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101. Azimuthal distributions of charged hadrons, pions, and kaons produced in deep-inelastic scattering off unpolarized protons and deuterons

Author: HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Belostotski, S., Blok, H. P., Borissov, A., Bowles, J., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Düren, M., Elbakian, G., Ellinghaus, F., Fantoni, A., Felawka, L., Frullani, S., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lapikás, L., Lehmann, I., Lenisa, P., Ruiz, A. López, Lorenzon, W., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfré, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Murray, M., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Petrosyan, A., Raithel, M., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schäfer, A., Schnell, G., Schüler, K. P., Seitz, B., Shibata, T. -A., Stancari, M., Statera, M., Steijger, J. J. M., Stewart, J., Stinzing, F., Terkulov, A., Truty, R., Trzcinski, A., Tytgat, M., Vandenbroucke, A., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Wang, S., Yaschenko, S., Ye, Z., Yen, S., Yu, W., Zagrebelnyy, V., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: The azimuthal cos{\phi} and cos2{\phi} modulations of the distribution of hadrons produced in unpolarized semi-inclusive deep-inelastic scattering of electrons and positrons off hydrogen and deuterium targets have been measured in the HERMES experiment. For the first time these modulations were determined in a four-dimensional kinematic space for positively and negatively charged pions and kaons separately, as well as for unidentified hadrons. These azimuthal dependences are sensitive to the transverse motion and polarization of the quarks within the nucleon via, e.g., the Cahn, Boer-Mulders and Collins effects.
Published: 2012
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102. Beam-helicity and beam-charge asymmetries associated with deeply virtual Compton scattering on the unpolarised proton

Author: The HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Blok, H. P., Borissov, A., Bowles, J., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Düren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hoek, M., Holler, Y., Imazu, Y., Jackson, H. E., Jo, H. S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Kobayashi, N., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lapikás, L., Lehmann, I., Lenisa, P., Lorenzon, W., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfré, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Muccifora, V., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Petrosyan, A., Raithel, M., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schäfer, A., Schnell, G., Schüler, K. P., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stewart, J., Taroian, S., Terkulov, A., Truty, R., Trzcinski, A., Tytgat, M., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Wang, S., Yaschenko, S., Ye, Z., Yen, S., Yu, W., Zagrebelnyy, V., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: Beam-helicity and beam-charge asymmetries in the hard exclusive leptoproduction of real photons from an unpolarised hydrogen target by a 27.6 GeV lepton beam are extracted from the HERMES data set of 2006-2007 using a missing-mass event selection technique. The asymmetry amplitudes extracted from this data set are more precise than those extracted from the earlier data set of 1996-2005 previously analysed in the same manner by HERMES. The results from the two data sets are compatible with each other. Results from these combined data sets are extracted and constitute the most precise asymmetry amplitude measurements made in the HERMES kinematic region using a missing-mass event selection technique., Comment: (minor changes only compared to arXiv version 1)
Published: 2012
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103. Bright single-photon sources in bottom-up tailored nanowires

Author: Reimer, Michael E., Bulgarini, Gabriele, Akopian, Nika, Hocevar, Moïra, Bavinck, Maaike Bouwes, Verheijen, Marcel A., Bakkers, Erik P. A. M., Kouwenhoven, Leo P., and Zwiller, Val
Subjects: Condensed Matter - Mesoscale and Nanoscale Physics, Physics - Optics
Abstract: The ability to achieve near-unity light extraction efficiency is necessary for a truly deterministic single photon source. The most promising method to reach such high efficiencies is based on embedding single photon emitters in tapered photonic waveguides defined by top-down etching techniques. However, light extraction efficiencies in current top-down approaches are limited by fabrication imperfections and etching induced defects. The efficiency is further tempered by randomly positioned off-axis quantum emitters. Here, we present perfectly positioned single quantum dots on the axis of a tailored nanowire waveguide using bottom-up growth. In comparison to quantum dots in nanowires without waveguide, we demonstrate a 24-fold enhancement in the single photon flux, corresponding to a light extraction efficiency of 42 %. Such high efficiencies in one-dimensional nanowires are promising to transfer quantum information over large distances between remote stationary qubits using flying qubits within the same nanowire p-n junction., Comment: 19 pages, 6 figures
Published: 2012
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104. 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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105. Evidence for the Onset of Color Transparency in $\rho^0$ Electroproduction off Nuclei

Author: Fassi, L. El, Zana, L., Hafidi, K., Holtrop, M., Mustapha, B., Brooks, W. K., Hakobyan, H., Zheng, X., Adhikari, K. P., Adikaram, D., Aghasyan, M., Amaryan, M. J., Anghinolfi, M., Arrington, J., Avakian, H., Baghdasaryan, H., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Bookwalter, C., Branford, D., Briscoe, W. J., Bultmann, S., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Cole, P. L., Contalbrigo, M., Crede, V., D'Angelo, A., Daniel, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Dey, B., Dickson, R., Djalali, C., Dodge, G. E., Doughty, D., Dupre, R., Egiyan, H., Alaoui, A. El, Elouadrhiri, L., Eugenio, P., Fedotov, G., Fegan, S., Gabrielyan, M. Y., Garcon, M., Gevorgyan, N., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Goetz, J. T., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hanretty, C., Heddle, D., Hicks, K., Holt, R. J., Hyde, C. E., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jawalkar, S. S., Keller, D., Khandaker, M., Khetarpal, P., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Kuhn, S. E., Kuleshov, S. V., Kuznetsov, V., Laget, J. M., Lu, H. Y., MacGregor, I. J. D., Mao, Y., Markov, N., Mayer, M., McAndrew, J., McKinnon, B., Meyer, C. A., Mineeva, T., Mirazita, M., Mokeev, V., Moreno, B., Moutarde, H., Munevar, E., Nadel-Turonski, P., Ni, A., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Pappalardo, L., Paremuzyan, R., Park, K., Park, S., Pasyuk, E., Pereira, S. Anefalos, Phelps, E., Pisano, S., Pozdniakov, S., Price, J. W., Procureur, S., Protopopescu, D., Raue, B. A., Reimer, P. E., Ricco, G., Rimal, D., Ripani, M., Ritchie, B. G., Rosner, G., Rossi, P., Sabatie, F., Saini, M. S., Salgado, C., Schott, D., Schumacher, R. A., Seraydaryan, H., Sharabian, Y. G., Smith, E. S., Smith, G. D., Sober, D. I., Sokhan, D., Stepanyan, S. S., Stepanyan, S., Stoler, P., Strauch, S., Taiuti, M., Tang, W., Taylor, C. E., Tedeschi, D. J., Tkachenko, S., Ungaro, M., Vernarsky, B ., Vineyard, M. F., Voskanyan, H., Voutier, E., Watts, D., Weinstein, L. B., Weygand, D. P., Wood, M. H., Zachariou, N., Zhao, B., and Zhao, Z. W.
Subjects: Nuclear Experiment
Abstract: We have measured the nuclear transparency of the incoherent diffractive $A(e,e'\rho^0)$ process in $^{12}$C and $^{56}$Fe targets relative to $^2$H using a 5 GeV electron beam. The nuclear transparency, the ratio of the produced $\rho^0$'s on a nucleus relative to deuterium, which is sensitive to $\rho A$ interaction, was studied as function of the coherence length ($l_c$), a lifetime of the hadronic fluctuation of the virtual photon, and the four-momentum transfer squared ($Q^2$). While the transparency for both $^{12}$C and $^{56}$Fe showed no $l_c$ dependence, a significant $Q^2$ dependence was measured, which is consistent with calculations that included the color transparency effects., Comment: 6 pages and 4 figures
Published: 2012
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106. Measurement of the virtual-photon asymmetry A2 and the spin-structure function g2 of the proton

Author: The HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Belostotski, S., Bianchi, N., Blok, H. P., Borissov, A., Bowles, J., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Düren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lapikás, L., Lehmann, I., Lenisa, P., Ruiz, A. López, Lorenzon, W., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfré, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Muccifora, V., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Petrosyan, A., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schäfer, A., Schnell, G., Schüler, K. P., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stewart, J., Stinzing, F., Taroian, S., Terkulov, A., Truty, R., Trzcinski, A., Tytgat, M., Vandenbroucke, A., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Wang, S., Yaschenko, S., Ye, Z., Yen, S., Zagrebelnyy, V., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: A measurement of the virtual-photon asymmetry A_2(x,Q^2) and of the spin-structure function g_2(x,Q^2) of the proton are presented for the kinematic range 0.004 < x < 0.9 and 0.18 GeV^2 < Q^2 < 20 GeV^2. The data were collected by the HERMES experiment at the HERA storage ring at DESY while studying inclusive deep-inelastic scattering of 27.6 GeV longitudinally polarized leptons off a transversely polarized hydrogen gas target. The results are consistent with previous experimental data from CERN and SLAC. For the x-range covered, the measured integral of g_2(x) converges to the null result of the Burkhardt-Cottingham sum rule. The x^2 moment of the twist-3 contribution to g_2(x) is found to be compatible with zero.
Published: 2011
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107. Updated Report Acceleration of Polarized Protons to 120-150 GeV/c at Fermilab

Author: Courant, E. D., Krisch, A. D., Leonova, M. A., Lin, A. M. T., Liu, J., Lorenzon, W., Nees, D. A., Raymond, R. S., Sivers, D. W., Wong, V. K., Kourbanis, I., Derbenev, Ya. S., Morozov, V. S., Crabb, D. G., Reimer, P. E., O'Fallon, J. R., Fidecaro, G., Fidecaro, M., Hinterberger, F., Troshin, S. M., Ukhanov, M. N., Kondratenko, A. M., and van Oers, W. T. H.
Subjects: Physics - Accelerator Physics, High Energy Physics - Experiment, Nuclear Experiment
Abstract: The SPIN@FERMI collaboration has updated its 1991-95 Reports on the acceleration of polarized protons in Fermilab's Main Injector, which was commissioned by Fermilab. This Updated Report summarizes some updated Physics Goals for a 120-150 GeV/c polarized proton beam. It also contains an updated discussion of the Modifications and Hardware needed for a polarized beam in the Main Injector, along with an updated Schedule and Budget., Comment: 30 pages, 12 figures
Published: 2011

108. Polarization components in $\pi^{0}$ photoproduction at photon energies up to 5.6 GeV

Author: Luo, W., Brash, E. J., Gilman, R., Jones, M. K., Meziane, M., Pentchev, L., Perdrisat, C. F., Puckett, A. J. R., Punjabi, V., Wesselmann, F. R., Ahmidouch, A., Albayrak, I., Aniol, K. A., Arrington, J., Asaturyan, A., Ates, O., Baghdasaryan, H., Benmokhtar, F., Bertozzi, W., Bimbot, L., Bosted, P., Boeglin, W., Butuceanu, C., Carter, P., Chernenko, S., Christy, M. E., Commisso, M., Cornejo, J. C., Covrig, S., Danagoulian, S., Daniel, A., Davidenko, A., Day, D., Dhamija, S., Dutta, D., Ent, R., Frullani, S., Fenker, H., Frlez, E., Garibaldi, F., Gaskell, D., Gilad, S., Goncharenko, Y., Hafidi, K., Hamilton, D., Higinbotham, D. W., Hinton, W., Horn, T., Hu, B., Huang, J., Huber, G. M., Jensen, E., Kang, H., Keppel, C., Khandaker, M., King, P., Kirillov, D., Kohl, M., Kravtsov, V., Kumbartzki, G., Li, Y., Mamyan, V., Margaziotis, D. J., Markowitz, P., Marsh, A., Matulenko, Y., Maxwell, J., Mbianda, G., Meekins, D., Melnik, Y., Miller, J., Mkrtchyan, A., Mkrtchyan, H., Moffit, B., Moreno, O., Mulholland, J., Narayan, A., Nuruzzaman, Nedev, S., Piasetzky, E., Pierce, W., Piskunov, N. M., Prok, Y., Ransome, R. D., Razin, D. S., Reimer, P. E., Reinhold, J., Rondon, O., Shabestari, M., Shahinyan, A., Shestermanov, K., Sirca, S., Sitnik, I., Smykov, L., Smith, G., Solovyev, L., Solvignon, P., Strakovsky, I. I., Subedi, R., Suleiman, R., Tomasi-Gustafsson, E., Vasiliev, A., Veilleux, M., Wood, S., Ye, Z., Zanevsky, Y., Zhang, X., Zhang, Y., Zheng, X., and Zhu, L.
Subjects: Nuclear Experiment
Abstract: We present new data for the polarization observables of the final state proton in the $^{1}H(\vec{\gamma},\vec{p})\pi^{0}$ reaction. These data can be used to test predictions based on hadron helicity conservation (HHC) and perturbative QCD (pQCD). These data have both small statistical and systematic uncertainties, and were obtained with beam energies between 1.8 and 5.6 GeV and for $\pi^{0}$ scattering angles larger than 75$^{\circ}$ in center-of-mass (c.m.) frame. The data extend the polarization measurements data base for neutral pion photoproduction up to $E_{\gamma}=5.6 GeV$. The results show non-zero induced polarization above the resonance region. The polarization transfer components vary rapidly with the photon energy and $\pi^{0}$ scattering angle in c.m. frame. This indicates that HHC does not hold and that the pQCD limit is still not reached in the energy regime of this experiment., Comment: 6 pages and 2 figures
Published: 2011
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109. New measurements of high-momentum nucleons and short-range structures in nuclei

Author: Fomin, N., Arrington, J., Asaturyan, R., Benmokhtar, F., Boeglin, W., Bosted, P., Bruell, A., Bukhari, M. H. S., Chudakov, E., Clasie, B., Connell, S. H., Dalton, M. M., Daniel, A., Day, D. B., Dutta, D., Ent, R., Fassi, L. El, Fenker, H., Filippone, B. W., Garrow, K., Gaskell, D., Hill, C., Holt, R. J., Horn, T., Jones, M. K., Jourdan, J., Kalantarians, N., Keppel, C. E., Kiselev, D., Kotulla, M., Lindgren, R., Lung, A. F., Malace, S., Markowitz, P., McKee, P., Meekins, D. G., Mkrtchyan, H., Navasardyan, T., Niculescu, G., Opper, A. K., Perdrisat, C., Potterveld, D. H., Punjabi, V., Qian, X., Reimer, P. E., Roche, J., Rodriguez, V. M., Rondon, O., Schulte, E., Seely, J., Segbefia, E., Slifer, K., Smith, G. R., Solvignon, P., Tadevosyan, V., Tajima, S., Tang, L., Testa, G., Trojer, R., Tvaskis, V., Vulcan, W. F., Wasko, C., Wesselmann, F. R., Wood, S. A., Wright, J., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data also include the kinematic region where three-nucleon correlations are expected to dominate., Comment: 5 pages, 3 figures. Results from JLab E02-019
Published: 2011
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110. Multidimensional Study of Hadronization in Nuclei

Author: HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Belostotski, S., Bianchi, N., Blok, H. P., Borissov, A., Bowles, J., Brodski, I., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Düren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fabbri, R., Fantoni, A., Felawka, L., Frullani, S., Gapienko, G., Gapienko, V., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Grigoryan, L., Hadjidakis, C., Hartig, M., Hasch, D., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Kobayashi, N., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lapikás, L., Lehmann, I., Lenisa, P., Ruiz, A. López, Lorenzon, W., Lu, X. -G., Lu, X. -R., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfré, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Muccifora, V., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Petrosyan, A., Raithel, M., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schäfer, A., Schnell, G., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stewart, J., Stinzing, F., Taroian, S., Truty, R., Trzcinski, A., Tytgat, M., Vandenbroucke, A., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Vogel, C., Wang, S., Yaschenko, S., Ye, Z., Yen, S., Yu, W., Zagrebelnyy, V., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: Hadron multiplicities in semi-inclusive deep-inelastic scattering were measured on neon, krypton and xenon targets relative to deuterium at an electron(positron)-beam energy of 27.6 GeV at HERMES. These ratios were determined as a function of the virtual-photon energy nu, its virtuality Q2, the fractional hadron energy z and the transverse hadron momentum with respect to the virtual-photon direction pt . Dependences were analysed separately for positively and negatively charged pions and kaons as well as protons and antiprotons in a two-dimensional representation. Compared to the one-dimensional dependences, some new features were observed. In particular, when z > 0.4 positive kaons do not show the strong monotonic rise of the multiplicity ratio with nu as exhibited by pions and negative kaons. Protons were found to behave very differently from the other hadrons.
Published: 2011
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111. New Precision Limit on the Strange Vector Form Factors of the Proton

Author: HAPPEX collaboration, Ahmed, Z., Allada, K., Aniol, K. A., Armstrong, D. S., Arrington, J., Baturin, P., Bellini, V., Benesch, J., Beminiwattha, R., Benmokhtar, F., Canan, M., Camsonne, A., Cates, G. D., Chen, J. -P., Chudakov, E., Cisbani, E., Dalton, M. M., de Jager, C. W., De Leo, R., Deconinck, W., Decowski, P., Deng, X., Deur, A., Dutta, C., Franklin, G. B., Friend, M., Frullani, S., Garibaldi, F., Giusa, A., Glamazdin, A., Golge, S., Grimm, K., Hansen, O., Higinbotham, D. W., Holmes, R., Holmstrom, T., Huang, J., Huang, M., Hyde, C. E., Jen, C. M., Jin, G., Jones, D., Kang, H., King, P., Kowalski, S., Kumar, K. S., Lee, J. H., LeRose, J. J., Liyanage, N., Long, E., McNulty, D., Margaziotis, D., Meddi, F., Meekins, D. G., Mercado, L., Meziani, Z. -E., Michaels, R., Munoz-Camacho, C., Mihovilovic, M., Muangma, N., Myers, K. E., Nanda, S., Narayan, A., Nelyubin, V., Nuruzzaman, Oh, Y., Pan, K., Parno, D., Paschke, K. D., Phillips, S. K., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Rider, K., Riordan, S., Roche, J., Rubin, J., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Silwal, R., Sirca, S., Souder, P. A., Sperduto, M., Subedi, R., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Urciuoli, G. M., Waidyawansa, B., Wang, D., Wexler, J., Wilson, R., Wojtsekhowski, B., Zhan, X., Yan, X., Yao, H., Ye, L., Zhao, B., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: The parity-violating cross-section asymmetry in the elastic scattering of polarized electrons from unpolarized protons has been measured at a four-momentum transfer squared Q2 = 0.624 GeV and beam energy E =3.48 GeV to be A_PV = -23.80 +/- 0.78 (stat) +/- 0.36 (syst) parts per million. This result is consistent with zero contribution of strange quarks to the combination of electric and magnetic form factors G_E^s + 0.517 G_M^s = 0.003 +/- 0.010 (stat) +/- 0.004 (syst) +/- 0.009 (ff), where the third error is due to the limits of precision on the electromagnetic form factors and radiative corrections. With this measurement, the world data on strange contributions to nucleon form factors are seen to be consistent with zero and not more than a few percent of the proton form factors., Comment: 5 pages, 3 figures
Published: 2011
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112. Measurement of double-spin asymmetries associated with deeply virtual Compton scattering on a transversely polarized hydrogen target

Author: The HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Belostotski, S., Bianchi, N., Blok, H. P., Borissov, A., Bowles, J., Brodski, I., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Di Nezza, P., Dueren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fabbri, R., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hartig, M., Hasch, D., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lapikas, L., Lehmann, I., Lenisa, P., Ruiz, A. Lopez, Lorenzon, W., Lu, X. -G., Lu, X. -R., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfre, L., Mao, Y., de la Ossa, B. Marianski A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Raithel, M., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Schaefer, A., Schnell, G., Schueler, K. P., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stinzing, F., Taroian, S., Terkulov, A., Truty, R., Trzcinski, A., Tytgat, M., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Wang, S., Yaschenko, S., Ye, Z., Yen, S., Zagrebelnyy, V., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: Double-spin asymmetries in exclusive electroproduction of real photons from a transversely polarized hydrogen target are measured with respect to the product of target polarization with beam helicity and beam charge, and with respect to the product of target polarization with beam helicity alone. The asymmetries arise from the deeply virtual Compton scattering process and its interference with the Bethe--Heitler process. They are related to the real part of the same combination of Compton form factors as that determining the previously published transverse target single-spin asymmetries through the imaginary part. The results for the double-spin asymmetries are found to be compatible with zero within the uncertainties of the measurement, and are not incompatible with the predictions of the only available GPD-based calculation., Comment: 9 pages, 4 figures, and 3 tables
Published: 2011
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113. Inclusive Measurements of Inelastic Electron and Positron Scattering from Unpolarized Hydrogen and Deuterium Targets

Author: The HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Belostotski, S., Bianchi, N., Blok, H. P., Borissov, A., Bowles, J., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Dueren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fabbri, R., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hill, G., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lamb, R., Lapikas, L., Lehmann, I., Lenisa, P., Linden-Levy, L. A., Ruiz, A. Lopez, Lorenzon, W., Lu, X. -G., Lu, X. -R., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfre, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Muccifora, V., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Pickert, N., Raithel, M., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schaefer, A., Schnell, G., Schueler, K. P., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stenzel, H., Stewart, J., Stinzing, F., Taroian, S., Trzcinski, A., Tytgat, M., Vandenbroucke, A., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Vogel, C., Wang, S., Yaschenko, S., Ye, H., Ye, Z., Yen, S., Yu, W., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: Results of inclusive measurements of inelastic electron and positron scattering from unpolarized protons and deuterons at the HERMES experiment are presented. The structure functions $F_2^p$ and $F_2^d$ are determined using a parameterization of existing data for the longitudinal-to-transverse virtual-photon absorption cross-section ratio. The HERMES results provide data in the ranges $0.006\leq x\leq 0.9$ and 0.1 GeV$^2\leq Q^2\leq$ 20 GeV$^2$, covering the transition region between the perturbative and the non-perturbative regimes of QCD in a so-far largely unexplored kinematic region. They are in agreement with existing world data in the region of overlap. The measured cross sections are used, in combination with data from other experiments, to perform fits to the photon-nucleon cross section using the functional form of the ALLM model. The deuteron-to-proton cross-section ratio is also determined., Comment: 38 pages, 11 Figures, 9 Tables; Fig. 9 modified, Ref. [46] added, minor textual additions on pages 12 and 17
Published: 2011
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114. Semi-Inclusive Charged-Pion Electroproduction off Protons and Deuterons: Cross Sections, Ratios and Access to the Quark-Parton Model at Low Energies

Author: Asaturyan, R., Ent, R., Mkrtchyan, H., Navasardyan, T., Tadevosyan, V., Adams, G. S., Ahmidouch, A., Angelescu, T., Arrington, J., Asaturyan, A., Baker, O. K., Benmouna, N., Bertoncini, C., Blok, H. P., Boeglin, W. U., Bosted, P. E., Breuer, H., Christy, M. E., Connell, S. H., Cui, Y., Dalton, M. M., Danagoulian, S., Day, D., Dunne, J. A., Dutta, D., Khayari, N. El, Fenker, H. C., Frolov, V. V., Gan, L., Gaskell, D., Hafidi, K., Hinton, W., Holt, R. J., Horn, T., Huber, G. M., Hungerford, E., Jiang, X., Jones, M., Joo, K., Kalantarians, N., Kelly, J. J., Keppel, C. E., Kubarovsky, V., Li, Y., Liang, Y., Mack, D., Malace, S. P., Markowitz, P., McGrath, E., McKee, P., Meekins, D. G., Mkrtchyan, A., Moziak, B., Niculescu, G., Niculescu, I., Opper, A. K., Ostapenko, T., Reimer, P. E., Reinhold, J., Roche, J., Rock, S. E., Schulte, E., Segbefia, E., Smith, C., Smith, G. R., Stoler, P., Tang, L., Ungaro, M., Uzzle, A., Vidakovic, S., Villano, A., Vulcan, W. F., Wang, M., Warren, G., Wesselmann, F. R., Wojtsekhowski, B., Wood, S. A., Xu, C., Yuan, L., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: A large set of cross sections for semi-inclusive electroproduction of charged pions ($\pi^\pm$) from both proton and deuteron targets was measured. The data are in the deep-inelastic scattering region with invariant mass squared $W^2$ > 4 GeV$^2$ and range in four-momentum transfer squared $2 < Q^2 < 4$ (GeV/c)$^2$, and cover a range in the Bjorken scaling variable 0.2 < x < 0.6. The fractional energy of the pions spans a range 0.3 < z < 1, with small transverse momenta with respect to the virtual-photon direction, $P_t^2 < 0.2$ (GeV/c)$^2$. The invariant mass that goes undetected, $M_x$ or W', is in the nucleon resonance region, W' < 2 GeV. The new data conclusively show the onset of quark-hadron duality in this process, and the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark --> pion production mechanisms. The x, z and $P_t^2$ dependences of several ratios (the ratios of favored-unfavored fragmentation functions, charged pion ratios, deuteron-hydrogen and aluminum-deuteron ratios for $\pi^+$ and $\pi^-$) have been studied. The ratios are found to be in good agreement with expectations based upon a high-energy quark-parton model description. We find the azimuthal dependences to be small, as compared to exclusive pion electroproduction, and consistent with theoretical expectations based on tree-level factorization in terms of transverse-momentum-dependent parton distribution and fragmentation functions. In the context of a simple model, the initial transverse momenta of $d$ quarks are found to be slightly smaller than for $u$ quarks, while the transverse momentum width of the favored fragmentation function is about the same as for the unfavored one, and both fragmentation widths are larger than the quark widths.
Published: 2011
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115. High Precision Measurement of the Proton Elastic Form Factor Ratio $\mu_pG_E/G_M$ at low $Q^2$

Author: Zhan, X., Allada, K., Armstrong, D. S., Arrington, J., Bertozzi, W., Boeglin, W., Chen, J. -P., Chirapatpimol, K., Choi, S., Chudakov, E., Cisbani, E., Decowski, P., Dutta, C., Frullani, S., Fuchey, E., Garibaldi, F., Gilad, S., Gilman, R., Glister, J., Hafidi, K., Hahn, B., Hansen, J. -O., Higinbotham, D. W., Holmstrom, T., Holt, R. J., Huang, J., Huber, G. M., Itard, F., de Jager, C. W., Jiang, X., Johnson, J., Katich, J., de Leo, R., LeRose, J. J., Lindgren, R., Long, E., Margaziotis, D. J., Beck, S. May-Tal, Meekins, D., Michaels, R., Moffit, B., Norum, B. E., Olson, M., Piasetzky, E., Pomerantz, I., Protopopescu, D., Qian, X., Qiang, Y., Rakhman, A., Ransome, R. D., Reimer, P. E., Reinhold, J., Riordan, S., Ron, G., Saha, A., Sarty, A. J., Sawatzky, B., Schulte, E. C., Shabestari, M., Shahinyan, A., Sirca, S., Solvignon, P., Sparveris, N. F., Strauch, S., Subedi, R., Sulkosky, V., Vilardi, I., Wang, Y., Wojtsekhowski, B., Ye, Z., and Zhang, Y.
Subjects: Nuclear Experiment
Abstract: We report a new, high-precision measurement of the proton elastic form factor ratio \mu_p G_E/G_M for the four-momentum transfer squared Q^2 = 0.3-0.7 (GeV/c)^2. The measurement was performed at Jefferson Lab (JLab) in Hall A using recoil polarimetry. With a total uncertainty of approximately 1%, the new data clearly show that the deviation of the ratio \mu_p G_E/G_M from unity observed in previous polarization measurements at high Q^2 continues down to the lowest Q^2 value of this measurement. The updated global fit that includes the new results yields an electric (magnetic) form factor roughly 2% smaller (1% larger) than the previous global fit in this Q^2 range. We obtain new extractions of the proton electric and magnetic radii, which are ^(1/2)=0.875+/-0.010 fm and ^(1/2)=0.867+/-0.020 fm. The charge radius is consistent with other recent extractions based on the electron-proton interaction, including the atomic hydrogen Lamb shift measurements, which suggests a missing correction in the comparison of measurements of the proton charge radius using electron probes and the recent extraction from the muonic hydrogen Lamb shift., Comment: 12 pages, 3 figures
Published: 2011
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116. Ratios of Helicity Amplitudes for Exclusive rho-0 Electroproduction

Author: The HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Belostotski, S., Bianchi, N., Blok, H. P., Borissov, A., Bowles, J., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Dueren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fabbri, R., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hill, G., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Kobayashi, N., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lamb, R., Lapikas, L., Lehmann, I., Lenisa, P., Linden-Levy, L. A., Ruiz, A. Lopez, Lorenzon, W., Lu, X. -G., Lu, X. -R., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfre, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Muccifora, V., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Pickert, N., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schaefer, A., Schnell, G., Schueler, K. P., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stinzing, F., Taroian, S., Terkulov, A., Trzcinski, A., Tytgat, M., Vandenbroucke, A., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Wang, S., Yaschenko, S., Yen, S., Yu, W., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: Exclusive rho^0-meson electroproduction is studied in the HERMES experiment, using a 27.6 GeV longitudinally polarized electron/positron beam and unpolarized hydrogen and deuterium targets in the kinematic region 0.5 GeV^2 < Q^2 < 7.0 GeV^2, 3.0 GeV < W < 6.3 GeV, and -t' < 0.4 GeV^2. Real and imaginary parts of the ratios of the natural-parity-exchange helicity amplitudes T_{11} (\gamma^*_T --> \rho_T), T_{01} (\gamma^*_T --> \rho_L), T_{10} (\gamma^*_L --> \rho_T), and T_{1-1} (\gamma^*_{-T} -->\rho_T) to T_{00} (\gamma^*_L --> \rho_L) are extracted from the data. For the unnatural-parity-exchange amplitude U_{11}, the ratio |U_{11}/T_{00}| is obtained. The Q^2 and t' dependences of these ratios are presented and compared with perturbative QCD predictions., Comment: 27 pages, 8 tables, 13 figures; minor textual changes on pages 2, 3,9, 10, 11, and some changes to the list of references
Published: 2010
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117. Search for effects beyond the Born approximation in polarization transfer observables in $\vec{e}p$ elastic scattering

Author: Meziane, M., Brash, E. J., Gilman, R., Jones, M. K., Luo, W., Pentchev, L., Perdrisat, C. F., Puckett, A. J. R., Punjabi, V., Wesselmann, F. R., Ahmidouch, A., Albayrak, I., Aniol, K. A., Arrington, J., Asaturyan, A., Ates, O., Baghdasaryan, H., Benmokhtar, F., Bertozzi, W., Bimbot, L., Bosted, P., Boeglin, W., Butuceanu, C., Carter, P., Chernenko, S., Christy, E., Commisso, M., Cornejo, J. C., Covrig, S., Danagoulian, S., Daniel, A., Davidenko, A., Day, D., Dhamija, S., Dutta, D., Ent, R., Frullani, S., Fenker, H., Frlez, E., Garibaldi, F., Gaskell, D., Gilad, S., Goncharenko, Y., Hafidi, K., Hamilton, D., Higinbotham, D. W., Hinton, W., Horn, T., Hu, B., Huang, J., Huber, G. M., Jensen, E., Kang, H., Keppel, C., Khandaker, M., King, P., Kirillov, D., Kohl, M., Kravtsov, V., Kumbartzki, G., Li, Y., Mamyan, V., Margaziotis, D. J., Markowitz, P., Marsh, A., Matulenko, Y., Maxwell, J., Mbianda, G., Meekins, D., Melnik, Y., Miller, J., Mkrtchyan, A., Mkrtchyan, H., Moffit, B., Moreno, O., Mulholland, J., Narayan, A., Nuruzzaman, Nedev, S., Piasetzky, E., Pierce, W., Piskunov, N. M., Prok, Y., Ransome, R. D., Razin, D. S., Reimer, P. E., Reinhold, J., Rondon, O., Shabestari, M., Shahinyan, A., Shestermanov, K., Sirca, S., Sitnik, I., Smykov, L., Smith, G., Solovyev, L., Solvignon, P., Subedi, R., Suleiman, R., Tomasi-Gustafsson, E., Vasiliev, A., Vanderhaeghen, M., Veilleux, M., Wojtsekhowski, B. B., Wood, S., Ye, Z., Zanevsky, Y., Zhang, X., Zhang, Y., Zheng, X., and Zhu, L.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton electric to magnetic form factor ratio, $G_{E}/G_{M}$, obtained separately from cross section and polarization transfer measurements. One possible explanation for this difference is a two-photon-exchange (TPEX) contribution. In an effort to search for effects beyond the one-photon-exchange or Born approximation, we report measurements of polarization transfer observables in the elastic $H(\vec{e},e'\vec{p})$ reaction for three different beam energies at a fixed squared momentum transfer $Q^2 = 2.5$ GeV$^2$, spanning a wide range of the virtual photon polarization parameter, $\epsilon$. From these measured polarization observables, we have obtained separately the ratio $R$, which equals $\mu_p G_{E}/G_{M}$ in the Born approximation, and the longitudinal polarization transfer component $P_\ell$, with statistical and systematic uncertainties of $\Delta R \approx \pm 0.01 \mbox{(stat)} \pm 0.013 \mbox{(syst)}$ and $\Delta P_\ell/P^{Born}_{\ell} \approx \pm 0.006 \mbox{(stat)}\pm 0.01 \mbox{(syst)}$. The ratio $R$ is found to be independent of $\epsilon$ at the 1.5% level, while the $\epsilon$ dependence of $P_\ell$ shows an enhancement of $(2.3 \pm 0.6) %$ relative to the Born approximation at large $\epsilon$.
Published: 2010
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118. Single photon emission and detection at the nanoscale utilizing semiconductor nanowires

Author: Reimer, Michael E., van Kouwen, Maarten P., Barkelid, Maria, Hocevar, Moira, van Weert, Maarten. H. M., Algra, Rienk E., Bakkers, Erik P. A. M., Bjork, Mikael T., Schmid, Heinz, Riel, Heike, Kouwenhoven, Leo P., and Zwiller, Val
Subjects: Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science
Abstract: We report recent progress toward on-chip single photon emission and detection in the near infrared utilizing semiconductor nanowires. Our single photon emitter is based on a single InAsP quantum dot embedded in a p-n junction defined along the growth axis of an InP nanowire. Under forward bias, light is emitted from the single quantum dot by electrical injection of electrons and holes. The optical quality of the quantum dot emission is shown to improve when surrounding the dot material by a small intrinsic section of InP. Finally, we report large multiplication factors in excess of 1000 from a single Si nanowire avalanche photodiode comprised of p-doped, intrinsic, and n-doped sections. The large multiplication factor obtained from a single Si nanowire opens up the possibility to detect a single photon at the nanoscale., Comment: 11 pages, 7 figures
Published: 2010
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119. Measurement of azimuthal asymmetries associated with deeply virtual Compton scattering on a longitudinally polarized deuterium target

Author: The HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Belostotski, S., Bianchi, N., Blok, H. P., Borissov, A., Bowles, J., Brodski, I., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Dueren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hill, G., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Jackson, H. E., Jgoun, A., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Kobayashi, N., Korotkov, V., Kozlov, V., Krauss, B., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lamb, R., Lapikas, L., Lehmann, I., Lenisa, P., Linden-Levy, L. A., Ruiz, A. Lopez, Lorenzon, W., Lu, X. -G., Lu, X. -R., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfre, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Movsisyan, A., Muccifora, V., Murray, M., Mueller, D., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Pickert, N., Raithel, M., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schaefer, A., Schnell, G., Schueler, K. P., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stenzel, H., Stewart, J., Stinzing, F., Taroian, S., Terkulov, A., Trzcinski, A., Tytgat, M., Vandenbroucke, A., Van der Nat, P. B., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Vogel, C., Wang, S., Yaschenko, S., Ye, Z., Yen, S., Yu, W., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: Azimuthal asymmetries in exclusive electroproduction of a real photon from a longitudinally polarized deuterium target are measured with respect to target polarization alone and with respect to target polarization combined with beam helicity and/or beam charge. The asymmetries appear in the distribution of the real photons in the azimuthal angle $\phi$ around the virtual photon direction, relative to the lepton scattering plane. The asymmetries arise from the deeply virtual Compton scattering process and its interference with the Bethe-Heitler process. The results for the beam-charge and beam-helicity asymmetries from a tensor polarized deuterium target with vanishing vector polarization are shown to be compatible with those from an unpolarized deuterium target, which is expected for incoherent scattering dominant at larger momentum transfer. Furthermore, the results for the single target-spin asymmetry and for the double-spin asymmetry are found to be compatible with the corresponding asymmetries previously measured on a hydrogen target. For coherent scattering on the deuteron at small momentum transfer to the target, these findings imply that the tensor contribution to the cross section is small. Furthermore, the tensor asymmetry is found to be compatible with zero., Comment: 33 pages, 7 figures, 7 tables; minor textual changes on pages 5 and 27, additional Table 2 added on page 10
Published: 2010
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120. Scaling of the F_2 structure function in nuclei and quark distributions at x>1

Author: Fomin, N., Arrington, J., Day, D. B., Gaskell, D., Daniel, A., Seely, J., Asaturyan, R., Benmokhtar, F., Boeglin, W., Boillat, B., Bosted, P., Bruell, A., Bukhari, M. H. S., Christy, M. E., Chudakov, E., Clasie, B., Connell, S. H., Dalton, M. M., Dutta, D., Ent, R., Fassi, L. El, Fenker, H., Filippone, B. W., Garrow, K., Hill, C., Holt, R. J., Horn, T., Jones, M. K., Jourdan, J., Kalantarians, N., Keppel, C. E., Kiselev, D., Kotulla, M., Lindgren, R., Lung, A. F., Malace, S., Markowitz, P., McKee, P., Meekins, D. G., Miyoshi, T., Mkrtchyan, H., Navasardyan, T., Niculescu, G., Okayasu, Y., Opper, A. K., Perdrisat, C., Potterveld, D. H., Punjabi, V., Qian, X., Reimer, P. E., Roche, J., Rodriguez, V. M., Rondon, O., Schulte, E., Segbefia, E., Slifer, K., Smith, G. R., Solvignon, P., Tadevosyan, V., Tajima, S., Tang, L., Testa, G., Trojer, R., Tvaskis, V., Vulcan, W. F., Wasko, C., Wesselmann, F. R., Wood, S. A., Wright, J., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for $x>1$, which is sensitive to short range contributions to the nuclear wave-function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the `super-fast' quarks probed at x>1. The falloff at x>1 is noticeably stronger in ^2H and ^3He, but nearly identical for all heavier nuclei., Comment: 5 pages, 4 figures, to be submitted to physical review
Published: 2010
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121. Measurements of the Electric Form Factor of the Neutron up to Q2=3.4 GeV2 using the Reaction He3(e,e'n)pp

Author: Riordan, S., Abrahamyan, S., Craver, B., Kelleher, A., Kolarkar, A., Miller, J., Cates, G. D., Liyanage, N., Wojtsekhowski, B., Acha, A., Allada, K., Anderson, B., Aniol, K. A., Annand, J. R. M., Arrington, J., Averett, T., Beck, A., Bellis, M., Boeglin, W., Breuer, H., Calarco, J. R., Camsonne, A., Chen, J. P., Chudakov, E., Coman, L., Crowe, B., Cusanno, F., Day, D., Degtyarenko, P., Dolph, P. A. M., Dutta, C., Ferdi, C., Fernandez-Ramirez, C., Feuerbach, R., Fraile, L. M., Franklin, G., Frullani, S., Fuchs, S., Garibaldi, F., Gevorgyan, N., Gilman, R., Glamazdin, A., Gomez, J., Grimm, K., Hansen, J. O., Herraiz, J. L., Higinbotham, D. W., Holmes, R., Holmstrom, T., Howell, D., deJager, C. W., Jiang, X., Jones, M. K., Katich, J., Kaufman, L. J., Khandaker, M., Kelly, J. J., Kiselev, D., Korsch, W., LeRose, J., Lindgren, R., Markowitz, P., Margaziotis, D. J., Beck, S. May-Tal, Mayilyan, S., McCormick, K., Meziani, Z. E., Michaels, R., Moffit, B., Nanda, S., Nelyubin, V., Ngo, T., Nikolenko, D. M., Norum, B., Pentchev, L., Perdrisat, C. F., Piasetzky, E., Pomatsalyuk, R., Protopopescu, D., Puckett, A. J. R., Punjabi, V. A., Qian, X., Qiang, Y., Quinn, B., Rachek, I., Ransome, R. D., Reimer, P. E., Reitz, B., Roche, J., Ron, G., Rondon, O., Rosner, G., Saha, A., Sargsian, M., Sawatzky, B., Segal, J., Shabestari, M., Shahinyan, A., Shestakov, Yu., Singh, J., Sirca, S., Souder, P., Stepanyan, S., Stibunov, V., Sulkosky, V., Tajima, S., Tobias, W. A., Udias, J. M., Urciuoli, G. M., Vlahovic, B., Voskanyan, H., Wang, K., Wesselmann, F. R., Vignote, J. R., Wood, S. A., Wright, J., Yao, H., and Zhu, X.
Subjects: Nuclear Experiment
Abstract: The electric form factor of the neutron was determined from studies of the reaction He3(e,e'n)pp in quasi-elastic kinematics in Hall A at Jefferson Lab. Longitudinally polarized electrons were scattered off a polarized target in which the nuclear polarization was oriented perpendicular to the momentum transfer. The scattered electrons were detected in a magnetic spectrometer in coincidence with neutrons that were registered in a large-solid-angle detector. More than doubling the Q2-range over which it is known, we find GEn = 0.0225 +/- 0.0017 (stat) +/- 0.0024 (syst), 0.0200 +/- 0.0023 +/- 0.0018, and 0.0142 +/- 0.0019 +/- 0.0013 for Q2 = 1.72, 2.48, and 3.41 GeV2, respectively., Comment: submitted to PRL
Published: 2010
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122. Effects of transversity in deep-inelastic scattering by polarized protons

Author: HERMES collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Bacchetta, A., Belostotski, S., Bianchi, N., Blok, H. P., Borissov, A., Bowles, J., Brodski, I., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Dueren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Elschenbroich, U., Fabbri, R., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hill, G., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Izotov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Kobayashi, N., Korotkov, V., Kozlov, V., Kravchenko, P., Lagamba, L., Lamb, R., Lapikas, L., Lehmann, I., Lenisa, P., Linden-Levy, L. A., Ruiz, A. Lopez, Lorenzon, W., Lu, X. -G., Lu, X. -R., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfre, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Pickert, N., Raithel, M., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schaefer, A., Schnell, G., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stenzel, H., Stewart, J., Stinzing, F., Taroian, S., Terkulov, A., Trzcinski, A., Tytgat, M., van der Nat, P. B., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Vogel, C., Wang, S., Yaschenko, S., Ye, H., Ye, Z., Yen, S., Yu, W., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: Single-spin asymmetries for pions and charged kaons are measured in semi-inclusive deep-inelastic scattering of positrons and electrons off a transversely nuclear-polarized hydrogen target. The dependence of the cross section on the azimuthal angles of the target polarization (phi_S)and the produced hadron (phi) is found to have a substantial sin(phi+phi_S) modulation for the production of pi+, pi- and K+. This Fourier component can be interpreted in terms of non-zero transversity distribution functions and non-zero favored and disfavored Collins fragmentation functions with opposite sign. For pi0 and K- production the amplitude of this Fourier component is consistent with zero., Comment: 7 pages, 3 figures
Published: 2010
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123. Exclusive Leptoproduction of Real Photons on a Longitudinally Polarised Hydrogen Target

Author: The HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Ball, B., Belostotski, S., Bianchi, N., Blok, H. P., Boettcher, H., Borissov, A., Bowles, J., Brodski, I., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., Dueren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fabbri, R., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hill, G., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Izotov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Kobayashi, N., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijne, V. G., Lagamba, L., Lamb, R., Lapikas, L., Lehmann, I., Lenisa, P., Linden-Levy, L. A., Lopez~Ruiz, A., Lorenzon, W., Lu, X. -G., Lu, X. -R., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Manfre, L., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Muccifora, V., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Pickert, N., Raithel, M., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Schaefer, A., Schnell, G., Schueler, K. P., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stenzel, H., Stewart, J., Stinzing, F., Taroian, S., Terkulov, A., Trzcinski, A., Tytgat, M., Vandenbroucke, A., van der Nat, P. B., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Vogel, C., Wang, S., Yaschenko, S., Ye, H., Ye, Z., Yen, S., Yu, W., Zeiler, D., Zihlmann, B., and Zupranski, P.
Subjects: High Energy Physics - Experiment
Abstract: Polarisation asymmetries are measured for the hard exclusive leptoproduction of real photons from a longitudinally polarised hydrogen target. These asymmetries arise from the deeply virtual Compton scattering and Bethe-Heitler processes. From the data are extracted two asymmetries in the azimuthal distribution of produced real photons about the direction of the exchanged virtual photon: A_UL with respect to the target polarisation and A_LL with respect to the product of the beam and target polarisations. Results for both asymmetries are compared to the predictions from a generalised parton distribution model. The sin(phi) and cos(0*phi) amplitudes observed respectively for the A_UL and A_LL asymmetries are compatible with the sizeable predictions from the model. Unexpectedly, a sin(2*phi) modulation in the A_UL asymmetry with a magnitude similar to that of the sin(phi) modulation is observed., Comment: 18 pages, 2 figures, 5 tables
Published: 2010
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124. Neutral Pion Electroproduction in the Resonance Region at High $Q^2$

Author: Villano, A. N., Stoler, P., Bosted, P. E., Connell, S. H., Dalton, M. M., Jones, M. K., Kubarovsky, V., Adams, G. S, Ahmidouch, A., Arrington, J., Asaturyan, R., Baker, O. K., Breuer, H., Christy, M. E., Danagoulian, S., Day, D., Dunne, J. A., Dutta, D., Ent, R., Fenker, H. C., Frolov, V. V., Gan, L., Gaskell, D., Hinton, W., Holt, R. J., Horn, T., Huber, G. M., Joo, K., Kalantarians, N., Keppel, C. E., Li, Y., Lung, A., Mack, D., Malace, S., Markowitz, P., Meekins, D. G., Mkrtchyan, H., Napolitano, J., Niculescu, G., Niculescu, I., Potterveld, D. H., Reimer, Paul E., Reinhold, J., Roche, J., Rock, S. E., Smith, G. R., Stepanyan, S., Tadevosyan, V., Tvaskis, V., Ungaro, M., Uzzle, A., Vidakovic, S., Wesselmann, F. R., Wojtsekhowski, B., Wood, S. A., Yuan, L., Zheng, X., and Zhu, H.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: The process $ep \to e^{\prime}p^{\prime}\pi^0$ has been measured at $Q^2$ = 6.4 and 7.7 GeV/c$^2$)$^2$ in Jefferson Lab's Hall C. Unpolarized differential cross sections are reported in the virtual photon-proton center of mass frame considering the process $\gamma^{\ast}p \to p^{\prime}\pi^0$. Various details relating to the background subtractions, radiative corrections and systematic errors are discussed. The usefulness of the data with regard to the measurement of the electromagnetic properties of the well known $\Delta(1232)$ resonance is covered in detail. Specifically considered are the electromagnetic and scalar-magnetic ratios $R_{EM}$ and $R_{SM}$ along with the magnetic transition form factor $G_M^{\ast}$. It is found that the rapid fall off of the $\Delta(1232)$ contribution continues into this region of momentum transfer and that other resonances, Comment: 41 pages including numerical cross section tables, updates include new phenomenological fit for multipole extraction in addition to simplified previous method, These fits are seen in figures 24,26 and 27 and the values are reported in Table VIII
Published: 2009
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125. New measurements of the EMC effect in very light nuclei

Author: Seely, J., Daniel, A., Gaskell, D., Arrington, J., Fomin, N., Solvignon, P., Asaturyan, R., Benmokhtar, F., Boeglin, W., Boillat, B., Bosted, P., Bruell, A., Bukhari, M. H. S., Christy, M. E., Clasie, B., Connell, S., Dalton, M., Day, D., Dunne, J., Dutta, D., Fassi, L. El, Ent, R., Fenker, H., Filippone, B. W., Gao, H., Hill, C., Holt, R. J., Horn, T., Hungerford, E., Jones, M. K., Jourdan, J., Kalantarians, N., Keppel, C. E., Kiselev, D., Kotulla, M., Lee, C., Lung, A. F., Malace, S., Meekins, D. G., Mertens, T., Mkrtchyan, H., Navasardyan, T., Niculescu, G., Niculescu, I., Nomura, H., Okayasu, Y., Opper, A. K., Perdrisat, C., Potterveld, D. H., Punjabi, V., Qian, X., Reimer, P. E., Roche, J., Rodriguez, V. M., Rondon, O., Schulte, E., Segbefia, E., Slifer, K., Smith, G. R., Tadevosyan, V., Tajima, S., Tang, L., Testa, G., Trojer, R., Tvaskis, V., Vulcan, W. F., Wesselmann, F. R., Wood, S. A., Wright, J., Yuan, L., and Zheng, X.
Subjects: Nuclear Experiment, High Energy Physics - Phenomenology
Abstract: New Jefferson Lab data are presented on the nuclear dependence of the inclusive cross section from 2H, 3He, 4He, 9Be and 12C for 0.3
Published: 2009
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126. An experimental program with high duty-cycle polarized and unpolarized positron beams at Jefferson Lab

Author: Accardi, A., Afanasev, A., Albayrak, I., Ali, S. F., Amaryan, M., Annand, J. R. M., Arrington, J., Asaturyan, A., Atac, H., Avakian, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Barion, L., Battaglieri, M., Bellini, V., Beminiwattha, R., Benmokhtar, F., Berdnikov, V. V., Bernauer, J. C., Bertone, V., Bianconi, A., Biselli, A., Bisio, P., Blunden, P., Boer, M., Bondì, M., Brinkmann, K.-T., Briscoe, W. J., Burkert, V., Cao, T., Camsonne, A., Capobianco, R., Cardman, L., Carmignotto, M., Caudron, M., Causse, L., Celentano, A., Chatagnon, P., Chen, J.-P., Chetry, T., Ciullo, G., Cline, E., Cole, P. L., Contalbrigo, M., Costantini, G., D’Angelo, A., Darmé, L., Day, D., Defurne, M., De Napoli, M., Deur, A., De Vita, R., D’Hose, N., Diehl, S., Diefenthaler, M., Dongwi, B., Dupré, R., Dutrieux, H., Dutta, D., Ehrhart, M., El Fassi, L., Elouadrhiri, L., Ent, R., Erler, J., Fernando, I. P., Filippi, A., Flay, D., Forest, T., Fuchey, E., Fucini, S., Furletova, Y., Gao, H., Gaskell, D., Gasparian, A., Gautam, T., Girod, F.-X., Gnanvo, K., Grames, J., Grauvogel, G. N., Gueye, P., Guidal, M., Habet, S., Hague, T. J., Hamilton, D. J., Hansen, O., Hasell, D., Hattawy, M., Higinbotham, D. W., Hobart, A., Horn, T., Hyde, C. E., Ibrahim, H., Ilyichev, A., Italiano, A., Joo, K., Joosten, S. J., Khachatryan, V., Kalantarians, N., Kalicy, G., Karky, B., Keller, D., Keppel, C., Kerver, M., Khandaker, M., Kim, A., Kim, J., King, P. M., Kinney, E., Klimenko, V., Ko, H.-S., Kohl, M., Kozhuharov, V., Kriesten, B. T., Krnjaic, G., Kubarovsky, V., Kutz, T., Lanza, L., Leali, M., Lenisa, P., Liyanage, N., Liu, Q., Liuti, S., Mammei, J., Mantry, S., Marchand, D., Markowitz, P., Marsicano, L., Mascagna, V., Mazouz, M., McCaughan, M., McKinnon, B., McNulty, D., Melnitchouk, W., Metz, A., Meziani, Z.-E., Migliorati, S., Mihovilovič, M., Milner, R., Mkrtchyan, A., Mkrtchyan, H., Movsisyan, A., Moutarde, H., Muhoza, M., Camacho, C. Muñoz, Murphy, J., Nadel-Turoński, P., Nardi, E., Nazeer, J., Niccolai, S., Niculescu, G., Novotny, R., Owens, J. F., Paolone, M., Pappalardo, L., Paremuzyan, R., Pasquini, B., Pasyuk, E., Patel, T., Pegg, I., Peng, C., Perera, D., Poelker, M., Price, K., Puckett, A. J. R., Raggi, M., Randazzo, N., Rashad, M. N. H., Rathnayake, M., Raue, B., Reimer, P. E., Rinaldi, M., Rizzo, A., Roblin, Y., Roche, J., Rondon-Aramayo, O., Sabatié, F., Salmè, G., Santopinto, E., Santos Estrada, R., Sawatzky, B., Schmidt, A., Schweitzer, P., Scopetta, S., Sergeyeva, V., Shabestari, M., Shahinyan, A., Sharabian, Y., Širca, S., Smith, E. S., Sokhan, D., Somov, A., Sparveris, N., Spata, M., Spiesberger, H., Spreafico, M., Stepanyan, S., Stoler, P., Strakovsky, I., Suleiman, R., Suresh, M., Sznajder, P., Szumila-Vance, H., Tadevosyan, V., Tadepalli, A. S., Thomas, A. W., Tiefenback, M., Trotta, R., Ungaro, M., Valente, P., Vanderhaeghen, M., Venturelli, L., Voskanyan, H., Voutier, E., Wojtsekhowski, B., Wood, M. H., Wood, S., Xie, J., Xiong, W., Ye, Z., Yurov, M., Zaunick, H.-G., Zhamkochyan, S., Zhang, J., Zhang, S., Zhao, S., Zhao, Z. W., Zheng, X., Zhou, J., and Zorn, C.
Published: 2021
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127. Lost in translation: no effect of repeated optogenetic cortico-striatal stimulation on compulsivity in rats

Author: de Oliveira, Amanda R., Reimer, Adriano E., Simandl, Gregory J., Nagrale, Sumedh S., and Widge, Alik S.
Published: 2021
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128. Measurement of Angular Distributions of Drell-Yan Dimuons in $p + p$ Interactions at 800 GeV/c

Author: Zhu, L. Y., Peng, J. C., Reimer, P. E., Awes, T. C., Brooks, M. L., and Brown, C. N.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: We report a measurement of the angular distributions of Drell-Yan dimuons produced using an 800 GeV/c proton beam on a hydrogen target. The polar and azimuthal angular distribution parameters have been extracted over the kinematic range $4.5 < m_{\mu \mu} < 15$ GeV/c$^2$ (excluding the $\Upsilon$ resonance region), $0 < p_T < 4 $ GeV/c, and $0 < x_F < 0.8$. The $p+p$ angular distributions are similar to those of $p+d$, and both data sets are compared with models which attribute the $\cos 2 \phi$ distribution either to the presence of the transverse-momentum-dependent Boer-Mulders structure function $h_1^\perp$ or to QCD effects. The data indicate the presence of both mechanisms. The validity of the Lam-Tung relation in $p+p$ Drell-Yan is also tested., Comment: 4 pages, 3 figures
Published: 2008
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129. High Resolution Spectroscopy of 16N_Lambda by Electroproduction

Author: Cusanno, F., Urciuoli, G. M., Acha, A., Ambrozewicz, P., Aniol, K. A., Baturin, P., Bertin, P. Y., Benaoum, H., Blomqvist, K. I., Boeglin, W. U., Breuer, H., Brindza, P., Bydzovsky, P., Camsonne, A., Chang, C. C., Chen, J. -P., Choi, Seonho, Chudakov, E. A., Cisbani, E., Colilli, S., Coman, L., Craver, B. J., De Cataldo, G., de Jager, C. W., De Leo, R., Deur, A. P., Ferdi, C., Feuerbach, R. J., Folts, E., Fratoni, R., Frullani, S., Garibaldi, F., Gayou, O., Giuliani, F., Gomez, J., Gricia, M., Hansen, J. O., Hayes, D., Higinbotham, D. W., Holmstrom, T. K., Hyde, C. E., Ibrahim, H. F., Iodice, M., Jiang, X., Kaufman, L. J., Kino, K., Kross, B., Lagamba, L., LeRose, J. J., Lindgren, R. A., Lucentini, M., Margaziotis, D. J., Markowitz, P., Marrone, S., Meziani, Z. E., McCormick, K., Michaels, R. W., Millener, D. J., Miyoshi, T., Moffit, B., Monaghan, P. A., Moteabbed, M., Camacho, C. Munoz, Nanda, S., Nappi, E., Nelyubin, V. V., Norum, B. E., Okasyasu, Y., Paschke, K. D., Perdrisat, C. F., Piasetzky, E., Punjabi, V. A., Qiang, Y., Raue, B., Reimer, P. E., Reinhold, J., Reitz, B., Roche, R. E., Rodriguez, V. M., Saha, A., Santavenere, F., Sarty, A. J., Segal, J., Shahinyan, A., Singh, J., Sirca, S., Snyder, R., Solvignon, P. H., Sotona, M., Subedi, R., Sulkosky, V. A., Suzuki, T., Ueno, H., Ulmer, P. E., Veneroni, P., Voutier, E., Wojtsekhowski, B. B., Zeng, X., and Zorn, C.
Subjects: Nuclear Experiment
Abstract: An experimental study of the 16O(e,e'K^+)16N_Lambda reaction has been performed at Jefferson Lab. A thin film of falling water was used as a target. This permitted a simultaneous measurement of the p(e,e'K^+)Lambda,Sigma_0 exclusive reactions and a precise calibration of the energy scale. A ground-state binding energy of 13.76 +/- 0.16 MeV was obtained for 16N_Lambda with better precision than previous measurements on the mirror hypernucleus 16O_Lambda. Precise energies have been determined for peaks arising from a Lambda in s and p orbits coupled to the p_{1/2} and p_{3/2} hole states of the 15N core nucleus., Comment: 5 pages, 3 figures, 2 tables
Published: 2008
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130. Tuning the exciton g-factor in single InAs/InP quantum dots

Author: Kim, D., Sheng, W., Poole, P. J., Dalacu, D., Lefebvre, J., Lapointe, J., Reimer, M. E., Aers, G. C., and Williams, R. L.
Subjects: Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science
Abstract: Photoluminescence data from single, self-assembled InAs/InP quantum dots in magnetic fields up to 7 T are presented. Exciton g-factors are obtained for dots of varying height, corresponding to ground state emission energies ranging from 780 meV to 1100 meV. A monotonic increase of the g-factor from -2 to +1.2 is observed as the dot height decreases. The trend is well reproduced by sp3 tight binding calculations, which show that the hole g-factor is sensitive to confinement effects through orbital angular momentum mixing between the light-hole and heavy-hole valence bands. We demonstrate tunability of the exciton g-factor by manipulating the quantum dot dimensions using pyramidal InP nanotemplates.
Published: 2008
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131. Electroproduction of Eta Mesons in the S11(1535) Resonance Region at High Momentum Transfer

Author: Dalton, M. M., Adams, G. S., Ahmidouch, A., Angelescu, T., Arrington, J., Asaturyan, R., Baker, O. K., Benmouna, N., Bertoncini, C., Boeglin, W. U., Bosted, P. E., Breuer, H., Christy, M. E., Connell, S. H., Cui, Y., Danagoulian, S., Day, D., Dodario, T., Dunne, J. A., Dutta, D., Khayari, N. El, Ent, R., Fenker, H. C., Frolov, V. V., Gan, L., Gaskell, D., Hafidi, K., Hinton, W., Holt, R. J., Horn, T., Huber, G. M., Hungerford, E., Jiang, X., Jones, M. K., Joo, K., Kalantarians, N., Kelly, J. J., Keppel, C. E., Kubarovsky, V., Li, Y., Liang, Y., Malace, S., Markowitz, P., McKee, P., Meekins, D. G., Mkrtchyan, H., Moziak, B., Navasardyan, T., Niculescu, G., Niculescu, I., Opper, A. K., Ostapenko, T., Reimer, P. E., Reinhold, J., Roche, J., Rock, S. E., Schulte, E., Segbefia, E., Smith, C., Smith, G. R., Stoler, P., Tadevosyan, V., Tang, L., Tvaskis, V., Ungaro, M., Uzzle, A., Vidakovic, S., Villano, A., Vulcan, W. F., Wang, M., Warren, G., Wesselmann, F. R., Wojtsekhowski, B., Wood, S. A., Xu, C., Yuan, L., Zheng, X., and Zhu, H.
Subjects: High Energy Physics - Experiment
Abstract: The differential cross-section for the process p(e,e'p)eta has been measured at Q2 ~ 5.7 and 7.0 (GeV/c)2 for centre-of-mass energies from threshold to 1.8 GeV, encompassing the S11(1535) resonance, which dominates the channel. This is the highest momentum transfer measurement of this exclusive process to date. The helicity-conserving transition amplitude A_1/2, for the production of the S11(1535) resonance, is extracted from the data. Within the limited Q2 now measured, this quantity appears to begin scaling as 1/Q3 - a predicted, but not definitive, signal of the dominance of perturbative QCD, at Q2 ~ 5 (GeV/c)2., Comment: LaTeX, 30 pages, 29 figures, uses longtable.sty, slashbox.sty, ifthen.sty; (v2) corrected figure inclusions; (v3) changes in filenames for prc and added Report-no; (v4) correction based on comments from referee {small changes to abstract and conclusion, inserted figure 9, other small changes to the text} (v5) very minor additions to improve clarity
Published: 2008
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132. Transverse momentum dependence of semi-inclusive pion production

Author: Mkrtchyan, H., Bosted, P. E., Adams, G. S., Ahmidouch, A., Angelescu, T., Arrington, J., Asaturyan, R., Baker, O. K., Benmouna, N., Bertoncini, C., Blok, H. P., Boeglin, W. U., Breuer, H., Christy, M. E., Connell, S. H., Cui, Y., Dalton, M. M., Danagoulian, S., Day, D., Dodario, T., Dunne, J. A., Dutta, D., Khayari, N. El, Ent, R., Fenker, H. C., Frolov, V. V., Gan, L., Gaskell, D., Hafidi, K., Hinton, W., Holt, R. J., Horn, T., Huber, G. M., Hungerford, E., Jiang, X., Jones, M., Joo, K., Kalantarians, N., Kelly, J. J., Keppel, C. E., Kubarovsky, V., Li, Y., Liang, Y., Malace, S., Markowitz, P., McGrath, E., McKee, P., Meekins, D. G., Moziak, B., Navasardyan, T., Niculescu, G., Niculescu, I., Opper, A. K., Ostapenko, T., Reimer, P. E., Reinhold, J., Roche, J., Rock, S. E., Schulte, E., Segbefia, E., Smith, C., Smith, G. R., Stoler, P., Tadevosyan, V., Tang, L., Ungaro, M., Uzzle, A., Vidakovic, S., Villano, A., Vulcan, W. F., Wang, M., Warren, G., Wesselmann, F., Wojtsekhowski, B., Wood, S. A., Xu, C., Yuan, L., Zheng, X., and Zhu, H.
Subjects: High Energy Physics - Phenomenology
Abstract: Cross sections for semi-inclusive electroproduction of charged pions ($\pi^{\pm}$) from both proton and deuteron targets were measured for $0.2
Published: 2007
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133. Quasifree Lambda, Sigma^0, and Sigma^- electroproduction from 1,2H, 3,4He, and carbon

Author: Dohrmann, F., Ahmidouch, A., Armstrong, C. S., Arrington, J., Asaturyan, R., Avery, S., Bailey, K., Bitao, H., Breuer, H., Brown, D. S., Carlini, R., Cha, J., Chant, N., Christy, E., Cochran, A., Cole, L., Crowder, J., Danagoulian, S., Elaasar, M., Ent, R., Fenker, H., Fujii, Y., Gan, L., Garrow, K., Geesaman, D. F., Gueye, P., Hafidi, K., Hinton, W., Juengst, H., Keppel, C., Liang, Y., Liu, J. H., Lung, A., Mack, D., Markowitz, P., Mitchell, J., Miyoshi, T., Mkrtchyan, H., Mtingwa, S. K., Mueller, B., Niculescu, G., Niculescu, I., Potterveld, D., Raue, B. A., Reimer, P. E., Reinhold, J., Roche, J., Sarsour, M., Sato, Y., Segel, R. E., Semenov, A., Stepanyan, S., Tadevosyan, V., Tajima, S., Tang, L., Uzzle, A., Wood, S., Yamaguchi, H., Yan, C., Yuan, L., Zeidman, B., Zeier, M., and Zihlmann, B.
Subjects: Nuclear Experiment
Abstract: Kaon electroproduction from light nuclei and hydrogen, using 1H, 2H, 3He, 4He, and Carbon targets has been measured at Jefferson Laboratory. The quasifree angular distributions of Lambda and Sigma hyperons were determined at Q^2= 0.35(GeV/c)^2 and W= 1.91GeV. Electroproduction on hydrogen was measured at the same kinematics for reference., Comment: 34 pages, 9 figures v2:minor grammatical changes, correcting typos
Published: 2007
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134. Voltage Induced Hidden Symmetry and Photon Entanglement Generation in a Single, Site-Selected Quantum Dot

Author: Reimer, Michael E., Korkusinski, Marek, Lefebvre, Jacques, Lapointe, Jean, Poole, Philip J., Aers, Geof C., Dalacu, Dan, McKinnon, W. Ross, Frederick, Simon, Hawrylak, Pawel, and Williams, Robin L.
Subjects: Quantum Physics
Abstract: Present proposals for the realisation of entangled photon pair sources using the radiative decay of the biexciton in semiconductor quantum dots are limited by the need to enforce degeneracy of the two intermediate, single exciton states. We show how this requirement is lifted if the biexciton binding energy can be tuned to zero and we demonstrate this unbinding of the biexciton in a single, pre-positioned InAs quantum dot subject to a lateral electric field. Full Configuration-Interaction calculations are presented that reveal how the biexciton is unbound through manipulation of the electron-hole Coulomb interaction and the consequent introduction of Hidden Symmetry., Comment: 4 pages, 4 figures submitted to Physical Review Letters
Published: 2007

135. High Resolution Spectroscopy of 12B_Lambda by Electroproduction

Author: Iodice, M., Cusanno, F., Acha, A., Ambrozewicz, P., Aniol, K. A., Baturin, P., Bertin, P. Y., Benaoum, H., Blomqvist, K. I., Boeglin, W. U., Breuer, H., Brindza, P., Bydzovsky, P., Camsonne, A., Chang, C. C., Chen, J. -P., Choi, Seonho, Chudakov, E. A., Cisbani, E., Colilli, S., Coman, L., Craver, B. J., DeCataldo, G., deJager, C. W., DeLeo, R., Deur, A. P., Ferdi, C., Feuerbach, R. J., Folts, E., Fratoni, R., Frullani, S., Garibaldi, F., Gayou, O., Giulani, F., Gomez, J., Gricia, M., Hansen, J. O., Hayes, D., Higinbotham, D. W., Holmstrom, T. K., Hyde, C. E., Ibrahim, H. F., Jiang, X., Kaufman, L. J., Kino, K., Kross, B., Lagamba, L., LeRose, J. J., Lindgren, R. A., Lucentini, M., Margaziotis, D. J., Markowitz, P., Marrone, S., Meziani, Z. E., McCormick, K., Michaels, R. W., Millener, D. J., Miyoshi, T., Moffit, B., Monaghan, P. A., Moteabbed, M., MunozCamacho, C., Nanda, S., Nappi, E., Nelyubin, V. V., Norum, B. E., Okasyasu, Y., Paschke, K. D., Perdrisat, C. F., Piasetzky, E., Punjabi, V. A., Qiang, Y., Raue, B., Reimer, P. E., Reinhold, J., Reitz, B., Roche, R. E., Rodriguez, V. M., Saha, A., Santavenere, F., Sarty, A. J., Segal, J., Shahinyan, A., Singh, J., Sirca, S., Snyder, R., Solvignon, P. H., Sotona, M., Subedi, R., Sulkosky, V. A., Suzuki, T., Ueno, H., Ulmer, P. E., Urciuoli, G. M., Veneroni, P., Voutier, E., Wojtsekhowski, B. B., Zheng, X., and Zorn, C.
Subjects: Nuclear Experiment
Abstract: An experiment measuring electroproduction of hypernuclei has been performed in Hall A at Jefferson Lab on a $^{12}$C target. In order to increase counting rates and provide unambiguous kaon identification two superconducting septum magnets and a Ring Imaging CHerenkov detector (RICH) were added to the Hall A standard equipment. An unprecedented energy resolution of less than 700 keV FWHM has been achieved. Thus, the observed \lam{12}{B} spectrum shows for the first time identifiable strength in the core-excited region between the ground-state {\it s}-wave $\Lambda$ peak and the 11 MeV {\it p}-wave $\Lambda$ peak., Comment: Paper submitted to Physical Review Letters
Published: 2007
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136. Exploring the Partonic Structure of Hadrons through the Drell-Yan Process

Author: Reimer, Paul E.
Subjects: Nuclear Experiment
Abstract: The Drell-Yan process is a standard tool for probing the partonic structure of hadrons. Since the process proceeds through a quark-antiquark annihilation, Drell-Yan scattering possesses a unique ability to selectively probe sea distributions. This review examines the application of Drell-Yan scattering to elucidating the flavor asymmetry of the nucleon's sea and nuclear modifications to the sea quark distributions in unpolarized scattering. Polarized beams and targets add an exciting new dimension to Drell-Yan scattering. In particular, the two initial-state hadrons give Drell-Yan sensitivity to chirally-odd transversity distributions., Comment: 23 pages, 9 figures, to appear in J. Phys. G, resubmission corrects typographical errors
Published: 2007
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137. Angular dependence of recoil proton polarization in high-energy \gamma d \to p n

Author: Jiang, X., Arrington, J., Benmokhtar, F., Camsonne, A., Chen, J. P., Choi, S., Chudakov, E., Cusanno, F., Deur, A., Dutta, D., Garibaldi, F., Gaskell, D., Gayou, O., Gilman, R., Glashauser, C., Hamilton, D., Hansen, O., Higinbotham, D. W., Holt, R. J., de Jager, C. W., Jones, M. K., Kaufman, L. J., Kinney, E. R., Kramer, K., Lagamba, L., de Leo, R., Lerose, J., Lhuillier, D., Lindgren, R., Liyanage, N., McCormick, K., Meziani, Z. -E., Michaels, R., Moffit, B., Monaghan, P., Nanda, S., Paschke, K. D., Perdrisat, C. F., Punjabi, V., Qattan, I. A., Ransome, R. D., Reimer, P. E., Reitz, B., Saha, A., Schulte, E. C., Sheyor, R., Slifer, K., Solvignon, P., Sulkosky, V., Urciuoli, G. M., Voutier, E., Wang, K., Wijesooriya, K., Wojtsekhowski, B., and Zhu, L.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: We measured the angular dependence of the three recoil proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily.. Transverse polarizations are not well described, but suggest isovector dominance., Comment: 5 pages, 1 figure, submitted to Physical Review Letters
Published: 2007
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138. A Search for Sigma^0_5, N^0_5 and Theta^++ Pentaquark States

Author: Qiang, Y., Annand, J., Arrington, J., Azimov, Ya. I., Bertozzi, W., Cates, G., Chen, J. P., Choi, Seonho, Chudakov, E., Cusanno, F., de Jager, C. W., Epstein, M., Feuerbach, R. J., Garibaldi, F., Gayou, O., Gilman, R., Gomez, J., Hamilton, D. J., Hansen, J. -O., Higinbotham, D. W., Holmstrom, T., Iodice, M., Jiang, X., Jones, M., LeRose, J., Lindgren, R., Liyanage, N., Margaziotis, D. J., Markowitz, P., Mamyan, V., Michaels, R., Meziani, Z. -E., Monaghan, P., Munoz-Camacho, C., Nelyubin, V., Paschke, K., Piasetzky, E., Rachek, I., Reimer, P. E., Reinhold, J., Reitz, B., Roche, R., Saha, A., Sarty, A., Schulte, E., Shahinyan, A., Sheyor, R., Singh, J., Strakovsky, I. I., Subedi, R., Suleiman, R., Sulkovsky, V., Wojtsekhowski, B., and Zheng, X.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: A high-resolution (sigma_instr. = 1.5 MeV) search for narrow states (Gamma < 10 MeV) with masses of M_x approx 1500-1850 MeV in ep -> e'K^+ X, e'K^- X and e' pi^+ X electroproduction at small angles and low Q^2 was performed. These states would be candidate partner states of the reported Theta^+(1540) pentaquark. No statistically significant signal was observed in any of the channels at 90% C.L. Upper limits on forward production were determined to be between 0.7% and 4.2% of the Lambda(1520) production cross section, depending on the channel and the assumed mass and width of the state., Comment: 5 pages, 5 figures, to appear in Phys. Rev. C, update with responses to referee suggestions
Published: 2006
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139. Measurement of Angular Distributions of Drell-Yan Dimuons in p + d Interaction at 800 GeV/c

Author: Zhu, L. Y., Peng, J. C., Reimer, P. E., Awes, T. C., Brooks, M. L., and Brown, C. N.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Experiment
Abstract: We report a measurement of the angular distributions of Drell-Yan dimuons produced using an 800 GeV/c proton beam on a deuterium target. The muon angular distributions in polar angle $\theta$ and azimuthal angle $\phi$ have been measured over the kinematic range $4.5 < m_{\mu \mu} < 15$ GeV/c$^2$, $0 < p_T < 4 $ GeV/c, and $0 < x_F < 0.8$. No significant cos$2\phi$ dependence is found in these proton-induced Drell-Yan data, in contrast to the situation for pion-induced Drell-Yan. The data are compared with expectations from models which attribute the cos$2\phi$ distribution to a QCD vacuum effect or to the presence of the transverse-momentum-dependent Boer-Mulders structure function $h_1^\perp$. Constraints on the magnitude of the sea-quark $h_1^\perp$ structure functions are obtained., Comment: 4 pages, 3 figures
Published: 2006
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140. The pion parton distribution function in the valence region

Author: Wijesooriya, K., Reimer, P. E., and Holt, R. J.
Subjects: Nuclear Experiment
Abstract: The parton distribution function of the pion in the valence region is extracted in a next-to-leading order analysis from Fermilab E-615 pionic Drell-Yan data. The effects of the parameterization of the pion's valence distributions are examined. Modern nucleon parton distributions and nuclear corrections were used and possible effects from higher twist contributions were considered in the analysis. In the next-to-leading order analysis, the high-$x$ dependence of the pion structure function differs from that of the leading order analysis, but not enough to agree with the expectations of pQCD and Dyson-Schwinger calculations., Comment: 5 pages, 4 figures, submitted to Phys. Rev. C
Published: 2005
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141. Publisher Correction: The asymmetry of antimatter in the proton

Author: Dove, J., Kerns, B., McClellan, R. E., Miyasaka, S., Morton, D. H., Nagai, K., Prasad, S., Sanftl, F., Scott, M. B. C., Tadepalli, A. S., Aidala, C. A., Arrington, J., Ayuso, C., Barker, C. L., Brown, C. N., Chang, W. C., Chen, A., Christian, D. C., Dannowitz, B. P., Daugherity, M., Diefenthaler, M., El Fassi, L., Geesaman, D. F., Gilman, R., Goto, Y., Guo, L., Guo, R., Hague, T. J., Holt, R. J., Isenhower, D., Kinney, E. R., Kitts, N., Klein, A., Kleinjan, D. W., Kudo, Y., Leung, C., Lin, P.-J., Liu, K., Liu, M. X., Lorenzon, W., Makins, N. C. R., de Medeiros, M. Mesquita, McGaughey, P. L., Miyachi, Y., Mooney, I., Nakahara, K., Nakano, K., Nara, S., Peng, J.-C., Puckett, A. J., Ramson, B. J., Reimer, P. E., Rubin, J. G., Sawada, S., Sawada, T., Shibata, T.-A., Su, D., Teo, M., Tice, B. G., Towell, R. S., Uemura, S., Watson, S., Wang, S. G., Wickes, A. B., Wu, J., Xi, Z., and Ye, Z.
Published: 2022
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142. J/Psi Polarization in 800-GeV p-Cu Interactions

Author: Chang, T. H., Beddo, M. E., Brown, C. N., Carey, T. A., Cooper, W. E., Gagliardi, C. A., Garvey, G. T., Geesaman, D. F., Hawker, E. A., He, X. C., Isenhower, L. D., Kaplan, D. M., Kaufman, S. B., Koetke, D. D., Kyle, G. S., McGaughey, P. L., Lee, W. M., Leitch, M. J., Moss, J. M., Mueller, B. A., Papavassiliou, V., Peng, J. C., Petitt, G., Reimer, P. E., Sadler, M. E., Sondheim, W. E., Stankus, P. W., Towell, R. S., Tribble, R. E., Vasiliev, M. A., Webb, J. C., Willis, J. L., and Young, G. R.
Subjects: High Energy Physics - Experiment
Abstract: We present measurements of the polarization of the $ J/\psi $ produced in 800-GeV proton interactions with a copper target. Polarization of the $ J/\psi $ is sensitive to the $ c \bar{c} $ production and hadronization processes. A longitudinal polarization is observed at large $ x_{F} $, while at small $ x_{F} $ the state is produced essentially unpolarized or slightly transversely polarized. No significant variation of the polarization is observed versus $ p_{T} $., Comment: 4 pages, 3 figures
Published: 2003
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143. Absolute Drell-Yan Dimuon Cross Sections in 800 GeV/c pp and pd Collisions

Author: Collaboration, FNAL E866/NuSea, Webb, J. C., Awes, T. C., Brooks, M. L., Brown, C. N., Bush, J. D., Carey, T. A., Chang, T. H., Cooper, W. E., Gagliardi, C. A., Garvey, G. T., Geesaman, D. F., Hawker, E. A., He, X. C., Isenhower, L. D., Kaplan, D. M., Kaufman, S. B., Koetke, D. D., Lee, D. M., Lee, W. M., Leitch, M. J., Makins, N., McGaughey, P. L., Moss, J. M., Mueller, B. A., Nord, P. M., Papavassiliou, V., Park, B. K., Peng, J. C., Petitt, G., Reimer, P. E., Sadler, M. E., Sondheim, W. E., Stankus, P. W., Thompson, T. N., Towell, R. S., Tribble, R. E., Vasiliev, M. A., Willis, J. L., Wise, D. K., and Young, G. R.
Subjects: High Energy Physics - Experiment
Abstract: The Fermilab E866/NuSea Collaboration has measured the Drell-Yan dimuon cross sections in 800 GeV/$c$ $pp$ and $pd$ collisions. This represents the first measurement of the Drell-Yan cross section in $pp$ collisions over a broad kinematic region and the most extensive study to date of the Drell-Yan cross section in $pd$ collisions. The results indicate that recent global parton distribution fits provide a good description of the light antiquark sea in the nucleon over the Bjorken-$x$ range $0.03 \lesssim x < 0.15$, but overestimate the valence quark distributions as $x \to 1$., Comment: submitted to Phys. Rev. Lett
Published: 2003

144. Tapered InP nanowire arrays for efficient broadband high-speed single-photon detection

Author: Gibson, Sandra J., van Kasteren, Brad, Tekcan, Burak, Cui, Yingchao, van Dam, Dick, Haverkort, Jos E. M., Bakkers, Erik P. A. M., and Reimer, Michael E.
Published: 2019
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145. Observation of Polarization in Bottomonium Production at sqrt(s)=38.8 GeV

Author: Brown, C. N., Awes, T. C., Beddo, M. E., Brooks, M. L., Bush, J. D., Carey, T. A., Chang, T. H., Cooper, W. E., Gagliardi, C. A., Garvey, G. T., Geesaman, D. F., Hawker, E. A., He, X. C., Isenhower, L. D., Kaplan, D. M., Kaufman, S. B., Koetke, D. D., Kyle, G., Lee, W. M., Leitch, M. J., Makins, N., McGaughey, P. L., Moss, J. M., Mueller, B. A., Nord, P. M., Papavassiliou, V., Park, B. K., Peng, J. C., Petitt, G., Reimer, P. E., Sadler, M. E., Stankus, P. W., Towell, R. S., Tribble, R. E., Vasiliev, M. A., Webb, J. C., and Young, G. R.
Subjects: High Energy Physics - Experiment
Abstract: We present a measurement of the polarization observed for bottomonium states produced in p-Cu collisions at sqrt(s)=38.8 GeV. The angular distribution of the decay dimuons of the Upsilon(1S) state show no polarization at small xF and pT but significant positive transverse production polarization for either pT > 1.8 GeV/c or for xF > 0.35. The Upsilon(2S+3S) unresolved states show a large transverse production polarization at all values of xF and pT measured. These observations are compared with an NRQCD calculation that predicts a transverse polarization in bottomonium production arising from quark-antiquark fusion and gluon-gluon fusion diagrams., Comment: 4 pages, 4 figures
Published: 2000
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146. Sturcture of the Goldstone Bosons

Author: Holt, Roy J. and Reimer, Paul E.
Subjects: Nuclear Experiment
Abstract: The feasibility of measuring the pion and kaon structure functions has been investigated. A high luminosity electron-proton collider would make these measurements feasible. Also, it appears feasible to measure these structure functions in a nuclear medium. Simulations using the RAPGAP Monte Carlo of a possible pion structure function measurement are presented., Comment: To appear in the proceedings of the Second Workshop on Physics with an Electron Polarized Light-Ion Collider, 14-16 Sept 2000, Cambridge, Ma 6 pages, 5 figures, latex
Published: 2000
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147. Measurement of Differences Between J/Psi and Psi' Suppression in p-A Collisions

Author: Leitch, M. J., Lee, W. M., Beddo, M. E., Brown, C. N., Carey, T. A., Chang, T. H., Cooper, W. E., Gagliardi, C. A., Garvey, G. T., Geesaman, D. F., Hawker, E. A., He, X. C., Isenhower, L. D., Kaplan, D. M., Kaufman, S. B., Koetke, D. D., McGaughey, P. L., Moss, J. M., Mueller, B. A., Papavassiliou, V., Peng, J. C., Petitt, G., Reimer, P. E., Sadler, M. E., Sondheim, W. E., Stankus, P. W., Towell, R. S., Tribble, R. E., Vasiliev, M. A., Webb, J. C., Willis, J. L., and Young, G. R.
Subjects: Nuclear Experiment
Abstract: Measurements of the suppression of the yield per nucleon of J/Psi and Psi' production for 800 GeV/c protons incident on heavy relative to light nuclear targets have been made with very broad coverage in xF and pT. The observed suppression is smallest at xF values of 0.25 and below and increases at larger values of xF. It is also strongest at small pT. Substantial differences between the Psi' and J/Psi are observed for the first time in p-A collisions. The suppression for the Psi' is stronger than that for the J/Psi for xF near zero, but becomes comparable to that for the J/Psi for xF > 0.6., Comment: 5 pages, 4 figures, accepted for publication by PRL
Published: 1999
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148. Parton energy loss limits and shadowing in Drell-Yan dimuon production

Author: Vasiliev, M. A., Beddo, M. E., Brown, C. N., Carey, T. A., Chang, T. H., Cooper, W. E., Gagliardi, C. A., Garvey, G. T., Geesaman, D. F., Hawker, E. A., He, X. C., Isenhower, L. D., Kaplan, D. M., Kaufman, S. B., Koetke, D. D., Lee, W. M., Leitch, M. J., McGaughey, P. L., Moss, J. M., Mueller, B. A., Papavassiliou, V., Peng, J. C., Petitt, G., Reimer, P. E., Sadler, M. E., Sondheim, W. E., Stankus, P. W., Towell, R. S., Tribble, R. E., Webb, J. C., Willis, J. L., and Young, G. R.
Subjects: High Energy Physics - Experiment
Abstract: A precise measurement of the ratios of the Drell-Yan cross section per nucleon for an 800 GeV/c proton beam incident on Be, Fe and W targets is reported. The behavior of the Drell-Yan ratios at small target parton momentum fraction is well described by an existing fit to the shadowing observed in deep-inelastic scattering. The cross section ratios as a function of the incident parton momentum fraction set tight limits on the energy loss of quarks passing through a cold nucleus.
Published: 1999
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149. dbar/ubar Asymmetry and the Origin of the Nucleon Sea

Author: Peng, J. C., Garvey, G. T., Awes, T. C., Beddo, M. E., Brooks, M. L., Brown, C. N., Bush, J. D., Carey, T. A., Chang, T. H., Cooper, W. E., Gagliardi, C. A., Geesaman, D. F., Hawker, E. A., He, X. C., Isenhower, L. D., Kaufman, S. B., Kaplan, D. M., Kirk, P. N., Koetke, D. D., Kyle, G., Lee, D. M., Lee, W. M., Leitch, M. J., Makins, N., McGaughey, P. L., Moss, J. M., Mueller, B. A., Nord, P. M., Park, B. K., Papavassiliou, V., Petitt, G., Reimer, P. E., Sadler, M. E., Selden, J., Stankus, P. W., Sondheim, W. E., Thompson, T. N., Towell, R. S., Tribble, R. E., Vasiliev, M. A., Wang, Y. C., Wang, Z. F., Webb, J. C., Willis, J. L., Wise, D. K., and Young, G. R.
Subjects: High Energy Physics - Phenomenology
Abstract: The Drell-Yan cross section ratios, $\sigma(p+d)/\sigma(p+p)$, measured in Fermilab E866, have led to the first determination of $\bar d(x) / \bar u(x)$, $\bar d(x) - \bar u(x)$, and the integral of $\bar d(x) - \bar u(x)$ for the proton over the range $0.02 \le x \le 0.345$. The E866 results are compared with predictions based on parton distribution functions and various theoretical models. The relationship between the E866 results and the NMC measurement of the Gottfried integral is discussed. The agreement between the E866 results and models employing virtual mesons indicates these non-perturbative processes play an important role in the origin of the $\bar d$, $\bar u$ asymmetry in the nucleon sea., Comment: 5 pages, 3 figures, ReVTeX
Published: 1998
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150. Measurement of the Light Antiquark Flavor Asymmetry in the Nucleon Sea

Author: Hawker, E. A., Awes, T. C., Beddo, M. E., Brown, C. N., Bush, J. D., Carey, T. A., Chang, T. H., Cooper, W. E., Gagliardi, C. A., Garvey, G. T., Geesaman, D. F., He, X. C., Isenhower, L. D., Kaufman, S. B., Kaplan, D. M., Kirk, P. N., Koetke, D. D., Kyle, G., Lee, D. M., Lee, W. M., Leitch, M. J., Makins, N., McGaughey, P. L., Moss, J. M., Mueller, B. A., Nord, P. M., Park, B. K., Papavassiliou, V., Peng, J. C., Petitt, G., Reimer, P. E., Sadler, M. E., Selden, J., Stankus, P. W., Sondheim, W. E., Thompson, T. N., Towell, R. S., Tribble, R. E., Vasiliev, M. A., Wang, Y. C., Wang, Z. F., Webb, J. C., Willis, J. L., Wise, D. K., and Young, G. R.
Subjects: High Energy Physics - Experiment
Abstract: A precise measurement of the ratio of Drell-Yan yields from an 800 GeV/c proton beam incident on hydrogen and deuterium targets is reported. Over 140,000 Drell-Yan muon pairs with dimuon mass M_{mu+ mu-} >= 4.5 GeV/c^2 were recorded. From these data, the ratio of anti-down (dbar) to anti-up (ubar) quark distributions in the proton sea is determined over a wide range in Bjorken-x. A strong x dependence is observed in the ratio dbar/ubar, showing substantial enhancement of dbar with respect to ubar for x<0.2. This result is in fair agreement with recent parton distribution parameterizations of the sea. For x>0.2, the observed dbar/ubar ratio is much nearer unity than given by the parameterizations., Comment: REVTeX, to be published in Phys. Rev. Lett
Published: 1998
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