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127 results on '"Hansknecht J"'

1. The Continuous Electron Beam Accelerator Facility at 12 GeV

Author

Adderley, P. A., Ahmed, S., Allison, T., Bachimanchi, R., Baggett, K., BastaniNejad, M., Bevins, B., Bevins, M., Bickley, M., Bodenstein, R. M., Bogacz, S. A., Bruker, M., Burrill, A., Cardman, L., Creel, J., Chao, Y. -C., Cheng, G., Ciovati, G., Chattopadhyay, S., Clark, J., Clemens, W. A., Croke, G., Daly, E., Davis, G. K., Delayen, J., De Silva, S. U., Dickson, R., Diaz, M., Drury, M., Doolittle, L., Douglas, D., Feldl, E., Fischer, J., Freyberger, A., Ganni, V., Geng, R. L., Ginsburg, C., Gomez, J., Grames, J., Gubeli, J., Guo, J., Hannon, F., Hansknecht, J., Harwood, L., Henry, J., Hernandez-Garcia, C., Higgins, S., Higinbotham, D., Hofler, A. S., Hiatt, T., Hogan, J., Hovater, C., Hutton, A., Jones, C., Jordan, K., Joyce, M., Kazimi, R., Keesee, M., Kelley, M. J., Keppel, C., Kimber, A., King, L., Kjeldsen, P., Kneisel, P., Koval, J., Krafft, G. A., Lahti, G., Larrieu, T., Lauze, R., Leemann, C., Legg, R., Li, R., Lin, F., Machie, D., Mammosser, J., Macha, K., Mahoney, K., Marhauser, F., Mastracci, B., Matalevich, J., McCarter, J., McCaughan, M., Merminga, L., Michaud, R., Morozov, V., Mounts, C., Musson, J., Nelson, R., Oren, W., Overton, R. B., Palacios-Serrano, G., Park, H. -K., Phillips, L., Philip, S., Pilat, F., Plawski, T., Poelker, M., Powers, P., Powers, T., Preble, J., Reilly, T., Rimmer, R., Reece, C., Robertson, H., Roblin, Y., Rode, C., Satogata, T., Seidman, D. J., Seryi, A., Shabalina, A., Shin, I., Slominski, R., Slominski, C., Spata, M., Spell, D., Spradlin, J., Stirbet, M., Stutzman, M. L., Suhring, S., Surles-Law, K., Suleiman, R., Tennant, C., Tian, H., Turner, D., Tiefenback, M., Trofimova, O., Valente, A. -M., Wang, H., Wang, Y., White, K., Whitlatch, C., Whitlatch, T., Wiseman, M., Wissman, M. J., Wu, G., Yang, S., Yunn, B., Zhang, S., and Zhang, Y.

Subjects
Physics - Accelerator Physics, Nuclear Experiment
Abstract

This review paper describes the energy-upgraded CEBAF accelerator. This superconducting linac has achieved 12 GeV beam energy by adding 11 new high-performance cryomodules containing eighty-eight superconducting cavities that have operated CW at an average accelerating gradient of 20 MV/m. After reviewing the attributes and performance of the previous 6 GeV CEBAF accelerator, we discuss the upgraded CEBAF accelerator system in detail with particular attention paid to the new beam acceleration systems. In addition to doubling the acceleration in each linac, the upgrade included improving the beam recirculation magnets, adding more helium cooling capacity to allow the newly installed modules to run cold, adding a new experimental hall, and improving numerous other accelerator components. We review several of the techniques deployed to operate and analyze the accelerator performance, and document system operating experience and performance. In the final portion of the document, we present much of the current planning regarding projects to improve accelerator performance and enhance operating margins, and our plans for ensuring CEBAF operates reliably into the future. For the benefit of potential users of CEBAF, the performance and quality measures for beam delivered to each of the experimental halls is summarized in the appendix., Comment: 66 pages, 73 figures, 21 tables

Published
2024
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2. Recent results from the G0 experiment

Author

Roos P., Roche J., Ramsay W.D., Quinn B., Poelker M., Pitt M.L., Pillot P., Phillips S.K., Pate S.F., Papavassiliou V., Page S.A., van Oers W.T.H., Muether M., Mkrtchyan H., Mihovilovic M., Micherdzinska A., McKeown R.D., Martin J.W., Mammei J., Lung A., Liu J., Lee L., Kox S., Korsch W., King P.M., Jones M., Horn T., Hansknecht J., Guillard G., Grames J., Gericke M.T.W., Gaskell D., Furget C., Franklin G., Flores G., Davis C.A., Ellis C., Coppens A., Chao Y.-C., Capuano C.L., Breuer H., Bosted P., Birchall J., Benmokhtar F., Bimbot L., Benesch J., Beise E.J., Beck D.H., Bailey S.L., Arvieux J., Armstrong D.S., Androić D., Real J.S., Schaub J., Seva T., Simicevic N., Smith G.R., Spayde D.T., Stutzman M., Suleiman R., Tadevosyan V., Versteegen M., Voutier E., Vulcan W., Wells S.P., Williamson S.E., and Wood S.A.

Subjects
Physics, QC1-999
Abstract

We have measured parity violating asymmetries in elastic electron-proton and quasi-elastic electrondeuteron scattering at backward electron angle. These measurements have been done at two momentum transfers : Q2 = 0.22 and 0.63 (GeV/c)2 . Together with our previous forward angle measurement [1], we can extract strange quark contributions to the electromagnetic form factors of the nucleon, as well as nucleon axial form factor coming from the neutral weak interaction. The results indicate a strange quark magnetic contribution close to zero at these Q2 , and a possible non zero strange quark electric contribution for the high Q2 . The first Q2 behavior measurement of the nucleon axial form factor in elastic electron scattering shows a good agreement with radiative corrections calculated at Q2 = 0 and with a dipole form using the axial mass determined in neutrino scattering.

Published
2010
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4. Production of highly-polarized positrons using polarized electrons at MeV energies

Author

Abbott, D., Adderley, P., Adeyemi, A., Aguilera, P., Ali, M., Areti, H., Baylac, M., Benesch, J., Bosson, G., Cade, B., Camsonne, A., Cardman, L. S., Clark, J., Cole, P., Covert, S., Cuevas, C., Dadoun, O., Dale, D., Dong, H., Dumas, J., Fanchini, E., Forest, T., Forman, E., Freyberger, A., Froidefond, E., Golge, S., Grames, J., Guèye, P., Hansknecht, J., Harrell, P., Hoskins, J., Hyde, C., Josey, B., Kazimi, R., Kim, Y., Machie, D., Mahoney, K., Mammei, R., Marton, M., McCarter, J., McCaughan, M., McHugh, M., McNulty, D., Mesick, K. E., Michaelides, T., Michaels, R., Moffit, B., Moser, D., Camacho, C. Muñoz, Muraz, J. -F., Opper, A., Poelker, M., Réal, J. -S., Richardson, L., Setiniyaz, S., Stutzman, M., Suleiman, R., Tennant, C., Tsai, C., Turner, D., Ungaro, M., Variola, A., Voutier, E., Wang, Y., and Zhang, Y.

Subjects
Physics - Accelerator Physics, High Energy Physics - Experiment, Nuclear Experiment
Abstract

The Polarized Electrons for Polarized Positrons experiment at the injector of the Continuous Electron Beam Accelerator Facility has demonstrated for the first time the efficient transfer of polarization from electrons to positrons produced by the polarized bremsstrahlung radiation induced by a polarized electron beam in a high-$Z$ target. Positron polarization up to 82\% have been measured for an initial electron beam momentum of 8.19~MeV/$c$, limited only by the electron beam polarization. This technique extends polarized positron capabilities from GeV to MeV electron beams, and opens access to polarized positron beam physics to a wide community., Comment: 5 pages, 4 figures

Published
2016
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5. The Q_weak Experimental Apparatus

Author

Qweak Collaboration, Allison, T., Anderson, M., Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T. D., Averill, R., Balewski, J., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Bessuille, J., Birchall, J., Bonnell, E., Bowman, J., 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., and Zielinski, R. B.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment, Physics - Accelerator Physics
Abstract

The Jefferson Lab Q_weak 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 ${\vec{e}}$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 microA 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. Moller 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 degrees and 11.6 degrees were bent in the toroidal magnetic field of a resistive copper-coil magnet. The electrons inside this acceptance were focused onto eight fused silica Cerenkov 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 Q^2 = 0.025 GeV^2 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., Comment: 48 pages, 36 figures. Accepted by Nuclear Instruments and Methods A

Published
2014

6. First Measurement of the Neutral Current Excitation of the Delta Resonance on a Proton Target

Author

G0 Collaboration, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. -C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Grames, J., Gericke, M. T. W., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. -S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., and Wood, S. A.

Subjects
Nuclear Experiment
Abstract

The parity-violating asymmetry arising from inelastic electron-nucleon scattering at backward angle (~95 degrees) near the Delta(1232) resonance has been measured using a hydrogen target. From this asymmetry, we extracted the axial transition form factor G^A_{N\Delta}, a function of the axial Adler form factors C^A_i. Though G^A_{N\Delta} has been previously studied using charged current reactions, this is the first measurement of the weak neutral current excitation of the Delta using a proton target. For Q^2 = 0.34 (GeV/c)^2 and W = 1.18 GeV, the asymmetry was measured to be -33.4 \pm (5.3)_{stat} \pm (5.1)_{sys} ppm. The value of G^A_{N\Delta} determined from the hydrogen asymmetry was -0.05 \pm (0.35)_{stat} \pm (0.34)_{sys} \pm (0.06)_{theory}. These findings agree within errors with theoretical predictions for both the total asymmetry and the form factor. In addition to the hydrogen measurement, the asymmetry was measured at the same kinematics using a deuterium target. The asymmetry for deuterium was determined to be -43.6 \pm (14.6)_{stat} \pm (6.2)_{sys} ppm., Comment: 8 pages, 3 figures, submitted to Physics Letters B

Published
2012

7. New Measurements of the Transverse Beam Asymmetry for Elastic Electron Scattering from Selected Nuclei

Author

HAPPEX, The, Collaborations, PREX, Abrahamyan, S., Acha, A., Afanasev, A., Ahmed, Z., Albataineh, H., Aniol, K., Armstrong, D. S., Armstrong, W., Arrington, J., Averett, T., Babineau, B., Bailey, S. L., Barber, J., Barbieri, A., Beck, A., Bellini, V., Beminiwattha, R., Benaoum, H., Benesch, J., Benmokhtar, F., Bertin, P., Bielarski, T., Boeglin, W., Bosted, P., Butaru, F., Burtin, E., Cahoon, J., Camsonne, A., Canan, M., Carter, P., Chang, C. C., Cates, G. D., Chao, Y. C., Chen, C., Chen, J. P., Choi, Seonho, Chudakov, E., Cisbani, E., Craver, B., Cusanno, F., Dalton, M. M., De Leo, R., de Jager, K., Deconinck, W., Decowski, P., Deepa, D., Deng, X., Deur, A., Dutta, D., Etile, A., Ferdi, C., Feuerbach, R. J., Finn, J. M., Flay, D., Franklin, G. B., Friend, M., Frullani, S., Fuchey, E., Fuchs, S. A., Fuoti, K., Garibaldi, F., Gasser, E., Gilman, R., Giusa, A., Glamazdin, A., Glesener, L. E., Gomez, J., Gorchtein, M., Grames, J., Grimm, K., Gu, C., Hansen, O., Hansknecht, J., Hen, O., Higinbotham, D. W., Holmes, R. S., Holmstrom, T., Horowitz, C. J., Hoskins, J., Huang, J., Humensky, T. B., Hyde, C. E., Ibrahim, H., Itard, F., Jen, C. M., Jensen, E., Jiang, X., Jin, G., Johnston, S., Katich, J., Kaufman, L. J., Kelleher, A., Kliakhandler, K., King, P. M., Kolarkar, A., Kowalski, S., Kuchina, E., Kumar, K. S., Lagamba, L., Lambert, D., LaViolette, P., Leacock, J., Leckey IV, J., Lee, J. H., LeRose, J. J., Lhuillier, D., Lindgren, R., Liyanage, N., Lubinsky, N., Mammei, J., Mammoliti, F., Margaziotis, D. J., Markowitz, P., Mazouz, M., McCormick, K., McCreary, A., McNulty, D., Meekins, D. G., Mercado, L., Meziani, Z. E., Michaels, R. W., Mihovilovic, M., Moffit, B., Monaghan, P., Muangma, N., Munoz-Camacho, C., Nanda, S., Nelyubin, V., Neyret, D., Nuruzzaman, Oh, Y., Otis, K., Palmer, A., Parno, D., Paschke, K. D., Phillips, S. K., Poelker, M., Pomatsalyuk, R., Posik, M., Potokar, M., Prok, K., Puckett, A. J. R., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Reitz, B., Riordan, S., Roche, J., Rogan, P., Ron, G., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Singh, J., Sirca, S., Slifer, K., Snyder, R., Solvignon, P., Souder, P. A., Sperduto, M. L., Subedi, R., Stutzman, M. L., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Troth, W., Urciuoli, G. M., Ulmer, P., Vacheret, A., Voutier, E., Waidyawansa, B., Wang, D., Wang, K., Wexler, J., Whitbeck, A., Wilson, R., Wojtsekhowski, B., Yan, X., Yao, H., Ye, Y., Ye, Z., Yim, V., Zana, L., Zhan, X., Zhang, J., Zhang, Y., Zheng, X., Ziskin, V., and Zhu, P.

Subjects
Nuclear Experiment
Abstract

We have measured the beam-normal single-spin asymmetry $A_n$ in the elastic scattering of 1-3 GeV transversely polarized electrons from $^1$H and for the first time from $^4$He, $^{12}$C, and $^{208}$Pb. For $^1$H, $^4$He and $^{12}$C, the measurements are in agreement with calculations that relate $A_n$ to the imaginary part of the two-photon exchange amplitude including inelastic intermediate states. Surprisingly, the $^{208}$Pb result is significantly smaller than the corresponding prediction using the same formalism. These results suggest that a systematic set of new $A_n$ measurements might emerge as a new and sensitive probe of the structure of heavy nuclei., Comment: 5 pages, 3 figures, accepted by PRL. v3: fixed one author name and affiliation, otherwise no change

Published
2012
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8. Measurement of the Neutron Radius of 208Pb Through Parity-Violation in Electron Scattering

Author

Abrahamyan, S., Ahmed, Z., Albataineh, H., Aniol, K., Armstrong, D. S., Armstrong, W., Averett, T., Babineau, B., Barbieri, A., Bellini, V., Beminiwattha, R., Benesch, J., Benmokhtar, F., Bielarski, T., Boeglin, W., Camsonne, A., Canan, M., Carter, P., Cates, G. D., Chen, C., Chen, J. -P., Hen, O., Cusanno, F., Dalton, M. M., De Leo, R., de Jager, K., Deconinck, W., Decowski, P., Deng, X., Deur, A., Dutta, D., Etile, A., Flay, D., Franklin, G. B., Friend, M., Frullani, S., Fuchey, E., Garibaldi, F., Gasser, E., Gilman, R., Giusa, A., Glamazdin, A., Gomez, J., Grames, J., Gu, C., Hansen, O., Hansknecht, J., Higinbotham, D. W., Holmes, R. S., Holmstrom, T., Horowitz, C. J., Hoskins, J., Huang, J., Hyde, C. E., Itard, F., Jen, C. -M., Jensen, E., Jin, G., Johnston, S., Kelleher, A., Kliakhandler, K., King, P. M., Kowalski, S., Kumar, K. S., Leacock, J., Leckey IV, J., Lee, J. H., LeRose, J. J., Lindgren, R., Liyanage, N., Lubinsky, N., Mammei, J., Mammoliti, F., Margaziotis, D. J., Markowitz, P., McCreary, A., McNulty, D., Mercado, L., Meziani, Z. -E., Michaels, R. W., Mihovilovic, M., Muangma, N., Muñoz-Camacho, C., Nanda, S., Nelyubin, V., Nuruzzaman, N., Oh, Y., Palmer, A., Parno, D., Paschke, K. D., Phillips, S. K., Poelker, B., Pomatsalyuk, R., Posik, M., Puckett, A. J. R., Quinn, B., Rakhman, A., Reimer, P. E., Riordan, S., Rogan, P., Ron, G., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Sirca, S., Slifer, K., Solvignon, P., Souder, P. A., Sperduto, M. L., Subedi, R., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Troth, W., Urciuoli, G. M., Waidyawansa, B., Wang, D., Wexler, J., Wilson, R., Wojtsekhowski, B., Yan, X., Yao, H., Ye, Y., Ye, Z., Yim, V., Zana, L., Zhan, X., Zhang, J., Zhang, Y., Zheng, X., and Zhu, P.

Subjects
Nuclear Experiment
Abstract

We report the first measurement of the parity-violating asymmetry A_PV in the elastic scattering of polarized electrons from 208Pb. A_PV is sensitive to the radius of the neutron distribution (Rn). The result A_PV = 0.656 \pm 0.060 (stat) \pm 0.014 (syst) ppm corresponds to a difference between the radii of the neutron and proton distributions Rn - Rp = 0.33 +0.16 -0.18 fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus., Comment: 6 pages, 1 figure

Published
2012
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9. Measurement of the parity-violating asymmetry in inclusive electroproduction of $\pi^-$ near the $\Delta^0$ resonance

Author

G0 Collaboration, Androić, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. -C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. -S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., and Wood, S. A.

Subjects
Nuclear Experiment
Abstract

The parity-violating (PV) asymmetry of inclusive $\pi^-$ production in electron scattering from a liquid deuterium target was measured at backward angles. The measurement was conducted as a part of the G0 experiment, at a beam energy of 360 MeV. The physics process dominating pion production for these kinematics is quasi-free photoproduction off the neutron via the $\Delta^0$ resonance. In the context of heavy-baryon chiral perturbation theory (HB$\chi$PT), this asymmetry is related to a low energy constant $d_\Delta^-$ that characterizes the parity-violating $\gamma$N$\Delta$ coupling. Zhu et al. calculated $d_\Delta^-$ in a model benchmarked by the large asymmetries seen in hyperon weak radiative decays, and predicted potentially large asymmetries for this process, ranging from $A_\gamma^-=-5.2$ to $+5.2$ ppm. The measurement performed in this work leads to $A_\gamma^-=-0.36\pm 1.06\pm 0.37\pm 0.03$ ppm (where sources of statistical, systematic and theoretical uncertainties are included), which would disfavor enchancements considered by Zhu et al. proportional to $V_{ud}/V_{us}$. The measurement is part of a program of inelastic scattering measurements that were conducted by the G0 experiment, seeking to determine the $N-\Delta$ axial transition form-factors using PV electron scattering., Comment: 5 pages, 3 figures

Published
2011
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10. Transverse Beam Spin Asymmetries at Backward Angles in Elastic Electron-Proton and Quasi-elastic Electron-Deuteron Scattering

Author

The G0 Collaboration, Androić, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. -C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, 10 S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. -S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Pasquini, B., and Vanderhaeghen, M.

Subjects
Nuclear Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract

We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasi-elastic scattering on the deuteron, at backward angles (lab scattering angle of 108 degrees) for Q2 = 0.22 GeV^2/c^2 and 0.63 GeV^2/c^2 at beam energies of 362 MeV and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (piN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasi-static deuterium approximation, and is also in agreement with theory.

Published
2011
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11. The G0 Experiment: Apparatus for Parity-Violating Electron Scattering Measurements at Forward and Backward Angles

Author

G0 Collaboration, Androic, D., Armstrong, D. S., Arvieux, J., Asaturyan, R., Averett, T. D., Bailey, S. L., Batigne, G., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Biselli, A., Bosted, P., Breuer, H., Brindza, P., Capuano, C. L., Carlini, R. D., Carr, R., Chant, N., Chao, Y. -C., Clark, R., Coppens, A., Covrig, S. D., Cowley, A., Dale, D., Davis, C. A., Ellis, C., Falk, W. R., Fenker, H., Finn, J. M., Forest, T., Franklin, G., Frascaria, R., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Griffioen, K. A., Grimm, K., Guillard, G., Guillon, B., Guler, H., Gustafsson, K., Hannelius, L., Hansknecht, J., Hasty, R. D., Allen, A. M. Hawthorne, Horn, T., Ito, T. M., Johnston, K., Jones, M., Kammel, P., Kazimi, R., King, P. M., Kolarkar, A., Korkmaz, E., Korsch, W., Kox, S., Kuhn, J., Lachniet, J., Laszewski, R., Lee, L., Lenoble, J., Liatard, E., Liu, J., Lung, A., MacLachlan, G. A., Mammei, J., Marchand, D., Martin, J. W., Mack, D. J., McFarlane, K. W., McKee, D. W., McKeown, R. D., Merchez, F., Mihovilovic, M., Micherdzinska, A., Mkrtchyan, H., Moffit, B., Morlet, M., Muether, M., Musson, J., Nakahara, K., Neveling, R., Niccolai, S., Nilsson, D., Ong, S., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Porcelli, T. A., Quemener, G., Quinn, B. P., Ramsay, W. D., Rauf, A. W., Real, J. -S., Ries, T., Roos, J. Roche P., Rutledge, G. A., Schaub, J., Secrest, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stepanyan, S., Stutzman, M., Suleiman, R., Tadevosyan, V., Tieulent, R., van de Wiele, J., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W. F., Wells, S. P., Warren, G., Williamson, S. E., Woo, R. J., Wood, S. A., Yan, C., Yun, J., and Zeps, V.

Subjects
Nuclear Experiment, Physics - Instrumentation and Detectors
Abstract

In the G0 experiment, performed at Jefferson Lab, the parity-violating elastic scattering of electrons from protons and quasi-elastic scattering from deuterons is measured in order to determine the neutral weak currents of the nucleon. Asymmetries as small as 1 part per million in the scattering of a polarized electron beam are determined using a dedicated apparatus. It consists of specialized beam-monitoring and control systems, a cryogenic hydrogen (or deuterium) target, and a superconducting, toroidal magnetic spectrometer equipped with plastic scintillation and aerogel Cerenkov detectors, as well as fast readout electronics for the measurement of individual events. The overall design and performance of this experimental system is discussed., Comment: Submitted to Nuclear Instruments and Methods

Published
2011
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12. The Qweak experimental apparatus

Author

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., and Zielinski, R.B.

Published
2015
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13. High Precision 5 MeV Mott Polarimeter

Author

Grames, J. M., primary, Sinclair, C. K., additional, Poelker, M., additional, Roca-Maza, X., additional, Stutzman, M. L., additional, Suleiman, R., additional, Mamun, Md. A., additional, Mchugh, M. J., additional, Hansknecht, J., additional, Moffit, B., additional, and Gay, T. J., additional

Published
2022
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17. Thermal emittance and lifetime of alkali-antimonide photocathodes grown on GaAs and molybdenum substrates evaluated in a −300 kV dc photogun

Author

Wang, Y., primary, Mamun, M. A., additional, Adderley, P., additional, Bullard, B., additional, Grames, J., additional, Hansknecht, J., additional, Hernandez-Garcia, C., additional, Kazimi, R., additional, Krafft, G. A., additional, Palacios-Serrano, G., additional, Poelker, M., additional, Stutzman, M. L., additional, Suleiman, R., additional, Tiefenback, M., additional, Wijethunga, S., additional, Yoskowitz, J., additional, and Zhang, S., additional

Published
2020
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18. High precision 5 MeV Mott polarimeter

Author

Grames, J. M., primary, Sinclair, C. K., additional, Poelker, M., additional, Roca-Maza, X., additional, Stutzman, M. L., additional, Suleiman, R., additional, Mamun, Md. A., additional, McHugh, M., additional, Moser, D., additional, Hansknecht, J., additional, Moffit, B., additional, and Gay, T. J., additional

Published
2020
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19. Evaluation of Niobium as Candidate Electrode Material for DC High Voltage Photoelectron Guns

Author

BastaniNejad, M, Mohamed, Abdullah, Elmustafa, A. A, Adderley, P, Clark, J, Covert, S, Hansknecht, J, Hernandez-Garcia, C, Poelker, M, Mammei, R, Surles-Law, K, and Williams, P

Subjects
Electronics And Electrical Engineering
Abstract

The field emission characteristics of niobium electrodes were compared to those of stainless steel electrodes using a DC high voltage field emission test apparatus. A total of eight electrodes were evaluated: two 304 stainless steel electrodes polished to mirror-like finish with diamond grit and six niobium electrodes (two single-crystal, two large-grain, and two fine-grain) that were chemically polished using a buffered-chemical acid solution. Upon the first application of high voltage, the best large-grain and single-crystal niobium electrodes performed better than the best stainless steel electrodes, exhibiting less field emission at comparable voltage and field strength. In all cases, field emission from electrodes (stainless steel and/or niobium) could be significantly reduced and sometimes completely eliminated, by introducing krypton gas into the vacuum chamber while the electrode was biased at high voltage. Of all the electrodes tested, a large-grain niobium electrode performed the best, exhibiting no measurable field emission (< 10 pA) at 225 kV with 20 mm cathode/anode gap, corresponding to a field strength of 18:7 MV/m.

Published
2012
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20. Compact −300 kV dc inverted insulator photogun with biased anode and alkali-antimonide photocathode

Author

Hernandez-Garcia, C., primary, Adderley, P., additional, Bullard, B., additional, Benesch, J., additional, Grames, J., additional, Gubeli, J., additional, Hannon, F., additional, Hansknecht, J., additional, Jordan, J., additional, Kazimi, R., additional, Krafft, G. A., additional, Mamun, M. A., additional, Poelker, M., additional, Stutzman, M. L., additional, Suleiman, R., additional, Tiefenback, M., additional, Wang, Y., additional, Zhang, S., additional, Baumgart, H., additional, Palacios-Serrano, G., additional, Wijethunga, S., additional, Yoskowitz, J., additional, Valerio Lizarraga, C. A., additional, Montoya Soto, R., additional, and Canales Ramos, A., additional

Published
2019
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21. Magnetized electron beam for the JLEIC re-circulator cooler ring

Author

Poelker, Matt, primary, Adderley, P., additional, Benesch, J., additional, Bullard, B., additional, Grames, J., additional, Hannon, F., additional, Hansknecht, J., additional, Hernandez-Garcia, C., additional, Kazimi, R., additional, Krafft,, G., additional, Mamun, M., additional, Suleiman, R., additional, Tiefenback, M., additional, Wang, Y., additional, Wijiethunga, S., additional, Yoskovitz, J., additional, and Zhang, S., additional

Published
2018
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24. Constraints on the nucleon strange form factors at Q2∼0.1 GeV2

Author

Aniol, K.A., Armstrong, D.S., Averett, T., Benaoum, H., Bertin, P.Y., Burtin, E., Cahoon, J., Cates, G.D., Chang, C.C., Chao, Y.-C., Chen, J.P., Choi, Seonho, Chudakov, E., Craver, B., Cusanno, F., Decowski, P., Deepa, D., Ferdi, C., Feuerbach, R.J., Finn, J.M., Frullani, S., Fuoti, K., Garibaldi, F., Gilman, R., Glamazdin, A., Gorbenko, V., Grames, J.M., Hansknecht, J., Higinbotham, D.W., Holmes, R., Holmstrom, T., Humensky, T.B., Ibrahim, H., de Jager, C.W., Jiang, X., Kaufman, L.J., Kelleher, A., Kolarkar, A., Kowalski, S., Kumar, K.S., Lambert, D., LaViolette, P., LeRose, J., Lhuillier, D., Liyanage, N., Margaziotis, D.J., Mazouz, M., McCormick, K., Meekins, D.G., Meziani, Z.-E., Michaels, R., Moffit, B., Monaghan, P., Munoz-Camacho, C., Nanda, S., Nelyubin, V., Neyret, D., Paschke, K.D., Poelker, M., Pomatsalyuk, R., Qiang, Y., Reitz, B., Roche, J., Saha, A., Singh, J., Snyder, R., Souder, P.A., Stutzman, M., Subedi, R., Suleiman, R., Sulkosky, V., Tobias, W.A., Urciuoli, G.M., Vacheret, A., Voutier, E., Wang, K., Wilson, R., Wojtsekhowski, B., and Zheng, X.

Subjects
Nuclear and High Energy Physics
Published
2006
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25. Measurement of the parity-violating asymmetry in inclusive electroproduction of $\pi^-$ near the $\Delta^0$ resonance

Author

G0 Collaboration, Androić, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. -C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. -S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), and G0

Subjects
High Energy Physics::Experiment, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract

The parity-violating (PV) asymmetry of inclusive $\pi^-$ production in electron scattering from a liquid deuterium target was measured at backward angles. The measurement was conducted as a part of the G0 experiment, at a beam energy of 360 MeV. The physics process dominating pion production for these kinematics is quasi-free photoproduction off the neutron via the $\Delta^0$ resonance. In the context of heavy-baryon chiral perturbation theory (HB$\chi$PT), this asymmetry is related to a low energy constant $d_\Delta^-$ that characterizes the parity-violating $\gamma$N$\Delta$ coupling. Zhu et al. calculated $d_\Delta^-$ in a model benchmarked by the large asymmetries seen in hyperon weak radiative decays, and predicted potentially large asymmetries for this process, ranging from $A_\gamma^-=-5.2$ to $+5.2$ ppm. The measurement performed in this work leads to $A_\gamma^-=-0.36\pm 1.06\pm 0.37\pm 0.03$ ppm (where sources of statistical, systematic and theoretical uncertainties are included), which would disfavor enchancements considered by Zhu et al. proportional to $V_{ud}/V_{us}$. The measurement is part of a program of inelastic scattering measurements that were conducted by the G0 experiment, seeking to determine the $N-\Delta$ axial transition form-factors using PV electron scattering., Comment: 5 pages, 3 figures

Published
2012
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26. Measurement of the Neutron Radius of Pb-208 through Parity Violation in Electron Scattering

Author

Abrahamyan, S, Ahmed, Z, Albataineh, H, Aniol, K, Armstrong, Ds, Armstrong, W, Averett, T, Babineau, B, Barbieri, A, Bellini, Vincenzo, Beminiwattha, R, Benesch, J, Benmokhtar, F, Bielarski, T, Boeglin, W, Camsonne, A, Canan, M, Carter, P, Cates, Gd, Chen, C, Chen, Jp, Hen, O, Cusanno, F, Dalton, Mm, De, Le, R, de Jager, K, Deconinck, W, Decowski, P, Deng, X, Deur, A, Dutta, D, Etile, A, Flay, D, Franklin, Gb, Friend, M, Frullani, S, Fuchey, E, Garibaldi, F, Gasser, E, Gilman, R, Giusa, A, Glamazdin, A, Gomez, J, Grames, J, Gu, C, Hansen, O, Hansknecht, J, Higinbotham, Dw, Holmes, Rs, Holmstrom, T, Horowitz, Cj, Hoskins, J, Huang, J, Hyde, Ce, Itard, F, Jen, Cm, Jensen, E, Jin, G, Johnston, S, Kelleher, A, Kliakhandler, K, King, Pm, Kowalski, S, Kumar, Ks, Leacock, J, Leckey, J, Lee, Jh, Lerose, Jj, Lindgren, R, Liyanage, N, Lubinsky, N, Mammei, J, Mammoliti, Francesco, Margaziotis, Dj, Markowitz, P, Mccreary, A, Mcnulty, D, Mercado, L, Meziani, Ze, Michaels, Rw, Mihovilovic, M, Muangma, N, Munoz Camacho, C, Nanda, S, Nelyubin, V, Nuruzzaman, N, Oh, Y, Palmer, A, Parno, D, Paschke, Kd, Phillips, Sk, Poelker, B, Pomatsalyuk, R, Posik, M, Puckett, Ajr, Quinn, B, Rakhman, A, Reimer, Pe, Riordan, S, Rogan, P, Ron, G, Russo, Giuseppe, Saenboonruang, K, Saha, A, Sawatzky, B, Shahinyan, A, Silwal, R, Sirca, S, Slifer, K, Solvignon, P, Souder, Pa, Sperduto, Ml, Subedi, R, Suleiman, R, Sulkosky, V, Sutera, CONCETTA MARIA, Tobias, Wa, Troth, W, Urciuoli, Gm, Waidyawansa, B, Wang, D, Wexler, J, Wilson, R, Wojtsekhowski, B, Yan, X, Yao, H, Ye, Y, Ye, Z, Yim, V, Zana, L, Zhan, X, Zhang, J, Zhang, Y, Zheng, X, and PREX Collaboration, Zhu P.

Subjects
ELECTRON-SCATTERING, NUCLEI, DENSITIES
Published
2012

28. Precision Measurements of the Nucleon Strange Form Factors at Q^2 ~0.1 GeV^2

Author

Acha, A., Aniol, K.A., Armstrong, D.S., Arrington, J., Averett, T., Bailey, S., Barber, J., Beck, A., Benaoum, H., Benesch, J., Bertin, P.Y., Bosted, P., Butaru, F., Burtin, E., Cates, G., Chao, Y.-C., Chen, J.-P., Chudakov, E., Cisbani, E., Craver, B., Cusanno, F., de Leo, R., Decowski, P., Deur, A., Feuerbach, R., Finn, J., Frullani, S., Fuchs, S., Fuoti, K., Gilman, R., Glesener, L., Grimm, K., Grames, J., Hansen, J.-O., Hansknecht, J., Higinbotham, D., Holmes, R., Holmstrom, T., Ibrahim, H., de Jager, C., Jiang, X., Katich, J., Kaufman, L., Kelleher, A., King, P., Kolarkar, A., Kowalski, S., Kuchina, E., Kumar, K., Lagamba, L., Laviolette, P., Lerose, J., Lindgren, R., Lhuillier, D., Liyanage, N., Margaziotis, D., Markowitz, P., Meekins, D., Meziani, Z.-E., Michaels, R., Moffit, B., Nanda, S., Nelyubin, V., Otis, K., Paschke, K., Philips, S., Poelker, B., Pomatsalyuk, R., Potokar, M., Prok, Y., Puckett, A., Qian, Y., Qiang, Y., Reitz, B., Roche, J., Saha, A., Sawatzky, B., Singh, J., Slifer, K., Sirca, S., Snyder, R., Solvignon, P., Souder, P., Stutzman, M., Subedi, R., Suleiman, R., Sulkosky, V., Ulmer, P., Urciuoli, G., Wang, K., Wilson, R., Wojtsekhowski, B., Yao, H., Ye, Y., Zhan, X., Zheng, X., Zhou, S., Ziskin, V., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and HAPPEX

Subjects
FOS: Physical sciences, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment, 25.30.Bf, 13.60.Fz, 11.30.Er, 13.40.Gp, 14.20.Dh
Abstract

We report new measurements of the parity-violating asymmetry A_PV in elastic scattering of 3 GeV electrons off hydrogen and 4He targets with ~6.0 degrees. The 4He result is A_PV = (+6.40 +/- 0.23 (stat) +/- 0.12 (syst)) x10^-6. The hydrogen result is A_PV = (-1.58 +/- 0.12 (stat) +/- 0.04 (syst)) x10^-6. These results significantly improve constraints on the electric and magnetic strange form factors G_E^s and G_M^s. We extract G_E^s = 0.002 +/- 0.014 +/- 0.007 at = 0.077 GeV^2, and G_E^s + 0.09 G_M^s = 0.007 +/- 0.011 +/- 0.006 at = 0.109 GeV^2, providing new limits on the role of strange quarks in the nucleon charge and magnetization distributions., Comment: 4.5 pages, 2 figures. Replacement, modifying a few sentences, captions, and labels for clarity

Published
2007
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29. Constraints on the nucleon strange form factors at Q(2)similar to 0.1 GeV2

Author

Aniol, KA, Armstrong, DS, Averett, T, Benaoum, H, Bertin, PY, Burtin, E, Cahoon, J, Gates, GD, Chang, CC, Chao, YC, Chen, JP, Choi, SH, Chudakov, E, Craver, B, Cusanno, F, Decowski, P, Deepa, D, Ferdi, C, Feuerbach, RJ, Finn, JM, Frullani, S, Fuoti, K, Garibaldi, F, Gilman, R, Glamazdin, A, Gorbenko, V, Grames, JM, Hansknecht, J, Higinbotham, DW, Holmes, R, Holmstrom, T, Humensky, TB, Ibrahim, H, de Jager, CW, Jiang, X, Kaufman, LJ, Kelleher, A, Kolarkar, A, Kowalski, S, Kumar, KS, Lambert, D, LaViolette, P, LeRose, J, Lhuillier, D, Liyanage, N, Margaziotis, DJ, Mazouz, M, McCormick, K, Meekins, DG, Meziani, ZE, Michaels, R, Moffit, B, Monaghan, P, Munoz-Camacho, C, Nanda, S, Nelyubin, V, Neyret, D, Paschke, KD, Poelker, M, Pomatsalyuk, R, Qiang, Y, Reitz, B, Roche, J, Saha, A, Singh, J, Snyder, R, Souder, PA, Stutzman, M, Subedi, R, Suleiman, R, Sulkosky, V, Tobias, WA, Urciuoli, GM, Vacheret, A, Voutier, E, Wang, K, Wilson, R, Wojtsekhowski, B, and Zheng, X

Published
2006

30. Parity-violating electron scattering from 4He and the strange electric form factor of the nucleon

Author

Aniol, KA, Armstrong, DS, Averett, T, Benaoum, H, Bertin, PY, Burtin, E, Cahoon, J, Cates, GD, Chang, CC, Chao, YC, Chen, JP, Choi, S, Chudakov, E, Craver, B, Cusanno, F, Decowski, P, Deepa, D, Ferdi, C, Feuerbach, RJ, Finn, JM, Frullani, S, Fuoti, K, Garibaldi, F, Gilman, R, Glamazdin, A, Gorbenko, V, Grames, JM, Hansknecht, J, Higinbotham, DW, Holmes, R, Holmstrom, T, Humensky, TB, Ibrahim, H, de Jager, CW, Jiang, X, Kaufman, LJ, Kelleher, A, Kolarkar, A, Kowalski, S, Kumar, KS, Lambert, D, LaViolette, P, LeRose, J, Lhuillier, D, Liyanage, N, Margaziotis, DJ, Mazouz, M, McCormick, K, Meekins, DG, Meziani, ZE, Michaels, R, Moffit, B, Monaghan, P, Munoz-Camacho, C, Nanda, S, Nelyubin, V, Neyret, D, Paschke, KD, Poelker, M, Pomatsalyuk, R, Qiang, Y, Reitz, B, Roche, J, Saha, A, Singh, J, Snyder, R, Souder, PA, Subedi, R, Suleiman, R, Sulkosky, V, Tobias, WA, Urciuoli, GM, Vacheret, A, Voutier, E, Wang, K, Wilson, R, Wojtsekhowski, B, and Zheng, X

Subjects
High Energy Physics::Experiment, Nuclear Experiment
Abstract

We have measured the parity-violating electroweak asymmetry in the elastic scattering of polarized electrons from 4He at an average scattering angle = 5.7 degrees and a four-momentum transfer Q2 = 0.091 GeV2 . From these data, for the first time, the strange electric form factor of the nucleon G(E)s can be isolated. The measured asymmetry of A(PV) = (6.72 +/- 0.84(stat) +/- 0.21(syst) x 10(-6) yields a value of G(E)s = -0.038 +/- 0.042(stat) +/- 0.010(syst), consistent with zero.

Published
2005

31. Constraints on the Nucleon Strange Form Factors at Q^2 ~ 0.1 GeV^2

Author

Aniol, K., Armstrong, D., Averett, T., Benaoum, H., Bertin, P.Y., Burtin, E., Cahoon, J., Cates, G., Chang, C., Chao, Y.-C., Chen, Jie, Choi, S., Chudakov, E., Craver, B., Cusanno, F., Decowski, P., Deepa, D., Ferdi, C., Feuerbach, R., Finn, J., Frullani, S., Fuoti, K., Garibaldi, F., Gilman, R., Glamazdin, O., Gorbenko, V., Grames, J., Hansknecht, J., Higinbotham, D., Holmes, R., Holmstrom, T., Humensky, T., Ibrahim, H., De Jager, C., Jiang, X., Kaufman, L., Kelleher, A., Kolarkar, A., Kowalski, S., Kumar, K., Lambert, D., Laviolette, P., LeRose, J., Lhuillier, D., Liyanage, N., Margaziotis, D., Mazouz, M., McCormick, K., Meekins, D., Meziani, Z.-E., Michaels, R., Moffit, B., Monaghan, P., Munoz-Camacho, C., Nanda, S., Nelyubin, V., Neyret, D., Paschke, K.D., Poelker, B., Pomatsalyuk, R., Qiang, Y., Reitz, B., Roche, J., Saha, A., Singh, J., Snyder, R., Souder, P.A., Stutzman, M., Subedi, R., Suleiman, R., Sulkosky, V., Tobias, W., Urciuoli, G., Vacheret, A., Voutier, E., Wang, K., Wilson, R., Wojtsekhowski, B., Zheng, X., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), HAPPEX, and Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)

Subjects
FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

We report the most precise measurement to date of a parity-violating asymmetry in elastic electron-proton scattering. The measurement was carried out with a beam energy of 3.03 GeV and a scattering angle =6 degrees, with the result A_PV = -1.14 +/- 0.24 (stat) +/- 0.06 (syst) parts per million. From this we extract, at Q^2 = 0.099 GeV^2, the strange form factor combination G_E^s + 0.080 G_M^s = 0.030 +/- 0.025 (stat) +/- 0.006 (syst) +/- 0.012 (FF) where the first two errors are experimental and the last error is due to the uncertainty in the neutron electromagnetic form factor. This result significantly improves current knowledge of G_E^s and G_M^s at Q^2 ~0.1 GeV^2. A consistent picture emerges when several measurements at about the same Q^2 value are combined: G_E^s is consistent with zero while G_M^s prefers positive values though G_E^s=G_M^s=0 is compatible with the data at 95% C.L., Comment: minor wording changes for clarity, updated references, dropped one figure to improve focus

Published
2005
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33. Measurement of the Parity-Violating Asymmetry in Inclusive Electroproduction of pi(-) near the Delta(0) Resonance

Author

Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., and Wood, S. A.

Abstract

The parity-violating (PV) asymmetry of inclusive pi(-) production in electron scattering from a liquid deuterium target was measured at backward angles. The measurement was conducted as a part of the G0 experiment, at a beam energy of 360 MeV. The physics process dominating pion production for these kinematics is quasifree photoproduction off the neutron via the Delta(0) resonance. In the context of heavy-baryon chiral perturbation theory, this asymmetry is related to a low-energy constant d(Delta)(-) that characterizes the parity-violating gamma N Delta coupling. Zhu et al. calculated d(Delta)(-) in a model benchmarked by the large asymmetries seen in hyperon weak radiative decays, and predicted potentially large asymmetries for this process, ranging from A(gamma)(-) = -5.2 to + 5.2 ppm. The measurement performed in this work leads to A(gamma)(-) = -0.36 +/- 1.06 +/- 0.37 +/- 0.03 ppm (where sources of statistical, systematic and theoretical uncertainties are included), which would disfavor enchancements considered by Zhu et al. proportional to V-ud/V-us. The measurement is part of a program of inelastic scattering measurements that were conducted by the G0 experiment, seeking to determine the N - Delta axial transition form factors using PV electron scattering.

Published
2012
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34. Measurement of the Parity-Violating Asymmetry in Inclusive Electroproduction of pi(-) near the Delta(0) Resonance

Author

Physics, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Physics, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., and Wood, S. A.

Abstract

The parity-violating (PV) asymmetry of inclusive pi(-) production in electron scattering from a liquid deuterium target was measured at backward angles. The measurement was conducted as a part of the G0 experiment, at a beam energy of 360 MeV. The physics process dominating pion production for these kinematics is quasifree photoproduction off the neutron via the Delta(0) resonance. In the context of heavy-baryon chiral perturbation theory, this asymmetry is related to a low-energy constant d(Delta)(-) that characterizes the parity-violating gamma N Delta coupling. Zhu et al. calculated d(Delta)(-) in a model benchmarked by the large asymmetries seen in hyperon weak radiative decays, and predicted potentially large asymmetries for this process, ranging from A(gamma)(-) = -5.2 to + 5.2 ppm. The measurement performed in this work leads to A(gamma)(-) = -0.36 +/- 1.06 +/- 0.37 +/- 0.03 ppm (where sources of statistical, systematic and theoretical uncertainties are included), which would disfavor enchancements considered by Zhu et al. proportional to V-ud/V-us. The measurement is part of a program of inelastic scattering measurements that were conducted by the G0 experiment, seeking to determine the N - Delta axial transition form factors using PV electron scattering.

Published
2012

35. Transverse Beam Spin Asymmetries at Backward Angles in Elastic Electron-Proton and Quasielastic Electron-Deuteron Scattering

Author

Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Pasquini, B., Vanderhaeghen, M., G0 Collaboration, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Pasquini, B., Vanderhaeghen, M., and G0 Collaboration

Abstract

We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasielastic scattering on the deuteron, at backward angles (lab scattering angle of 108 degrees) for Q(2) = 0.22 GeV2/c(2) and 0.63 GeV2/c(2) at beam energies of 362 and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single-photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (pi N) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasistatic deuterium approximation, and is also in agreement with theory.

Published
2011
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36. Transverse Beam Spin Asymmetries at Backward Angles in Elastic Electron-Proton and Quasielastic Electron-Deuteron Scattering

Author

Physics, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Pasquini, B., Vanderhaeghen, M., G0 Collaboration, Physics, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Pasquini, B., Vanderhaeghen, M., and G0 Collaboration

Abstract

We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasielastic scattering on the deuteron, at backward angles (lab scattering angle of 108 degrees) for Q(2) = 0.22 GeV2/c(2) and 0.63 GeV2/c(2) at beam energies of 362 and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single-photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (pi N) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasistatic deuterium approximation, and is also in agreement with theory.

Published
2011

37. Measurement of Electron Beam Polarization from Unstrained Bulk GaAs via Two Photon Photoemission

Author

McCarter, J L, Gay, Timothy J., Hansknecht, J, Poelker, M, Stutzman, M L, McCarter, J L, Gay, Timothy J., Hansknecht, J, Poelker, M, and Stutzman, M L

Abstract

This paper describes measurements of the beam polarization and quantum efficiency for photo-emission using two-photon excitation from unstrained bulk GaAs illuminated with pulsed, high intensity 1560nm laser light. Quantum efficiency is linearly proportional to 1560nm peak laser intensity, which was varied in three independent ways, indicating that the emitted electrons are promoted from the valence to the conduction band via two-photon absorption. Beam polarization was measured using a microMott polarimeter, with a value of 16.8(4)% polarization at 1560nm, which is roughly half the measured value of 33.4(8)% using 778 nm light.

Published
2011

38. Strange Quark Contributions to Parity-Violating Asymmetries in the Backward Angle G0 Electron Scattering Experiment

Author

Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. I. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Mihovilovic, M., Micherdzinska, A., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., G0 Collaboration, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. I. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Mihovilovic, M., Micherdzinska, A., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., and G0 Collaboration

Abstract

We have measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at Q(2) = 0.22 and 0.63 GeV(2). They are sensitive to strange quark contributions to currents in the nucleon and the nucleon axial-vector current. The results indicate strange quark contributions of less than or similar to 10% of the charge and magnetic nucleon form factors at these four-momentum transfers. We also present the first measurement of anapole moment effects in the axial-vector cur-rent at these four-momentum transfers.

Published
2010
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39. Strange Quark Contributions to Parity-Violating Asymmetries in the Backward Angle G0 Electron Scattering Experiment

Author

Physics, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. I. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Mihovilovic, M., Micherdzinska, A., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., G0 Collaboration, Physics, Androic, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. I. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Mihovilovic, M., Micherdzinska, A., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., and G0 Collaboration

Abstract

We have measured parity-violating asymmetries in elastic electron-proton and quasielastic electron-deuteron scattering at Q(2) = 0.22 and 0.63 GeV(2). They are sensitive to strange quark contributions to currents in the nucleon and the nucleon axial-vector current. The results indicate strange quark contributions of less than or similar to 10% of the charge and magnetic nucleon form factors at these four-momentum transfers. We also present the first measurement of anapole moment effects in the axial-vector cur-rent at these four-momentum transfers.

Published
2010

40. Erratum: Evaluation of niobium as candidate electrode material for dc high voltage photoelectron guns [Phys. Rev. ST Accel. Beams 15, 083502 (2012)]

Author

BastaniNejad, M., primary, Mohamed, Md. Abdullah, additional, Elmustafa, A. A., additional, Adderley, P., additional, Clark, J., additional, Covert, S., additional, Hansknecht, J., additional, Hernandez-Garcia, C., additional, Poelker, M., additional, Mammei, R., additional, Surles-Law, K., additional, and Williams, P., additional

Published
2014
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41. Charge lifetime measurements at high average current using aK2CsSbphotocathode inside a dc high voltage photogun

Author

Mammei, R. R., primary, Suleiman, R., additional, Feingold, J., additional, Adderley, P. A., additional, Clark, J., additional, Covert, S., additional, Grames, J., additional, Hansknecht, J., additional, Machie, D., additional, Poelker, M., additional, Rao, T., additional, Smedley, J., additional, Walsh, J., additional, McCarter, J. L., additional, and Ruiz-Osés, M., additional

Published
2013
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42. Strange Quark Contributions to Parity-Violating Asymmetries in the Backward Angle G0 Electron Scattering Experiment

Author

Androic, D., Androic, D., Armstrong, D.S., Arvieux, J., Bailey, S.L., Beck, D.H., Beise, E.J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C.L., Chao, Y.C., Coppens, A., Davis, C.A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M.T.W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M., King, P.M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J.W., McKeown, R.D., Mihovilovic, M., Micherdzinska, A., Mkrtchyan, H., Muether, M., Page, S.A., Papavassiliou, V., Pate, S.F., Phillips, S.K., Pillot, P., Pitt, M.L., Poelker, M., Quinn, B., Ramsay, W.D., Real, J.S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G.R., Spayde, D.T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, T.H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S.P., Williamson, S.E., Wood, S.A., G0 Collaboration, Androic, D., Androic, D., Armstrong, D.S., Arvieux, J., Bailey, S.L., Beck, D.H., Beise, E.J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C.L., Chao, Y.C., Coppens, A., Davis, C.A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M.T.W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M., King, P.M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J.W., McKeown, R.D., Mihovilovic, M., Micherdzinska, A., Mkrtchyan, H., Muether, M., Page, S.A., Papavassiliou, V., Pate, S.F., Phillips, S.K., Pillot, P., Pitt, M.L., Poelker, M., Quinn, B., Ramsay, W.D., Real, J.S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G.R., Spayde, D.T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, T.H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S.P., Williamson, S.E., Wood, S.A., and G0 Collaboration

Abstract

We have measured parity-violating asymmetries in elastic electron-proton and quasi-elastic electron-deuteron scattering at Q2 = 0.22 and 0.63 GeV2. They are sensitive to strange quark contributions to currents in the nucleon, and to the nucleon axial current. The results indicate strange quark contributions of <∼ 10% of the charge and magnetic nucleon form factors at these four-momentum transfers. We also present the first measurement of anapole moment effects in the axial current at these four-momentum transfers

Published
2005

43. The G0 experiment: Apparatus for parity-violating electron scattering measurements at forward and backward angles

Author

Androić, D., primary, Armstrong, D.S., additional, Arvieux, J., additional, Asaturyan, R., additional, Averett, T.D., additional, Bailey, S.L., additional, Batigne, G., additional, Beck, D.H., additional, Beise, E.J., additional, Benesch, J., additional, Benmokhtar, F., additional, Bimbot, L., additional, Birchall, J., additional, Biselli, A., additional, Bosted, P., additional, Breuer, H., additional, Brindza, P., additional, Capuano, C.L., additional, Carlini, R.D., additional, Carr, R., additional, Chant, N., additional, Chao, Y.-C., additional, Clark, R., additional, Coppens, A., additional, Covrig, S.D., additional, Cowley, A., additional, Dale, D., additional, Davis, C.A., additional, Ellis, C., additional, Falk, W.R., additional, Fenker, H., additional, Finn, J.M., additional, Forest, T., additional, Franklin, G., additional, Frascaria, R., additional, Furget, C., additional, Gaskell, D., additional, Gericke, M.T.W., additional, Grames, J., additional, Griffioen, K.A., additional, Grimm, K., additional, Guillard, G., additional, Guillon, B., additional, Guler, H., additional, Gustafsson, K., additional, Hannelius, L., additional, Hansknecht, J., additional, Hasty, R.D., additional, Hawthorne Allen, A.M., additional, Horn, T., additional, Ito, T.M., additional, Johnston, K., additional, Jones, M., additional, Kammel, P., additional, Kazimi, R., additional, King, P.M., additional, Kolarkar, A., additional, Korkmaz, E., additional, Korsch, W., additional, Kox, S., additional, Kuhn, J., additional, Lachniet, J., additional, Laszewski, R., additional, Lee, L., additional, Lenoble, J., additional, Liatard, E., additional, Liu, J., additional, Lung, A., additional, MacLachlan, G.A., additional, Mammei, J., additional, Marchand, D., additional, Martin, J.W., additional, Mack, D.J., additional, McFarlane, K.W., additional, McKee, D.W., additional, McKeown, R.D., additional, Merchez, F., additional, Mihovilovic, M., additional, Micherdzinska, A., additional, Mkrtchyan, H., additional, Moffit, B., additional, Morlet, M., additional, Muether, M., additional, Musson, J., additional, Nakahara, K., additional, Neveling, R., additional, Niccolai, S., additional, Nilsson, D., additional, Ong, S., additional, Page, S.A., additional, Papavassiliou, V., additional, Pate, S.F., additional, Phillips, S.K., additional, Pillot, P., additional, Pitt, M.L., additional, Poelker, M., additional, Porcelli, T.A., additional, Quéméner, G., additional, Quinn, B.P., additional, Ramsay, W.D., additional, Rauf, A.W., additional, Real, J.-S., additional, Ries, T., additional, Roche, J., additional, Roos, P., additional, Rutledge, G.A., additional, Schaub, J., additional, Secrest, J., additional, Seva, T., additional, Simicevic, N., additional, Smith, G.R., additional, Spayde, D.T., additional, Stepanyan, S., additional, Stutzman, M., additional, Suleiman, R., additional, Tadevosyan, V., additional, Tieulent, R., additional, van de Wiele, J., additional, van Oers, W.T.H., additional, Versteegen, M., additional, Voutier, E., additional, Vulcan, W.F., additional, Wells, S.P., additional, Warren, G., additional, Williamson, S.E., additional, Woo, R.J., additional, Wood, S.A., additional, Yan, C., additional, Yun, J., additional, and Zeps, V., additional

Published
2011
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47. Strange Quark Contributions to Parity-Violating Asymmetries in the Backward Angle G0 Electron Scattering Experiment

Author

Androić, D., primary, Armstrong, D. S., additional, Arvieux, J., additional, Bailey, S. L., additional, Beck, D. H., additional, Beise, E. J., additional, Benesch, J., additional, Benmokhtar, F., additional, Bimbot, L., additional, Birchall, J., additional, Bosted, P., additional, Breuer, H., additional, Capuano, C. L., additional, Chao, Y.-C., additional, Coppens, A., additional, Davis, C. A., additional, Ellis, C., additional, Flores, G., additional, Franklin, G., additional, Furget, C., additional, Gaskell, D., additional, Gericke, M. T. W., additional, Grames, J., additional, Guillard, G., additional, Hansknecht, J., additional, Horn, T., additional, Jones, M., additional, King, P. M., additional, Korsch, W., additional, Kox, S., additional, Lee, L., additional, Liu, J., additional, Lung, A., additional, Mammei, J., additional, Martin, J. W., additional, McKeown, R. D., additional, Mihovilovic, M., additional, Micherdzinska, A., additional, Mkrtchyan, H., additional, Muether, M., additional, Page, S. A., additional, Papavassiliou, V., additional, Pate, S. F., additional, Phillips, S. K., additional, Pillot, P., additional, Pitt, M. L., additional, Poelker, M., additional, Quinn, B., additional, Ramsay, W. D., additional, Real, J.-S., additional, Roche, J., additional, Roos, P., additional, Schaub, J., additional, Seva, T., additional, Simicevic, N., additional, Smith, G. R., additional, Spayde, D. T., additional, Stutzman, M., additional, Suleiman, R., additional, Tadevosyan, V., additional, van Oers, W. T. H., additional, Versteegen, M., additional, Voutier, E., additional, Vulcan, W., additional, Wells, S. P., additional, Williamson, S. E., additional, and Wood, S. A., additional

Published
2010
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48. Recent results from theG0experiment

Author

Real, J.S., primary, Androić, D., additional, Armstrong, D.S., additional, Arvieux, J., additional, Bailey, S.L., additional, Beck, D.H., additional, Beise, E.J., additional, Benesch, J., additional, Benmokhtar, F., additional, Bimbot, L., additional, Birchall, J., additional, Bosted, P., additional, Breuer, H., additional, Capuano, C.L., additional, Chao, Y.-C., additional, Coppens, A., additional, Davis, C.A., additional, Ellis, C., additional, Flores, G., additional, Franklin, G., additional, Furget, C., additional, Gaskell, D., additional, Gericke, M.T.W., additional, Grames, J., additional, Guillard, G., additional, Hansknecht, J., additional, Horn, T., additional, Jones, M., additional, King, P.M., additional, Korsch, W., additional, Kox, S., additional, Lee, L., additional, Liu, J., additional, Lung, A., additional, Mammei, J., additional, Martin, J.W., additional, McKeown, R.D., additional, Micherdzinska, A., additional, Mihovilovic, M., additional, Mkrtchyan, H., additional, Muether, M., additional, van Oers, W.T.H., additional, Page, S.A., additional, Papavassiliou, V., additional, Pate, S.F., additional, Phillips, S.K., additional, Pillot, P., additional, Pitt, M.L., additional, Poelker, M., additional, Quinn, B., additional, Ramsay, W.D., additional, Roche, J., additional, Roos, P., additional, Schaub, J., additional, Seva, T., additional, Simicevic, N., additional, Smith, G.R., additional, Spayde, D.T., additional, Stutzman, M., additional, Suleiman, R., additional, Tadevosyan, V., additional, Versteegen, M., additional, Voutier, E., additional, Vulcan, W., additional, Wells, S.P., additional, Williamson, S.E., additional, and Wood, S.A., additional

Published
2010
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