H. A.; Gustafson, B. A.; Hamilton, D. P.; Hanner, M. S.; Heck, A.; Horányi, M.; Kissel, J.; Lindbad, B. A.; Linkert, D.; Linkert, G.; Mann, I.; Mcdonnell, J. A. M.; Morfill, G. E.; Polanskey, C.; Schwehm, G.; Srama, R.

1998-10-01

We have constructed and commissioned a double-arm Møller polarimeter for the Hall B beamline at the Thomas Jefferson National Accelerator Facility. The polarimeter measures the longitudinal polarization of the 0.8-4.0 GeV electron beam as it enters the experimental hall. The primary components of the apparatus are a target chamber, a pair of quadrupole magnets, and a pair of lead/scintillating-fiber detectors. The target chamber contains two 20 μm-thick permendur foils tilted at ± 20^o with respect to the beam axis. A target polarization of approximately 8% is produced along the beam direction by a 90 G (nominal) magnetic field generated by a pair of Helmholtz coils. The scattered Møller-electron pairs are directed toward the detectors by the quadrupoles. The quadrupoles are are individually tuned--depending on the beam energy--to center the peak of the Møller asymmetry (θ_c.m.=90^o) onto the fixed detectors. The real-to-accidental coincident-detection rate is better than 200:1. The beam polarization can be measured to a 3% relative statistical precision in less than 30 minutes with a relative systematic uncertainty of less than 5%.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kageya, Tsuneo; Ho, Dao; Peng, Peng

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 g14more » asymmetries.« less

Study of Double Spin Asymmetries in Inclusive ep Scattering at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kang, Hoyoung

2014-08-01

The spin structure of the proton has been investigated in the high Bjorken x and low momentum transfer Q 2 region. We used Jefferson Lab's polarized electron beam, a polarized target, and a spectrometer to get both the parallel and perpendicular spin asymmetries Apar and Aperp. These asymmetries produced the physics asymmetries A_1 and A_2 and spin structure functions g_1 and g_2. We found Q 2 dependences of the asymmetries at resonance region and higher-twist effects. Our result increases the available data on the proton spin structure, especially at resonance region with low Q 2. Moreover, A_2 and g_2 datamore » show clear Q 2 evolution, comparing with RSS and SANE-BETA. Negative resonance in A_2 data needs to be examined by theory. It can be an indication of very negative transverse-longitudinal interference contribution at W ~ 1.3 GeV. Higher twist effect appears at the low Q 2 of 1.9 GeV 2, although it is less significant than lower Q 2 data of RSS. Twist03 matrix element d_2 was calculated using our asymmetry fits evaluation at Q 2 – 1.9 GeV 2. D-bar_2 = -0.0087±0.0014 was obtained by integrating 0.47 ≤ x ≤ 0.87.« less

Electron Beam Focusing in the Linear Accelerator (linac)

NASA Astrophysics Data System (ADS)

Jauregui, Luis

2015-10-01

To produce consistent data with an electron accelerator, it is critical to have a well-focused beam. To keep the beam focused, quadrupoles (quads) are employed. Quads are magnets, which focus the beam in one direction (x or y) and defocus in the other. When two or more quads are used in series, a net focusing effect is achieved in both vertical and horizontal directions. At start up there is a 5% calibration error in the linac at Thomas Jefferson National Accelerator Facility. This means that the momentum of particles passing through the quads isn't always what is expected, which affects the focusing of the beam. The objective is to find exactly how sensitive the focusing in the linac is to this 5% error. A linac was simulated, which contained 290 RF Cavities with random electric fields (to simulate the 5% calibration error), and a total momentum kick of 1090 MeV. National Science Foundation, Department of Energy, Jefferson Lab, Old Dominion University.

Teaching Jefferson

ERIC Educational Resources Information Center

Smith, Mark A.

2009-01-01

Thomas Jefferson has long fascinated Americans. Even though Jefferson biographer Merrill Peterson once termed Jefferson "impenetrable," a host of recent scholars have tried to penetrate the "inner Jefferson" in an attempt to make him "more vital to people." Trying to understand Jefferson, one could argue, is akin to trying to understand America,…

Dynamically polarized target for the g p 2 and G p E experiments at Jefferson Lab

DOE PAGES

Pierce, J.; Maxwell, J.; Badman, T.; ...

2013-12-16

We describe a dynamically polarized target that has been utilized for two electron scattering experiments in Hall A at Jefferson Lab. The primary components of the target are a new, high cooling power 4 He evaporation refrigerator, and a re-purposed, superconducting split-coil magnet. It has been used to polarize protons in irradiated NH 3 at a temperature of 1 K and at fields of 2.5 and 5.0 Tesla. The performance of the target material in the electron beam under these conditions will be discussed. The maximum polarizations of 28% and 95% were obtained at those fields, respectively. To satisfy themore » requirements of both experiments, the magnet had to be routinely rotated between angles of 0, 6, and 90 degrees with respect to the incident electron beam. This was accomplished using a new rotating vacuum seal which permits rotations to be performed in only a few minutes.« less

APEX: A Prime EXperiment at Jefferson Lab - Test Run Results and Full Run Plans; Update

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beacham, James

2015-06-01

APEX is an experiment at Thomas Jefferson National Accelerator Facility (JLab) in Virginia, USA, that searches for a new gauge boson (A') with sub-GeV mass and coupling to ordinary matter of g' ~ (10 -6 - 10⁻²)e. Electrons impinge upon a fixed target of high-Z material. An A' is produced via a process analogous to photon bremsstrahlung, decaying to an e⁺+e⁻ pair. A test run was held in July of 2010, covering m A' = 175 to 250 MeV and couplings g'/e > 10⁻³. A full run is approved and will cover m A' ~ 65 to 525 MeV andmore » g'/e > 2.3 x 10⁻⁴, and is expected to occur sometime in 2016 or 2017.« less

Beam position reconstruction for the g2p experiment in Hall A at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Pengjia; Allada, Kalyan; Allison, Trent

2015-11-03

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. We found that before and during the experiment, these new devices were tested and debugged, and their performance was also evaluated. In order to achieve themore » 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. Finally, the calculated beam position will be used in the data analysis to accurately determine the kinematics for each event.« less

Studies Of Coherent Synchrotron Radiation And Longitudinal Space Charge In The Jefferson Lab FEL Driver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tennant, Christopher D.; Douglas, David R.; Li, Rui

2014-12-01

The Jefferson Laboratory IR FEL Driver provides an ideal test bed for studying a variety of beam dynamical effects. Recent studies focused on characterizing the impact of coherent synchrotron radiation (CSR) with the goal of benchmarking measurements with simulation. Following measurements to characterize the beam, we quantitatively characterized energy extraction via CSR by measuring beam position at a dispersed location as a function of bunch compression. In addition to operating with the beam on the rising part of the linac RF waveform, measurements were also made while accelerating on the falling part. For each, the full compression point was movedmore » along the backleg of the machine and the response of the beam (distribution, extracted energy) measured. Initial results of start-to-end simulations using a 1D CSR algorithm show remarkably good agreement with measurements. A subsequent experiment established lasing with the beam accelerated on the falling side of the RF waveform in conjunction with positive momentum compaction (R56) to compress the bunch. The success of this experiment motivated the design of a modified CEBAF-style arc with control of CSR and microbunching effects.« less

Light Vector Meson Photoproduction off of 1H at Jefferson Lab and p-w Interference in the Leptonic Decay Channel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Djalali, Chaden; Paolone, Michael; Weygand, Dennis

2014-09-01

Although the phenomena of r – w interference has been studied at great length in pionic decay channel over the past 50 years, a study of the interference in a purely electromagnetic production and decay channel has never been performed on an elementary proton target until now. The only published photo-production data of the r - w leptonic decay channel was obtained in the early seventies on C and Be. An investigation of the r - w interference on a Hydrogen was recently completed at Jefferson Lab with the CLAS detector. The di-lepton spectra was fit with two inter- feringmore » relativistic Breit-Wigner functions, and the interference phase was extracted. Preliminary results will be compared to the previous experimental studies in nuclei.« less

MCP-PMT studies at the High-B test facility at Jefferson Lab

DOE PAGES

Ilieva, Yordanka; Allison, Lee; Cao, Tongtong; ...

2016-03-30

Here we present preliminary results for the gain performance of commercially available 3- mum and 6- mum pore-size single-anode microchannel-plate photomultipliers (MCP PMTs) in magnetic fields up to 5 T and for various orientations of the sensor relative to the field direction. The measurements were performed at Thomas Jefferson National Accelerator Facility in Newport News, VA. Our results show that smaller-pore-size PMTs have better gain performance in magnetic fields. At various angles, the shape of the gain dependence on the strength of the magnetic field strongly depends on the type of the sensor. Also, for each sensor, the azimuthal dependencemore » is strongly correlated with the polar angle. Overall, the sensors exhibit a reasonable performance up to 2 T, although that upper limit depends on the sensor, the applied high voltage, and the orientation of the sensor relative to the field. To optimize the operational and design parameters of MCP PMTs for performance in high magnetic fields, further measurements and simulation studies will be pursued. Furthermore, our studies are part of an R&D for development of a Detector of Internally Reflected Cherenkov Light for the central detector of a future U.S. Electron Ion Collider.« less

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

NASA Astrophysics Data System (ADS)

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.

Dark Matter Search in a Beam-Dump eXperiment (BDX) at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battaglieri, M.

MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. This proposal presents the MeV-GeV DM discovery potential for amore » $$\\sim$$1 m$^3$ segmented CsI(Tl) scintillator detector placed downstream of the Hall A beam-dump at Jefferson Lab, receiving up to 10$$^{22}$$ electrons-on-target (EOT) in 285 days. This experiment (Beam-Dump eXperiment or BDX) would be sensitive to elastic DM-electron and to inelastic DM scattering at the level of 10 counts per year, reaching the limit of the neutrino irreducible background. The distinct signature of a DM interaction will be an electromagnetic shower of few hundreds of MeV, together with a reduced activity in the surrounding active veto counters. A detailed description of the DM particle $$\\chi$$ production in the dump and subsequent interaction in the detector has been performed by means of Monte Carlo simulations. Different approaches have been used to evaluate the expected backgrounds: the cosmogenic background has been extrapolated from the results obtained with a prototype detector running at INFN-LNS (Italy), while the beam-related background has been evaluated by GEANT4 Monte Carlo simulations. The proposed experiment will be sensitive to large regions of DM parameter space, exceeding the discovery potential of existing and planned experiments in the MeV-GeV DM mass range by up to two orders of magnitude.« less

The Search for Exotic Mesons in gamma p -> pi+pi+pi-n with CLAS at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Craig Bookwalter

2011-12-01

The {pi}{sub 1}(1600), a J{sup PC} = 1{sup {-+}} exotic meson has been observed by experiments using pion beams. Theorists predict that photon beams could produce gluonic hybrid mesons, of which the {pi}{sub 1}(1600) is a candidate, at enhanced levels relative to pion beams. The g12 rungroup at Jefferson Lab's CEBAF Large Acceptance Spectrometer (CLAS) has recently acquired a large photoproduction dataset, using a liquid hydrogen target and tagged photons from a 5.71 GeV electron beam. A partial-wave analysis of 502K {gamma}p {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -}n events selected from the g12 dataset has been performed, and preliminary fit resultsmore » show strong evidence for well-known states such as the a{sub 1}(1260), a{sub 2}(1320), and {pi}{sub 2}(1670). However, we observe no evidence for the production of the {pi}{sub 1}(1600) in either the partial-wave intensities or the relative complex phase between the 1{sup {-+}} and the 2{sup {-+}} (corresponding to the {pi}{sub 2}) partial waves.« less

Field Work Proposal: PUBLIC OUTREACH EVENT FOR ACCELERATOR STEWARDSHIP TEST FACILITY PILOT PROGRAM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hutton, Andrew; Areti, Hari

2015-03-05

Jefferson Lab’s outreach efforts towards the goals of Accelerator Stewardship Test Facility Pilot Program consist of the lab’s efforts in three venues. The first venue, at the end of March is to meet with the members of Virginia Tech Corporate Research Center (VTCRC) (http://www.vtcrc.com/tenant-directory/) in Blacksburg, Virginia. Of the nearly 160 members, we expect that many engineering companies (including mechanical, electrical, bio, software) will be present. To this group, we will describe the capabilities of Jefferson Lab’s accelerator infrastructure. The description will include not only the facilities but also the intellectual expertise. No funding is requested for this effort. Themore » second venue is to reach the industrial exhibitors at the 6th International Particle Accelerator Conference (IPAC’15). Jefferson Lab will host a booth at the conference to reach out to the >75 industrial exhibitors (https://www.jlab.org/conferences/ipac2015/SponsorsExhibitors.php) who represent a wide range of technologies. A number of these industries could benefit if they can access Jefferson Lab’s accelerator infrastructure. In addition to the booth, where written material will be available, we plan to arrange a session A/V presentation to the industry exhibitors. The booth will be hosted by Jefferson Lab’s Public Relations staff, assisted on a rotating basis by the lab’s scientists and engineers. The budget with IPAC’15 designations represents the request for funds for this effort. The third venue is the gathering of Southeastern Universities Research Association (SURA) university presidents. Here we plan to reach the research departments of the universities who can benefit by availing themselves to the infrastructure (material sciences, engineering, medical schools, material sciences, to name a few). Funding is requested to allow for attendance at the SURA Board Meeting. We are coordinating with DOE regarding these costs to raise the projected

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

NASA Astrophysics Data System (ADS)

Kneisel, P.; Ciovati, G.; Dhakal, P.; Saito, K.; Singer, W.; Singer, X.; Myneni, G. R.

2015-02-01

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 Eacc=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.

Experimental status DVCS e p ---> e p gamma and e n ---> e n gamma at Jefferson Lab-Hall A

DOE Office of Scientific and Technical Information (OSTI.GOV)

C. Ferdi

2004-06-02

The experiments E00-110 and E03-106 [1] propose to measure the Deep Virtual Compton Scattering process (DVCS) ep --> ep{gamma} and en --> en{gamma} in Hall A at Jefferson Lab with a 5.75 GeV longitudinally polarized electron beam. The exclusivity requires the High Resolution Spectrometer of the Hall A for the detection of the scattered electron ({Delta}p/p = 10^-4), an electromagnetic calorimeter for the detection of the real photon ({sigma}/E<5%) and a scintillator array for the detection of the third particle. A 1 GHz sampling system allows one to deal with pile-up as expected from running detectors at small angles andmore » high luminosity L = 10^37 cm^-2 s^-1. We will describe the apparatus and will explain the method to extract GPDs and evaluate the contributions from higher twists from the measurement of the cross-section difference.« less

Superconducting Magnet Power Supply and Hard-Wired Quench Protection at Jefferson Lab for 12 GeV Upgrade

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghoshal, Probir K.; Bachimanchi, Ramakrishna; Fair, Ruben J.

The superconducting magnet system in Hall B being designed and built as part of the Jefferson Lab 12 GeV upgrade requires powering two conduction cooled superconducting magnets - a torus and a solenoid. The torus magnet is designed to operate at 3770 A and solenoid at 2416 A. Failure Modes and Effects Analysis (FMEA) determined that voltage level thresholds and dump switch operation for magnet protection should be tested and analyzed before incorporation into the system. The designs of the quench protection and voltage tap sub-systems were driven by the requirement to use a primary hard-wired quench detection sub-system togethermore » with a secondary PLC-based protection. Parallel path voltage taps feed both the primary and secondary quench protection sub-systems. The PLC based secondary protection is deployed as a backup for the hard-wired quench detection sub-system and also acts directly on the dump switch. Here, we describe a series of tests and modifications carried out on the magnet power supply and quench protection system to ensure that the superconducting magnet is protected for all fault scenarios.« less

Superconducting Magnet Power Supply and Hard-Wired Quench Protection at Jefferson Lab for 12 GeV Upgrade

DOE PAGES

Ghoshal, Probir K.; Bachimanchi, Ramakrishna; Fair, Ruben J.; ...

2017-10-05

The superconducting magnet system in Hall B being designed and built as part of the Jefferson Lab 12 GeV upgrade requires powering two conduction cooled superconducting magnets - a torus and a solenoid. The torus magnet is designed to operate at 3770 A and solenoid at 2416 A. Failure Modes and Effects Analysis (FMEA) determined that voltage level thresholds and dump switch operation for magnet protection should be tested and analyzed before incorporation into the system. The designs of the quench protection and voltage tap sub-systems were driven by the requirement to use a primary hard-wired quench detection sub-system togethermore » with a secondary PLC-based protection. Parallel path voltage taps feed both the primary and secondary quench protection sub-systems. The PLC based secondary protection is deployed as a backup for the hard-wired quench detection sub-system and also acts directly on the dump switch. Here, we describe a series of tests and modifications carried out on the magnet power supply and quench protection system to ensure that the superconducting magnet is protected for all fault scenarios.« less

Harmonic Kicker RF Cavity for the Jefferson Lab Electron-Ion Collider EM Simulation, Modification, and Measurements

NASA Astrophysics Data System (ADS)

Overstreet, Sarah; Wang, Haipeng

2017-09-01

An important step in the conceptual design for the future Jefferson Lab Electron-Ion Collider (JLEIC) is the development of supporting technologies for the Energy Recovery Linac (ERL) Electron Cooling Facility. The Harmonic Radiofrequency (RF) kicker cavity is one such device that is responsible for switching electron bunches in and out of the Circulator Cooling Ring (CCR) from and to the ERL, which is a critical part of the ion cooling process. Last year, a half scale prototype of the JLEIC harmonic RF kicker model was designed with resonant frequencies to support the summation of 5 odd harmonics (95.26 MHz, 285.78 MHz, 476.30 MHz, 666.82 MHz, and 857.35 MHz); however, the asymmetry of the kicker cavity gives rise to multipole components of the electric field at the electron-beam axis of the cavity. Previous attempts to symmetrize the electric field of this asymmetrical RF cavity have been unsuccessful. The aim of this study is to modify the existing prototype for a uniform electric field across the beam pathway so that the electron bunches will experience nearly zero beam current loading. In addition to this, we have driven the unmodified cavity with the harmonic sum and used the wire stretching method for an analysis of the multipole electric field components.

Looking North into Lab Metallurgy Testing Area and Enrichment Motor ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Looking North into Lab Metallurgy Testing Area and Enrichment Motor within Recycle Recovery Building - Hematite Fuel Fabrication Facility, Recycle Recovery Building, 3300 State Road P, Festus, Jefferson County, MO

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

DOE PAGES

Kneisel, P.; Ciovati, G.; Dhakal, P.; ...

2014-12-01

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. The 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 mademore » 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 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.« less

Measurement of the Neutron Electric Form Factor GEN at High Q2

NASA Astrophysics Data System (ADS)

McCormick, Kathy

2003-01-01

Experiment E02-0131 at Thomas Jefferson National Accelerator Facility (Jefferson Lab) will measure the neutron electric form factor GEn at the high four-momentum transfer values of Q2 ≈ 1.3, 2.4 and 3.4 (GeV/c)2 via a measurement of the cross section asymmetry AT in the reaction {}3vec He(vec e, e'n)pp . This measurement was approved for 32 days of running by Jefferson Lab PAC 212 in January 2002.

Evaluation of Light Collection System for Pion and Kaon Experiments in Hall C at Jefferson Lab

NASA Astrophysics Data System (ADS)

Roustom, Salim

2017-09-01

The neutral pion and the kaon are opportune to study the hadron structure through General Parton Distributions, which can be viewed as spatial densities at different momenta of the quarks inside the proton. To study hadron structure with pion or kaon experiments in Hall C at 12 GeV Jefferson Lab, one must analyze the final state neutral pions and kaons and their decay products. For the analysis of these particles, dedicated detectors based on the Cherenkov or scintillation mechanism are used, e.g. the HMS and SHMS aerogel detectors and the PbWO4-based Neutral Particle Spectrometer. A critical part of these detectors is the light collection system. Photomultiplier Tubes (PMTs) have many advantages, however, they are sensitive to magnetic fields and can get damaged by elevated helium levels in the atmosphere. An alternative to PMTs are Avalanche Photodiodes (APDs). APDs are sensitive to background noise, temperature, and radiation. It is thus important to evaluate the benefits of each light collection system and optimize operating conditions to ensure performance over a reasonably long time. I will present a performance study of PMTs exposed to elevated levels of helium and a comparison of APDs as alternatives, as well as new, compact readout methods. Supported in part by NSF Grants PHY-1714133, PHY-1530874, PHY-1306227 and PHY-1306418.

An Exploratory Study of γp -> ϕ (K+K-) ω (π+π-π0) p in the GlueX Experiment at Jefferson Lab

NASA Astrophysics Data System (ADS)

Banks, Christopher; Salgado, Carlos; GlueX Collaboration

Mesons are subatomic particles that have intermediate masses between electrons and protons and manifest as quark-antiquark pairs kept together by the strong force (gluons). Quantum Chromodynamics (QCD) states the possibility for mesons manifested only as gluons (glueballs) or as quarks and gluons (hybrids). Some of those hybrid mesons could have quantum numbers that are inaccessible to conventional mesons (exotics). The GlueX detector at Jefferson Lab was built to search for exotic mesons at intermediate energies (2-3 GeV masses). The reaction γp -> ϕ (K+K-) ω (π+π-π0) p is of interest for this study. By simulating the detector and the reconstruction acceptance and efficiency, and by using expected signals and backgrounds through a detailed Monte Carlo, we have studied the possibilities of observing this reaction with the present GlueX configuration. Department of Energy (DOE).

Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab: an update on PR12-16-001

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battaglieri, M.

This document is an update to the proposal PR12-16-001 Dark matter search in a Beam-Dump eXperiment (BDX) at Jefferson Lab submitted to JLab-PAC44 in 2016 reporting progress in addressing questions raised regarding the beam-on backgrounds. The concerns are addressed by adopting a new simulation tool, FLUKA, and planning measurements of muon fluxes from the dump with its existing shielding around the dump. First, we have implemented the detailed BDX experimental geometry into a FLUKA simulation, in consultation with experts from the JLab Radiation Control Group. The FLUKA simulation has been compared directly to our GEANT4 simulations and shown to agreemore » in regions of validity. The FLUKA interaction package, with a tuned set of biasing weights, is naturally able to generate reliable particle distributions with very small probabilities and therefore predict rates at the detector location beyond the planned shielding around the beam dump. Second, we have developed a plan to conduct measurements of the muon ux from the Hall-A dump in its current configuration to validate our simulations.« less

Use of simple x-ray measurement in the performance analysis of cryogenic RF accelerator cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

D. Dotson; M. Drury; R. May

X-ray emission by radiofrequency (RF) resonant cavities has long been known to accelerator health physicists as a potentially serious source of radiation exposure. The authors points out the danger of klystrons and microwave cavities by stating that the radiation source term is erratic and may be unpredictable depending on microscopic surface conditions which change with time. He also states the x-ray output is a rapidly increasing function of RF input power. At Jefferson Lab, the RF cavities used to accelerate the electron beam employ superconducting technology. X-rays are emitted at high cavity gradients, and measurements of cavity x-rays are valuablemore » for health physics purposes and provide a useful diagnostic tool for assessing cavity performance. The quality factor (Q) for superconducting RF resonant cavities used at Jefferson Lab, is typically 5 x 10{sup 9} for the nominal design gradient of 5 MVm{sup {minus}1}. This large value for Q follows from the small resistive loss in superconducting technology. The operating frequency is 1,497 MHz. In the absence of beam, the input power for a cavity is typically 750 W and the corresponding dissipated power is 2.6 W. At 5 MWm{sup {minus}1}, the input power is 3 kW fully beam loaded. At higher gradients, performance degradation tends to occur due to the onset of electron field emission from defects in the cavity.« less

The MØLLER experiment at Jefferson Lab: search for physics beyond the Standard Model

NASA Astrophysics Data System (ADS)

van Oers, Willem T. H.

2010-07-01

The MO/LLER experiment at Jefferson Lab will measure the parity-violating analyzing power Az in the scattering of 11 GeV longitudinally polarized electrons from the atomic electrons in a liquid hydrogen target (Mo/ller scattering). In the Standard Model a non-zero Az is due to the interference of the electromagnetic amplitude and the weak neutral current amplitude, the latter mediated by the Z0 boson. Az is predicted to be 35.6 parts per billion (ppb) at the kinematics of the experiment. It is the objective of the experiment to measure Az to a precision of 0.73 ppb. This result would yield a measurement of the weak charge of the electron QWe to a fractional error of 2.3% at an average value Q2 of 0.0056 (GeV/c)2. This in turn will yield a determination of the weak mixing angle sin2θw with an uncertainty of ±0.00026(stat) ±0.00013(syst), comparable to the accuracy of the two best determinations at high energy colliders (at the Z0 pole). Consequently, the result could potentially influence the central value of this fundamental electroweak parameter, which is of critical importance in deciphering any signal of new physics that might be observed at the Large Hadron Collider (LHC). The measurement is sensitive to the interference of the electromagnetic amplitude with new neutral current amplitudes as weak as 10-3 GF from as yet unknown high energy dynamics, a level of sensitivity unlikely to be matched in any experiment measuring a flavor and CP conserving process in the next decade. This provides indirect access to new physics at multi-TeV scales in a manner complementary to direct searches at the LHC.

NBodyLab Simulation Experiments with GRAPE-6a AND MD-GRAPE2 Acceleration

NASA Astrophysics Data System (ADS)

Johnson, V.; Ates, A.

2005-12-01

NbodyLab is an astrophysical N-body simulation testbed for student research. It is accessible via a web interface and runs as a backend framework under Linux. NbodyLab can generate data models or perform star catalog lookups, transform input data sets, perform direct summation gravitational force calculations using a variety of integration schemes, and produce analysis and visualization output products. NEMO (Teuben 1994), a popular stellar dynamics toolbox, is used for some functions. NbodyLab integrators can optionally utilize two types of low-cost desktop supercomputer accelerators, the newly available GRAPE-6a (125 Gflops peak) and the MD-GRAPE2 (64-128 Gflops peak). The initial version of NBodyLab was presented at ADASS 2002. This paper summarizes software enhancements developed subsequently, focusing on GRAPE-6a related enhancements, and gives examples of computational experiments and astrophysical research, including star cluster and solar system studies, that can be conducted with the new testbed functionality.

Final Assembly and Factory Testing of the Jefferson Lab SHMS Spectrometer Quadrupole and Dipole Superconducting Magnets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brindza, Paul; Lassiter, Steven; Sun, Eric

Jefferson Lab is constructing an 11 Gev/c electron spectrometer called the Super High Momentum Spectrometer (SHMS) as part of the 12 GeV JLAB upgrade for experimental Hall C. Three of the five superconducting(SC) SHMS magnets are under construction at SigmaPhi in Vannes France as a result of an international competition for design and fabrication. The three magnets Q2 and Q3 60 cm bore quadrupoles and the 60 cm warm bore dipole are complete or near complete and have many design features in common. All three magnets share a common superconductor, collaring system, cryostat design, cold to warm support, cryogenic interface,more » burnout resistant current leads, DC power supply, quench protection, instrumentation and controls. The three magnets are collared, installed in cryostats and welded up and in various stages of final testing. The Q2 quadrupole is due to ship from France to America in August arriving during this ASC conference and has passed all final hipot, leak and pressure tests. The dipole is in leak and pressure testing as of July 2016 while the Q3 quadrupole requires some outer vacuum vessel assembly. Delivery of the Q3 and Dipole magnets will follow the Q2 at about 1 month intervals. Lastly, factory testing have included hipot and electrical tests, magnetic tests at low field, mechanical alignments to center the coils, leak tests and ASME Code required pressure tests. Upon installation in Hall C at JLAB cold testing will commence.« less

Final Assembly and Factory Testing of the Jefferson Lab SHMS Spectrometer Quadrupole and Dipole Superconducting Magnets

DOE PAGES

Brindza, Paul; Lassiter, Steven; Sun, Eric; ...

2017-06-01

Jefferson Lab is constructing an 11 Gev/c electron spectrometer called the Super High Momentum Spectrometer (SHMS) as part of the 12 GeV JLAB upgrade for experimental Hall C. Three of the five superconducting(SC) SHMS magnets are under construction at SigmaPhi in Vannes France as a result of an international competition for design and fabrication. The three magnets Q2 and Q3 60 cm bore quadrupoles and the 60 cm warm bore dipole are complete or near complete and have many design features in common. All three magnets share a common superconductor, collaring system, cryostat design, cold to warm support, cryogenic interface,more » burnout resistant current leads, DC power supply, quench protection, instrumentation and controls. The three magnets are collared, installed in cryostats and welded up and in various stages of final testing. The Q2 quadrupole is due to ship from France to America in August arriving during this ASC conference and has passed all final hipot, leak and pressure tests. The dipole is in leak and pressure testing as of July 2016 while the Q3 quadrupole requires some outer vacuum vessel assembly. Delivery of the Q3 and Dipole magnets will follow the Q2 at about 1 month intervals. Lastly, factory testing have included hipot and electrical tests, magnetic tests at low field, mechanical alignments to center the coils, leak tests and ASME Code required pressure tests. Upon installation in Hall C at JLAB cold testing will commence.« less

ALON® Components With Tunable Dielectric Properties for High Power Accelerator Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goldman, Lee M; Jha, Santosh K; Lobur, Nicole

There are challenges in linear particle accelerators associated with the need to suppress “higher order modes” (HOMs). HOMs are detrimental to accelerator operation as they are a source of beam instability. The absorption/suppression of HOMs and dissipation of the energy of higher order modes is vital to the function of these accelerators. Surmet has identified ALON® Optical Ceramic (Aluminum Oxynitride), a hard, durable ceramic that is fabricated through conventional powder processing techniques, as a potential material for HOM absorber. In this Phase I program, Surmet has produced new ALON-composite HOM absorber materials that function at both ambient and cryogenic temperatures.more » The composite materials were developed and evaluated in collaboration with Thomas Jefferson National Labs. Success in this Phase I and the potential Phase II will demonstrate the utility of ALON composite components for RF absorbing applications and lay the groundwork for commercialization of such products, with applications in basic science, medical and digital electronics industries.« less

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

NASA Astrophysics Data System (ADS)

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.

Deep Exclusive Pseudoscalar Meson Production at Jefferson Lab Hall C

DOE Office of Scientific and Technical Information (OSTI.GOV)

Basnet, Samip

2017-09-01

Measurements of exclusive meson production are a useful tool in the study of hadronic structure. In particular, one can discern the relevant degrees of freedom at different distance scales through these studies. In the transition region between low momentum transfer (where a description of hadronic degrees of freedom in terms of effective hadronic Lagrangians is valid) and high momentum transfer (where the degrees of freedom are quarks and gluons), the predictive power of Quantum Chromodynamics (QCD), the theory of the strong interaction, is limited due to the absence of a complete solution. Thus, one has to rely upon experimental datamore » from the non-perturbative intermediate-energy regime to thoroughly understand the onset of perturbative QCD (pQCD) as the momentum transfer is increased. This work involves two deep exclusive meson electroproduction experiments at Jefferson Lab (JLab). The p(e,e'pi+)n reaction is studied at fixed Q^2 and W of 2.5 GeV2 and 2.0 GeV, respectively, while varying the four momentum transfer to the nucleon -t from 0.2 to 2.1 GeV2 . As -t is increased, the hadronic interaction scale is reduced independently of the observation scale of the virtual photon, providing valuable information about the hard- scattering process in general. The data was taken at JLab Hall C in 2003, as a part of the experiment E01-004, Fpi-2, using the High Momentum Spectrometer (HMS) and Short Orbit Spectrometer (SOS), and in this work, the results of the differential cross section analysis are presented and compared to prior data, as well as two theoretical models. Using these results over a wide -t range, the transition from hard to soft QCD is also studied. In addition, the p(e,e'K+)Lambda(Sigma0) reactions are also studied. Despite their importance in elucidating the reaction mechanism underlying strangeness production, we still do not have complete understanding of these reactions above the resonance region. The experiment, E12- 09-011, intends to

Pulsed-focusing recirculating linacs for muon acceleration

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Rolland

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 arcsmore » 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

Is Jefferson a Founding Father of Democratic Education? A Response to "Jefferson and the Ideology of Democratic Schooling"

ERIC Educational Resources Information Center

Neem, Johann

2013-01-01

This response argues that it is reasonable to consider Thomas Jefferson a proponent of democratic education. It suggests that Jefferson's education proposals sought to ensure the wide distribution of knowledge and that Jefferson's legacy remains important to us today.

18. VIEW OF THE GENERAL CHEMISTRY LAB. THE LABORATORY PROVIDED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

18. VIEW OF THE GENERAL CHEMISTRY LAB. THE LABORATORY PROVIDED GENERAL ANALYTICAL AND STANDARDS CALIBRATION, AS WELL AS DEVELOPMENT OPERATIONS INCLUDING WASTE TECHNOLOGY DEVELOPMENT AND DEVELOPMENT AND TESTING OF MECHANICAL SYSTEMS FOR WEAPONS SYSTEMS. (4/4/66) - Rocky Flats Plant, General Manufacturing, Support, Records-Central Computing, Southern portion of Plant, Golden, Jefferson County, CO

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.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crooks, Roy

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.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Penel-Nottaris, Emilie

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.

Betatron radiation based diagnostics for plasma wakefield accelerated electron beams at the SPARC_LAB test facility

NASA Astrophysics Data System (ADS)

Shpakov, V.; Anania, M. P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Curcio, A.; Dabagov, S.; Ferrario, M.; Filippi, F.; Marocchino, A.; Paroli, B.; Pompili, R.; Rossi, A. R.; Zigler, A.

2016-09-01

Recent progress with wake-field acceleration has shown a great potential in providing high gradient acceleration fields, while the quality of the beams remains relatively poor. Precise knowledge of the beam size at the exit from the plasma and matching conditions for the externally injected beams are the key for improvement of beam quality. Betatron radiation emitted by the beam during acceleration in the plasma is a powerful tool for the transverse beam size measurement, being also non-intercepting. In this work we report on the technical solutions chosen at SPARC_LAB for such diagnostics tool, along with expected parameters of betatron radiation.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laine, Vivien E.

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 inmore » 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.« less

E00-110 experiment at Jefferson Lab Hall A: Deeply virtual Compton scattering off the proton at 6 GeV

DOE PAGES

Defurne, M.; Amaryan, M.; Aniol, K. A.; ...

2015-11-03

We present final results on the photon electroproduction (more » $$\\vec{e}p\\rightarrow ep\\gamma$$) cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region from Jefferson Lab experiment E00-110. Results from an analysis of a subset of these data were published before, but the analysis has been improved which is described here at length, together with details on the experimental setup. Furthermore, additional data have been analyzed resulting in photon electroproduction cross sections at new kinematic settings, for a total of 588 experimental bins. Results of the $Q^2$- and $$x_B$$-dependences of both the helicity-dependent and helicity-independent cross sections are discussed. The $Q^2$-dependence illustrates the dominance of the twist-2 handbag amplitude in the kinematics of the experiment, as previously noted. Thanks to the excellent accuracy of this high luminosity experiment, it becomes clear that the unpolarized cross section shows a significant deviation from the Bethe-Heitler process in our kinematics, compatible with a large contribution from the leading twist-2 DVCS$^2$ term to the photon electroproduction cross section. The necessity to include higher-twist corrections in order to fully reproduce the shape of the data is also discussed. The DVCS cross sections in this study represent the final set of experimental results from E00-110, superseding the previous publication.« less

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kondratenko, A.; Kondratenko, M.; Filatov, Yu. N.

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 dependsmore » 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.« less

Mott Polarimeter Upgrade at Jefferson Lab

NASA Astrophysics Data System (ADS)

McHugh, M.; Opper, A. K.; Grames, J.; Poelker, M.; Suleiman, R.; Horowitz, C.; Rhodes, S.; Roca Maza, X.; Sinclair, C.

2013-10-01

A Mott polarimeter with a design optimized for 5.5 MeV/c has been in routine use at the CEBAF accelerator for well over a decade, providing polarization measurements approaching 1% accuracy. Measurements with different target elements (Au, Ag, Cu) over decades of target thicknesses (100 - 10,000 angstroms), and beam energies between 2 and 8 MeV allow us to determine the effective analyzing power with a high degree of certainty. Recent and planned improvements in our polarimeter configuration, detectors and data acquisition system, coupled with a low 31 MHz repetition rate beam allow us to distinguish and suppress electrons that do not originate from the target foil. This work coupled with a significant effort to produce a detailed GEANT4 model of the polarimeter is part of an effort to determine systematic uncertainties at the level of the theoretically calculated analyzing power. We describe our activities and a series of planned measurements that will allow us to demonstrate and possibly improve the precision and accuracy of polarization measurements at JLab, as required for future parity violation experiments.

Gain Evaluation of Micro-Channel-Plate Photomultipliers in the Upgraded High-B Test Facility at Jefferson Lab

NASA Astrophysics Data System (ADS)

Barber, Corinne; DIRC at EIC Collaboration

2015-10-01

The High-B test facility at Thomas Jefferson National Accelerator Facility allows researchers to evaluate the gain of compact photon sensors, such as Micro-Channel-Plate Photomultipliers (MCP-PMTs), in magnetic fields up to 5 T. These ongoing studies support the development of a Detector of Internally Reflected Cherenkov light (DIRC) to be used in an Electron Ion Collider (EIC). Here, we present our summer 2015 activities to upgrade and improve the facility, and we show results for MCP-PMT gain changes in high B-fields. To monitor the light stability delivered to the MCP-PMTs being tested, we implemented a Silicon Photomultiplier (SiPM) in the setup and calibrated the ADC reading this sensor. A 405-nm Light-Emitting Diode (LED) housed in an optical tube compatible with neutral density filters was also installed. The filters provide an alternative way of reducing the light output of the LED to operate the MCP-PMTs in a single-photon mode. We calibrated a set of filters by means of a photodiode and measured the photon flux at multiple positions relative to the LED. This information helped us to design 3D-printed holders unique to each MCP-PMT so that the photocathode receives the greatest amount of light. The improvements to the setup allow for more precise PMT gain evaluation. This team includes 7 collaborators/co-authors besides myself: Yordanka Ilieva, Kijun Park, Greg Kalicy, Carl Zorn, Pawel Nadel-Turonski, Tongtong Cao, and Lee.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mcguckin, Theodore

2008-10-01

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 machinemore » 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 (including a discussion of« less

A prototype of a beam steering assistant tool for accelerator operations

DOE Office of Scientific and Technical Information (OSTI.GOV)

M. Bickley; P. Chevtsov

2006-10-24

The CEBAF accelerator provides nuclear physics experiments at Jefferson Lab with high quality electron beams. Three experimental end stations can simultaneously receive the beams with different energies and intensities. For each operational mode, the accelerator setup procedures are complicated and require very careful checking of beam spot sizes and positions on multiple beam viewers. To simplify these procedures and make them reproducible, a beam steering assistant GUI tool has been created. The tool is implemented as a multi-window control screen. The screen has an interactive graphical object window, which is an overlay on top of a digitized live video imagemore » from a beam viewer. It allows a user to easily create and edit any graphical objects consisting of text, ellipses, and lines, right above the live beam viewer image and then save them in a file that is called a beam steering template. The template can show, for example, the area within which the beam must always be on the viewer. Later, this template can be loaded in the interactive graphical object window to help accelerator operators steer the beam to the specified area on the viewer.« less

Di-hadron production at Jefferson Laboratory

NASA Astrophysics Data System (ADS)

Anefalos Pereira, Sergio; CLAS Collaboration

2015-04-01

Semi-inclusive deep inelastic scattering (SIDIS) has been used extensively in recent years as an important testing ground for QCD. Studies so far have concentrated on better determination of parton distribution functions, distinguishing between the quark and antiquark contributions, and understanding the fragmentation of quarks into hadrons. Pair of hadrons (di-hadron) SIDIS provides information on the nucleon structure and hadronization dynamics that complements single-hadron SIDIS. The study of di-hadrons allow us to study higher twist distribution functions and Dihadron Fragmentation Functions (DiFF). Together with the twist-2 PDFs (f 1, g 1, h 1), the Higher Twist (HT) e and hL functions are very interesting because they offer insights into the physics of the largely unexplored quark-gluon correlations which provide direct and unique insights into the dynamics inside hadrons. The CLAS spectrometer, installed in Hall-B at Jefferson Lab, has collected data using the CEBAF 6 GeV longitudinally polarized electron beam on longitudinally polarized solid NH3 targets. Preliminary results on beam-, target- and double-spin asymmetries will be presented.

Window Details U.S. Veterans Hospital, Jefferson Barracks, Therapeutic Exercise ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Window Details - U.S. Veterans Hospital, Jefferson Barracks, Therapeutic Exercise Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Landscape Plan U.S. Veterans Hospital, Jefferson Barracks, Therapeutic Exercise ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Landscape Plan - U.S. Veterans Hospital, Jefferson Barracks, Therapeutic Exercise Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

First Floor Plan U.S. Veterans Hospital, Jefferson Barracks, Therapeutic ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

First Floor Plan - U.S. Veterans Hospital, Jefferson Barracks, Therapeutic Exercise Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

North and South Elevations U.S. Veterans Hospital, Jefferson Barracks, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

North and South Elevations - U.S. Veterans Hospital, Jefferson Barracks, Therapeutic Exercise Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Southwest corner, looking north U.S. Veterans Hospital, Jefferson Barracks, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Southwest corner, looking north - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

North wall, looking southeast U.S. Veterans Hospital, Jefferson Barracks, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

North wall, looking southeast - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Basement, bathroom, looking south U.S. Veterans Hospital, Jefferson Barracks, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Basement, bathroom, looking south - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Northeast corner, looking southwest U.S. Veterans Hospital, Jefferson Barracks, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Northeast corner, looking southwest - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Interior, rear sunporch, looking north U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior, rear sunporch, looking north - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

South (front) wall, looking northwest U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

South (front) wall, looking northwest - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Interior, east bedroom, looking southeast U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior, east bedroom, looking southeast - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Interior, living room, looking west U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior, living room, looking west - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Interior, dining room, looking southeast U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Interior, dining room, looking southeast - U.S. Veterans Hospital, Jefferson Barracks, Medical Officer in Charge Residence, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Southeast corner, looking northwest U.S. Veterans Hospital, Jefferson Barracks, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Southeast corner, looking northwest - U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

West wall, looking northeast U.S. Veterans Hospital, Jefferson Barracks, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

West wall, looking northeast - U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Ground Floor Plan (Section A) U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Ground Floor Plan (Section A) - U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Ground Floor Plan (Section B) U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Ground Floor Plan (Section B) - U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

First Floor Plan (Section A) U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

First Floor Plan (Section A) - U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

First Floor Plan (Section B) U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

First Floor Plan (Section B) - U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Second Floor Plan (Section A) U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Second Floor Plan (Section A) - U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Second Floor Plan (Section B) U.S. Veterans Hospital, Jefferson ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Second Floor Plan (Section B) - U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

The Science and Experimental Equipment for the 12 GeV Upgrade of CEBAF

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arrington, John; Bernstein, Aron; Brooks, William

2005-01-10

This Conceptual Design Report (CDR) presents the compelling scientific case for upgrading the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab to 12 GeV. Such a facility will make profound contributions to the study of hadronic matter.

U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

U.S. Veterans Hospital, Jefferson Barracks, Spinal Cord Injury Unit and Tuberculosis Neuropsychiatric Building, VA Medical Center, Jefferson Barracks Division 1 Jefferson Barracks Drive, Saint Louis, Independent City, MO

Chapter in book "Many Body Structure of Strongly Interacting Systems, Refereed and Selected Contributions from the Symposium '20 Years of Physics at the Mainz Microtron MAMI,'" Part I, Editors: Arenhövel, H.; Backe, H.; Drechsel, D.; Friedrich, J.; Kaiser, K.-H.; Walcher, Th., p.7-17 (contribution entitled Physics at the Thomas Jefferson National Accelerator Facility)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawrence Cardman

2006-09-01

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 electron and photon beams. Selected experimental results of particular interest to the MAMI community are presented.

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

ERIC Educational Resources Information Center

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…

Experimental Setup and Commissioning of a Test Facility for Gain Evaluation of Microchannel-Plate Photomultipliers in High Magnetic Field at Jefferson Lab

NASA Astrophysics Data System (ADS)

Bringley, Eric; Cao, Tongtong; Ilieva, Yordonka; Nadel-Turonski, Pawel; Park, Kijun; Zorn, Carl

2014-09-01

At the Thomas Jefferson National Accelerator Facility (JLab) a research and development project for a Detector of Internally-Reflected Cherenkov light for the upcoming Electron Ion Collider is underway. One goal is the development of a compact readout camera that can operate in high magnetic fields. Small-size photon sensors, such as Microchannel-Plate Photomultipliers (MCP-PMT), are key components of the readout. Here we present our work to set up and commission a dedicated test facility at JLab where MCP-PMT gain is evaluated in magnetic fields of up to 5 T, and to develop a test procedure and analysis software to determine the gain. We operate the setup in a single-photon mode, where a light-emitting diode delivers photons to the sensor's photocathode. The PMT spectrum is measured with a flash Analog-to-Digital converter (fADC). We model the spectrum as a sum of an exponential background and a convolution of Poisson and Gaussian distributions of the pedestal and multiple photoelectron peaks, respectively. We determine the PMT's gain from the position of the single-photoelectron peak obtained by fitting the fADC spectrum to the model. Our gain uncertainty is <10%. The facility is now established and will have a long-lasting value for sensor tests and beyond-nuclear-physics applications.

Measuring GE^n at High Momentum Transfer

NASA Astrophysics Data System (ADS)

Feuerbach, Robert

2006-11-01

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 of the electric to magnetic form-factors of the neutron, 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 in-beam polarizations in excess of 50%. A medium acceptance (80msr) open-geometry magnetic spectrometer (BigBite) detected the scattered electron, while a newly contructed neutron detector observed 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.

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

NASA Astrophysics Data System (ADS)

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.

Proposal for a slow positron facility at Jefferson National Laboratory

NASA Astrophysics Data System (ADS)

Mills, Allen P.

2018-05-01

One goal of the JPos-17 International Workshop on Physics with Positrons was to ascertain whether it would be a good idea to expand the mission of the Thomas Jefferson National Accelerator Facility (JLab) to include science with low energy (i.e. "slow") spin polarized positrons. It is probably true that experimentation with slow positrons would potentially have wide-ranging benefits comparable to those obtained with neutron and x-ray scattering, but it is certain that the full range of these benefits will never be fully available without an infrastructure comparable to that of existing neutron and x-ray facilities. The role for Jefferson Laboratory would therefore be to provide and maintain (1) a dedicated set of machines for making and manipulating high intensity, high brightness beams of polarized slow positrons; (2) a suite of unique and easily used instruments of wide utility that will make efficient use of the positrons; and (3) a group of on-site positron scientists to provide scientific leadership, instrument development, and user support. In this note some examples will be given of the science that might make a serious investment in a positron facility worthwhile. At the same time, the lessons learned from various proposed and successful positron facilities will be presented for consideration.

Capture, acceleration and bunching rf systems for the MEIC booster and storage rings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Shaoheng; Guo, Jiquan; Lin, Fanglei

2015-09-01

The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. The electron collider ring accepts electrons from CEBAF at energies from 3 to 12 GeV. Protons and ions are delivered to a booster and captured in a long bunch before being ramped and transferred to the ion collider ring. The ion collider ring accelerates a small number of long ion bunches to colliding energy before they are re-bunched into a high frequency train of very short bunches for colliding. Two sets of low frequency RF systems are needed for the long ion bunch energymore » ramping in the booster and ion collider ring. Another two sets of high frequency RF cavities are needed for re-bunching in the ion collider ring and compensating synchrotron radiation energy loss in the electron collider ring. The requirements from energy ramping, ion beam bunching, electron beam energy compensation, collective effects, beam loading and feedback capability, RF power capability, etc. are presented. The preliminary designs of these RF systems are presented. Concepts for the baseline cavity and RF station configurations are described, as well as some options that may allow more flexible injection and acceleration schemes.« less

Continuous wave superconducting radio frequency electron linac for nuclear physics research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reece, Charles E.

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 itsmore » early beginnings to the commissioning of the 12 GeV era.« less

Continuous wave superconducting radio frequency electron linac for nuclear physics research

DOE PAGES

Reece, Charles E.

2016-12-28

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 itsmore » early beginnings to the commissioning of the 12 GeV era.« less

Beam Dynamics Considerations in Electron Ion Colliders

NASA Astrophysics Data System (ADS)

Krafft, Geoffrey

2015-04-01

The nuclear physics community is converging on the idea that the next large project after FRIB should be an electron-ion collider. Both Brookhaven National Lab and Thomas Jefferson National Accelerator Facility have developed accelerator designs, both of which need novel solutions to accelerator physics problems. In this talk we discuss some of the problems that must be solved and their solutions. Examples in novel beam optics systems, beam cooling, and beam polarization control will be presented. Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

Breakthrough: Record-Setting Cavity

ScienceCinema

Ciovati, Gianluigi

2018-02-06

Gianluigi "Gigi" Ciovati, a superconducting radiofrequency scientist, discusses how scientists at the U.S. Department of Energy's Jefferson Lab in Newport News, VA, used ARRA funds to fabricate a niobium cavity for superconducting radiofrequency accelerators that has set a world record for energy efficiency. Jefferson Lab's scientists developed a new, super-hot treatment process that could soon make it possible to produce cavities more quickly and at less cost, benefitting research and healthcare around the world. Accelerators are critical to our efforts to study the structure of matter that builds our visible universe. They also are used to produce medical isotopes and particle beams for diagnosing and eradicating disease. And they offer the potential to power future nuclear power plants that produce little or no radioactive waste.around the world. Accelerators are critical to our efforts to study the structure of matter that builds our visible universe. They also are used to produce medical isotopes and particle beams for diagnosing and eradicating disease. And they offer the potential to power future nuclear power plants that produce little or no radioactive waste.

1. Title Sheet Jefferson's Academical Village, Bounded by University ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

1. Title Sheet - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

2. 1827 Landscape Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. 1827 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

14. 2013 Landscape Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

14. 2013 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

5. 1880 Landscape Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. 1880 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

11. 1981 Landscape Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

11. 1981 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

7. 1914 Landscape Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

7. 1914 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

9. 1947 Landscape Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

9. 1947 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

3. 1860 Landscape Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

3. 1860 Landscape Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

8. 1914 Tree Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

8. 1914 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

6. 1880 Tree Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

6. 1880 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

4. 1860 Tree Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

4. 1860 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

10. 1947 Tree Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. 1947 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

12. 1981 Tree Plan Jefferson's Academical Village, Bounded by ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

12. 1981 Tree Plan - Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

First report of Jefferson's ground sloth (Megalonyx jeffersonii) in North Dakota: Paleobiogeographical and paleoecological significance

USGS Publications Warehouse

Hoganson, J.W.; McDonald, H. Gregory

2007-01-01

A well-preserved ungual of a pes documents the presence of Jefferson's ground sloth (Megalonyx jeffersonii) at the end of the Wisconsinan in North Dakota. This is the 1st report of M. jeffersonii in North Dakota, and one of few records from the upper Great Plains. An accelerator mass spectrometer radiocarbon age of 11,915 ?? 40 years ago was obtained from the specimen, suggesting that the sloth resided in North Dakota during the Rancholabrean Land Mammal Age, just before extinction of the species. Palynological records from sites near the sloth occurrence and of the same age indicate that it resided in a cool, moist, spruce-dominated forest habitat in a riparian setting along the Missouri River. Its presence in that setting corroborates the notion that Jefferson's ground sloth was a browsing inhabitant of gallery forests associated with rivers. It is likely that M. jeffersonii used river valleys, such as the Missouri River valley, as migration routes. ?? 2007 American Society of Mammalogists.

Jefferson and Democratic Education

ERIC Educational Resources Information Center

Holowchak, M. Andrew

2014-01-01

This essay is a reply to James Carpenter's "Thomas Jefferson and the Ideology of Democratic Schooling." In it, I argue that there is an apophatic strain in the essay that calls into question the motivation for the undertaking.

PCaPAC 2006 Proceedings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pavel Chevtsov; Matthew Bickley

2007-03-30

The 6-th international PCaPAC (Personal Computers and Particle Accelerator Controls) workshop was held at Jefferson Lab, Newport News, Virginia, from October 24-27, 2006. The main objectives of the conference were to discuss the most important issues of the use of PCs and modern IT technologies for controls of accelerators and to give scientists, engineers, and technicians a forum to exchange the ideas on control problems and their solutions. The workshop consisted of plenary sessions and poster sessions. No parallel sessions were held.Totally, more than seventy oral and poster presentations as well as tutorials were made during the conference, on themore » basis of which about fifty papers were submitted by the authors and included in this publication. This printed version of the PCaPAC 2006 Proceedings is published at Jefferson Lab according to the decision of the PCaPAC International Program Committee of October 26, 2006.« less

396. MIRACLE REVIVAL TEAM PENTECOSTAL CHURCH AT 2031 WEST JEFFERSON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

396. MIRACLE REVIVAL TEAM PENTECOSTAL CHURCH AT 2031 WEST JEFFERSON STREET, WEST SIDE - Russell Neighborhood, Bounded by Congress & Esquire Alley, Fifteenth & Twenty-first Streets, Louisville, Jefferson County, KY

75 FR 81640 - President William Jefferson Clinton Birthplace Home National Historic Site

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-28

... Jefferson Clinton Birthplace Home National Historic Site AGENCY: National Park Service, Interior. ACTION..., Hope, Arkansas 71801, as the ``President William Jefferson Clinton Birthplace Home National Historic... Birthplace Foundation, Inc., fee simple, unencumbered title to the William Jefferson Clinton Birthplace Home...

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

USGS Publications Warehouse

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.

Jefferson's Academical Village, Bounded by University Avenue on the north, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

Jefferson's Academical Village, Bounded by University Avenue on the north, Jefferson Park Avenue on the south, Hospital Drive on the east, and McCormick Road on the west, Charlottesville, Independent City, VA

Measurement of differential cross sections and spin density matrix elements along with a partial wave analysis for gammap → po using CLAS at Jefferson Lab

NASA Astrophysics Data System (ADS)

Williams, Mike

This work presents measurements of differential cross sections, dsigma/dcos qwCM , and spin density matrix elements, r0MM' , for the reaction gammap → po in the energy range 1.72 GeV< s <2.84 GeV. The data were collected at Jefferson Lab, using the CLAS detector, as part of the g11a run period in 2004. Our r0MM' measurements vastly increase the precision of the world's data and extend the large angle measurements by over 400 MeV in s . Our data confirms that for s < 2.1 GeV, the forward angle (small |t|) production amplitude is dominated by t-channel pi0 exchange. At higher energies, existing non-resonant models do a poor job of describing our data. In particular, u-channel models fail to reproduce our highest energy backwards r0MM' measurements. A mass-independent partial wave analysis has also been performed. Near threshold, the dominant resonance contributions extracted are the **** F15 (1680) and *** D 13(1700). Together with the t-channel pi0 exchange, these three waves provide a remarkably good description of our differential cross section and spin density matrix element measurements for s < 2 GeV. Strong, but not conclusive, evidence for the **** G17(2190) has also been extracted. Improved non-resonant models may be necessary to irrefutably show whether this state contributes to o photoproduction. Evidence for missing resonances is suggestive, but inconclusive without theoretical input.

EPICS Channel Access Server for LabVIEW

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhukov, Alexander P.

It can be challenging to interface National Instruments LabVIEW (http://www.ni.com/labview/) with EPICS (http://www.aps.anl.gov/epics/). Such interface is required when an instrument control program was developed in LabVIEW but it also has to be part of global control system. This is frequently useful in big accelerator facilities. The Channel Access Server is written in LabVIEW, so it works on any hardware/software platform where LabVIEW is available. It provides full server functionality, so any EPICS client can communicate with it.

PREFACE: 1st Tensor Polarized Solid Target Workshop

NASA Astrophysics Data System (ADS)

2014-10-01

These are the proceedings of the first Tensor Spin Observables Workshop that was held in March 2014 at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia. The conference was convened to study the physics that can be done with the recently approved E12-13-011 polarized target. A tensor polarized target holds the potential of initiating a new generation of tensor spin physics at Jefferson Lab. Experiments which utilize tensor polarized targets can help clarify how nuclear properties arise from partonic degrees of freedom, provide unique insight into short-range correlations and quark angular momentum, and also help pin down the polarization of the quark sea with a future Electron Ion Collider. This three day workshop was focused on tensor spin observables and the associated tensor target development. The workshop goals were to stimulate progress in the theoretical treatment of polarized spin-1 systems, foster the development of new proposals, and to reach a consensus on the optimal polarized target configuration for the tensor spin program. The workshop was sponsored by the University of New Hampshire, the Jefferson Science Associates, Florida International University, and Jefferson Lab. It was organized by Karl Slifer (chair), Patricia Solvignon, and Elena Long of the University of New Hampshire, Douglas Higinbotham and Christopher Keith of Jefferson Lab, and Misak Sargsian of the Florida International University. These proceedings represent the effort put forth by the community to begin exploring the possibilities that a high-luminosity, high-tensor polarized solid target can offer.

2. GENERAL VIEW, CENTER BUILDING, WITH SIGN SAYING '1855 JEFFERSON ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

2. GENERAL VIEW, CENTER BUILDING, WITH SIGN SAYING '1855 JEFFERSON 1907 INSURANCE BUILDING' Photocopy of April 28, 1915 photograph on file at City Archives of Philadelphia, located at Philadelphia City Hall - Jefferson Fire Insurance Company, 425 Walnut Street, Philadelphia, Philadelphia County, PA

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

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-05

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. PR11-97-000] Jefferson Island Storage & Hub, L.L.C.; Notice of Filing Take notice that on March 28, 2011, Jefferson Island Storage & Hub, L.L.C. (Jefferson Island) submitted a revised Statement of Operating Conditions (SOC) for...

Jefferson's Views on Education: Implications for Today's Social Studies

ERIC Educational Resources Information Center

Carpenter, James J.

2004-01-01

It is virtually impossible to find a U.S. civics or government textbook that does not cite Thomas Jefferson's faith in a well-educated citizenry as the great defense against tyranny. It is also common to open a U.S. history textbook for middle or high school students and find a reference to Jefferson and the value he put on education. Because the…

Transport of LCLS-II 1.3 Ghz cryomodule to SLAC

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGee, M. W.; Arkan, T.; Peterson, T.

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 supportingmore » 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.« less

A MySQL Based EPICS Archiver

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christopher Slominski

2009-10-01

Archiving a large fraction of the EPICS signals within the Jefferson Lab (JLAB) Accelerator control system is vital for postmortem and real-time analysis of the accelerator performance. This analysis is performed on a daily basis by scientists, operators, engineers, technicians, and software developers. Archiving poses unique challenges due to the magnitude of the control system. A MySQL Archiving system (Mya) was developed to scale to the needs of the control system; currently archiving 58,000 EPICS variables, updating at a rate of 11,000 events per second. In addition to the large collection rate, retrieval of the archived data must also bemore » fast and robust. Archived data retrieval clients obtain data at a rate over 100,000 data points per second. Managing the data in a relational database provides a number of benefits. This paper describes an archiving solution that uses an open source database and standard off the shelf hardware to reach high performance archiving needs. Mya has been in production at Jefferson Lab since February of 2007.« less

Targeted Alpha Therapy: The US DOE Tri-Lab (ORNL, BNL, LANL) Research Effort to Provide Accelerator-Produced 225Ac for Radiotherapy

NASA Astrophysics Data System (ADS)

John, Kevin

2017-01-01

Targeted radiotherapy is an emerging discipline of cancer therapy that exploits the biochemical differences between normal cells and cancer cells to selectively deliver a lethal dose of radiation to cancer cells, while leaving healthy cells relatively unperturbed. A broad overview of targeted alpha therapy including isotope production methods, and associated isotope production facility needs, will be provided. A more general overview of the US Department of Energy Isotope Program's Tri-Lab (ORNL, BNL, LANL) Research Effort to Provide Accelerator-Produced 225Ac for Radiotherapy will also be presented focusing on the accelerator-production of 225Ac and final product isolation methodologies for medical applications.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Swapan Chattopadhyay

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 Jeffersonmore » 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

An optimized prototype of electromagnetic calorimeter for the SoLID project at Jefferson Lab

NASA Astrophysics Data System (ADS)

Shen, C.; Wang, Y.; Xiao, D.; Han, D.; Zou, Z.; Li, Y.; Zheng, X.; Chen, J.

2018-02-01

A shashlik-type electromagnetic calorimeter will be produced in Hall A of Jefferson Laboratory for the Solenoidal Large Intensity Device (SoLID). Wavelength-shifting (WLS) fibers and clear fibers will be used as the light guide part of the calorimeter. The blue light from scintillators is converted into green light by WLS fibers and is carried out to the back of the calorimeters for readout. Since the magnetic field of SoLID reaches about 1.5 T behind the calorimeters, the design is to use clear fibers to further guide the light out of the solenoid for readout by PMTs. Therefore, it is important to study the perfomance of WLS and clear fibers. This paper describes a comparative test of two different WLS fibers and a light attenuation test for a clear fiber. The results show that the performance of the two WLS fibers is the same under large curvature bending, and that the bending has no effect on the light transmission through the clear fiber. In addition, a comparison test for two fiber end-face reflective materials is also reported. It reveals that the use of silver ink as a reflective material can increase the light yield by 30%. Thereby, an optimized prototype based on the above experimental results was built and the basic performance was tested.

Plasma density characterization at SPARC_LAB through Stark broadening of Hydrogen spectral lines

NASA Astrophysics Data System (ADS)

Filippi, F.; Anania, M. P.; Bellaveglia, M.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Di Giovenale, D.; Di Pirro, G.; Ferrario, M.; Mostacci, A.; Palumbo, L.; Pompili, R.; Shpakov, V.; Vaccarezza, C.; Villa, F.; Zigler, A.

2016-09-01

Plasma-based acceleration techniques are of great interest for future, compact accelerators due to their high accelerating gradient. Both particle-driven and laser-driven Plasma Wakefield Acceleration experiments are foreseen at the SPARC_LAB Test Facility (INFN National Laboratories of Frascati, Italy), with the aim to accelerate high-brightness electron beams. In order to optimize the efficiency of the acceleration in the plasma and preserve the quality of the accelerated beam, the knowledge of the plasma electron density is mandatory. The Stark broadening of the Hydrogen spectral lines is one of the candidates used to characterize plasma density. The implementation of this diagnostic for plasma-based experiments at SPARC_LAB is presented.

HD gas purification for polarized HDice targets production at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whisnant, Charles; D'Angelo, Annalisa; Colaneri, Luca

2014-06-01

Solid, frozen-spin targets of molecular HD were rst developed for nuclear physics by a collaboration between Syracuse University and Brookhaven National Lab. They have been successfully used in measurements with photon beams, rst at the Laser-Electron-Gamma-Source [1] and most recently at Je erson Lab during the running of the E06-101 (g14) experiment [2]. Preparations are underway to utilize the targets in future electron experiments after the completion of the 12 GeV JLab upgrade [3]. HD is an attractive target since all of the material is polarizable, of low Z, and requires only modest holding elds. At the same time, themore » small contributions from the target cell can be subtracted from direct measurements. Reaching the frozen-spin state with both high polarization and a signi cant spin relaxation time requires careful control of H2 and D2 impurities. Commercially available HD contains 0.5 - 2% concentrations of H2 and D2. Low-temperature distillation is required to reduce these concentrations to the 104 level to enable useful target production. This distillation is done using a column lled with heli-pack C [4] to give good separation e ciency. Approximately 12 moles of commercial HD is condensed into the mechanically refrigerated system at the base temperature of 11K. The system is then isolated and the temperature stabilized at 18K producing liquid HD, which is boiled by a resistive heater. The circulation established by the boil-o condensing throughout the column then ltering back down produces a steady-state isotopic separation permitting the extraction of HD gas with very low H2 and D2 content. A residual gas analyzer initially monitors distillation. Once the H2 concentration falls below its useful operating range, samples are periodically collected for analysis using gas chromatography [5] and Raman scattering. Where the measurement techniques overlap, good agreement is obtained. The operation of the distillery and results of gas analysis will be

Wet Lab Accelerator: A Web-Based Application Democratizing Laboratory Automation for Synthetic Biology.

PubMed

Bates, Maxwell; Berliner, Aaron J; Lachoff, Joe; Jaschke, Paul R; Groban, Eli S

2017-01-20

Wet Lab Accelerator (WLA) is a cloud-based tool that allows a scientist to conduct biology via robotic control without the need for any programming knowledge. A drag and drop interface provides a convenient and user-friendly method of generating biological protocols. Graphically developed protocols are turned into programmatic instruction lists required to conduct experiments at the cloud laboratory Transcriptic. Prior to the development of WLA, biologists were required to write in a programming language called "Autoprotocol" in order to work with Transcriptic. WLA relies on a new abstraction layer we call "Omniprotocol" to convert the graphical experimental description into lower level Autoprotocol language, which then directs robots at Transcriptic. While WLA has only been tested at Transcriptic, the conversion of graphically laid out experimental steps into Autoprotocol is generic, allowing extension of WLA into other cloud laboratories in the future. WLA hopes to democratize biology by bringing automation to general biologists.

Strategic acquisitions by academic medical centers: the Jefferson experience as operational paradigm.

PubMed

Schwartz, G F; Stone, C T

1991-01-01

As capital investments in the health care industry have changed in popularity, mergers and acquisitions of and by hospitals have created supersystems of health care that are based on the assumption that economies of scale offer greater protection from a variety of forces. The acquisition of West Park (Jefferson Park) Hospital by Thomas Jefferson University and the infusion of Jefferson management into Methodist Hospital have provided the institution with unique opportunities to broaden its population base for acute care admissions and to permit greater diversification within the entire health care market.

A PARMELA model of the CEBAF injector valid over a wide range of beam parameters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yuhong Zhang; Kevin Beard; Jay Benesch

A PARMELA model of the CEBAF injector valid over a wide range of beam parameters Yuhong Zhang, Kevin Beard, Jay Benesch, Yu-Chiu Chao, Arne Freyberger, Joseph Grames, Reza Kazimi, Geoff Krafft, Rui Li, Lia Merminga, Matt Poelker, Michael Tiefenback, Byung Yunn Thomas Jefferson National Accelerator Facility 12000 Jefferson Avenue, Newport News, VA 23606 USA An earlier PARMELA model of the Jefferson Lab CEBAF photoinjector was recently revised. The initial phase space distribution of an electron bunch was determined by measuring spot size and pulselength of the driver laser and by beam emittance measurements. The improved model has been used formore » simulations of the simultaneous delivery of the Hall A beam required for a hypernuclear experiment, and the Hall C beam required for the G0 parity violation experiment.« less

Beyond the Schoolhouse Door: Educating the Political Animal in Jefferson's Little Republics

ERIC Educational Resources Information Center

Dotts, Brian W.

2015-01-01

Jefferson believed that citizenship must exhibit republican virtue. While education was necessary in a republican polity, it alone was insufficient in sustaining a revolutionary civic spirit. This paper examines Jefferson's expectations for citizen virtue, specifically related to militia and jury service in his "little republics."…

Lattice Design for a High-Power Infrared FEL

NASA Astrophysics Data System (ADS)

Douglas, D. R.

1997-05-01

A 1 kW infrared FEL, funded by the U.S. Navy, is under construction at Jefferson Lab. This device will be driven by a compact, 42 MeV, 5 mA, energy-recovering, CW SRF-based linear accelerator to produce light in the 3-6.6 μm range. The machine concept comprises a 10 MeV injector, a linac based on a single high-gradient Jefferson Lab accelerator cryomodule, a wiggler and optical cavity, and an energy-recovery recirculation arc. Energy recovery limits cost and technical risk by reducing the RF power requirements in the driver accelerator. Following deceleration to 10 MeV, the beam is dumped. Stringent phase space requirements at the wiggler, low beam energy, and high beam current subject the accelerator lattice to numerous constraints. Principal considerations include: transport and delivery to the FEL of a high-quality, high-current beam; the impact of coherent synchrotron radiation (CSR) during beam recirculation transport; beam optics aberration control, to provide low-loss energy-recovery transport of a 5% relative momentum spread, high-current beam; attention to possible beam breakup (BBU) instabilities in the recirculating accelerator; and longitudinal phase space management during beam transport, to optimize RF drive system control during energy recovery and FEL operation. The presentation will address the design process and design solution for an accelerator transport lattice that meets the requirements imposed by these physical phenomena and operational necessities.

Analysis of the η(548) ->π+π-π0 and η'(958) ->π+π- η channels using a 8-9 GeV tagged photon beam for the GlueX Experiment

NASA Astrophysics Data System (ADS)

Beattie, Tegan; Papandreou, Zisis; Stevens, Justin; GlueX Collaboration

2016-09-01

The primary goal of the GlueX experiment is to conduct a definitive mapping of states in the light meson sector with an emphasis on searching for exotic hybrid mesons as evidence of gluonic excitations. The experiment, housed in the Hall-D facility at Jefferson Lab following its accelerator upgrade to 12 GeV, is now entering the physics data taking phase. The η(548) and η'(958) mesons are two of the richest unflavoured light mesons readily available at GlueX energies for studying resonances. Many other light mesons have decay channels involving the η mesons with significant branching ratios, and πη / πη' resonances are among the top contenders for possibly-accessible exotic and hybrid resonances which GlueX aims to study. As such, the ability to reconstruct pure η/η' samples and analyze their decays is of utmost importance for understanding future work on more complicated analyses. Preliminary analysis results from commissioning data will be presented. This work was supported by NSERC Grant SAPJ-326516 and Jefferson Science Associates, LLC, who operates Jefferson Lab under U.S. DOE Contract No. DE-AC05-06OR23177.

Quench studies of ILC cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eremeev, Grigory; Geng, Rongli; Palczewski, Ari

2011-07-01

Quench limits accelerating gradient in SRF cavities to a gradient lower than theoretically expected for superconducting niobium. Identification of the quenching site with thermometry and OST, optical inspection, and replica of the culprit is an ongoing effort at Jefferson Lab aimed at better understanding of this limiting phenomenon. In this contribution we present our finding with several SRF cavities that were limited by quench.

Thomas Jefferson and the Purposes of Education.

ERIC Educational Resources Information Center

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)

Seventy Five Years of Particle Accelerators

ScienceCinema

Sessler, Andy

2017-12-09

Andy Sessler, Berkeley Lab director from 1973 to 1980, sheds light on the Lab's nearly eight-decade history of inventing and refining particle accelerators, which continue to illuminate the nature of the universe. His talk was presented July 26, 2006.

Metamorphic Mountain, Mount Jefferson State Park: An Environmental Education Learning Experience Designed for Grades 5-7.

ERIC Educational Resources Information Center

Pittman, George K., II; Hubbard, William F.; Lambert, Michael D.; Beazley, Lea J.

Mount Jefferson State Natural Area is located in the southern Blue Ridge highlands of North Carolina and covers 489 acres, which includes peaks and upper slopes to the Mount Jefferson mountain. This document introduces students to the geology of Mount Jefferson State Park and focuses on the geologic processes and rocks and minerals of Mount…

Experiment E89-044 of quasi-elastic diffusion 3He(e,e'p) at Jefferson Laboratory: Analyze cross sections of the two body breakup in parallel kinematics; Experience E89-044 de diffusion quasi-elastique 3he(e,e'p) au Jefferson Laboratory : analyse des sections efficaces de desintegration a deux corps en cinematique parallele (in French)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Penel-Nottaris, Emilie

2004-07-01

The Jefferson Lab Hall A experiment has measured the 3He(e,e'p) reaction cross sections. The separation of the longitudinal and transverse response functions for the two-body breakup reaction in parallel kinematics allows to study the bound proton electromagnetic properties in the 3He nucleus and the involved nuclear mechanisms beyond impulse approximation. Preliminary cross sections show some disagreement with theoretical predictions for the forward angles kinematics around 0 MeV/c missing momenta, and sensitivity to final state interactions and 3He wave functions for missing momenta of 300 MeV/c.

Beam experiments with the Grenoble test electron cyclotron resonance ion source at iThemba LABS.

PubMed

Thomae, R; Conradie, J; Fourie, D; Mira, J; Nemulodi, F; Kuechler, D; Toivanen, V

2016-02-01

At iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) an electron cyclotron ion source was installed and commissioned. This source is a copy of the Grenoble Test Source (GTS) for the production of highly charged ions. The source is similar to the GTS-LHC at CERN and named GTS2. A collaboration between the Accelerators and Beam Physics Group of CERN and the Accelerator and Engineering Department of iThemba LABS was proposed in which the development of high intensity argon and xenon beams is envisaged. In this paper, we present beam experiments with the GTS2 at iThemba LABS, in which the results of continuous wave and afterglow operation of xenon ion beams with oxygen as supporting gases are presented.

Collaborative Lab Reports with Google Docs

NASA Astrophysics Data System (ADS)

Wood, Michael

2011-03-01

Science is a collaborative endeavor. The solitary genius working on the next great scientific breakthrough is a myth not seen much today. Instead, most physicists have worked in a group at one point in their careers, whether as a graduate student, faculty member, staff scientist, or industrial researcher. As an experimental nuclear physicist with research at the Thomas Jefferson National Accelerator Facility, my collaboration consists of over 200 scientists, both national and international. A typical experiment will have a dozen or so principal investigators. Add in the hundreds of staff scientists, engineers, and technicians, and it is clear that science is truly a collaborative effort. This paper will describe the use of Google Docs for collaborative reports for an introductory physics laboratory.

Simultaneous optimization of the cavity heat load and trip rates in linacs using a genetic algorithm

DOE PAGES

Terzić, Balša; Hofler, Alicia S.; Reeves, Cody J.; ...

2014-10-15

In this paper, a genetic algorithm-based optimization is used to simultaneously minimize two competing objectives guiding the operation of the Jefferson Lab's Continuous Electron Beam Accelerator Facility linacs: cavity heat load and radio frequency cavity trip rates. The results represent a significant improvement to the standard linac energy management tool and thereby could lead to a more efficient Continuous Electron Beam Accelerator Facility configuration. This study also serves as a proof of principle of how a genetic algorithm can be used for optimizing other linac-based machines.

Evaluating the Potential of Commercial GIS for Accelerator Configuration Management

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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 buildingmore » 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 centralized framework.« less

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

DTIC Science & Technology

2010-04-14

schools in Mississippi, Samuel decided to send Jefferson to Kentucky when he was old enough to attend school. At the age of eight, he enrolled him at...alone on a steamboat at the age of ten. Back in Mississippi, Davis briefly attended Jefferson College near Natchez before entering Wilkinson Academy...the fields. Davis decided on his own that school had its merits and returned to Wilkinson.9 In 1823 at the age of fifteen Davis enrolled in

Beam experiments with the Grenoble test electron cyclotron resonance ion source at iThemba LABS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thomae, R., E-mail: rthomae@tlabs.ac.za; Conradie, J.; Fourie, D.

2016-02-15

At iThemba Laboratory for Accelerator Based Sciences (iThemba LABS) an electron cyclotron ion source was installed and commissioned. This source is a copy of the Grenoble Test Source (GTS) for the production of highly charged ions. The source is similar to the GTS-LHC at CERN and named GTS2. A collaboration between the Accelerators and Beam Physics Group of CERN and the Accelerator and Engineering Department of iThemba LABS was proposed in which the development of high intensity argon and xenon beams is envisaged. In this paper, we present beam experiments with the GTS2 at iThemba LABS, in which the resultsmore » of continuous wave and afterglow operation of xenon ion beams with oxygen as supporting gases are presented.« less

Ring Imaging Cerenkov Detector for CLAS12

NASA Astrophysics Data System (ADS)

Muhoza, Mireille; Aaron, Elise; Smoot, Waymond; Benmokhtar, Fatiha

2017-09-01

The CLAS12 detector at Thomas Jefferson National Accelerator Facility (TJNAF) is undergoing an upgrade. One of the additions to this detector is a Ring Imaging Cherenkov (RICH) detector to improve particle identification in the 3-8 GeV/c momentum range. Approximately 400 multi anode photomultiplier tubes (MAPMTs) will be used to detect Cherenkov Radiation in the single photoelectron spectra (SPS). Detector tests are taking place at Jefferson Lab, while analysis software development is ongoing at Duquesne. I will be summarizing the work done at Duquesne on the Database development and the analysis of the ADC and TDCs for the Hamamatsu Multi-Anode PMTs that are used for Cerenkov light radiation. National Science Foundation, Award 1615067.

MOUNT JEFFERSON PRIMITIVE AREA, OREGON.

USGS Publications Warehouse

Walker, George W.; Pattee, Eldon C.

1984-01-01

Mineral and reconnaissance geothermal surveys of the Mount Jefferson Primitive Area in the Cascade Range of Oregon indicate little likelihood that metallic or nonmetallic mineral or energy resources exist in the area. Several mining claims, presumably located for gold, are present, but analyses of samples from the claims failed to detect the presence of gold or other valuable metals. Rock for construction purposes is abundantly present, but better and more accessible deposits are available in adjacent areas.

The Economic Impact of Jefferson College on the Community and State--FY1997.

ERIC Educational Resources Information Center

Jefferson Coll., Hillsboro, MO.

This document provides an estimation of the ways in which Jefferson College (Missouri) impacts the economy of Jefferson County and the state as a whole. It offers quantitative information and acts as a reference for the Board of Trustees, administrators, faculty, and staff regarding the economic significance of the college to the area it serves.…

Proceedings of: 2005 Particle Acceleration Confence

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henderson, Stuart

2006-01-01

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 welcomedmore » 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.« less

RadNet Air Data From Jefferson City, MO

EPA Pesticide Factsheets

This page presents radiation air monitoring and air filter analysis data for Jefferson City, MO from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.

Integrated tests of a high speed VXS switch card and 250 MSPS flash ADCs

DOE Office of Scientific and Technical Information (OSTI.GOV)

H. Dong, C. Cuevas, D. Curry, E. Jastrzembski, F. Barbosa, J. Wilson, M. Taylor, B. Raydo

2008-01-01

High trigger rate nuclear physics experiments proposed for the 12 GeV upgrade at the Thomas Jefferson National Accelerator Facility create a need for new high speed digital systems for energy summing. Signals from electronic detectors will be captured with the Jefferson Lab FADC module, which collects and processes data from 16 charged particle sensors with 10 or 12 bit resolution at 250 MHz sample rate. Up to sixteen FADC modules transfer energy information to a central energy summing module for each readout crate. The sums from the crates are combined to form a global energy sum that is used tomore » trigger data readout for all modules. The Energy Sum module and FADC modules have been designed using the VITA-41 VME64 switched serial (VXS) standard. The VITA- 41 standard defines payload and switch slot module functions, and offers an elegant engineered solution for Multi-Gigabit serial transmission on a standard VITA-41 backplane. The Jefferson Lab Energy Sum module receives data serially at a rate of up to 6 Giga-bits per second from the FADC modules. Both FADC and Energy Sum modules have been designed and assembled and this paper describes the integrated tests using both high speed modules in unison« less

75 FR 11916 - Chrysler LLC, Manufacturing Truck and Activity Division, Jefferson North Assembly Plant...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-12

..., Manufacturing Truck and Activity Division, Jefferson North Assembly Plant, Including On-Site Leased Workers From..., Jefferson North Assembly Plant, Detroit, Michigan. The notice was published in the Federal Register on April... substantial portion of which are shipped to an affiliated plant where they are used in the assembly of...

Control Infrastructure for a Pulsed Ion Accelerator

NASA Astrophysics Data System (ADS)

Persaud, A.; Regis, M. J.; Stettler, M. W.; Vytla, V. K.

2016-10-01

We report on updates to the accelerator controls for the Neutralized Drift Compression Experiment II, a pulsed induction-type accelerator for heavy ions. The control infrastructure is built around a LabVIEW interface combined with an Apache Cassandra backend for data archiving. Recent upgrades added the storing and retrieving of device settings into the database, as well as ZeroMQ as a message broker that replaces LabVIEW's shared variables. Converting to ZeroMQ also allows easy access via other programming languages, such as Python.

Control Infrastructure for a Pulsed Ion Accelerator

DOE PAGES

Persaud, A.; Regis, M. J.; Stettler, M. W.; ...

2016-07-27

We report on updates to the accelerator controls for the Neutralized Drift Compression Experiment II, a pulsed induction-type accelerator for heavy ions. The control infrastructure is built around a LabVIEW interface combined with an Apache Cassandra backend for data archiving. Recent upgrades added the storing and retrieving of device settings into the database, as well as ZeroMQ as a message broker that replaces LabVIEW's shared variables. Converting to ZeroMQ also allows easy access via other programming languages, such as Python.

Monitoring vibrations on the Jefferson City Truss Bridge.

DOT National Transportation Integrated Search

2016-05-25

The objective of the research was to determine the frequency and cause of resonant vibrations of truss verticals on bridge A4497 : over the Missouri River in Jefferson City, MO. Instrumentation to monitor the vibrations of four verticals was installe...

MODBUS APPLICATION AT JEFFERSON LAB

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, Jianxun; Seaton, Chad; Philip, Sarin

Modbus is a client/server communication model. In our applications, the embedded Ethernet device XPort is designed as the server and a SoftIOC running EPICS Modbus is the client. The SoftIOC builds a Modbus request from parameter contained in a demand that is sent by the EPICS application to the Modbus Client interface. On reception of the Modbus request, the Modbus server activates a local action to read, write, or achieve some other action. So, the main Modbus server functions are to wait for a Modbus request on 502 TCP port, treat this request, and then build a Modbus response.

Advanced LabVIEW Labs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Eric D.

1999-06-17

In the world of computer-based data acquisition and control, the graphical interface program LabVIEW from National Instruments is so ubiquitous that in many ways it has almost become the laboratory standard. To date, there have been approximately fifteen books concerning LabVIEW, but Professor Essick's treatise takes on a completely different tack than all of the previous discussions. In the more standard treatments of the ways and wherefores of LabVIEW such as LabVIEW Graphical Programming: Practical Applications in Instrumentation and Control by Gary W. Johnson (McGraw Hill, NY 1997), the emphasis has been instructing the reader how to program LabVIEW tomore » create a Virtual Instrument (VI) on the computer for interfacing to a particular instruments. LabVIEW is written in G a graphical programming language developed by National Instruments. In the past the emphasis has been on training the experimenter to learn G . Without going into details here, G incorporates the usual loops, arithmetic expressions, etc., found in many programming languages, but in an icon (graphical) environment. The net result being that LabVIEW contains all of the standard methods needed for interfacing to instruments, data acquisition, data analysis, graphics, and also methodology to incorporate programs written in other languages into LabVIEW. Historically, according to Professor Essick, he developed a series of experiments for an upper division laboratory course for computer-based instrumentation. His observation was that while many students had the necessary background in computer programming languages, there were students who had virtually no concept about writing a computer program let alone a computer- based interfacing program. Thus the beginnings of a concept for not only teaching computer- based instrumentation techniques, but aiso a method for the beginner to experience writing a com- puter program. Professor Essick saw LabVIEW as the perfect environment in which to teach

Advanced LabVIEW Labs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, Eric D.

1999-06-17

In the world of computer-based data acquisition and control, the graphical interface program LabVIEW from National Instruments is so ubiquitous that in many ways it has almost become the laboratory standard. To date, there have been approximately fifteen books concerning LabVIEW, but Professor Essick's treatise takes on a completely different tack than all of the previous discussions. In the more standard treatments of the ways and wherefores of LabVIEW such as LabVIEW Graphical Programming: Practical Applications in Instrumentation and Control by Gary W. Johnson (McGraw Hill, NY 1997), the emphasis has been instructing the reader how to program LabVIEW tomore » create a Virtual Instrument (VI) on the computer for interfacing to a particular instruments. LabVIEW is written in "G" a graphical programming language developed by National Instruments. In the past the emphasis has been on training the experimenter to learn "G". Without going into details here, "G" incorporates the usual loops, arithmetic expressions, etc., found in many programming languages, but in an icon (graphical) environment. The net result being that LabVIEW contains all of the standard methods needed for interfacing to instruments, data acquisition, data analysis, graphics, and also methodology to incorporate programs written in other languages into LabVIEW. Historically, according to Professor Essick, he developed a series of experiments for an upper division laboratory course for computer-based instrumentation. His observation was that while many students had the necessary background in computer programming languages, there were students who had virtually no concept about writing a computer program let alone a computer- based interfacing program. Thus the beginnings of a concept for not only teaching computer- based instrumentation techniques, but aiso a method for the beginner to experience writing a com- puter program. Professor Essick saw LabVIEW as the "perfect environment in which to

Science Requirements and Conceptual Design for a Polarized Medium Energy Electron-Ion Collider at Jlab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abeyratne, S; Ahmed, S; Barber, D

2012-08-01

Researchers have envisioned an electron-ion collider with ion species up to heavy ions, high polarization of electrons and light ions, and a well-matched center-of-mass energy range as an ideal gluon microscope to explore new frontiers of nuclear science. In its most recent Long Range Plan, the Nuclear Science Advisory Committee (NSAC) of the US Department of Energy and the National Science Foundation endorsed such a collider in the form of a 'half-recommendation.' As a response to this science need, Jefferson Lab and its user community have been engaged in feasibility studies of a medium energy polarized electron-ion collider (MEIC), cost-effectivelymore » utilizing Jefferson Lab's already existing Continuous Electron Beam Accelerator Facility (CEBAF). In close collaboration, this community of nuclear physicists and accelerator scientists has rigorously explored the science case and design concept for this envisioned grand instrument of science. An electron-ion collider embodies the vision of reaching the next frontier in Quantum Chromodynamics - understanding the behavior of hadrons as complex bound states of quarks and gluons. Whereas the 12 GeV Upgrade of CEBAF will map the valence-quark components of the nucleon and nuclear wave functions in detail, an electron-ion collider will determine the largely unknown role sea quarks play and for the first time study the glue that binds all atomic nuclei. The MEIC will allow nuclear scientists to map the spin and spatial structure of quarks and gluons in nucleons, to discover the collective effects of gluons in nuclei, and to understand the emergence of hadrons from quarks and gluons. The proposed electron-ion collider at Jefferson Lab will collide a highly polarized electron beam originating from the CEBAF recirculating superconducting radiofrequency (SRF) linear accelerator (linac) with highly polarized light-ion beams or unpolarized light- to heavy-ion beams from a new ion accelerator and storage complex. Since the

The Economic Impact of Jefferson College on the Community and the State, FY 2002.

ERIC Educational Resources Information Center

Jefferson Coll., Hillsboro, MO.

The purpose of this study is to provide an estimation of the ways in which Jefferson College impacts and stimulates the economy of Jefferson County and the state of Missouri as a whole. It provides quantitative information for use by the Board of Trustees and the Administrative Cabinet in institutional planning endeavors. It is also a useful…

Reflections on Three Corporate Research Labs: Bell Labs, HP Labs, Agilent Labs

NASA Astrophysics Data System (ADS)

Hollenhorst, James

2008-03-01

This will be a personal reflection on corporate life and physics-based research in three industrial research labs over three decades, Bell Labs during the 1980's, HP Labs during the 1990's, and Agilent Labs during the 2000's. These were times of great change in all three companies. I'll point out some of the similarities and differences in corporate cultures and how this impacted the research and development activities. Along the way I'll mention some of the great products that resulted from physics-based R&D.

A Proposed Incentive System for Jefferson County Teachers.

ERIC Educational Resources Information Center

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)

A study of 3π production in γp → n -π +π +π - and γ-p → Δ + +π +π -π - with CLAS at Jefferson Lab ->n

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tsaris, Aristedis

2016-02-22

Apart from the mesons that the constituent quark model predicts, QCD allows for additional states beyond the qq system. Previous experiments have performed partial wave analysis on pion-production data and claim observation of an exotic J PC = 1 -+ state decaying via p-π. The g12 experiment took place at Jefferson Lab using the CLAS spectrometer, a liquid hydrogen target was used and a tagged photon beam. By studying the reactions γp → n -π +π +π - and γp → Δ + +π +π -π -, the photoproduction of mesons decaying to 3-pi was studied using two different butmore » complimentary channels. Events are selected with low four-momentum transfer to the baryon, in order to enhance one pion exchange production. For both 3-pi systems the data exhibit two intermediate decays, p-pi and f 2π. For the γp → n -π +π +π - reaction over 600k events were acquired resulting in the largest 3 photoproduction dataset to date. The exotic J PC = 1 -+ partial wave does not show resonant behavior and more so it is strongly consistent with a non-resonant non-interfering wave relative to a resonant π 2(1670). Furthermore, the partial wave analysis shows production of the a 2(1320) and π 2(1670) mesons. For the first time we report observation of a photoproduced a 1(1260) meson. For the γp → Δ + +π +π -π - reaction nearly 350k events were analyzed. A partial wave analysis was performed for the first time on this channel. The a1(1260), a2(1320), and the 2(1670) mesons were observed. Observation of the a1(1260) confirms the result first reported in γp → n -π +π +π - reaction.« less

Compensation Techniques in Accelerator Physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sayed, Hisham Kamal

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. Twomore » 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.« less

Changing Course in Jefferson City: Reevaluating a District Initiative to Convert Under-Enrolled Elementary Schools

ERIC Educational Resources Information Center

Lochmiller, Chad R.

2018-01-01

This case positions the reader as the superintendent of Jefferson City Public Schools (pseudonym). Like many urban school districts in the United States, Jefferson City faces a complex milieu of fiscal challenges attributed to inadequate state funding and declining student enrollment. Within this case, the superintendent must address the failing…

ATOM - Accelerating Therapeutics for Opportunities in Medicine | FNLCR Staging

Cancer.gov

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

Status of the LCLS-II Accelerating Cavity Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Daly, Ed; Marhauser, Frank; Fitzpatrick, Jarrod A.

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.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Derbenev, Yaroslav S.; Morozov, Vasiliy; Lin, Fanglei

We present a complete scheme for managing the polarization of ion beams in Jefferson Lab's proposed Medium-energy Electron-Ion Collider (MEIC). It provides preservation of the ion polarization during all stages of beam acceleration and polarization control in the collider's experimental straights. We discuss characteristic features of the spin motion in accelerators with Siberian snakes and in accelerators of figure-8 shape. We propose 3D spin rotators for polarization control in the MEIC ion collider ring. We provide polarization calculations in the collider with the 3D rotator for deuteron and proton beams. The main polarization control features of the figure-8 design aremore » summarized.« less

Accelerated Testing and Analysis | Photovoltaic Research | NREL

Science.gov Websites

& Engineering pages: Real-Time PV & Solar Resource Testing Systems Engineering Systems PV standards. Each year, NCPV researchers, along with solar companies and other national lab Accelerated Testing and Analysis Accelerated Testing and Analysis PV Research Other Reliability

Quench Studies of Six High Temperature Nitrogen Doped 9 Cell Cavities for Use in the LCLS-II Baseline Prototype Cryomodule at Jefferson Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Palczewski, Ari; Geng, Rongli; Eremeev, Grigory

Jefferson Lab (JLab) processed six nine-cell cavities as part of a small-scale production for LCLS-II cavity processing development utilizing the promising nitrogen-doping process. Various nitrogen-doping recipes have been scrutinized to optimize process parameters with the aim to guarantee an unloaded quality factor (Q_0) of 2.7∙10 10 at an accelerating field (Eacc) of 16 MV/m at 2.0 K in the cryomodule. During the R&D phase the characteristic Q0 vs. Eacc performance curve of the cavities has been measured in JLab’s vertical test area at 2 K. The findings showed the characteristic rise of the Q0 with Eacc as expected from nitrogen-doping.more » Initially, five cavities achieved an average Q0 of 3.3·10 10 at the limiting Eacc averaging to 16.8 MV/m, while one cavity experienced an early quench accompanied by an unusual Q_0 vs. Eacc curve. The project accounts for a cavity performance loss from the vertical dewar test (with or without the helium vessel) to the horizontal performance in a cryomodule, such that these results leave no save margin to the cryomodule specification. Consequently, a refinement of the nitrogen-doping has been initiated to guarantee an average quench field above 20 MV/m without impeding the Q_0. This paper covers the refinement work performed for each cavity, which depends on the initial results, as well as a quench analysis carried out before and after the rework during the vertical RF tests as far as applicable.« less

Research and Development for an Alternative RF Source Using Magnetrons in CEBAF

NASA Astrophysics Data System (ADS)

Jacobs, Andrew

2016-09-01

At Jefferson Lab, klystrons are currently used as a radiofrequency (RF) power source for the 1497 MHz Continuous Electron Beam Accelerator Facility (CEBAF) Continuous Wave (CW) system. A drop-in replacement for the klystrons in the form of a system of magnetrons is being developed. The klystron DC-RF efficiency at CEBAF is 35-51% while the estimated magnetron efficiency is 80-90%. Thus, the introduction of magnetrons to CEBAF will have enormous benefits in terms of electrical power saving. The primary focus of this project was to characterize a magnetron's frequency pushing and pulling curves at 2.45 GHz with stub tuner and anode current adjustments so that a Low Level RF controller for a new 1.497 GHz magnetron can be built. A Virtual Instrument was created in LabVIEW, and data was taken. The resulting data allowed for the creation of many constant lines of frequency and output power. Additionally, the results provided a characterization of magnetron oven temperature drift over the operation time and the relationship between anode current and frequency. Using these results, the control model of different variables and their feedback or feedforward that affect the frequency pushing and pulling of the magnetron is better developed. Department of Energy, Science Undergraduate Laboratory Internships, and Jefferson Lab.

Lab experiments are a major source of knowledge in the social sciences.

PubMed

Falk, Armin; Heckman, James J

2009-10-23

Laboratory experiments are a widely used methodology for advancing causal knowledge in the physical and life sciences. With the exception of psychology, the adoption of laboratory experiments has been much slower in the social sciences, although during the past two decades the use of lab experiments has accelerated. Nonetheless, there remains considerable resistance among social scientists who argue that lab experiments lack "realism" and generalizability. In this article, we discuss the advantages and limitations of laboratory social science experiments by comparing them to research based on nonexperimental data and to field experiments. We argue that many recent objections against lab experiments are misguided and that even more lab experiments should be conducted.

Seventy Five Years of Particle Accelerators (LBNL Summer Lecture Series)

ScienceCinema

Sessler, Andy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-12-09

Summer Lecture Series 2006: Andy Sessler, Berkeley Lab director from 1973 to 1980, sheds light on the Lab's nearly eight-decade history of inventing and refining particle accelerators, which continue to illuminate the nature of the universe.

Thomas Jefferson's Plan for the University of Virginia: Lessons from the Lawn. Teaching with Historic Places.

ERIC Educational Resources Information Center

Hughes, Mary; Wilson, Sara

This lesson is based on the National Register of Historic Places registration file, "University of Virginia Historic District," and other primary and secondary materials about Thomas Jefferson and the ctreation of the University of Virginia. Thomas Jefferson did not begin the effort of designing the University of Virginia…

Operational experience on the generation and control of high brightness electron bunch trains at SPARC-LAB

NASA Astrophysics Data System (ADS)

Mostacci, A.; Alesini, D.; Anania, M. P.; Bacci, A.; Bellaveglia, M.; Biagioni, A.; Cardelli, F.; Castellano, Michele; Chiadroni, Enrica; Cianchi, Alessandro; Croia, M.; Di Giovenale, Domenico; Di Pirro, Giampiero; Ferrario, Massimo; Filippi, Francesco; Gallo, Alessandro; Gatti, Giancarlo; Giribono, Anna; Innocenti, L.; Marocchino, A.; Petrarca, M.; Piersanti, L.; Pioli, S.; Pompili, Riccardo; Romeo, Stefano; Rossi, Andrea Renato; Shpakov, V.; Scifo, J.; Vaccarezza, Cristina; Villa, Fabio; Weiwei, L.

2015-05-01

Sub-picosecond, high-brightness electron bunch trains are routinely produced at SPARC-LAB via the velocity bunching technique. Such bunch trains can be used to drive multi-color Free Electron Lasers (FELs) and plasma wake field accelerators. In this paper we present recent results at SPARC-LAB on the generation of such beams, highlighting the key points of our scheme. We will discuss also the on-going machine upgrades to allow driving FELs with plasma accelerated beams or with short electron pulses at an increased energy.

77 FR 74784 - Safety Zone for Recovery Operations for East Jefferson Street Train Derailment, Mantua Creek...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-18

... 1625-AA00 Safety Zone for Recovery Operations for East Jefferson Street Train Derailment, Mantua Creek... establishing a safety zone one mile north and one mile south of the East Jefferson Street Railroad Bridge... materials into Mantua Creek and the surrounding air. This regulation is necessary to provide for the safety...

Transforming Our Schools: Lessons from the Jefferson County Public Schools/Gheens Professional Development Academy, 1983-1991.

ERIC Educational Resources Information Center

Kyle, Regina M. J.

A school/community partnership in Louisville, Kentucky, the Jefferson County Public Schools/Gheens Professional Development Academy, is described. This report provides a framework for assessing Jefferson County School System reforms in the past 8 years or more designed to enhance student success in learning. A Spiral of Assessment was used to…

SHMS Hodoscopes and Time of Flight System

NASA Astrophysics Data System (ADS)

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.

Metamorphic Mountain: Mount Jefferson State Park. An Environmental Education Learning Experience Designed for Grades 5-7.

ERIC Educational Resources Information Center

Pittman, George K., II

This activity packet was designed to introduce students in grades 5-7 to the geology of the Blue Ridge Mountains through hands-on activities for the classroom and the outdoor setting of Mount Jefferson State Park (Jefferson, North Carolina). Previsit activities introduce students to the different rock types: sedimentary, igneous, and metamorphic.…

Brazilian version of the Jefferson Scale of Empathy: psychometric properties and factor analysis

PubMed Central

2012-01-01

Background Empathy is a central characteristic of medical professionalism and has recently gained attention in medical education research. The Jefferson Scale of Empathy is the most commonly used measure of empathy worldwide, and to date it has been translated in 39 languages. This study aimed to adapt the Jefferson Scale of Empathy to the Brazilian culture and to test its reliability and validity among Brazilian medical students. Methods The Portuguese version of the Jefferson Scale of Empathy was adapted to Brazil using back-translation techniques. This version was pretested among 39 fifth-year medical students in September 2010. During the final fifth- and sixth-year Objective Structured Clinical Examination (October 2011), 319 students were invited to respond to the scale anonymously. Cronbach’s alpha, exploratory factor analysis, item-total correlation, and gender comparisons were performed to check the reliability and validity of the scale. Results The student response rate was 93.7% (299 students). Cronbach’s coefficient for the scale was 0.84. A principal component analysis confirmed the construct validity of the scale for three main factors: Compassionate Care (first factor), Ability to Stand in the Patient’s Shoes (second factor), and Perspective Taking (third factor). Gender comparisons did not reveal differences in the scores between female and male students. Conclusions The adapted Brazilian version of the Jefferson Scale of Empathy proved to be a valid, reliable instrument for use in national and cross-cultural studies in medical education. PMID:22873730

Lab experiments investigating astrophysical jet physics

NASA Astrophysics Data System (ADS)

Bellan, Paul

2014-10-01

Dynamics relevant to astrophysical plasmas is being investigated in lab experiments having similar physics and topology, but much smaller time and space scales. High speed movies and numerical simulations both show that highly collimated MHD-driven plasma flows are a critical feature; these collimated flows can be considered to be a lab version of an astrophysical jet. Having both axial and azimuthal magnetic fields, the jet is effectively an axially lengthening plasma-confining flux tube with embedded helical magnetic field (flux rope). The jet velocity is in good agreement with an MHD acceleration model. Axial stagnation of the jet compresses embedded azimuthal magnetic flux and so results in jet self-collimation. Jets kink when they breach the Kruskal-Shafranov stability limit. The lateral acceleration of a sufficiently strong kink can provide an effective gravity which provides the environment for a spontaneously-developing, fine-scale, extremely fast Rayleigh-Taylor instability that erodes the current channel to be smaller than the ion skin depth. This cascade from the ideal MHD scale of the kink to the non-MHD ion skin depth scale can result in a fast magnetic reconnection whereby the jet breaks off from its source electrode. Supported by USDOE and NSF.

Foreign Language Camps: Jefferson County Public Schools R-1.

ERIC Educational Resources Information Center

Trujillo, Lorenzo A.; And Others

The planning and operation of Jefferson County (Colorado) Public Schools' foreign language camps are described. The weekend-long camps attempt to duplicate an authentic cultural experience in a foreign village through cultural activities and language immersion. French, Spanish, Russian, and German camps are conducted for county high school foreign…

Gateway Arch Circulator Conceptual Feasibility Study : Jefferson National Expansion Memorial

DOT National Transportation Integrated Search

2015-03-01

The Jefferson National Expansion Memorial (JEFF) is undergoing major design changes as part of the City Arch River 2015 project (CAR) that will impact access for park visitors. The park and stakeholders are considering a circulator system to facilita...

High energy polarimetry of positron beams

DOE PAGES

Gaskell, D.

2018-05-01

Møller and Compton polarimetry are the primary techniques used for high energy electron polarimetry at Jefferson Lab. Both techniques can also be used for positron polarimetry, in principle. However, some modifications to the configuration and/or operating mode of the existing devices will likely be required for use with the types of positron beams currently under consideration at Jefferson Lab.

High energy polarimetry of positron beams

NASA Astrophysics Data System (ADS)

Gaskell, D.

2018-05-01

Møller and Compton polarimetry are the primary techniques used for high energy electron polarimetry at Jefferson Lab. In principle, both techniques can also be used for positron polarimetry. However, some modifications to the configuration and/or operating mode of the existing devices will likely be required for use with the types of positron beams currently under consideration at Jefferson Lab.

Structural Analysis of Thermal Shields During a Quench of a Torus Magnet for the 12 GeV Upgrade

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pastor, Orlando; Willard, Thomas; Ghoshal, Probir K.

A toroidal magnet system consisting of six superconducting coils is being built for the Jefferson Lab 12- GeV accelerator upgrade project. This paper details the analysis of eddy current effects during a quench event on the aluminum thermal shield. The shield has been analyzed for mechanical stresses induced as a result of a coil quench as well as a fast discharge of the complete magnet system. The shield has been designed to reduce the eddy current effects and result in stresses within allowable limits.

Recent optimization of the beam-optical characteristics of the 6 MV van de Graaff accelerator for high brightness beams at the iThemba LABS NMP facility

NASA Astrophysics Data System (ADS)

Conradie, J. L.; Eisa, M. E. M.; Celliers, P. J.; Delsink, J. L. G.; Fourie, D. T.; de Villiers, J. G.; Maine, P. M.; Springhorn, K. A.; Pineda-Vargas, C. A.

2005-04-01

With the aim of improving the reliability and stability of the beams delivered to the nuclear microprobe at iThemba LABS, as well as optimization of the beam characteristics along the van de Graaff accelerator beamlines in general, relevant modifications were implemented since the beginning of 2003. The design and layout of the beamlines were revised. The beam-optical characteristics through the accelerator, from the ion source up to the analysing magnet directly after the accelerator, were calculated and the design optimised, using the computer codes TRANSPORT, IGUN and TOSCA. The ion source characteristics and optimal operating conditions were determined on an ion source test bench. The measured optimal emittance for 90% of the beam intensity was about 50π mm mrad for an extraction voltage of 6 kV. These changes allow operation of the Nuclear Microprobe at proton energies in the range 1 MeV-4 MeV with beam intensities of tenths of a pA at the target surface. The capabilities of the nuclear microprobe facility were evaluated in the improved beamline, with particular emphasis to bio-medical samples.

Ornamental Planting Restoration at Jefferson's Poplar Forest Through XRF and ICP-OES Analysis of Disturbed Soils

NASA Astrophysics Data System (ADS)

Hatfield, M.; Low, P. C.; Devlin, S.

2011-12-01

Thomas Jefferson's Poplar Forest estate near Lynchburg, VA is currently attempting to restore the property to its Jeffersonian condition. Subsequent modifications to the property following its sale by Jefferson's heirs included the removal of the original trees in order to facilitate agricultural activity. One key facet of the restoration involves determining the precise location of the sixty-four paper mulberry trees that Jefferson reportedly had transplanted in 1815 from his on-site nursery to near the main house. At Monticello, it is well-documented that Jefferson used contextually innovative fertilizing techniques, including the addition of gypsum and lime "to restore the exhaustion of a single crop from the soil." Whether he used these methods in the nursery at Poplar Forest to the degree that decades of subsequent leaching, weathering, and other disturbances would not erase remains historically and analytically unclear. Since the transplantation process requires that large amounts of soil be moved with the trees, small areas of compositionally distinct soils in the suspected planting area could be used to establish the exact location of each tree through differentiating between nursery and in situ soils. Through X-ray fluorescence spectroscopy (XRF) and intercoupled plasma optical emission spectroscopy (ICP-OES) geochemical analysis, the specific composition of soil can be determined. Preliminary analysis shows slight differences in phosphorus and sulfur between the nursery and in situ soil; however, the property lies on three different distinct geological units: actinolite schist and feldspathic metagreywacke units of the Alligator Back formation, and biotite gneiss of the Ashe Formation (biotite gneiss). The location of the nursery where the sixty-four paper mulberry trees were originally grown lies on the feldspathic metagreywacke unit; whereas the relocation site where Jefferson had them planted rests on the actinolite schist unit. Percursory study

75 FR 16700 - Special Local Regulation, Swim Across the Sound, Long Island Sound, Port Jefferson, NY to Captain...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-04-02

...-AA08 Special Local Regulation, Swim Across the Sound, Long Island Sound, Port Jefferson, NY to Captain... permanent Special Local Regulation on the navigable waters of Long Island Sound between Port Jefferson, NY and Captain's Cove Seaport, Bridgeport, CT due to the annual Swim Across the Sound event. The proposed...

Innovative single-shot diagnostics for electrons from laser wakefield acceleration at FLAME

NASA Astrophysics Data System (ADS)

Bisesto, F. G.; Anania, M. P.; Cianchi, A.; Chiadroni, E.; Curcio, A.; Ferrario, M.; Pompili, R.; Zigler, A.

2017-07-01

Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (> 100 GV/m), enabling acceleration of electrons to GeV energy in few centimeters. Here we present all the plasma related activities currently underway at SPARC_LAB exploiting the high power laser FLAME. In particular, we will give an overview of the single shot diagnostics employed: Electro Optic Sampling (EOS) for temporal measurement and Optical Transition Radiation (OTR) for an innovative one shot emittance measurements. In detail, the EOS technique has been employed to measure for the first time the longitudinal profile of electric field of fast electrons escaping from a solid target, driving the ions and protons acceleration, and to study the impact of using different target shapes. Moreover, a novel scheme for one shot emittance measurements based on OTR, developed and tested at SPARC_LAB LINAC, used in an experiment on electrons from laser wakefield acceleration still undergoing, will be shown.

The Jefferson Science Fellows (JSF) program at the US Department of State

NASA Astrophysics Data System (ADS)

Peterson, Roy

2014-09-01

In 2004 the US Department of State and the National Academies established the Jefferson Science Fellows program, to bring tenured faculty in sciences, engineering, and medicine to the Department of State or USAID for a year in residence, with continuing connections. Over twenty physical scientists have been Fellows, working in a wide variety of offices on a broad range of topics. The main advantage to Fellows is the opportunity to make an impact on important national and international issues, applying skills and judgments gained through their research, teaching, and service. The JSF experience can also create broader horizons for physicists, especially beyond the laboratory. The selection process and examples, including my own, will be described. Information can be found at //sites.nationalacademies.org/PGA/Jefferson/.

33 CFR 100.121 - Swim Across the Sound, Long Island Sound, Port Jefferson, NY to Captain's Cove Seaport...

Code of Federal Regulations, 2011 CFR

2011-07-01

... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Swim Across the Sound, Long Island Sound, Port Jefferson, NY to Captain's Cove Seaport, Bridgeport, CT. 100.121 Section 100.121... SAFETY OF LIFE ON NAVIGABLE WATERS § 100.121 Swim Across the Sound, Long Island Sound, Port Jefferson, NY...

250 Years of Physics at the College of William and Mary: 1760-2010

NASA Astrophysics Data System (ADS)

von Baeyer, Hans

2010-02-01

The recorded history of physics at William and Mary begins when Thomas Jefferson, the College's most distinguished alumnus, meets his mentor, Dr. William Small of Scotland, who opens his eyes to the wonders of natural philosophy. After the vicissitudes of the Revolution and the Civil War, physics enjoys a revival in the twentieth century, culminating in the creation of a Ph.D. program in the 1960s and the building of the William Small Physical Laboratory in Williamsburg. In the 1980s the modern era is launched by the establishment of the US Department of Energy's Jefferson Lab for nuclear physics in nearby Newport News. Today both Small Hall and Jefferson Lab are in the process of renovation. The legacies of Small and Jefferson for physics at William and Mary are secure! )

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

PubMed

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.

Measurement of the E Polarization Observable for yd --> pi^-p(p_s), yd-->K^0Lambda(p_s), and yd-->pi^+pi^-d(0) using CLAS g14 data at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ho, Dao

Photoproduction of mesons from the nucleon has a long and ongoing tradition for exploring nucleon excitations and the baryon-baryon interaction. Polarization observables which play a role in the photoproduction mechanism are, therefore, essential in addition to the differential cross section. The CLAS collaboration at Jefferson Lab, has been active in measuring these observables, but until now only on a proton targets. However, a comprehensive picture of the pseudoscalar meson photoproduction requires neutron data as well. That is, paired measurements of observables in p and n reactions are necessary to disentangle the photoproduction mechanism on the basis of isospin I =more » 0, and I = 1 photo-coupling transition amplitudes. The g14 experiment with 'HDIce,' a longitudinally polarized solid target of molecular hydrogen-deuteride with low background contamination from other nuclear species, provided an unique opportunity to measure several polarization observables|for the first time|on the neutron for different channels. In particular, we present our measurements of the E beam-target polarization observable, which requires circularly polarized beam and a longitudinally polarized target, for p pi^-, K^0Lambda, and K^0Sigma^0 channels in the energy range of 1.5 lte W lte 2.3 GeV. In addition, we also utilized the g14 dataset to investigate the intrinsic spin of a possible dibaryonic ND bound state by measuring the E (beam-target) observable on the d-pi^+/-d channel of the reaction yd --> pi^+pi^-d(0). Finally, this thesis also discusses a highly efficient multivariate analysis method called Boosted Decision Trees, which we employed extensively for this work and which has not been used before in CLAS data analysis.« less

GeoLab's First Field Trials, 2010 Desert RATS: Evaluating Tools for Early Sample Characterization

NASA Technical Reports Server (NTRS)

Evans, Cindy A.; Bell, M. S.; Calaway, M. J.; Graff, Trevor; Young, Kelsey

2011-01-01

As part of an accelerated prototyping project to support science operations tests for future exploration missions, we designed and built a geological laboratory, GeoLab, that was integrated into NASA's first generation Habitat Demonstration Unit-1/Pressurized Excursion Module (HDU1-PEM). GeoLab includes a pressurized glovebox for transferring and handling samples collected on geological traverses, and a suite of instruments for collecting preliminary data to help characterize those samples. The GeoLab and the HDU1-PEM were tested for the first time as part of the 2010 Desert Research and Technology Studies (DRATS), NASA's analog field exercise for testing mission technologies. The HDU1- PEM and GeoLab participated in two weeks of joint operations in northern Arizona with two crewed rovers and the DRATS science team.

Oryza rufipogon introgressions improve yield in the U.S. cultivar Jefferson

USDA-ARS?s Scientific Manuscript database

An advanced backcross (BC2) population was developed to explore the breeding value of the wild ancestral species O. rufipogon (IRGC 105491) in a cross with the tropical japonica US variety, cv Jefferson. Early generation selection eliminated lines which possessed undesirable traits such as dormancy,...

Love the Lab, Hate the Lab Report?

ERIC Educational Resources Information Center

Bjorn, Genevive

2018-01-01

In the author's large, urban high school, enrollment in a laboratory science is mandatory. While the student participation rate for lab activities is over 98%, the turn-in rate for traditional lab reports averages just 35% to 85%. Those students who don't produce a lab report miss a critical opportunity to improve their skills in scientific…

Accelerators for America's Future

NASA Astrophysics Data System (ADS)

Bai, Mei

2016-03-01

Particle accelerator, a powerful tool to energize beams of charged particles to a desired speed and energy, has been the working horse for investigating the fundamental structure of matter and fundermental laws of nature. Most known examples are the 2-mile long Stanford Linear Accelerator at SLAC, the high energy proton and anti-proton collider Tevatron at FermiLab, and Large Hadron Collider that is currently under operation at CERN. During the less than a century development of accelerator science and technology that led to a dazzling list of discoveries, particle accelerators have also found various applications beyond particle and nuclear physics research, and become an indispensible part of the economy. Today, one can find a particle accelerator at almost every corner of our lives, ranging from the x-ray machine at the airport security to radiation diagnostic and therapy in hospitals. This presentation will give a brief introduction of the applications of this powerful tool in fundermental research as well as in industry. Challenges in accelerator science and technology will also be briefly presented

Innovative single-shot diagnostics for electrons accelerated through laser-plasma interaction at FLAME

NASA Astrophysics Data System (ADS)

Bisesto, F. G.; Anania, M. P.; Chiadroni, E.; Cianchi, A.; Costa, G.; Curcio, A.; Ferrario, M.; Galletti, M.; Pompili, R.; Schleifer, E.; Zigler, A.

2017-05-01

Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (> 100 GV/m), enabling acceleration of electrons to GeV energy in few centimeters. Here we present all the plasma related activities currently underway at SPARC LAB exploiting the high power laser FLAME. In particular, we will give an overview of the single shot diagnostics employed: Electro Optic Sampling (EOS) for temporal measurement and optical transition radiation (OTR) for an innovative one shot emittance measurements. In detail, the EOS technique has been employed to measure for the first time the longitudinal profile of electric field of fast electrons escaping from a solid target, driving the ions and protons acceleration, and to study the impact of using different target shapes. Moreover, a novel scheme for one shot emittance measurements based on OTR, developed and tested at SPARC LAB LINAC, will be shown.

A versatile scalable PET processing system

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

2011-06-01

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 tomore » 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.« less

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

PubMed

Williams, Brett; Sifris, Adiva; Lynch, Marty

2016-01-01

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. 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. 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. 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.

Femtosecond timing distribution and control for next generation accelerators and light sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Li -Jin

Femtosecond Timing Distribution At LCLS Free-electron-lasers (FEL) have the capability of producing high photon flux from the IR to the hard x-ray wavelength range and to emit femtosecond and eventually even attosecond pulses. This makes them an ideal tool for fundamental as well as applied re-search. Timing precision at the Stanford Linear Coherent Light Source (LCLS) between the x-ray FEL (XFEL) and ultrafast optical lasers is currently no better than 100 fs RMS. Ideally this precision should be much better and could be limited only by the x-ray pulse duration, which can be as short as a few femtoseconds. Anmore » increasing variety of science problems involving electron and nuclear dynamics in chemical and material systems will become accessible as the timing improves to a few femtoseconds. Advanced methods of electron beam conditioning or pulse injection could allow the FEL to achieve pulse durations less than one femtosecond. The objective of the work described in this proposal is to set up an optical timing distribution system based on mode locked Erbium doped fiber lasers at LCLS facility to improve the timing precision in the facility and allow time stamping with a 10 fs precision. The primary commercial applications for optical timing distributions systems are seen in the worldwide accelerator facilities and next generation light sources community. It is reasonable to expect that at least three major XFELs will be built in the next decade. In addition there will be up to 10 smaller machines, such as FERMI in Italy and Maxlab in Sweden, plus the market for upgrading already existing facilities like Jefferson Lab. The total market is estimated to be on the order of a 100 Million US Dollars. The company owns the exclusive rights to the IP covering the technology enabling sub-10 fs synchronization systems. Testing this technology, which has set records in a lab environment, at LCLS, hence in a real world scenario, is an important corner stone of bringing the

Water resources of Jefferson Davis Parish, Louisiana

USGS Publications Warehouse

White, Vincent E.; Prakken, Lawrence B.

2014-01-01

Information concerning the availability, use, and quality of water in Jefferson Davis Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the availability, past and current use, use trends, and water quality from groundwater and surface-water sources in the parish is presented. Previously published reports and data stored in the U.S. Geological Survey’s National Water Information System (http://waterdata.usgs.gov/nwis) are the primary sources of the information presented here.

75 FR 80524 - Watercress Darter National Wildlife Refuge, Jefferson County, AL

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-22

... Darter NWR, near the city of Bessemer, Jefferson County, Alabama, was established by the Service in 1980... occur in the city of Bessemer, Alabama. Watercress Darter NWR is a small system that can be greatly..., watershed, and biota exchange pathways. Extensive resource sharing and networking with other protected areas...

DOE EiR at Oakridge National Lab 2008/09

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bauer, Michael

2012-11-30

This project placed an experienced technology entrepreneur at Oak Ridge National Lab, one of DOE's premier laboratories undertaking cutting edge research in a variety of fields, including energy technologies. With the goal of accelerating the commercialization of advanced energy technologies, the task was to review available technologies at the lab and identify those that qualify for licensing and commercialization by a private startup company, backed by private venture capital. During the project, more than 1,500 inventions filed at the lab were reviewed over a 1 year period; a successively smaller number was selected for more detailed review, ultimately resulting inmore » five, and then 1 technology, being reviewed for immediate commercialization. The chosen technology, consisting in computational chemistry based approached to optimization of enzymes, was tested in lab experiments, paid for by funds raised by ORNL for the purpose of proving out the effectiveness of the technology and readiness for commercialization. The experiments proved out that the technology worked however it's performance proved not yet mature enough to qualify for private venture capital funded commercialization in a high tech startup. As a consequence, the project did not result in a new startup company being formed, as originally intended.« less

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

C. K. Sinclair; P. A. Adderley; B. M. Dunham

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 havemore » 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.« less

Industrialization of the nitrogen-doping preparation for SRF cavities for LCLS-II

NASA Astrophysics Data System (ADS)

Gonnella, D.; Aderhold, S.; Burrill, A.; Daly, E.; Davis, K.; Grassellino, A.; Grimm, C.; Khabiboulline, T.; Marhauser, F.; Melnychuk, O.; Palczewski, A.; Posen, S.; Ross, M.; Sergatskov, D.; Sukhanov, A.; Trenikhina, Y.; Wilson, K. M.

2018-03-01

The Linac Coherent Light Source II (LCLS-II) is a new state-of-the-art coherent X-ray source being constructed at SLAC National Accelerator Laboratory. It employs 280 superconducting radio frequency (SRF) cavities in order operate in continuous wave (CW) mode. To reduce the overall cryogenic cost of such a large accelerator, nitrogen-doping of the SRF cavities is being used. Nitrogen-doping has consistently been shown to increase the efficiency of SRF cavities operating in the 2.0 K regime and at medium fields (15-20 MV/m) in vertical cavity tests and horizontal cryomodule tests. While nitrogen-doping's efficacy for improvement of cavity performance was demonstrated at three independent labs, Fermilab, Jefferson Lab, and Cornell University, transfer of the technology to industry for LCLS-II production was not without challenges. Here we present results from the beginning of LCLS-II cavity production. We discuss qualification of the cavity vendors and the first cavities from each vendor. Finally, we demonstrate that nitrogen-doping has been successfully transferred to SRF cavity vendors, resulting in consistent production of cavities with better cryogenic efficiency than has ever been achieved for a large-scale accelerator.

The national labs and their future

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crease, R.P.

National laboratories of the USA, born with the atomic age and raised to prominence by the need for scientific superiority during the long Cold War, are facing the most critical challenge: how best to support the nation's current need to improve its international competitiveness through superior technology The charge that the national laboratories are [open quotes]Cold War relics[close quotes] that have outlived their usefulness is based on a misunderstanding of their mission, says Robert P. Crease, historian for Brookhaven National laboratory. Three of the labs-Los Alamos, Sandia, and Lawrence Livermore- are weapons laboratories and their missions must change. Oak Ridge,more » Argonne, and Brookhaven laboratories are multipurpose: basic research facilities with a continuing role in the world of science The national laboratory system traces its origins to the Manhattan Project. Over the next half-century, America's national labs grew into part of the most effective scientific establishment in the world, a much-copied model for management of large-scale scientific programs. In the early years, each lab defined a niche in the complex world of reactors, accelerators, and high-energy proton and electron physics. In the 1970s, several labs worked on basic energy sciences to help solve a national energy crisis. Today, the labs are pressured to do more applied research-research to transfer to the private sector and will have to respond by devising more effective ways of coordinating basic and applied research. But, Crease warns, [open quotes]It also will be essential that any commitment to applied research not take place at the cost of reducing the wellspring of basic research from which so much applied research flows. [open quotes]Making a solid and persuasive case for the independent value of basic research, and for their own role in that enterprise, may be the most important task facing the laboratories in their next half-century,[close quotes].« less

Segregation Increases in Jefferson County Schools. Enrollment Report for 1977-78.

ERIC Educational Resources Information Center

Hamilton, Douglas

Failures of school officials in Jefferson County, Kentucky to desegregate their student bodies since 1975 are cited in this report and substantiated with charts and tables. The resegregation, rather than desegregation, of elementary schools in 1977-78 is documented. It is shown that 12 elementary schools have never been in compliance with…

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

PubMed Central

Williams, Brett; Sifris, Adiva; Lynch, Marty

2016-01-01

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. PMID:27524924

Assessment of Student Learning in Modern Experiments in the Introductory Calculus-Based Physics Labs

NASA Astrophysics Data System (ADS)

Woodahl, Brian; Ross, John; Lang, Sarah; Scott, Derek; Williams, Jeremy

2010-10-01

With the advent of newer microelectronic sensors it's now possible to modernize introductory physics labs with the latest technology and this may allow for enhanced student participation/learning in the experiments. For example, force plate sensors can digitize and record the force on an object, later it can be analyzed in detail (i.e, impulse from force vs. time). Small 3-axis accelerometers can record 3-dim, time-dependent acceleration of objects undergoing complex motions. These devices are small, fairly easy to use, and importantly, are likely to enhance student learning by ``personalizing'' data collection, i.e. making the student an active part of the measurement process and no longer a passive observer. To assess whether these new high-tech labs enhance student learning, we have implemented pre- and post- test sessions to measure the effectiveness of student learning. Four of our calculus-based lab sections were used: Two sections the control group, using the previous ``old technology'' labs, the other two, the experimental group, using the new ``modern technology'' labs. Initial returns of assessment data offer some surprising insight.

3D Animations for Exploring Nucleon Structure

NASA Astrophysics Data System (ADS)

Gorman, Waverly; Burkardt, Matthias

2016-09-01

Over the last few years many intuitive pictures have been developed for the interpretation of electron hadron scattering experiments, such as a mechanism for transverse single-spin asymmetries in semi-inclusive deep-inelastic scattering experiments. While Dr. Burkardt's pictures have been helpful for many researchers in the field, they are still difficult to visualize for broader audiences since they rely mostly on 2-dimensional static images. In order to make more accessible for a broader audience what can be learned from Jefferson Lab experiments, we have started to work on developing 3-dimensional animations for these processes. The goal is to enable the viewer to repeatedly look at the same microscopic mechanism for a specific reaction, with the viewpoint of the observer changing. This should help an audience that is not so familiar with these reactions to better understand what can be learned from various experiments at Jefferson Lab aimed at exploring the nucleon structure. Jefferson Lab Minority/Female Undergraduate Research Assistantship.

2017 QCD Evolution 2017

NASA Astrophysics Data System (ADS)

2017-05-01

The QCD Evolution 2017 workshop was held at Jefferson Lab, May 22-26, 2017. The workshop is a continuation of a series of workshops held during six consecutive years, in 2011, 2012, 2013, 2015 at Jefferson Lab, and in 2014 in Santa Fe, NM, and in 2016 at the National Institute for Subatomic Physics (Nikhef) in Amsterdam. With the rapid developments in our understanding of the evolution of parton distributions including TMDs, GPDs, low-x, higher-twist correlation functions, and the associated progress in perturbative QCD, lattice QCD and effective field theory techniques, we look forward to yet another exciting meeting in 2017. The program of QCD Evolution 2017 will pay special attention to the topics of importance for ongoing experiments, in the full range from Jefferson Lab energies to RHIC and LHC energies or future experiments such as a future Electron Ion Collider, recently recommended as a highest priority in U.S. Department of Energy's 2015 Long Range Plan for Nuclear Science.

The Effects of Space-Charge on the Dynamics of the Ion Booster in the Jefferson Lab EIC (JLEIC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bogacz, Alex; Nissen, Edward

Optimization of the booster synchrotron design to operate in the extreme space-charge dominated regime is proposed. This study is motivated by the ultra-high luminosity promised by the JLEIC accelerator complex, which poses several beam dynamics and lattice design challenges for its individual components. We examine the effects of space charge on the dynamics of the booster synchrotron for the proposed JLEIC electron ion collider. This booster will inject and accumulate protons and heavy ions at an energy of 280 MeV and then engage in a process of acceleration and electron cooling to bring it to its extraction energy of 8more » GeV. This would then be sent into the ion collider ring part of JLEIC. In order to examine the effects of space charge on the dynamics of this process we use the software SYNERGIA.« less

High-intensity positron microprobe at Jefferson Lab

DOE PAGES

Golge, Serkan; Vlahovic, Branislav; Wojtsekhowski, Bogdan B.

2014-06-19

We present a conceptual design for a novel continuous wave electron-linac based high-intensity 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. The performance of the integrated beamline has been verified through computational studies. The computational results include Monte Carlo calculations of the optimized electron/positron beam energies, converter target thickness, synchronized raster system,more » transport of the beam from the converter target to the moderator, extraction of the beam from the channel, and moderation efficiency calculations. For the extraction of positrons from the magnetic channel a magnetic field terminator plug prototype has been built and experimental data on the effectiveness of this prototype are presented. The dissipation of the heat away from the converter target and radiation protection measures are also discussed.« less

Thomas Jefferson's Road to the White House. Teaching with Historic Places.

ERIC Educational Resources Information Center

Hunter, Kathleen

This unit focuses on Thomas Jefferson's route from his home at Monticello in Virginia to the White House when he traveled to Washington in November of 1800 for the upcoming presidential election. The document traces his journey by phaeton, a four wheeled light carriage, from Monticello to: (1) James Madison's home at Montpelier, a distance of 28…

Chemical quality of bottom sediments in selected streams, Jefferson County, Kentucky, April-July 1992

USGS Publications Warehouse

Moore, B.L.; Evaldi, R.D.

1995-01-01

Bottom sediments from 25 stream sites in Jefferson County, Ky., were analyzed for percent volatile solids and concentrations of nutrients, major metals, trace elements, miscellaneous inorganic compounds, and selected organic compounds. Statistical high outliers of the constituent concentrations analyzed for in the bottom sediments were defined as a measure of possible elevated concentrations. Statistical high outliers were determined for at least 1 constituent at each of 12 sampling sites in Jefferson County. Of the 10 stream basins sampled in Jefferson County, the Middle Fork Beargrass Basin, Cedar Creek Basin, and Harrods Creek Basin were the only three basins where a statistical high outlier was not found for any of the measured constituents. In the Pennsylvania Run Basin, total volatile solids, nitrate plus nitrite, and endrin constituents were statistical high outliers. Pond Creek was the only basin where five constituents were statistical high outliers-barium, beryllium, cadmium, chromium, and silver. Nitrate plus nitrite and copper constituents were the only statistical high outliers found in the Mill Creek Basin. In the Floyds Fork Basin, nitrate plus nitrite, phosphorus, mercury, and silver constituents were the only statistical high outliers. Ammonia was the only statistical high outlier found in the South Fork Beargrass Basin. In the Goose Creek Basin, mercury and silver constituents were the only statistical high outliers. Cyanide was the only statistical high outlier in the Muddy Fork Basin.

Berkeley Lab Training

Science.gov Websites

Berkeley Lab Berkeley Lab A-Z Index Phone Book Jobs Search DOE Help Berkeley Lab Training Welcome Welcome to Berkeley Lab Training! Login to access your LBNL Training Profile. This provides quick access to all of the courses you need. Look below, to learn about different types of training available at

NASA's GeneLab Phase II: Federated Search and Data Discovery

NASA Technical Reports Server (NTRS)

Berrios, Daniel C.; Costes, Sylvain V.; Tran, Peter B.

2017-01-01

GeneLab is currently being developed by NASA to accelerate 'open science' biomedical research in support of the human exploration of space and the improvement of life on earth. Phase I of the four-phase GeneLab Data Systems (GLDS) project emphasized capabilities for submission, curation, search, and retrieval of genomics, transcriptomics and proteomics ('omics') data from biomedical research of space environments. The focus of development of the GLDS for Phase II has been federated data search for and retrieval of these kinds of data across other open-access systems, so that users are able to conduct biological meta-investigations using data from a variety of sources. Such meta-investigations are key to corroborating findings from many kinds of assays and translating them into systems biology knowledge and, eventually, therapeutics.

NASAs GeneLab Phase II: Federated Search and Data Discovery

NASA Technical Reports Server (NTRS)

Berrios, Daniel C.; Costes, Sylvain; Tran, Peter

2017-01-01

GeneLab is currently being developed by NASA to accelerate open science biomedical research in support of the human exploration of space and the improvement of life on earth. Phase I of the four-phase GeneLab Data Systems (GLDS) project emphasized capabilities for submission, curation, search, and retrieval of genomics, transcriptomics and proteomics (omics) data from biomedical research of space environments. The focus of development of the GLDS for Phase II has been federated data search for and retrieval of these kinds of data across other open-access systems, so that users are able to conduct biological meta-investigations using data from a variety of sources. Such meta-investigations are key to corroborating findings from many kinds of assays and translating them into systems biology knowledge and, eventually, therapeutics.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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 receivesmore » 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.« less

Techniques for estimating the quantity and quality of storm runoff from urban watersheds of Jefferson County, Kentucky

USGS Publications Warehouse

Evaldi, R.D.; Moore, B.L.

1994-01-01

Linear regression models are presented for estimating storm-runoff volumes, and mean con- centrations and loads of selected constituents in storm runoff from urban watersheds of Jefferson County, Kentucky. Constituents modeled include dissolved oxygen, biochemical and chemical oxygen demand, total and suspended solids, volatile residue, nitrogen, phosphorus and phosphate, calcium, magnesium, barium, copper, iron, lead, and zinc. Model estimations are a function of drainage area, percentage of impervious area, climatological data, and land uses. Estimation models are based on runoff volumes, and concen- trations and loads of constituents in runoff measured at 6 stormwater outfalls and 25 streams in Jefferson County.

Assessment of Historic Landscape, Highway 45 Borrow Pit, Jefferson Parish, Louisiana

DTIC Science & Technology

2003-10-01

Resources Survey of the Mississippi River -Gulf Outlet, Orleans and St. Bernard Parishes , Louisiana . Submitted to the New Orleans District, U.S. Army...US Army Corps of Engineers New Orleans District ASSESSMENT OF HISTORIC LANDSCAPE, HIGHWAY 45 BORROW PIT, JEFFERSON PARISH , LOUISIANA Final Report...LaFourche and Belle Pass forming the western boundary, and the Mississippi River and Red Pass forming the eastern boundary. It encompasses approximately

NASA Videofile of Solar Eclipse from Jefferson City, Missouri

NASA Image and Video Library

2017-08-21

During the eclipse, 14 states across the U.S. were in the path of totality and experienced more than two minutes of darkness in the middle of the day – with a partial eclipse viewable all across North America. The broadcast – Eclipse Across America: Through the Eyes of NASA – covered locations along the path of totality, from Oregon to South Carolina including public reactions from all ages. During this event, NASA Glenn Research Center celebrates the eclipse at the capital eclipse event in Jefferson City, MO

Optum Labs: building a novel node in the learning health care system.

PubMed

Wallace, Paul J; Shah, Nilay D; Dennen, Taylor; Bleicher, Paul A; Bleicher, Paul D; Crown, William H

2014-07-01

Unprecedented change in the US health care system is being driven by the rapid uptake of health information technology and national investments in multi-institution research networks comprising academic centers, health care delivery systems, and other health system components. An example of this changing landscape is Optum Labs, a novel network "node" that is bringing together new partners, data, and analytic techniques to implement research findings in health care practice. Optum Labs was founded in early 2013 by Mayo Clinic and Optum, a commercial data, infrastructure services, and care organization that is part of UnitedHealth Group. Optum Labs now has eleven collaborators and a database of deidentified information on more than 150 million people that is compliant with the Health Insurance Portability and Accountability Act (HIPAA) of 1996. This article describes the early progress of Optum Labs. The combination of the diverse collaborator perspectives with rich data, including deep patient and provider information, is intended to reveal new insights about diseases, treatments, and patients' behavior to guide changes in practice. Practitioners' involvement in agenda setting and translation of findings into practical care innovations accelerates the implementation of research results. Furthermore, feedback loops from the clinic help Optum Labs expand on successes and give quick attention to challenges as they emerge. Project HOPE—The People-to-People Health Foundation, Inc.

Operating Experience and Reliability Improvements on the 5 kW CW Klystron at Jefferson Lab

NASA Astrophysics Data System (ADS)

Nelson, R.; Holben, S.

1997-05-01

With substantial operating hours on the RF system, considerable information on reliability of the 5 kW CW klystrons has been obtained. High early failure rates led to examination of the operating conditions and failure modes. Internal ceramic contamination caused premature failure of gun potting material and ultimate tube demise through arcing or ceramic fracture. A planned course of repotting and reconditioning of approximately 300 klystrons, plus careful attention to operating conditions and periodic analysis of operational data, has substantially reduced the failure rate. It is anticipated that implementation of planned supplemental monitoring systems for the klystrons will allow most catastrophic failures to be avoided. By predicting end of life, tubes can be changed out before they fail, thus minimizing unplanned downtime. Initial tests have also been conducted on this same klystron operated at higher voltages with resultant higher output power. The outcome of these tests will provide information to be considered for future upgrades to the accelerator.

Industrialization of the nitrogen-doping preparation for SRF cavities for LCLS-II

DOE PAGES

Gonnella, D.; Aderhold, S.; Burrill, A.; ...

2017-12-02

The Linac Coherent Light Source II (LCLS-II) is a new state-of-the-art coherent X-ray source being constructed at SLAC National Accelerator Laboratory. It employs 280 superconducting radio frequency (SRF) cavities in order operate in continuous wave (CW) mode. To reduce the overall cryogenic cost of such a large accelerator, nitrogen-doping of the SRF cavities is being used. Nitrogen-doping has consistently been shown to increase the efficiency of SRF cavities operating in the 2.0 K regime and at medium fields (15–20 MV/m) in vertical cavity tests and horizontal cryomodule tests. While nitrogen-doping’s efficacy for improvement of cavity performance was demonstrated at threemore » independent labs, Fermilab, Jefferson Lab, and Cornell University, transfer of the technology to industry for LCLS-II production was not without challenges. Here in this paper, we present results from the beginning of LCLS-II cavity production. We discuss qualification of the cavity vendors and the first cavities from each vendor. Finally, we demonstrate that nitrogen-doping has been successfully transferred to SRF cavity vendors, resulting in consistent production of cavities with better cryogenic efficiency than has ever been achieved for a large-scale accelerator.« less

Industrialization of the nitrogen-doping preparation for SRF cavities for LCLS-II

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gonnella, D.; Aderhold, S.; Burrill, A.

The Linac Coherent Light Source II (LCLS-II) is a new state-of-the-art coherent X-ray source being constructed at SLAC National Accelerator Laboratory. It employs 280 superconducting radio frequency (SRF) cavities in order operate in continuous wave (CW) mode. To reduce the overall cryogenic cost of such a large accelerator, nitrogen-doping of the SRF cavities is being used. Nitrogen-doping has consistently been shown to increase the efficiency of SRF cavities operating in the 2.0 K regime and at medium fields (15–20 MV/m) in vertical cavity tests and horizontal cryomodule tests. While nitrogen-doping’s efficacy for improvement of cavity performance was demonstrated at threemore » independent labs, Fermilab, Jefferson Lab, and Cornell University, transfer of the technology to industry for LCLS-II production was not without challenges. Here in this paper, we present results from the beginning of LCLS-II cavity production. We discuss qualification of the cavity vendors and the first cavities from each vendor. Finally, we demonstrate that nitrogen-doping has been successfully transferred to SRF cavity vendors, resulting in consistent production of cavities with better cryogenic efficiency than has ever been achieved for a large-scale accelerator.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gonnella, D.; Aderhold, S.; Burrill, A.

The Linac Coherent Light Source II (LCLS-II) is a new state-of-the-art coherent X-ray source being constructed at SLAC National Accelerator Laboratory. It employs 280 superconducting radio frequency (SRF) cavities in order operate in continuous wave (CW) mode. To reduce the overall cryogenic cost of such a large accelerator, nitrogen-doping of the SRF cavities is being used. Nitrogen-doping has consistently been shown to increase the efficiency of SRF cavities operating in the 2.0 K regime and at medium fields (15–20 MV/m) in vertical cavity tests and horizontal cryomodule tests. While nitrogen-doping’s efficacy for improvement of cavity performance was demonstrated at threemore » independent labs, Fermilab, Jefferson Lab, and Cornell University, transfer of the technology to industry for LCLS-II production was not without challenges. Here in this paper, we present results from the beginning of LCLS-II cavity production. We discuss qualification of the cavity vendors and the first cavities from each vendor. Finally, we demonstrate that nitrogen-doping has been successfully transferred to SRF cavity vendors, resulting in consistent production of cavities with better cryogenic efficiency than has ever been achieved for a large-scale accelerator.« less

Universal Design for Learning and the Port Jefferson School District: A Needs Assessment

ERIC Educational Resources Information Center

Sladek-Maharg, Tara S.

2011-01-01

Purpose: This applied doctoral project purpose was to determine what was needed to implement UDL in the Port Jefferson school district, specifically determining district strengths and weaknesses. Data were collected with researcher-created surveys given to administrators, faculty members, and members of the parent organizations and the district's…

Measurements of GEp/GMp to high Q2 and search for 2{gamma} contribution in elastic ep at Jefferson Lab

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vina Punjabi, Charles Perdrisat

2010-05-01

The ratio, μpGEp/GMp, where μp is the proton magnetic moment, has been measured extensively over the last decade at the Jefferson Laboratory, using the polarization transfer method. This ratio is extracted directly from the measured ratio of transverse to longitudinal polarizations components of the recoiling proton in elastic electron-proton scattering. The polarization transfer results are of unprecedented high precision and accuracy, due in large part to the small systematic uncertainties associated with the experimental technique. Prior to these measurements, the form factors were empirically observed to exhibit dipole forms, such that μpGEp/GMp ≈ 1 over all regions of momentum transfermore » studied. With the Hall A results confirming that the ratio μpGEp/GMp shows a steady decrease below unity as a function of Q2, beginning around Q2 ≈ 1 GeV2, discussions revolving around the implication of this deviation from dipole behavior for the structure of the proton have been accompanied by renewed experimental interest in these elastic form factors. Starting in the fall of 2007, two new experiments, GEp-III and GEp-2γ in Hall C at JLab, measured the form factor ratio, GEp/GMp; the GEp-III experiment pushed the highest Q2 limit from 5.6 to 8.49 GeV2, with intermediate points at 5.2 and 6.8 GeV2, and the GEp-2γ experiment measured the ratio in three different kinematics at the constant value Q2=2.5 GeV2, by changing beam energy and detector angles. Preliminary results from both experiments are reported.« less

Designing a ruggedisation lab to characterise materials for harsh environments.

PubMed

Frazzette, Nicholas; Jethva, Janak; Mehta, Khanjan; Stapleton, Joshua J; Randall, Clive

Designing products for use in developing countries presents a unique set of challenges including harsh operating environments, costly repairs and maintenance, and users with varying degrees of education and device familiarity. For products to be robust, adaptable and durable, they need to be ruggedised for environmental factors such as high temperature and humidity as well as different operational conditions such as shock and chemical exposure. The product characterisation and ruggedisation processes require specific expertise and resources that are seldom available outside of large corporations and elite national research labs. There is no standardised process since product needs strongly depend on the context and user base, making it particularly onerous for underfunded start-ups and academic groups. Standardised protocols that identify essential lab testing regimens for specific contexts and user groups can complement field-testing and accelerate the product development process while reducing costs. This article synthesises current methods and strategies for product testing employed by large corporations as well as defence-related entities. A technological and organisational framework for a service-for-fee product characterisation and ruggedisation lab that reduces costs and shortens the timespan from product invention to commercial launch in harsh settings is presented.

Non-linear Multidimensional Optimization for use in Wire Scanner Fitting

NASA Astrophysics Data System (ADS)

Henderson, Alyssa; Terzic, Balsa; Hofler, Alicia; CASA and Accelerator Ops Collaboration

2013-10-01

To ensure experiment efficiency and quality from the Continuous Electron Beam Accelerator at Jefferson Lab, beam energy, size, and position must be measured. Wire scanners are devices inserted into the beamline to produce measurements which are used to obtain beam properties. Extracting physical information from the wire scanner measurements begins by fitting Gaussian curves to the data. This study focuses on optimizing and automating this curve-fitting procedure. We use a hybrid approach combining the efficiency of Newton Conjugate Gradient (NCG) method with the global convergence of three nature-inspired (NI) optimization approaches: genetic algorithm, differential evolution, and particle-swarm. In this Python-implemented approach, augmenting the locally-convergent NCG with one of the globally-convergent methods ensures the quality, robustness, and automation of curve-fitting. After comparing the methods, we establish that given an initial data-derived guess, each finds a solution with the same chi-square- a measurement of the agreement of the fit to the data. NCG is the fastest method, so it is the first to attempt data-fitting. The curve-fitting procedure escalates to one of the globally-convergent NI methods only if NCG fails, thereby ensuring a successful fit. This method allows for the most optimal signal fit and can be easily applied to similar problems. Financial support from DoE, NSF, ODU, DoD, and Jefferson Lab.

Experiences in supporting the structured collection of cancer nanotechnology data using caNanoLab

PubMed Central

Gaheen, Sharon; Lijowski, Michal; Heiskanen, Mervi; Klemm, Juli

2015-01-01

Summary The cancer Nanotechnology Laboratory (caNanoLab) data portal is an online nanomaterial database that allows users to submit and retrieve information on well-characterized nanomaterials, including composition, in vitro and in vivo experimental characterizations, experimental protocols, and related publications. Initiated in 2006, caNanoLab serves as an established resource with an infrastructure supporting the structured collection of nanotechnology data to address the needs of the cancer biomedical and nanotechnology communities. The portal contains over 1,000 curated nanomaterial data records that are publicly accessible for review, comparison, and re-use, with the ultimate goal of accelerating the translation of nanotechnology-based cancer therapeutics, diagnostics, and imaging agents to the clinic. In this paper, we will discuss challenges associated with developing a nanomaterial database and recognized needs for nanotechnology data curation and sharing in the biomedical research community. We will also describe the latest version of caNanoLab, caNanoLab 2.0, which includes enhancements and new features to improve usability such as personalized views of data and enhanced search and navigation. PMID:26425409

Aerogel mass production for the CLAS12 RICH: Novel characterization methods and optical performance

NASA Astrophysics Data System (ADS)

Contalbrigo, M.; Balossino, I.; Barion, L.; Barnyakov, A. Yu.; Battaglia, G.; Danilyuk, A. F.; Katcin, A. A.; Kravchenko, E. A.; Mirazita, M.; Movsisyan, A.; Orecchini, D.; Pappalardo, L. L.; Squerzanti, S.; Tomassini, S.; Turisini, M.

2017-12-01

A large area ring-imaging Cherenkov detector has been designed to provide clean hadron identification capabilities in the momentum range from 3 GeV/c to 8 GeV/c for the CLAS12 experiments at the Jefferson Lab upgraded 12 GeV continuous electron beam accelerator facility. The adopted solution foresees a novel hybrid optics design based on an aerogel radiator, composite mirrors and densely-packed and highly-segmented photon detectors. Cherenkov light will either be imaged directly (forward tracks) or after two mirror reflections (large angle tracks). The status of the aerogel mass-production and the assessment studies of the aerogel optical performance are here reported.

e-Learning - Physics Labs

NASA Astrophysics Data System (ADS)

Mohottala, Hashini

2014-03-01

The general student population enrolled in any college level class is highly diverse. An increasing number of ``nontraditional'' students return to college and most of these students follow distance learning degree programs while engaging in their other commitments, work and family. However, those students tend to avoid taking science courses with labs, mostly because of the incapability of remotely completing the lab components in such courses. In order to address this issue, we have come across a method where introductory level physics labs can be taught remotely. In this process a lab kit with the critical lab components that can be easily accessible are conveniently packed into a box and distributed among students at the beginning of the semester. Once the students are given the apparatus they perform the experiments at home and gather data All communications with reference to the lab was done through an interactive user-friendly webpage - Wikispaces (WikiS). Students who create pages on WikiS can submit their lab write-ups, embed videos of the experiments they perform, post pictures and direct questions to the lab instructor. The students who are enrolled in the same lab can interact with each other through WikiS to discuss labs and even get assistance.

VIEW OF OFFICES IN BUILDING 111. BUILDING 111 ALSO HOUSED ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF OFFICES IN BUILDING 111. BUILDING 111 ALSO HOUSED A PHOTOGRAPHY LAB AND A PRINT SHOP. (11/28/62) - Rocky Flats Plant, Offices, Print Shop & Photography Lab, Northwest quad of plant near terminus of Central Avenue, Golden, Jefferson County, CO

Vehicle Systems Integration Laboratory Accelerates Powertrain Development

ScienceCinema

None

2018-05-23

ORNL's Vehicle Systems Integration (VSI) Laboratory accelerates the pace of powertrain development by performing prototype research and characterization of advanced systems and hardware components. The VSI Lab is capable of accommodating a range of platforms from advanced light-duty vehicles to hybridized Class 8 powertrains with the goals of improving overall system efficiency and reducing emissions.

Big Machines and Big Science: 80 Years of Accelerators at Stanford

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loew, Gregory

2008-12-16

Longtime SLAC physicist Greg Loew will present a trip through SLAC's origins, highlighting its scientific achievements, and provide a glimpse of the lab's future in 'Big Machines and Big Science: 80 Years of Accelerators at Stanford.'

Which Accelerates Faster--A Falling Ball or a Porsche?

ERIC Educational Resources Information Center

Rall, James D.; Abdul-Razzaq, Wathiq

2012-01-01

An introductory physics experiment has been developed to address the issues seen in conventional physics lab classes including assumption verification, technological dependencies, and real world motivation for the experiment. The experiment has little technology dependence and compares the acceleration due to gravity by using position versus time…

Microgravity acceleration measurement and environment characterization science (17-IML-1)

NASA Technical Reports Server (NTRS)

1992-01-01

The Space Acceleration Measurement System (SAMS) is a general purpose instrumentation system designed to measure the accelerations onboard the Shuttle Orbiter and Shuttle/Spacelab vehicles. These measurements are used to support microgravity experiments and investigation into the microgravity environment of the vehicle. Acceleration measurements can be made at locations remote from the SAMS main instrumentation unit by the use of up to three remote triaxial sensor heads. The prime objective for SAMS on the International Microgravity Lab (IML-1) mission will be to measure the accelerations experienced by the Fluid Experiment System (FES). The SAMS acceleration measurements for FES will be complemented by low level, low frequency acceleration measurements made by the Orbital Acceleration Research Experiment (OARE) installed on the shuttle. Secondary objectives for SAMS will be to measure accelerations at several specific locations to enable the acceleration transfer function of the Spacelab module to be analyzed. This analysis effort will be in conjunction with similar measurements analyses on other Spacelab missions.

Occipital Neuralgia after Occipital Cervical Fusion to Treat an Unstable Jefferson Fracture

PubMed Central

Kong, Seong Ju; Park, Jin Hoon

2012-01-01

In this report we describe a patient with an unstable Jefferson fracture who was treated by occipitocervical fusion and later reported sustained postoperative occipital neuralgia. A 70-year-old male was admitted to our center with a Jefferson fracture induced by a car accident. Preoperative lateral X-ray revealed an atlanto-dens interval of 4.8mm and a C1 canal anterior-posterior diameter of 19.94mm. We performed fusion surgery from the occiput to C5 without decompression of C1. The patient reported sustained continuous pain throughout the following year despite strong analgesics. The pain dermatome was located mainly in the great occipital nerve territory and posterior neck. Magnetic resonance images revealed no evidence of cord compression, however a C1 lamina compressed dural sac and C2 root compression could not be excluded. We performed bilateral C2 root decompression via a C1 laminectomy. After decompression, bilateral C2 root redundancy was identified by palpation. After decompression surgery, pain was reduced. This case indicates that occipital neuralgia, suggesting the need for diagnostic block, should be considered in the differential diagnosis of patients with sustained occipital headache after occipitocervical fusion surgery. PMID:25983846

The BDX experiment at Jefferson Laboratory

NASA Astrophysics Data System (ADS)

Celentano, Andrea

2015-06-01

The existence of MeV-GeV dark matter (DM) is theoretically well motivated but remarkably unexplored. The Beam Dump eXperiment (BDX) at Jefferson Laboratory aims to investigate this mass range. Dark matter particles will be detected trough scattering on a segmented, plastic scintillator detector placed downstream of the beam-dump at one of the high intensity JLab experimental Halls. The experiment will collect up to 1022 electrons-on-target (EOT) in a one-year period. For these conditions, BDX is sensitive to the DM-nucleon elastic scattering at the level of a thousand counts per year, and is only limited by cosmogenic backgrounds. The experiment is also sensitive to DM-electron elastic and inelastic scattering, at the level of 10 counts/year. The foreseen signal for these channels is an high-energy (> 100 MeV) electromagnetic shower, with almost no background. The experiment, has been presented in form of a Letter of Intent to the laboratory, receiving positive feedback, and is currently being designed.

An Inventory of Cocurricular Drama Programs in the Secondary Schools of Jefferson County, Kentucky.

ERIC Educational Resources Information Center

Hoover, Nancy Roahrig

In order to compile an inventory of secondary school cocurricular dramatics programs in the Jefferson County, Kentucky, public schools, eleven principals, eighteen teachers, and eighty students were randomly selected from thirteen high schools, five junior high schools, and five middle schools. Respondents completed questionnaires concerning the…

Innovation Incubator: Whisker Labs Technical Evaluation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sparn, Bethany F.; Frank, Stephen M.; Earle, Lieko

The Wells Fargo Innovation Incubator (IN2) is a program to foster and accelerate startup companies with commercial building energy-efficiency and demand management technologies. The program is funded by the Wells Fargo Foundation and co-administered by the National Renewable Energy Laboratory (NREL). Whisker Labs, an Oakland, California-based company, was one of four awardees in the first IN2 cohort and was invited to participate in the program because of its novel electrical power sensing technology for circuit breakers. The stick-on Whisker meters install directly on the front face of the circuit breakers in an electrical panel using adhesive, eliminating the need tomore » open the panel and install current transducers (CTs) on the circuit wiring.« less

Evaluation of cores from Jefferson Highway near Airline Highway : technical assistance report 16-03TA-C.

DOT National Transportation Integrated Search

2016-09-01

This technical assistance report documents the investigation conducted by the Louisiana Transportation Research Center (LTRC) of the cored concrete from Westbound Jefferson Highway near Airline Highway in Baton Rouge, LA. The petrographic analysis sh...

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

ERIC Educational Resources Information Center

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)

A Comparative Study on Real Lab and Simulation Lab in Communication Engineering from Students' Perspectives

ERIC Educational Resources Information Center

Balakrishnan, B.; Woods, P. C.

2013-01-01

Over the years, rapid development in computer technology has engendered simulation-based laboratory (lab) in addition to the traditional hands-on (physical) lab. Many higher education institutions adopt simulation lab, replacing some existing physical lab experiments. The creation of new systems for conducting engineering lab activities has raised…

Kinematic Labs with Mobile Devices

NASA Astrophysics Data System (ADS)

Kinser, Jason M.

2015-07-01

This book provides 13 labs spanning the common topics in the first semester of university-level physics. Each lab is designed to use only the student's smartphone, laptop and items easily found in big-box stores or a hobby shop. Each lab contains theory, set-up instructions and basic analysis techniques. All of these labs can be performed outside of the traditional university lab setting and initial costs averaging less than 8 per student, per lab.

MethLAB

PubMed Central

Kilaru, Varun; Barfield, Richard T; Schroeder, James W; Smith, Alicia K

2012-01-01

Recent evidence suggests that DNA methylation changes may underlie numerous complex traits and diseases. The advent of commercial, array-based methods to interrogate DNA methylation has led to a profusion of epigenetic studies in the literature. Array-based methods, such as the popular Illumina GoldenGate and Infinium platforms, estimate the proportion of DNA methylated at single-base resolution for thousands of CpG sites across the genome. These arrays generate enormous amounts of data, but few software resources exist for efficient and flexible analysis of these data. We developed a software package called MethLAB (http://genetics.emory.edu/conneely/MethLAB) using R, an open source statistical language that can be edited to suit the needs of the user. MethLAB features a graphical user interface (GUI) with a menu-driven format designed to efficiently read in and manipulate array-based methylation data in a user-friendly manner. MethLAB tests for association between methylation and relevant phenotypes by fitting a separate linear model for each CpG site. These models can incorporate both continuous and categorical phenotypes and covariates, as well as fixed or random batch or chip effects. MethLAB accounts for multiple testing by controlling the false discovery rate (FDR) at a user-specified level. Standard output includes a spreadsheet-ready text file and an array of publication-quality figures. Considering the growing interest in and availability of DNA methylation data, there is a great need for user-friendly open source analytical tools. With MethLAB, we present a timely resource that will allow users with no programming experience to implement flexible and powerful analyses of DNA methylation data. PMID:22430798

A threshold gas Cerenkov detector for the spin asymmetries of the nucleon experiment

DOE PAGES

Armstrong, Whitney R.; Choi, Seonho; Kaczanowicz, Ed; ...

2015-09-26

In this study, we report on the design, construction, commissioning, and performance of a threshold gas Cerenkov counter in an open configuration, which operates in a high luminosity environment and produces a high photo-electron yield. Part of a unique open geometry detector package known as the Big Electron Telescope Array, this Cerenkov counter served to identify scattered electrons and reject produced pions in an inclusive scattering experiment known as the Spin Asymmetries of the Nucleon Experiment E07-003 at the Thomas Jefferson National Accelerator Facility (TJNAF) also known as Jefferson Lab. The experiment consisted of a measurement of double spin asymmetriesmore » A || and A ⊥ of a polarized electron beam impinging on a polarized ammonia target. The Cerenkov counter's performance is characterised by a yield of about 20 photoelectrons per electron or positron track. Thanks to this large number of photoelectrons per track, the Cerenkov counter had enough resolution to identify electron-positron pairs from the conversion of photons resulting mainly from π 0 decays.« less

PREFACE: 17th Pan-American Synchrotron Radiation Instrumentation Conference SRI2013

NASA Astrophysics Data System (ADS)

Williams, Gwyn P.; Revesz, Peter; Arp, Uwe

2014-03-01

These proceedings are a collection of the articles presented at the seventeenth Pan-American Synchrotron Radiation Instrumentation Conference SRI2013, held on the campus of the National Institute of Standards and Technology (NIST), located in Gaithersburg, Maryland, United States of America, 19-21 June, 2013. SRI2013 was jointly hosted by the Cornell University Cornell High Energy Synchrotron Source (CHESS), the Thomas Jefferson National Accelerator Facility (Jefferson Lab), and the Synchrotron Ultraviolet Radiation Facility (SURF III) at NIST. This meeting's focus was clearly on instrumentation, thus fulfilling the intent of this SRI meeting series, which was initiated at NIST, then the National Bureau of Standards (NBS), in 1979. SRI2013 hosted more than 150 delegates, despite the new US governmental travel restrictions. This proceedings series aims to be an essential reference work for practitioners in the field. It primarily documents the evolution and development of techniques, but also recent scientific advances, that were presented during the two and a half days of the conference. We are extremely thankful to all the authors who contributed to making these proceedings a volume of reference as well as to the reviewers for their careful reading and constructive recommendations for improving the articles. Great thanks go to Robert Dragoset at NIST, for creating and maintaining the conference website and generating the conference logo. We are also thankful for the excellent support we received from the Conference Program at NIST, especially Kathy Kilmer and Angela Ellis. And we would like to dedicate these proceedings to the memory of Kathy Kilmer, who passed away on 15 October, 2013. NIST will not be the same without her. The Co-Editors: Uwe Arp (SURF/NIST) Peter Reversz (CHESS) Gwyn P Williams (Jefferson Lab)

Teachers' Perspectives on Online Virtual Labs vs. Hands-On Labs in High School Science

NASA Astrophysics Data System (ADS)

Bohr, Teresa M.

This study of online science teachers' opinions addressed the use of virtual labs in online courses. A growing number of schools use virtual labs that must meet mandated laboratory standards to ensure they provide learning experiences comparable to hands-on labs, which are an integral part of science curricula. The purpose of this qualitative case study was to examine teachers' perceptions of the quality and effectiveness of high school virtual labs. The theoretical foundation was constructivism, as labs provide student-centered activities for problem solving, inquiry, and exploration of phenomena. The research questions focused on experienced teachers' perceptions of the quality of virtual vs. hands-on labs. Data were collected through survey questions derived from the lab objectives of The Next Generation Science Standards . Eighteen teachers rated the degree of importance of each objective and also rated how they felt virtual labs met these objectives; these ratings were reported using descriptive statistics. Responses to open-ended questions were few and served to illustrate the numerical results. Many teachers stated that virtual labs are valuable supplements but could not completely replace hands-on experiences. Studies on the quality and effectiveness of high school virtual labs are limited despite widespread use. Comprehensive studies will ensure that online students have equal access to quality labs. School districts need to define lab requirements, and colleges need to specify the lab experience they require. This study has potential to inspire positive social change by assisting science educators, including those in the local school district, in evaluating and selecting courseware designed to promote higher order thinking skills, real-world problem solving, and development of strong inquiry skills, thereby improving science instruction for all high school students.

TangoLab-2 Card Troubleshooting

NASA Image and Video Library

2017-10-17

iss053e105442 (Oct. 17, 2017) --- Flight Engineer Mark Vande Hei swaps out a payload card from the TangoLab-1 facility and places into the TangoLab-2 facility. TangoLab provides a standardized platform and open architecture for experimental modules called CubeLabs. CubeLab modules may be developed for use in 3-dimensional tissue and cell cultures.

Accelerating Into the Future: From 0 to GeV in a Few Centimeters (LBNL Summer Lecture Series)

ScienceCinema

Leemans, Wim [LOASIS Program, AFRD

2017-12-09

July 8, 2008 Berkeley Lab lecture: By exciting electric fields in plasma-based waveguides, lasers accelerate electrons in a fraction of the distance conventional accelerators require. The Accelerator and Fusion Research Division's LOASIS program, headed by Wim Leemans, has used 40-trillion-watt laser pulses to deliver billion-electron-volt (1 GeV) electron beams within centimeters. Leemans looks ahead to BELLA, 10-GeV accelerating modules that could power a future linear collider.

Final Results from the Jefferson Lab Qweak Experiment

NASA Astrophysics Data System (ADS)

Smith, Gregory

2017-09-01

The Qweak collaboration has unblinded our final result. We briefly describe the e-> p elastic scattering experiment used to extract the asymmetries measured in the two distinct running periods which constituted the experiment. The precision obtained on the final combined asymmetry is +/- 9.3 ppb. Some of the backgrounds and corrections applied in the experiment will be explained and quantified. We then provide the results of several methods we have used to extract consistent values of the proton's weak charge QWp from our asymmetry measurements. We also present results for the strange and axial form factors obtained from a fit to existing parity-violating electron scattering data. In conjunction with existing atomic parity violation results on 133Cs we extract the vector weak quark couplings C1u and C1d. The latter are combined to obtain the neutron's weak charge. From the proton's weak charge we obtain a result for sin2θW at the energy scale of our experiment, a sensitive SM test of the running of sin2θW . We also show the mass reach for new beyond-the-Standard-Model physics obtained from our determination of the proton's weak charge and its uncertainty, and discuss sensitivity to specific models. This work was supported by the U.S. Department of Energy, Office of Science, under Contract DE-AC05-06OR23177, the Natural Sciences and Engineering Research Council of Canada (NSERC), and the National Science Foundation (NSF).

A comparative study on real lab and simulation lab in communication engineering from students' perspectives

NASA Astrophysics Data System (ADS)

Balakrishnan, B.; Woods, P. C.

2013-05-01

Over the years, rapid development in computer technology has engendered simulation-based laboratory (lab) in addition to the traditional hands-on (physical) lab. Many higher education institutions adopt simulation lab, replacing some existing physical lab experiments. The creation of new systems for conducting engineering lab activities has raised concerns among educators on the merits and shortcomings of both physical and simulation labs; at the same time, many arguments have been raised on the differences of both labs. Investigating the effectiveness of both labs is complicated, as there are multiple factors that should be considered. In view of this challenge, a study on students' perspectives on their experience related to key aspects on engineering laboratory exercise was conducted. In this study, the Visual Auditory Read and Kinetic model was utilised to measure the students' cognitive styles. The investigation was done through a survey among participants from Multimedia University, Malaysia. The findings revealed that there are significant differences for most of the aspects in physical and simulation labs.

A Constructivist Cloud Lab.

ERIC Educational Resources Information Center

Emery, Dave

1996-01-01

Describes a lab involving a cloud formation activity that uses the constructivist learning model to get students more involved in creating the lab. Enables students to develop a greater understanding of the concepts involved and more interest in the lab's outcomes. (JRH)

Virtual Reality Lab Assistant

NASA Technical Reports Server (NTRS)

Saha, Hrishikesh; Palmer, Timothy A.

1996-01-01

Virtual Reality Lab Assistant (VRLA) demonstration model is aligned for engineering and material science experiments to be performed by undergraduate and graduate students in the course as a pre-lab simulation experience. This will help students to get a preview of how to use the lab equipment and run experiments without using the lab hardware/software equipment. The quality of the time available for laboratory experiments can be significantly improved through the use of virtual reality technology.

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

ERIC Educational Resources Information Center

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…

LabSkills

ERIC Educational Resources Information Center

O'Brien, Nick

2010-01-01

This article describes LabSkills, a revolutionary teaching tool to improve practical science in schools. LabSkills offers the chance to help improve the exposure that the average Key Stage 5 (age 16-19) student has to practical work. This is a huge area for development being highlighted by universities who are seeing a worryingly growing trend in…

Cross-cultural adaptation of Jefferson scale of empathy-health professions students version: An experience with developing the Tamil translation.

PubMed

Jeyashree, Kathiresan; Kathirvel, Soundappan; Prathibha, Muthu K

2017-01-01

Empathy is a key cognitive attribute among healthcare professionals that fosters better patient- healthcare provider relationships. The Jefferson scale of empathy (JSE) measures self-rated empathy among various groups of healthcare professionals-health professionals, medical students and health professions students (HPS). The authors present the experience in translating the JSE-HPS version into an Indian regional language with insights into the issues faced in every step. With official permission from the Thomas Jefferson University, the authors embarked on the translation proceeding through forward translation (three rounds of modification), back translation (two independent translates), and synthesis of a final translated version. While targeting literary accuracy, the simplicity and comprehensibility of the instrument by the study population were also ensured. Variations in regional dialects and accents across the population were considered. The back-translated version was evaluated for semantic, content, cultural, and technical equivalence. It was then pretested on ten students followed by a group discussion with them to ensure the comprehensibility of the tool and the differences between written and spoken language were addressed through necessary modifications. The Tamil translation of the HPS version of JSE is now approved by and officially available with the Thomas Jefferson University.

The structure of the nucleon: Elastic electromagnetic form factors

DOE PAGES

Punjabi, V.; Perdrisat, C. F.; Jones, M. K.; ...

2015-07-10

Precise proton and neutron form factor measurements at Jefferson Lab, using spin observables, have recently made a significant contribution to the unraveling of the internal structure of the nucleon. Accurate experimental measurements of the nucleon form factors are a test-bed for understanding how the nucleon's static properties and dynamical behavior emerge from QCD, the theory of the strong interactions between quarks. There has been enormous theoretical progress, since the publication of the Jefferson Lab proton form factor ratio data, aiming at reevaluating the picture of the nucleon. We will review the experimental and theoretical developments in this field and discussmore » the outlook for the future.« less

Cycle-Based Budgeting and Continuous Improvement at Jefferson County Public Schools: Year 2 Report

ERIC Educational Resources Information Center

Yan, Bo

2017-01-01

This report documents the second year of implementing Cycle-based Budgeting at Jefferson County Public Schools (Louisville, KY). In addition to aligning another $24.3 million new spending with the district's strategic plan, $20.3 million of existing spending was rolled into the process. Next, the challenges faced by the district to review 105…

RESULTS OF THE 2015 HELIUM PROCESSING OF CEBAF CRYOMODULES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Drury, Michael A.; Humphry, Jr., Frank J.; King, Larry

2016-10-01

Many conference series have adopted the same The CEBAF accelerator at Jefferson Lab consists of an injec-tor and two linacs connected by arcs. Each linac contains 25 cryomodules that are designed to deliver an integrated energy of 2.2 GeV per pass to an electron beam in order to meet 12 GeV energy requirements. Helium processing is a processing technique that is used to reduce field emis-sion (FE) in SRF cavities. Helium processing of the 50 installed linac cryomodules was seen as necessary to support 12 GeV energy requirements. This paper will describe the processing procedure and summarize the results ofmore » this effort.« less

A Beat Frequency RF Modulator for Generation of Low Repetition Rate Electron Microbunches for the CEBAF Polarized Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

John Musson; Reza Kazimi; Benard Poelker

2007-06-25

Fiber-based drive lasers now produce all of the spin-polarized electron beams at CEBAF/Jefferson Lab. The flexibility of these drive lasers, combined with the existing three-beam CEBAF photoinjector Chopper, provides a means to implement a beat frequency technique to produce long time intervals between individual electron microbunches (tens of nanoseconds) by merely varying the nominal 499 MHz drive laser frequency by < 20%. This submission describes the RF Laser modulator that uses a divider and heterodyne scheme to maintain coherence with the accelerator Master Oscillator (MO), while providing delay resolution in increments of 2ns. Some possible uses for such a beammore » are discussed as well as intended future development.« less

Characterization Of Superconducting Samples With SIC System For Thin Film Developments: Status And Recent Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phillips, H. Lawrence; Reece, Charles E.; Valente-Feliciano, Anne-Marie

2014-02-01

Within any thin film development program directed towards SRF accelerating structures, there is a need for an RF characterization device that can provide information about RF properties of small samples. The current installation of the RF characterization device at Jefferson Lab is Surface Impedance Characterization (SIC) system. The data acquisition environment for the system has recently been improved to allow for automated measurement, and the system has been routinely used for characterization of bulk Nb, films of Nb on Cu, MgB{sub 2}, NbTiN, Nb{sub 3}Sn films, etc. We present some of the recent results that illustrate present capabilities and limitationsmore » of the system.« less

Hydrogeologic Factors Affecting Base-Flow Yields in the Jefferson County Area, West Virginia, October-November 2007

USGS Publications Warehouse

Evaldi, Ronald D.; Paybins, Katherine S.; Kozar, Mark D.

2009-01-01

Base-flow yields at approximately the annual 75-percent-duration flow were determined for watersheds in the Jefferson County area, WV, from stream-discharge measurements made during October 31 to November 2, 2007. Five discharge measurements of Opequon Creek defined increased flow from 29,000,000 gallons per day (gal/d) at Carters Ford to 51,400,000 gal/d near Vanville. No flow was observed at 45 of 110 additional stream sites inspected, and discharge at the 65 flowing stream sites ranged from 1,940 to 17,100,000 gallons per day (gal/d). Discharge at 28 springs ranged from no flow to 2,430,000 gal/d. Base-flow yields were computed as the change in stream-channel discharge between measurement sites divided by the change in drainage area between the sites. Yields were negative for losing (influent) channel reaches and positive for gaining (effluent) reaches. Channels in 14 watersheds were determined to have lost flow ranging from -9.6 to -1,770 gallons per day per acre (gal/d/acre). Channels in 51 watersheds were determined to have gained flow ranging from 3.4 to 235,000 gal/d/acre. Water temperature at the stream sites ranged from 5.0 to 16.3 deg C (quarry pumpage), and specific conductance ranged from 51 to 881 microsiemens per centimeter (uS/cm). Water temperature at the springs ranged from 11.5 to 15.0 deg C, and specific conductance ranged from 22 to 958 uS/cm. Large springs in some watersheds in western Jefferson County are adjacent to other watersheds with little or no surface-water discharge; this is probably the result of interbasin transfer of groundwater along faults that dissect the area. Most watersheds located adjacent to the Potomac River in northeastern Jefferson County were not flowing during this study; this is most likely because the Potomac River is deeply incised, and groundwater flows directly to it rather than to the local stream systems in these areas. Except for one watershed with a yield of 651 gal/d/acre, no watersheds in northeastern

Doing More with Less: Cost-effective, Compact Particle Accelerators (489th Brookhaven Lecture)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trbojevic, Dejan

2013-10-22

Replace a 135-ton magnet used for cancer-fighting particle therapies with a magnet that weighs only two tons? Such a swap is becoming possible thanks to new particle accelerator advances being developed by researchers at Brookhaven Lab. With an approach that combines techniques used by synchrotron accelerators with the ability to accept more energy, these new technologies could be used for more than fighting cancer. They could also decrease the lifecycle of byproducts from nuclear power plants and reduce costs for eRHIC—a proposed electron-ion collider for Brookhaven Lab that researchers from around the world would use to explore the glue thatmore » holds together the universe’s most basic building blocks and explore the proton-spin puzzle. During this lecture, Dr. Trbojevic provides an overview of accelerator technologies and techniques—particularly a non-scaling, fixed-focused alternating gradient—to focus particle beams using fewer, smaller magnets. He discusses how these technologies will benefit eRHIC and other applications, including particle therapies being developed to combat cancer.« less

Electric Form Factor of the Neutron

NASA Astrophysics Data System (ADS)

Feuerbach, Robert

2007-10-01

Recent polarization-based precision measurements of the nucleons' elastic electric form factors have led to surprising results. The measurement of the ratio of the proton's electromagnetic form factors, μpGE^p/GM^p, was found to drop nearly linearly with Q^2 out to at least 5 GeV^2, inconsistent with the older Rosenbluth-type experiments. A recent measurement of GE^n, the neutron's electric form-factor saw GE^n does not fall off as quickly as commonly expected up to Q^2 1.5 GeV^2. Extending this study, a precision measurement of GE^n up to Q^2=3.5 GeV^2 was completed in Hall A at Jefferson Lab. The ratio GE^n/GM^n was measured through the beam-target asymmetry A of electrons quasi-elastically scattered off polarized neutrons in the reaction ^3He(e,e' n). The experiment took full advantage of the electron beam, recent target developments, 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 in-beam polarizations in excess of 50%. A medium acceptance (80msr) open-geometry magnetic spectrometer (BigBite) detected the scattered electron, while a geometrically matched neutron detector observed the struck neutron. Preliminary results from this measurement will be discussed and compared to modern calculations of GE^n.

NASA Provides Coast-to-Coast Coverage of Aug. 21 Solar Eclipse (Jefferson City, MO)

NASA Image and Video Library

2017-08-21

On Monday, Aug. 21, NASA provided coast-to-coast coverage of the solar eclipse across America – featuring views of the phenomenon from unique vantage points, including from the ground, from aircraft, and from spacecraft including the ISS, during a live broadcast seen on NASA Television and the agency’s website. This is footage from Jefferson City, Missouri.

Evaluation of hardness and colour change of soft liners after accelerated ageing.

PubMed

Mancuso, Daniela Nardi; Goiato, Marcelo Coelho; Zuccolotti, Bruna Carolina Rossatti; Moreno, Amália; dos Santos, Daniela Micheline

2009-07-01

Soft liners have been developed to offer comfort to denture wearers. However, this comfort is compromised when there is a change in the properties of the material, causing colour change, solubility, absorption and hardening. These characteristics can compromise the longevity of soft liners. The aim of this in vitro study was to investigate the effect of ageing on both the hardness and colour change of two soft liners following accelerated ageing. Two denture liners, one resin based (Trusoft, Bosworth, Illinois, USA) and one silicone based (Ufi Gel P, Voco GMBH, Cuxhaven, Germany), were tested in this study for both hardness (using the Shore A scale) and colour change (using the CIE L*a*b* colour scale), initially and after 1008 hours (6 weeks) of accelerated ageing. Statistical analysis was performed using the unpaired t-test with the Welch correction. These indicated that both materials increased in hardness and underwent colour change after accelerated ageing. The initial hardness of Trusoft was far lower than that of Ufi Gel P (18.2 Shore A units vs 34.8 Shore A units). However, for Trusoft the changes for both hardness (from 18.2 to 52.1 Shore A units) and colour change (16.85 on the CIE L*a*b* colour scale) were greater than those for Ufi Gel P, for which hardness changed from 34.8 to 36.5 Shore A units and the colour change was 5.19 on the CIE L*a*b* colour scale. Ufi Gel P underwent less hardness and colour change after accelerated ageing than Trusoft. On the other hand, the use of Trusoft may be preferable in cases where initial softness is a major consideration, such as when relining an immediate denture after implant surgery.

75 FR 51098 - Protection Island and San Juan Islands National Wildlife Refuges, Jefferson, Island, San Juan...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-18

..., Washington Maritime National Wildlife Refuge Complex, 715 Holgerson Drive, Sequim, WA 98382. FOR FURTHER...] Protection Island and San Juan Islands National Wildlife Refuges, Jefferson, Island, San Juan, Skagit, and Whatcom Counties, WA AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of availability: draft...

Compact and tunable focusing device for plasma wakefield acceleration

NASA Astrophysics Data System (ADS)

Pompili, R.; Anania, M. P.; Chiadroni, E.; Cianchi, A.; Ferrario, M.; Lollo, V.; Notargiacomo, A.; Picardi, L.; Ronsivalle, C.; Rosenzweig, J. B.; Shpakov, V.; Vannozzi, A.

2018-03-01

Plasma wakefield acceleration, either driven by ultra-short laser pulses or electron bunches, represents one of the most promising techniques able to overcome the limits of conventional RF technology and allows the development of compact accelerators. In the particle beam-driven scenario, ultra-short bunches with tiny spot sizes are required to enhance the accelerating gradient and preserve the emittance and energy spread of the accelerated bunch. To achieve such tight transverse beam sizes, a focusing system with short focal length is mandatory. Here we discuss the development of a compact and tunable system consisting of three small-bore permanent-magnet quadrupoles with 520 T/m field gradient. The device has been designed in view of the plasma acceleration experiments planned at the SPARC_LAB test-facility. Being the field gradient fixed, the focusing is adjusted by tuning the relative position of the three magnets with nanometer resolution. Details about its magnetic design, beam-dynamics simulations, and preliminary results are examined in the paper.

Sustainable dual-use labs: neurovascular interventional capabilities within the cath lab.

PubMed

Lang, Stacey

2012-01-01

The inclusion of neurovascular interventional capabilities within the cath lab setting can be key to optimal utilization of resources, increased staff efficiency, and streamlined operations. When considering an expansion, look beyond the patient population traditionally associated with cardiac cath labs and consider the integration of programs outside cardiac alone--to create a true dual-use lab space. With proper planning, quality dual purpose equipment, appropriately trained staff, capable physicians, and strong leadership, an organization willing to embrace the challenge can build a truly extraordinary service.

Lab at Home: Hardware Kits for a Digital Design Lab

ERIC Educational Resources Information Center

Oliver, J. P.; Haim, F.

2009-01-01

An innovative laboratory methodology for an introductory digital design course is presented. Instead of having traditional lab experiences, where students have to come to school classrooms, a "lab at home" concept is proposed. Students perform real experiments in their own homes, using hardware kits specially developed for this purpose. They…

Spectroscopic measurements of plasma emission light for plasma-based acceleration experiments

NASA Astrophysics Data System (ADS)

Filippi, F.; Anania, M. P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Ferrario, M.; Mostacci, A.; Palumbo, L.; Zigler, A.

2016-09-01

Advanced particle accelerators are based on the excitation of large amplitude plasma waves driven by either electron or laser beams. Future experiments scheduled at the SPARC_LAB test facility aim to demonstrate the acceleration of high brightness electron beams through the so-called resonant Plasma Wakefield Acceleration scheme in which a train of electron bunches (drivers) resonantly excites wakefields into a preformed hydrogen plasma; the last bunch (witness) injected at the proper accelerating phase gains energy from the wake. The quality of the accelerated beam depends strongly on plasma density and its distribution along the acceleration length. The measurements of plasma density of the order of 1016-1017 cm-3 can be performed with spectroscopic measurements of the plasma-emitted light. The measured density distribution for hydrogen filled capillary discharge with both Balmer alpha and Balmer beta lines and shot-to-shot variation are here reported.

76 FR 19781 - Protection Island and San Juan Islands National Wildlife Refuges, Jefferson, San Juan, Skagit...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-08

...., Lopez Island, WA 98261. North Olympic Public Library..... 630 N. Sequim Ave., 360-683-1161 Sequim, WA...] Protection Island and San Juan Islands National Wildlife Refuges, Jefferson, San Juan, Skagit, Island, and Whatcom Counties, WA; Final Comprehensive Conservation Plan, Wilderness Stewardship Plan, and Finding of...

LCOGT Imaging Lab

NASA Astrophysics Data System (ADS)

Tufts, Joseph R.; Lobdill, Rich; Haldeman, Benjamin J.; Haynes, Rachel; Hawkins, Eric; Burleson, Ben; Jahng, David

2008-07-01

The Las Cumbres Observatory Global Telescope Network (LCOGT) is an ambitious project to build and operate, within 5 years, a worldwide robotic network of 50 0.4, 1, and 2 m telescopes sharing identical instrumentation and optimized for precision photometry of time-varying sources. The telescopes, instrumentation, and software are all developed in house with two 2 m telescopes already installed. The LCOGT Imaging Lab is responsible for assembly and characterization of the network's cameras and instrumentation. In addition to a fully equipped CNC machine shop, two electronics labs, and a future optics lab, the Imaging Lab is designed from the ground up to be a superb environment for bare detectors, precision filters, and assembled instruments. At the heart of the lab is an ISO class 5 cleanroom with full ionization. Surrounding this, the class 7 main lab houses equipment for detector characterization including QE and CTE, and equipment for measuring transmission and reflection of optics. Although the first science cameras installed, two TEC cooled e2v 42-40 deep depletion based units and two CryoTiger cooled Fairchild Imaging CCD486-BI based units, are from outside manufacturers, their 18 position filter wheels and the remainder of the network's science cameras, controllers, and instrumentation will be built in house. Currently being designed, the first generation LCOGT cameras for the network's 1 m telescopes use existing CCD486-BI devices and an in-house controller. Additionally, the controller uses digital signal processing to optimize readout noise vs. speed, and all instrumentation uses embedded microprocessors for communication over ethernet.

Inexpensive DAQ based physics labs

NASA Astrophysics Data System (ADS)

Lewis, Benjamin; Clark, Shane

2015-11-01

Quality Data Acquisition (DAQ) based physics labs can be designed using microcontrollers and very low cost sensors with minimal lab equipment. A prototype device with several sensors and documentation for a number of DAQ-based labs is showcased. The device connects to a computer through Bluetooth and uses a simple interface to control the DAQ and display real time graphs, storing the data in .txt and .xls formats. A full device including a larger number of sensors combined with software interface and detailed documentation would provide a high quality physics lab education for minimal cost, for instance in high schools lacking lab equipment or students taking online classes. An entire semester’s lab course could be conducted using a single device with a manufacturing cost of under $20.

Effects of acceleration rate on Rayleigh-Taylor instability in elastic-plastic materials

NASA Astrophysics Data System (ADS)

Banerjee, Arindam; Polavarapu, Rinosh

2016-11-01

The effect of acceleration rate in the elastic-plastic transition stage of Rayleigh-Taylor instability in an accelerated non-Newtonian material is investigated experimentally using a rotating wheel experiment. A non-Newtonian material (mayonnaise) was accelerated at different rates by varying the angular acceleration of a rotating wheel and growth patterns of single mode perturbations with different combinations of amplitude and wavelength were analyzed. Experiments were run at two different acceleration rates to compare with experiments presented in prior years at APS DFD meetings and the peak amplitude responses are captured using a high-speed camera. Similar to the instability acceleration, the elastic-plastic transition acceleration is found to be increasing with increase in acceleration rate for a given amplitude and wavelength. The experimental results will be compared to various analytical strength models and prior experimental studies using Newtonian fluids. Authors acknowledge funding support from Los Alamos National Lab subcontract(370333) and DOE-SSAA Grant (DE-NA0001975).

MatLab Script and Functional Programming

NASA Technical Reports Server (NTRS)

Shaykhian, Gholam Ali

2007-01-01

MatLab Script and Functional Programming: MatLab is one of the most widely used very high level programming languages for scientific and engineering computations. It is very user-friendly and needs practically no formal programming knowledge. Presented here are MatLab programming aspects and not just the MatLab commands for scientists and engineers who do not have formal programming training and also have no significant time to spare for learning programming to solve their real world problems. Specifically provided are programs for visualization. The MatLab seminar covers the functional and script programming aspect of MatLab language. Specific expectations are: a) Recognize MatLab commands, script and function. b) Create, and run a MatLab function. c) Read, recognize, and describe MatLab syntax. d) Recognize decisions, loops and matrix operators. e) Evaluate scope among multiple files, and multiple functions within a file. f) Declare, define and use scalar variables, vectors and matrices.

Experiences with lab-centric instruction

NASA Astrophysics Data System (ADS)

Titterton, Nathaniel; Lewis, Colleen M.; Clancy, Michael J.

2010-06-01

Lab-centric instruction emphasizes supervised, hands-on activities by substituting lab for lecture time. It combines a multitude of pedagogical techniques into the format of an extended, structured closed lab. We discuss the range of benefits for students, including increased staff interaction, frequent and varied self-assessments, integrated collaborative activities, and a systematic sequence of activities that gradually increases in difficulty. Instructors also benefit from a deeper window into student progress and understanding. We follow with discussion of our experiences in courses at U.C. Berkeley, and using data from some of these investigate the effects of lab-centric instruction on student learning, procrastination, and course pacing. We observe that the lab-centric format helped students on exams but hurt them on extended programming assignments, counter to our hypothesis. Additionally, we see no difference in self-ratings of procrastination and limited differences in ratings of course pace. We do find evidence that the students who choose to attend lab-centric courses are different in several important ways from students who choose to attend the same course in a non-lab-centric format.

EarthLabs: A National Model for Earth Science Lab Courses

NASA Astrophysics Data System (ADS)

McDaris, J. R.; Dahlman, L.; Barstow, D.

2008-12-01

As a response to the need for more rigorous, inquiry-based high school Earth science courses, a coalition of scientists, educators, and five states have created EarthLabs, a set of pilot modules that can serve as a national model for lab-based science courses. The content of EarthLabs chapters focuses on Earth system science and environmental literacy and conforms to the National Science Education Standards as well as the states' curriculum frameworks. The effort is funded by NOAA's Environmental Literacy program. The pilot modules present activities on Corals, Drought, Fisheries, and Hurricanes. The Fisheries and Hurricanes units were reviewed and field-tested by educators in Texas and Arizona. The feedback from this evaluation led to revisions of these units and guided development of the Corals and Drought chapters. Each module consists of activities that use online data sets, satellite imagery, web-based readings, and hands-on laboratory experiments. The project comprises two separate websites, one for the instructor and one for students. The instructor's site contains the pedagogical underpinnings for each lab including teaching materials, assessment strategies, and the alignment of activities with state and national science standards. The student site provides access to all materials that students need to complete the activities or, in the case of the hands-on labs, where they access additional information to help extend their learning. There are also formative and summative questions embedded in the student webpages to help scaffold learning through the activities.

Improving the Quality of Lab Reports by Using Them as Lab Instructions

NASA Astrophysics Data System (ADS)

Haagen-Schuetzenhoefer, Claudia

2012-10-01

Lab exercises are quite popular in teaching science. Teachers have numerous goals in mind when teaching science laboratories. Nevertheless, empirical research draws a heterogeneous picture of the benefits of lab work. Research has shown that it does not necessarily contribute to the enhancement of practical abilities or content knowledge. Lab activities are frequently based on recipe-like, step-by-step instructions ("cookbook style"), which do not motivate students to engage cognitively. Consequently, students put the emphasis on "task completion" or "manipulating equipment."2

Plasma production for electron acceleration by resonant plasma wave

NASA Astrophysics Data System (ADS)

Anania, M. P.; Biagioni, A.; Chiadroni, E.; Cianchi, A.; Croia, M.; Curcio, A.; Di Giovenale, D.; Di Pirro, G. P.; Filippi, F.; Ghigo, A.; Lollo, V.; Pella, S.; Pompili, R.; Romeo, S.; Ferrario, M.

2016-09-01

Plasma wakefield acceleration is the most promising acceleration technique known nowadays, able to provide very high accelerating fields (10-100 GV/m), enabling acceleration of electrons to GeV energy in few centimeter. However, the quality of the electron bunches accelerated with this technique is still not comparable with that of conventional accelerators (large energy spread, low repetition rate, and large emittance); radiofrequency-based accelerators, in fact, are limited in accelerating field (10-100 MV/m) requiring therefore hundred of meters of distances to reach the GeV energies, but can provide very bright electron bunches. To combine high brightness electron bunches from conventional accelerators and high accelerating fields reachable with plasmas could be a good compromise allowing to further accelerate high brightness electron bunches coming from LINAC while preserving electron beam quality. Following the idea of plasma wave resonant excitation driven by a train of short bunches, we have started to study the requirements in terms of plasma for SPARC_LAB (Ferrario et al., 2013 [1]). In particular here we focus on hydrogen plasma discharge, and in particular on the theoretical and numerical estimates of the ionization process which are very useful to design the discharge circuit and to evaluate the current needed to be supplied to the gas in order to have full ionization. Eventually, the current supplied to the gas simulated will be compared to that measured experimentally.

Stereotactic radiosurgery for trigeminal neuralgia utilizing the BrainLAB Novalis system.

PubMed

Zahra, Hadi; Teh, Bin S; Paulino, Arnold C; Yoshor, Daniel; Trask, Todd; Baskin, David; Butler, E Brian

2009-12-01

Stereotactic radiosurgery (SRS) is one of the least invasive treatments for trigeminal neuralgia (TN). To date, most reports have been about Cobalt-based treatments (i.e., Gamma Knife) with limited data on image-guided stereotactic linear accelerator treatments. We describe our initial experience of using BrainLAB Novalis stereotactic system for the radiosurgical treatment of TN. A total of 20 patients were treated between July 2004 and February 2007. Each SRS procedure was performed using the BrainLAB Novalis System. Thin cuts MRI images of 1.5 mm thickness were acquired and fused with the simulation CT of each patient. Majority of the patients received a maximum dose of 90 Gy. The median brainstem dose to 1.0 cc and 0.1 cc was 2.3 Gy and 13.5 Gy, respectively. In addition, specially acquired three-dimensional fast imaging sequence employing steady-state acquisition (FIESTA) MRI was utilized to improve target delineation of the trigeminal proximal nerve root entry zone. Barrow Neurological Index (BNI) pain scale for TN was used for assessing treatment outcome. At a median follow-up time of 14.2 months, 19 patients (95%) reported at least some improvement in pain. Eight (40%) patients were completely pain-free and stopped all medications (BNI Grade I) while another 2 (10%) patients also stopped medications but reported occasional pain (BNI Grade II). Another 2 (10%) patients reported no pain and 7 (35%) patients only occasional pain while continuing medications, BNI Grade IIIA and IIIB, respectively. Median time to pain control was 8.5 days (range: 1-70 days). No patient reported severe pain, worsening pain or any pain not controlled on their previously taken medication. Intermittent or persistent facial numbness following treatments occurred in 35% of patients. No other complications were reported. Stereotactic radiosurgery using the BrainLAB Novalis system is a safe and effective treatment for TN. This information is important as more centers are obtaining image

Development of a Hampton University Program for Novel Breast Cancer Imaging and Therapy Research

DTIC Science & Technology

2015-06-01

student ( Nanda Karthik) involved…. Should be able to give you some text!]. Aim 2 Develop and test a practical method for application of a magnetic field ...a Department of Energy (DOE) nuclear physics research facility operated by Jefferson Science Associates LLC. Jefferson Lab resources for this...minimally affected by breast density because of the higher energy photons of 99mTc. In a recent study that included patients who had inconclusive

Lab Report Blues

ERIC Educational Resources Information Center

Diaz, Andrew

2004-01-01

For middle school students, writing a formal lab report can be challenging. For middle level teachers, reading students lab reports can be overwhelming. After grading report after report with incomplete procedures, incorrect graphs, and missing conclusions, the author's frustration level was at an all-time high. Ready to try anything, he thought,…

Reforming Cookbook Labs

ERIC Educational Resources Information Center

Peters, Erin

2005-01-01

Deconstructing cookbook labs to require the students to be more thoughtful could break down perceived teacher barriers to inquiry learning. Simple steps that remove or disrupt the direct transfer of step-by-step procedures in cookbook labs make students think more critically about their process. Through trials in the author's middle school…

Silent reminders: geologic wonders of the George Washington and Jefferson National Forests

USGS Publications Warehouse

,; ,

2001-01-01

The iron industry played a vital role in the industrialization of the United States and in the development of the U.S. economy and society. Much of the early history of the iron industry took place in Virginia. The remains of 11 iron furnaces and nearby mines in the George Washington and Jefferson National Forests in Virginia and West Virginia are silent reminders of a time when iron mines and furnaces operated along a belt that extended through the Appalachian Mountains from New York State to Alabama.

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

Federal Register 2010, 2011, 2012, 2013, 2014

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...

Accelerating Venture Creation and Building on Mutual Strengths in Experimental Business Labs

ERIC Educational Resources Information Center

Curley, Martin G.; Formica, Piero

2010-01-01

This paper articulates the opportunity of using an experimental business laboratory approach as a means of accelerating the creation, incubation and testing of new venture ideas. Such a strategy leads to the establishment of a micro-ecosystem of aspiring entrepreneurs and others in a business laboratory environment. The goal is to create a mini…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weisenberger, Andrew G.; Kross, Brian J.; Lee, Seung Joo

The ability to detect the emissions of radioactive isotopes through radioactive decay (e.g. beta particles, x-rays and gamma-rays) has been used for over 80 years as a tracer method for studying natural phenomena. More recently a positron emitting radioisotope of carbon: {sup 11}C has been utilized as a {sup 11}CO{sub 2} tracer for plant ecophysiology research. Because of its ease of incorporation into the plant via photosynthesis, the {sup 11}CO{sub 2} radiotracer is a powerful tool for use in plant biology research. Positron emission tomography (PET) imaging has been used to study carbon transport in live plants using {sup 11}CO{submore » 2}. Presently there are several groups developing and using new PET instrumentation for plant based studies. Thomas Jefferson National Accelerator Facility (Jefferson Lab) in collaboration with the Duke University Phytotron and the Triangle Universities Nuclear Laboratory (TUNL) is involved in PET detector development for plant imaging utilizing technologies developed for nuclear physics research. The latest developments of the use of a LYSO scintillator based PET detector system for {sup 11}CO{sub 2} tracer studies in plants will be briefly outlined.« less

Cross Sections for the Exclusive Photon Electroproduction on the Proton and Generalized Parton Distributions.

PubMed

Jo, H S; Girod, F X; Avakian, H; Burkert, V D; Garçon, M; Guidal, M; Kubarovsky, V; Niccolai, S; Stoler, P; Adhikari, K P; Adikaram, D; Amaryan, M J; Anderson, M D; Anefalos Pereira, S; Ball, J; Baltzell, N A; Battaglieri, M; Batourine, V; Bedlinskiy, I; Biselli, A S; Boiarinov, S; Briscoe, W J; Brooks, W K; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Colaneri, 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; Dupre, R; Alaoui, A El; Fassi, L El; Elouadrhiri, L; Fedotov, G; Fegan, S; Filippi, A; Fleming, J A; Garillon, B; Gevorgyan, N; Ghandilyan, Y; Gilfoyle, G P; Giovanetti, K L; Goetz, J T; Golovatch, E; Gothe, R W; Griffioen, K A; Guegan, B; Guler, N; Guo, L; Hafidi, K; Hakobyan, H; Harrison, N; Hattawy, M; Hicks, K; Hirlinger Saylor, N; Ho, D; Holtrop, M; Hughes, S M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Jenkins, D; Joo, K; Joosten, S; Keller, D; Khachatryan, G; Khandaker, M; Kim, A; Kim, W; Klein, A; Klein, F J; Kuhn, S E; Kuleshov, S V; Lenisa, P; Livingston, K; Lu, H Y; MacGregor, I J D; McKinnon, B; Meziani, Z E; Mirazita, M; Mokeev, V; Montgomery, R A; Moutarde, H; Movsisyan, A; Munevar, E; Munoz Camacho, C; Nadel-Turonski, P; Net, L A; Niculescu, G; Osipenko, M; Ostrovidov, A I; Paolone, M; Park, K; Pasyuk, E; Phillips, J J; Pisano, S; Pogorelko, O; Price, J W; Procureur, S; Prok, Y; Puckett, A J R; Raue, B A; Ripani, M; Rizzo, A; Rosner, G; Rossi, P; Roy, P; Sabatié, F; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Simonyan, A; Skorodumina, Iu; Smith, G D; Sokhan, D; Sparveris, N; Stepanyan, S; Strakovsky, I I; Strauch, S; Sytnik, V; Tian, Ye; Tkachenko, S; Ungaro, M; Voskanyan, H; Voutier, E; Walford, N K; Watts, D P; Wei, X; Weinstein, L B; Wood, M H; Zachariou, N; Zana, L; Zhang, J; Zhao, Z W; Zonta, I

2015-11-20

Unpolarized and beam-polarized fourfold cross sections (d^{4}σ/dQ^{2}dx_{B}dtdϕ) for the ep→e^{'}p^{'}γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q^{2},x_{B},t) bins over the widest phase space ever explored in the valence-quark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H, expected to be the dominant contributor to these observables. Through a leading-twist extraction of Compton form factors, these results support the model predictions of a larger nucleon size at lower quark-momentum fraction x_{B}.

Search for hybrid baryons with CLAS12 experimental setup

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lanza, Lucille

It is crucial to study the meson electroproduction in the kinematic region dominated by the formation of resonances. CLAS12 setup in Hall B at Jefferson Lab is particularly suitable for this task, since it is able to detect scattered electrons at low polar angles thanks to the Forward Tagger (FT) component. The process that we propose to study is ep → e'K +Λ, where the electron beam will be provided by the CEBAF accelerator with energies of 6.6, 8.8, and 11 GeV. This thesis work describes the setup and calibration of the FT calorimeter and the studies related to themore » search of hybrid baryons through the measurement of the K + Λ electroproduction cross section.« less

Cryomdoule Test Stand Reduced-Magnetic Support Design at Fermilab

DOE Office of Scientific and Technical Information (OSTI.GOV)

McGee, Mike; Chandrasekaran, Saravan Kumar; Crawford, Anthony

2016-06-01

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 devices will be tested at Fermilab's Cryomodule Test Facility (CMTF) within the Cryomodule Test Stand (CMTS-1) cave. The problem of magnetic pollution became one of major issues during design stage of the LCLS-II cryomodule as the average quality factor of the accelerating cavities is specified to be 2.7 x 10¹⁰. One of the possible ways to mitigate the effect of stray magnetic fields and tomore » keep it below the goal of 5 mGauss involves the application of low permeable materials. Initial permeability and magnetic measurement studies regarding the use of 316L stainless steel material indicated that cold work (machining) and heat affected zones from welding would be acceptable.« less

Status of chemistry lab safety in Nepal.

PubMed

Kandel, Krishna Prasad; Neupane, Bhanu Bhakta; Giri, Basant

2017-01-01

Chemistry labs can become a dangerous environment for students as the lab exercises involve hazardous chemicals, glassware, and equipment. Approximately one hundred thousand students take chemistry laboratory classes annually in Nepal. We conducted a survey on chemical lab safety issues across Nepal. In this paper, we assess the safety policy and equipment, protocols and procedures followed, and waste disposal in chemistry teaching labs. Significant population of the respondents believed that there is no monitoring of the lab safety in their lab (p<0.001). Even though many labs do not allow food and beverages inside lab and have first aid kits, they lack some basic safety equipment. There is no institutional mechanism to dispose lab waste and chemical waste is disposed haphazardly. Majority of the respondents believed that the safety training should be a part of educational training (p = 0.001) and they would benefit from short course and/or workshop on lab safety (p<0.001).

Status of chemistry lab safety in Nepal

PubMed Central

Kandel, Krishna Prasad; Neupane, Bhanu Bhakta

2017-01-01

Chemistry labs can become a dangerous environment for students as the lab exercises involve hazardous chemicals, glassware, and equipment. Approximately one hundred thousand students take chemistry laboratory classes annually in Nepal. We conducted a survey on chemical lab safety issues across Nepal. In this paper, we assess the safety policy and equipment, protocols and procedures followed, and waste disposal in chemistry teaching labs. Significant population of the respondents believed that there is no monitoring of the lab safety in their lab (p<0.001). Even though many labs do not allow food and beverages inside lab and have first aid kits, they lack some basic safety equipment. There is no institutional mechanism to dispose lab waste and chemical waste is disposed haphazardly. Majority of the respondents believed that the safety training should be a part of educational training (p = 0.001) and they would benefit from short course and/or workshop on lab safety (p<0.001). PMID:28644869

Particle Accelerator Focus Automation

NASA Astrophysics Data System (ADS)

Lopes, José; Rocha, Jorge; Redondo, Luís; Cruz, João

2017-08-01

The Laboratório de Aceleradores e Tecnologias de Radiação (LATR) at the Campus Tecnológico e Nuclear, of Instituto Superior Técnico (IST) has a horizontal electrostatic particle accelerator based on the Van de Graaff machine which is used for research in the area of material characterization. This machine produces alfa (He+) and proton (H+) beams of some μA currents up to 2 MeV/q energies. Beam focusing is obtained using a cylindrical lens of the Einzel type, assembled near the high voltage terminal. This paper describes the developed system that automatically focuses the ion beam, using a personal computer running the LabVIEW software, a multifunction input/output board and signal conditioning circuits. The focusing procedure consists of a scanning method to find the lens bias voltage which maximizes the beam current measured on a beam stopper target, which is used as feedback for the scanning cycle. This system, as part of a wider start up and shut down automation system built for this particle accelerator, brings great advantages to the operation of the accelerator by turning it faster and easier to operate, requiring less human presence, and adding the possibility of total remote control in safe conditions.

Measurement of the beam asymmetry Σ and the target asymmetry T in the photoproduction of ω mesons off the proton using CLAS at Jefferson Laboratory

NASA Astrophysics Data System (ADS)

Roy, P.; Akbar, Z.; Park, S.; Crede, V.; Anisovich, A. V.; Denisenko, I.; Klempt, E.; Nikonov, V. A.; Sarantsev, A. V.; Adhikari, K. P.; Adhikari, S.; Anefalos Pereira, S.; Ball, J.; Balossino, I.; Bashkanov, M.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brock, J.; Brooks, W. K.; Burkert, V. D.; Carlin, C.; Carman, D. S.; Celentano, A.; Charles, G.; Chetry, T.; Ciullo, G.; Clary, B. A.; Cole, P. L.; Contalbrigo, M.; D'Angelo, A.; Dashyan, N.; De Vita, R.; Deur, A.; Djalali, C.; Dugger, M.; Dupre, R.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Filippi, A.; Fradi, A.; Gavalian, G.; Gevorgyan, N.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Hattawy, M.; Hicks, K.; Holtrop, M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Joo, K.; Joosten, S.; Keith, C. D.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McCracken, M. E.; McKinnon, B.; Meekins, D. G.; Meyer, C. A.; Meziani, Z. E.; Mineeva, T.; Mokeev, V.; Montgomery, R. A.; Movsisyan, A.; Munoz Camacho, C.; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Phelps, E.; Phelps, W.; Pierce, J. J.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Protopopescu, D.; Raue, B. A.; Ripani, M.; Riser, D.; Ritchie, B. G.; Rizzo, A.; Rosner, G.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sober, D. I.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tan, J. A.; Torayev, B.; Ungaro, M.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Wood, M. H.; Zachariou, N.; Zhang, J.; Zhao, Z. W.; CLAS Collaboration

2018-05-01

The photoproduction of ω mesons off the proton has been studied in the reaction γ p →p ω using the CEBAF Large Acceptance Spectrometer (CLAS) and the frozen-spin target in Hall B at the Thomas Jefferson National Accelerator Facility. For the first time, the target asymmetry T has been measured in photoproduction from the decay ω →π+π-π0 , using a transversely polarized target with energies ranging from just above the reaction threshold up to 2.8 GeV. Significant nonzero values are observed for these asymmetries, reaching about 30-40% in the third-resonance region. New measurements for the photon-beam asymmetry Σ are also presented, which agree well with previous CLAS results and extend the world database up to 2.1 GeV. These data and additional ω photoproduction observables from CLAS were included in a partial-wave analysis within the Bonn-Gatchina framework. Significant contributions from s -channel resonance production were found in addition to t -channel exchange processes.

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

PubMed

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.

Mathematics for the Eighties: A Study of Two Effective Math Programs.

ERIC Educational Resources Information Center

O'Connor, Patrick J.

1985-01-01

This bulletin describes two exemplary mathematics programs in Oregon: the Math Lab at Mountain View Junior High School in Beaverton and the Academy Math Program at Jefferson High School in northeastern Portland. The Math Lab at Mountain View is a weekly supplemental unit that is integrated into general math and pre-algebra courses for seventh and…

Transgressive variation for yield components and dynamic traits in Jefferson (Oryza sativa) x O. rufipogon introgression lines

USDA-ARS?s Scientific Manuscript database

Alleles from wild progenitors of crops can be a source of transgressive variation in modern cultivars. Introgressions from the Oryza rufipogon donor (IRGC104591) in an O. sativa tropical japonica cultivar (Jefferson) were shown to confer a yield advantage in multi-location field trials. Yield loci...

SenseLab

PubMed Central

Crasto, Chiquito J.; Marenco, Luis N.; Liu, Nian; Morse, Thomas M.; Cheung, Kei-Hoi; Lai, Peter C.; Bahl, Gautam; Masiar, Peter; Lam, Hugo Y.K.; Lim, Ernest; Chen, Huajin; Nadkarni, Prakash; Migliore, Michele; Miller, Perry L.; Shepherd, Gordon M.

2009-01-01

This article presents the latest developments in neuroscience information dissemination through the SenseLab suite of databases: NeuronDB, CellPropDB, ORDB, OdorDB, OdorMapDB, ModelDB and BrainPharm. These databases include information related to: (i) neuronal membrane properties and neuronal models, and (ii) genetics, genomics, proteomics and imaging studies of the olfactory system. We describe here: the new features for each database, the evolution of SenseLab’s unifying database architecture and instances of SenseLab database interoperation with other neuroscience online resources. PMID:17510162

Integrating Robotic Observatories into Astronomy Labs

NASA Astrophysics Data System (ADS)

Ruch, Gerald T.

2015-01-01

The University of St. Thomas (UST) and a consortium of five local schools is using the UST Robotic Observatory, housing a 17' telescope, to develop labs and image processing tools that allow easy integration of observational labs into existing introductory astronomy curriculum. Our lab design removes the burden of equipment ownership by sharing access to a common resource and removes the burden of data processing by automating processing tasks that are not relevant to the learning objectives.Each laboratory exercise takes place over two lab periods. During period one, students design and submit observation requests via the lab website. Between periods, the telescope automatically acquires the data and our image processing pipeline produces data ready for student analysis. During period two, the students retrieve their data from the website and perform the analysis. The first lab, 'Weighing Jupiter,' was successfully implemented at UST and several of our partner schools. We are currently developing a second lab to measure the age of and distance to a globular cluster.

Spin Observables in h Meson Photoproduction on the Proton

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tucker, Ross

2016-05-01

A series of experiments using a polarized beam incident on a polarized frozen spin target (FROST) was conducted at Jefferson Lab in 2010. Results presented here were taken during the second running period with the FROST target using the CEBAF Large Acceptance Spectrometer (CLAS) detector at Jefferson Lab, which used transversely-polarized protons in a butanol target and a circularly-polarized incident tagged photon beam with energies between 0:62 and 2:93 GeV. Data are presented for the F and T polarization observables for n meson photoproduction on the proton from W = 1:55 GeV to 1:80 GeV. The data presented here willmore » improve the world database and refine theoretical approaches of nucleon structure.« less

Iterative Monte Carlo analysis of spin-dependent parton distributions

DOE PAGES

Sato, Nobuo; Melnitchouk, Wally; Kuhn, Sebastian E.; ...

2016-04-05

We present a comprehensive new global QCD analysis of polarized inclusive deep-inelastic scattering, including the latest high-precision data on longitudinal and transverse polarization asymmetries from Jefferson Lab and elsewhere. The analysis is performed using a new iterative Monte Carlo fitting technique which generates stable fits to polarized parton distribution functions (PDFs) with statistically rigorous uncertainties. Inclusion of the Jefferson Lab data leads to a reduction in the PDF errors for the valence and sea quarks, as well as in the gluon polarization uncertainty at x ≳ 0.1. Furthermore, the study also provides the first determination of the flavor-separated twist-3 PDFsmore » and the d 2 moment of the nucleon within a global PDF analysis.« less

A Comparison of Jefferson Medical College Graduates Who Chose Emergency Medicine with Those Who Chose Other Specialties.

ERIC Educational Resources Information Center

Xu, Gang; Veloski, J. Jon

1991-01-01

Data on 53 Jefferson Medical College (Pennsylvania) graduates specializing in emergency medicine (EM) found they had the highest senior year debt and expected the highest income among nonsurgeons, compared favorably in academic performance and examination scores and were very willing to treat low-income patients. Implications are discussed.…

Improving the Quality of Lab Reports by Using Them as Lab Instructions

ERIC Educational Resources Information Center

Haagen-Schuetzenhoefer, Claudia

2012-01-01

Lab exercises are quite popular in teaching science. Teachers have numerous goals in mind when teaching science laboratories. Nevertheless, empirical research draws a heterogeneous picture of the benefits of lab work. Research has shown that it does not necessarily contribute to the enhancement of practical abilities or content knowledge. Lab…

Computational Labs Using VPython Complement Conventional Labs in Online and Regular Physics Classes

NASA Astrophysics Data System (ADS)

Bachlechner, Martina E.

2009-03-01

Fairmont State University has developed online physics classes for the high-school teaching certificate based on the text book Matter and Interaction by Chabay and Sherwood. This lead to using computational VPython labs also in the traditional class room setting to complement conventional labs. The computational modeling process has proven to provide an excellent basis for the subsequent conventional lab and allows for a concrete experience of the difference between behavior according to a model and realistic behavior. Observations in the regular class room setting feed back into the development of the online classes.

A Checklist of Common Plants of the Appalachian Trail in the Jefferson National Forest, Virginia

Treesearch

Arnold Krochmal; Connie Krochmal

1981-01-01

This Note lists the plants that a hiker is likely to notice on the Appalachian Trail in the Jefferson National Forest, Virginia. The list is one of the results of an inventory of plant life along the Trail as it passes through Southern National Forests. Only plants that were conspicuous because of their size, large population, or leaf or flower color are listed. Fungi...

Spaceport Processing System Development Lab

NASA Technical Reports Server (NTRS)

Dorsey, Michael

2013-01-01

The Spaceport Processing System Development Lab (SPSDL), developed and maintained by the Systems Hardware and Engineering Branch (NE-C4), is a development lab with its own private/restricted networks. A private/restricted network is a network with restricted or no communication with other networks. This allows users from different groups to work on their own projects in their own configured environment without interfering with others utilizing their resources in the lab. The different networks being used in the lab have no way to talk with each other due to the way they are configured, so how a user configures his software, operating system, or the equipment doesn't interfere or carry over on any of the other networks in the lab. The SPSDL is available for any project in KSC that is in need of a lab environment. My job in the SPSDL was to assist in maintaining the lab to make sure it's accessible for users. This includes, but is not limited to, making sure the computers in the lab are properly running and patched with updated hardware/software. In addition to this, I also was to assist users who had issues in utilizing the resources in the lab, which may include helping to configure a restricted network for their own environment. All of this was to ensure workers were able to use the SPSDL to work on their projects without difficulty which would in turn, benefit the work done throughout KSC. When I wasn't working in the SPSDL, I would instead help other coworkers with smaller tasks which included, but wasn't limited to, the proper disposal, moving of, or search for essential equipment. I also, during the free time I had, used NASA's resources to increase my knowledge and skills in a variety of subjects related to my major as a computer engineer, particularly in UNIX, Networking, and Embedded Systems.

On the g/2 Acceleration of a Pulse in a Vertical Chain

ERIC Educational Resources Information Center

Foster, Theodore; van Wyngaarden, Willem; Cary, Arthur; Mottmann, John

2013-01-01

We have frequently enhanced our department's laboratory experiment involving standing transverse waves in a taut horizontal cord. In addition to the standard experiment, students in these labs investigate the surprising concept that the acceleration of a pulse in a chain hanging vertically is a constant and is equal to half the acceleration…

Effect of low temperature baking on the RF properties of niobium superconducting cavities for particle accelerators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gianluigi Ciovati

Radio-frequency superconducting (SRF) cavities are widely used to accelerate a charged particle beam in particle accelerators. The performance of SRF cavities made of bulk niobium has significantly improved over the last ten years and is approaching the theoretical limit for niobium. Nevertheless, RF tests of niobium cavities are still showing some ''anomalous'' losses that require a better understanding in order to reliably obtain better performance. These losses are characterized by a marked dependence of the surface resistance on the surface electromagnetic field and can be detected by measuring the quality factor of the resonator as a function of the peakmore » surface field. A low temperature (100 C-150 C) ''in situ'' bake under ultra-high vacuum has been successfully applied as final preparation of niobium RF cavities by several laboratories over the last few years. The benefits reported consist mainly of an improvement of the cavity quality factor at low field and a recovery from ''anomalous'' losses (so-called ''Q-drop'') without field emission at higher field. A series of experiments with a CEBAF single-cell cavity have been carried out at Jefferson Lab to carefully investigate the effect of baking at progressively higher temperatures for a fixed time on all the relevant material parameters. Measurements of the cavity quality factor in the temperature range 1.37 K-280 K and resonant frequency shift between 6 K-9.3 K provide information about the surface resistance, energy gap, penetration depth and mean free path. The experimental data have been analyzed with the complete BCS theory of superconductivity. The hydrogen content of small niobium samples inserted in the cavity during its surface preparation was analyzed with Nuclear Reaction Analysis (NRA). The single-cell cavity has been tested at three different temperatures before and after baking to gain some insight on thermal conductivity and Kapitza resistance and the data are compared with different

Simulation prediction and experiment setup of vacuum laser acceleration at Brookhaven National Lab-Accelerator Test Facility

NASA Astrophysics Data System (ADS)

Shao, L.; Cline, D.; Ding, X.; Ho, Y. K.; Kong, Q.; Xu, J. J.; Pogorelsky, I.; Yakimenko, V.; Kusche, K.

2013-02-01

This paper presents the pre-experiment plan and prediction of the first stage of vacuum laser acceleration (VLA) collaborating by UCLA, Fudan University and ATF-BNL. This first stage experiment is a proof-of-principle to support our previously posted novel VLA theory. Simulations show that based on ATF's current experimental conditions the electron beam with initial energy of 15 MeV can get net energy gain from an intense CO2 laser beam. The difference in electron beam energy spread is observable by the ATF beam line diagnostics system. Further, this energy spread expansion effect increases along with an increase in laser intensity. The proposal has been approved by the ATF committee and the experiment will be our next project.

GeneLab: Open Science For Exploration

NASA Technical Reports Server (NTRS)

Galazka, Jonathan

2018-01-01

The NASA GeneLab project capitalizes on multi-omic technologies to maximize the return on spaceflight experiments. The GeneLab project houses spaceflight and spaceflight-relevant multi-omics data in a publicly accessible data commons, and collaborates with NASA-funded principal investigators to maximize the omics data from spaceflight and spaceflight-relevant experiments. I will discuss the current status of GeneLab and give specific examples of how the GeneLab data system has been used to gain insight into how biology responds to spaceflight conditions.

LabVIEW-based control and acquisition system for the dosimetric characterization of a silicon strip detector.

PubMed

Ovejero, M C; Pérez Vega-Leal, A; Gallardo, M I; Espino, J M; Selva, A; Cortés-Giraldo, M A; Arráns, R

2017-02-01

The aim of this work is to present a new data acquisition, control, and analysis software system written in LabVIEW. This system has been designed to obtain the dosimetry of a silicon strip detector in polyethylene. It allows the full automation of the experiments and data analysis required for the dosimetric characterization of silicon detectors. It becomes a useful tool that can be applied in the daily routine check of a beam accelerator.

A Museum Learning Lab

ERIC Educational Resources Information Center

Vandiver, Kathleen M.; Bijur, Jon Markowitz; Epstein, Ari W.; Rosenthal, Beryl; Stidsen, Don

2008-01-01

The "Learning Lab: The Cell" exhibit was developed by the Massachusetts Institute of Technology (MIT) Museum and the MIT Center for Environmental Health Sciences (CEHS). Specially designed for middle and high school students, the Learning Lab provides museum visitors of all ages with fascinating insights into how our living cells work. The…

Developing field emission electron sources based on ultrananocrystalline diamond for accelerators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baryshev, Sergey V.; Jing, Chunguang; Qiu, Jiaqi

Radiofrequency (RF) electron guns work by establishing an RF electromagnetic field inside a cavity having conducting walls. Electrons from a cathode are generated in the injector and immediately become accelerated by the RF electric field, and exit the gun as a series of electron bunches. Finding simple solutions for electron injection is a long standing problem. While energies of 30-50 MeV are achievable in linear accelerators (linacs), finding an electron source able to survive under MW electric loads and provide an average current of 1-10 mA is important. Meeting these requirements would open various linac applications for industry. The naturalmore » way to simplify and integrate RF injector architectures with the electron source would be to place the source directly into the RF cavity with no need for additional heaters/lasers. Euclid TechLabs in collaboration with Argonne National Lab are prototyping a family of highly effective field emission electron sources based on a nitrogen-incorporated ultrananocrystalline diamond ((N)UNCD) platform. Determined metrics suggest that our emitters are emissive enough to meet requirements for magnetized cooling at electron-ion colliders, linac-based radioisotope production and X-ray sterilization, and others.« less

Lab-on a-Chip

NASA Technical Reports Server (NTRS)

2003-01-01

Helen Cole, the project manager for the Lab-on-a-Chip Applications Development program, and Lisa Monaco, the project scientist for the program, insert a lab on a chip into the Caliper 42 which is specialized equipment that controls processes on commercial chips to support development of lab-on-a-chip applications. The system has special microscopes and imaging systems, so scientists can process and study different types of fluid, chemical, and medical tests conducted on chips. For example, researchers have examined fluorescent bacteria as it flows through the chips' fluid channels or microfluidic capillaries. Researchers at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama, have been studying how the lab-on-a-chip technology can be used for microbial detection, water quality monitoring, and detecting biosignatures of past or present life on Mars. The Marshall Center team is also collaborating with scientists at other NASA centers and at universities to develop custom chip designs for not only space applications, but for many Earth applications, such as for detecting deadly microbes in heating and air systems. (NASA/MSFC/D.Stoffer)

ERLN Lab Compendium Fact Sheet

EPA Pesticide Factsheets

The Compendium is an online database of environmental testing laboratories nationwide. It enables labs to create profiles of their capabilities, so emergency responders can quickly identify a lab that will meet their support needs.

75 FR 34634 - Special Local Regulation; Swim Across the Sound, Long Island Sound, Port Jefferson, NY to Captain...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-18

...-AA08 Special Local Regulation; Swim Across the Sound, Long Island Sound, Port Jefferson, NY to Captain... Guard is establishing a permanent Special Local Regulation on the navigable waters of Long Island Sound... Sound event. This special local regulation is necessary to provide for the safety of life by protecting...

Analyses of 476 MHz and 952 MHz Crab Cavities for JLAB Electron Ion Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Park, HyeKyoung; Castilla, Alejandro; Delayen, Jean R.

2016-05-01

The Center for Accelerator Science at Old Dominion University has designed, fabricated and successfully tested a crab cavity for Electron Ion Collider at Jefferson Lab (JLEIC) [1]. This proof-of-principle cavity was based on the earlier MEIC design which used 748.5 MHz RF system. The updated JLEIC (called MEIC earlier) design [2] utilizes the components from PEP-II. It results in the change on the bunch repetition rate of stored beam to 476.3 MHz. The ion ring collider will eventually require 952.6 MHz crab cavities. This paper will present the analyses of crab cavities of both 476 MHz and 952 MHz options.more » It compares advantages and disadvantages of the options which provide the JLEIC design team important technical information for a system down selection.« less

Commissioning and Testing the 1970's Era LASS Solenoid Magnet in JLab's Hall D

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ballard, Joshua T.; Biallas, George H.; Brown, G.

2015-06-01

JLab refurbished and reconfigured the LASS1, 1.85m bore Solenoid and installed it as the principal analysis magnet for nuclear physics in the newly constructed, Hall D at Jefferson Lab. The magnet contains four superconducting coils within an iron yoke. The magnet was built in the early1970's at Stanford Linear Accelerator Center and used a second time at Los Alamos National Laboratory. The coils were extensively refurbished and individually tested by JLab. A new Cryogenic Distribution Box provides cryogens and their control valving, current distribution bus, and instrumentation pass-through. A repurposed CTI 2800 refrigerator system and new transfer line complete themore » system. We describe the re-configuration, the process and problems of re-commissioning the magnet and the results of testing the completed magnet.« less

NbTiN Based SIS Multilayer Structures for SRF Applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Valente, Anne-marie; Eremeev, Grigory; Phillips, H

2013-09-01

For the past three decades, bulk niobium has been the material of choice for SRF cavities applications. RF cavity performance is now approaching the theoretical limit for bulk niobium. For further improvement of RF cavity performance for future accelerator projects, Superconductor Insulator - Superconductor (SIS) multilayer structures (as recently proposed by Alex Gurevich) present the theoretical prospect to reach RF performance beyond bulk Nb, using thinly layered higher-Tc superconductors with enhanced Hc1. Jefferson Lab (JLab) is pursuing this approach with the development of NbTiN and AlN based multilayer SIS structures. This paper presents the results on the characteristics of NbTiNmore » films and the first RF measurements on NbTiN-based multilayer structure on thick Nb films.« less

Cross sections for the exclusive photon electroproduction on the proton and Generalized Parton Distributions

DOE PAGES

Jo, Hyon -Suk

2015-11-17

Unpolarized and beam-polarized four-fold cross sectionsmore » $$\\frac{d^4 \\sigma}{dQ^2 dx_B dt d\\phi}$$ for the $$ep\\to e^\\prime p^\\prime \\gamma$$ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 ($$Q^2,x_B,t$$) bins over the widest phase space ever explored in the valence-quark region. Several models of Generalized Parton Distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD $H$, expected to be the dominant contributor to these observables. Thus, through a leading-twist extraction of Compton Form Factors, these results reveal a tomographic image of the nucleon.« less

Cross Sections for the Exclusive Photon Electroproduction on the Proton and Generalized Parton Distributions

NASA Astrophysics Data System (ADS)

Jo, H. S.; Girod, F. X.; Avakian, H.; Burkert, V. D.; Garçon, M.; Guidal, M.; Kubarovsky, V.; Niccolai, S.; Stoler, P.; Adhikari, K. P.; Adikaram, D.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, 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.; Dupre, R.; Alaoui, A. El; Fassi, L. El; Elouadrhiri, L.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J. A.; Garillon, B.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guler, N.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Hattawy, M.; Hicks, K.; Hirlinger Saylor, N.; Ho, D.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Joo, K.; Joosten, S.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; McKinnon, B.; Meziani, Z. E.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moutarde, H.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Park, K.; Pasyuk, E.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Tian, Ye; Tkachenko, S.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

2015-11-01

Unpolarized and beam-polarized fourfold cross sections (d4σ /d Q2d xBd t d ϕ ) for the e p →e'p'γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q2,xB,t ) bins over the widest phase space ever explored in the valence-quark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H , expected to be the dominant contributor to these observables. Through a leading-twist extraction of Compton form factors, these results support the model predictions of a larger nucleon size at lower quark-momentum fraction xB.

Physics Labs with Flavor

ERIC Educational Resources Information Center

Agrest, Mikhail M.

2009-01-01

This paper describes my attempts to look deeper into the so-called "shoot for your grade" labs, started in the '90s, when I began applying my teaching experience in Russia to introductory physics labs at the College of Charleston and other higher education institutions in South Carolina. The term "shoot for your grade" became popular among…

Making Real Virtual Labs

ERIC Educational Resources Information Center

Keller, Harry E.; Keller, Edward E.

2005-01-01

Francis Bacon began defining scientific methodology in the early 17th century, and secondary school science classes began to implement science labs in the mid-19th century. By the early 20th century, leading educators were suggesting that science labs be used to develop scientific thinking habits in young students, and at the beginning of the 21st…

NOT Another Lab Report

ERIC Educational Resources Information Center

Ende, Fred

2012-01-01

Ask students to name the aspects of science class they enjoy most, and working on labs will undoubtedly be mentioned. What often won't be included, however, is writing lab reports. For many students, the process of exploration and data collection is paramount, while the explanation and analysis of findings often takes a backseat. After all, if…

Are Virtual Labs as Effective as Hands-on Labs for Undergraduate Physics? A Comparative Study at Two Major Universities

ERIC Educational Resources Information Center

Darrah, Marjorie; Humbert, Roxann; Finstein, Jeanne; Simon, Marllin; Hopkins, John

2014-01-01

Most physics professors would agree that the lab experiences students have in introductory physics are central to the learning of the concepts in the course. It is also true that these physics labs require time and money for upkeep, not to mention the hours spent setting up and taking down labs. Virtual physics lab experiences can provide an…

The Development of MSFC Usability Lab

NASA Technical Reports Server (NTRS)

Cheng, Yiwei; Richardson, Sally

2010-01-01

This conference poster reviews the development of the usability lab at Marshall Space Flight Center. The purpose of the lab was to integrate a fully functioning usability laboratory to provide a resource for future human factor assessments. and to implement preliminary usability testing on a MSFC website to validate the functionality of the lab.

Microgravity Acceleration Measurement System (MAMS) Flight Configuration Verification and Status

NASA Technical Reports Server (NTRS)

Wagar, William

2000-01-01

The Microgravity Acceleration Measurement System (MAMS) is a precision spaceflight instrument designed to measure and characterize the microgravity environment existing in the US Lab Module of the International Space Station. Both vibratory and quasi-steady triaxial acceleration data are acquired and provided to an Ethernet data link. The MAMS Double Mid-Deck Locker (DMDL) EXPRESS Rack payload meets all the ISS IDD and ICD interface requirements as discussed in the paper which also presents flight configuration illustrations. The overall MAMS sensor and data acquisition performance and verification data are presented in addition to a discussion of the Command and Data Handling features implemented via the ISS, downlink and the GRC Telescience Center displays.

VIEW OF BUILDING 111 LOOKING EAST, NORTHEAST. BUILDING 111, BUILT ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

VIEW OF BUILDING 111 LOOKING EAST, NORTHEAST. BUILDING 111, BUILT IN 1953, WAS ONE OF THE FIRST TEN PERMANENT STRUCTURES ON THE ROCKY FLATS PLANT. THE BUILDING SERVED AS AN ENTRY POINT FOR SITE EMPLOYEES AND HOUSED A PRINT SHOP AND PHOTOGRAPHY LAB. (12/26/52) - Rocky Flats Plant, Offices, Print Shop & Photography Lab, Northwest quad of plant near terminus of Central Avenue, Golden, Jefferson County, CO

Berkeley Lab - Materials Sciences Division

Science.gov Websites

Berkeley Lab Berkeley Lab A-Z Index Phone Book Jobs Search DOE Search MSD Go MSD - Materials Investigators Division Staff Facilities and Centers Staff Jobs Safety Personnel Resources Committees In Case of

Labs That Are a Blast.

ERIC Educational Resources Information Center

Hendrix, Laura

1996-01-01

Presents activities that use a simple homemade apparatus called "the cannon" to demonstrate Newton's Third Law. Reviews the chemistry concepts behind the ignition of the cannon and presents the Momentum Lab and the Projectile Motion Lab. (JRH)

RoboLab and virtual environments

NASA Technical Reports Server (NTRS)

Giarratano, Joseph C.

1994-01-01

A useful adjunct to the manned space station would be a self-contained free-flying laboratory (RoboLab). This laboratory would have a robot operated under telepresence from the space station or ground. Long duration experiments aboard RoboLab could be performed by astronauts or scientists using telepresence to operate equipment and perform experiments. Operating the lab by telepresence would eliminate the need for life support such as food, water and air. The robot would be capable of motion in three dimensions, have binocular vision TV cameras, and two arms with manipulators to simulate hands. The robot would move along a two-dimensional grid and have a rotating, telescoping periscope section for extension in the third dimension. The remote operator would wear a virtual reality type headset to allow the superposition of computer displays over the real-time video of the lab. The operators would wear exoskeleton type arms to facilitate the movement of objects and equipment operation. The combination of video displays, motion, and the exoskeleton arms would provide a high degree of telepresence, especially for novice users such as scientists doing short-term experiments. The RoboLab could be resupplied and samples removed on other space shuttle flights. A self-contained RoboLab module would be designed to fit within the cargo bay of the space shuttle. Different modules could be designed for specific applications, i.e., crystal-growing, medicine, life sciences, chemistry, etc. This paper describes a RoboLab simulation using virtual reality (VR). VR provides an ideal simulation of telepresence before the actual robot and laboratory modules are constructed. The easy simulation of different telepresence designs will produce a highly optimum design before construction rather than the more expensive and time consuming hardware changes afterwards.

Virtual Labs and Virtual Worlds

NASA Astrophysics Data System (ADS)

Boehler, Ted

2006-12-01

Virtual Labs and Virtual Worlds Coastline Community College has under development several virtual lab simulations and activities that range from biology, to language labs, to virtual discussion environments. Imagine a virtual world that students enter online, by logging onto their computer from home or anywhere they have web access. Upon entering this world they select a personalized identity represented by a digitized character (avatar) that can freely move about, interact with the environment, and communicate with other characters. In these virtual worlds, buildings, gathering places, conference rooms, labs, science rooms, and a variety of other “real world” elements are evident. When characters move about and encounter other people (players) they may freely communicate. They can examine things, manipulate objects, read signs, watch video clips, hear sounds, and jump to other locations. Goals of critical thinking, social interaction, peer collaboration, group support, and enhanced learning can be achieved in surprising new ways with this innovative approach to peer-to-peer communication in a virtual discussion world. In this presentation, short demos will be given of several online learning environments including a virtual biology lab, a marine science module, a Spanish lab, and a virtual discussion world. Coastline College has been a leader in the development of distance learning and media-based education for nearly 30 years and currently offers courses through PDA, Internet, DVD, CD-ROM, TV, and Videoconferencing technologies. Its distance learning program serves over 20,000 students every year. sponsor Jerry Meisner

Measurement of the beam asymmetry Σ and the target asymmetry T in the photoproduction of ω mesons off the proton using CLAS at Jefferson Laboratory

DOE PAGES

Roy, P.; Akbar, Z.; Park, S.; ...

2018-05-04

Here, the photoproduction ofmore » $$\\omega$$ mesons off the proton has been studied in the reaction $$\\gamma p\\to p\\,\\omega$$ using the CEBAF Large Acceptance Spectrometer (CLAS) and the frozen-spin target (FROST) in Hall B at the Thomas Jefferson National Accelerator Facility. For the first time, the target asymmetry, $T$, has been measured in photoproduction from the decay $$\\omega\\to\\pi^+\\pi^-\\pi^0$$, using a transversely-polarized target with energies ranging from just above the reaction threshold up to 2.8 GeV. Significant non-zero values are observed for these asymmetries, reaching about 30-40% in the third-resonance region. New measurements for the photon-beam asymmetry, $$\\Sigma$$, are also presented, which agree well with previous CLAS results and extend the world database up to 2.1 GeV. These data and additional $$\\omega$$-photoproduction observables from CLAS were included in a partial-wave analysis within the Bonn-Gatchina framework. Significant contributions from $s$-channel resonance production were found in addition to $t$-channel exchange processes.« less

Measurement of the beam asymmetry Σ and the target asymmetry T in the photoproduction of ω mesons off the proton using CLAS at Jefferson Laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roy, P.; Akbar, Z.; Park, S.

Here, the photoproduction ofmore » $$\\omega$$ mesons off the proton has been studied in the reaction $$\\gamma p\\to p\\,\\omega$$ using the CEBAF Large Acceptance Spectrometer (CLAS) and the frozen-spin target (FROST) in Hall B at the Thomas Jefferson National Accelerator Facility. For the first time, the target asymmetry, $T$, has been measured in photoproduction from the decay $$\\omega\\to\\pi^+\\pi^-\\pi^0$$, using a transversely-polarized target with energies ranging from just above the reaction threshold up to 2.8 GeV. Significant non-zero values are observed for these asymmetries, reaching about 30-40% in the third-resonance region. New measurements for the photon-beam asymmetry, $$\\Sigma$$, are also presented, which agree well with previous CLAS results and extend the world database up to 2.1 GeV. These data and additional $$\\omega$$-photoproduction observables from CLAS were included in a partial-wave analysis within the Bonn-Gatchina framework. Significant contributions from $s$-channel resonance production were found in addition to $t$-channel exchange processes.« less

Theoretical and Experimental Studies in Accelerator Physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rosenzweig, James

This report describes research supported by the US Dept. of Energy Office of High Energy Physics (OHEP), performed by the UCLA Particle Beam Physics Laboratory (PBPL). The UCLA PBPL has, over the last two decades-plus, played a critical role in the development of advanced accelerators, fundamental beam physics, and new applications enabled by these thrusts, such as new types of accelerator-based light sources. As the PBPL mission is broad it is natural that it has been grown within the context of the accelerator science and technology stewardship of the OHEP. Indeed, steady OHEP support for the program has always beenmore » central to the success of the PBPL; it has provided stability, and above all has set the over-arching themes for our research directions, which have producing over 500 publications (>120 in high level journals). While other agency support has grown notably in recent years, permitting more vigorous pursuit of the program, it is transient by comparison. Beyond permitting program growth in a time of flat OHEP budgets, the influence of other agency missions is found in push to adapt advanced accelerator methods to applications, in light of the success the field has had in proof-of-principle experiments supported first by the DoE OHEP. This three-pronged PBPL program — advanced accelerators, fundamental beam physics and technology, and revolutionary applications — has produced a generation of students that have had a profound affect on the US accelerator physics community. PBPL graduates, numbering 28 in total, form a significant population group in the accelerator community, playing key roles as university faculty, scientific leaders in national labs (two have been named Panofsky Fellows at SLAC), and vigorous proponents of industrial application of accelerators. Indeed, the development of advanced RF, optical and magnet technology at the PBPL has led directly to the spin-off company, RadiaBeam Technologies, now a leading industrial

Cultural resource applications for a GIS: Stone conservation at Jefferson and Lincoln Memorials

USGS Publications Warehouse

Joly, Kyle; Donald, Tony; Comer, Douglas

1998-01-01

Geographical information systems are rapidly becoming essential tools for land management. They provide a way to link landscape features to the wide variety of information that managers must consider when formulating plans for a site, designing site improvement and restoration projects, determining maintenance projects and protocols, and even interpreting the site. At the same time, they can be valuable research tools.Standing structures offer a different sort of geography, even though a humanly contrived one. Therefore, the capability of a geographical information system (GIS) to link geographical units to the information pertinent to the site and resource management can be employed in the management of standing structures. This was the idea that inspired the use of a GIS software, ArcView, to link computer aided design CAD) drawings of the Jefferson and Lincoln Memorials with inventories of the stones in the memorials. Both the CAD drawings and the inventory were in existence; what remained to be done was to modify the CAD files and place the inventory in an appropriately designed computerized database, and then to link the two in a GIS project. This work was carried out at the NPS Denver Service Center, Resource Planning Group, Applied Archaeology Center (DSC-RPG-AAC), in Silver Spring, Maryland, with the assistance of US/ICOMOS summer interns Katja Marasovic (Croatia) and Rastislav Gromnica (Slovakia), under the supervision of AAC office manager Douglas Comer. Project guidance was provided by Tony Donald, the Denver Service Center (DSC) project architect for the restoration of the Jefferson and Lincoln Memorials, and GIS consultation services by Kyle Joly.

GeneLab

NASA Technical Reports Server (NTRS)

Berrios, Daniel C.; Thompson, Terri G.

2015-01-01

NASA GeneLab is expected to capture and distribute omics data and experimental and process conditions most relevant to research community in their statistical and theoretical analysis of NASAs omics data.

Design and Implementation of the CEBAF Element Database

DOE Office of Scientific and Technical Information (OSTI.GOV)

Theodore Larrieu, Christopher Slominski, Michele Joyce

2011-10-01

With inauguration of the CEBAF Element Database (CED) in Fall 2010, Jefferson Lab computer scientists have taken a first step toward the eventual goal of a model-driven accelerator. Once fully populated, the database will be the primary repository of information used for everything from generating lattice decks to booting front-end computers to building controls screens. A particular requirement influencing the CED design is that it must provide consistent access to not only present, but also future, and eventually past, configurations of the CEBAF accelerator. To accomplish this, an introspective database schema was designed that allows new elements, element types, andmore » element properties to be defined on-the-fly without changing table structure. When used in conjunction with the Oracle Workspace Manager, it allows users to seamlessly query data from any time in the database history with the exact same tools as they use for querying the present configuration. Users can also check-out workspaces and use them as staging areas for upcoming machine configurations. All Access to the CED is through a well-documented API that is translated automatically from original C++ into native libraries for script languages such as perl, php, and TCL making access to the CED easy and ubiquitous. Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.« less

Awakening interest in the natural sciences - BASF's Kids' Labs.

PubMed

Lang, Cinthia

2012-01-01

At BASF's Ludwigshafen headquarters, kids and young adults in grades 1-13 can learn about chemistry in the Kids' Labs. Different programs exist for different levels of knowledge. In the two 'Hands-on Lab H(2)O & Co.' Kids' Labs, students from grades 1-6 explore the secrets of chemistry. BASF Kids' Labs have now been set up in over 30 countries. In Switzerland alone, almost 2,000 students have taken part in the 'Water Loves Chemistry' Kids' Lab since it was started in 2011. In Alsace, 600 students have participated to date. In the Teens' Lab 'Xplore Middle School', middle school students explore five different programs with the themes 'substance labyrinth', 'nutrition', 'coffee, caffeine & co.', 'cosmetics' and 'energy'. Biotechnological methods are the focus of the Teens' Lab 'Xplore Biotech' for students taking basic and advanced biology courses. In the 'Xplore High School' Teens' Lab, chemistry teachers present their own experimental lab instruction for students in basic and advanced chemistry courses. The Virtual Lab has been expanding the offerings of the BASF Kids' Labs since 2011. The online lab was developed by the company for the International Year Of Chemistry and gives kids and young adults the opportunity to do interactive experiments outside of the lab.

Instrument Design Optimization With Computational Methods

NASA Astrophysics Data System (ADS)

Moore, Michael H.

Using Finite Element Analysis to approximate the solution of differential equations, two different instruments in experimental Hall C at the Thomas Jefferson National Accelerator Facility are analyzed. The time dependence of density fluctuations from the liquid hydrogen (LH2) target used in the Qweak experiment (2011-2012) are studied with Computational Fluid Dynamics (CFD) and the simulation results compared to data from the experiment. The 2.5 kW liquid hydrogen target was the highest power LH2 target in the world and the first to be designed with CFD at Jefferson Lab. The first complete magnetic field simulation of the Super High Momentum Spectrometer (SHMS) is presented with a focus on primary electron beam deflection downstream of the target. The SHMS consists of a superconducting horizontal bending magnet (HB) and three superconducting quadrupole magnets. The HB allows particles scattered at an angle of 5.5° to the beam line to be steered into the quadrupole magnets which make up the optics of the spectrometer. Without mitigation, remnant fields from the SHMS may steer the unscattered beam outside of the acceptable envelope on the beam dump and limit beam operations at small scattering angles. A solution is proposed using optimal placement of a minimal amount of shielding iron around the beam line.

Hadronization Studies via π 0 Electroproduction off D, C, Fe, and Pb

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mineeva, Taisiya

2013-12-01

Propagation of partons and formation of hadrons is a topic of interest to multiple communities. New data available from Drell-Yan measurements at FermiLab, heavy ion collisions in RHIC and LHC, SIDIS measurements from HERMES at DESY and Jefferson Lab, all bring different types of information on short distance processes. DIS data obtained in the well understood nuclear medium provide direct information on hadron formation, essential to lay the groundwork for testing theoretical tools. A series of semi-inclusive DIS measurements were performed on D, C, Fe, Pb nuclei. The data were collected during the EG2 run period using the CLAS at Jefferson Lab. A double-target system consisting of liquid deuterium and one of the solid targets was exposed to a 5.014 GeV electron beam. The goal of the experiment is to extract hadronic multiplicity ratios (Rmore » $$h\\atop{A}$$) off nuclei of varying size. These are believed to have sensitivity to the parton fragmentation as well as in-medium hadronization.« less

Petrographic and geochemical investigation of magma chamber processes beneath small Quaternary volcanic centers between Mt. Jefferson and Mt. Hood volcanoes, Cascade Range Volcanic Arc

NASA Astrophysics Data System (ADS)

Cunningham, E.; Cribb, J. W.

2017-12-01

The northern Oregon Cascade Range has been dominated by andesite to rhyodacite lavas at both Mt. Jefferson (Conrey, 1991) and at Mt. Hood (Cribb and Barton, 1996) during the Quaternary period. Eruptive sequences at both Mt. Hood and Mt. Jefferson have been attributed to open-system mama mixing (Kent et al., 2010) (Ferrell et al., 2015), and the narrow range of lavas erupted at both centers has been derived from repeated cycles of magma mixing-fractionation (Cribb and Barton, 1996). This research examines major and trace element geochemistry as well as the petrographic characteristics of Clear Lake Butte (CLB), Pinhead Butte (PB), and Olallie Butte (OB), all of which are located between Mt. Hood and Mt. Jefferson, and have ben active in the Quaternary period. The research investigates whether the same type of open-system magma mixing known to have occurred at Mt. Hood and Mt. Jefferson has also occurred at CLB, PB, or OB, or whether those systems were closed to mixing and dominated by fractional crystallization. One of the main goals of this project is to highlight the similarities and differences exhibited by neighboring magmatic systems of similar age, but different scale. Disequilibrium textures observed in thin sections from CLB, OB, and PB suggest open-system magma mixing is likely occurring beneath all three buttes. This petrographic evidence includes plagioclase and pyroxene zoning, embayed margins, sieving, and reaction rims. Major element oxide trends at all three buttes are consistent with fractional crystallization, but show narrow concentrations and non-overlapping compositions between PB, CLB, and OB. All three buttes are characterized by narrow ranges of incompatible and compatible trace element concentrations. CLB, PB, and OB all exhibit LREE enrichment and lack significant HFSE depletions, with PB exhibiting greatest enrichment in REE.

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

PubMed

Hu, Yong; Yuan, Zhen-Shan; Kepler, Christopher K; Dong, Wei-Xin; Sun, Xiao-Yang; Zhang, Jiao

2017-01-01

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. 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. 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. 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.

Curricular Adaptations in Introductory Physics Labs

NASA Astrophysics Data System (ADS)

Dreyfus, Benjamin W.; Ewell, Mary; Moore, Kimberly

2017-01-01

When curricular materials are disseminated to new sites, there can be a tension between fidelity to the original intent of the developers and adaptation to local needs. In this case study we look at a lab activity that was initially developed for an introductory physics for the life sciences (IPLS) course at the University of Maryland, then implemented at George Mason University with significant adaptations. The goals of the two implementations were overlapping, but also differed in ways that are reflected in the two versions of the lab. We compare student lab report data from the two sites to examine the impacts of the adaptation on how students engaged with the lab.

Lab architecture

NASA Astrophysics Data System (ADS)

Crease, Robert P.

2008-04-01

There are few more dramatic illustrations of the vicissitudes of laboratory architecturethan the contrast between Building 20 at the Massachusetts Institute of Technology (MIT) and its replacement, the Ray and Maria Stata Center. Building 20 was built hurriedly in 1943 as temporary housing for MIT's famous Rad Lab, the site of wartime radar research, and it remained a productive laboratory space for over half a century. A decade ago it was demolished to make way for the Stata Center, an architecturally striking building designed by Frank Gehry to house MIT's computer science and artificial intelligence labs (above). But in 2004 - just two years after the Stata Center officially opened - the building was criticized for being unsuitable for research and became the subject of still ongoing lawsuits alleging design and construction failures.

Micro-Bubble Experiments at the Van de Graaff Accelerator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Z. J.; Wardle, Kent E.; Quigley, K. J.

In order to test and verify the experimental designs at the linear accelerator (LINAC), several micro-scale bubble ("micro-bubble") experiments were conducted with the 3-MeV Van de Graaff (VDG) electron accelerator. The experimental setups included a square quartz tube, sodium bisulfate solution with different concentrations, cooling coils, gas chromatography (GC) system, raster magnets, and two high-resolution cameras that were controlled by a LabVIEW program. Different beam currents were applied in the VDG irradiation. Bubble generation (radiolysis), thermal expansion, thermal convection, and radiation damage were observed in the experiments. Photographs, videos, and gas formation (O 2 + H 2) data were collected.more » The micro-bubble experiments at VDG indicate that the design of the full-scale bubble experiments at the LINAC is reasonable.« less

Final analysis of proton form factor ratio data at Q 2 = 4.0, 4.8, and 5.6 GeV 2

DOE PAGES

Puckett, A. J. R.; Brash, E. J.; Gayou, O.; ...

2012-04-11

Recently published measurements of the proton electromagnetic form factor ratio R = μ p G E p/G M p at momentum transfers Q 2 up to 8.5 GeV 2 in Jefferson Lab Hall C deviate from the linear trend of previous measurements in Jefferson Lab Hall A, favoring a slower rate of decrease of R with Q 2. While statistically compatible in the region of overlap with Hall A, the Hall C data hint at a systematic difference between the two experiments. This possibility was investigated in a reanalysis of the Hall A data. We find that the original analysismore » underestimated the background in the selection of elastic events. The application of an additional cut to further suppress the background increases the results for R, improving the consistency between Halls A and C.« less

Generalized Nanosatellite Avionics Testbed Lab

NASA Technical Reports Server (NTRS)

Frost, Chad R.; Sorgenfrei, Matthew C.; Nehrenz, Matt

2015-01-01

The Generalized Nanosatellite Avionics Testbed (G-NAT) lab at NASA Ames Research Center provides a flexible, easily accessible platform for developing hardware and software for advanced small spacecraft. A collaboration between the Mission Design Division and the Intelligent Systems Division, the objective of the lab is to provide testing data and general test protocols for advanced sensors, actuators, and processors for CubeSat-class spacecraft. By developing test schemes for advanced components outside of the standard mission lifecycle, the lab is able to help reduce the risk carried by advanced nanosatellite or CubeSat missions. Such missions are often allocated very little time for testing, and too often the test facilities must be custom-built for the needs of the mission at hand. The G-NAT lab helps to eliminate these problems by providing an existing suite of testbeds that combines easily accessible, commercial-offthe- shelf (COTS) processors with a collection of existing sensors and actuators.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

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, computedmore » tomography is useful to demonstrate an intact atlas ring.« less

Trails through time: A geologist's guide to Jefferson County open space parks

USGS Publications Warehouse

Reed, John C.

2014-01-01

Jefferson County Open Space Parks, as well as other nearby parks and National Forest lands, offer marvelousopportunities to explore the geologic story behind this singular landscape. At first the distribution of rocks of differentages and types seems almost random, but careful study of the rocks and landscape features reveals a captivatinggeologic story, a history that tells of the building of the foundations of the continent, the rise and destruction of longvanishedmountain ranges, the ebb and flow of ancient seas, and the constant shaping and reshaping of the landscape inresponse to the never-ending interplay between uplift and erosion. This historical account is constantly being improvedand expanded as new evidence accumulates and new interpretations evolve.

FRIB Cryogenic Distribution System and Status

NASA Astrophysics Data System (ADS)

Ganni, V.; Dixon, K.; Laverdure, N.; Yang, S.; Nellis, T.; Jones, S.; Casagrande, F.

2015-12-01

The MSU-FRIB cryogenic distribution system supports the 2 K primary, 4 K primary, and 35 - 55 K shield operation of more than 70 loads in the accelerator and the experimental areas. It is based on JLab and SNS experience with bayonet-type disconnects between the loads and the distribution system for phased commissioning and maintenance. The linac transfer line, which features three separate transfer line segments for additional independence during phased commissioning at 4 K and 2 K, connects the folded arrangement of 49 cryomodules and 4 superconducting dipole magnets and a fourth transfer line supports the separator area cryo loads. The pressure reliefs for the transfer line process lines, located in the refrigeration room outside the tunnel/accelerator area, are piped to be vented outdoors. The transfer line designs integrate supply and return flow paths into a combined vacuum space. The main linac distribution segments are produced in a small number of standard configurations; a prototype of one such configuration has been fabricated at Jefferson Lab and has been installed at MSU to support testing of a prototype FRIB cryomodule.

High current polarized electron source

NASA Astrophysics Data System (ADS)

Suleiman, R.; Adderley, P.; Grames, J.; Hansknecht, J.; Poelker, M.; Stutzman, M.

2018-05-01

Jefferson Lab operates two DC high voltage GaAs photoguns with compact inverted insulators. One photogun provides the polarized electron beam at the Continuous Electron Beam Accelerator Facility (CEBAF) up to 200 µA. The other gun is used for high average current photocathode lifetime studies at a dedicated test facility up to 4 mA of polarized beam and 10 mA of un-polarized beam. GaAs-based photoguns used at accelerators with extensive user programs must exhibit long photocathode operating lifetime. Achieving this goal represents a significant challenge for proposed facilities that must operate in excess of tens of mA of polarized average current. This contribution describes techniques to maintain good vacuum while delivering high beam currents, and techniques that minimize damage due to ion bombardment, the dominant mechanism that reduces photocathode yield. Advantages of higher DC voltage include reduced space-charge emittance growth and the potential for better photocathode lifetime. Highlights of R&D to improve the performance of polarized electron sources and prolong the lifetime of strained-superlattice GaAs are presented.

Planning a Computer Lab: Considerations To Ensure Success.

ERIC Educational Resources Information Center

IALL Journal of Language Learning Technologies, 1994

1994-01-01

Presents points to consider when organizing a computer laboratory. These include the lab's overall objectives and how best to meet them; what type of students will use the lab; where the lab will be located; and what software and hardware can best meet the lab's overall objectives, population, and location requirements. Other factors include time,…

TQM in a Computer Lab.

ERIC Educational Resources Information Center

Swanson, Dewey A.; Phillips, Julie A.

At the Purdue University School of Technology (PST) at Columbus, Indiana, the Total Quality Management (TQM) philosophy was used in the computer laboratories to better meet student needs. A customer satisfaction survey was conducted to gather data on lab facilities, lab assistants, and hardware/software; other sections of the survey included…

Berkeley Lab - Materials Sciences Division

Science.gov Websites

Synthesis Condensed Matter and Materials Physics Scattering and Instrumentation Science Centers Center for Berkeley Lab Berkeley Lab A-Z Index Phone Book Jobs Search DOE Search MSD Go MSD - Materials Sciences Division About Organization Contact Research Core Programs Materials Discovery, Design and

The eye disease of Jefferson Davis (1808-1889).

PubMed

Hertle, Richard W; Spellman, Robert

2007-01-01

The only Confederate president, Jefferson Davis, led a long and eventful life. He was a Mississippi planter, a husband, a father, West Point graduate, war hero, congressman, senator, secretary of war, and finally President of the Confederate States of America. In many ways he was a study of contrast with his northern counterpart Abraham Lincoln. Davis was personally courageous and a rich, educated, southern aristocrat who did not deeply understand the political process or have the refined personal skills necessary to work well with others. Prior to his Presidency he served with distinction in two wars, but as a result of his confederate activity and pro-slavery philosophy he is one of the least discussed famous Americans. Davis's health was a constant problem and he suffered an almost fatal attack of 'malaria' in 1836. In the winter of 1857-1858, he again was seriously ill and by the end of February 1858, a chronic, relapsing, ocular inflammatory condition began. Using historical evidence from multiple sources, this paper will propose a diagnosis of the Confederate President's ocular condition and consider how this could have influenced his military and political decisions.

The eye disease of Jefferson Davis (1808-1889).

PubMed

Hertle, Richard W; Spellman, Robert

2006-01-01

The only Confederate president, Jefferson Davis, led a long and eventful life. He was a Mississippi planter, a husband, a father, West Point graduate, war hero, congressman, senator, secretary of war, and finally President of the Confederate States of America. In many ways he was a study of contrast with his northern counterpart, Abraham Lincoln. Davis was personally courageous and a rich, educated, southern aristocrat who did not deeply understand the political process or have the refined personal skills necessary to work well with others. Prior to his Presidency he served with distinction in two wars, but as a result of his confederate activity and pro-slavery philosophy he is one of the least discussed famous Americans. Davis's health was a constant problem and he suffered an almost fatal attack of "malaria" in 1836. In the winter of 1857-1858 he again was seriously ill and by the end of February 1858 a chronic, relapsing, ocular inflammatory condition began. Using historical evidence from multiple sources, this paper will propose a diagnosis of the Confederate President's ocular condition and consider how this could have influenced his military and political decisions.

Future{at}Labs.Prosperity Game{trademark}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beck, D.F.; Boyack, K.W.; Berman, M.

Prosperity Games{trademark} are an outgrowth and adaptation of move/countermove and seminar War Games, Prosperity Games{trademark} are simulations that explore complex issues in a variety of areas including economics, politics, sociology, environment, education, and research. These issues can be examined from a variety of perspectives ranging from global, macroeconomic and geopolitical viewpoint down to the details of customer/supplier/market interactions specific industries. All Prosperity Games{trademark} are unique in that both the game format and the player contributions vary from game to game. This report documents the Future{at}Labs.Prosperity Game{trademark} conducted under the sponsorship of the Industry Advisory Boards of the national labs, themore » national labs, Lockheed Martin Corporation, and the University of California. Players were drawn from all stakeholders involved including government, industry, labs, and academia. The primary objectives of this game were to: (1) explore ways to optimize the role of the multidisciplinary labs in serving national missions and needs; (2) explore ways to increase collaboration and partnerships among government, laboratories, universities, and industry; and (3) create a network of partnership champions to promote findings and policy options. The deliberations and recommendations of these players provided valuable insights as to the views of this diverse group of decision makers concerning the future of the labs.« less

Design of inquiry-oriented science labs: impacts on students' attitudes

NASA Astrophysics Data System (ADS)

Baseya, J. M.; Francis, C. D.

2011-11-01

Background: Changes in lab style can lead to differences in learning. Two inquiry-oriented lab styles are guided inquiry (GI) and problem-based (PB). Students' attitudes towards lab are important to consider when choosing between GI and PB styles during curriculum design. Purpose: We examined the degree to which lab experiences are explained by a GI or a PB lab style vs. students' attitudes towards specific aspects of the experience, reflected by perceived excitement (exc), difficulty (dif), time efficiency (eff) and association between lab and lecture material (help). Sample: Approximately 1000 students attending first-semester, college biology lab for science majors at the University of Colorado at Boulder, USA, participated in the study. Design and method: In 2007, two labs were run as GI and one as PB. Formats were switched in 2008. Attitudes were assessed with a post-semester survey. Results: Only the four attitude variables (not lab style) had a strong relationship with overall lab rating which was most strongly related to exc, followed by dif and help/eff. Dif and eff had the greatest influence on attitudes for or against GI vs. PB labs, and help and exc had little influence on a GI vs. a PB lab. Also, when dif was low, students' attitudes were not significantly different between PB and GI labs, but when dif was high, students' significantly rated GI labs higher than PB labs. Conclusions: Students' attitudes towards lab are more dependent on specific aspects of the experience than on lab style. Changes in GI vs. PB lab styles primarily influence dif and eff rather than exc and help. Dif may be an important factor to consider when implementing a lab in the PB vs. the GI format. It might be good to go with a GI when dif is high and a PB when dif is low.

Science Lab: A Peer Approach.

ERIC Educational Resources Information Center

Ronca, Courtney C.

The two goals of this program were to increase the number of classroom teachers using the lab and to increase the amount of time that the science lab was used. The solution strategy chosen was a combination of peer tutoring, orientation presentations, small group discovery experiments and activities, and individual science experiment stations. The…

Studies of GPDs at Jefferson Lab: results and future experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Biselli, Angela

Here, 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), eN → e'N'γ, is one of the simplest processes that can be described in terms of GPDs. The amplitudes of DVCS and Bethe-Heitler, process where a photon is emitted by the incident or scattered electron, can be accessed via cross section measurements or exploiting their interference which give rise to spin asymmetries. Spin asymmetries, cross sections and cross-section differences can be connected to different combinations of the four leading order GPDs (H, E,more » $$\\tilde{H} $$, $$\\tilde{E} $$) for the two quark flavors depending on the observable and the type of target.« less

Studies of GPDs at Jefferson Lab: results and future experiments

DOE PAGES

Biselli, Angela

2018-01-05

Here, 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), eN → e'N'γ, is one of the simplest processes that can be described in terms of GPDs. The amplitudes of DVCS and Bethe-Heitler, process where a photon is emitted by the incident or scattered electron, can be accessed via cross section measurements or exploiting their interference which give rise to spin asymmetries. Spin asymmetries, cross sections and cross-section differences can be connected to different combinations of the four leading order GPDs (H, E,more » $$\\tilde{H} $$, $$\\tilde{E} $$) for the two quark flavors depending on the observable and the type of target.« less

Recent Results of TMD Measurements from Jefferson Lab Hall A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Xiaodong

2013-10-01

This slide-show presents results on transverse momentum distributions. The presentation covers: target single-spin asymmetry (SSA) (in parity conserving interactions); • Results of JLab Hall A polarized {sup 3}He target TMD measurement; • Semi-­inclusive deep-inelastic scattering channels (E06-010); • Target single-spin asymmetry A{sub UT}, Collins and Sivers SSA on neutron; • Double-spin asymmetry A{sub LT}, extract TMD g{sub 1T} on neutron; • Inclusive channels SSA (E06-010, E05-015, E07-013) • Target SSA: inclusive {sup 3}He(e,e’) quasi-elastic scattering; • Target SSA: inclusive {sup 3}He(e,e’) deep inelastic-elastic scattering; • New SIDIS experiments planned in Hall-A for JLab-12 GeV.

Colour stability of temporary restorations with different thicknesses submitted to artificial accelerated aging.

PubMed

Silame, F D J; Tonani, R; Alandia-Roman, C C; Chinelatti, M; Panzeri, H; Pires-de-Souza, F C P

2013-12-01

This study evaluated the colour stability of temporary prosthetic restorations with different thicknesses submitted to artificial accelerated aging. The occlusal surfaces of 40 molars were grinded to obtain flat enamel surfaces. Twenty acrylic resin specimens [Polymethyl methacrylate (Duralay) and Bis-methyl acrylate (Luxatemp)] were made with two different thicknesses, 0.5 mm and 1.0 mm. Temporary restorations were fixed on enamel and CIE L*a*b* colour parameters of each specimen were assessed before and after artificial accelerated aging. All groups showed colour alterations above the clinically acceptable limit. Luxatemp showed the lowest colour alteration regardless its thickness and Duralay showed the greatest alteration with 0.5 mm.

Report of Block Field Experience at Jefferson County Department of Health Bureau of Nutrition, Birmingham, Alabama.

DTIC Science & Technology

1985-01-01

Despite the recent economic growth of Jefferson County, poverty * still abounds. In 1980, 12% of the families lived below the poverty level and some...residents with the charge for services being based on a sliding fee scale. Those at or below 150% of poverty level are charged only a minimum fee. F...be at risk? 1. Poor dietary calcium intake - average intake for American women is less than 500 grams per day. 2. Smoking - nicotine hurries the

The large-area hybrid-optics RICH detector for the CLAS12 spectrometer

DOE PAGES

Mirazita, M.; Angelini, G.; Balossino, I.; ...

2017-01-16

A large area ring-imaging Cherenkov detector has been designed to provide clean hadron identification capability in the momentum range from 3 GeV/c to 8 GeV/c for the CLAS12 experiments at the upgraded 12 GeV continuous electron beam accelerator facility of Jefferson Lab to study the 3D nucleon structure in the yet poorly explored valence region by deep-inelastic scattering, and to perform precision measurements in hadronization and hadron spectroscopy. The adopted solution foresees a novel hybrid optics design based on an aerogel radiator, composite mirrors and densely packed and highly segmented photon detectors. Cherenkov light will either be imaged directly (forwardmore » tracks) or after two mirror reflections (large angle tracks). Finally, the preliminary results of individual detector component tests and of the prototype performance at test-beams are reported here.« less

LANGUAGE LABS--AN UPDATED REPORT.

ERIC Educational Resources Information Center

1963

REPORTS FROM SEVERAL SCHOOL DISTRICTS ON THE USE OF AND PLANNING OF LANGUAGE LABORATORIES ARE PRESENTED. LABORATORIES SHOULD BE ARRANGED FOR FLEXIBLE USE. THE AVERAGE HIGH SCHOOL STUDENT CAN USE A LAB PROFITABLY FOR 20 TO 25 MINUTES. THERE ARE THREE DIFFERENT TYPES OF LANGUAGE LABORATORIES THAT ARE DESCRIBED. THE SATELLITE LAB IS DIVIDED BY A…

Academic Pipeline and Futures Lab

DTIC Science & Technology

2016-02-01

AFRL-RY-WP-TR-2015-0186 ACADEMIC PIPELINE AND FUTURES LAB Brian D. Rigling Wright State University FEBRUARY 2016...DD-MM-YY) 2. REPORT TYPE 3. DATES COVERED (From - To) February 2016 Final 12 June 2009 – 30 September 2015 4. TITLE AND SUBTITLE ACADEMIC ...6 3 WSU ACADEMIC PIPELINE AND LAYERED SENSING FUTURES LAB (prepared by K

Berkeley Lab - Materials Sciences Division

Science.gov Websites

Synthesis Condensed Matter and Materials Physics Scattering and Instrumentation Science Centers Center for materials and phenomena at multiple time and length scales. Through our core programs and research centers Berkeley Lab Berkeley Lab A-Z Index Phone Book Jobs Search DOE Search MSD Go MSD - Materials

National Dam Safety Program. Cedar Hill Lake Number 2 and Number 3 Dams (MO 30005) and (MO 31020), Mississippi - Kaskaskia - St. Louis Basin, Jefferson County, Missouri. Phase I Inspection Report.

DTIC Science & Technology

1979-01-01

ST. LOUIS I3ASIN ’ADA l1047 82 -3 CEDAR HILL LAKE NO. 2 AND NO. 5 DAMS 5JEFFERSON COUNTY, MISSOURI SMO 30005 AND MO 31020% SPHASE I INSPECTION REPORT...and Number 3 17. DISTRIBUTION STATEMENT (of the abstraect Un ((NO 30005 and MO 31020),, Mississippi - Kaskaskia - St. Louis i ,-_Basin, Jefferson County...results of field inspection and evaluation of Cedar Hill No. 2 and No. 3 Dams (Mo. 30005 and 31020). It was prepared under the National Program of

Towards a Manifesto for Living Lab Co-creation

NASA Astrophysics Data System (ADS)

Følstad, Asbjørn; Brandtzæg, Petter Bae; Gulliksen, Jan; Börjeson, Mikael; Näkki, Pirjo

There is a growing interest in Living Labs for innovation and development in the field of information and communication technology. In particular there seem to be a tendency that current Living Labs aim to involve users for co-creative purposes. However, the current literature on Living Lab co-creation is severely limited. Therefore an Interact workshop is arranged as a first step towards a manifesto for Living Lab co-creation.

Study of generalized parton distributions and deeply virtual compton scattering on the nucleon with the CLAS and CLAS12 detectors at the Jefferson Laboratory

NASA Astrophysics Data System (ADS)

Guegan, Baptiste

The Generalized Parton Distributions (GPDs) provide a new description of the nucleon structure in terms of its elementary constituents, the quarks and the gluons. The GPDs give access to a unified picture of the nucleon, correlating the information obtained from the measurements of the Form Factors and the Parton Distribution Functions. They describe the correlation between the transverse position and the longitudinal momentum fraction of the partons in the nucleon. Deeply Virtual Compton Scattering (DVCS), the electroproduction of a real photon on a single quark of the nucleon eN → eN'gamma , is the most straightforward exclusive process allowing access to the GPDs. The DVCS process interferes with the Bethe-Heitler (BH) process, in which the real photon is emitted by either the incoming or the scattered electron instead of the nucleon. A dedicated experiment to study DVCS with the CLAS detector of Jefferson Lab has been carried out using a 5.883 GeV polarized electron beam and an unpolarized hydrogen target, allowing to collect DVCS events in the widest kinematic range ever explored in the valence region : 1 < Q2 < 4.6 GeV2, 0.1 < xB < 0.58, 0.09 < -t < 3 GeV2. We will present preliminary results on the extraction of the unpolarized and the difference of polarized DVCS cross sections. We will show a preliminary extraction of the GPDs using the latest fitting code procedure on our data, and a preliminary interpretation of the results.

15. VIEW OF LABORATORY EQUIPMENT IN THE BUILDING 771 ANALYTICAL ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

15. VIEW OF LABORATORY EQUIPMENT IN THE BUILDING 771 ANALYTICAL LABORATORY. THE LAB ANALYZED SAMPLES FOR PLUTONIUM, AMERICIUM, URANIUM, NEPTUNIUM, AND OTHER RADIOACTIVE ISOTOPES. (9/25/62) - Rocky Flats Plant, Plutonium Recovery & Fabrication Facility, North-central section of plant, Golden, Jefferson County, CO

Berkeley Lab 2nd Grader Outreach

ScienceCinema

Scoggins, Jackie; Louie, Virginia

2017-12-11

The Berkeley Lab IT Department sponsored a community outreach program aimed at teaching young children about computers and networks. Second graders from LeConte Elementary School joined Lab IT Staff for a day of in-depth exercises and fun.

Labs: 1987.

ERIC Educational Resources Information Center

Igelsrud, Don, Ed.

1988-01-01

This article presents a variety of topics discussed in this column and at a biology teachers' workshop concerning the quality and value of lab techniques used for teaching high school biology. Topics included are Drosophila salivary glands, sea urchins, innovations, dyes and networking. (CW)

Berkeley Lab - Materials Sciences Division

Science.gov Websites

-486-6999 Urgent Radiation Protection Group Assistance Non-Life Threatening Event 24/7 Lab Phone: x7277 : 911 (no extentions required now) Non-Emergency Reporting (Fire and Police) Non-Life Threatening Event Spill Non-Life Threatening Event 24/7 Lab Phone: x6999 Cell Phone: 510-486-6999 Off Site Locations: 510

Report from the banding lab

USGS Publications Warehouse

Tautin, J.

1995-01-01

Mr. Tautin reported on the seemingly everchanging structure of biological science units within the Interior Department. Current Congressional proposals would either change the name of the Bird Banding Lab's parent agency or make it part of the Geological Survey. The current Congress has not looked favorably on science budgets within the Interior Department, and the Banding Lab's budget is being squeezed ever tighter.

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

PubMed

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.

JLab Measurements of the He 3 Form Factors at Large Momentum Transfers

DOE PAGES

Camsonne, A.; Katramatou, A. T.; Olson, M.; ...

2017-10-19

The charge and magnetic form factors, F C and F M, respectively, of 3He are extracted in the kinematic range 25 fm –2 ≤ Q 2 ≤ 61 fm –2 from elastic electron scattering by detecting 3He recoil nuclei and scattered electrons in coincidence with the two High Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The measurements find evidence for the existence of a second diffraction minimum for the magnetic form factor at Q 2 = 49.3 fm –2 and for the charge form factor at Q 2 = 62.0 fm –2. Both minima are predicted tomore » exist in the Q 2 range accessible by this Jefferson Lab experiment. Here, the data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the three-body nuclear problem.« less

JLab Measurements of the He 3 Form Factors at Large Momentum Transfers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Camsonne, A.; Katramatou, A. T.; Olson, M.

The charge and magnetic form factors, F C and F M, respectively, of 3He are extracted in the kinematic range 25 fm –2 ≤ Q 2 ≤ 61 fm –2 from elastic electron scattering by detecting 3He recoil nuclei and scattered electrons in coincidence with the two High Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The measurements find evidence for the existence of a second diffraction minimum for the magnetic form factor at Q 2 = 49.3 fm –2 and for the charge form factor at Q 2 = 62.0 fm –2. Both minima are predicted tomore » exist in the Q 2 range accessible by this Jefferson Lab experiment. Here, the data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the three-body nuclear problem.« less

The design and implementation of a broadband digital low-level RF control system for the cyclotron accelerators at iThemba LABS

NASA Astrophysics Data System (ADS)

Duckitt, W. D.; Conradie, J. L.; van Niekerk, M. J.; Abraham, J. K.; Niesler, T. R.

2018-07-01

iThemba LABS has successfully designed a new broadband digital low-level RF control system for cyclotrons, that operates over the wide frequency range of 2-100 MHz and can achieve peak-peak amplitude and phase stabilities of 0.01% and 0.01°, respectively. The presented system performs direct digital synthesis (DDS) to directly convert the digital RF signals to analog RF and local-oscillator (LO) signals with 16-bit amplitude accuracy, programmable in steps of 1 μHz and 0.0001°. Down-conversion of the RF pick-up signals to an optimal intermediate frequency (IF) of 1 MHz and sampling of the IF channels by 16-bit, single sample-latency 10 MHz ADCs was implemented to allow digital high-speed low-latency in-phase/quadrature (I/Q) demodulation of the IF channels within the FPGA. This in turn allows efficient real-time digital closed-loop control of the amplitude and phase of the RF drive-signal to be achieved. The systems have been successfully integrated at iThemba LABS into the K = 8 and K = 10 injector cyclotrons (SPC1, and SPC2), the K = 200 separated sector cyclotron (SSC), the SSC flat-topping system, the pulse-selector system and the AX , J, and K-line RF bunchers. The systems have led to a substantial improvement in the beam quality of the SSC at iThemba LABS with a reduction in beam losses by more than 90%. The design, implementation and performance is discussed.

Computer-based Astronomy Labs for Non-science Majors

NASA Astrophysics Data System (ADS)

Smith, A. B. E.; Murray, S. D.; Ward, R. A.

1998-12-01

We describe and demonstrate two laboratory exercises, Kepler's Third Law and Stellar Structure, which are being developed for use in an astronomy laboratory class aimed at non-science majors. The labs run with Microsoft's Excel 98 (Macintosh) or Excel 97 (Windows). They can be run in a classroom setting or in an independent learning environment. The intent of the labs is twofold; first and foremost, students learn the subject matter through a series of informational frames. Next, students enhance their understanding by applying their knowledge in lab procedures, while also gaining familiarity with the use and power of a widely-used software package and scientific tool. No mathematical knowledge beyond basic algebra is required to complete the labs or to understand the computations in the spreadsheets, although the students are exposed to the concepts of numerical integration. The labs are contained in Excel workbook files. In the files are multiple spreadsheets, which contain either a frame with information on how to run the lab, material on the subject, or one or more procedures. Excel's VBA macro language is used to automate the labs. The macros are accessed through button interfaces positioned on the spreadsheets. This is done intentionally so that students can focus on learning the subject matter and the basic spreadsheet features without having to learn advanced Excel features all at once. Students open the file and progress through the informational frames to the procedures. After each procedure, student comments and data are automatically recorded in a preformatted Lab Report spreadsheet. Once all procedures have been completed, the student is prompted for a filename in which to save their Lab Report. The lab reports can then be printed or emailed to the instructor. The files will have full worksheet and workbook protection, and will have a "redo" feature at the end of the lab for students who want to repeat a procedure.

Evaluation of oral microbiology lab curriculum reform.

PubMed

Nie, Min; Gao, Zhen Y; Wu, Xin Y; Jiang, Chen X; Du, Jia H

2015-12-07

According to the updated concept of oral microbiology, the School of Stomatology, Wuhan University, has carried out oral microbiology teaching reforms during the last 5 years. There was no lab curriculum before 2009 except for a theory course of oral microbiology. The school has implemented an innovative curriculum with oral medicine characteristics to strengthen understanding of knowledge, cultivate students' scientific interest and develop their potential, to cultivate the comprehensive ability of students. This study was designed to evaluate the oral microbiology lab curriculum by analyzing student performance and perceptions regarding the curriculum from 2009 to 2013. The lab curriculum adopted modalities for cooperative learning. Students collected dental plaque from each other and isolated the cariogenic bacteria with selective medium plates. Then they purified the enrichment culture medium and identified the cariogenic strains by Gram stain and biochemical tests. Both quantitative and qualitative data for 5 years were analysed in this study. Part One of the current study assessed student performance in the lab from 2009 to 2013. Part Two used qualitative means to assess students' perceptions by an open questionnaire. The 271 study students' grades on oral microbiology improved during the lab curriculum: "A" grades rose from 60.5 to 81.2 %, and "C" grades fell from 28.4 to 6.3 %. All students considered the lab curriculum to be interesting and helpful. Quantitative and qualitative data converge to suggest that the lab curriculum has strengthened students' grasp of important microbiology-related theory, cultivated their scientific interest, and developed their potential and comprehensive abilities. Our student performance and perception data support the continued use of the innovative teaching system. As an extension and complement of the theory course, the oral microbiology lab curriculum appears to improve the quality of oral medicine education and help to

Measurements of neutron skin in calcium and lead

NASA Astrophysics Data System (ADS)

Michaels, Robert

2017-01-01

Measurement of the parity-violating electron scattering asymmetry from 208Pb has demonstrated a new opportunity at Jefferson Lab to measure the weak charge form factor and hence pin down the neutron radius in nuclei in a relatively clean and model-independent way. This is because the Z boson of the weak interaction couples primarily to neutrons. We will describe the PREX and CREX experiments on 208Pb and 48Ca respectively. PREX-I ran in 2010, and CREX and a second run of PREX are currently in preparation. These are both doubly-magic nuclei whose first excited state can be discriminated by the high resolution spectrometers at JLab. The heavier lead nucleus, with a neutron excess, provides an interpretation of the neutron skin thickness in terms of properties of bulk neutron matter. For the lighter 48Ca nucleus, which is also rich in neutrons, microscopic nuclear theory calculations are feasible and are sensitive to poorly constrained 3-neutron forces. The measuements are a fundamental test of nuclear structure with applications to heavy ion research and neutron stars. Jefferson Science Associates, LLC, which operates Jefferson Lab for the U.S. DOE under U.S. DOE contract DE-AC05-060R23177.

Innovation - A view from the Lab

USDA-ARS?s Scientific Manuscript database

The USDA Ag Lab in Peoria helps bridge the gap between agricultural producers and commercial manufacturers. In 2015, the Ag Lab, officially known as the Agricultural Research Service (ARS) National Center for Agricultural Utilization Research (NCAUR), is celebrating 75 years of research in Peoria. T...

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

NASA Astrophysics Data System (ADS)

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

LABS Foundational Technology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Olson, Jerry

2012-01-01

They are the inventors of our generation dedicated to exceptional science, advancing the technologies of tomorrow. CO-LABS honors the outstanding achievements of researchers and their impact on the world.

Acceptance Tests for AMS Radiocarbon Measurements at iThemba LABS, Gauteng, South Africa

NASA Astrophysics Data System (ADS)

Mbele, Vela L.; Mullins, Simon M.; Winkler, Stephan R.; Woodborne, Stephan

The accelerator mass spectrometer was commissioned recently at the iThemba LABS 6 MV tandem accelerator. Improvements in the vacuum system, requiring procurement of cryo-pumps and the reducing the tank pressure of the N2 + CO2 insulation gas mixture below the level used for IBA measurements, were necessary. This resulted in the reduction of the nitrogen background and improved the resolution of 14C from 14N background in the ionisation chamber. The nitrogen was leaking to the stripping canal because of inadequate sealing. The analysing magnet was scaled to detect C3+ ions, at 3 MV terminal potential. The first sensible spectra allowed for the pin-pointing of many persistent issues. This resulted in measurements with a precision better than 1 pMC, and current blank levels correspond to 12 half-lives of 14C or ∼68000 years. The radiocarbon sample preparation laboratory has reached production status. A brief outlook of the work towards the implementation of the measurement and chemical preparation protocols for radionuclides 10Be and 26Al is also summarised in the conclusion

Comparison of marginal accuracy of castings fabricated by conventional casting technique and accelerated casting technique: an in vitro study.

PubMed

Reddy, S Srikanth; Revathi, Kakkirala; Reddy, S Kranthikumar

2013-01-01

Conventional casting technique is time consuming when compared to accelerated casting technique. In this study, marginal accuracy of castings fabricated using accelerated and conventional casting technique was compared. 20 wax patterns were fabricated and the marginal discrepancy between the die and patterns were measured using Optical stereomicroscope. Ten wax patterns were used for Conventional casting and the rest for Accelerated casting. A Nickel-Chromium alloy was used for the casting. The castings were measured for marginal discrepancies and compared. Castings fabricated using Conventional casting technique showed less vertical marginal discrepancy than the castings fabricated by Accelerated casting technique. The values were statistically highly significant. Conventional casting technique produced better marginal accuracy when compared to Accelerated casting. The vertical marginal discrepancy produced by the Accelerated casting technique was well within the maximum clinical tolerance limits. Accelerated casting technique can be used to save lab time to fabricate clinical crowns with acceptable vertical marginal discrepancy.

Berkeley Lab - Materials Sciences Division

Science.gov Websites

Berkeley Lab Berkeley Lab A-Z Index Phone Book Jobs Search DOE Search MSD Go MSD - Materials Investigators Ager, Joel W » Alivisatos, A Paul » Altman, Ehud » Analytis, James » Anderson, Christopher  , Naomi » Gullikson, Eric M » Harris, Stephen J » Hasan, M. Zahid » Hellman, Frances » Helms, Brett A

Experiential Learning of Digital Communication Using LabVIEW

ERIC Educational Resources Information Center

Zhan, Wei; Porter, Jay R.; Morgan, Joseph A.

2014-01-01

This paper discusses the design and implementation of laboratories and course projects using LabVIEW in an instrumentation course. The pedagogical challenge is to enhance students' learning of digital communication using LabVIEW. LabVIEW was extensively used in the laboratory sessions, which better prepared students for the course projects. Two…

The Qweak experimental apparatus

NASA Astrophysics Data System (ADS)

Allison, T.; Anderson, M.; Androić, D.; Armstrong, D. S.; Asaturyan, A.; Averett, T.; Averill, R.; Balewski, J.; Beaufait, J.; Beminiwattha, R. S.; Benesch, J.; Benmokhtar, F.; Bessuille, J.; Birchall, J.; Bonnell, E.; Bowman, J. D.; Brindza, P.; Brown, D. B.; Carlini, R. D.; Cates, G. D.; Cavness, B.; Clark, G.; Cornejo, J. C.; Dusa, S. Covrig; Dalton, M. M.; Davis, C. A.; Dean, D. C.; Deconinck, W.; Diefenbach, J.; Dow, K.; Dowd, J. F.; Dunne, J. A.; Dutta, D.; Duvall, W. S.; Echols, J. R.; Elaasar, M.; Falk, W. R.; Finelli, K. D.; Finn, J. M.; Gaskell, D.; Gericke, M. T. W.; Grames, J.; Gray, V. M.; Grimm, K.; Guo, F.; Hansknecht, J.; Harrison, D. J.; Henderson, E.; Hoskins, J. R.; Ihloff, E.; Johnston, K.; Jones, D.; Jones, M.; Jones, R.; Kargiantoulakis, M.; Kelsey, J.; Khan, N.; King, P. M.; Korkmaz, E.; Kowalski, S.; Kubera, A.; Leacock, J.; Leckey, J. P.; Lee, A. R.; Lee, J. H.; Lee, L.; Liang, Y.; MacEwan, S.; Mack, D.; Magee, J. A.; Mahurin, R.; Mammei, J.; Martin, J. W.; McCreary, A.; McDonald, M. H.; McHugh, M. J.; Medeiros, P.; Meekins, D.; Mei, J.; Michaels, R.; Micherdzinska, A.; Mkrtchyan, A.; Mkrtchyan, H.; Morgan, N.; Musson, J.; Mesick, K. E.; Narayan, A.; Ndukum, L. Z.; Nelyubin, V.; Nuruzzaman; van Oers, W. T. H.; Opper, A. K.; Page, S. A.; Pan, J.; Paschke, K. D.; Phillips, S. K.; Pitt, M. L.; Poelker, M.; Rajotte, J. F.; Ramsay, W. D.; Roberts, W. R.; Roche, J.; Rose, P. W.; Sawatzky, B.; Seva, T.; Shabestari, M. H.; Silwal, R.; Simicevic, N.; Smith, G. R.; Sobczynski, S.; Solvignon, P.; Spayde, D. T.; Stokes, B.; Storey, D. W.; Subedi, A.; Subedi, R.; Suleiman, R.; Tadevosyan, V.; Tobias, W. A.; Tvaskis, V.; Urban, E.; Waidyawansa, B.; Wang, P.; Wells, S. P.; Wood, S. A.; Yang, S.; Zhamkochyan, S.; Zielinski, R. B.

2015-05-01

The Jefferson Lab Qweak experiment determined the weak charge of the proton by measuring the parity-violating elastic scattering asymmetry of longitudinally polarized electrons from an unpolarized liquid hydrogen target at small momentum transfer. A custom apparatus was designed for this experiment to meet the technical challenges presented by the smallest and most precise e → p asymmetry ever measured. Technical milestones were achieved at Jefferson Lab in target power, beam current, beam helicity reversal rate, polarimetry, detected rates, and control of helicity-correlated beam properties. The experiment employed 180 μA of 89% longitudinally polarized electrons whose helicity was reversed 960 times per second. The electrons were accelerated to 1.16 GeV and directed to a beamline with extensive instrumentation to measure helicity-correlated beam properties that can induce false asymmetries. Møller and Compton polarimetry were used to measure the electron beam polarization to better than 1%. The electron beam was incident on a 34.4 cm liquid hydrogen target. After passing through a triple collimator system, scattered electrons between 5.8° and 11.6° were bent in the toroidal magnetic field of a resistive copper-coil magnet. The electrons inside this acceptance were focused onto eight fused silica Cherenkov detectors arrayed symmetrically around the beam axis. A total scattered electron rate of about 7 GHz was incident on the detector array. The detectors were read out in integrating mode by custom-built low-noise pre-amplifiers and 18-bit sampling ADC modules. The momentum transfer Q2=0.025 GeV2 was determined using dedicated low-current (~ 100 pA) measurements with a set of drift chambers before (and a set of drift chambers and trigger scintillation counters after) the toroidal magnet.

Estimates of effects of residual acceleration on USML-1 experiments

NASA Technical Reports Server (NTRS)

Naumann, Robert J.

1995-01-01

The purpose of this study effort was to develop analytical models to describe the effects of residual accelerations on the experiments to be carried on the first U.S. Microgravity Lab mission (USML-1) and to test the accuracy of these models by comparing the pre-flight predicted effects with the post-flight measured effects. After surveying the experiments to be performed on USML-1, it became evident that the anticipated residual accelerations during the USML-1 mission were well below the threshold for most of the primary experiments and all of the secondary (Glovebox) experiments and that the only set of experiments that could provide quantifiable effects, and thus provide a definitive test of the analytical models, were the three melt growth experiments using the Bridgman-Stockbarger type Crystal Growth Furnace (CGF). This class of experiments is by far the most sensitive to low level quasi-steady accelerations that are unavoidable on space craft operating in low earth orbit. Because of this, they have been the drivers for the acceleration requirements imposed on the Space Station. Therefore, it is appropriate that the models on which these requirements are based are tested experimentally. Also, since solidification proceeds directionally over a long period of time, the solidified ingot provides a more or less continuous record of the effects from acceleration disturbances.

Practical Physics Labs: A Resource Manual.

ERIC Educational Resources Information Center

Goodwin, Peter

This resource manual focuses on physics labs that relate to the world around us and utilize simple equipment and situations. Forty-five laboratories are included that relate to thermodynamics, electricity, magnetism, dynamics, optics, wave transmission, centripetal force, and atomic physics. Each lab has three sections. The first section…

My Brother’s Keeper National Lab Week

NASA Image and Video Library

2016-03-02

Students in the My Brother’s Keeper program line the railings of an observation deck overlooking the Granular Mechanics and Regolith Operations Lab at NASA’s Kennedy Space Center in Florida. The spaceport is one of six NASA centers that participated in My Brother’s Keeper National Lab Week. The event is a nationwide effort to bring youth from underrepresented communities into federal labs and centers for hands-on activities, tours and inspirational speakers. Sixty students from the nearby cities of Orlando and Sanford visited Kennedy, where they toured the Vehicle Assembly Building, the Space Station Processing Facility and the center’s innovative Swamp Works Labs. The students also had a chance to meet and ask questions of a panel of subject matter experts from across Kennedy.

My Brother’s Keeper National Lab Week

NASA Image and Video Library

2016-03-02

Students in the My Brother’s Keeper program try out some of the machinery inside the Prototype Lab at NASA’s Kennedy Space Center. The Florida spaceport is one of six NASA centers that participated in My Brother’s Keeper National Lab Week. The event is a nationwide effort to bring youth from underrepresented communities into federal labs and centers for hands-on activities, tours and inspirational speakers. Sixty students from the nearby cities of Orlando and Sanford visited Kennedy, where they toured the Vehicle Assembly Building, the Space Station Processing Facility and the center’s innovative Swamp Works Labs. The students also had a chance to meet and ask questions of a panel of subject matter experts from across Kennedy.

My Brother’s Keeper National Lab Week

NASA Image and Video Library

2016-03-02

Mike Lane demonstrates a 3D scanner inside the NASA Kennedy Space Center Prototype Lab for students in the My Brother’s Keeper program. The Florida spaceport is one of six NASA centers that participated in My Brother’s Keeper National Lab Week. The event is a nationwide effort to bring youth from underrepresented communities into federal labs and centers for hands-on activities, tours and inspirational speakers. Sixty students from the nearby cities of Orlando and Sanford visited Kennedy, where they toured the Vehicle Assembly Building, the Space Station Processing Facility and the center’s innovative Swamp Works Labs. The students also had a chance to meet and ask questions of a panel of subject matter experts from across Kennedy.

My Brother’s Keeper National Lab Week

NASA Image and Video Library

2016-03-02

Harold (Russ) McAmis demonstrates machinery inside NASA Kennedy Space Center’s Prototype Lab for students in the My Brother’s Keeper program. The Florida spaceport is one of six NASA centers that participated in My Brother’s Keeper National Lab Week. The event is a nationwide effort to bring youth from underrepresented communities into federal labs and centers for hands-on activities, tours and inspirational speakers. Sixty students from the nearby cities of Orlando and Sanford visited Kennedy, where they toured the Vehicle Assembly Building, the Space Station Processing Facility and the center’s innovative Swamp Works Labs. The students also had a chance to meet and ask questions of a panel of subject matter experts from across Kennedy.

My Brother’s Keeper National Lab Week

NASA Image and Video Library

2016-03-02

Jose Nunez of NASA Kennedy Space Center’s Exploration Research and Technology Programs talks to students in the My Brother’s Keeper program outside the Florida spaceport’s Swamp Works Lab. Kennedy is one of six NASA centers that participated in My Brother’s Keeper National Lab Week. The event is a nationwide effort to bring youth from underrepresented communities into federal labs and centers for hands-on activities, tours and inspirational speakers. Sixty students from the nearby cities of Orlando and Sanford visited Kennedy, where they toured the Vehicle Assembly Building, the Space Station Processing Facility and the center’s innovative Swamp Works Labs. The students also had a chance to meet and ask questions of a panel of subject matter experts from across Kennedy.

Baseball Physics: A New Mechanics Lab

NASA Astrophysics Data System (ADS)

Wagoner, Kasey; Flanagan, Daniel

2018-05-01

The game of baseball provides an interesting laboratory for experimenting with mechanical phenomena (there are many good examples in The Physics Teacher, available on Professor Alan Nathan's website, and discussed in Physics of Baseball & Softball). We have developed a lab, for an introductory-level physics course, that investigates many of these phenomena. The lab uses inexpensive, readily available equipment such as wooden baseball bats, baseballs, and actual Major League Baseball data. By the end of the lab, students have revisited many concepts they learned earlier in the semester and come away with an understanding of how to put seemingly disparate ideas together to analyze a fun sport.

Teaching Chemistry Lab Safety through Comics

NASA Astrophysics Data System (ADS)

di Raddo, Pasquale

2006-04-01

As a means for raising students' interest in aspects pertaining to chemistry lab safety, this article presents a novel approach to teaching this important subject. Comic book lab scenes that involve fictional characters familiar to many students are presented and discussed as to the safety concerns represented in those images. These are discussed in a safety prelab session. For the sake of comparison, students are then shown images taken from current chemistry journals of safety-conscious contemporary chemists at work in their labs. Finally the need to adhere to copyright regulations for the use of the images is discussed so as to increase students' awareness of academic honesty and copyright issues.

Energy-Recovery Linacs for Commercial Radioisotope Production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Rolland Paul

Most radioisotopes are produced by nuclear reactors or positive ion accelerators, which are expensive to construct and to operate. Photonuclear reactions using bremsstrahlung photon beams from less-expensive electron linacs can generate isotopes of critical interest, but much of the beam energy in a conventional electron linac is dumped at high energy, making unwanted radioactivation. The largest part of this radioactivation may be completely eliminated by applying energy recovery linac technology to the problem with an additional benefit that the energy cost to produce a given amount of isotope is reduced. Consequently, a Superconducting Radio Frequency (SRF) Energy Recovery Linac (ERL)more » is a path to a more diverse and reliable domestic supply of short-lived, high-value, high-demand isotopes at a cost lower than that of isotopes produced by reactors or positive-ion accelerators. A Jefferson Lab approach to this problem involves a thin photon production radiator, which allows the electron beam to recirculate through rf cavities so the beam energy can be recovered while the spent electrons are extracted and absorbed at a low enough energy to minimize unwanted radioactivation. The thicker isotope photoproduction target is not in the beam. MuPlus, with Jefferson Lab and Niowave, proposed to extend this ERL technology to the commercial world of radioisotope production. In Phase I we demonstrated that 1) the ERL advantage for producing radioisotopes is at high energies (~100 MeV), 2) the range of acceptable radiator thickness is narrow (too thin and there is no advantage relative to other methods and too thick means energy recovery is too difficult), 3) using optics techniques developed under an earlier STTR for collider low beta designs greatly improves the fraction of beam energy that can be recovered (patent pending), 4) many potentially useful radioisotopes can be made with this ERL technique that have never before been available in significant commercial

Hydrogel Beads: The New Slime Lab?

ERIC Educational Resources Information Center

Brockway, Debra; Libera, Matthew; Welner, Heidi

2011-01-01

Creating slime fascinates students. Unfortunately, though intrigue is at its peak, the educational aspect of this activity is often minimal. This article describes a chemistry lab that closely relates to the slime lab and allows high school students to explore the concepts of chemical bonding, properties, and replacement reactions. It involves the…

Cryogenic Plants for SRF Linacs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Arenius, Dana M.

2014-12-01

Review of the types of considerations that go into cryoplant design. Arenius is a world expert on this topic and has led the completion of the upgraded cryoplant at Jefferson Lab, and has recently provided substantial input on this question to the new LCLS II project.

Interactive, Online, Adsorption Lab to Support Discovery of the Scientific Process

NASA Astrophysics Data System (ADS)

Carroll, K. C.; Ulery, A. L.; Chamberlin, B.; Dettmer, A.

2014-12-01

Science students require more than methods practice in lab activities; they must gain an understanding of the application of the scientific process through lab work. Large classes, time constraints, and funding may limit student access to science labs, denying students access to the types of experiential learning needed to motivate and develop new scientists. Interactive, discovery-based computer simulations and virtual labs provide an alternative, low-risk opportunity for learners to engage in lab processes and activities. Students can conduct experiments, collect data, draw conclusions, and even abort a session. We have developed an online virtual lab, through which students can interactively develop as scientists as they learn about scientific concepts, lab equipment, and proper lab techniques. Our first lab topic is adsorption of chemicals to soil, but the methodology is transferrable to other topics. In addition to learning the specific procedures involved in each lab, the online activities will prompt exploration and practice in key scientific and mathematical concepts, such as unit conversion, significant digits, assessing risks, evaluating bias, and assessing quantity and quality of data. These labs are not designed to replace traditional lab instruction, but to supplement instruction on challenging or particularly time-consuming concepts. To complement classroom instruction, students can engage in a lab experience outside the lab and over a shorter time period than often required with real-world adsorption studies. More importantly, students can reflect, discuss, review, and even fail at their lab experience as part of the process to see why natural processes and scientific approaches work the way they do. Our Media Productions team has completed a series of online digital labs available at virtuallabs.nmsu.edu and scienceofsoil.com, and these virtual labs are being integrated into coursework to evaluate changes in student learning.

Bituminous Mixtures Lab

DOT National Transportation Integrated Search

2002-07-25

The Bituminous Mixtures Laboratory (BML) specializes in the research of asphalt pavement mixtures. This lab supports FHWA's efforts to develop, evaluate and improve materials, mixture design technology and performance-based tests for asphalt paving m...

Measurement of the Elastic Ep Cross Section at Q2 = 0.66, 1.10, 1.51 and 1.65 Gev2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yang

The nucleon form factors have been investigated by physicists for decades because of their fundamental importance. The world data of the proton magnetic form factor GMp has been focused on Q2 lower than 5 GeV2 and they have large uncertainties at higher Q2. Jefferson Lab experiment E12-07-108 aims to improve the accuracy of the e ? p elastic cross section to better than 2% over a Q2 range of 7 ? 14 GeV2. From 2015 to 2016, the e ? p elastic cross section was measured over a wide range of Q2 from 0.66 ? 12.56 GeV2 at the Thomasmore » Jefferson National Accelerator Facility in Virginia, USA. An unpolarized electron beam was scattered o? a cryogenic hydrogen target and the scattered electron was detected in the high resolution spectrometers. This thesis focuses on the cross section calculations of the data taken in the spring of 2015, where Q2 = 0.66, 1.10, 1.51 and 1.66 GeV2. At Q2 = 0.66 GeV2, an uncertainty < 3% was achieved and < 5% was achieved for the other three Q2 at the moment. The results were compared with the world data and the good agreement provides confidence for the experimental measurements at higher Q2.« less

Instrument design optimization with computational methods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore, Michael H.

Using Finite Element Analysis to approximate the solution of differential equations, two different instruments in experimental Hall C at the Thomas Jefferson National Accelerator Facility are analyzed. The time dependence of density uctuations from the liquid hydrogen (LH2) target used in the Q weak experiment (2011-2012) are studied with Computational Fluid Dynamics (CFD) and the simulation results compared to data from the experiment. The 2.5 kW liquid hydrogen target was the highest power LH2 target in the world and the first to be designed with CFD at Jefferson Lab. The first complete magnetic field simulation of the Super High Momentummore » Spectrometer (SHMS) is presented with a focus on primary electron beam deflection downstream of the target. The SHMS consists of a superconducting horizontal bending magnet (HB) and three superconducting quadrupole magnets. The HB allows particles scattered at an angle of 5:5 deg to the beam line to be steered into the quadrupole magnets which make up the optics of the spectrometer. Without mitigation, remnant fields from the SHMS may steer the unscattered beam outside of the acceptable envelope on the beam dump and limit beam operations at small scattering angles. A solution is proposed using optimal placement of a minimal amount of shielding iron around the beam line.« less

Seeing an Old Lab in a New Light: Transforming a Traditional Optics Lab into Full Guided Inquiry

ERIC Educational Resources Information Center

Maley, Tim; Stoll, Will; Demir, Kadir

2013-01-01

This paper describes the authors' experiences transforming a "cookbook" lab into an inquiry-based investigation and the powerful effect the inquiry-oriented lab had on our students' understanding of lenses. We found the inquiry-oriented approach led to richer interactions between students as well as a deeper conceptual…

My Brother’s Keeper National Lab Week

NASA Image and Video Library

2016-03-02

Students in the My Brother’s Keeper program watch as Jose Nunez of NASA Kennedy Space Center’s Exploration Research and Technology Programs demonstrates some of the hardware in the Electrostatic and Surface Physics Lab at the Florida spaceport. Kennedy is one of six NASA centers that participated in My Brother’s Keeper National Lab Week. The event is a nationwide effort to bring youth from underrepresented communities into federal labs and centers for hands-on activities, tours and inspirational speakers. Sixty students from the nearby cities of Orlando and Sanford visited Kennedy, where they toured the Vehicle Assembly Building, the Space Station Processing Facility and the center’s innovative Swamp Works Labs. The students also had a chance to meet and ask questions of a panel of subject matter experts from across Kennedy.

My Brother’s Keeper National Lab Week

NASA Image and Video Library

2016-03-02

Students in the My Brother’s Keeper program listen as Jose Nunez of NASA Kennedy Space Center’s Exploration Research and Technology Programs explains some of the hardware in the Electrostatic and Surface Physics Lab at the Florida spaceport. Kennedy is one of six NASA centers that participated in My Brother’s Keeper National Lab Week. The event is a nationwide effort to bring youth from underrepresented communities into federal labs and centers for hands-on activities, tours and inspirational speakers. Sixty students from the nearby cities of Orlando and Sanford visited Kennedy, where they toured the Vehicle Assembly Building, the Space Station Processing Facility and the center’s innovative Swamp Works Labs. The students also had a chance to meet and ask questions of a panel of subject matter experts from across Kennedy.

GeoLab: A Geological Workstation for Future Missions

NASA Technical Reports Server (NTRS)

Evans, Cynthia; Calaway, Michael; Bell, Mary Sue; Li, Zheng; Tong, Shuo; Zhong, Ye; Dahiwala, Ravi

2014-01-01

The GeoLab glovebox was, until November 2012, fully integrated into NASA's Deep Space Habitat (DSH) Analog Testbed. The conceptual design for GeoLab came from several sources, including current research instruments (Microgravity Science Glovebox) used on the International Space Station, existing Astromaterials Curation Laboratory hardware and clean room procedures, and mission scenarios developed for earlier programs. GeoLab allowed NASA scientists to test science operations related to contained sample examination during simulated exploration missions. The team demonstrated science operations that enhance theThe GeoLab glovebox was, until November 2012, fully integrated into NASA's Deep Space Habitat (DSH) Analog Testbed. The conceptual design for GeoLab came from several sources, including current research instruments (Microgravity Science Glovebox) used on the International Space Station, existing Astromaterials Curation Laboratory hardware and clean room procedures, and mission scenarios developed for earlier programs. GeoLab allowed NASA scientists to test science operations related to contained sample examination during simulated exploration missions. The team demonstrated science operations that enhance the early scientific returns from future missions and ensure that the best samples are selected for Earth return. The facility was also designed to foster the development of instrument technology. Since 2009, when GeoLab design and construction began, the GeoLab team [a group of scientists from the Astromaterials Acquisition and Curation Office within the Astromaterials Research and Exploration Science (ARES) Directorate at JSC] has progressively developed and reconfigured the GeoLab hardware and software interfaces and developed test objectives, which were to 1) determine requirements and strategies for sample handling and prioritization for geological operations on other planetary surfaces, 2) assess the scientific contribution of selective in-situ sample

Debris flows from failures Neoglacial-age moraine dams in the Three Sisters and Mount Jefferson wilderness areas, Oregon

USGS Publications Warehouse

O'Connor, J. E.; Hardison, J.H.; Costa, J.E.

2001-01-01

The highest concentration of lakes dammed by Neoglacial moraines in the conterminous United States is in the Mount Jefferson and Three Sisters Wilderness Areas in central Oregon. Between 1930 and 1980, breakouts of these lakes have resulted in 11 debris flows. The settings and sequences of events leading to breaching and the downstream flow behavior of the resulting debris flows provide guidance on the likelihood and magnitude of future lake breakouts and debris flows.

Germany-US Nuclear Theory Exchange Program for QCD Studies of Hadrons & Nuclei 'GAUSTEQ'

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dudek, Jozef; Melnitchouk, Wally

GAUSTEQ was a Germany-U.S. exchange program in nuclear theory whose purpose was to focus research efforts on QCD studies of hadrons and nuclei, centered around the current and future research programs of Jefferson Lab and the Gesellschaft fur Schwerionenforschung (GSI) in Germany. GAUSTEQ provided travel support for theoretical physicists at US institutions conducting collaborative research with physicists in Germany. GSI (with its Darmstadt and Helmholtz Institute Mainz braches) served as the German “hub” for visits of U.S. physicists, while Jefferson Lab served as the corresponding “hub” for visits of German physicists visiting U.S. institutions through the reciprocal GUSTEHP (German-US Theorymore » Exchange in Hadron Physics) program. GAUSTEQ was funded by the Office of Nuclear Physics of the U.S. Department of Energy, under Contract No.DE-SC0006758 and officially managed through Old Dominion University in Norfolk, Virginia. The program ran between 2011 and 2015.« less

QCD Evolution 2016

NASA Astrophysics Data System (ADS)

The QCD Evolution 2016 workshop was held at the National Institute for Subatomic Physics (Nikhef) in Amsterdam, May 30 - June 3, 2016. The workshop is a continuation of a series of workshops held during five consecutive years, in 2011, 2012, 2013, 2015 at Jefferson Lab, and in 2014 in Santa Fe, NM. With the rapid developments in our understanding of the evolution of parton distributions including low-x, TMDs, GPDs, higher-twist correlation functions, and the associated progress in perturbative QCD, lattice QCD and effective field theory techniques, we look forward to yet another exciting meeting in 2016. The program of QCD Evolution 2016 will pay special attention to the topics of importance for ongoing experiments, in the full range from Jefferson Lab energies to LHC energies or future experiments such as a future Electron Ion Collider, recently recommended as a highest priority in U.S. Department of Energy's 2015 Long Range Plan for Nuclear Science.

Supercharging Lessons with a Virtual Lab

ERIC Educational Resources Information Center

Stewart, Jefferson; Vincent, Daniel

2013-01-01

The authors describes their experiences incorporating the virtual lab into a simple circuit lesson during an energy unit in a sixth-grade class. The lesson included a hands-on group experiment using wire, batteries, and light bulbs to make a circuit and an online simulation, using a virtual lab. Class discussions, student inquiries, and the study…

Magnetic Viscous Drag for Friction Labs

ERIC Educational Resources Information Center

Gaffney, Chris; Catching, Adam

2016-01-01

The typical friction lab performed in introductory mechanics courses is usually not the favorite of either the student or the instructor. The measurements are not all that easy to make, and reproducibility is usually a troublesome issue. This paper describes the augmentation of such a friction lab with a study of the viscous drag on a magnet…

Berkeley Lab Scientist Named MacArthur "Genius" Fellow for Audio

Science.gov Websites

Preservation Research | Berkeley Lab Berkeley Lab A-Z Index Directory Submit Web People Navigation Berkeley Lab Search Submit Web People Close About the Lab Leadership/Organization Calendar News to digitally recover a 128-year-old recording of Alexander Graham Bell's voice, enabling people to

The Impact of Court-Ordered Desegregation on Student Enrollment and Residential Patterns in the Jefferson County Kentucky Public School District, Final Report.

ERIC Educational Resources Information Center

Cunningham, George K.; Husk, William L.

After reviewing the literature on school desegregation and the background of the comprehensive metropolitan school desegregation plan implemented in Louisville and Jefferson County in 1975, this report analyzes school enrollment and residential changes in the years after the plan was implemented. Data are presented for public and non-public school…

Numerical Nudging: Using an Accelerating Score to Enhance Performance.

PubMed

Shen, Luxi; Hsee, Christopher K

2017-08-01

People often encounter inherently meaningless numbers, such as scores in health apps or video games, that increase as they take actions. This research explored how the pattern of change in such numbers influences performance. We found that the key factor is acceleration-namely, whether the number increases at an increasing velocity. Six experiments in both the lab and the field showed that people performed better on an ongoing task if they were presented with a number that increased at an increasing velocity than if they were not presented with such a number or if they were presented with a number that increased at a decreasing or constant velocity. This acceleration effect occurred regardless of the absolute magnitude or the absolute velocity of the number, and even when the number was not tied to any specific rewards. This research shows the potential of numerical nudging-using inherently meaningless numbers to strategically alter behaviors-and is especially relevant in the present age of digital devices.

Flexible HVAC System for Lab or Classroom.

ERIC Educational Resources Information Center

Friedan, Jonathan

2001-01-01

Discusses an effort to design a heating, ventilation, and air conditioning system flexible enough to accommodate an easy conversion of classrooms to laboratories and dry labs to wet labs. The design's energy efficiency and operations and maintenance are examined. (GR)

Electroproduction of Photons and of Pawns on the Proton in Quadrimoment of Transfer Q 2=1.0GeV 2. Measure Cross Sections and Extraction of Polarizabilities Generalities; Electroproduction de Photons et de Pions sur le Proton au Quadrimoment de Transfert Q 2=1.0GeV 2. Mesure des Sections Efficaces et Extraction des Polarisabilites Generalisees (in French)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laveissiere, Geraud

In hadronic physics, the nucleon structure and the quarks confinement are still topical issues. The neutral pion electroproduction and virtual Compton scattering (VCS) reactions allow us to access new observables that describe this structure. This work is focused on the VCS experiment performed at Jefferson Lab in 1998.

Gender Comparisons of Young Physicians' Perceptions of Their Medical Education, Professional Life, and Practice: A Follow-Up Study of Jefferson Medical College Graduates.

ERIC Educational Resources Information Center

Hojat, Mohammadreza; And Others

1995-01-01

A survey of 530 male and 137 female graduates of Jefferson Medical College (Pennsylvania) found numerous gender differences in their assessments of selected areas of the medical school curriculum, issues of medical practice and professional life, and specialty choices, professional activities, and research productivity. (Author/MSE)

Assessing Usage and Maximizing Finance Lab Impact: A Case Exploration

ERIC Educational Resources Information Center

Noguera, Magdy; Budden, Michael Craig; Silva, Alberto

2011-01-01

This paper reports the results of a survey conducted to assess students' usage and perceptions of a finance lab. Finance labs differ from simple computer labs as they typically contain data boards, streaming market quotes, terminals and software that allow for real-time financial analyses. Despite the fact that such labs represent significant and…

Design of Inquiry-Oriented Science Labs: Impacts on Students' Attitudes

ERIC Educational Resources Information Center

Baseya, J. M.; Francis, C. D.

2011-01-01

Background: Changes in lab style can lead to differences in learning. Two inquiry-oriented lab styles are guided inquiry (GI) and problem-based (PB). Students' attitudes towards lab are important to consider when choosing between GI and PB styles during curriculum design. Purpose: We examined the degree to which lab experiences are explained by a…

Designing virtual science labs for the Islamic Academy of Delaware

NASA Astrophysics Data System (ADS)

AlZahrani, Nada Saeed

Science education is a basic part of the curriculum in modern day classrooms. Instructional approaches to science education can take many forms but hands-on application of theory via science laboratory activities for the learner is common. Not all schools have the resources to provide the laboratory environment necessary for hands-on application of science theory. Some settings rely on technology to provide a virtual laboratory experience instead. The Islamic Academy of Delaware (IAD), a typical community-based organization, was formed to support and meet the essential needs of the Muslim community of Delaware. IAD provides science education as part of the overall curriculum, but cannot provide laboratory activities as part of the science program. Virtual science labs may be a successful model for students at IAD. This study was conducted to investigate the potential of implementing virtual science labs at IAD and to develop an implementation plan for integrating the virtual labs. The literature has shown us that the lab experience is a valuable part of the science curriculum (NBPTS, 2013, Wolf, 2010, National Research Council, 1997 & 2012). The National Research Council (2012) stressed the inclusion of laboratory investigations in the science curriculum. The literature also supports the use of virtual labs as an effective substitute for classroom labs (Babateen, 2011; National Science Teachers Association, 2008). Pyatt and Simms (2011) found evidence that virtual labs were as good, if not better than physical lab experiences in some respects. Although not identical in experience to a live lab, the virtual lab has been shown to provide the student with an effective laboratory experience in situations where the live lab is not possible. The results of the IAD teacher interviews indicate that the teachers are well-prepared for, and supportive of, the implementation of virtual labs to improve the science education curriculum. The investigator believes that with the

Transforming the advanced lab: Part I - Learning goals

NASA Astrophysics Data System (ADS)

Zwickl, Benjamin; Finkelstein, Noah; Lewandowski, H. J.

2012-02-01

Within the physics education research community relatively little attention has been given to laboratory courses, especially at the upper-division undergraduate level. As part of transforming our senior-level Optics and Modern Physics Lab at the University of Colorado Boulder we are developing learning goals, revising curricula, and creating assessments. In this paper, we report on the establishment of our learning goals and a surrounding framework that have emerged from discussions with a wide variety of faculty, from a review of the literature on labs, and from identifying the goals of existing lab courses. Our goals go beyond those of specific physics content and apparatus, allowing instructors to personalize them to their contexts. We report on four broad themes and associated learning goals: Modeling (math-physics-data connection, statistical error analysis, systematic error, modeling of engineered "black boxes"), Design (of experiments, apparatus, programs, troubleshooting), Communication, and Technical Lab Skills (computer-aided data analysis, LabVIEW, test and measurement equipment).

Student Plagiarism and Faculty Responsibility in Undergraduate Engineering Labs

ERIC Educational Resources Information Center

Parameswaran, Ashvin; Devi, Poornima

2006-01-01

In undergraduate engineering labs, lab reports are routinely copied. By ignoring this form of plagiarism, teaching assistants and lab technicians neglect their role responsibility. By designing courses that facilitate it, however inadvertently, professors neglect their causal responsibility. Using the case of one university, we show via interviews…

Smartphones - the Geophysics Lab in Your Students' Pocket

NASA Astrophysics Data System (ADS)

Salaree, A.; Stein, S.; Saloor, N.; Elling, R. P.

2017-12-01

Many interesting topics are hard to demonstrate in geophysics classes without costly equipment and logistic hassles. For instance, the speed of P-waves in the Earth's crust is usually calculated using printed seismic sections from published studies, giving students little insight into the recording process. This is mainly due to the complex, costly, and weather-dependent logistics of conducting seismic reflection experiments using arrays of - either purchased or borrowed - expensive seismometers and recording units. Smartphones, which students own and are (perhaps unduly) comfortable with, have many otherwise expensive instruments as built-in sensors. These instruments are nifty tools that make labs easier, faster, and more fun. We use smartphones in several labs in an introductory geophysics class. In one, students use their phones to measure the latitude and longitude of a point on campus. Combining the data shows a nice spread of positions illustrating the precision of measurements, spatial trends in the scatter, and even differences between Android and iPhone data. Hence concepts about data that are often presented with ideal theoretical examples emerge from the students' measurements. Another uses the phones' accelerometers and available software to measure the speed of P-waves using a linear array of smartphones/seismometers along a table, similar to the procedure used in reflection seismology. In a third, students used their smartphones in an elevator to measure the acceleration of gravity in a moving reference frame, and thus explore key concepts that arise in many geophysical applications. These three applications illustrate the potential for using smartphones in a wide variety of geophysics teaching, much as their value is being increasingly recognized in other educational applications. Here are some links to an instructions document and a video from the seismic experiment: Instructions: http://www.earth.northwestern.edu/ amir/202/smartphone

Teaching And Training Tools For The Undergraduate: Experience With A Rebuilt AN-400 Accelerator

NASA Astrophysics Data System (ADS)

Roberts, Andrew D.

2011-06-01

There is an increasingly recognized need for people trained in a broad range of applied nuclear science techniques, indicated by reports from the American Physical Society and elsewhere. Anecdotal evidence suggests that opportunities for hands-on training with small particle accelerators have diminished in the US, as development programs established in the 1960's and 1970's have been decommissioned over recent decades. Despite the reduced interest in the use of low energy accelerators in fundamental research, these machines can offer a powerful platform for bringing unique training opportunities to the undergraduate curriculum in nuclear physics, engineering and technology. We report here on the new MSU Applied Nuclear Science Lab, centered around the rebuild of an AN400 electrostatic accelerator. This machine is run entirely by undergraduate students under faculty supervision, allowing a great deal of freedom in its use without restrictions from graduate or external project demands.

ISHN Ion Source Control System. First Steps Toward an EPICS Based ESS-Bilbao Accelerator Control System

NASA Astrophysics Data System (ADS)

Eguiraun, M.; Jugo, J.; Arredondo, I.; del Campo, M.; Feuchtwanger, J.; Etxebarria, V.; Bermejo, F. J.

2013-04-01

ISHN (Ion Source Hydrogen Negative) consists of a Penning type ion source in operation at ESS-Bilbao facilities. From the control point of view, this source is representative of the first steps and decisions taken towards the general control architecture of the whole accelerator to be built. The ISHN main control system is based on a PXI architecture, under a real-time controller which is programmed using LabVIEW. This system, with additional elements, is connected to the general control system. The whole system is based on EPICS for the control network, and the modularization of the communication layers of the accelerator plays an important role in the proposed control architecture.