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16 results on '"Garcon, M."'

1. Determination of the proton spin structure functions for 0.05<Q2<5GeV2 using CLAS

Author

Fersch, R. G., Guler, N., Bosted, P., Deur, A., Griffioen, K., Keith, C., Kuhn, S. E., Minehart, R., Prok, Y., Adhikari, K. P., Adhikari, S., Akbar, Z., Amaryan, M. J., Pereira, S. Anefalos, Asryan, G., Avakian, H., Ball, J., Balossino, I., Baltzell, N. A., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Briscoe, W. J., Brooks, W. K., Bultmann, S., Burkert, V. D., Cao, Frank Thanh, Carman, D. S., Careccia, S., Celentano, A., Chandavar, S., Charles, G., Chetry, T., Ciullo, G., Clark, L., Colaneri, L., Cole, P. L., Compton, N., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Djalali, C., Dodge, G. E., Dupre, R., Egiyan, H., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fanchini, E., Fedotov, G., Filippi, A., Fleming, J. A., Forest, T. A., Garcon, M., Gavalian, G., Ghandilyan, Y., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Gleason, C., Golovatch, E., Gothe, R. W., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Heddle, D., Hicks, K., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Joo, K., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Lagerquist, V. G., Lanza, L., Lenisa, P., Livingston, K., Lu, H. Y., McKinnon, B., Meyer, C. A., Mirazita, M., Mokeev, V., Montgomery, R. A., Movsisyan, A., Camacho, C. Munoz, Murdoch, G., Nadel-Turonski, P., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Phelps, W., Pierce, J., Pisano, S., Pogorelko, O., Price, J. W., Protopopescu, D., Raue, B. A., Ripani, M., Riser, D., Rizzo, A., Rosner, G., Rossi, P., Roy, P., Sabatie, F., Salgado, C., Schumacher, R. A., Sharabian, Y. G., Simonyan, A., Skorodumina, Iu., Smith, G. D., Sokhan, D., Sparveris, N., Stankovic, I., Stepanyan, S., Strakovsky, I. I., Strauch, S., Taiuti, M., Tian, Ye, Torayev, B., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D. P., Wei, X., Weinstein, L. B., Zachariou, N., Zhang, J., and Collaboration, C. L. A. S.

Subjects
DEEP-INELASTIC-SCATTERING, HEARN SUM-RULE, ELECTRON-SCATTERING, QUANTUM CHROMODYNAMICS, POWER CORRECTIONS, FLAVOR DECOMPOSITION, PARTON DISTRIBUTIONS, QUARK-HADRON DUALITY, High Energy Physics::Experiment, PRECISION-MEASUREMENT, Nuclear Experiment, STRUCTURE FUNCTIONS G(1)(P)
Abstract

We present the results of our final analysis of the full data set of gp1(Q2), the spin structure function of the proton, collected using CLAS at Jefferson Laboratory in 2000–2001. Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.7 GeV were scattered from proton targets (15NH3 dynamically polarized along the beam direction) and detected with CLAS. From the measured double spin asymmetries, we extracted virtual photon asymmetries Ap1 and Ap2 and spin structure functions gp1 and gp2 over a wide kinematic range (0.05 GeV2

Published
2017

2. Semi-Inclusive $��_0$ target and beam-target asymmetries from 6 GeV electron scattering with CLAS

Author

Jawalkar, S., Koirala, S., Avakian, H., Bosted, P., Griffioen, K. A., Keith, C., Kuhn, S. E., Adhikari, K. P., Adhikari, S., Adikaram, D., Akbar, Z., Amaryan, M. J., Pereira, S. Anefalos, Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brock, J., Brooks, W. K., Bultmann, S., Burkert, V. D., Cao, Frank Thanh, Carlin, C., Carman, D. S., Celentano, A., Charles, G., Chetry, T., Ciullo, G., Clark, L., Colaneri, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Defurne, M., Deur, A., Djalali, C., Ddoge, G., Dupre, R., Egiyan, H., Alaoui, A. El, Fassi, L. El, Elouadrhiri, L., Eugenio, P., Fedotov, G., Fegan, S., Fersch, R., Filippi, A., Fleming, J. A., Forest, T. A., Fradi, A., Garcon, M., Ghandilyan, Y., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Gleason, C., Gohn, W., Golovatch, E., Gothe, R. W., Guidal, M., Guler, N., Guo, L., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Heddle, D., Hicks, K., Hollis, G., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jiang, H., Joo, K., Joosten, S., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Kuleshov, S. V., Lanza, L., Lenisa, P., Livingston, K., Lu, H. Y., MacGregor, I . J . D., Markov, N., Mayer, M., McCracken, M. E., McKinnon, B., Meyer, C. A., Mineeva, T., Mirazita, M., Mokeev, V., Montgomery, R. A., Movsisyan, A, Camacho, C. Munoz, Nadel-Turonski, P., Net, L. A., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Paremuzyan, R., Park, K., Pasyuk, E., Phelps, E., Phelps, W., Pierce, J., Pisano, S., Pogorelko, O., Price, J. W., Prok, Y., Protopopescu, D., Raue, B. A., Ripani, M., Riser, D., Rizzo, A., Rosner, G., Rossi, P., Sabatie, F., Salgado, C., Schumacher, R. A., Seder, E., Sharabian, Y. G., Simonyan, A., Skorodumina, Iu., Smith, G. D., Sober, D. I., Sokhan, D., Sparveris, N., Stankovic, I., Strauch, S., Taiuti, M., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D. P., Wei, X., Weinstein, L. B., Wood, M. H., Zachariou, N., Zhang, J., and Zhao, Z. W.

Subjects
High Energy Physics - Phenomenology (hep-ph), Physics::Accelerator Physics, FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

We present precision measurements of the target and beam-target spin asymmetries from neutral pion electroproduction in deep-inelastic scattering (DIS) using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. We scattered 6-GeV, longitudinally polarized electrons off longitudinally polarized protons in a cryogenic $^{14}$NH$_3$ target, and extracted double and single target spin asymmetries for $ep\rightarrow e^\prime��^0X$ in multidimensional bins in four-momentum transfer ($1.0, 18 preprint pages, 3 figures

Published
2017
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3. Strangeness Suppression of q(q)over-bar Creation Observed in Exclusive Reactions

Author

Mestayer, M. D., Park, K., Adhikari, K. P., Aghasyan, M., Pereira, S. Anefalos, Ball, J., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Colaneri, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., Deur, A., Djalali, C., Doughty, D., Dupre, R., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fedotov, G., Fleming, J. A., Forest, T. A., Garillon, B., Garcon, M., Ghandilyan, Y., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Goetz, J. T., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guegan, B., Watts, D. P., and Zachariou, Nicholas

Subjects
HIGH-ENERGY, VERTICES, E&E ANNIHILATION, SEA, QUARK SUPPRESSION, FLAVOR ASYMMETRY, Nuclear Theory, High Energy Physics::Phenomenology, SCATTERING, High Energy Physics::Experiment, PARTICLE-PRODUCTION, Nuclear Experiment, FLUX-TUBE MODEL
Abstract

We measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: AK(+), p pi(0), and n pi(+), with the CLAS detector at Jefferson Lab. Using a simplemodel of quark hadronization, we extract q (q) over bar creation probabilities for the first time in exclusive two-body production, in which only a single q (q) over bar pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to nonstrange pairs, similar to that seen in high-energy production.

Published
2014

4. Exclusive π0 electroproduction at W>2 GeV with CLAS

Author

Bedlinskiy, I., Kubarovsky, V., Niccolai, S., Stoler, P., Adhikari, K. P., Anderson, M. D., Pereira, S. Anefalos, Avakian, H., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Biselli, A. S., Boiarinov, S., Bono, J., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Colaneri, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Doughty, D., Dupre, R., Egiyan, H., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fedotov, G., Fegan, S., Fleming, J. A., Forest, T. A., Garillon, B., Garcon, M., Gavalian, G., Gevorgyan, N., Ghandilyan, Y., Watts, D., and Zana, L.

Subjects
TRANSVERSITY, PARTON DISTRIBUTIONS, High Energy Physics::Experiment, Nuclear Experiment, PION ELECTROPRODUCTION, MESONS, SYSTEM
Abstract

Exclusive neutral-pion electroproduction (ep→e′p′π0) was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections d4σ/dtdQ2dxBdϕπ and structure functions σT+εσL,σTT, and σLT as functions of t were obtained over a wide range of Q2 and xB. The data are compared with Regge and handbag theoretical calculations. Analyses in both frameworks find that a large dominance of transverse processes is necessary to explain the experimental results. For the Regge analysis it is found that the inclusion of vector meson rescattering processes is necessary to bring the magnitude of the calculated and measured structure functions into rough agreement. In the handbag framework, there are two independent calculations, both of which appear to roughly explain the magnitude of the structure functions in terms of transversity generalized parton distributions.

Published
2014

5. Data analysis techniques, differential cross sections, and spin density matrix elements for the reaction gamma p -> phi p

Author

Dey, B., Meyer, C. A., Bellis, M., Williams, M., Adhikari, K. P., Adikaram, D., Aghasyan, M., Amaryan, M. J., Anderson, M. D., Pereira, S. Anefalos, Ball, J., Baltzell, N. A., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Bono, J., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Colaneri, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Doughty, D., Dugger, M., Dupre, R., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Fedotov, G., Fegan, S., Fleming, J. A., Garcon, M., Gevorgyan, N., Glazier, D. I., Lu, H., Smith, E. S., Watts, D. P., and Zhang, J.

Subjects
BREMSSTRAHLUNG, LARGE MOMENTUM-TRANSFER, MESON PHOTOPRODUCTION, SCATTERING, High Energy Physics::Experiment, WAVE INTERFERENCE, ELASTIC PHOTOPRODUCTION, HYDROGEN, VECTOR-MESONS, ENERGY PHOTOPRODUCTION, THRESHOLD
Abstract

High-statistics measurements of differential cross sections and spin density matrix elements for the reaction gamma p -> phi p have been made using the CLAS detector at Jefferson Lab. We cover center-of-mass energies (v s) from 1.97 to 2.84 GeV, with an extensive coverage in the phi production angle. The high statistics of the data sample made it necessary to carefully account for the interplay between the f natural lineshape and effects of the detector resolution, that are found to be comparable in magnitude. We study both the charged-(phi -> K+ K-) and neutral( phi ->(KsKL0)-K-0) K (K) over bar decay modes of the phi Further, for the charged mode, we differentiate between the cases where the final K-track is directly detected or its momentum reconstructed as the total missing momentum in the event. The two charged-mode topologies and the neutral-mode have different resolutions and are calibrated against each other. Extensive usage is made of kinematic fitting to improve the reconstructed f mass resolution. Our final results are reported in 10- and mostly 30-MeV-wide root s bins for the charged-and the neutral-modes, respectively. Possible effects from K+Lambda* channels with pK (K) over bar final states are discussed. These present results constitute the most precise and extensive phi photoproduction measurements to date and in conjunction with the omega photoproduction results recently published by CLAS, will greatly improve our understanding of low energy vector meson photoproduction.

Published
2014

6. Exclusive neutral pion electroproduction in the deeply virtual regime

Author

Fuchey, E., Camsonne, A., Munoz Camacho, C., Mazouz, M., Gavalian, G., Kuchina, E., Amarian, M., A. Aniol, K., Beaumel, M., Benaoum, H., Bertin, P.Y., Brossard, M., Canan, M., Chen, J.-P., Chudakov, E., Craver, B., Cusanno, F., De Jager, C.W., Deur, A., Ferdi, C., Feuerbach, R., Fieschi, J.-M., Frullani, S., Garcon, M., Garibaldi, F., Gayou, O., Gilman, R., Gomez, J., Gueye, P., Guichon, P.A.M., Guillon, B., Hansen, O., Hayes, D., Higinbotham, D.W., Holmstrom, T., Hyde, C. E., Ibrahim, H., Igarashi, R., Itard, F., Jiang, X., Jo, H.S., Kaufman, L.J., Kelleher, A., Kolarkar, A., Kumbartzki, G., Laveissiere, G., LeRose, J.J., Lindgren, R., Liyanage, N., Lu, H.-J., Margaziotis, D.J., Meziani, Z.-E., McCormick, K., Michaels, R., Michel, B., Moffit, B., Monaghan, P., Nanda, S., Nelyubin, V., Potokar, M., Qiang, Y., Ransome, R.D., Réal, J.S., Reitz, B., Roblin, Y., Roche, J., Sabatie, F., Saha, A., Sirca, S., Slifer, K., Solvignon, P., Subedi, R., Sulkosky, V., Ulmer, P.E., Voutier, E., Wang, K., Weinstein, L.B., Wojtsekhowski, B., Zheng, X., Zhu, L., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), DVCS, HALL A, Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Momentum transfer, FOS: Physical sciences, Elementary particle, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Inelastic scattering, Deep inelastic scattering, 01 natural sciences, Nuclear physics, Pion, 0103 physical sciences, High Energy Physics::Experiment, Tensor, Nuclear Experiment (nucl-ex), Nuclear Experiment, 010306 general physics, Boson
Abstract

We present measurements of the ep->ep pi^0 cross section extracted at two values of four-momentum transfer Q^2=1.9 GeV^2 and Q^2=2.3 GeV^2 at Jefferson Lab Hall A. The kinematic range allows to study the evolution of the extracted hadronic tensor as a function of Q^2 and W. Results will be confronted with Regge inspired calculations and GPD predictions. An intepretation of our data within the framework of semi-inclusive deep inelastic scattering has also been attempted.

Published
2011

7. Precise measurement of the neutron magnetic form factor G(M)n in the few-GeV2 region

Author

Lachniet, J., Afanasev, A., Arenhoevel, H., Brooks, W. K., Gilfoyle, G. P., Higinbotham, D., Jeschonnek, S., Quinn, B., Vineyard, M. F., Adams, G., Adhikari, K. P., Amaryan, M. J., Anghinolfi, M., Asavapibhop, B., Asryan, G., Avakian, H., Bagdasaryan, H., Baillie, N., Ball, J. P., Baltzell, N. A., Barrow, S., Batourine, V., Battaglieri, M., Beard, K., Bedlinskiy, I., Bektasoglu, M., Bellis, M., Benmouna, N., Berman, B. L., Biselli, A. S., Bonner, B. E., Bookwalter, C., Bouchigny, S., Boiarinov, S., Bradford, R., Branford, D., Briscoe, W. J., Bueltmann, S., Burkert, V. D., Calarco, J. R., Careccia, S. L., Carman, D. S., Casey, L., Cheng, L., Cole, P. L., Coleman, A., Collins, P., Cords, D., Corvisiero, P., Crabb, D., Crede, V., Cummings, J. P., Dale, D., Daniel, A., Dashyan, N., De Masi, R., De Vita, R., De Sanctis, E., Degtyarenko, P. V., Denizli, H., Dennis, L., Deur, A., Dhamija, S., Dharmawardane, K. V., Dhuga, K. S., Dickson, R., Djalali, C., Dodge, G. E., Doughty, D., Dragovitsch, P., Dugger, M., Dytman, S., Dzyubak, O. P., Egiyan, H., Egiyan, K. S., El Fassi, L., Elouadrhiri, L., Empl, A., Eugenio, P., Fatemi, R., Fedotov, G., Fersch, R., Feuerbach, R. J., Forest, T. A., Fradi, A., Gabrielyan, M. Y., Garcon, M., Gavalian, G., Gevorgyan, N., Giovanetti, K. L., Girod, F. X., Goetz, J. T., Gohn, W., Golovatch, E., Gothe, R. W., Graham, L., Griffioen, K. A., Guidal, M., Guillo, M., Guler, N., Guo, L., Gyurjyan, V., Hadjidakis, C., Hafidi, K., Hakobyan, H., Hanretty, C., Hardie, J., Hassall, N., Heddle, D., Hersman, F. W., Hicks, K., Hleiqawi, I., Holtrop, M., Hu, J., Huertas, M., Hyde-Wright, C. E., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Ito, M. M., Jenkins, D., Jo, H. S., Johnstone, J. R., Joo, K., Juengst, H. G., Kageya, T., Kalantarians, N., Keller, D., Kellie, J. D., Khandaker, M., Khetarpal, P., Kim, K. Y., Kim, K., Kim, W., Klein, A., Klein, F. J., Klusman, M., Konczykowski, P., Kossov, M., Kramer, L. H., Kubarovsky, V., Kuhn, J., Kuhn, S. E., Kuleshov, S. V., Kuznetsov, V., Laget, J. M., Langheinrich, J., Lawrence, D., Lima, A. C. S., Livingston, K., Lowry, M., Lu, H. Y., Lukashin, K., MacCormick, M., Malace, S., Manak, J. J., Markov, N., Mattione, P., McAleer, S., McCracken, M. E., McKinnon, B., McNabb, J. W. C., Mecking, B. A., Mestayer, M. D., Meyer, C. A., Mibe, T., Mikhailov, K., Mineeva, T., Minehart, R., Mirazita, M., Miskimen, R., Mokeev, V., Moreno, B., Moriya, K., Morrow, S. A., Moteabbed, M., Mueller, J., Munevar, E., Mutchler, G. S., Nadel-Turonski, P., Nasseripour, R., Niccolai, S., Niculescu, G., Niculescu, I., Niczyporuk, B. B., Niroula, M. R., Niyazov, R. A., Nozar, M., O'Rielly, G. V., Osipenko, M., Ostrovidov, A. I., Park, K., Park, S., Pasyuk, E., Paterson, C., Pereira, S. Anefalos, Philips, S. A., Pierce, J., Pivnyuk, N., Pocanic, D., Pogorelko, O., Polli, E., Popa, I., Pozdniakov, S., Preedom, B. M., Price, J. W., Prok, Y., Protopopescu, D., Qin, L. M., Raue, B. A., Riccardi, G., Ricco, G., Ripani, M., Ritchie, B. G., Rosner, G., Rossi, P., Rowntree, D., Rubin, P. D., Sabatie, F., Saini, M. S., Salamanca, J., Salgado, C., Sandorfi, A., Santoro, J. P., Sapunenko, V., Schott, D., Schumacher, R. A., Serov, V. S., Sharabian, Y. G., Sharov, D., Shaw, J., Shvedunov, N. V., Skabelin, A. V., Smith, E. S., Smith, L. C., Sober, D. I., Sokhan, D., Starostin, A., Stavinsky, A., Stepanyan, S., Stepanyan, S. S., Stokes, B. E., Stoler, P., Stopani, K. A., Strakovsky, I. I., Strauch, S., Suleiman, R., Taiuti, M., Taylor, S., Tedeschi, D. J., Thompson, R., Tkabladze, A., Tkachenko, S., Ungaro, M., Vlassov, A. V., Watts, D. P., Wei, X., Weinstein, L. B., Weygand, D. P., Williams, M., Wolin, E., Wood, M. H., Yegneswaran, A., Yun, J., Yurov, M., Zana, L., Zhang, J., Zhao, B., and Zhao, Z. W.

Subjects
High Energy Physics::Experiment, Nuclear Experiment
Abstract

The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q(2)=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.

Published
2008

8. Measurement of ep -> ep pi(0) beam spin asymmetries above the resonance region

Author

De Masi, R., Garcon, M., Zhao, B., Amaryan, M. J., Ambrozewicz, P., Anghinolfi, M., Asryan, G., Avakian, H., Bagdasaryan, H., Baillie, N., Ball, J., Ball, J. P., Baltzell, N. A., Batourine, V., Battaglieri, M., Bedlinskiy, I., Bellis, M., Benmouna, N., Berman, B. L., Bertin, P., Biselli, A. S., Blaszczyk, L., Bouchigny, S., Boiarinov, S., Bradford, R., Branford, D., Briscoe, W. J., Brooks, W. K., Bultmann, S., Burkert, V. D., Butuceanu, C., Calarco, J. R., Careccia, S. L., Carman, D. S., Casey, L., Chen, S., Cheng, L., Cole, P. L., Collins, P., Coltharp, P., Crabb, D., Crede, V., Dashyan, N., De Sanctis, E., De Vita, R., Degtyarenko, P. V., Deur, A., Dharmawardane, K. V., Dickson, R., and Watts, D. P.

Subjects
Nuclear and High Energy Physics, High Energy Physics::Experiment, Nuclear Experiment
Abstract

The beam spin asymmetry (BSA) in the exclusive reaction ep -> ep pi(0) was measured with the CEBAF 5.77 GeV polarized electron beam and Large Acceptance Spectrometer (CLAS). The x(B),Q(2),t, and phi dependences of the pi(0) BSA are presented in the deep inelastic regime. The asymmetries are fitted with a sin phi function and their amplitudes are extracted. Overall, they are of the order of 0.04-0.11 and roughly independent of t. This is the signature of a nonzero longitudinal-transverse interference. The implications concerning the applicability of a formalism based on generalized parton distributions, as well as the extension of a Regge formalism at high photon virtualities, are discussed.

Published
2008

9. Electroproduction of $\phi(1020)$ mesons at $1.4\leq Q^2\leq$ GeV$^2$ measured with the CLAS spectrometer

Author

Santoro, J. P., Smith, E. S., Garcon, M., Guidal, M., Laget, J. M., and Weiss, C.

Subjects
High Energy Physics::Experiment, Astrophysics::Cosmology and Extragalactic Astrophysics, Nuclear Experiment
Abstract

Electroproduction of exclusive $\phi$ vector mesons has been studied with the CLAS detector in the kinematical range $1.4\leq Q^2\leq 3.8$ GeV$^{2}$, $0.0\leq t^{\prime}\leq 3.6$ GeV$^{2}$, and $2.0\leq W\leq 3.0$ GeV. The scaling exponent for the total cross section as $1/(Q^2+M_{\phi}^2)^n$ was determined to be $n=2.49\pm 0.33$. The slope of the four-momentum transfer $t'$ distribution is $b_{\phi}=0.98 \pm 0.17$ GeV$^{-2}$. Under the assumption of s-channel helicity conservation (SCHC), we determine the ratio of longitudinal to transverse cross sections to be $R=0.86 \pm 0.24$. A 2-gluon exchange model is able to reproduce the main features of the data., Comment: Phys Rev C, 15 pages, 18 figures

Published
2008

10. Ratios of (15)N/(12)C and (4)He/(12)C inclusive electroproduction cross sections in the nucleon resonance region

Author

Bosted, Pe, Fersch, R, Adams, G, Amarian, M, Anefalos Pereira Sergio, Anghinolfi, Marco, Asryan, G, Avakian, H, Bagdasaryan, H, Baillie, N, Ball, Jp, Baltzell, Na, Barrow, S, Batourine, V, Battaglieri, Marco, Beard, K, Bedlinskiy, I, Bektasoglu, M, Bellis, M, Benmouna, N, Biselli, As, Bonner, Be, Bouchigny, S, Boiarinov, S, Bradford, R, Branford, D, Brooks, Wk, Ultmann, Sbr, Burkert, Vd, Butuceanu, C, Calarco, Jr, Careccia, Sl, Carman, Ds, Carnahan, B, Cazes, A, Chen, S, Cole, Pl, Collins, P, Coltharp, P, Cords, D, Corvisiero, Pietro, Crabb, D, Crannell, H, Crede, V, Cummings, Jp, De Masi, R, De Vita Raffaella, De Sanctis Enzo, Degtyarenko, Pv, Denizli, H, Dennis, L, Deur, A, Djalali, C, Dodge, Ge, Donnelly, J, Doughty, D, Dragovitsch, P, Dugger, M, Dharmawardane, Kv, Dytman, S, Dzyubak, Op, Egiyan, H, Egiyan, Ks, Elouadrhiri, L, Eugenio, P, Fatemi, R, Fedotov, G, Feuerbach, Rj, Forest, Ta, Fradi, A, Funsten, H, Garcon, M, Gavalian, G, Gilfoyle, Gp, Giovanetti, Kl, Girod, Fx, Goetz, Jt, Golovatch, E, Gothe, Rw, Griffioen, Ka, Guidal, M, Guillo, M, Guler, N, Guo, L, Gyurjyan, V, Hadjidakis, C, Hafidi, K, Hakobyan, Rs, Hardie, J, Heddle, D, Hersman, Fw, Hicks, K, Hleiqawi, I, Holtrop, M, Huertas, M, Hyde Wright CE, Ilieva, Y, Ireland, Dg, Ishkhanov, Bs, Isupov, El, Ito, Mm, Jenkins, D, Jo, Hs, Joo, K, Juengst, Hg, Kalantarians, N, Keith, C, Kellie, Jd, Khandaker, M, Kim, Ky, Kim, K, Kim, W, Klein, A, Klein, Fj, Klusman, M, Kossov, M, Kramer, Lh, Kubarovsky, V, Kuhn, J, Kuhn, Se, Kuleshov, Sv, Lachniet, J, Laget, Jm, Langheinrich, J, Lawrence, D, Li, J, Lima, Acs, Livingston, K, Lu, H, Lukashin, K, Maccormick, M, Markov, N, Mcaleer, S, Mckinnon, B, Mcnabb, Jwc, Mecking, Ba, Mestayer, Md, Meyer, Ca, Mibe, T, Mikhailov, K, Minehart, R, Mirazita, Marco, Miskimen, R, Mokeev, V, Morand, L, Morrow, Sa, Moteabbed, M, Mueller, J, Mutchler, Gs, Nadel Turonski, P, Nasseripour, R, Niccolai, S, Niculescu, G, Niculescu, I, Niczyporuk, Bb, Niroula, Mr, Niyazov, Ra, Nozar, M, O'Rielly, Gv, Osipenko, Mikhail, Ostrovidov, Ai, Park, K, Pasyuk, E, Paterson, C, Philips, Sa, Pierce, J, Pivnyuk, N, Pocanic, D, Pogorelko, O, Polli, Ermanno, Pozdniakov, S, Preedom, Bm, Price, Jw, Prok, Y, Protopopescu, D, Qin, Lm, Raue, Ba, Riccardi, G, Ricco, Giovanni, Ripani, Marco, Rosner, G, Rossi, Patrizia, Rowntree, D, Rubin, Pd, Sabatie, F, Salgado, C, Santoro, Jp, Sapunenko, Vladimir, Schumacher, Ra, Serov, Vs, Sharabian, Yg, Shaw, J, Shvedunov, Nv, Skabelin, Av, Smith, Es, Smith, Lc, Sober, Di, Stavinsky, A, Stepanyan, Ss, Stepanyan, S, Stokes, Be, Stoler, P, Strauch, S, Suleiman, R, Taiuti, MAURO GINO, Taylor, S, Tedeschi, Dj, Thoma, U, Tkabladze, A, Tkachenko, S, Todor, L, Ungaro, M, Vineyard, Mf, Vlassov, Av, Weinstein, Lb, Weygand, Dp, Williams, M, Wolin, E, Wood, Mh, Yegneswaran, A, Yun, J, Zana, L, Zhang, J, Zhao, B, Zhao, Z., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Thomas Jefferson National Accelerator Facility (Jefferson Lab), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, CLAS, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
ELECTRON-SCATTERING, DEPENDENCE, CLAS, 25.30.Fj,13.60.Hb,27.20.+n, QUARK-HADRON DUALITY, FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], QUARK-HADRON DUALITY, ELECTRON-SCATTERING, DEPENDENCE, CLAS, Nuclear Experiment
Abstract

The (W,Q2)-dependence of the ratio of inclusive electron scattering cross sections for 15N/12C was determined in the kinematic range 0.8, Comment: 13 pages, 2 figures. Significantly shortened version. Results unchanged. Small additions for Phys. Rev. C

Published
2008

11. Separated Structure Functions for the Exclusive Electroproduction of $K^+\Lambda$ and $K^+\Sigma^0$ Final States

Author

Ambrozewicz, P, Carman, Ds, Feuerbach, Rj, Mestayer, Md, Raue, Ba, Schumacher, Ra, Tkabladze, A, Amarian, Mj, Anghinolfi, Marco, Asavapibhop, B, Asryan, G, Avakian, H, Bagdasaryan, H, Baillie, N, Ball, Jp, Baltzell, Na, Barrow, S, Batourine, V, Battaglieri, Marco, Beard, K, Bedlinskiy, I, Bektasoglu, M, Bellis, M, Benmouna, N, Berman, Bl, Bianchi, Nicola, Biselli, As, Bonner, Be, Bouchigny, S, Boiarinov, S, Bradford, R, Branford, D, Briscoe, Wj, Brooks, Wk, Bultmann, S, Burkert, Vd, Butuceanu, C, Calarco, Jr, Careccia, Sl, Cetina, C, Chen, S, Cole, Pl, Collins, P, Coltharp, P, Cords, D, Corvisiero, Pietro, Crabb, D, Crede, V, Cummings, Jp, Dashyan, N, De Masi, R, De Vita Raffaella, De Sanctis Enzo, Degtyarenko, Pv, Dennis, L, Deur, A, Dhuga, Ks, Dickson, R, Djalali, C, Dodge, Ge, Donnelly, J, Doughty, D, Dragovitsch, P, Dugger, M, Dytman, S, Dzyubak, Op, Egiyan, H, Egiyan, Ks, El Fassi, L, Elouadrhiri, L, Empl, A, Eugenio, P, Farhi, L, Fatemi, R, Fedotov, G, Feldman, Gerald, Forest, Ta, Frolov, V, Funsten, H, Garcon, M, Gavalian, G, Gilfoyle, Gp, Giovanetti, Kl, Girard, P, Girod, Fx, Goetz, Jt, Gonenc, A, Gothe, Rw, Griffioen, Ka, Guidal, M, Guillo, M, Guler, N, Guo, L, Gyurjyan, V, Hafidi, K, Hakobyan, H, Hardie, J, Heddle, D, Hersman, Fw, Hicks, K, Hleiqawi, I, Holtrop, M, Hu, J, Hyde Wright CE, Ilieva, Y, Ireland, Dg, Ishkhanov, Bs, Isupov, El, Ito, Mm, Jenkins, D, Jo, Hs, Joo, K, Juengst, Hg, Kalantarians, N, Kellie, Jd, Khandaker, M, Kim, Ky, Kim, K, Kim, W, Klein, A, Klein, Fj, Klusman, M, Kossov, M, Kramer, Lh, Kubarovsky, V, Kuhn, J, Kuhn, Se, Kuleshov, Sv, Lachniet, J, Laget, Jm, Langheinrich, J, Lawrence, D, Livingston, K, Lu, Hy, Lukashin, K, Maccormick, M, Manak, Jj, Markov, N, Mcaleer, S, Mckinnon, B, Mcnabb, Jwc, Mecking, Ba, Meyer, Ca, Mibe, T, Mikhailov, K, Minehart, R, Mirazita, Marco, Miskimen, R, Mokeev, V, Moriya, K, Morrow, Sa, Moteabbed, M, Muccifora, Valeria, Mueller, J, Mutchler, Gs, Nadel Turonski, P, Napolitano, J, Nasseripour, R, Niccolai, S, Niculescu, G, Niculescu, I, Niczyporuk, Bb, Niroula, Mr, Niyazov, Ra, Nozar, M, O'Rielly, Gv, Osipenko, Mikhail, Ostrovidov, Ai, Park, K, Pasyuk, E, Paterson, C, Philips, Sa, Pierce, J, Pivnyuk, N, Pocanic, D, Pogorelko, O, Polli, Ermanno, Pozdniakov, S, Preedom, Bm, Price, Jw, Prok, Y, Protopopescu, D, Qin, Lm, Riccardi, G, Ricco, Giovanni, Ripani, Marco, Ritchie, Bg, Ronchetti, Federico, Rosner, G, Rossi, Patrizia, Rowntree, D, Rubin, Pd, Sabatie, F, Salamanca, J, Salgado Lopez Carlos Alberto, Santoro, Joseph, Sapunenko, Vladimir, Sayre, D, Serov, Vs, Shafi, A, Sharabian, Yg, Shvedunov, Nv, Simionatto, S, Skabelin, Av, Smith, Es, Smith, Lc, Sober, Di, Sokhan, D, Stavinsky, A, Stepanyan, Ss, Stepanyan, S, Stokes, Be, Stoler, P, Strakovsky, Ii, Strauch, S, Taiuti, MAURO GINO, Taylor, S, Tedeschi, Dj, Thompson, R, Tkachenko, S, Tur, C, Ungaro, M, Vineyard, Mf, Vlassov, Av, Wang, K, Watts, Dp, Weinstein, Lb, Weygand, Dp, Williams Meurig Crispin Stowe, Wolin, E, Wood, Mh, Yegneswaran, A, Yun, J, Zana, L, Zhang, J, Zhao, B, Zhao, Zw, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Thomas Jefferson National Accelerator Laboraory (TJNAL), Thomas Jefferson National Accelerator Laboratory, Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), CLAS, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
KAON PHOTOPRODUCTION, PHOTON ENERGIES, CLAS, RESONANCES, MESONS, SCATTERING, DIRECTION, K&LAMBDA, P(GAMMA, LAMBDA, P(GAMMA, MESONS, LAMBDA, High Energy Physics - Experiment, CLAS, K&LAMBDA, PHOTON ENERGIES, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], SCATTERING, KAON PHOTOPRODUCTION, High Energy Physics::Experiment, Nuclear Experiment, RESONANCES, DIRECTION
Abstract

We report measurements of the exclusive electroproduction of $K^+\Lambda$ and $K^+\Sigma^0$ final states from a proton target using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The separated structure functions $\sigma_T$, $\sigma_L$, $\sigma_{TT}$, and $\sigma_{LT}$ were extracted from the $\Phi$- and $\epsilon$-dependent differential cross sections taken with electron beam energies of 2.567, 4.056, and 4.247 GeV. This analysis represents the first $\sigma_L/\sigma_T$ separation with the CLAS detector, and the first measurement of the kaon electroproduction structure functions away from parallel kinematics. The data span a broad range of momentum transfers from $0.5\leq Q^2\leq 2.8$ GeV$^2$ and invariant energy from $1.6\leq W\leq 2.4$ GeV, while spanning nearly the full center-of-mass angular range of the kaon. The separated structure functions reveal clear differences between the production dynamics for the $\Lambda$ and $\Sigma^0$ hyperons. These results provide an unprecedented data sample with which to constrain current and future models for the associated production of strangeness, which will allow for a better understanding of the underlying resonant and non-resonant contributions to hyperon production., Comment: 61 pages, 26 figures, 5 tables

Published
2006

12. Quark-Hadron Duality in Spin Structure Functions g1p and g1d

Author

Bosted, Pe, Dharmawardane, Kv, Dodge, Ge, Forest, Ta, Kuhn, Se, Prok, Y, Adams, G, Amarian, M, Ambrozewicz, P, Anghinolfi, Marco, Asryan, G, Avakian, H, Bagdasaryan, H, Baillie, N, Ball, Jp, Baltzell, Na, Barrow, S, Batourine, V, Battaglieri, Marco, Beard, K, Bedlinskiy, I, Bektasoglu, M, Bellis, M, Benmouna, N, Biselli, As, Bonner, Be, Bouchigny, S, Boiarinov, S, Bradford, R, Branford, D, Brooks, Wk, Bultmann, S, Burkert, Vd, Butuceanu, C, Calarco, Jr, Careccia, Sl, Carman, Ds, Carnahan, B, Cazes Antoine Jacques, Chen, S, Cole, Pl, Collins, P, Coltharp, P, Cords, D, Corvisiero, Pietro, Crabb, D, Crannell, H, Crede, V, Cummings, Jp, De Masi, R, Devita, R, De Sanctis Enzo, Degtyarenko, Pv, Denizli, H, Dennis, L, Deur, A, Djalali, C, Donnelly, J, Doughty, D, Dragovitsch, P, Dugger, M, Dytman, S, Dzyubak, Op, Egiyan, H, Egiyan, Ks, Elouadrhiri, L, Eugenio, P, Fatemi, R, Fedotov, G, Feuerbach, Rj, Funsten, H, Garcon, M, Gavalian, G, Gilfoyle, Gp, Giovanetti, Kl, Girod, Fx, Goetz, Jt, Golovatch, Evgueni, Gonenc, A, Gothe, Rw, Griffioen, Ka, Guidal, M, Guillo, M, Guler, N, Guo, L, Gyurjyan, V, Hadjidakis, Cynthia, Hafidi, K, Hakobyan, Rs, Hardie, J, Heddle, D, Hersman, Fw, Hicks, K, Hleiqawi, I, Holtrop, M, Huertas, M, Hyde Wright CE, Ilieva, Y, Ireland, Dg, Ishkhanov, Bs, Isupov, El, Ito, Mm, Jenkins, D, Jo, Hs, Joo, K, Juengst, Hg, Keith, C, Kellie, Jd, Khandaker, M, Kim, Ky, Kim, K, Kim, W, Klein, A, Klein, Fj, Klusman, M, Kossov, M, Kramer, Lh, Kubarovsky, V, Kuhn, J, Kuleshov, Sv, Lachniet, J, Laget, Jm, Langheinrich, J, Lawrence, D, Jun, Li, Lima, Acs, Livingston, K, Lu, H, Lukashin, K, Maccormick, M, Manak, Jj, Markov, N, Mcaleer, S, Mckinnon, B, Mcnabb, Jwc, Mecking, Ba, Mestayer, Md, Meyer, Ca, Mibe, T, Mikhailov, K, Minehart, R, Mirazita, Marco, Miskimen, R, Mokeev, V, Morand, L, Morrow, Sa, Moteabbed, M, Mueller, J, Mutchler, Gs, Nadel Turonski, P, Napolitano, J, Nasseripour, R, Niccolai, S, Niculescu, G, Niculescu, I, Niczyporuk, Bb, Niroula, Mr, Niyazov, Ra, Nozar, M, O'Rielly, Gv, Osipenko, Mikhail, Ostrovidov, Ai, Park, K, Pasyuk, E, Paterson, C, Philips, Sa, Pierce, J, Pivnyuk, N, Pocanic, D, Pogorelko, O, Polli, Ermanno, Pozdniakov, S, Preedom, Bm, Price, Jw, Protopopescu, D, Qin, Lm, Raue, Ba, Riccardi, G, Ricco, Giovanni, Ripani, Marco, Ronchetti, Federico, Rosner, G, Rossi, Patrizia, Rowntree, D, Rubin, Pd, Sabatie, F, Salgado Lopez Carlos Alberto, Santoro, Joseph, Sapunenko, Vladimir, Schumacher, Ra, Serov, Vs, Sharabian, Yg, Shaw, J, Shvedunov, Nv, Skabelin, Av, Smith, Es, Smith, Lc, Sober, Di, Stavinsky, A, Stepanyan, Ss, Stepanyan, S, Stokes, Be, Stoler, P, Strauch, S, Suleiman, R, Taiuti, MAURO GINO, Taylor, S, Tedeschi, Dj, Thoma, U, Thompson, R, Tkabladze, A, Tkachenko, S, Todor, L, Tur, C, Ungaro, M, Vineyard, Mf, Vlassov, Av, Weinstein, Lb, Weygand, Dp, Williams Meurig Crispin Stowe, Wolin, E, Wood, Mh, Yegneswaran, A, Yun, J, Zana, L, Zhang, J, Zhao, B, Zhao, Z., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), CLAS, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
RESONANCE-REGION, LOCAL DUALITY, FORM-FACTORS, SCATTERING, NUCLEON, TARGET, ELECTROPRODUCTION, ASYMMETRY, BEHAVIOR, PROTON, FORM-FACTORS, 13.60.Hb, 25.30.Fj, 24.30.Gd, ELECTROPRODUCTION, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], LOCAL DUALITY, PROTON, High Energy Physics - Phenomenology, TARGET, High Energy Physics - Phenomenology (hep-ph), [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], RESONANCE-REGION, ASYMMETRY, SCATTERING, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), NUCLEON, Nuclear Experiment, BEHAVIOR
Abstract

New measurements of the spin structure functions of the proton and deuteron g1p(x,Q2) and g1d(x,Q2) in the nucleon resonance region are compared with extrapolations of target-mass-corrected next-to-leading-order (NLO) QCD fits to higher energy data. Averaged over the entire resonance region (W1.7 GeV2. This global duality appears to result from cancellations among the prominent local resonance regions: in particular strong sigma{3/2} contributions in the Delta(1232) region appear to be compensated by strong sigma{1/2} contributions in the resonance region centered on 1.5 GeV. These results are encouraging for the extension of NLO QCD fits to lower W and Q2 than have been used previously., 15 pages, 3 figures

Published
2006
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13. Deeply virtual and exclusive electroproduction of $\omega$-mesons

Author

Morand, L, Dore, D, Garcon, M, Guidal, M, Laget, Jm, Morrow, S, Sabatie, F, Smith, E, Adams, G, Arnbrozewicz, P, Anghinolfi, Marco, Asryan, G, Audit, G, Avakian, H, Bagdasaryan, H, Ball, J, Ball, Jp, Baltzell, Na, Barrow, S, Batourine, V, Battaglieri, Marco, Bektasoglu, M, Bellis, M, Benmouna, N, Berman, Bl, Biselli, As, Boiarinov, S, Bonner, Be, Bouchigny, S, Bradford, R, Branford, D, Briscoe, Wj, Brooks, Wk, Bultmann, S, Burkert, Vd, Butuceanu, C, Calarco, Jr, Careccia, Sl, Carman, Ds, Cazes Antoine Jacques, Chen, S, Cole, Pl, Cords, D, Corvisiero, Pietro, Crabb, D, Cummings, Jp, De Sanctis Enzo, Devita, R, Degtyarenko, Pv, Denizli, H, Dennis, L, Deur, A, Dharmawardane, Kv, Dhuga, Ks, Djalali, C, Dodge, Ge, Donnelly, J, Doughty, D, Dugger, M, Dytman, S, Dzyubak, Op, Egiyan, H, Egiyan, Ks, Elouadrhiri, L, Eugenio, P, Fatemi, R, Feldman, Gerald, Fersch, Rg, Feuerbach, Rj, Funsten, H, Gavalian, G, Gilfoyle, Gp, Giovanetti, Kl, Girod, Fx, Goetz, Jt, Gordon, Cio, Gothe, Rw, Griffioen, Ka, Guillo, M, Guler, N, Guo, L, Gyurjyan, V, Hadjidakis, Cynthia, Hakobyan, Rs, Hardie, J, Heddle, D, Hersman, Fw, Hicks, K, Hleiqawi, I, Holtrop, M, Hyde Wright CE, Ilieva, Y, Ireland, Dg, Ito, Mm, Jenkins, D, Jo, Hs, Joo, K, Juengst, Hg, Kellie, Jd, Khandaker, M, Kim, W, Klein, A, Klein, Fj, Klimenko, Av, Kossov, M, Kubarovski, V, Kramer, Lh, Kuhn, Se, Kuhn, J, Lachniet, J, Langhenirich, J, Lawrence, D, Lee, T, Jun, Li, Livingston, K, Marchand, C, Maximon, Lc, Mcaleer, S, Mckinnon, B, Mcnabb, Jwc, Mecking, Ba, Mehrabyan, S, Melone, Jj, Mestayer, Md, Meyer, Ca, Mikhailov, K, Minehart, R, Mirazita, Marco, Miskimen, R, Mokeev, V, Mueller, J, Mutchler, Gs, Napolitano, J, Nasseripour, R, Niccolai, S, Niculescu, G, Niculescu, I, Niczyporuk, Bb, Niyazov, Ra, Nozar, M, O'Rielly, Gv, Osipenko, Mikhail, Ostrovidov, Ai, Park, K, Pasyuk, E, Philips, Sa, Pivnyuk, N, Pocanic, D, Pogorelko, O, Polli, Ermanno, Popa, I, Pozdniakov, S, Preedom, Bm, Price, Jw, Prok, Y, Protopopescu, D, Raue, Ba, Riccardi, G, Ricco, Giovanni, Ripani, Marco, Ritchie, Bg, Ronchetti, Federico, Rosner, G, Rossi, Patrizia, Rubin, Pd, Salgado Lopez Carlos Alberto, Santoro, Joseph, Sapunenko, Vladimir, Schumacher, Ra, Serov, Vs, Sharabian, Yg, Shaw, J, Skabelin, Av, Smith, Lc, Sober, Di, Stavinsky, A, Stepanyan, S, Stepanyan, Ss, Stokes, Be, Stoler, P, Strakovsky, Ii, Strauch, S, Taiuti, MAURO GINO, Tedeschi, Dj, Thoma, U, Tkabladze, A, Todor, L, Tur, C, Ungaro, M, Vineyard, Mf, Vlassov, Av, Weinstein, Lb, Weygand, Dp, Williams Meurig Crispin Stowe, Wolin, E, Wood, Mh, Yegneswaran, A, Zana, L., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and CLAS

Subjects
Nuclear and High Energy Physics, Particle physics, Photon, Meson, Proton, Nuclear Theory, FOS: Physical sciences, Parton, 13.60.Le - 12.40.Nn -12.38.Bx, 01 natural sciences, Omega, Resonance (particle physics), High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), GENERALIZED PARTON DISTRIBUTIONS, CLAS, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], SCATTERING, 010306 general physics, Nuclear Experiment, Coupling, Physics, 010308 nuclear & particles physics, HYDROGEN, PHOTON, SPIN, GENERALIZED PARTON DISTRIBUTIONS, VECTOR-MESONS, SCATTERING, PHOTON, HYDROGEN, SPIN, CLAS, High Energy Physics::Experiment, Nucleon, VECTOR-MESONS
Abstract

The exclusive omega electroproduction off the proton was studied in a large kinematical domain above the nucleon resonance region and for the highest possible photon virtuality (Q2) with the 5.75 GeV beam at CEBAF and the CLAS spectrometer. Cross sections were measured up to large values of the four-momentum transfer (-t < 2.7 GeV2) to the proton. The contributions of the interference terms sigma_TT and sigma_TL to the cross sections, as well as an analysis of the omega spin density matrix, indicate that helicity is not conserved in this process. The t-channel pi0 exchange, or more generally the exchange of the associated Regge trajectory, seems to dominate the reaction gamma* p -> omega p, even for Q2 as large as 5 GeV2. Contributions of handbag diagrams, related to Generalized Parton Distributions in the nucleon, are therefore difficult to extract for this process. Remarkably, the high-t behaviour of the cross sections is nearly Q2-independent, which may be interpreted as a coupling of the photon to a point-like object in this kinematical limit., 15 pages,19 figures

Published
2005

14. Measurement of the Polarized Structure Function $\sigma_{LT^\prime}$ for Pion Electroproduction in the Roper Resonance Region

Author

Joo, K, Smith, Lc, Aznauryan, Ig, Burkert, Vd, Egiyan, H, Minehart, R, Adams, G, Ambrozewicz, P, Anciant, E, Anghinolfi, Marco, Asavapibhop, B, Asryan, G, Audit, G, Auger, T, Avakian, H, Bagdasaryan, H, Baillie, N, Ball, Jp, Baltzell, Na, Barrow, S, Batourine, V, Battaglieri, Marco, Beard, K, Bedlinskiy, I, Bektasoglu, M, Bellis, M, Benmouna, N, Berman, Bl, Bianchi, Nicola, Biselli, As, Bonner, Be, Bouchigny, S, Boiarinov, S, Bradford, R, Branford, D, Briscoe, Wj, Brooks, Wk, Bueltmann, S, Butuceanu, C, Calarco, Jr, Careccia, Sl, Carman, Ds, Carnahan, B, Cetina, C, Chen, S, Cole, Pl, Coleman, A, Coltharp, P, Cords, D, Corvisiero, Pietro, Crabb, D, Cummings, Jp, De Sanctis Enzo, Devita, R, Degtyarenko, Pv, Dennis, L, Deur, A, Dharmawardane, Kv, Dhuga, Ks, Djalali, C, Dodge, Ge, Donnelly, J, Doughty, D, Dragovitsch, P, Dugger, M, Dytman, S, Dzyubak, Op, Egiyan, Ks, Elouadrhiri, L, Empl, A, Eugenio, P, Farhi, L, Fatemi, R, Fedotov, G, Feldman, Gerald, Feuerbach, Rj, Forest, Ta, Frolov, V, Funsten, H, Gaff, Sj, Garcon, M, Gavalian, G, Gilfoyle, Gp, Giovanetti, Kl, Girard, P, Girod, Fx, Goetz, Jt, Gothe, Rw, Griffioen, Ka, Guidal, M, Guillo, M, Guler, N, Guo, L, Gyurjyan, V, Hakobyan, Rs, Hardie, J, Heddle, D, Hersman, Fw, Hicks, K, Hleiqawi, I, Holtrop, M, Hu, J, Hyde Wright CE, Ilieva, Y, Ireland, Dg, Ishkhanov, Bs, Ito, Mm, Jenkins, D, Jo, Hs, Juengst, Hg, Kelley, Jh, Kellie, Jd, Khandaker, M, Kim, Ky, Kim, K, Kim, W, Klein, A, Klein, Fj, Klimenko, Av, Klusman, M, Kossov, M, Kramer, Lh, Kubarovsky, V, Kuhn, J, Kuhn, Se, Lachniet, J, Laget, Jm, Langheinrich, J, Lawrence, D, Lee, T, Livingston, K, Lukashin, K, Manak, Jj, Marchand, C, Maximon, Lc, Mcaleer, S, Mckinnon, B, Mcnabb, Jwc, Mecking, Ba, Mestayer, Md, Meyer, Ca, Mikhailov, K, Mirazita, Marco, Miskimen, R, Mokeev, V, Morrow, Sa, Muccifora, Valeria, Mueller, J, Mutchler, Gs, Nadel Turonski, P, Napolitano, J, Nasseripour, R, Nelson, So, Niccolai, S, Niculescu, G, Niculescu, I, Niczyporuk, Bb, Niyazov, Ra, Nozar, M, O'Rielly, Gv, Osipenko, Mikhail, Ostrovidov, Ai, Park, K, Pasyuk, E, Peterson, G, Philips, Sa, Pierce, J, Pivnyuk, N, Pocanic, D, Pogorelko, O, Polli, Ermanno, Pozdniakov, S, Preedom, Bm, Price, Jw, Prok, Y, Protopopescu, D, Qin, Lm, Raue, Ba, Riccardi, G, Ricco, Giovanni, Ripani, Marco, Ritchie, Bg, Ronchetti, Federico, Rosner, G, Rossi, Patrizia, Rowntree, D, Rubin, Pd, Sabatie, F, Sabourov, K, Salgado Lopez Carlos Alberto, Santoro, Joseph, Sapunenko, Vladimir, Schumacher, Ra, Serov, Vs, Shafi, A, Sharabian, Yg, Shaw, J, Simionatto, S, Skabelin, Av, Smith, Es, Sober, Di, Spraker, M, Stavinsky, A, Stepanyan, Ss, Stepanyan, S, Stokes, Be, Stoler, P, Strakovsky, Ii, Strauch, S, Taiuti, MAURO GINO, Taylor, S, Tedeschi, Dj, Thoma, U, Thompson, R, Tkabladze, A, Tur, C, Ungaro, M, Vineyard, Mf, Vlassov, Av, Wang, K, Weinstein, Lb, Weller, H, Weygand, Dp, Williams Meurig Crispin Stowe, Wolin, E, Wood, Mh, Yegneswaran, A, Yun, J, Zana, L, Zhang, J., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and CLAS

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

The polarized longitudinal-transverse structure function $\sigma_{LT^\prime}$ measures the interference between real and imaginary amplitudes in pion electroproduction and can be used to probe the coupling between resonant and non-resonant processes. We report new measurements of $\sigma_{LT^\prime}$ in the $N(1440){1/2}^+$ (Roper) resonance region at $Q^2=0.40$ and 0.65 GeV$^2$ for both the $\pi^0 p$ and $\pi^+ n$ channels. The experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at a beam energy of 1.515 GeV. Complete angular distributions were obtained and are compared to recent phenomenological models. The $\sigma_{LT^\prime}(\pi^+ n)$ channel shows a large sensitivity to the Roper resonance multipoles $M_{1-}$ and $S_{1-}$ and provides new constraints on models of resonance formation., Comment: 5 pages, 3 figures. Revised manuscript accepted by Physical Review C (Brief Report)

Published
2005

15. Tensor polarization of the $\phi$ meson photoproduced at high $t$

Author

McCormick, K., Audit, G., Laget, J.M., Guo, L., Weygand, D.P., Niyazov, R.A., Weinstein, L.B., Carman, D.S., Joo, K., Mestayer, M.D., Raue, B.A., De Vita, R., Anghinolfi, M., Burkert, V.D., Dodge, G.E., Minehart, R., Taiuti, M., Weller, H., Adams, G., Amaryan, M.J., Anciant, E., Armstrong, D.S., Asavapibhop, B., Asryan, G., Auger, T., Avakian, H., Bagdasaryan, H., Ball, J.P., Barrow, S., Battaglieri, M., Beard, K., Bektasoglu, M., Bianchi, N., Biselli, A.S., Boiarinov, S., Bonner, B.E., Bosted, P., Bouchigny, S., Branford, D., Brooks, W.K., Bueltmann, S., Calarco, J.R., Capitani, G.P., Carnahan, B., Cazes, A., Ciciani, L., Cole, P.L., Coleman, A., Connelly, J., Cords, D., Corvisiero, P., Crabb, D., Crannell, H., Cummings, J.P., De-Sanctis, E., Degtyarenko, P.V., Demirchyan, R., Denizli, H., Dennis, L., Dharmawardane, K.V., Dhuga, K.S., Djalali, C., Doughty, D., Dragovitsch, P., Dugger, M., Dytman, S., Eckhause, M., Egiyan, H., Egiyan, K.S., Elouadrhiri, L., Empl, A., Farhi, L., Fatemi, R., Feuerbach, R.J., Ficenec, J., Forest, T.A., Frolov, V., Funsten, H., Gaff, S.J., Gai, M., Garcon, M., Gavalian, G., Gilad, S., Gilfoyle, G.P., Giovanetti, K.L., Girard, Pascal, Golovatch, E., Griffioen, K., Guidal, M., Guillo, M., Gyurjyan, V., Hadjidakis, C., Hancock, D., Hardie, J., Heddle, D., Heimberg, P., Hersman, F.W., Hicks, K., Hicks, R.S., Holtrop, M., Hu, J., Hyde-Wright, C.E., Ishkanov, B.S., Ito, M.M., Jenkins, D., Kelley, J.H., Kellie, J.D., Khandaker, M., Kim, K.Y., Kim, K., Kim, W., Klein, A., Klein, F.J., Klusman, M., Kossov, M., Kramer, L.H., Kuang, Y., Kuhn, S.E., Lachniet, J., Lawrence, D., Li, J., Livingston, K., Longhi, A., Loukachine, K., Lucas, M., Major, W., Manak, J.J., Marchand, C., McAleer, S., McCarthy, J., McNabb, J.W.C., Mecking, B.A., Meyer, C.A., Mikhailov, K.., Mirazita, M., Miskimen, R., Mokeev, V., Muccifora, V., Mueller, J., Mutchler, G.S., Napolitano, J., Nelson, S.O., Niculescu, G., Niculescu, I., Niczyporuk, B.B., Opper, A.K., O'Rielly, G.V., Osipenko, M., Park, K., Pasyuk, E., Peterson, G., Philips, S.A., Pivnyuk, N., Pocanic, D., Pogorelko, O., Polli, E., Pozdniakov, S., Preedom, B.M., Price, J.W., Prok, Y., Protopopescu, D., Qin, L.M., Reolon, A.R., Riccardi, G., Ricco, G., Ripani, M., Ritchie, B.G., Rock, S., Ronchetti, F., Rossi, P., Rowntree, D., Rubin, P.D., Sabatie, F., Sabourov, K., Salgado, C., Sapunenko, V., Sargsyan, M., Schumacher, R.A., Serov, V.S., Shafi, A., Sharabian, Y.G., Shaw, J., Skabelin, A.V., Smith, E.S., Smith, T., Smith, L.C., Sober, D.I., Sorrell, L., Spraker, M., Stavinsky, A., Stepanyan, S., Stoler, P., Strakovsky, I.I., Taylor, S., Tedeschi, D.J., Thompson, R., Todor, L., Ungaro, M., Vineyard, M.F., Vlassov, A.V., Wang, K., Weisberg, A., Whisnant, C.S., Wolin, E., Yegneswaran, A., Yun, J., Zhang, B., Zhao, J., Zhou, Z., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and CLAS

Subjects
EXCHANGE-POTENTIAL APPROACH, FOS: Physical sciences, High Energy Physics - Experiment, NUCLEON-SCATTERING, High Energy Physics - Experiment (hep-ex), EXCHANGE-POTENTIAL APPROACH, BARYON-BARYON SCATTERING, LARGE MOMENTUM-TRANSFER, VECTOR-MESONS, NUCLEON-SCATTERING, CLAS, SYSTEM, LARGE MOMENTUM-TRANSFER, CLAS, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Experiment, Nuclear Experiment, BARYON-BARYON SCATTERING, VECTOR-MESONS, SYSTEM
Abstract

As part of a measurement of the cross section of $\phi$ meson photoproduction to high momentum transfer, we measured the polar angular decay distribution of the outgoing $K^+$ in the channel $\phi \to K^+K^-$ in the $\phi$ center-of-mass frame (the helicity frame). We find that s-channel helicity conservation (SCHC) holds in the kinematical range where $t$-channel exchange dominates (up to $-t \sim 2.5$ GeV$^2$ for $E_{\gamma}$=3.6 GeV). Above this momentum, $u$-channel production of a $\phi$ meson dominates and induces a violation of SCHC. The deduced value of the $\phi NN$ coupling constant lies in the upper range of previously reported values., Comment: 6 pages; 5 figures

Published
2004

16. Measurement of the x- and Q2-dependence of the asymmetry A1 on the nucleon

Author

Dharmawardane, Kv, Kuhn, Se, Bosted, P, Prok, Y, Adams, G, Ambrozewicz, P, Anghinolfi, Marco, Asryan, G, Avakian, H, Bagdasaryan, H, Baillie, N, Ball, Jp, Baltzell, Na, Barrow, S, Batourine, V, Battaglieri, Marco, Beard, K, Bedlinskiy, I, Bektasoglu, M, Bellis, M, Benmouna, N, Biselli, As, Bonner, Be, Bouchigny, S, Boiarinov, S, Bradford, R, Branford, D, Brooks, Wk, Bultmann, S, Burkert, Vd, Butuceanu, C, Calarco, Jr, Careccia, Sl, Carman, Ds, Carnahan, B, Cazes Antoine Jacques, Chen, S, Cole, Pl, Collins, P, Coltharp, P, Cords, D, Corvisiero, Pietro, Crabb, D, Crannell, H, Crede, V, Cummings, Jp, De Masi, R, Devita, R, De Sanctis Enzo, Degtyarenko, Pv, Denizli, H, Dennis, L, Deur, A, Djalali, C, Dodge, Ge, Donnelly, J, Doughty, D, Draigovitsch, P, Dugger, M, Dytman, S, Dzyubak, Op, Egiyan, H, Egiyan, Ks, Elouadrhiri, L, Eugenio, P, Fatemi, R, Fedotov, G, Feuerbach, Rj, Forest, Ta, Funsten, H, Garcon, M, Gavalian, G, Gilfoyle, Gp, Giovanetti, Kl, Girod, Fx, Goetz, Jt, Golovatch, Evgueni, Gonenc, A, Gothe, Rw, Griffioen, Ka, Guidal, M, Guillo, M, Guler, N, Guo, L, Gyurjyan, V, Hadjidakis, Cynthia, Hafidi, K, Hakobyan, Rs, Hardie, J, Heddle, D, Hersman, Fw, Hicks, K, Hleiqawi, I, Holtrop, M, Huertas, M, Hyde Wriyht CE, Ilieva, Y, Ireland, Dg, Ishkhanov, Bs, Isupov, El, Ito, Mm, Jenkins, D, Jo, Hs, Joo, K, Juengst, Hg, Keith, C, Kellie, Jd, Khandaker, M, Kim, Ky, Kim, K, Kim, W, Klein, A, Klein, Fj, Klusman, M, Kossov, M, Kramer, Lh, Kubarovsky, V, Kuhn, J, Kuleshov, Sv, Lachniet, J, Laget, Jm, Langheinrich, J, Lawrence, D, Jun, Li, Lima, Acs, Livingston, K, Lu, H, Lukashin, K, Maccormick, M, Manak, Jj, Markov, N, Mcaleer, S, Mckinnon, B, Mcnabb, Jwc, Mecking, Ba, Mestayer, Md, Meyer, Ca, Mibe, T, Mikhailov, K, Minehart, R, Mirazita, Marco, Miskimen, R, Mokeev, V, Morand, L, Morrow, Sa, Moteabbed, M, Mueller, J, Mutchler, Gs, Nadel Turonski, P, Napolitano, J, Nasseripour, R, Niccolai, S, Niculescu, G, Niculescu, I, Niczyporuk, Bb, Niroula, Mr, Nyazov, Ra, Nozar, M, O'Rielly, Gv, Osipenko, Mikhail, Ostrovidov, Ai, Park, K, Pasyuk, E, Paterson, C, Philips, Sa, Pierce, J, Pivnyuk, N, Pocanic, D, Pogorelko, O, Polli, Ermanno, Pozdniakov, S, Preedom, Bm, Price, Jw, Protopopescu, D, Qin, Lm, Raue, Ba, Riccardi, G, Ricco, Giovanni, Ripani, Marco, Ritchie, Bg, Ronchetti, Federico, Rosner, G, Rossi, Patrizia, Rowntree, D, Rubin, Pd, Sabatie, E, Salgado Lopez Carlos Alberto, Santoro, Joseph, Sapunenko, Vladimir, Schumacher, Ra, Serov, Vs, Sharabian, Yg, Shaw, J, Shvedunov, Nv, Skabelin, Av, Smith, Es, Smith, Lc, Sober, Di, Stavinsky, A, Stepanyan, Ss, Stepanyan, S, Stokes, Be, Stoler, P, Strakovsky, Ii, Strauch, S, Suleiman, R, Taiuti, MAURO GINO, Taylor, S, Tedeschi, Dj, Thoma, U, Thompson, R, Tkabladze, A, Tkachenko, S, Todor, L, Tur, C, Ungaro, M, Vineyard, Mf, Vlassov, Av, Weinstein, Lb, Weygand, Dp, Williams Meurig Crispin Stowe, Wolin, E, Wood, Mh, Yegneswaran, A, Yun, J, Zana, L, Zhang, J, Zhao, B, Zhao, Z., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), CLAS, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
DEEP-INELASTIC-SCATTERING, Spin structure functions, QUARK, FOS: Physical sciences, 13.60.Hb, 13.88.+e, 14.20.Dh, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], PROTON, SUM-RULE, NEUTRON SPIN STRUCTURE, Nucleon structure, G(1)(N), CLAS, PION, DISTRIBUTIONS, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), NEUTRON SPIN STRUCTURE, DEEP-INELASTIC-SCATTERING, SUM-RULE, PROTON, DISTRIBUTIONS, G(1)(N), QUARK, CLAS, PION, Nuclear Experiment
Abstract

We report results for the virtual photon asymmetry $A_1$ on the nucleon from new Jefferson Lab measurements. The experiment, which used the CEBAF Large Acceptance Spectrometer and longitudinally polarized proton ($^{15}$NH$_3$) and deuteron ($^{15}$ND$_3$) targets, collected data with a longitudinally polarized electron beam at energies between 1.6 GeV and 5.7 GeV. In the present paper, we concentrate on our results for $A_1(x,Q^2)$ and the related ratio $g_1/F_1(x,Q^2)$ in the resonance and the deep inelastic regions for our lowest and highest beam energies, covering a range in momentum transfer $Q^2$ from 0.05 to 5.0 GeV$^2$ and in final-state invariant mass $W$ up to about 3 GeV. Our data show detailed structure in the resonance region, which leads to a strong $Q^2$--dependence of $A_1(x,Q^2)$ for $W$ below 2 GeV. At higher $W$, a smooth approach to the scaling limit, established by earlier experiments, can be seen, but $A_1(x,Q^2)$ is not strictly $Q^2$--independent. We add significantly to the world data set at high $x$, up to $x = 0.6$. Our data exceed the SU(6)-symmetric quark model expectation for both the proton and the deuteron while being consistent with a negative $d$-quark polarization up to our highest $x$. This data setshould improve next-to-leading order (NLO) pQCD fits of the parton polarization distributions., Comment: 7 pages LaTeX, 5 figures

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