Author: "J. M. Laget" - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"J. M. Laget"' showing total 169 results

Start Over Author "J. M. Laget"

169 results on '"J. M. Laget"'

1. A multidimensional study of the structure function ratio σLT′/σ0 from hard exclusive π+ electro-production off protons in the GPD regime

Author: S. Diehl, A. Kim, K. Joo, P. Achenbach, Z. Akbar, M.J. Amaryan, H. Atac, H. Avagyan, C. Ayerbe Gayoso, L. Baashen, L. Barion, M. Bashkanov, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, A.S. Biselli, M. Bondi, W.A. Booth, F. Bossù, S. Boiarinov, K.-Th. Brinkmann, W.J. Briscoe, S. Bueltmann, D. Bulumulla, V.D. Burkert, D.S. Carman, A. Celentano, P. Chatagnon, V. Chesnokov, T. Chetry, G. Ciullo, G. Clash, P.L. Cole, M. Contalbrigo, G. Costantini, A. D'Angelo, N. Dashyan, R. De Vita, M. Defurne, A. Deur, C. Djalali, R. Dupre, H. Egiyan, M. Ehrhart, A. El Alaoui, L. El Fassi, L. Elouadrhiri, S. Fegan, A. Filippi, G. Gavalian, Y. Ghandilyan, G.P. Gilfoyle, D.I. Glazier, A.A. Golubenko, G. Gosta, R.W. Gothe, Y. Gotra, K.A. Griffioen, M. Guidal, K. Hafidi, H. Hakobyan, M. Hattawy, T.B. Hayward, D. Heddle, A. Hobart, M. Holtrop, Y. Ilieva, D.G. Ireland, E.L. Isupov, H.S. Jo, M. Khachatryan, A. Khanal, W. Kim, A. Kripko, V. Kubarovsky, V. Lagerquist, J.-M. Laget, L. Lanza, M. Leali, S. Lee, P. Lenisa, X. Li, K. Livingston, I. .J .D. MacGregor, D. Marchand, V. Mascagna, B. McKinnon, Z.E. Meziani, S. Migliorati, T. Mineeva, M. Mirazita, V. Mokeev, E. Molina, R.A. Montgomery, C. Munoz Camacho, P. Nadel-Turonski, P. Naidoo, K. Neupane, S. Niccolai, M. Nicol, G. Niculescu, M. Osipenko, M. Ouillon, P. Pandey, M. Paolone, L.L. Pappalardo, R. Paremuzyan, E. Pasyuk, S.J. Paul, W. Phelps, N. Pilleux, M. Pokhrel, J. Poudel, J.W. Price, Y. Prok, T. Reed, J. Richards, M. Ripani, J. Ritman, P. Rossi, F. Sabatié, C. Salgado, S. Schadmand, A. Schmidt, Y. Sharabian, E.V. Shirokov, U. Shrestha, P. Simmerling, D. Sokhan, N. Sparveris, M. Spreafico, S. Stepanyan, I.I. Strakovsky, S. Strauch, J.A. Tan, N. Trotta, M. Turisini, R. Tyson, M. Ungaro, S. Vallarino, L. Venturelli, H. Voskanyan, E. Voutier, D.P. Watts, X. Wei, R. Williams, R. Wishart, M.H. Wood, N. Zachariou, J. Zhang, Z.W. Zhao, and M. Zurek
Subjects: Exclusive single pion, Eletroproduction, GPD, CLAS12, Physics, QC1-999
Abstract: A multidimensional extraction of the structure function ratio σLT′/σ0 from the hard exclusive e→p→e′nπ+ reaction above the resonance region has been performed. The study was done based on beam-spin asymmetry measurements using a 10.6 GeV incident electron beam on a liquid-hydrogen target and the CLAS12 spectrometer at Jefferson Lab. The measurements focus on the very forward regime (t/Q2 ≪ 1) with a wide kinematic range of xB in the valence regime (0.17 < xB < 0.55), and virtualities Q2 ranging from 1.5 GeV2 up to 6 GeV2. The results and their comparison to theoretical models based on Generalized Parton Distributions demonstrate the sensitivity to chiral-odd GPDs and the directly related tensor charge of the nucleon. In addition, the data is compared to an extension of a Regge formalism at high photon virtualities. It was found that the Regge model provides a better description at low Q2, while the GPD model is more appropriate at high Q2.
Published: 2023
Full Text: View/download PDF

2. Hard exclusive pion electroproduction at backward angles with CLAS

Author: K. Park, M. Guidal, R.W. Gothe, B. Pire, K. Semenov-Tian-Shansky, J.-M. Laget, K.P. Adhikari, S. Adhikari, Z. Akbar, H. Avakian, J. Ball, I. Balossino, N.A. Baltzell, L. Barion, M. Battaglieri, I. Bedlinskiy, A.S. Biselli, W.J. Briscoe, W.K. Brooks, V.D. Burkert, F.T. Cao, D.S. Carman, A. Celentano, G. Charles, T. Chetry, G. Ciullo, L. Clark, P.L. Cole, M. Contalbrigo, V. Crede, A. D'Angelo, N. Dashyan, R. De Vita, E. De Sanctis, M. Defurne, A. Deur, C. Djalali, R. Dupre, H. Egiyan, A. El Alaoui, L. El Fassi, L. Elouadrhiri, P. Eugenio, G. Fedotov, R. Fersch, A. Filippi, M. Garçon, Y. Ghandilyan, G.P. Gilfoyle, F.X. Girod, E. Golovatch, K.A. Griffioen, L. Guo, K. Hafidi, H. Hakobyan, C. Hanretty, N. Harrison, M. Hattawy, D. Heddle, K. Hicks, M. Holtrop, C.E. Hyde, Y. Ilieva, D.G. Ireland, B.S. Ishkhanov, E.L. Isupov, D. Jenkins, S. Johnston, K. Joo, M.L. Kabir, D. Keller, G. Khachatryan, M. Khachatryan, M. Khandaker, W. Kim, F.J. Klein, V. Kubarovsky, S.E. Kuhn, L. Lanza, K. Livingston, I.J.D. MacGregor, N. Markov, B. McKinnon, M. Mirazita, V. Mokeev, R.A. Montgomery, C. Munoz Camacho, P. Nadel-Turonski, S. Niccolai, G. Niculescu, M. Osipenko, M. Paolone, R. Paremuzyan, E. Pasyuk, W. Phelps, O. Pogorelko, J. Poudel, J.W. Price, Y. Prok, D. Protopopescu, M. Ripani, A. Rizzo, P. Rossi, F. Sabatié, C. Salgado, R.A. Schumacher, Y. Sharabian, Iu. Skorodumina, G.D. Smith, D. Sokhan, N. Sparveris, S. Stepanyan, I.I. Strakovsky, S. Strauch, M. Taiuti, J.A. Tan, M. Ungaro, H. Voskanyan, E. Voutier, X. Wei, N. Zachariou, and J. Zhang
Subjects: Physics, QC1-999
Abstract: We report on the first measurement of cross sections for exclusive deeply virtual pion electroproduction off the proton, ep→e′nπ+, above the resonance region at backward pion center-of-mass angles. The φπ⁎-dependent cross sections were measured, from which we extracted three combinations of structure functions of the proton. Our results are compatible with calculations based on nucleon-to-pion transition distribution amplitudes (TDAs). These non-perturbative objects are defined as matrix elements of three-quark-light-cone-operators and characterize partonic correlations with a particular emphasis on baryon charge distribution inside a nucleon. Keywords: TDA, Exclusive single pion, Eletroproduction, CLAS
Published: 2018
Full Text: View/download PDF

3. Unitarity constraints on meson electroproduction at backward angles

Author: J. M. Laget
Subjects: Physics, Particle physics, Photon, Meson production, Unitarity, Meson, High Energy Physics::Phenomenology, Nuclear Theory, FOS: Physical sciences, Coupling (probability), Omega, High Energy Physics - Phenomenology, High Energy Physics - Phenomenology (hep-ph), High Energy Physics::Experiment, Nuclear Experiment
Abstract: At large virtuality $Q^2$, the coupling to the $\rho$ meson production channels provides us with a natural explanation of the surprisingly large cross section of the $\omega$, as well as the $\pi^+$, meson electroproduction recently measured at backward angles, without destroying the good agreement between the Regge pole model and the data at the real photon point. Together with elastic re-scattering of the outgoing meson it also provides us with a way to explain why the node, that appears at $u\sim -0.15$ GeV$^2$ at the real photon point, disappears at moderate virtuality $Q^2$. Predictions are given for the electroproduction of the $\pi^0$ meson., Comment: 14 pages, 19 figures. Version in press in Phys. Rev. C. A few slips corrected. Figure 11 frame customized References 10 and 14 corrected
Published: 2021

4. Photoproduction of K+K− meson pairs on the proton

Author: G. Ricco, R. A. Schumacher, K. Mikhailov, L. Bibrzycki, P. Stoler, A. D'Angelo, K. Hicks, H. Hakobyan, Ashot Gasparian, L. Gan, V. Mokeev, A.V. Stavinsky, K. Livingston, D. S. Dale, S. Anefalos Pereira, A. V. Vlassov, D. J. Tedeschi, V. V. Mochalov, K. A. Griffioen, S. Fegan, E. Clinton, Michael Wood, N. Hassall, M. Bellis, K. Hafidi, Michael Vineyard, R. De Vita, S. Stepanyan, C. Bookwalter, P. Nadel-Turonski, M. Kossov, Avraham Klein, T. Mineeva, V. Drozdov, S. Strauch, V. Kuznetsov, Friedrich Klein, D. P. Watts, E. L. Isupov, E. Munevar, H. Egiyan, I. Nakagawa, I. Bedlinskiy, Brian Raue, W. J. Briscoe, Michael L. Williams, A. Kubarovsky, W. Gohn, E. Wolin, Lorenzo Zana, M. Y. Gabrielyan, C. E. Hyde, O. Glamazdin, M. R. Niroula, Z. W. Zhao, S. Niccolai, Y. Prok, D. S. Carman, M. Battaglieri, Barry Ritchie, N. Pivnyuk, I. I. Strakovsky, D. Protopopescu, C. Salgado, E. De Sanctis, M. Garçon, S. Pozdniakov, A. Deur, G. E. Dodge, Martin K. Mayer, G. Rosner, H. Y. Lu, Kei Moriya, C. A. Meyer, M. Osipenko, N. Dashyan, D. I. Sober, F. X. Girod, E. Pasyuk, G. V. Fedotov, S. Tkachenko, Adam P. Szczepaniak, M. S. Saini, I. Niculescu, P. Eugenio, H. Baghdasaryan, K. P. Adhikari, D. P. Weygand, E. Golovatch, M. Taiuti, J. T. Goetz, D. Schott, J. W. Price, C. Djalali, F. Sabatié, V. P. Kubarovsky, O. Pogorelko, W. Kim, P. Collins, M. Anghinolfi, Leonard Lesniak, H. Seraydaryan, J. Zhang, P. Khetarpal, Y. G. Sharabian, C. S. Nepali, M. Ripani, V. Crede, C. Hanretty, J. R. Johnstone, L. Guo, M. Ungaro, S. Park, P. Rossi, K. Joo, M. Guidal, M. Holtrop, A. Daniel, A. I. Ostrovidov, K. Park, Sergey Kuleshov, D. G. Ireland, S. S. Stepanyan, Mark W. Paris, B. Zhao, Volker D. Burkert, A. S. Biselli, S. Dhamija, R. W. Gothe, A. Fradi, M. J. Amaryan, J. Goett, B. McKinnon, D. Branford, S. Pisano, M. Mirazita, S. L. Careccia, J. M. Laget, K. L. Giovanetti, Larry Weinstein, D. Keller, Gerard Gilfoyle, M. Khandaker, M. E. McCracken, Y. Ilieva, D. Sokhan, D. Doughty, A. Teymurazyan, and P. L. Cole
Subjects: Physics, Particle physics, Meson, 010308 nuclear & particles physics, Partial wave analysis, Hadron, Elementary particle, 01 natural sciences, 7. Clean energy, Particle decay, Pion, 0103 physical sciences, High Energy Physics::Experiment, Production (computer science), Nuclear Experiment, 010306 general physics, Nucleon
Abstract: The exclusive reaction $\ensuremath{\gamma}p\ensuremath{\rightarrow}p{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$ was studied in the photon energy range 3.0--3.8 GeV and the momentum transfer range $0.4l\ensuremath{-}tl1.0\text{ }\text{ }{\mathrm{GeV}}^{2}$. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. In this kinematic range, the integrated luminosity was about $20\text{ }\text{ }{\mathrm{pb}}^{\ensuremath{-}1}$. The reaction was isolated by detecting the ${\ensuremath{\pi}}^{+}$ and proton in CLAS, and reconstructing the ${\ensuremath{\pi}}^{\ensuremath{-}}$ via the missing-mass technique. Moments of the di-pion decay angular distributions were derived from the experimental data. Differential cross sections for the $S$, $P$, and $D$-waves, in the ${M}_{{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}}$ mass range 0.4--1.4 GeV, were derived performing a partial wave expansion of the extracted moments. Beside the dominant contribution of the $\ensuremath{\rho}(770)$ meson in the $P$-wave, evidence for the ${f}_{0}(980)$ and the ${f}_{2}(1270)$ mesons was found in the $S$ and $D$-waves, respectively. The differential production cross sections $d\ensuremath{\sigma}/dt$ for individual waves in the mass range of the above-mentioned mesons were extracted. This is the first time the ${f}_{0}(980)$ has been measured in a photoproduction experiment.
Published: 2018

5. Exclusive photoproduction of π0 up to large values of Mandelstam variables s,t, and u with CLAS

Author: S. Adhikari, S. E. Kuhn, M. Hattawy, P. Eugenio, Taya Chetry, E. Golovatch, M. Taiuti, D. Lersch, M. L. Kabir, E. De Sanctis, Carlos A. Salgado, Michael Paolone, S. Procureur, D. I. Sober, D. Protopopescu, G. V. Fedotov, A. Roy, M. Ripani, M. Khachatryan, D. P. Weygand, R. Dupre, M. Battaglieri, Maxime Defurne, M. C. Kunkel, J. Ritman, F. Cao, M. Guidal, Michael Dugger, G. Gavalian, V. P. Kubarovsky, O. Pogorelko, D. I. Glazier, G. Niculescu, P. Lenisa, A. El Alaoui, Barry Ritchie, Iu. Skorodumina, I. Balossino, D. G. Ireland, V. Crede, Frank Klein, I. Bedlinskiy, K. A. Griffioen, R. De Vita, W. Gohn, V. Mokeev, M. Holtrop, L. Elouadrhiri, Y. G. Sharabian, Andreas Klein, Nicholas Zachariou, G. Mbianda Njencheu, W. Phelps, R. A. Schumacher, Dustin Keller, I. I. Strakovsky, A. Filippi, A. Deur, C. Djalali, R. A. Montgomery, K. Hafidi, V. Batourine, H. Avakian, J. A. Tan, L. Lanza, A. D'Angelo, D. P. Watts, D. G. Jenkins, H. Voskanyan, K. Livingston, F. Sabatié, H. Egiyan, M. Khandaker, S. Niccolai, J. Zhang, S. Bültmann, W. J. Briscoe, E. Pasyuk, Alessandro Rizzo, L. El Fassi, J. W. Price, C. E. Hyde, F. X. Girod, L. Guo, M. Ungaro, T. Mineeva, R. G. Fersch, Pawel Nadel-Turonski, P. L. Cole, Z. W. Zhao, K. Hicks, Laura Clark, W. Kim, K. Joo, S. Strauch, G. Charles, B. S. Ishkhanov, O. Cortes, G. Ciullo, E. L. Isupov, J. P. Ball, Y. Prok, D. S. Carman, D. Payette, M. Osipenko, S. Boiarinov, Nikos Sparveris, X. Wei, I. J. D. MacGregor, K. P. Adhikari, A. Kim, E. Voutier, A. Movsisyan, N. Dashyan, H. Hakobyan, S. Stepanyan, L. Barion, M. J. Amaryan, K. L. Giovanetti, Larry Weinstein, G. Khachatryan, S. Schadmand, William Brooks, G. Rosner, S. Ghosh, Y. Ghandilyan, P. V. Degtyarenko, A. Celentano, R. W. Gothe, M. Contalbrigo, C. Munoz Camacho, J. Poudel, B. McKinnon, J. M. Laget, Nicholas M. Harrison, Gerard Gilfoyle, D. Sokhan, A. Fradi, N. Markov, A. I. Ostrovidov, K. Park, G. R. Goldstein, Volker D. Burkert, and A. S. Biselli
Subjects: Quark, Quantum chromodynamics, Physics, Meson, 010308 nuclear & particles physics, Perturbative QCD, Parton, Mandelstam variables, Photon energy, 01 natural sciences, Nuclear physics, 0103 physical sciences, High Energy Physics::Experiment, Sum rule in quantum mechanics, 010306 general physics
Abstract: Exclusive photoproduction cross sections have been measured for the process γ p → p π 0 [ e + e − ( γ ) ] with the Dalitz decay final state using tagged photon energies in the range of E γ = 1.275 – 5.425 GeV. The complete angular distribution of the final state π 0 , for the entire photon energy range up to large values of t and u , has been measured for the first time. The data obtained show that the cross section d σ / d t , at mid to large angles, decreases with energy as s − 6.89 ± 0.26 . This is in agreement with the perturbative QCD quark counting rule prediction of s − 7 . Paradoxically, the size of angular distribution of measured cross sections is greatly underestimated by the QCD-based generalized parton distribution mechanism at highest available invariant energy s = 11 GeV 2 . At the same time, the Regge-exchange-based models for π 0 photoproduction are more consistent with experimental data.
Published: 2018

6. Hard exclusive pion electroproduction at backward angles with CLAS

Author: H. Avakian, B. S. Ishkhanov, K. A. Griffioen, H. Voskanyan, R. Paremuzyan, A. El Alaoui, E. L. Isupov, M. Battaglieri, Nicholas Zachariou, M. Ripani, I. Bedlinskiy, C. Salgado, K. Livingston, M. Hattawy, R. Fersch, S. Stepanyan, M. Ungaro, Nicholas M. Harrison, Gerard Gilfoyle, D. Sokhan, Laura Clark, P. Rossi, Maxime Defurne, Friedrich Klein, P. Eugenio, M. Taiuti, M. L. Kabir, G. Charles, F. Sabatié, A. D'Angelo, David M. Keller, L. Guo, D. Heddle, Chaden Djalali, I. J. D. MacGregor, R. W. Gothe, R. A. Schumacher, W. Kim, O. Pogorelko, F. X. Girod, L. Lanza, C. Munoz Camacho, J. W. Price, C. E. Hyde, C. Hanretty, X. Wei, Y. Prok, M. Khachatryan, K. Hicks, J. Ball, K. Hafidi, M. Osipenko, J. Zhang, D. Protopopescu, Latifa Elouadrhiri, R. De Vita, V. Crede, R. A. Montgomery, Nikolaos Sparveris, E. Voutier, S. Strauch, G. V. Fedotov, Y. G. Sharabian, M. Contalbrigo, Victor Mokeev, B. McKinnon, Taya Chetry, M. Khandaker, Iu. Skorodumina, Andrea Celentano, H. Hakobyan, L. El Fassi, M. Mirazita, J. Poudel, J. M. Laget, S. Niccolai, Z. Akbar, S. Johnston, N. Markov, Kirill M. Semenov-Tian-Shansky, I. I. Strakovsky, G. Niculescu, Y. Ilieva, K. P. Adhikari, A. Deur, E. De Sanctis, S. Adhikari, Y. Ghandilyan, A. Filippi, Michael Paolone, E. Golovatch, R. Dupre, P. L. Cole, D. G. Ireland, S. E. Kuhn, G. Ciullo, G. Khachatryan, D. S. Carman, F. Cao, A. Rizzo, M. Guidal, Volker D. Burkert, W. J. Briscoe, A. S. Biselli, E. Pasyuk, N. Dashyan, William Brooks, G. D. Smith, M. Holtrop, L. Barion, N. A. Baltzell, M. Garçon, H. Egiyan, P. Nadel-Turonski, K. Joo, J. A. Tan, D. G. Jenkins, Bernard Pire, W. Phelps, I. Balossino, K. Park, V. P. Kubarovsky, Institut de Physique Nucléaire d'Orsay (IPNO), 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), Centre de Physique Théorique [Palaiseau] (CPHT), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Interactions Fondamentales en Physique et en Astrophysique (IFPA), Université de Liège, Thomas Jefferson National Accelerator Facility (Jefferson Lab), Istituto Nazionale di Fisica Nucleare, Sezione di Torino (INFN, Sezione di Torino), Istituto Nazionale di Fisica Nucleare (INFN), University of Ca’ Foscari [Venice, Italy], 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, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Clemson University, Old Dominion University [Norfolk] (ODU), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Massachusetts Institute of Technology (MIT), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire d'automatique et de génie des procédés (LAGEP), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École Supérieure de Chimie Physique Électronique de Lyon (CPE)-Centre National de la Recherche Scientifique (CNRS), Politecnico di Torino = Polytechnic of Turin (Polito), Centre d'Etudes Nucléaires de Bordeaux Gradignan (CENBG), Université Sciences et Technologies - Bordeaux 1 (UB)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), School of Mechanical Engineering, University of Birmingham [Birmingham], School of Geography, 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), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Université de Lyon-Université de Lyon-École Supérieure Chimie Physique Électronique de Lyon-Centre National de la Recherche Scientifique (CNRS), and Université Sciences et Technologies - Bordeaux 1-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Quark, Nuclear and High Energy Physics, Electroproduction, Exclusive single pion, transition distribution amplitudes, Particle physics, Meson, Proton, Nuclear Theory, Hadron, Socio-culturale, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], TDA, 01 natural sciences, Resonance (particle physics), CLAS, Eletroproduction, High Energy Physics - Experiment, Settore FIS/04 - Fisica Nucleare e Subnucleare, Nuclear Theory (nucl-th), High Energy Physics - Experiment (hep-ex), Pion, High Energy Physics - Phenomenology (hep-ph), 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, 010308 nuclear & particles physics, lcsh:QC1-999, Baryon, High Energy Physics - Phenomenology, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], High Energy Physics::Experiment, Nucleon, lcsh:Physics
Abstract: We report on the first measurement of cross sections for exclusive deeply virtual pion electroproduction off the proton, $e p \to e^\prime n \pi^+$, above the resonance region at backward pion center-of-mass angles. The $\varphi^*_{\pi}$-dependent cross sections were measured, from which we extracted three combinations of structure functions of the proton. Our results are compatible with calculations based on nucleon-to-pion transition distribution amplitudes (TDAs) and shed new light on nucleon structure., Comment: 7 pages, 6figures
Published: 2017
Full Text: View/download PDF

7. Evidence for the onset of color transparency in ρ0 electroproduction off nuclei

Author: G. Niculescu, S. Tkachenko, R. Dupre, M. Battaglieri, L. Guo, P. Khetarpal, R. De Vita, Paolo Rossi, C. Djalali, G. Ricco, Martin K. Mayer, S. Anefalos Pereira, G. E. Dodge, H. Y. Lu, F. X. Girod, V. Mokeev, Barry Ritchie, P. E. Reimer, B. Vernarsky, J. W. Price, V. Kuznetsov, M. S. Saini, E. Voutier, S. Procureur, F. Sabatié, A. Kim, B. Zhao, I. Niculescu, D. G. Ireland, Friedrich Klein, Brian Raue, V. Crede, W. Tang, M. Ripani, K. A. Griffioen, Michael Vineyard, E. De Sanctis, M. Aghasyan, D. I. Sober, J. T. Goetz, W. Gohn, T. Mineeva, D. Schott, P. Nadel-Turonski, M. Osipenko, Y. Mao, V. P. Kubarovsky, S. Niccolai, C. E. Hyde, S. S. Jawalkar, J. Arrington, P. Stoler, Latifa Elouadrhiri, C. A. Meyer, B. Dey, I. J. D. MacGregor, E. Munevar, B. S. Ishkhanov, S. E. Kuhn, C. Hanretty, K. Hicks, G. V. Fedotov, H. Avakian, E. L. Isupov, K. P. Adhikari, A. Celentano, R. W. Gothe, A. Deur, D. P. Weygand, Elton Smith, George Davey Smith, D. J. Tedeschi, H. Voskanyan, R. A. Schumacher, P. Eugenio, M. Taiuti, M. Anghinolfi, W. J. Briscoe, E. Pasyuk, W. K. Brooks, I. Bedlinskiy, H. Seraydaryan, Lorenzo Zana, S. Park, Y. G. Sharabian, A. D'Angelo, H. Hakobyan, S. Bültmann, X. Zheng, A. I. Ostrovidov, K. Park, M. Contalbrigo, R. J. Holt, C. E. Taylor, S. Stepanyan, C. Salgado, Avraham Klein, L. El Fassi, A. Ni, E. Golovatch, M. Ungaro, J. McAndrew, Z. W. Zhao, Michael Wood, Volker D. Burkert, K. Hafidi, A. S. Biselli, B. McKinnon, D. Branford, M. Mirazita, E. Phelps, J. M. Laget, S. S. Stepanyan, N. Gevorgyan, V. Batourine, N. Markov, D. Keller, Sergey Kuleshov, M. Khandaker, Hovanes Egiyan, M. J. Amaryan, R. Paremuzyan, H. Moutarde, K. L. Giovanetti, Larry Weinstein, Gerard Gilfoyle, D. Doughty, D. Heddle, D. Sokhan, D. Adikaram, M. Guidal, B. Mustapha, M. Holtrop, A. Daniel, Luciano Pappalardo, G. Rosner, A. El Alaoui, Y. Ilieva, Nicholas Zachariou, D. Rimal, B. Moreno, R. Dickson, P. L. Cole, D. Protopopescu, S. Pozdniakov, M. Garçon, S. Chandavar, S. Strauch, D. P. Watts, M. Y. Gabrielyan, D. S. Carman, N. Dashyan, H. Baghdasaryan, S. Fegan, C. Bookwalter, and W. Kim
Subjects: Elastic scattering, Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Hadron, Virtual particle, Electron, 01 natural sciences, Coherence length, Nuclear physics, Color model, Deuterium, Nuclear transparency, 0103 physical sciences, Nuclear Experiment, 010306 general physics
Abstract: We have measured the nuclear transparency of the incoherent diffractive A(e,e′ρ0) process in 12C and 56Fe targets relative to 2H using a 5 GeV electron beam. The nuclear transparency, the ratio of the produced ρ0ʼs on a nucleus relative to deuterium, which is sensitive to ρA interaction, was studied as function of the coherence length (lc), a lifetime of the hadronic fluctuation of the virtual photon, and the four-momentum transfer squared (Q2). While the transparency for both 12C and 56Fe showed no lc dependence, a significant Q2 dependence was measured, which is consistent with calculations that included the color transparency effects.
Published: 2012

8. The extraction of ϕ–N total cross section from d(γ,pK+K−)n

Author: K. Livingston, P. Eugenio, R. Dickson, M. Taiuti, D. Doughty, S. Park, D. Heddle, M. Battaglieri, R. A. Schumacher, S. Stepanyan, Avraham Klein, Michael Vineyard, S. Fegan, K. A. Griffioen, P. Collins, Y. Ilieva, H. Hakobyan, C. E. Hyde, C. Bookwalter, G. E. Dodge, H. Y. Lu, D. G. Ireland, W. Xu, V. Crede, Marco Ripani, F. Sabatié, R. G. Fersch, I. Niculescu, D. J. Tedeschi, M. J. Amaryan, D. Schott, P. L. Cole, Elton Smith, E. L. Isupov, M. E. McCracken, N. Dashyan, I. Bedlinskiy, Gerard Gilfoyle, V. P. Kubarovsky, Michael L. Williams, Tsutomu Mibe, N. Hassall, M. Bellis, S. L. Careccia, D. Sokhan, O. Pogorelko, C. Djalali, Z. W. Zhao, V. Kuznetsov, W. Gohn, A. D'Angelo, H. Baghdasaryan, M. Anghinolfi, Paolo Rossi, K. Hicks, D. Protopopescu, F. X. Girod, Sergey Kuleshov, K. L. Giovanetti, B. McKinnon, I. I. Strakovsky, Lorenzo Zana, S. Pozdniakov, Larry Weinstein, H. Seraydaryan, C. Hanretty, E. Wolin, Friedrich Klein, S. Niccolai, G. Rosner, W. J. Briscoe, Giovanni Ricco, R. Nasseripour, A. Fradi, E. Pasyuk, D. Keller, D. Branford, Brian Raue, J. W. Price, W. Chen, Y. G. Sharabian, J. P. Ball, J. R. Johnstone, L. Guo, C. Salgado, J. M. Laget, A. Deur, Xin Qian, D. S. Carman, Haiyan Gao, M. Ungaro, M. Guidal, M. Khandaker, V. Batourine, S. Tkachenko, S. Pisano, W. K. Brooks, S. Procureur, Martin K. Mayer, K. Joo, B. Zhao, M. S. Saini, A. I. Ostrovidov, K. Park, J. T. Goetz, M. Mirazita, M. Holtrop, A. Daniel, B. Morrison, K. Kramer, Michael Wood, K. Hafidi, Volker D. Burkert, A. S. Biselli, Kei Moriya, C. A. Meyer, J. Zhang, P. Nadel-Turonski, S. S. Jawalkar, E. Golovatch, R. Dupre, G. V. Fedotov, S. Dhamija, R. W. Gothe, S. Strauch, D. P. Watts, K. P. Adhikari, M. Y. Gabrielyan, D. P. Weygand, Barry Ritchie, B. Dey, M. Osipenko, D. Martinez, V. Mokeev, W. Kim, G. Niculescu, P. Khetarpal, C. S. Nepali, R. De Vita, T. Mineeva, S. Anefalos Pereira, E. De Sanctis, D. I. Sober, E. Munevar, B. S. Ishkhanov, and M. R. Niroula
Subjects: Baryon, Nuclear reaction, Physics, Nuclear and High Energy Physics, Cross section (physics), Meson, Deuterium, Proton, Hadron, Analytical chemistry, Atomic physics, Nucleon
Abstract: We report on the first measurement of the differential cross section of ϕ-meson photoproduction for the d ( γ , p K + K − ) n exclusive reaction channel. The experiment was performed using a tagged-photon beam and the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. A combined analysis using data from the d ( γ , p K + K − ) n channel and those from a previous publication on coherent ϕ production on the deuteron has been carried out to extract the ϕ − N total cross section, σ ϕ N . The extracted ϕ − N total cross section favors a value above 20 mb. This value is larger than the value extracted using vector-meson dominance models for ϕ photoproduction on the proton.
Published: 2009

9. Moments of the spin structure functions g1p and g1d for 0.05<Q2<3.0 GeV2

Author: R. A. Schumacher, G. V. O'Rielly, C. D. Keith, Cynthia Marie Hadjidakis, Z. W. Zhao, Chaden Djalali, D. G. Jenkins, Michael Dugger, S. Tkachenko, H. O. Funsten, A. I. Ostrovidov, A. C S Lima, S. Bültmann, L. Morand, M. R. Niroula, T. A. Forest, D. G. Ireland, G. Asryan, Volker D. Burkert, A. S. Biselli, J. Pierce, Elton Smith, M. J. Amaryan, M. MacCormick, O. P. Dzyubak, R. A. Niyazov, I. Hleiqawi, S. L. Careccia, Larry Weinstein, Avraham Klein, E. Golovatch, H. G. Juengst, K. Moriya, Daniel S. Carman, J. Kuhn, Philip L. Cole, S. McAleer, H. Hakobyan, S. Anefalos Pereira, P. D. Rubin, L. Blaszczyk, P. Corvisiero, Y. G. Sharabian, A. Fradi, L. Cheng, G. Audit, A.V. Stavinsky, C. E. Hyde-Wright, F. Sabatié, Nikolay Shvedunov, D. Heddle, P. Stoler, Friedrich Klein, J. P. Cummings, R. De Vita, N. Markov, V. Sapunenko, C. Salgado, Dinko Pocanic, L. Elouadrhiri, N. Kalantarians, S. Stepanyan, K. S. Egiyan, R. C. Minehart, C. A. Meyer, J. Ball, M. Taiuti, S. E. Kuhn, I. I. Strakovsky, M. Bektasoglu, M. Kossov, K. Mikhailov, K.H. Hicks, R. J. Feuerbach, G. V. Fedotov, M. Nozar, A. Deur, I. Popa, V. Crede, J. W. Price, Shifeng Chen, M. Anghinolfi, Laird Kramer, D. P. Watts, H. Egiyan, G. Gavalian, John A. Mueller, L. Casey, B. L. Berman, P. Mattione, B. B. Niczyporuk, G. Rosner, N. Benmouna, N. Pivnyuk, Kwangsoo Kim, J. T. Goetz, M. Mirazita, G. Riccardi, J. R. Calarco, R. A. Miskimen, B. A. Raue, B. McKinnon, W. J. Briscoe, L. M. Qin, R. G. Fersh, P. Eugenio, J. Langheinrich, C. Butuceanu, C. Hanretty, S. S. Stepanyan, E. Pasyuk, S. A. Philips, M. Ripani, G. Ricco, S. A. Morrow, C. Paterson, Y. Ilieva, Michael Vineyard, Victor Mokeev, M. Klusman, B. M. Preedom, D. Branford, P. Collins, B. Moreno, J. R. Johnstone, Lorenzo Zana, J. P. Santoro, Tsutomu Mibe, Gerald Feldman, J. M. Laget, L. Todor, D. Protopopescu, K. L. Giovanetti, S. V. Kuleshov, C. Marchand, S. Pozdniakov, M. Garçon, M. L. Seely, Ji Li, D. J. Tedeschi, G. E. Dodge, H. Y. Lu, J. Lachniet, I. Bedlinskiy, Marco A. Huertas, A. Tkabladze, M. D. Mestayer, E. L. Isupov, P. V. Degtyarenko, D. Rowntree, K. Livingston, Michael L. Williams, M. Holtrop, R. Suleiman, V. Kuznetsov, D. S. Dale, J. Zhang, S. Boiarinov, D. I. Sober, Gerard Gilfoyle, F. X. Girod, G. S. Mutchler, N. A. Baltzell, I. Niculescu, D. Sokhan, J. Salamanca, K. A. Griffioen, D. Lawrence, M. Guillo, N. Guler, R. De Masi, L. El Fassi, J. W C McNabb, Sylvain Bouchigny, H. Denizli, M. Guidal, M. Battaglieri, J. Hardie, S. Strauch, J. D. Kellie, Z. Krahn, R. Nasseripour, S. Barrow, P. Rossi, R. Dickson, N. Baillie, D. Doughty, V. Gyurjyan, R. Bradford, K. Lukashin, B. E. Stokes, G. S. Adams, H. Bagdasaryan, P. Nadel-Turonski, A. V. Skabelin, K. Joo, A. Cazes, S. Procureur, Maryam Moteabbed, Bernhard Mecking, K. V. Dharmawardane, L. Guo, M. Ungaro, D. P. Weygand, E. Wolin, N. Hassall, M. Bellis, D. G. Crabb, J. Yun, D. Cords, P. Bosted, A. Yegneswaran, N. Dashyan, Y. Prok, Barry Ritchie, E. De Sanctis, H. S. Jo, S. Niccolai, R. Fatemi, A. V. Vlassov, P. Coltharp, R. W. Gothe, M. M. Ito, K. Y. Kim, M. Osipenko, K. Beard, L. C. Smith, E. Munevar, Kalvir S. Dhuga, B. S. Ishkhanov, O. Pogorelko, M. Khandaker, B. Zhao, F. W. Hersman, W. Kim, G. Niculescu, N. Gevorgyan, L. C. Dennis, B. E. Bonner, H. Avakian, D. Sharov, S. A. Dytman, W. K. Brooks, K. Park, V. P. Kubarovsky, J. Shaw, Michael Wood, K. Hafidi, and V. S. Serov
Subjects: Physics, Nuclear and High Energy Physics, Chiral perturbation theory, Heavy baryon chiral perturbation theory, Proton, 010308 nuclear & particles physics, Nuclear Theory, Hadron, 01 natural sciences, Baryon, Nuclear physics, Polarizability, 0103 physical sciences, Sum rule in quantum mechanics, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: The spin structure functions g 1 for the proton and the deuteron have been measured over a wide kinematic range in x and Q 2 using 1.6 and 5.7 GeV longitudinally polarized electrons incident upon polarized NH3 and ND3 targets at Jefferson Lab. Scattered electrons were detected in the CEBAF Large Acceptance Spectrometer, for 0.05 Q 2 5 GeV 2 and W 3 GeV . The first moments of g 1 for the proton and deuteron are presented – both have a negative slope at low Q 2 , as predicted by the extended Gerasimov–Drell–Hearn sum rule. The first extraction of the generalized forward spin polarizability of the proton γ 0 p is also reported. This quantity shows strong Q 2 dependence at low Q 2 . Our analysis of the Q 2 evolution of the first moment of g 1 shows agreement in leading order with Heavy Baryon Chiral Perturbation Theory. However, a significant discrepancy is observed between the γ 0 p data and Chiral Perturbation calculations for γ 0 p , even at the lowest Q 2 .
Published: 2009

10. Exclusive ρ0 electroproduction on the proton at CLAS

Author: J. Langheinrich, S. S. Stepanyan, E. Pasyuk, S. A. Philips, N. Dashyan, V. Sapunenko, G. Ricco, Alexei V. Klimenko, N. A. Baltzell, C. Salgado, Dinko Pocanic, Barry Ritchie, H. Denizli, A. V. Skabelin, K. A. Griffioen, B. Zhao, V. Gyurjyan, A. I. Ostrovidov, R. Fatemi, K. Park, S. E. Kuhn, Latifa Elouadrhiri, R. C. Minehart, Kei Moriya, C. A. Meyer, H. G. Juengst, B. E. Stokes, G. S. Adams, G. V. Fedotov, V. P. Kubarovsky, J. Zhang, P. Eugenio, K. P. Adhikari, A. V. Vlassov, D. P. Weygand, G. E. Dodge, H. Y. Lu, M. J. Amaryan, G. V. O'Rielly, S. Niccolai, Z. W. Zhao, V. Mokeev, Y. Ilieva, Ji Li, D. G. Jenkins, C. Tur, Gerard Gilfoyle, Elton Smith, H. Hakobyan, A.V. Stavinsky, J. D. Kellie, M. Guidal, M. MacCormick, I. Hleiqawi, S. L. Careccia, R. De Vita, Friedrich Klein, Brian Raue, P. V. Degtyarenko, M. D. Mestayer, J. P. Didelez, R. Nasseripour, L. Todor, F. W. Hersman, P. Coltharp, E. L. Isupov, J. P. Cummings, W. Gohn, S. A. Morrow, S. McAleer, M. Anghinolfi, P. Nadel-Turonski, D. Sokhan, D. Protopopescu, D. J. Tedeschi, M. Holtrop, Michael L. Williams, P. Collins, K. L. Giovanetti, I. Niculescu, F. X. Girod, L. Blaszczyk, B. Carnahan, James Mueller, D. Lawrence, R. G. Fersch, R. A. Miskimen, B. McKinnon, S. Pozdniakov, M. Garçon, J. J. Melone, M. M. Ito, S. Boiarinov, Larry Weinstein, L. Zana, P. D. Rubin, R. De Masi, D. Keller, I. Bedlinskiy, B. M. Preedom, S. Anefalos Pereira, D. Schott, Y. G. Sharabian, R. A. Schumacher, P. L. Cole, M. Yurov, M. Taiuti, S. Mehrabyan, D. Branford, L. C. Smith, E. Munevar, G. S. Mutchler, B. S. Ishkhanov, Michael Wood, K. Hafidi, L. Graham, M. Kossov, M. E. McCracken, C. I O Gordon, J. M. Laget, V. Kuznetsov, J. Kuhn, E. Hourany, M. Khandaker, V. S. Serov, L. C. Dennis, B. E. Bonner, J. W. Price, Tsutomu Mibe, S. Bültmann, G. Audit, Shifeng Chen, C. Bookwalter, N. Gevorgyan, M. Osipenko, C. E. Hyde-Wright, J. P. Santoro, H. S. Jo, H. Avakian, L. Morand, I. Popa, D. Sharov, T. A. Forest, G. Riccardi, M. R. Niroula, E. De Sanctis, O. Pogorelko, S. Stepanyan, P. Mattione, C. Butuceanu, M. S. Saini, D. Doughty, J. Pierce, M. Ripani, B. L. Berman, Avraham Klein, L. M. Qin, M. Aghasyan, E. Wolin, Sergey Kuleshov, W. J. Briscoe, D. Heddle, J. T. Goetz, D. I. Sober, Kalvir S. Dhuga, M. Bektasoglu, S. A. Dytman, S. Dhamija, M. Nozar, E. Polli, M. Mirazita, C. Paterson, J. P. Ball, R. W. Gothe, Y. Prok, B. Moreno, W. Kim, J. Hardie, Hall Crannell, D. S. Carman, K. Livingston, G. Rosner, C. Marchand, G. Niculescu, D. S. Dale, N. Baillie, S. Park, Sylvain Bouchigny, J. Lachniet, A. Tkabladze, D. G. Crabb, R. Dickson, Michael Vineyard, D. G. Ireland, V. Crede, J. R. Calarco, P. Khetarpal, N. Guler, J. Salamanca, L. El Fassi, J. W C McNabb, S. Barrow, P. Rossi, L. Casey, H. Bagdasaryan, Volker D. Burkert, A. S. Biselli, B. B. Niczyporuk, N. Pivnyuk, P. Stoler, C. Hanretty, Laird Kramer, J. R. Johnstone, L. Guo, M. Ungaro, A. Fradi, K. Joo, D. Cords, N. Markov, A. Yegneswaran, K. Hicks, M. Battaglieri, R. Bradford, K. S. Egiyan, A. Cazes, S. Procureur, Maryam Moteabbed, Bernhard Mecking, K. V. Dharmawardane, N. Hassall, M. Bellis, K. Mikhailov, G. Asryan, O. P. Dzyubak, R. A. Niyazov, P. Corvisiero, S. Strauch, D. P. Watts, H. Egiyan, I. I. Strakovsky, A. Deur, W. K. Brooks, R. J. Feuerbach, Cynthia Marie Hadjidakis, M. Guillo, Chaden Djalali, Michael Dugger, L. Cheng, F. Sabatié, Nikolay Shvedunov, N. Kalantarians, G. Gavalian, S. Tkachenko, and N. Benmouna
Subjects: Quark, Physics, REPRESENTATION, Nuclear and High Energy Physics, Particle physics, Valence (chemistry), Proton, Hadron, Parton, VECTOR-MESON ELECTROPRODUCTION, Approx, PHOTONS, QCD, EVOLUTION, High Energy Physics - Experiment, Regge theory, Nuclear physics, Scattering amplitude, GENERALIZED PARTON DISTRIBUTIONS, VIRTUAL COMPTON-SCATTERING, VECTOR-MESON ELECTROPRODUCTION, LARGE MOMENTUM-TRANSFER, DIFFRACTIVE PRODUCTION, PHOTOPRODUCTION, PHOTONS, QCD, REPRESENTATION, EVOLUTION, LARGE MOMENTUM-TRANSFER, GENERALIZED PARTON DISTRIBUTIONS, DIFFRACTIVE PRODUCTION, PHOTOPRODUCTION, Nuclear Experiment, VIRTUAL COMPTON-SCATTERING
Abstract: The $e p\to e^\prime p \rho^0$ reaction has been measured, using the 5.754 GeV electron beam of Jefferson Lab and the CLAS detector. This represents the largest ever set of data for this reaction in the valence region. Integrated and differential cross sections are presented. The $W$, $Q^2$ and $t$ dependences of the cross section are compared to theoretical calculations based on $t$-channel meson-exchange Regge theory on the one hand and on quark handbag diagrams related to Generalized Parton Distributions (GPDs) on the other hand. The Regge approach can describe at the $\approx$ 30% level most of the features of the present data while the two GPD calculations that are presented in this article which succesfully reproduce the high energy data strongly underestimate the present data. The question is then raised whether this discrepancy originates from an incomplete or inexact way of modelling the GPDs or the associated hard scattering amplitude or whether the GPD formalism is simply inapplicable in this region due to higher-twists contributions, incalculable at present., Comment: 29 pages, 29 figures
Published: 2008

11. DEEPLY VIRTUAL AND EXCLUSIVE PRODUCTION OF THE OMEGA MESON

Author: S. Morrow, F. Sabatie, L. Morand, M. Garcon, J.-M. Laget, and D. Dore
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Meson, Hadron, Astronomy and Astrophysics, Parton, Elementary particle, Omega, Atomic and Molecular Physics, and Optics, Baryon, Nuclear physics, Nucleon, Boson
Abstract: Exclusive ω electroproduction off the proton was measured at the highest possible four-momentum transfer with the (close to) 6 GeV beam now available at CEBAF. Cross sections are presented, together with an analysis of the ω spin density matrix elements. Indications are that π0 exchange in the t-channel (or rather the exchange of the corresponding saturating Regge trajectory) seems to dominate the process γ*p→ωp, even for photon virtuality Q2 as large as 5 GeV2. Contributions of the handbag type, related to Generalized Parton Distributions in the nucleon, are therefore difficult to extract from this particular process.
Published: 2005

12. The photoproduction of vector mesons

Author: J.-M. Laget
Subjects: Quark, Physics, Nuclear and High Energy Physics, Particle physics, High energy, Meson, Scattering, High Energy Physics::Lattice, Nuclear Theory, High Energy Physics::Phenomenology, Hadron, FOS: Physical sciences, High Energy Physics - Phenomenology, symbols.namesake, High Energy Physics - Phenomenology (hep-ph), symbols, High Energy Physics::Experiment, van der Waals force, Nuclear Experiment, Nucleon, Beam (structure)
Abstract: At high energy, the photoproduction or electroproduction of Vector Mesons allow to prepare a beam of quark-antiquark pairs of a given flavor. At high momentum transfer, the study of the scattering of these pairs on a nucleon opens up an original window on the quark-gluon structure of hadronic matter, which may eventually shed light on its gluonic content, on correlations between quarks and on the van der Walls part of the interaction between hadrons., Comment: 10 pages; 9 figures; Invited talk at the "Third International Conference on Perspectives in Hadronic Physics", Trieste (Italy), 7--11 May 2001; Nucl. Phys. A, in press
Published: 2002

13. Theep→e′pηReaction at and above theS11(1535)Baryon Resonance

Author: M. J. Amaryan, M. Taiuti, S. K. Matthews, J. Ficenec, Gyurjyan, W. Kim, A. Longhi, R. A. Schumacher, B. E. Bonner, L. Elouadrhiri, A. P. Freyberger, R. Magahiz, Robert E. Welsh, S. Dytman, S. Whisnant, B. M. Preedom, Federico Ronchetti, R. J. Feuerbach, K. L. Giovanetti, B. Asavapibhop, Michael Dugger, Shalev Gilad, De Sanctis E, A. V. Vlassov, G. Ricco, J. R. Kane, H. Avakian, Philip L. Cole, J. P. Cummings, G. S. Adams, Larry Weinstein, R. A. Miskimen, K. Joo, J. Shaw, R. W. Major, Moshe Gai, M. Kossov, W. J. Briscoe, D. Rowntree, D. Doughty, K. Beard, W. K. Brooks, Friedrich Klein, R. S. Hicks, Brian Raue, Kevin Fissum, Kalvir S. Dhuga, Barry Ritchie, A. Coleman, K. A. Griffioen, M. M. Ito, G. Riccardi, L. M. Qin, J. J. Manak, M. Mirazita, J. M. Laget, C. E. Hyde-Wright, J. W C McNabb, M. S. Ohandjanyan, D. Heddle, C. Salgado, H. R. Weller, Roy Thompson, Curtis Smith, D. P. Weygand, Herbert O. Funsten, S. A. Philips, Patrick Girard, Y. Kuang, H. Egiyan, M. Witkowski, Bernhard Mecking, Mestayer, A. J. Sarty, Jing Zhao, S. Stepanyan, De Vita R, D. G. Jenkins, C. Djalali, Z. L. Zhou, M. Lucas, Airton Deppman, D. I. Sober, A. Shafi, D. Hancock, Avraham Klein, Leskin Ga, M. Battaglieri, S. McAleer, William Bertozzi, E. Polli, E. Anciant, L. Farhi, G. E. Dodge, Daniel S. Carman, V. B. Gavrilov, O. Pogorelko, A. K. Opper, G. Audit, J. W. Price, M. Khandaker, E. Wolin, P. V. Degtyarenko, Y. Patois, Gerard Gilfoyle, Dinko Pocanic, L.C. Dennis, K. Loukachine, N. Pivnyuk, M. Bektasoglu, S. E. Kuhn, S. M. Shuvalov, D. Lawrence, M. Eckhause, J. Napolitano, M. Ripani, M. Guillo, Jochen Heisenberg, Y. V. Efremenko, Volker D. Burkert, M. Sanzone, J. Connelly, Donal Day, M. Sargsyan, G. A. Peterson, M. Guidal, A. V. Skabelin, J. Yun, D. Cords, A. Yegneswaran, A. S. Biselli, Elton Smith, S. Barrow, M. Holtrop, Thomas E. Smith, G. S. Mutchler, M. Anghinolfi, Hall Crannell, D. G. Crabb, James Mueller, S. Taylor, P. D. Rubin, G. Capitani, F. Roudot, D. J. Tedeschi, Y. G. Sharabian, M. Spraker, Sapunenko, R. C. Minehart, M. Klusman, Nicola Bianchi, S. Boiarinov, C. A. Meyer, J. S. McCarthy, B. Carnahan, Thierry Auger, A. R. Reolon, Michael Vineyard, C. Marchand, P. Rossi, P. Dragovitsch, F. W. Hersman, R. A. Demirchyan, T. Y. Tung, J. Hardie, K. Y. Kim, Muccifora, R. A. Niyazov, John T. O'Brien, P. Corvisiero, K. S. Egiyan, Calarco, P. Stoler, and K. Hicks
Subjects: Baryon, Physics, Nuclear physics, Particle physics, Photon, Amplitude, Angular distribution, Meson, Momentum transfer, General Physics and Astronomy, Resonance, Invariant (physics), Nuclear Experiment
Abstract: New cross sections for the reaction e p-->e p eta are reported for total center of mass energy W = 1.5--1.86 GeV and invariant momentum transfer Q2 = 0.25--1.5 (GeV/c)(2). This large kinematic range allows extraction of important new information about response functions, photocouplings, and eta N coupling strengths of baryon resonances. Newly observed structure at W approximately 1.65 GeV is shown to come from interference between S and P waves and can be interpreted with known resonances. Improved values are derived for the photon coupling amplitude for the S11(1535) resonance.
Published: 2001

14. Photoproduction of vector mesons at large momentum transfer

Author: J. M. Laget
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Pomeron, Meson, Transfer (computing), High Energy Physics::Phenomenology, High Energy Physics::Experiment, Impact parameter, Nuclear Experiment, Communication channel, Gluon
Abstract: At forward angles, the cross-sections of photoproduction of vector mesons ($\rho$, $\omega$, and $\phi$) are well accounted for by the exchange of the Pomeron at high energies, while contributions of $t$ channel exchange of Reggeons are significant at low energies. At large angles, the impact parameter becomes small enough to prevent their constituents to build up the exchanged Reggeons or Pomeron. Two gluon exchange appears to dominate above $-t\simeq 1$ GeV$^2$, especially in the $\phi$ channel.
Published: 2000

15. Regge description of charged pseudoscalar meson electroproduction above the resonance region

Author: M. Guidal, Marc Vanderhaeghen, and J. M. Laget
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Meson production, Meson, High Energy Physics::Lattice, High Energy Physics::Phenomenology, Nuclear Theory, Invariant (physics), Pseudoscalar meson, Nuclear physics, Pion, Yield ratio, High Energy Physics::Experiment, Nuclear Experiment
Abstract: A gauge invariant model based on $\ensuremath{\pi}$ and $\ensuremath{\rho}$ Regge trajectory exchanges provides a successful and economical description of the forward charged pion electroproduction reactions above the resonance region. Its sensitivity to the meson form factors is investigated in kinematics where the pion electromagnetic form factor will be extracted at high ${Q}^{2}$ at TJNAF. An extension to ${K}^{+}$ electroproduction is presented.
Published: 1998

16. Perspectives in hadron and quark dynamics

Author: F. Kunne, D.O. Riska, Claude Amsler, J. M. Laget, B. Frois, Frank Close, D. von Harrach, Volker Metag, E. De Sanctis, T. Bressani, and Piet J. Mulders
Subjects: Quark, Physics, Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, 0103 physical sciences, Hadron, Dynamics (mechanics), 010306 general physics, 01 natural sciences
Published: 1997

17. Deep exclusive π+ electroproduction off the proton at CLAS

Author: K. Park, M. Guidal, R. W. Gothe, J. M. Laget, M. Garçon, K. P. Adhikari, M. Aghasyan, M. J. Amaryan, M. Anghinolfi, H. Avakian, H. Baghdasaryan, J. Ball, N. A. Baltzell, M. Battaglieri, I. Bedlinsky, R. P. Bennett, A. S. Biselli, C. Bookwalter, S. Boiarinov, W. J. Briscoe, W. K. Brooks, V. D. Burkert, D. S. Carman, A. Celentano, S. Chandavar, G. Charles, M. Contalbrigo, V. Crede, A. D’Angelo, A. Daniel, N. Dashyan, R. De Vita, E. De Sanctis, A. Deur, C. Djalali, G. E. Dodge, D. Doughty, R. Dupre, H. Egiyan, A. El Alaoui, L. El Fassi, P. Eugenio, G. Fedotov, S. Fegan, J. A. Fleming, T. A. Forest, A. Fradi, N. Gevorgyan, G. P. Gilfoyle, K. L. Giovanetti, F. X. Girod, W. Gohn, E. Golovatch, L. Graham, K. A. Griffioen, B. Guegan, L. Guo, K. Hafidi, H. Hakobyan, C. Hanretty, D. Heddle, K. Hicks, D. Ho, M. Holtrop, Y. Ilieva, D. G. Ireland, B. S. Ishkhanov, D. Jenkins, H. S. Jo, D. Keller, M. Khandaker, P. Khetarpal, A. Kim, W. Kim, F. J. Klein, S. Koirala, A. Kubarovsky, V. Kubarovsky, S. E. Kuhn, S. V. Kuleshov, K. Livingston, H. Y. Lu, I. J. D. MacGregor, Y. Mao, N. Markov, D. Martinez, M. Mayer, B. McKinnon, C. A. Meyer, T. Mineeva, M. Mirazita, V. Mokeev, H. Moutarde, E. Munevar, C. Munoz Camacho, P. Nadel-Turonski, C. S. Nepali, S. Niccolai, G. Niculescu, I. Niculescu, M. Osipenko, A. I. Ostrovidov, L. L. Pappalardo, R. Paremuzyan, S. Park, E. Pasyuk, S. Anefalos Pereira, E. Phelps, S. Pisano, O. Pogorelko, S. Pozdniakov, J. W. Price, S. Procureur, D. Protopopescu, A. J. R. Puckett, B. A. Raue, G. Ricco, D. Rimal, M. Ripani, G. Rosner, P. Rossi, F. Sabatié, M. S. Saini, C. Salgado, D. Schott, R. A. Schumacher, E. Seder, H. Seraydaryan, Y. G. Sharabian, E. S. Smith, G. D. Smith, D. I. Sober, D. Sokhan, S. S. Stepanyan, P. Stoler, I. I. Strakovsky, S. Strauch, M. Taiuti, W. Tang, C. E. Taylor, Ye Tian, S. Tkachenko, A. Trivedi, M. Ungaro, B. Vernarsky, H. Voskanyan, E. Voutier, N. K. Walford, D. P. Watts, L. B. Weinstein, D. P. Weygand, M. H. Wood, N. Zachariou, J. Zhang, Z. W. Zhao, I. Zonta, 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, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), CLAS, 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), and 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)
Subjects: Particle physics, Nuclear and High Energy Physics, Hadron, Theoretical models, Parton, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Settore FIS/04 - Fisica Nucleare e Subnucleare, SCALING LAWS, 0103 physical sciences, VIRTUAL COMPTON-SCATTERING, PION FORM-FACTOR, CROSS-SECTION, HIGH-ENERGIES, PHOTOPRODUCTION, DEUTERON, MESONS, PHOTODISINTEGRATION, MOMENTUM, 010306 general physics, Nuclear Experiment, Physics, 010308 nuclear & particles physics, Scattering, Phenomenology (particle physics)
Abstract: The exclusive electroproduction of $\pi^+$ above the resonance region was studied using the $\rm{CEBAF}$ Large Acceptance Spectrometer ($\rm{CLAS}$) at Jefferson Laboratory by scattering a 6 GeV continuous electron beam off a hydrogen target. The large acceptance and good resolution of $\rm{CLAS}$, together with the high luminosity, allowed us to measure the cross section for the $\gamma^* p \to n \pi^+$ process in 140 ($Q^2$, $x_B$, $t$) bins: $0.16, Comment: 18pages, 21figures,2tables
Published: 2013

18. Exclusive photo- and electroproduction of vector mesons at large momentum transfer

Author: R. Mendez-Galain and J.-M. Laget
Subjects: Quark, Physics, Nuclear and High Energy Physics, Particle physics, Field (physics), Meson, High Energy Physics::Lattice, Nuclear Theory, High Energy Physics::Phenomenology, Hadron, Momentum transfer, Nuclear matter, Nuclear physics, Pomeron, High Energy Physics::Experiment, Nuclear Experiment, Ground state
Abstract: Two-gluon-exchange mechanisms are expected to govern exclusive photo- and electro-production of vector mesons at large momentum transfer. While quark-interchange mechanisms may compete, at least at low energies, in the light-quark sector, they are strongly suppressed in the heavy-quark sector. Phi-meson production appears to be a promising way to study these two-gluon-exchange mechanisms. On the one hand, they appear to be a good candidate to explain the hard part of the pomeron. On the other hand, they open up an almost virgin field: the study of quark correlations in hadronic matter. A possible application would be the study of hidden color components in the wave function of the ground state of few-nucleon systems.
Published: 1995

19. Comparison of forward and backwardpppair knockout in3He(e,e′pp)n

Author: V. Crede, S. Strauch, M. Contalbrigo, M. Paolone, H. Egiyan, M. J. Amaryan, S. Niccolai, M. Taiuti, N. Dashyan, D. G. Jenkins, N. A. Saylor, S. Procureur, S. V. Kuleshov, Michael Wood, D. Sokan, B. S. Ishkhanov, K. Hafidi, W. Tang, M. Y. Gabrielyan, K. L. Giovanetti, B. McKinnon, H. S. Jo, K. A. Griffioen, M. Osipenko, Larry Weinstein, A. D'Angelo, A. Celentano, R. W. Gothe, E. Voutier, E. De Sanctis, D. Doughty, P. Khetarpal, G. Charles, S. Pisano, F. X. Girod, H. Baghdasaryan, J. Ball, A. El Alaoui, S. Chandavar, M. Aghasyan, L. El Fassi, V. Mokeev, Lorenzo Zana, M. Mirazita, J. M. Laget, S. Park, H. Moutarde, S. S. Stepanyan, K. Park, V. P. Kubarovsky, W. Gohn, D. Rimal, P. Rossi, D. I. Sober, D. G. Ireland, S. Tkachenko, H. Voskanyan, R. Dupre, N. Gevorgyan, K. Joo, M. Battaglieri, R. A. Schumacher, Volker D. Burkert, A. S. Biselli, Latifa Elouadrhiri, A. Kim, B. Zhao, W. Kim, A. Kubarovsky, G. Rosner, G. V. Fedotov, G. Niculescu, P. L. Cole, W. K. Brooks, R. Paremuzyan, W. J. Briscoe, M. Guidal, S. Pozdniakov, K. P. Adhikari, D. S. Carman, M. Khandaker, S. Stepanyan, E. Munevar, Gerard Gilfoyle, R. De Vita, G. E. Dodge, H. Y. Lu, N. D. Kvaltine, A. Daniel, I. Niculescu, Luciano Pappalardo, I. J. D. MacGregor, D. Schott, K. Hicks, C. E. Hyde, G. Ricco, Brian Raue, B. Guegan, M. Ripani, Chaden Djalali, S. E. Kuhn, Elton Smith, M. Anghinolfi, H. Seraydaryan, and M. S. Saini
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Momentum (technical analysis), Proton, 010308 nuclear & particles physics, Nuclear Theory, Momentum transfer, EMC effect, Few-body systems, 01 natural sciences, Nuclear physics, 0103 physical sciences, Nuclear force, Neutron, Nuclear Experiment, 010306 general physics, Wave function
Abstract: Measuring nucleon-nucleon Short Range Correlations (SRC) has been a goal of the nuclear physics community for many years. They are an important part of the nuclear wavefunction, accounting for almost all of the high-momentum strength. They are closely related to the EMC effect. While their overall probability has been measured, measuring their momentum distributions is more difficult. In order to determine the best configuration for studying SRC momentum distributions, we measured the 3He(e,e'pp)n reaction, looking at events with high momentum protons (pp > 0.35 GeV/c) and a low momentum neutron (pn < 0.2 GeV/c). We examined two angular configurations: either both protons emitted forward or one proton emitted forward and one backward (with respect to the momentum transfer, →q). Thus, the measured relative momentum distribution of the events with one forward and one backward proton was much closer to the calculated initial-state pp relative momentum distribution, indicating that this is the preferred configuration for measuring SRC.
Published: 2012

20. Exclusive Photodisintegration ofHe3with Polarized Photons

Author: G. Giordano, S.T. Thornton, R. A. Lindgren, G. Audit, M. A. Duval, G. S. Adams, O. C. Kistner, H. Baghaei, P. Stoler, E. J. Winhold, Murray Moinester, P. K. Teng, W. K. Mize, C. Ruth, C. Schaerf, D. J. Tedeschi, C. S. Whisnant, L. C. Smith, L. Miceli, R. M. Sealock, K. Vaziri, G. Matone, W. B. Clayton, S. Hoblit, A. M. Sandorfi, C. E. Thorn, J. M. Laget, A. Caracappa, and A. D'Angelo
Subjects: Nuclear reaction, Physics, Nuclear physics, Photon, Photodisintegration, Nuclear Theory, Hadron, General Physics and Astronomy, Elementary particle, Neutron, Nuclear Experiment, Absorption (electromagnetic radiation), Nucleon
Abstract: The first measurement of exclusive photodisintegration of He-3 with polarized photons is reported. Cross sections and asymmetries for He-3(gamma over arrow pointing right, pn)p and He-3(gamma over arrow pointing right, pp)n at 235 less-than-or-equal-to E(gamma) less-than-or-equal-to 305 MeV are compared to a theoretical calculation which includes one-, two-, and three-nucleon photon absorption. Two-nucleon absorption dominates the pn data, but is suppressed in the pp data. The pp data require the inclusion of three-nucleon absorption to describe the cross section and beam asymmetry over all momenta.
Published: 1994

21. Study of the deuteron structure in quasi-elastic breakup reaction pd → ppn at 1 GeV

Author: S.I. Manayenkov, S. L. Belostotski, N.P. Aleshin, O.G. Grebenyuk, O.V. Miklukho, V.N. Nikulin, Vladimir Nelyubin, A. Boudard, L.M. Kochenda, J.-M. Laget, V.A. Gordeev, V.I. Lasarev, O.E. Prokofiev, V. V. Vikhrov, V. V. Sulimov, and E.N. Komarov
Subjects: Physics, Nuclear reaction, Nuclear and High Energy Physics, Scattering, Nuclear Theory, Hadron, Nuclear structure, Elementary particle, Nuclear physics, Baryon, Neutron, Atomic physics, Nuclear Experiment, Nucleon
Abstract: Quasi-elastic deuteron break-up reactions pd → pp ( n ) and pd → pn ( p ) have been studied in complete kinematics at 1 GeV. Two outgoing nucleons were detected in coincidence by means of a two-arm spectrometer. After a correction to the impulse approximation for double scattering and Δ-excitation effects, a good agreement with data is found using a momentum distribution of nucleons in the deuteron computed from nucleon-nucleon potentials. This good agreement is obtained up to 0.5 GeV/ c .
Published: 1994

22. First measurement of the reactionHe3(γ→,p)Xwith polarized photons

Author: J. M. Laget, D. J. Tedeschi, Murray Moinester, L. C. Smith, R. M. Sealock, K. Vaziri, A. M. Sandorfi, O. C. Kistner, M. A. Duval, P. Stoler, W. B. Clayton, C. S. Whisnant, E. J. Winhold, S. Hoblit, L. Miceli, S.T. Thornton, R. A. Lindgren, C. Ruth, G. Matone, H. Baghaei, W. K. Mize, C. Schaerf, P. K. Teng, C. E. Thorn, A. Caracappa, A. D'Angelo, G. S. Adams, and G. Giordano
Subjects: Nuclear reaction, Physics, Photon, Proton, Computer Science::Information Retrieval, media_common.quotation_subject, Nuclear Theory, Hadron, General Physics and Astronomy, Elementary particle, Asymmetry, Baryon, Atomic physics, Nuclear Experiment, Nucleon, media_common
Abstract: The first measurement of the reaction [sup 3]He([rvec [gamma]],[ital p])[ital X] using linearly polarized photons is reported. Cross sections and beam-polarization asymmetries for [theta][sub [ital p]][sup lab]=60[degree]--100[degree] and [ital E][sub [gamma]]=195--304 MeV are compared with a microscopic calculation which includes one-, two-, and three-nucleon absorption mechanisms. One- and two-nucleon absorption alone fails to describe the data at low proton momenta. The inclusion of three-nucleon absorption significantly improves the comparison with the measured cross sections. However, some features of the asymmetry distributions are not explained.
Published: 1994

23. Probing the high momentum component of the deuteron at high Q^2

Author: E. Piasetzky, D. Hayes, A. Klein, M. B. Epstein, X. Jiang, J. P. Chen, B. Reitz, R. A. Lindgren, J. J. LeRose, M. Roedelbronn, Ronald Ransome, O. Gayou, Bogdan Wojtsekhowski, G. Batigne, J. M. Finn, D. J. Margaziotis, John Arrington, Olfred Hansen, W. U. Boeglin, Brian Raue, J. H. Mitchell, L. J. Kaufman, Rakhsha Nasseripour, R. Roché, J. M. Laget, S. Kox, C. E. Hyde, M. Zeier, J. Reinhold, C. W. de Jager, F. Garibaldi, A. Camsonne, Arijit Saha, Maryam Moteabbed, Karl Slifer, Larry Weinstein, K. A. Aniol, P. Monaghan, S. Frullani, Kent Paschke, Vincent Sulkosky, W. Hinton, P. E. Ulmer, Pete Markowitz, I. A. Qattan, Z. E. Meziani, J. S. Real, P. Moussiegt, H. F. Ibrahim, P. Bosted, G. Kumbartzki, C. F. Perdrisat, G. Chang, R. Michaels, P. Ambrozewicz, E. Voutier, V. A. Punjabi, Christophe Furget, A. Deur, Laird Kramer, P. Solvignon, L. Coman, G. Quéméner, B. Milbrath, K. McCormick, Seonho Choi, Ronald Gilman, Douglas Higinbotham, M. K. Jones, Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), and HALL A
Subjects: Nuclear reaction, Particle physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Nuclear Theory, Hadron, FOS: Physical sciences, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, Nuclear Theory (nucl-th), Nuclear physics, Momentum, Cross section (physics), Recoil, 0103 physical sciences, Neutron, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, 010308 nuclear & particles physics, Momentum transfer, Nucleon
Abstract: The d(e,e'p) cross section at a momentum transfer of 3.5 (GeV/c)^2 was measured over a kinematical range that made it possible to study this reaction for a set of fixed missing momenta as a function of the neutron recoil angle theta_nq and to extract missing momentum distributions for fixed values of theta_nq up to 0.55 GeV/c. In the region of 35 (deg), 5 pages, 2 figures
Published: 2011

24. Near-threshold photoproduction of ϕ mesons from deuterium

Author: V. Mokeev, E. Seder, S. Fegan, A. El Alaoui, Y. Ilieva, D. G. Ireland, Z. W. Zhao, V. Crede, M. E. McCracken, Kei Moriya, C. A. Meyer, Barry Ritchie, Tsutomu Mibe, Friedrich Klein, K. P. Adhikari, D. P. Weygand, F. Sabatié, Nicholas Zachariou, S. Pisano, C. Bookwalter, W. Kim, E. De Sanctis, R. A. Schumacher, A. Kim, R. Paremuzyan, George Davey Smith, F. X. Girod, K. A. Griffioen, S. Dhamija, P. Eugenio, B. Moreno, L. Graham, Xin Qian, D. I. Sober, M. Taiuti, S. Strauch, J. Zhang, R. W. Gothe, G. Rosner, K. Livingston, A. D'Angelo, S. Stepanyan, Avraham Klein, A. Ni, M. Ripani, H. Egiyan, S. Tkachenko, N. Dashyan, Gerard Gilfoyle, J. W. Price, I. Niculescu, P. Collins, G. Ricco, S. Park, C. E. Taylor, N. Hassall, M. Bellis, D. Sokhan, M. Osipenko, Michael Vineyard, Sergey Kuleshov, D. Schott, P. Rossi, R. De Vita, D. Martinez, B. McKinnon, A. I. Ostrovidov, K. Park, T. Mineeva, D. Protopopescu, C. Hanretty, Lorenzo Zana, S. Pozdniakov, P. L. Cole, S. Anefalos Pereira, E. Munevar, S. S. Stepanyan, H. S. Jo, M. Y. Gabrielyan, Wei-Jiang Xu, Volker D. Burkert, L. Guo, M. Ungaro, B. Zhao, C. Salgado, A. S. Biselli, M. R. Niroula, D. Branford, M. Guidal, S. S. Jawalkar, J. P. Ball, D. S. Carman, P. Khetarpal, M. Mirazita, M. Holtrop, Haiyan Gao, A. Daniel, J. M. Laget, K. Kramer, K. Joo, N. Gevorgyan, R. Dupre, M. Battaglieri, H. Moutarde, V. Batourine, B. Vernarsky, K. Mikhailov, P. Stoler, B. Dey, K. Hicks, P. Konczykowski, S. Procureur, Yujie Qiang, Martin K. Mayer, M. S. Saini, J. T. Goetz, Elton Smith, M. Anghinolfi, H. Seraydaryan, Y. G. Sharabian, I. I. Strakovsky, A. Deur, W. K. Brooks, P. Nadel-Turonski, E. Voutier, W. Gohn, C. Djalali, B. Morrison, J. McAndrew, Michael Wood, K. Hafidi, D. Doughty, D. Keller, W. J. Briscoe, W. Chen, M. Khandaker, M. J. Amaryan, V. P. Kubarovsky, O. Pogorelko, S. L. Careccia, K. L. Giovanetti, Larry Weinstein, V. Kuznetsov, S. Niccolai, H. Hakobyan, D. J. Tedeschi, I. Bedlinskiy, 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, Institut de Physique Nucléaire d'Orsay (IPNO), 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), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS), CLAS, 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), 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), Massachusetts Institute of Technology. Department of Physics, and Xu, W.
Subjects: Nuclear and High Energy Physics, Photon, Proton, Meson, Hadron, Nuclear Theory, FOS: Physical sciences, Photon energy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], phi meson photoproduction, 01 natural sciences, Settore FIS/04 - Fisica Nucleare e Subnucleare, Nuclear physics, Near threshold, 0103 physical sciences, Deuteron, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Quasi free, Physics, 010308 nuclear & particles physics, Momentum transfer, NUCLEAR-BOUND QUARKONIUM, Deuterium, High Energy Physics::Experiment, Nucleon
Abstract: We report the first, kinematically-complete measurement of the differential cross section of ϕ-meson photoproduction from deuterium near the production threshold for a proton using the CLAS detector and a tagged-photon beam in Hall B at Jefferson Lab. The measurement was carried out by a triple coincidence detection of a proton, K[superscript +] and K[superscript −] near the theoretical production threshold of 1.57 GeV. The extracted differential cross sections dσ/dt for the initial photon energy range of 1.65–1.75 GeV are consistent with predictions based on a quasifree mechanism. Our finding is different from recent LEPS results on ϕ-meson photoproduction from deuterium in a similar incident photon energy range, but in a different momentum transfer region., United States. Dept. of Energy, National Science Foundation (U.S.)
Published: 2011

25. The reaction 3He(γ, pp)n at low neutron recoil momentum

Author: J. Martino, G. Audit, A. Braghieri, X. H. Phan, D. Goutte, W. B. Clayton, P. Bricault, J. M. Laget, N. d'Hose, P. Pedroni, G. S. Adams, and P. Stoler
Subjects: Physics, Nuclear and High Energy Physics, Photon, Proton, Scattering, Nuclear Theory, Momentum, Recoil, Physics::Accelerator Physics, Neutron, Center of mass, Proton emission, Atomic physics, Nuclear Experiment
Abstract: The reaction 3 He( γ , p ) n was measured at the ALS-Saclay at kinematics corresponding to mean neutron recoil momenta near 30 and 75 MeV. Differential cross sections were obtained for photon energies between E γ = 200 and 450 MeV at proton emission angles relative to the p − p center of mass of 49° and 75°, and a proton angular distribution was obtained at E γ = 350 MeV. The cross section for photon absorption by a p − p pair is found to be lower by two orders of magnitude compared to that for a p − n pair in 3 He. Theoretical multiple scattering calculations reproduce the data rather well, except for significant discrepancies at low E γ and forward proton angles.
Published: 1993

26. Measurement of theRLT,RL, andRTresponse functions for theHe4(e,e’p)3H reaction at large missing momentum

Author: J. Morrison, William Bertozzi, B. Jiang, J. R. Calarco, P. E. Ulmer, D. J. Margaziotis, K. A. Aniol, M. B. Epstein, H. Baghaei, C. C. Chang, Larry Weinstein, V. A. Punjabi, S. Penn, C. F. Perdrisat, P. Boberg, R.W. Lourie, J. M. Finn, J. M. Laget, and W. Boeglin
Subjects: Nuclear reaction, Physics, Statistics::Theory, Particle physics, Statistics::Applications, Meson, Hadron, Plane wave, General Physics and Astronomy, Elementary particle, Baryon, Helium-3, Nucleon, Mathematical physics
Abstract: The $^{4}\mathrm{He}$(e,e'p${)}^{3}$H reaction has been measured at a missing momentum of 265 MeV/c. Data were taken to determine the ${\mathit{R}}_{\mathit{L}}$, ${\mathit{R}}_{\mathit{T}}$, and ${\mathit{R}}_{\mathit{L}\mathit{T}}$ response functions. The extracted response functions show substantial differences from a microscopic calculation that includes the plane wave impulse approximation, final state interactions, and meson exchange currents, but agree much better with a calculation that includes orthogonality corrections, short range correlations, and final state interactions.
Published: 1993

27. Tensor Correlations Measured inHe3(e,e′pp)n

Author: D. Keller, M. Khandaker, B. McKinnon, G. Rosner, R. W. Gothe, V. Kuznetsov, A. Deur, N. Markov, W. K. Brooks, H. Hakobyan, J. M. Laget, M. Battaglieri, D. J. Tedeschi, I. Bedlinskiy, A. Kim, W. Kim, D. Doughty, P. Nadel-Turonski, R. P. Bennett, D. Protopopescu, Friedrich Klein, R. A. Schumacher, V. P. Kubarovsky, S. Pozdniakov, E. Voutier, E. Munevar, G. Niculescu, O. Pogorelko, S. E. Kuhn, R. Paremuzyan, C. E. Hyde, K. Joo, M. Ripani, Y. Ilieva, A. I. Ostrovidov, P. Khetarpal, S. Strauch, K. Park, Gerard Gilfoyle, G. Ricco, H. Avakian, W. Gohn, D. G. Ireland, B. Zhao, A. El Alaoui, C. S. Nepali, D. Sokhan, S. Bültmann, Volker D. Burkert, A. S. Biselli, M. Anghinolfi, N. D. Kvaltine, H. Seraydaryan, P. Konczykowski, C. Djalali, I. J. D. MacGregor, S. Stepanyan, S. Procureur, J. W. Price, R. Dupre, S. Park, B. L. Berman, J. P. Ball, K. L. Giovanetti, D. S. Carman, R. De Vita, P. Rossi, Martin K. Mayer, Avraham Klein, B. Moreno, Larry Weinstein, W. J. Briscoe, E. Pasyuk, K. A. Griffioen, H. Moutarde, K. Livingston, V. Crede, S. Anefalos Pereira, S. Niccolai, R. Dickson, C. Salgado, G. E. Dodge, H. Y. Lu, E. De Sanctis, B. Morrison, W. Tang, M. Amarian, M. Aghasyan, I. Niculescu, D. I. Sober, S. Fegan, M. Osipenko, J. McAndrew, F. Sabatié, Michael Vineyard, C. Bookwalter, Michael Wood, N. Dashyan, H. Baghdasaryan, C. Hanretty, Victor Mokeev, M. Ungaro, S. Pisano, V. Gyurjyan, P. Eugenio, M. Taiuti, Z. W. Zhao, Sergey Kuleshov, S. S. Stepanyan, M. Guidal, M. Holtrop, A. Daniel, George Davey Smith, C. E. Taylor, A. D'Angelo, L. El Fassi, L. Guo, P. Stoler, B. Dey, K. Hicks, K. Mikhailov, D. P. Watts, H. Egiyan, M. Y. Gabrielyan, Kei Moriya, C. A. Meyer, K. P. Adhikari, and D. P. Weygand
Subjects: Physics, Nuclear reaction, Particle physics, 010308 nuclear & particles physics, Hadron, General Physics and Astronomy, Elementary particle, Few-body systems, 01 natural sciences, Baryon, Nuclear physics, Momentum, Pair production, 0103 physical sciences, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: We have measured the $^{3}\mathrm{He}(e,{e}^{\ensuremath{'}}pp)n$ reaction at an incident energy of 4.7 GeV over a wide kinematic range. We identified spectator correlated $pp$ and $pn$ nucleon pairs by using kinematic cuts and measured their relative and total momentum distributions. This is the first measurement of the ratio of $pp$ to $pn$ pairs as a function of pair total momentum ${p}_{\mathrm{tot}}$. For pair relative momenta between 0.3 and $0.5\text{ }\text{ }\mathrm{GeV}/c$, the ratio is very small at low ${p}_{\mathrm{tot}}$ and rises to approximately 0.5 at large ${p}_{\mathrm{tot}}$. This shows the dominance of tensor over central correlations at this relative momentum.
Published: 2010

28. Full phase space measurement of the reaction analysing power using a free polarized neutron beam from 572 to 1134 MeV

Author: B. Fabbro, J.-M. Laget, G. Bruge, R. Beurtey, J.C. Faivre, M. Rouger, P. Couvert, Y. Terrien, F. Wellers, J. Saudinos, and C. Kerboul
Subjects: Physics, Nuclear physics, Nuclear and High Energy Physics, Amplitude, Phase space, Detector, Solid angle, Intermediate state, Kinematics, Atomic physics, Neutron radiation, Event (particle physics)
Abstract: Experimental results on the study of the n p → pp π − reaction performed with a 4π solid angle detector are presented. Full kinematics is measured event by event. Measured analysing powers are compared to the results of a calculation including the ΔN intermediate state and realistic non-resonant amplitudes.
Published: 1992

29. The reactions and the components of the 3He wave function

Author: J. M. Laget
Subjects: Nuclear physics, Momentum, Physics, Nuclear and High Energy Physics, Particle physics, Meson, Scattering, Momentum transfer, Virtual particle, Electron, Wave function, Spin-½
Abstract: Spin observables in exclusive and semi-inclusive quasi-elastic scattering of polarized electrons on a polarized 3 He target provides us with a powerful way to disentangle the dominant components of its wave function. However, the contributions of Final State Interactions and Meson Exchange Currents are sizeable for large values of the missing momentum, in the kinematical domain covered by the present generation of electron accelerators (virtual photon momentum pf the order of 500 MeV/ c . They become small when the momentum of the virtual photon is larger than 1 GeV/ c .
Published: 1992

30. Photodisintegration ofHe4intop+t

Author: A. I. Ostrovidov, K. Park, G. E. Dodge, H. Y. Lu, Volker D. Burkert, K. Livingston, A. S. Biselli, R. Dickson, L. Guo, G. Rosner, R. Fersch, M. Ungaro, I. Niculescu, A. Fradi, M. Osipenko, R. Dupre, S. Pisano, M. Battaglieri, E. De Sanctis, C. E. Hyde, R. Nasseripour, Marco Ripani, C. Djalali, D. I. Sober, B. McKinnon, K. A. Griffioen, B. Zhao, D. P. Watts, E. Wolin, V. Kuznetsov, D. Branford, A. Deur, J. M. Laget, W. J. Briscoe, E. Pasyuk, P. L. Cole, P. Ambrozewicz, Paolo Rossi, S. S. Jawalkar, Y. Ilieva, J. P. Ball, Y. Prok, D. S. Carman, W. K. Brooks, S. Procureur, S. Niccolai, M. Y. Gabrielyan, P. Stoler, Friedrich Klein, Z. W. Zhao, R. De Vita, R. A. Schumacher, S. Dhamija, M. J. Amaryan, A. D'Angelo, Brian Raue, B. Dey, Gerard Gilfoyle, K. Hicks, P. Nadel-Turonski, R. W. Gothe, V. P. Kubarovsky, S. Strauch, H. Hakobyan, S. Park, D. Sokhan, B. L. Berman, M. Taiuti, S. Anefalos Pereira, M. E. McCracken, O. Pogorelko, W. Kim, D. J. Tedeschi, R. Suleiman, G. Niculescu, W. Gohn, F. X. Girod, N. Hassall, D. Protopopescu, I. Bedlinskiy, Michael Wood, S. L. Careccia, P. Khetarpal, S. Pozdniakov, P. Collins, S. Fegan, C. S. Nepali, P. Corvisiero, S. Stepanyan, Giovanni Ricco, E. Golovatch, J. W. Price, D. G. Ireland, E. Munevar, C. Bookwalter, Avraham Klein, N. Dashyan, F. Sabatié, M. R. Niroula, H. Baghdasaryan, K. L. Giovanetti, K. Joo, J. Salamanca, Larry Weinstein, B. Morrison, D. Doughty, T. Mineeva, D. Heddle, C. Salgado, S. Tkachenko, N. Benmouna, D. Keller, E. L. Isupov, Michael L. Williams, M. Khandaker, S. E. Kuhn, Michael Vineyard, M. Anghinolfi, H. Seraydaryan, Y. G. Sharabian, Martin K. Mayer, M. S. Saini, J. T. Goetz, M. Mirazita, S. S. Stepanyan, Sergey Kuleshov, M. Guidal, A. Daniel, Barry Ritchie, Kei Moriya, G. V. Fedotov, K. P. Adhikari, D. P. Weygand, J. Zhang, C. Hanretty, Victor Mokeev, and J. R. Johnstone
Subjects: Nuclear physics, Nuclear reaction, Physics, Nuclear and High Energy Physics, Proton, Photodisintegration, Helium-3, Hadron, Bremsstrahlung, Nucleon, Isotopes of helium
Abstract: The two-body photodisintegration of {sup 4}He into a proton and a triton has been studied using the CEBAF Large-Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. Real photons produced with the Hall-B bremsstrahlung-tagging system in the energy range from 0.35 to 1.55 GeV were incident on a liquid {sup 4}He target. This is the first measurement of the photodisintegration of {sup 4}He above 0.4 GeV. The differential cross sections for the {gamma}{sup 4}He{yields}pt reaction were measured as a function of photon-beam energy and proton-scattering angle and are compared with the latest model calculations by J.-M. Laget. At 0.6-1.2 GeV, our data are in good agreement only with the calculations that include three-body mechanisms, thus confirming their importance. These results reinforce the conclusion of our previous study of the three-body breakup of {sup 3}He that demonstrated the great importance of three-body mechanisms in the energy region 0.5-0.8 GeV.
Published: 2009

31. Measurement of the Differential Cross Section for the Reactionγn→π−pfrom Deuterium

Author: S. Park, M. J. Amaryan, D. P. Watts, H. Egiyan, S. L. Careccia, M. Ungaro, P. Rossi, K. L. Giovanetti, Larry Weinstein, C. Djalali, Michael Wood, B. S. Ishkhanov, D. Keller, A. Yegneswaran, M. Battaglieri, P. Eugenio, M. R. Niroula, M. Khandaker, S. Tkachenko, M. E. McCracken, W. Gohn, Tsutomu Mibe, M. Taiuti, M. Ripani, K. Hicks, S. E. Kuhn, W. J. Briscoe, S. Strauch, W. Kim, W. Chen, J. Salamanca, D. Doughty, D. Heddle, G. Ricco, T. Mineeva, Dipangkar Dutta, J. Zhang, P. Khetarpal, P. Collins, Y. Ilieva, D. Protopopescu, P. Nadel-Turonski, V. Crede, L. Casey, N. Hassall, M. Bellis, R. Nasseripour, S. Pozdniakov, M. Garçon, I. I. Strakovsky, C. Hanretty, A. Deur, Friedrich Klein, M. Osipenko, V. P. Kubarovsky, F. Sabatié, W. K. Brooks, O. Pogorelko, K. A. Griffioen, Brian Raue, J. R. Johnstone, R. De Vita, V. Kuznetsov, S. Procureur, Barry Ritchie, P. L. Cole, M. Anghinolfi, V. Mokeev, B. L. Berman, Kei Moriya, S. Anefalos Pereira, C. A. Meyer, G. V. Fedotov, C. E. Hyde, Y. G. Sharabian, D. P. Weygand, E. De Sanctis, D. I. Sober, M. S. Saini, S. Niccolai, H. Hakobyan, D. J. Tedeschi, B. Moreno, K. Livingston, R. Dickson, R. A. Schumacher, G. Rosner, S. Stepanyan, Avraham Klein, G. E. Dodge, H. Y. Lu, I. Niculescu, K. Joo, A. I. Ostrovidov, K. Park, D. G. Ireland, Volker D. Burkert, B. Zhao, A. S. Biselli, Laird Kramer, Sergey Kuleshov, D. S. Carman, F. X. Girod, Haiyan Gao, J. W. Price, N. Dashyan, A. Fradi, N. Markov, S. S. Stepanyan, S. Dhamija, R. W. Gothe, H. Bagdasaryan, Gerard Gilfoyle, Michael Vineyard, M. Guidal, D. Sokhan, M. Holtrop, A. Daniel, B. McKinnon, D. Branford, C. Bookwalter, M. Mirazita, J. M. Laget, H. S. Jo, C. Salgado, and E. L. Isupov
Subjects: Massless particle, Physics, Particle physics, Pion, Meson, Photodisintegration, Hadron, General Physics and Astronomy, High Energy Physics::Experiment, Elementary particle, Nuclear Experiment, Energy (signal processing), Boson
Abstract: We report a measurement of the differential cross section for the $$\gamma n \to \pi^- p$$ process from the CLAS detector at Jefferson Lab in Hall B for photon energies between 1.0 and 3.5 GeV and pion center-of-mass (c.m.) angles ($$\theta_{c.m.}$$) between 50$$^\circ$$ and 115$$^\circ$$. We confirm a previous indication of a broad enhancement around a c.m. energy ($$\sqrt{s}$$) of 2.2 GeV at $$\theta_{c.m.}=90^\circ$$ in the scaled differential cross section, $$s^7 {\frac{d\sigma}{dt}}$$. Our data show the angular dependence of this enhancement as the scaling region is approached in the kinematic region from 70$$^\circ$$ to 105$$^\circ$$.
Published: 2009

32. Precise Measurement of the Neutron Magnetic Form FactorGMnin the Few-GeV2Region

Author: R. J. Feuerbach, J. P. Cummings, L. C. Smith, E. Munevar, R. De Masi, D. Keller, M. Kossov, B. S. Ishkhanov, I. Popa, K. S. Egiyan, G. Ricco, K. Mikhailov, L. Cheng, M. Khandaker, M. Garçon, J. Shaw, Michael Wood, P. Nadel-Turonski, Nikolay Shvedunov, M. R. Niroula, K. Hafidi, R. Nasseripour, S. McAleer, Friedrich Klein, B. P. Quinn, Brian Raue, V. S. Serov, L. Casey, F. X. Girod, Susan Taylor, Marco A. Huertas, M. Lowry, V. Sapunenko, D. P. Watts, L. C. Dennis, B. E. Bonner, Hartmuth Arenhövel, Dinko Pocanic, H. Egiyan, R. G. Fersch, H. Avakian, D. Doughty, B. B. Niczyporuk, G. S. Adams, S. Park, D. Sharov, N. Kalantarians, P. L. Cole, Sylvain Bouchigny, Sabine Jeschonnek, R. C. Minehart, Kei Moriya, D. Heddle, P. Rossi, J. Lachniet, H. G. Juengst, C. A. Meyer, N. Pivnyuk, K. Joo, W. J. Briscoe, B. L. Berman, A. Tkabladze, G. V. Fedotov, E. Pasyuk, D. Rowntree, A. Coleman, L. M. Qin, M. Y. Gabrielyan, S. E. Kuhn, S. A. Dytman, V. Crede, Y. Ilieva, J. R. Calarco, T. Mineeva, J. W. Price, M. J. Amaryan, C. Paterson, S. Strauch, M. MacCormick, A.V. Stavinsky, M. Klusman, I. Hleiqawi, V. P. Kubarovsky, K. P. Adhikari, S. L. Careccia, A. Empl, L. El Fassi, O. Pogorelko, B. Moreno, D. P. Weygand, J. Salamanca, R. Suleiman, M. E. McCracken, Elton Smith, K. L. Giovanetti, B. Asavapibhop, G. V. O'Rielly, Tsutomu Mibe, Larry Weinstein, Z. W. Zhao, J. W C McNabb, D. J. Tedeschi, D. Protopopescu, D. G. Jenkins, Barry Ritchie, M. Anghinolfi, James Mueller, S. Malace, S. A. Morrow, P. Rubin, I. Bedlinskiy, G. S. Mutchler, Konstantin Stopani, S. Pozdniakov, V. Gyurjyan, M. M. Ito, C. Djalali, Y. G. Sharabian, G. Rosner, T. Kageya, K. Livingston, D. S. Dale, X. Wei, R. Dickson, V. Kuznetsov, C. E. Hyde-Wright, H. Denizli, N. Guler, N. A. Baltzell, P. Mattione, K. A. Griffioen, M. S. Saini, A. V. Skabelin, P. Dragovitsch, J. Zhang, S. Barrow, E. De Sanctis, S. Niccolai, J. T. Goetz, E. Polli, H. Bagdasaryan, R. A. Miskimen, J. D. Kellie, B. McKinnon, Sergey Kuleshov, M. Bektasoglu, J. Hardie, M. Nozar, W. Kim, Laird Kramer, G. Niculescu, D. I. Sober, D. Branford, M. Guidal, R. A. Schumacher, H. Hakobyan, M. Mirazita, P. Khetarpal, C. Hanretty, J. M. Laget, M. Holtrop, Victor Mokeev, L. Graham, J. R. Johnstone, N. Gevorgyan, L. Guo, M. Ungaro, M. Osipenko, F. Sabatié, A. Daniel, K. Beard, Kalvir S. Dhuga, S. Bültmann, A. I. Ostrovidov, J. Yun, D. Cords, V. Batourine, T. A. Forest, A. Yegneswaran, A. C S Lima, A. Sandorfi, K. Park, R. Fatemi, S. Stepanyan, A. V. Vlassov, D. G. Ireland, Volker D. Burkert, A. S. Biselli, J. Pierce, Avraham Klein, B. Zhao, J. Langheinrich, R. De Vita, A. Fradi, S. S. Stepanyan, S. A. Philips, William Brooks, N. Markov, P. Konczykowski, B. E. Stokes, J. J. Manak, S. Anefalos Pereira, G. E. Dodge, H. Y. Lu, N. Dashyan, Maryam Moteabbed, P. V. Degtyarenko, K. V. Dharmawardane, I. Niculescu, D. Lawrence, D. Schott, F. W. Hersman, M. Battaglieri, N. Baillie, P. Stoler, K. Hicks, G. Asryan, O. P. Dzyubak, R. A. Niyazov, P. Corvisiero, R. Bradford, B. A. Mecking, K. Lukashin, E. Wolin, Gerard Gilfoyle, M. Guillo, D. Sokhan, W. Gohn, N. Hassall, M. Bellis, E. Golovatch, J. P. Ball, J. Hu, Y. Prok, D. S. Carman, S. Dhamija, M. D. Mestayer, L. Elouadrhiri, I. I. Strakovsky, E. L. Isupov, R. W. Gothe, G. Gavalian, S. Tkachenko, A. Deur, Michael L. Williams, J. Kuhn, N. Benmouna, J. P. Santoro, Andrei Afanasev, M. Ripani, D. G. Crabb, K. Y. Kim, Roy Thompson, Cynthia Marie Hadjidakis, S. Boiarinov, Michael Dugger, B. M. Preedom, Douglas Higinbotham, M. Yurov, Lorenzo Zana, H. S. Jo, C. Bookwalter, C. Salgado, Kwangsoo Kim, G. Riccardi, P. Eugenio, A. Starostin, M. Taiuti, Michael Vineyard, and P. Collins
Subjects: Physics, 010308 nuclear & particles physics, Scattering, Nuclear Theory, General Physics and Astronomy, Scintillator, 7. Clean energy, 01 natural sciences, Nuclear physics, Dipole, Deuterium, 0103 physical sciences, Magnetic form factor, Neutron detection, High Energy Physics::Experiment, Neutron, Nuclear Experiment, 010306 general physics, Electron scattering
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: 2009

33. Search for the Photoexcitation of Exotic Mesons in theπ+π+π−System

Author: M. Nozar, C. Salgado, D. P. Weygand, L. Guo, G. Adams, Ji Li, P. Eugenio, M. J. Amaryan, M. Anghinolfi, G. Asryan, H. Avakian, H. Bagdasaryan, N. Baillie, J. P. Ball, N. A. Baltzell, S. Barrow, M. Battaglieri, I. Bedlinskiy, M. Bektasoglu, M. Bellis, N. Benmouna, B. L. Berman, A. S. Biselli, L. Blaszczyk, B. E. Bonner, S. Bouchigny, S. Boiarinov, R. Bradford, D. Branford, W. J. Briscoe, W. K. Brooks, S. Bültmann, V. D. Burkert, C. Butuceanu, J. R. Calarco, S. L. Careccia, D. S. Carman, B. Carnahan, L. Casey, A. Cazes, S. Chen, L. Cheng, P. L. Cole, P. Collins, P. Coltharp, D. Cords, P. Corvisiero, D. Crabb, H. Crannell, V. Crede, J. P. Cummings, D. Dale, N. Dashyan, R. De Masi, R. De Vita, E. De Sanctis, P. V. Degtyarenko, H. Denizli, L. Dennis, A. Deur, K. V. Dharmawardane, K. S. Dhuga, R. Dickson, C. Djalali, G. E. Dodge, D. Doughty, M. Dugger, S. Dytman, O. P. Dzyubak, H. Egiyan, K. S. Egiyan, L. El Fassi, L. Elouadrhiri, R. Fatemi, G. Fedotov, R. J. Feuerbach, T. A. Forest, A. Fradi, H. Funsten, M. Garçon, G. Gavalian, N. Gevorgyan, G. P. Gilfoyle, K. L. Giovanetti, F. X. Girod, J. T. Goetz, R. W. Gothe, K. A. Griffioen, M. Guidal, M. Guillo, N. Guler, V. Gyurjyan, C. Hadjidakis, K. Hafidi, H. Hakobyan, C. Hanretty, J. Hardie, N. Hassall, D. Heddle, F. W. Hersman, K. Hicks, I. Hleiqawi, M. Holtrop, C. E. Hyde-Wright, Y. Ilieva, D. G. Ireland, B. S. Ishkhanov, E. L. Isupov, M. M. Ito, D. Jenkins, H. S. Jo, J. R. Johnstone, K. Joo, H. G. Juengst, N. Kalantarians, J. D. Kellie, M. Khandaker, W. Kim, A. Klein, F. J. Klein, M. Kossov, Z. Krahn, L. H. Kramer, V. Kubarovsky, J. Kuhn, S. E. Kuhn, S. V. Kuleshov, V. Kuznetsov, J. Lachniet, J. M. Laget, J. Langheinrich, D. Lawrence, K. Livingston, H. Y. Lu, M. MacCormick, N. Markov, P. Mattione, S. McAleer, B. McKinnon, J. W. C. McNabb, B. A. Mecking, S. Mehrabyan, M. D. Mestayer, C. A. Meyer, T. Mibe, K. Mikhailov, M. Mirazita, R. Miskimen, V. Mokeev, B. Moreno, K. Moriya, S. A. Morrow, M. Moteabbed, J. Mueller, E. Munevar, G. S. Mutchler, P. Nadel-Turonski, R. Nasseripour, S. Niccolai, G. Niculescu, I. Niculescu, B. B. Niczyporuk, M. R. Niroula, R. A. Niyazov, G. V. O’Rielly, M. Osipenko, A. I. Ostrovidov, K. Park, E. Pasyuk, C. Paterson, S. Anefalos Pereira, S. A. Philips, J. Pierce, N. Pivnyuk, D. Pocanic, O. Pogorelko, E. Polli, I. Popa, S. Pozdniakov, B. M. Preedom, J. W. Price, Y. Prok, D. Protopopescu, L. M. Qin, B. A. Raue, G. Riccardi, G. Ricco, M. Ripani, B. G. Ritchie, F. Ronchetti, G. Rosner, P. Rossi, P. D. Rubin, F. Sabatié, J. Salamanca, J. P. Santoro, V. Sapunenko, R. A. Schumacher, V. S. Serov, Y. G. Sharabian, D. Sharov, N. V. Shvedunov, A. V. Skabelin, E. S. Smith, L. C. Smith, D. I. Sober, D. Sokhan, A. Stavinsky, S. S. Stepanyan, S. Stepanyan, B. E. Stokes, P. Stoler, I. I. Strakovsky, S. Strauch, M. Taiuti, D. J. Tedeschi, U. Thoma, A. Tkabladze, S. Tkachenko, L. Todor, M. Ungaro, M. F. Vineyard, A. V. Vlassov, D. P. Watts, L. B. Weinstein, M. Williams, E. Wolin, M. H. Wood, A. Yegneswaran, L. Zana, J. Zhang, B. Zhao, and Z. W. Zhao
Subjects: Quantum chromodynamics, Physics, Particle physics, Meson, 010308 nuclear & particles physics, Partial wave analysis, Bremsstrahlung, General Physics and Astronomy, 01 natural sciences, 7. Clean energy, Nuclear physics, Excited state, 0103 physical sciences, Isobar, Production (computer science), 010306 general physics, Spin-½
Abstract: A search for exotic mesons in the $$\pi^{+}\pi^{+}\pi^{-}$$ system photoproduced by the charge exchange reaction $$\gamma p\to \pi^{+}\pi^{+}\pi^{-}(n)$$ was carried out by the CLAS collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target. A Partial Wave Analysis (PWA) was performed on a sample of 83,000 events, the highest such statistics to date in this reaction at these energies. The main objective of this study was to look for the photoproduction of an exotic $$J^{PC} = 1^{-+}$$ resonant state in the 1 to 2 GeV mass range. Our PWA analysis, based on the isobar model, shows production of the $$a_{2}(1320)$$ and the $$\pi_{2}(1670)$$ mesons, but no evidence for the $$a_{1}(1260)$$, nor the $$\pi_{1}(1600)$$ exotic state at the expected levels. An upper limit of 13.5 nb is determined for the exotic $$\pi_1(1600)$$ cross section, less than 2% of the $a_2(1320)
Published: 2009

34. Measurement of Directf0(980)Photoproduction on the Proton

Author: S. Park, Sylvain Bouchigny, V. Crede, J. R. Calarco, E. Wolin, C. E. Hyde, R. A. Schumacher, V. Sapunenko, Dinko Pocanic, P. Nadel-Turonski, L. Casey, V. Mokeev, D. Lawrence, J. P. Cummings, H. G. Juengst, B. E. Stokes, Cynthia Marie Hadjidakis, J. P. Ball, D. S. Carman, A. Fradi, A. V. Vlassov, P. Konczykowski, M. J. Amaryan, S. Dhamija, Michael Dugger, K. Livingston, D. S. Dale, T. Lee, Maryam Moteabbed, M. Kossov, S. E. Kuhn, L. Graham, Ashot Gasparian, B. B. Niczyporuk, C. I O Gordon, M. MacCormick, R. W. Gothe, Z. W. Zhao, R. Dickson, N. Gevorgyan, T. Kageya, H. Avakian, I. Hleiqawi, K. V. Dharmawardane, A.V. Stavinsky, J. Donnelly, G. Asryan, N. Pivnyuk, D. G. Crabb, J. Kuhn, M. E. McCracken, R. De Vita, S. Strauch, E. Clinton, S. Bültmann, S. L. Careccia, D. G. Jenkins, O. P. Dzyubak, D. P. Watts, H. Egiyan, Gerard Gilfoyle, G. Ricco, Lorenzo Zana, J. P. Santoro, C. Tur, L. Gan, Tsutomu Mibe, W. Gohn, T. A. Forest, D. J. Tedeschi, N. Markov, D. Sokhan, D. Sharov, W. Kim, S. Anefalos Pereira, S. Stepanyan, G. Niculescu, M. Yurov, J. Goett, R. A. Miskimen, I. Bedlinskiy, B. McKinnon, M. Y. Gabrielyan, J. Pierce, K. L. Giovanetti, F. X. Girod, Sergey Kuleshov, Avraham Klein, Shifeng Chen, N. Guler, E. Golovatch, Friedrich Klein, Larry Weinstein, N. A. Baltzell, G. E. Dodge, P. Khetarpal, K. A. Stopani, Brian Raue, D. Keller, H. Y. Lu, M. Nozar, D. Branford, J. Salamanca, H. S. Jo, C. Bookwalter, E. De Sanctis, L. Lesniak, G. Riccardi, J. M. Laget, V. V. Mochalov, P. Mattione, K. A. Griffioen, M. Aghasyan, X. Wei, V. Kuznetsov, M. S. Saini, P. V. Degtyarenko, A. I. Ostrovidov, D. I. Sober, A. Sandorfi, K. Park, P. Eugenio, Adam P. Szczepaniak, V. Batourine, C. Hanretty, A. Starostin, M. Guidal, N. Dashyan, M. Taiuti, W. J. Briscoe, E. Pasyuk, H. Hakobyan, S. A. Morrow, G. Rosner, J. T. Goetz, M. Mirazita, C. Djalali, Paolo Rossi, M. Khandaker, L. Bibrzycki, I. Niculescu, J. Lachniet, A. Tkabladze, Y. Ilieva, J. W. Price, M. Holtrop, R. A. Niyazov, Elton Smith, D. G. Ireland, A. Daniel, A. Teymurazyan, I. I. Strakovsky, G. Gavalian, N. Hassall, M. Bellis, P. Ambrozewicz, P. Collins, B. Zhao, R. De Masi, S. Tkachenko, D. Schott, M. Ripani, D. Doughty, P. Stoler, J. J. Melone, S. Niccolai, Z. Krahn, Volker D. Burkert, A. S. Biselli, M. Anghinolfi, C. Salgado, N. Benmouna, J. Langheinrich, S. S. Stepanyan, D. Heddle, J. D. Kellie, A. Deur, N. Baillie, T. Mineeva, S. Malace, Mark W. Paris, J. R. Johnstone, Hall Crannell, M. Osipenko, V. P. Kubarovsky, Y. G. Sharabian, Laird Kramer, L. Cheng, W. K. Brooks, J. Hardie, F. W. Hersman, R. S. Hakobyan, L. Guo, M. Ungaro, B. Moreno, O. Pogorelko, G. S. Mutchler, K. Hicks, Nikolay Shvedunov, D. Protopopescu, B. L. Berman, K. S. Egiyan, L. El Fassi, S. Pozdniakov, M. Garçon, Michael Wood, K. Mikhailov, K. Hafidi, V. S. Serov, M. Battaglieri, N. Kalantarians, R. Bradford, B. A. Mecking, R. Nasseripour, K. Joo, A. Yegneswaran, Michael Vineyard, V. Gyurjyan, J. Zhang, H. Bagdasaryan, L. Todor, R. G. Fersch, C. Paterson, Ji Li, P. L. Cole, M. D. Mestayer, E. L. Isupov, Michael L. Williams, M. M. Ito, S. Boiarinov, F. Sabatié, L. C. Smith, E. Munevar, B. S. Ishkhanov, M. R. Niroula, M. Lowry, Latifa Elouadrhiri, R. C. Minehart, Kei Moriya, C. A. Meyer, G. V. Fedotov, K. P. Adhikari, D. P. Weygand, O. Glamazdin, Alexei V. Klimenko, Y. Prok, Barry Ritchie, and I. Nakagawa
Subjects: Physics, Particle physics, Proton, Meson, 010308 nuclear & particles physics, Partial wave analysis, Hadron, General Physics and Astronomy, Resonance, 01 natural sciences, 7. Clean energy, Nuclear physics, Particle decay, Pion, 0103 physical sciences, 010306 general physics, Nucleon
Abstract: We report on the results of the first measurement of exclusive f{sub 0}(980) meson photoproduction on protons for E{sub {gamma}}=3.0-3.8 GeV and -t=0.4-1.0 GeV{sup 2}. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. The resonance was detected via its decay in the {pi}{sup +}{pi}{sup -} channel by performing a partial wave analysis of the reaction {gamma}p{yields}p{pi}{sup +}{pi}{sup -}. Clear evidence of the f{sub 0}(980) meson was found in the interference between P and S waves at M{sub {pi}{sup +}}{sub {pi}{sup -}}{approx}1 GeV. The S-wave differential cross section integrated in the mass range of the f{sub 0}(980) was found to be a factor of about 50 smaller than the cross section for the {rho} meson. This is the first time the f{sub 0}(980) meson has been measured in a photoproduction experiment.
Published: 2009

35. Measurement of the differential cross section for the reaction gamman--pi- p from deuterium

Author: W, Chen, T, Mibe, D, Dutta, H, Gao, J M, Laget, M, Mirazita, P, Rossi, S, Stepanyan, I I, Strakovsky, M J, Amaryan, M, Anghinolfi, H, Bagdasaryan, M, Battaglieri, M, Bellis, B L, Berman, A S, Biselli, C, Bookwalter, D, Branford, W J, Briscoe, W K, Brooks, V D, Burkert, S L, Careccia, D S, Carman, L, Casey, P L, Cole, P, Collins, V, Crede, A, Daniel, N, Dashyan, R, De Vita, E, De Sanctis, A, Deur, S, Dhamija, R, Dickson, C, Djalali, G E, Dodge, D, Doughty, H, Egiyan, P, Eugenio, G, Fedotov, A, Fradi, M, Garçon, G P, Gilfoyle, K L, Giovanetti, F X, Girod, W, Gohn, R W, Gothe, K A, Griffioen, M, Guidal, H, Hakobyan, C, Hanretty, N, Hassall, D, Heddle, K, Hicks, M, Holtrop, C E, Hyde, Y, Ilieva, D G, Ireland, B S, Ishkhanov, E L, Isupov, H S, Jo, J R, Johnstone, K, Joo, D, Keller, M, Khandaker, P, Khetarpal, W, Kim, A, Klein, F J, Klein, L H, Kramer, V, Kubarovsky, S E, Kuhn, S V, Kuleshov, V, Kuznetsov, K, Livingston, H Y, Lu, N, Markov, M E, McCracken, B, McKinnon, C A, Meyer, T, Mineeva, V, Mokeev, B, Moreno, K, Moriya, P, Nadel-Turonski, R, Nasseripour, S, Niccolai, I, Niculescu, M R, Niroula, M, Osipenko, A I, Ostrovidov, K, Park, S, Park, S Anefalos, Pereira, O, Pogorelko, S, Pozdniakov, J W, Price, S, Procureur, D, Protopopescu, B A, Raue, G, Ricco, M, Ripani, B G, Ritchie, G, Rosner, F, Sabatié, M S, Saini, J, Salamanca, C, Salgado, R A, Schumacher, Y G, Sharabian, D I, Sober, D, Sokhan, S S, Stepanyan, S, Strauch, M, Taiuti, D J, Tedeschi, S, Tkachenko, M, Ungaro, M F, Vineyard, D P, Watts, L B, Weinstein, D P, Weygand, M H, Wood, A, Yegneswaran, J, Zhang, and B, Zhao
Abstract: We report a measurement of the differential cross section for the gamman--pi- p process from the CLAS detector at Jefferson Laboratory in Hall B for photon energies between 1.0 and 3.5 GeV and pion center-of-mass (c.m.) angles (thetac.m.) between 50 degrees and 115 degrees. We confirm a previous indication of a broad enhancement around a c.m. energy ([sqrt]s) of 2.1 GeV at thetac.m.=90 degrees in the scaled differential cross section s7dsigma/dt and a rapid falloff in a center-of-mass energy region of about 400 MeV following the enhancement. Our data show an angular dependence of this enhancement as the suggested scaling region is approached for thetac.m. from 70 degrees to 105 degrees.
Published: 2009

36. Electroproduction ofpπ+π−off protons at0.2<Q2<0.6GeV2and1.3<W<1.57GeV with the CLAS detector

Author: P. Stoler, N. A. Baltzell, V. Crede, K. Hicks, J. R. Calarco, K. A. Griffioen, K. S. Egiyan, J. D. Kellie, C. Paterson, H. Denizli, S. Strauch, M. Klusman, M. Guidal, J. W C McNabb, K. Livingston, Nikolay Shvedunov, G. S. Mutchler, R. Dickson, Shifeng Chen, M. Osipenko, M. Holtrop, G. E. Dodge, V. Gyurjyan, P. Eugenio, P. V. Degtyarenko, Laird Kramer, J. Donnelly, G. Asryan, C. E. Hyde, O. P. Dzyubak, M. Taiuti, Marco A. Huertas, G. Rosner, T. Mineeva, J. Zhang, N. Guler, F. X. Girod, J. Langheinrich, I. Niculescu, V. Batourine, B. Carnahan, R. A. Niyazov, E. De Sanctis, Hovhannes Baghdasaryan, Sylvain Bouchigny, L. C. Smith, J. T. Goetz, J. P. Cummings, D. Lawrence, A.V. Stavinsky, B. B. Niczyporuk, P. Corvisiero, L. Guo, P. Rossi, B. S. Ishkhanov, M. Ungaro, R. A. Miskimen, B. McKinnon, H. G. Juengst, Susan Taylor, E. Wolin, D. I. Sober, J. W. Price, Konstantin Stopani, D. J. Tedeschi, V. Sapunenko, N. Pivnyuk, K. Mikhailov, Y. Prok, D. Branford, Dinko Pocanic, M. Mirazita, H. Egiyan, E. Golovatch, William Brooks, J. M. Laget, L. Todor, S. E. Kuhn, R. Fatemi, J. P. Ball, I. Bedlinskiy, Sergey Kuleshov, Rakhsha Nasseripour, Hall Crannell, M. Bektasoglu, A. Yegneswaran, B. E. Stokes, D. Protopopescu, S. Pozdniakov, A. V. Vlassov, K. V. Dharmawardane, D. S. Carman, G. S. Adams, C. Tur, T. Lee, G. Ricco, K. Joo, J. Kuhn, D. G. Jenkins, A. I. Ostrovidov, Roy Thompson, G. V. O'Rielly, K. Park, R. De Vita, R. A. Schumacher, Elton Smith, R. J. Feuerbach, Victor Mokeev, J. Shaw, Y. Ilieva, S. A. Morrow, C. Djalali, G. Niculescu, M. Anghinolfi, Michael Wood, D. G. Ireland, D. G. Crabb, M. D. Mestayer, P. Coltharp, Friedrich Klein, James Mueller, N. Dashyan, S. Bültmann, T. A. Forest, Brian Raue, G. Gavalian, N. Hassall, M. Bellis, M. Guillo, S. Stepanyan, S. Niccolai, M. M. Ito, E. L. Isupov, Volker D. Burkert, J. Pierce, Avraham Klein, A. S. Biselli, P. D. Rubin, J. Hardie, J. Hu, P. Ambrozewicz, M. Battaglieri, V. S. Serov, L. C. Dennis, Michael L. Williams, B. E. Bonner, R. Bradford, B. A. Mecking, S. Tkachenko, N. Benmouna, F. Sabatié, Y. G. Sharabian, H. Avakian, Kwangsoo Kim, C. Butuceanu, M. Ripani, N. Markov, S. Boiarinov, D. Sharov, Cynthia Marie Hadjidakis, Michael Dugger, H. O. Funsten, E. Pasyuk, S. A. Dytman, Latifa Elouadrhiri, R. C. Minehart, Kei Moriya, C. A. Meyer, A. Tkabladze, G. V. Fedotov, Michael Vineyard, D. P. Weygand, Alexei V. Klimenko, V. P. Kubarovsky, Barry Ritchie, O. Pogorelko, Lorenzo Zana, J. P. Santoro, H. S. Jo, D. Doughty, C. Salgado, M. E. McCracken, P. Nadel-Turonski, Tsutomu Mibe, M. Khandaker, N. Gevorgyan, Z. Krahn, J. Lachniet, N. Baillie, Gerard Gilfoyle, D. Rowntree, M. J. Amaryan, R. W. Gothe, I. Hleiqawi, K. Y. Kim, S. L. Careccia, P. L. Cole, K. L. Giovanetti, B. Asavapibhop, Larry Weinstein, F. W. Hersman, and W. Kim
Subjects: Baryon, Physics, Nuclear and High Energy Physics, Particle physics, Pion, Meson, Hadron, Elementary particle, Invariant mass, Sensitivity (control systems), Nucleon
Abstract: This paper reports on the most comprehensive data set obtained on differential and fully integrated cross sections for the process ep{yields}e{sup '}p{pi}{sup +}{pi}{sup -}. The data were collected with the CLAS detector at Jefferson Laboratory. Measurements were carried out in the as yet unexplored kinematic region of photon virtuality 0.2
Published: 2009

37. Photoproduction of pi+pi- meson pairs on the proton

Author: A. V. Vlassov, M. J. Amaryan, S. L. Careccia, E. Golovatch, W. Kim, R. De Vita, K. L. Giovanetti, D. Protopopescu, Martin K. Mayer, Larry Weinstein, D. P. Watts, H. Egiyan, S. Pozdniakov, M. Garçon, P. Khetarpal, Lorenzo Zana, G. E. Dodge, H. Y. Lu, Adam P. Szczepaniak, A. D'Angelo, I. Niculescu, C. S. Nepali, J. T. Goetz, K. Livingston, D. S. Dale, H. Hakobyan, L. Gan, M. Battaglieri, E. De Sanctis, Saini, Diane Schott, A. Deur, C. Hanretty, I. Nakagawa, A. I. Ostrovidov, B. Zhao, S. Fegan, D. I. Sober, K. Park, M. Y. Gabrielyan, L. Bibrzycki, A.V. Stavinsky, M. Khandaker, C. Bookwalter, D. G. Ireland, K. Moriya, P. Stoler, D. J. Tedeschi, Volker D. Burkert, A. S. Biselli, E. Wolin, Sergey Kuleshov, M. Osipenko, K. A. Griffioen, D. Doughty, Y. Prok, Gerard Gilfoyle, D. S. Carman, P. Eugenio, M. Taiuti, O. Glamazdin, K. Hicks, I. Bedlinskiy, A. Fradi, A. Gasparian, M. Kossov, Andreas Klein, D. Sokhan, N. Dashyan, J. Goett, B. McKinnon, Mokeev, M. Guidal, Barry Ritchie, Yordanka Ilieva, N. Hassall, M. Bellis, S. Park, K. Mikhailov, W. Gohn, S. Dhamija, D. Branford, S. Pisano, P. Collins, M. Mirazita, A. Teymurazyan, H. Baghdasaryan, R. W. Gothe, Leonard Lesniak, F. Sabatié, P. Rossi, J. M. Laget, Niroula, M. Holtrop, A. Daniel, E. L. Isupov, Crede, SA Pereira, Michael L. Williams, C. A. Meyer, G. V. Fedotov, S. Niccolai, S. Tkachenko, Mark W. Paris, M. Ripani, Carlos A. Salgado, Mochalov, M. Anghinolfi, K. P. Adhikari, Kuznetsov, D. P. Weygand, N. Pivnyuk, Michael Vineyard, C. Djalali, Drozdov, H. Seraydaryan, Y. G. Sharabian, P. L. Cole, Z. W. Zhao, M. E. McCracken, P. Nadel-Turonski, L. Guo, M. Ungaro, K. Joo, S. S. Stepanyan, C. E. Hyde, G. Rosner, J. Zhang, J. W. Price, R. A. Schumacher, G. Ricco, S. Stepanyan, W. J. Briscoe, E. Pasyuk, Brian Raue, Frank Klein, E. Munevar, Dustin Keller, A. Kubarovsky, Johnstone, Strakovsky, E. Clinton, Michael Wood, K. Hafidi, T. Mineeva, O. Pogorelko, Kubarovsky, F. X. Girod, S. Strauch, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), 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: PI-PI-DYNAMICS, COUPLED-CHANNEL, DIFFRACTION DISSOCIATION, POLARIZED PHOTONS, HIGH-STATISTICS, GEV-C, SYSTEM, MODEL, CLAS, CHAMBER, Nuclear and High Energy Physics, Particle physics, Meson, Proton, PI-PI-DYNAMICS, Photon energy, 01 natural sciences, 7. Clean energy, POLARIZED PHOTONS, High Energy Physics - Experiment, Settore FIS/04 - Fisica Nucleare e Subnucleare, Nuclear physics, Particle decay, Pion, CLAS, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], 010306 general physics, Nuclear Experiment, Physics, Luminosity (scattering theory), 010308 nuclear & particles physics, DIFFRACTION DISSOCIATION, Momentum transfer, COUPLED-CHANNEL, HIGH-STATISTICS, GEV-C, SYSTEM, MODEL, CHAMBER, Production (computer science), High Energy Physics::Experiment
Abstract: The exclusive reaction $$\gamma p \to p \pi^+ \pi^-$$ was studied in the photon energy range 3.0 - 3.8 GeV and momentum transfer range $0.4
Published: 2009

38. Measurement of semi-inclusive pi+ electroproduction off the proton

Author: L. C. Smith, E. Munevar, M. H. Wood, Y. Ilieva, M. E. McCracken, P. Nadel-Turonski, E. Wolin, R. J. Feuerbach, B. S. Ishkhanov, G. E. Dodge, Tsutomu Mibe, P. V. Degtyarenko, J. P. Ball, Y. Prok, D. S. Carman, M. R. Niroula, Alexander Ilyichev, O. P. Dzyubak, I. I. Strakovsky, Paolo Rossi, K. S. Egiyan, P. L. Cole, Z. W. Zhao, J. Lachniet, A. Tkabladze, W. Kim, I. Niculescu, R. A. Niyazov, D. G. Crabb, R. S. Hakobyan, L. El Fassi, Elton Smith, A. Deur, G. Niculescu, R. De Masi, B. L. Berman, J. Kuhn, B. McKinnon, W. K. Brooks, G. P. Gilfoyle, K. Livingston, R. Fatemi, N. Markov, A. V. Vlassov, J. P. Cummings, M. Anghinolfi, G. Ricco, B. Zhao, D. J. Tedeschi, S. Niccolai, R. Dickson, Ji Li, Y. G. Sharabian, S. Strauch, D. P. Watts, H. Egiyan, L. M. Qin, C. Paterson, L. Zana, D. Branford, J. M. Laget, M. Khandaker, G. Riccardi, N. Hassall, M. Bellis, Cynthia Marie Hadjidakis, R. De Vita, A. I. Ostrovidov, K. A. Griffioen, N. Guler, F. W. Hersman, J. Hardie, C. Butuceanu, M. J. Amaryan, M. Kossov, Shifeng Chen, E. N. Golovach, Volker D. Burkert, A. S. Biselli, Michael Dugger, J. Langheinrich, H. O. Funsten, H. G. Juengst, Luca Trentadue, M. MacCormick, I. Hleiqawi, M. D. Mestayer, C. Djalali, H. Denizli, P. Eugenio, S. Dytman, A. V. Skabelin, S. L. Careccia, I. Popa, P. Coltharp, R. A. Schumacher, P. Mattione, M. Osipenko, S. Barrow, M. Taiuti, A.V. Stavinsky, S. Anefalos Pereira, P. D. Rubin, R. W. Gothe, Laird Kramer, E. L. Isupov, D. Lawrence, D. Sokhan, M. M. Ito, H. Hakobyan, A. Cazes, J. R. Calarco, C. I O Gordon, K. L. Giovanetti, S. Mehrabyan, Alexei V. Klimenko, J. T. Goetz, R. Miskimen, C. Hanretty, G. V. O'Rielly, E. Polli, Michael L. Williams, Larry Weinstein, M. Mirazita, Kalvir S. Dhuga, J. D. Kellie, P. Collins, Friedrich Klein, F. Sabatié, Nikolay Shvedunov, J. J. Melone, V. Sapunenko, Sylvain Bouchigny, S. Bültmann, L. Todor, Barry Ritchie, Dinko Pocanic, Victor Mokeev, Brian Raue, G. Asryan, E. De Sanctis, M. Battaglieri, I. Bedlinskiy, V. A. Drozdov, S. Stepanyan, S. E. Kuhn, N. A. Baltzell, D. Protopopescu, S. Pozdniakov, M. Garçon, M. F. Vineyard, J. Pierce, Avraham Klein, Z. Krahn, N. Dashyan, S. Boiarinov, U. Thoma, D. I. Sober, R. Bradford, N. Kalantarians, Latifa Elouadrhiri, V. Gyurjyan, G. S. Mutchler, D. G. Ireland, V. Crede, N. Baillie, B. B. Niczyporuk, R. C. Minehart, Kei Moriya, S. McAleer, N. Pivnyuk, B. E. Stokes, J. Napolitano, G. S. Adams, J. Zhang, B. M. Preedom, F. X. Girod, L. Blaszczyk, H. Bagdasaryan, J. P. Santoro, C. Tur, C. A. Meyer, L. Guo, M. Ungaro, G. Gavalian, J. Donnelly, S. Tkachenko, D. Heddle, J. Salamanca, N. Benmouna, G. V. Fedotov, M. Ripani, J. W C McNabb, D. Jenkins, R. Nasseripour, S. A. Morrow, K. Joo, Maryam Moteabbed, Bernhard Mecking, K. V. Dharmawardane, A. Yegneswaran, Atilla Gonenc, P. Ambrozewicz, J. W. Price, M. Holtrop, D. P. Weygand, P. Corvisiero, H. S. Jo, Gerald Feldman, Federico A. Ceccopieri, C. Salgado, G. Rosner, M. Guillo, K. Mikhailov, M. Guidal, H. Y. Lu, C. E. Hyde-Wright, P. Stoler, Sergey Kuleshov, M. Bektasoglu, M. Nozar, K. Hicks, S. S. Stepanyan, S. A. Philips, J. Mueller, K. Hafidi, V. S. Serov, K. Park, V. P. Kubarovsky, O. Pogorelko, L. C. Dennis, B. E. Bonner, H. Avakian, W. J. Briscoe, E. Pasyuk, D. Doughty, 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 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: Particle physics, Nuclear and High Energy Physics, Proton, DEEP-INELASTIC-SCATTERING, TARGET FRAGMENTATION REGION, TRANSVERSE-MOMENTUM, PARTON DISTRIBUTIONS, AZIMUTHAL ASYMMETRY, PION ELECTROPRODUCTION, CHARGED HADRONS, HARD PROCESSES, LEADING ORDER, CROSS-SECTION, TARGET FRAGMENTATION REGION, Hadron, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Spectral line, Nuclear physics, Pion, Factorization, 0103 physical sciences, 010306 general physics, Nuclear Experiment, PION ELECTROPRODUCTION, Physics, DEEP-INELASTIC-SCATTERING, 010308 nuclear & particles physics, LEADING ORDER, TRANSVERSE-MOMENTUM, Azimuth, Diquark, CHARGED HADRONS, HARD PROCESSES, PARTON DISTRIBUTIONS, Cathode ray, AZIMUTHAL ASYMMETRY, High Energy Physics::Experiment, CROSS-SECTION
Abstract: Semi-inclusive {pi}{sup +} electroproduction on protons has been measured with the CLAS detector at Jefferson Lab. The measurement was performed on a liquid-hydrogen target using a 5.75 GeV electron beam. The complete five-fold differential cross sections were measured over a wide kinematic range including the complete range of azimuthal angles between hadronic and leptonic planes, {phi}, enabling us to separate the {phi}-dependent terms. Our measurements of the {phi}-independent term of the cross section at low Bjorken x were found to be in fairly good agreement with pQCD calculations. Indeed, the conventional current fragmentation calculation can account for almost all of the observed cross section, even at small {pi}{sup +} momentum. The measured center-of-momentum spectra are in qualitative agreement with high-energy data, which suggests a surprising numerical similarity between the spectator diquark fragmentation in the present reaction and the antiquark fragmentation measured in e{sup +}e{sup -} collisions. We have observed that the two {phi}-dependent terms of the cross section are small. Within our precision the cos2{phi} term is compatible with zero, except for the low-z region, and the measured cos{phi} term is much smaller in magnitude than the sum of the Cahn and Berger effects.
Published: 2009

39. Electroexcitation of the Roper resonance for1.7<Q2<4.5GeV2ine→p→enπ+

Author: B. Zhao, F. W. Hersman, Marco Ripani, S. Dhamija, R. W. Gothe, K. Y. Kim, J. Kuhn, J. P. Santoro, E. De Sanctis, Latifa Elouadrhiri, B. M. Preedom, P. Eugenio, R. C. Minehart, Kei Moriya, D. I. Sober, M. Taiuti, G. Rosner, C. A. Meyer, M. Battaglieri, G. V. Fedotov, P. Collins, J. J. Melone, Lorenzo Zana, R. Bradford, K. Lukashin, J. Shaw, V. Batourine, D. P. Weygand, H. Hakobyan, Friedrich Klein, H. S. Jo, Michael Wood, K. Hafidi, Brian Raue, Gerald Feldman, Elton Smith, R. Fatemi, V. S. Serov, A. V. Vlassov, T. Lee, M. Anghinolfi, P. Coltharp, James Mueller, I. I. Strakovsky, N. A. Baltzell, R. De Vita, P. D. Rubin, A. Cazes, Maryam Moteabbed, C. Salgado, Bernhard Mecking, Y. G. Sharabian, A. Deur, K. A. Griffioen, K. S. Egiyan, K. V. Dharmawardane, Baile Zhang, Alexei V. Klimenko, S. Anefalos Pereira, Z. Krahn, W. K. Brooks, Shifeng Chen, J. D. Kellie, Y. Prok, N. Hassall, M. Bellis, J. Langheinrich, Barry Ritchie, N. Baillie, P. Mattione, M. S. Saini, L. C. Dennis, B. E. Bonner, S. S. Stepanyan, S. A. Philips, R. A. Miskimen, B. McKinnon, H. Avakian, J. T. Goetz, E. Polli, B. L. Berman, D. Sharov, M. Mirazita, D. Branford, K. Livingston, D. S. Dale, Ji Li, L. M. Qin, J. M. Laget, H. Denizli, N. Gevorgyan, C. Paterson, G. Gavalian, W. J. Briscoe, E. Pasyuk, S. Tkachenko, M. D. Mestayer, S. A. Dytman, J. Donnelly, G. Asryan, A. V. Skabelin, N. Benmouna, Gerard Gilfoyle, O. P. Dzyubak, R. A. Niyazov, E. L. Isupov, A. Fradi, D. Sokhan, M. Guillo, V. Crede, Michael L. Williams, W. Gohn, N. Markov, V. Sapunenko, Dinko Pocanic, J. R. Calarco, P. Corvisiero, E. Golovatch, S. Boiarinov, S. E. Kuhn, Charles Hyde, V. P. Kubarovsky, O. Pogorelko, C. Tur, M. J. Amaryan, M. MacCormick, I. Hleiqawi, R. Nasseripour, S. L. Careccia, S. McAleer, F. X. Girod, Laird Kramer, B. E. Stokes, G. S. Adams, J. P. Cummings, Cynthia Marie Hadjidakis, G. E. Dodge, H. Y. Lu, K. L. Giovanetti, L. Blaszczyk, P. V. Degtyarenko, M. Kossov, V. Gyurjyan, K. Joo, I. Popa, Sergey Kuleshov, M. Bektasoglu, Michael Dugger, D. Heddle, M. Nozar, P. Stoler, I. Niculescu, D. Lawrence, J. Zhang, R. De Masi, D. Schott, S. A. Morrow, C. Djalali, R. A. Schumacher, M. Guidal, Larry Weinstein, K. Hicks, M. Holtrop, L. Graham, H. Bagdasaryan, C. I O Gordon, P. Ambrozewicz, S. Bültmann, L. Morand, T. A. Forest, S. Stepanyan, J. Pierce, Avraham Klein, K. Mikhailov, L. Cheng, Nikolay Shvedunov, A. I. Ostrovidov, L. Casey, A. C S Lima, K. Park, N. Kalantarians, B. B. Niczyporuk, D. G. Ireland, Michael Vineyard, N. Pivnyuk, Giovanni Ricco, Atilla Gonenc, E. Wolin, Volker D. Burkert, A. S. Biselli, J. P. Ball, D. S. Carman, D. G. Crabb, J. Salamanca, J. W C McNabb, M. Yurov, J. W. Price, S. Mehrabyan, C. Bookwalter, G. Riccardi, H. Funsten, P. Nadel-Turonski, C. Butuceanu, Tsutomu Mibe, N. Dashyan, K. Hafnaoui, C. Hanretty, G. V. O'Rielly, J. R. Johnstone, Z. W. Zhao, D. Keller, Paolo Rossi, D. G. Jenkins, J. Lachniet, A. Tkabladze, S. Park, Sylvain Bouchigny, D. Rowntree, M. M. Ito, R. S. Hakobyan, L. El Fassi, M. Khandaker, H. G. Juengst, A.V. Stavinsky, D. J. Tedeschi, V. Mokeev, I. Bedlinskiy, L. C. Smith, E. Munevar, B. S. Ishkhanov, M. R. Niroula, V. Kuznetsov, S. Strauch, R. Suleiman, L. Guo, G. S. Mutchler, M. Ungaro, S. Niccolai, J. Hardie, D. Doughty, W. Kim, D. P. Watts, G. Niculescu, J. Yun, D. Cords, H. Egiyan, T. Takeuchi, A. Yegneswaran, M. Osipenko, F. Sabatié, Kalvir S. Dhuga, M. Y. Gabrielyan, R. Dickson, R. J. Feuerbach, N. Guler, Inna Aznauryan, P. L. Cole, S. Barrow, L. Todor, D. Protopopescu, S. Pozdniakov, M. Garçon, Y. Ilieva, and B. Moreno
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Roper resonance, Meson production, 010308 nuclear & particles physics, State (functional analysis), 01 natural sciences, Helicity, Baryon, 0103 physical sciences, Pi, Isobar, 010306 general physics, Ground state
Abstract: The helicity amplitudes of the electroexcitation of the Roper resonance are extracted for $1.7l{Q}^{2}l4.5\phantom{\rule{0.3em}{0ex}}{\mathrm{GeV}}^{2}$ from recent high precision JLab-CLAS cross section and longitudinally polarized beam asymmetry data for ${\ensuremath{\pi}}^{+}$ electroproduction on protons at $W=1.15\ensuremath{-}1.69$ GeV. The analysis is made using two approaches, dispersion relations and a unitary isobar model, which give consistent ${Q}^{2}$ behavior of the helicity amplitudes for the ${\ensuremath{\gamma}}^{*}p\ensuremath{\rightarrow}$N(1440)P${}_{11}$ transition. It is found that the transverse helicity amplitude ${A}_{1/2}$, which is large and negative at ${Q}^{2}=0$, becomes large and positive at ${Q}^{2}\ensuremath{\simeq}2\phantom{\rule{0.3em}{0ex}}{\mathrm{GeV}}^{2}$, and then drops slowly with ${Q}^{2}$. The longitudinal helicity amplitude ${S}_{1/2}$, which was previously found from CLAS $\stackrel{\ensuremath{\rightarrow}}{e}p\ensuremath{\rightarrow}\mathit{ep}{\ensuremath{\pi}}^{0},\mathit{en}{\ensuremath{\pi}}^{+}$ data to be large and positive at ${Q}^{2}=0.4,0.65\phantom{\rule{0.3em}{0ex}}{\mathrm{GeV}}^{2}$, drops with ${Q}^{2}$. Available model predictions for ${\ensuremath{\gamma}}^{*}p\ensuremath{\rightarrow}$N(1440)P${}_{11}$ allow us to conclude that these results provide strong evidence in favor of N(1440)P${}_{11}$ as a first radial excitation of the $3q$ ground state. The results of the present paper also confirm the conclusion of our previous analysis for ${Q}^{2}l1$ GeV${}^{2}$ that the presentation of N(1440)P${}_{11}$ as a q$^{3}\mathrm{G}$ hybrid state is ruled out.
Published: 2008

40. First measurement of target and double spin asymmetries fore→p→→epπ0in the nucleon resonance region above theΔ(1232)

Author: F. X. Girod, L. Blaszczyk, Lorenzo Zana, N. Dashyan, H. Hakobyan, E. Munevar, B. Zhao, H. S. Jo, B. S. Ishkhanov, D. Keller, V. Crede, J. W. Price, William Brooks, C. Salgado, J. Kuhn, J. P. Santoro, E. Wolin, J. R. Calarco, J. P. Ball, Y. Prok, D. S. Carman, M. Yurov, G. Gavaliann, D. G. Crabb, J. Langheinrich, S. S. Stepanyan, C. Bookwalter, C. Butuceanu, Shifeng Chen, W. Kim, M. Khandaker, M. R. Niroula, H. Avakian, V. Gyurjyan, R. A. Schumacher, Barry Ritchie, S. A. Morrow, H. G. Juengst, M. Kossov, C. Djalali, D. Sharov, A. Fradi, S. Tkachenko, Maryam Moteabbed, L. Graham, F. Sabatié, P. Eugenio, J. Zhang, Bernhard Mecking, N. Benmouna, S. Dhamija, M. Ripani, I. I. Strakovsky, D. P. Watts, H. Bagdasaryan, A. Tkabladze, M. Taiuti, G. Niculescu, H. Egiyan, S. Bültmann, L. Todor, M. S. Saini, S. Strauch, M. D. Mestayer, A.V. Stavinsky, K. Mikhailov, Z. W. Zhao, T. A. Forest, R. W. Gothe, J. T. Goetz, M. J. Amaryan, G. Ricco, D. J. Tedeschi, E. L. Isupov, D. G. Jenkins, D. Protopopescu, S. Stepanyan, P. Collins, V. Sapunenko, M. MacCormick, I. Hleiqawi, A. Deur, Latifa Elouadrhiri, Michael L. Williams, N. Hassall, M. Bellis, J. Pierce, Kei Moriya, Avraham Klein, Michael Dugger, S. L. Careccia, I. Bedlinskiy, S. Park, C. A. Meyer, N. Markov, L. Casey, W. J. Briscoe, S. Pozdniakov, M. Garçon, G. S. Mutchler, G. V. Fedotov, C. Hanretty, S. Boiarinov, N. A. Baltzell, G. Rosner, B. L. Berman, S. E. Kuhn, E. Pasyuk, K. L. Giovanetti, P. Rossi, V. Kuznetsov, Friedrich Klein, G. E. Dodge, H. Y. Lu, B. B. Niczyporuk, Larry Weinstein, K. A. Griffioen, Brian Raue, E. De Sanctis, P. V. Degtyarenko, M. Battaglieri, Victor Mokeev, J. R. Johnstone, D. Doughty, N. Pivnyuk, L. Guo, P. Mattione, R. J. Feuerbach, L. Cheng, C. Paterson, M. Ungaro, Nikolay Shvedunov, L. El Fassi, I. Niculescu, R. A. Niyazov, D. P. Weygand, R. Bradford, D. Lawrence, Elton Smith, J. D. Kellie, J. Lachniet, D. I. Sober, R. De Masi, D. Schott, S. Niccolai, M. F. Vineyard, P. Stoler, R. Nasseripour, N. Kalantarians, J. Salamanca, K. Joo, Y. G. Sharabian, P. Coltharp, J. W C McNabb, A. V. Vlassov, W. Gohn, Z. Krahn, V. P. Kubarovsky, B. E. Stokes, R. G. Fersch, K. Hicks, A. Yegneswaran, M. M. Ito, O. Pogorelko, Y. Ilieva, N. Baillie, R. De Vita, B. McKinnon, P. L. Cole, D. Branford, S. Anefalos Pereira, G. Asryan, O. P. Dzyubak, M. Osipenko, M. Mirazita, J. M. Laget, N. Gevorgyan, P. Nadel-Turonski, Tsutomu Mibe, Michael Wood, K. Hafidi, P. Bosted, Gerard Gilfoyle, B. Moreno, D. Sokhan, V. S. Serov, K. Livingston, D. S. Dale, R. Dickson, A. I. Ostrovidov, K. Park, N. Guler, D. G. Ireland, Volker D. Burkert, A. S. Biselli, M. Guidal, M. Holtrop, C. E. Hyde-Wright, Sergey Kuleshov, and M. Nozar
Subjects: Physics, Nuclear and High Energy Physics, Roper resonance, Particle physics, Proton, 010308 nuclear & particles physics, media_common.quotation_subject, Coupling (probability), 01 natural sciences, Resonance (particle physics), Asymmetry, Nuclear physics, 0103 physical sciences, Invariant mass, 010306 general physics, Nucleon, Spin (physics), media_common
Abstract: DOI: http://dx.doi.org/10.1103/PhysRevC.78.045204 The exclusive channel polarized proton(polarized e,e prime p)pi0 was studied in the first and second nucleon resonance regions in the Q2 range from 0.187 to 0.770 GeV2 at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). Longitudinal target and beam-target asymmetries were extracted over a large range of center-of-mass angles of the pi0 and compared to the unitary isobar model MAID, the dynamic model by Sato and Lee, and the dynamic model DMT. A strong sensitivity to individual models was observed, in particular for the target asymmetry and in the higher invariant mass region. This data set, once included in the global fits of the above models, is expected to place strong constraints on the electrocoupling amplitudes A_{1/2} and S_{1/2} for the Roper resonance N(1400)P11, and the N(1535)S11 and N(1520)D13 states.
Published: 2008

41. Electroproduction ofϕ(1020)mesons at1.4⩽Q2⩽3.8GeV2measured with the CLAS spectrometer

Author: M. Guidal, R. Nasseripour, M. Holtrop, I. I. Strakovsky, R. J. Feuerbach, G. V. O'Rielly, Cynthia Marie Hadjidakis, B. Zhao, Z. W. Zhao, D. G. Jenkins, Alexei V. Klimenko, R. De Masi, A. Deur, Michael Dugger, H. O. Funsten, Michael Wood, K. Hafidi, N. Dashyan, B. E. Stokes, G. S. Adams, Barry Ritchie, P. L. Cole, B. M. Preedom, V. S. Serov, C. E. Hyde-Wright, S. McAleer, J. Langheinrich, S. S. Stepanyan, S. A. Philips, L. Blaszczyk, G. Ricco, J. Ball, F. W. Hersman, Sergey Kuleshov, Lorenzo Zana, J. P. Santoro, M. Bektasoglu, M. Nozar, M. Garçon, Elton Smith, M. Battaglieri, J. Salamanca, J. Lachniet, A. Tkabladze, Latifa Elouadrhiri, P. Coltharp, H. Hakobyan, F. Sabatié, H. S. Jo, K. Livingston, D. S. Dale, J. W C McNabb, J. R. Ficenec, N. A. Baltzell, V. Kuznetsov, R. Bradford, R. C. Minehart, Kei Moriya, C. A. Meyer, J. W. Price, M. M. Ito, S. Strauch, V. Mokeev, C. Salgado, L. Cheng, B. L. Berman, L. M. Qin, D. P. Watts, H. Egiyan, K. A. Griffioen, J. P. Cummings, V. Gyurjyan, G. V. Fedotov, S. A. Morrow, M. Anghinolfi, E. De Sanctis, V. P. Kubarovsky, D. Keller, Nikolay Shvedunov, Friedrich Klein, R. Dickson, James Mueller, C. Paterson, D. I. Sober, O. Pogorelko, C. Djalali, E. Munevar, D. P. Weygand, L. C. Smith, M. Kossov, L. C. Dennis, J. Zhang, B. E. Bonner, H. Avakian, Ji Li, M. Guillo, Brian Raue, S. Niccolai, I. Popa, S. Dhamija, N. Hassall, M. Bellis, H. Bagdasaryan, F. X. Girod, B. S. Ishkhanov, S. Park, R. Fatemi, N. Kalantarians, W. Gohn, A. V. Vlassov, J. R. Johnstone, D. Sharov, M. D. Mestayer, Y. G. Sharabian, Sylvain Bouchigny, J. Hardie, H. G. Juengst, J. Kuhn, L. El Fassi, C. Marchand, G. Audit, E. Wolin, H. Denizli, E. L. Isupov, R. De Vita, J. D. Kellie, L. Morand, Michael L. Williams, P. Rossi, N. Guler, William Brooks, Christian Weiss, A.V. Stavinsky, M. R. Niroula, R. W. Gothe, S. Boiarinov, W. Kim, M. Mirazita, W. J. Briscoe, L. Casey, G. Gavalian, C. Hanretty, S. Tkachenko, S. Anefalos Pereira, G. Niculescu, P. Nadel-Turonski, N. Benmouna, J. P. Ball, Tsutomu Mibe, Y. Prok, D. S. Carman, A. V. Skabelin, A. Cazes, Maryam Moteabbed, Hall Crannell, Bernhard Mecking, D. J. Tedeschi, M. Ripani, E. Pasyuk, V. Crede, Shifeng Chen, G. Rosner, K. V. Dharmawardane, J. R. Calarco, S. A. Dytman, I. Bedlinskiy, B. B. Niczyporuk, L. Guo, M. Ungaro, N. Pivnyuk, D. G. Crabb, R. A. Schumacher, M. Khandaker, S. Barrow, P. Mattione, M. S. Saini, P. Eugenio, M. Taiuti, K. Joo, G. S. Mutchler, Michael Vineyard, D. Cords, L. Graham, C. I O Gordon, A. Yegneswaran, M. Yurov, J. T. Goetz, S. Mehrabyan, S. Bültmann, V. Sapunenko, P. Collins, Dinko Pocanic, J. J. Melone, M. Osipenko, S. Procureur, T. A. Forest, C. Bookwalter, G. Riccardi, S. Stepanyan, S. E. Kuhn, Kalvir S. Dhuga, C. Butuceanu, J. Pierce, Avraham Klein, C. Tur, G. E. Dodge, L. Todor, H. Y. Lu, P. V. Degtyarenko, M. J. Amaryan, D. Protopopescu, M. MacCormick, I. Hleiqawi, S. Pozdniakov, I. Niculescu, D. Lawrence, S. L. Careccia, D. Schott, K. L. Giovanetti, Larry Weinstein, D. Doughty, D. Heddle, Y. Ilieva, B. Moreno, R. A. Miskimen, B. McKinnon, D. Branford, J. M. Laget, N. Gevorgyan, A. I. Ostrovidov, K. Park, D. G. Ireland, Volker D. Burkert, A. S. Biselli, Z. Krahn, N. Baillie, Laird Kramer, Gerard Gilfoyle, D. Sokhan, A. Fradi, N. Markov, G. Asryan, O. P. Dzyubak, R. A. Niyazov, P. Corvisiero, K. S. Egiyan, K. Mikhailov, P. Stoler, and K. Hicks
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Vector meson dominance, 01 natural sciences, Helicity, Gluon, 0103 physical sciences, Exponent, Vector meson, 010306 general physics, Nucleon, Exchange model
Abstract: Electroproduction of exclusive \ensuremath{\phi} vector mesons has been studied with the CLAS detector in the kinematic range $1.4\ensuremath{\leqslant}{Q}^{2}\ensuremath{\leqslant}3.8$ GeV${}^{2},0.0\ensuremath{\leqslant}{t}^{'}\ensuremath{\leqslant}3.6$ GeV${}^{2}$, and $2.0\ensuremath{\leqslant}W\ensuremath{\leqslant}3.0$ GeV. The scaling exponent for the total cross section as $1/({Q}^{2}+{M}_{\ensuremath{\phi}}^{2}){}^{n}$ was determined to be $n=2.49\ifmmode\pm\else\textpm\fi{}0.33$. The slope of the four-momentum transfer ${t}^{'}$ distribution is ${b}_{\ensuremath{\phi}}=0.98\ifmmode\pm\else\textpm\fi{}0.17$ GeV${}^{\ensuremath{-}2}$. Under the assumption of $s$-channel helicity conservation, we determine the ratio of longitudinal to transverse cross sections to be $R=0.86\ifmmode\pm\else\textpm\fi{}0.24$. A two-gluon exchange model is able to reproduce the main features of the data.
Published: 2008

42. Ratios ofN15/C12andHe4/C12inclusive electroproduction cross sections in the nucleon resonance region

Author: K. S. Egiyan, L. Guo, K. Mikhailov, Calarco, P. Stoler, K. Hicks, Susan Taylor, M. Ungaro, C. D. Keith, J. Donnelly, G. Asryan, O. P. Dzyubak, R. A. Niyazov, H. Egiyan, P. Corvisiero, C. E. Hyde-Wright, Y. Ilieva, R. A. Miskimen, G. Ricco, M. Amarian, E. Wolin, B. Zhao, B. McKinnon, R. Fatemi, S. Strauch, Laird Kramer, K. Park, B. B. Niczyporuk, P. Dragovitsch, Nikolay Shvedunov, J. P. Ball, Y. Prok, D. S. Carman, K. Joo, L. M. Qin, R. Suleiman, D. Branford, N. Pivnyuk, Shifeng Chen, A. V. Vlassov, Sergey Kuleshov, J. Yun, D. Cords, M. Mirazita, D. G. Crabb, J. M. Laget, M. Bektasoglu, G. S. Mutchler, S. Niccolai, A. Yegneswaran, M. Battaglieri, Niroula, A. Fradi, M. Nozar, N. A. Baltzell, J. Hardie, P. Eugenio, H. G. Juengst, S. A. Morrow, R. De Vita, O. Pogorelko, C. Djalali, Kubarovsky, C. Paterson, Friedrich Klein, K. A. Griffioen, R. J. Feuerbach, N. Markov, K. Livingston, M. Klusman, M. Taiuti, A.V. Stavinsky, N. Kalantarians, Brian Raue, F. W. Hersman, R. Bradford, K. Lukashin, Marco A. Huertas, D. J. Tedeschi, J. Langheinrich, A. I. Ostrovidov, A. C S Lima, J. T. Goetz, J. Shaw, E. Polli, S. S. Stepanyan, Crede, S. A. Philips, P. Collins, D. G. Ireland, Michael Wood, K. Hafidi, I. Bedlinskiy, Batourine, Elton Smith, Gerard Gilfoyle, Mestayer, Volker D. Burkert, V. S. Serov, L. C. Dennis, A. S. Biselli, N. Guler, B. E. Bonner, H. Avakian, B. Carnahan, G. Gavalian, S. Tkachenko, M. Anghinolfi, N. Benmouna, M. Ripani, Kwangsoo Kim, J. Kuhn, J. Zhang, S Anefalos, R. W. Gothe, G. Riccardi, A. Cazes, James Mueller, J. W C McNabb, Maryam Moteabbed, Bernhard Mecking, J. D. Kellie, S. Barrow, C. Butuceanu, K. V. Dharmawardane, E. Pasyuk, H. Bagdasaryan, Mokeev, Cynthia Marie Hadjidakis, E. De Sanctis, P. D. Rubin, K. Y. Kim, Y. G. Sharabian, M. Guidal, S. A. Dytman, R. G. Fersch, Michael Dugger, H. O. Funsten, L. Todor, N. Baillie, D. I. Sober, D. Protopopescu, M. Holtrop, S. Pozdniakov, M. Garçon, Hong Lu, Sbr Ultmann, Dinko Pocanic, Sylvain Bouchigny, P. L. Cole, P. Rossi, S. E. Kuhn, M. Bellis, J. Lachniet, H. Denizli, A. Tkabladze, D. Rowntree, Sapunenko, R. S. Hakobyan, A. V. Skabelin, P. Nadel-Turonski, Tsutomu Mibe, R. C. Minehart, C. A. Meyer, G. V. Fedotov, B. E. Stokes, G. S. Adams, D. P. Weygand, U. Thoma, M. Khandaker, L. C. Smith, B. S. Ishkhanov, D. Doughty, D. Heddle, Gyurjyan, W. Kim, S. Stepanyan, G. Niculescu, M. MacCormick, I. Hleiqawi, G. Rosner, R. Nasseripour, P. Bosted, S. L. Careccia, K. L. Giovanetti, Larry Weinstein, P. Coltharp, M. M. Ito, M. Osipenko, F. Sabatié, M. Guillo, K. Beard, L. Elouadrhiri, A. Deur, W. K. Brooks, R. A. Schumacher, G. V. O'Rielly, E. Golovatch, L. Morand, T. A. Forest, J. Pierce, Avraham Klein, Z. W. Zhao, J. P. Cummings, Hall Crannell, M. Kossov, D. G. Jenkins, G. E. Dodge, P. V. Degtyarenko, S. McAleer, F. X. Girod, I. Niculescu, D. Lawrence, J. W. Price, R. De Masi, Ji Li, E. L. Isupov, Michael L. Williams, S. Boiarinov, Michael Vineyard, B. M. Preedom, Lorenzo Zana, J. P. Santoro, H. S. Jo, and C. Salgado
Subjects: Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Scattering, Hadron, Carbon-12, Deep inelastic scattering, 01 natural sciences, Nuclear physics, Baryon, Helium-4, 0103 physical sciences, Phenomenological model, Atomic physics, 010306 general physics, Nucleon
Abstract: The (W,Q{sup 2}) dependence of the ratio of inclusive electron scattering cross sections for {sup 15}N/{sup 12}C was determined in the kinematic ranges 0.8
Published: 2008

43. Polarized structure functionσLT'forH1(e→,e'K+)Λin the nucleon resonance region

Author: L. C. Dennis, B. E. Bonner, S. McAleer, F. X. Girod, L. Blaszczyk, H. Avakian, D. Sharov, D. Lawrence, P. Stoler, K. Hicks, K. S. Egiyan, Laird Kramer, D. Doughty, L. C. Smith, E. Munevar, V. Mokeev, K. Mikhailov, Elton Smith, J. Langheinrich, S. S. Stepanyan, S. A. Philips, W. J. Briscoe, E. Pasyuk, B. S. Ishkhanov, D. P. Watts, S. A. Dytman, R. A. Schumacher, P. Eugenio, D. Heddle, H. Egiyan, J. W. Price, M. F. Vineyard, G. Asryan, O. P. Dzyubak, R. A. Niyazov, P. Nadel-Turonski, Tsutomu Mibe, H. G. Juengst, P. Corvisiero, E. Wolin, M. Taiuti, M. Anghinolfi, M. Kossov, James Mueller, E. De Sanctis, M. R. Niroula, J. P. Ball, M. Battaglieri, Y. Ilieva, P. D. Rubin, Y. G. Sharabian, A.V. Stavinsky, D. S. Carman, Patrick Girard, W. Kim, T. A. Forest, G. Niculescu, J. Lachniet, D. I. Sober, R. J. Feuerbach, Michael Wood, A. I. Ostrovidov, V. Sapunenko, L. Casey, Dinko Pocanic, R. Bradford, K. Lukashin, D. J. Tedeschi, K. Park, C. Hanretty, S. Stepanyan, K. Hafidi, D. G. Crabb, J. Pierce, V. S. Serov, S. E. Kuhn, Avraham Klein, E. Anciant, B. E. Stokes, B. B. Niczyporuk, I. Bedlinskiy, G. Ricco, D. G. Ireland, B. Moreno, G. E. Dodge, H. Y. Lu, P. V. Degtyarenko, N. Pivnyuk, Volker D. Burkert, A. S. Biselli, G. Audit, C. E. Hyde-Wright, R. Fatemi, A. V. Vlassov, R. De Vita, Z. W. Zhao, V. Kuznetsov, K. Joo, S. Procureur, Maryam Moteabbed, B. Zhao, D. G. Jenkins, Bernhard Mecking, Z. Krahn, Shifeng Chen, D. Sayre, S. Strauch, P. Collins, D. Protopopescu, I. Niculescu, M. Khandaker, S. Pozdniakov, Sylvain Bouchigny, J. J. Manak, P. Rossi, N. Baillie, S. Anefalos Pereira, A. Fradi, C. Cetina, A. Shafi, P. Dragovitsch, P. Mattione, Friedrich Klein, Kwangsoo Kim, R. A. Miskimen, B. McKinnon, V. P. Kubarovsky, G. Riccardi, J. Salamanca, Sergey Kuleshov, M. Osipenko, R. De Masi, Brian Raue, D. Branford, M. Mirazita, J. M. Laget, J. W C McNabb, S. A. Morrow, C. Djalali, G. S. Mutchler, M. Bektasoglu, S. Niccolai, F. Sabatié, N. Gevorgyan, C. Butuceanu, K. Beard, F. W. Hersman, N. A. Baltzell, J. T. Goetz, K. Livingston, D. S. Dale, N. Markov, O. Pogorelko, P. Coltharp, V. Crede, K. A. Griffioen, R. Dickson, J. Hardie, M. J. Amaryan, Kalvir S. Dhuga, P. Ambrozewicz, Gerard Gilfoyle, M. Nozar, D. Sokhan, M. MacCormick, M. Bellis, I. Hleiqawi, M. M. Ito, S. L. Careccia, J. Kuhn, R. W. Gothe, G. Gavalian, N. Guler, J. R. Calarco, G. A. Peterson, S. Simionatto, J. D. Kellie, S. Taylor, S. Tkachenko, K. Y. Kim, K. L. Giovanetti, B. Asavapibhop, J. P. Santoro, Roy Thompson, Larry Weinstein, S. Barrow, N. Benmouna, M. Ripani, M. Guidal, M. Guillo, L. Cheng, M. D. Mestayer, G. Rosner, R. Nasseripour, Nikolay Shvedunov, J. Hu, E. L. Isupov, L. Elouadrhiri, M. Holtrop, Michael L. Williams, S. Boiarinov, I. I. Strakovsky, B. M. Preedom, A. Deur, Lorenzo Zana, N. Kalantarians, H. Hakobyan, H. S. Jo, Gerald Feldman, Michael Dugger, W. K. Brooks, K. Wang, H. O. Funsten, C. Salgado, B. L. Berman, L. M. Qin, C. Paterson, Thierry Auger, M. Garçcon, J. R. Johnstone, V. Gyurjyan, J. Zhang, H. Bagdasaryan, L. Guo, M. Ungaro, A. Tkabladze, J. Yun, D. Cords, L. El Fassi, A. Yegneswaran, P. L. Cole, Y. Prok, Barry Ritchie, R. C. Minehart, Kei Moriya, C. A. Meyer, G. V. Fedotov, D. P. Weygand, A. V. Skabelin, and N. Dashyan
Subjects: Physics, Nuclear and High Energy Physics, Angular range, 010308 nuclear & particles physics, Hydrogen-1, Structure function, Hyperon, Sigma, Resonance, Lambda, 01 natural sciences, 0103 physical sciences, Atomic physics, Nuclear Experiment, 010306 general physics, Nucleon
Abstract: The first measurements of the polarized structure function {sigma}{sub LT{sup '}} for the reaction {sup 1}H(e-vector,e{sup '}K{sup +}){lambda} in the nucleon resonance region are reported. Measurements are included from threshold up to W=2.05 GeV for central values of Q{sup 2} of 0.65 and 1.00 GeV{sup 2}, and nearly the entire kaon center-of-mass angular range. {sigma}{sub LT{sup '}} is the imaginary part of the longitudinal-transverse response and is expected to be sensitive to interferences between competing intermediate s-channel resonances, as well as resonant and nonresonant processes. The results for {sigma}{sub LT{sup '}} are comparable in magnitude to previously reported results from CLAS for {sigma}{sub LT}, the real part of the same response. An intriguing sign change in {sigma}{sub LT{sup '}} is observed in the high Q{sup 2} data at W{approx_equal}1.9 GeV. Comparisons to several existing model predictions are shown.
Published: 2008

44. Measurement ofep→epπ0beam spin asymmetries above the resonance region

Author: R. De Masi, M. Garçon, B. Zhao, M. J. Amaryan, P. Ambrozewicz, M. Anghinolfi, G. Asryan, H. Avakian, H. Bagdasaryan, N. Baillie, J. Ball, J. P. Ball, N. A. Baltzell, V. Batourine, M. Battaglieri, I. Bedlinskiy, M. Bellis, N. Benmouna, B. L. Berman, P. Bertin, A. S. Biselli, L. Blaszczyk, S. Bouchigny, S. Boiarinov, R. Bradford, D. Branford, W. J. Briscoe, W. K. Brooks, S. Bültmann, V. D. Burkert, C. Butuceanu, J. R. Calarco, S. L. Careccia, D. S. Carman, L. Casey, S. Chen, L. Cheng, P. L. Cole, P. Collins, P. Coltharp, D. Crabb, V. Crede, N. Dashyan, E. De Sanctis, R. De Vita, P. V. Degtyarenko, A. Deur, K. V. Dharmawardane, R. Dickson, C. Djalali, G. E. Dodge, J. Donnelly, D. Doughty, M. Dugger, O. P. Dzyubak, H. Egiyan, K. S. Egiyan, L. El Fassi, L. Elouadrhiri, P. Eugenio, G. Fedotov, G. Feldman, A. Fradi, H. Funsten, G. Gavalian, G. P. Gilfoyle, K. L. Giovanetti, F. X. Girod, J. T. Goetz, A. Gonenc, R. W. Gothe, K. A. Griffioen, M. Guidal, N. Guler, L. Guo, V. Gyurjyan, K. Hafidi, H. Hakobyan, C. Hanretty, F. W. Hersman, K. Hicks, I. Hleiqawi, M. Holtrop, C. E. Hyde-Wright, Y. Ilieva, D. G. Ireland, B. S. Ishkhanov, E. L. Isupov, M. M. Ito, D. Jenkins, H. S. Jo, J. R. Johnstone, K. Joo, H. G. Juengst, N. Kalantarians, J. D. Kellie, M. Khandaker, W. Kim, A. Klein, F. J. Klein, A. V. Klimenko, M. Kossov, Z. Krahn, L. H. Kramer, V. Kubarovsky, J. Kuhn, S. E. Kuhn, S. V. Kuleshov, J. Lachniet, J. M. Laget, J. Langheinrich, D. Lawrence, T. Lee, K. Livingston, H. Y. Lu, M. MacCormick, N. Markov, P. Mattione, M. Mazouz, B. McKinnon, B. A. Mecking, M. D. Mestayer, C. A. Meyer, T. Mibe, B. Michel, K. Mikhailov, M. Mirazita, R. Miskimen, V. Mokeev, B. Moreno, K. Moriya, S. A. Morrow, M. Moteabbed, E. Munevar, G. S. Mutchler, P. Nadel-Turonski, R. Nasseripour, S. Niccolai, G. Niculescu, I. Niculescu, B. B. Niczyporuk, M. R. Niroula, R. A. Niyazov, M. Nozar, M. Osipenko, A. I. Ostrovidov, K. Park, E. Pasyuk, C. Paterson, S. Anefalos Pereira, J. Pierce, N. Pivnyuk, D. Pocanic, O. Pogorelko, S. Pozdniakov, J. W. Price, S. Procureur, Y. Prok, D. Protopopescu, B. A. Raue, G. Ricco, M. Ripani, B. G. Ritchie, F. Ronchetti, G. Rosner, P. Rossi, F. Sabatié, J. Salamanca, C. Salgado, J. P. Santoro, V. Sapunenko, R. A. Schumacher, V. S. Serov, Y. G. Sharabian, D. Sharov, N. V. Shvedunov, E. S. Smith, L. C. Smith, D. I. Sober, D. Sokhan, A. Stavinsky, S. Stepanyan, S. S. Stepanyan, B. E. Stokes, P. Stoler, I. I. Strakovsky, S. Strauch, M. Taiuti, D. J. Tedeschi, A. Tkabladze, S. Tkachenko, C. Tur, M. Ungaro, M. F. Vineyard, A. V. Vlassov, E. Voutier, D. P. Watts, L. B. Weinstein, D. P. Weygand, M. Williams, E. Wolin, M. H. Wood, A. Yegneswaran, L. Zana, J. Zhang, and Z. W. Zhao
Subjects: Physics, Nuclear and High Energy Physics, Photon, Spectrometer, 010308 nuclear & particles physics, media_common.quotation_subject, Parton, 01 natural sciences, Asymmetry, Nuclear physics, Formalism (philosophy of mathematics), Amplitude, 0103 physical sciences, Cathode ray, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, media_common
Abstract: The beam spin asymmetry (BSA) in the exclusive reaction ep->ep pi0 was measured with the CEBAF 5.77 GeV polarized electron beam and Large Acceptance Spectrometer(CLAS). The xB, Q2, t and phi dependences of the pi0 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 non-zero 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

45. Probing the short range behavior of nuclei with high PT photo- and electro-nuclear reactions

Author: J. M. Laget
Subjects: Baryon, Physics, Quark, Coupling constant, Particle physics, Meson, High Energy Physics::Phenomenology, Nuclear Theory, Hadron, Virtual particle, Few-body systems, Nuclear Experiment, Nucleon
Abstract: The extensive study of nuclei with hadronic probes, as well as with electromagnetic probes, has led us to an economical and consistent picture of nuclei made of nucleons, which interact by exchanging mesons. It relies on the description of baryons as a small core, of radius 0.5 fm, surrounded by a meson cloud which is polarized by the vicinity of the other baryons. We have also reached a good understanding of intermediate energy reactions, induced in few body systems, in terms of complex combinations of elementary processes, which can be independently single out by a judiciable choice of the kinematics and the probe. Up to now, there is no need to explicitely introduce quark degrees of freedom. Of course, there is no doubt that ultimately nuclei are made of quarks. But, in this picture, they are hidden in the various meson-baryon coupling constants and form-factors. At which scale will they start to show up is still an open question.
Published: 2008

46. Pion production off light nuclei

Author: J. M. Laget
Subjects: Nuclear physics, Physics, Matrix (mathematics), Photon, Pion, Deuterium, Scattering, Virtual particle, Nuclear Experiment, Absorption (electromagnetic radiation), Spectral line
Abstract: The analysis of pion photoproduction reactions induced on deuterium is briefly summarized : the deviations from the multiple scattering series are a possible way to study the NΔ interaction. These two-body matrix elements are used to analyse the inclusive (total absorption of real or virtual photons) or one-arm (particle spectra) reactions induced on light nuclei. It is shown that the incoming (real or virtual) photon interacts mainly with the one-body and the two-body currents alone.
Published: 2008

47. Light Vector Mesons in the Nuclear Medium

Author: V. Crede, S. McAleer, L. Blaszczyk, J. R. Calarco, B. L. Berman, E. De Sanctis, S. Tkachenko, M. Taiuti, R. A. Schumacher, Michael Wood, A. I. Ostrovidov, G. Asryan, C. I O Gordon, K. Hafidi, K. Park, C. Paterson, J. W. Price, O. P. Dzyubak, R. A. Niyazov, V. S. Serov, L. C. Dennis, D. G. Ireland, B. G. Ritchie, B. E. Stokes, J. Kuhn, M. R. Niroula, Cynthia Marie Hadjidakis, M. J. Amaryan, H. Avakian, M. MacCormick, I. Hleiqawi, Volker D. Burkert, G. S. Adams, S. L. Careccia, A. S. Biselli, S. Stepanyan, D. Sharov, A. V. Vlassov, Philip L. Cole, Larry Weinstein, J. Pierce, Avraham Klein, Chaden Djalali, K.H. Hicks, D. J. Tedeschi, K. Joo, Sylvain Bouchigny, G. S. Mutchler, Michael Dugger, W. Kim, Gerard Gilfoyle, D. Sokhan, H. S. Jo, K. S. Egiyan, J. Hardie, Friedrich Klein, J. P. Cummings, Laird Kramer, K. Livingston, S. A. Dytman, W. K. Brooks, B. Carnahan, S. Niccolai, H. O. Funsten, P. Collins, Ulrich Mosel, Z. W. Zhao, I. Bedlinskiy, H. G. Juengst, G. Niculescu, R. Nasseripour, K. Mikhailov, R. A. Miskimen, B. McKinnon, H. Hakobyan, S. Anefalos Pereira, D. G. Jenkins, P. Coltharp, Hall Crannell, A.V. Stavinsky, P. Eugenio, R. W. Gothe, V. Sapunenko, M. Bektasoglu, C. Salgado, Dinko Pocanic, M. M. Ito, D. Branford, V. Gyurjyan, P. Khetarpal, A. Fradi, M. Holtrop, M. Kossov, J. M. Laget, D. P. Weygand, Y. Ilieva, V. P. Kubarovsky, R. De Vita, L. C. Smith, E. Munevar, G. E. Dodge, B. S. Ishkhanov, P. Nadel-Turonski, H. Bagdasaryan, P. V. Degtyarenko, N. Guler, S. E. Kuhn, Federico Ronchetti, J. J. Melone, K. Moriya, C. Hanretty, I. Niculescu, D. Lawrence, J. D. Kellie, Victor Mokeev, J. R. Johnstone, L. Guo, M. Ungaro, Latifa Elouadrhiri, G. Rosner, J. Lachniet, A. Tkabladze, M. Guidal, A. Yegneswaran, R. C. Minehart, S. Barrow, C. Tur, P. Rossi, J. Langheinrich, S. S. Stepanyan, E. Pasyuk, J. Zhang, C. A. Meyer, S. Mehrabyan, F. X. Girod, Baile Zhang, G. V. Fedotov, G. Gavalian, R. S. Hakobyan, R. Dickson, M. Ripani, L. El Fassi, D. Doughty, Z. Krahn, N. Benmouna, G. Riccardi, B. A. Raue, M. Osipenko, C. Butuceanu, Tsutomu Mibe, L. Cheng, Shifeng Chen, N. Baillie, Daniel S. Carman, F. Sabatié, Nikolay Shvedunov, K. L. Giovanetti, S. V. Kuleshov, D. Protopopescu, G. Ricco, S. Pozdniakov, M. Garçon, E. Wolin, C. E. Hyde-Wright, O. Pogorelko, J. Ball, N. Kalantarians, M. Khandaker, D. G. Crabb, M. Nozar, B. Zhao, H. Denizli, H. Y. Lu, J. T. Goetz, F. W. Hersman, M. Mirazita, Elton Smith, N. Dashyan, James Mueller, Alexei V. Klimenko, Y. Prok, I. I. Strakovsky, Y. G. Sharabian, P. Muehlich, A. Deur, Ji Li, M. D. Mestayer, R. J. Feuerbach, E. L. Isupov, Michael L. Williams, Maryam Moteabbed, Bernhard Mecking, K. V. Dharmawardane, S. Boiarinov, B. M. Preedom, Lorenzo Zana, J. P. Santoro, M. Battaglieri, D. P. Watts, H. Egiyan, Gerald Feldman, N. A. Baltzell, N. Markov, R. Bradford, K. A. Griffioen, N. Hassall, M. Bellis, J. Salamanca, P. Mattione, J. W C McNabb, M. Anghinolfi, L. Casey, B. B. Niczyporuk, Michael Vineyard, N. Pivnyuk, W. J. Briscoe, L. Todor, S. A. Morrow, S. Strauch, P. Ambrozewicz, P. Stoler, D. I. Sober, Thomas Jefferson National Accelerator Facility (Jefferson Lab), 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 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: Nuclear and High Energy Physics, Particle physics, Rho meson, Meson, Nuclear Theory, FOS: Physical sciences, light vector mesons, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 7. Clean energy, 01 natural sciences, chiral symmetry, Spectral line, Nuclear physics, ENHANCEMENT, CLAS, 0103 physical sciences, 11.30.Rd, 14.40.Cs, 24.85.+p, QCD SUM-RULES, Invariant mass, RHO-MESON, Nuclear Experiment (nucl-ex), 010306 general physics, in-medium modifications, Nuclear Experiment, Physics, AU COLLISIONS, QCD sum rules, CEBAF, 010308 nuclear & particles physics, QCD SUM-RULES, RHO-MESON, SPECTRAL-FUNCTION, AU COLLISIONS, OMEGA-MESONS, MATTER, CLAS, ENHANCEMENT, SYSTEM, CEBAF, Nuclear matter, SPECTRAL-FUNCTION, Deuterium, Mass spectrum, High Energy Physics::Experiment, MATTER, SYSTEM, OMEGA-MESONS
Abstract: The light vector mesons ($\rho$, $\omega$, and $\phi$) were produced in deuterium, carbon, titanium, and iron targets in a search for possible in-medium modifications to the properties of the $\rho$ meson at normal nuclear densities and zero temperature. The vector mesons were detected with the CEBAF Large Acceptance Spectrometer (CLAS) via their decays to $e^{+}e^{-}$. The rare leptonic decay was chosen to reduce final-state interactions. A combinatorial background was subtracted from the invariant mass spectra using a well-established event-mixing technique. The $\rho$ meson mass spectrum was extracted after the $\omega$ and $\phi$ signals were removed in a nearly model-independent way. Comparisons were made between the $\rho$ mass spectra from the heavy targets ($A > 2$) with the mass spectrum extracted from the deuterium target. With respect to the $\rho$-meson mass, we obtain a small shift compatible with zero. Also, we measure widths consistent with standard nuclear many-body effects such as collisional broadening and Fermi motion., Comment: 15 pages, 18 figures, 3 tables
Published: 2008

48. Bayesian analysis of pentaquark signals from CLAS data

Author: W. Kim, P. Coltharp, L. C. Smith, E. Munevar, G. Niculescu, B. S. Ishkhanov, M. R. Niroula, E. Wolin, D. P. Watts, A. V. Vlassov, Lorenzo Zana, N. Markov, Gerard Gilfoyle, H. Avakian, D. Sharov, R. De Vita, A. Fradi, F. X. Girod, L. Blaszczyk, D. Sokhan, H. Hakobyan, H. S. Jo, Gerald Feldman, D. Doughty, Chaden Djalali, J. Kuhn, Michael Dugger, B. Zhao, W. J. Briscoe, G. E. Dodge, H. Y. Lu, S. Anefalos Pereira, Federico Ronchetti, M. Kossov, H. O. Funsten, J. P. Ball, Y. Prok, E. Pasyuk, B. E. Stokes, J. P. Santoro, D. S. Carman, C. Salgado, B. L. Berman, C. E. Hyde-Wright, Atilla Gonenc, P. V. Degtyarenko, Sylvain Bouchigny, K. Joo, Y. Ilieva, N. Hassall, M. Bellis, G. Ricco, J. W. Price, E. De Sanctis, P. Rossi, Laird Kramer, V. Kuznetsov, J. Lachniet, D. I. Sober, Z. Krahn, D. G. Crabb, F. W. Hersman, Sergey Kuleshov, Friedrich Klein, Brian Raue, N. Dashyan, Michael Wood, M. Nozar, M. Ripani, M. D. Mestayer, P. Eugenio, N. Baillie, K. Hafidi, M. Taiuti, Z. W. Zhao, C. Paterson, I. Niculescu, E. L. Isupov, V. Crede, R. A. Miskimen, B. McKinnon, D. G. Jenkins, Michael L. Williams, J. Langheinrich, A. I. Ostrovidov, D. Lawrence, M. Osipenko, V. S. Serov, N. A. Baltzell, S. S. Stepanyan, D. G. Ireland, S. Boiarinov, D. Branford, J. D. Kellie, J. R. Calarco, K. A. Griffioen, Volker D. Burkert, A. S. Biselli, P. Collins, M. Mirazita, V. Batourine, M. Khandaker, G. Rosner, R. Nasseripour, G. Gavalian, J. M. Laget, J. Donnelly, S. Tkachenko, N. Gevorgyan, R. De Masi, K. Park, F. Sabatié, G. Asryan, N. Benmouna, S. Procureur, Maryam Moteabbed, Bernhard Mecking, Michael Vineyard, B. Moreno, R. A. Schumacher, R. W. Gothe, L. Cheng, O. P. Dzyubak, C. Butuceanu, Nikolay Shvedunov, S. Strauch, M. Guidal, M. MacCormick, D. Protopopescu, I. Hleiqawi, M. Battaglieri, S. L. Careccia, G. S. Mutchler, S. Pozdniakov, M. Garçon, R. Bradford, K. L. Giovanetti, N. Kalantarians, Larry Weinstein, K. Livingston, M. Holtrop, S. Niccolai, R. Dickson, N. Guler, S. Stepanyan, H. G. Juengst, J. Pierce, Avraham Klein, A.V. Stavinsky, K. S. Egiyan, D. J. Tedeschi, V. Gyurjyan, I. Bedlinskiy, K. Mikhailov, J. Zhang, H. Bagdasaryan, L. Guo, M. Ungaro, P. Stoler, R. A. Niyazov, A. Yegneswaran, P. Nadel-Turonski, Tsutomu Mibe, C. Hanretty, Barry Ritchie, Victor Mokeev, J. R. Johnstone, P. L. Cole, A. Tkabladze, Latifa Elouadrhiri, L. El Fassi, Kei Moriya, C. A. Meyer, V. Sapunenko, G. V. Fedotov, S. A. Morrow, P. Ambrozewicz, D. P. Weygand, J. Salamanca, L. Casey, W. Gohn, C. Tur, B. B. Niczyporuk, N. Pivnyuk, A. Deur, W. K. Brooks, M. Anghinolfi, Y. G. Sharabian, Shifeng Chen, P. Mattione, J. T. Goetz, V. P. Kubarovsky, O. Pogorelko, Institut de Physique Nucléaire d'Orsay (IPNO), 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), 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 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)
Subjects: Quark, Particle physics, Bayesian probability, FOS: Physical sciences, General Physics and Astronomy, Physics and Astronomy(all), 01 natural sciences, Bayesian, Particle identification, High Energy Physics - Phenomenology (hep-ph), CLAS, 0103 physical sciences, Feature (machine learning), Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, pentaquark, Physics, 010308 nuclear & particles physics, Hyperon, Probability and statistics, Fermion, 13.60.Rj, 12.39.Mk, 14.20.Jn, 14.80.-j, 02.50.-r, 02.70.Uu, Pentaquark, High Energy Physics - Phenomenology, Physics - Data Analysis, Statistics and Probability, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], Data Analysis, Statistics and Probability (physics.data-an)
Abstract: We examine the results of two measurements by the CLAS collaboration, one of which claimed evidence for a $\Theta^{+}$ pentaquark, whilst the other found no such evidence. The unique feature of these two experiments was that they were performed with the same experimental setup. Using a Bayesian analysis we find that the results of the two experiments are in fact compatible with each other, but that the first measurement did not contain sufficient information to determine unambiguously the existence of a $\Theta^{+}$. Further, we suggest a means by which the existence of a new candidate particle can be tested in a rigorous manner., Comment: 5 pages, 3 figures
Published: 2008

49. Cross sections and beam asymmetries fore→p→enπ+in the nucleon resonance region for1.7⩽Q2⩽4.5GeV2

Author: R. Fatemi, A. V. Vlassov, T. Lee, H. G. Juengst, A. Fradi, R. De Vita, A.V. Stavinsky, N. Markov, N. Hassall, B. Zhao, D. J. Tedeschi, S. Park, Sylvain Bouchigny, K. Hafnaoui, K. Livingston, D. S. Dale, G. Rosner, R. Nasseripour, I. Bedlinskiy, S. Anefalos Pereira, P. Rossi, E. Wolin, R. Dickson, Ji Li, J. P. Ball, Y. Prok, F. W. Hersman, V. Kuznetsov, J. P. Cummings, V. Sapunenko, Dinko Pocanic, C. Hanretty, N. Guler, S. McAleer, F. X. Girod, L. Blaszczyk, D. G. Ireland, V. Crede, S. E. Kuhn, M. Osipenko, F. Sabatié, J. Lachniet, H. Denizli, A. Tkabladze, J. R. Johnstone, M. Kossov, J. R. Calarco, D. G. Crabb, D. Rowntree, J. Donnelly, G. Asryan, O. P. Dzyubak, R. A. Niyazov, A. I. Ostrovidov, A. C S Lima, R. Suleiman, I. Popa, G. S. Mutchler, L. Guo, G. E. Dodge, H. Y. Lu, M. Ungaro, D. Doughty, M. D. Mestayer, S. Niccolai, E. De Sanctis, Volker D. Burkert, A. S. Biselli, E. L. Isupov, C. Tur, M. Guillo, D. Heddle, W. Gohn, M. Guidal, J. Hardie, Z. Krahn, J. Kuhn, P. L. Cole, S. Barrow, Elton Smith, Friedrich Klein, M. Yurov, Kalvir S. Dhuga, Michael L. Williams, P. V. Degtyarenko, N. Baillie, M. Anghinolfi, James Mueller, A. V. Skabelin, L. Todor, D. Protopopescu, S. Mehrabyan, D. I. Sober, S. Pozdniakov, M. Garçon, J. Yun, D. Cords, S. S. Stepanyan, S. Boiarinov, P. D. Rubin, Y. G. Sharabian, A. Yegneswaran, R. A. Miskimen, Brian Raue, B. McKinnon, Atilla Gonenc, R. C. Minehart, Kei Moriya, C. A. Meyer, J. W. Price, T. Takeuchi, M. Holtrop, I. Niculescu, C. Bookwalter, G. V. Fedotov, W. Kim, G. Niculescu, G. Gavalian, Laird Kramer, G. Riccardi, D. Lawrence, Baile Zhang, Shifeng Chen, S. Dhamija, J. Shaw, P. Corvisiero, S. Tkachenko, L. El Fassi, D. Branford, Michael Wood, R. De Masi, B. E. Stokes, K. Hafidi, C. Butuceanu, D. Keller, D. Schott, G. S. Adams, N. A. Baltzell, V. Gyurjyan, N. Benmouna, M. Ripani, K. Joo, N. Dashyan, P. Mattione, D. P. Weygand, M. S. Saini, M. Mirazita, J. M. Laget, V. S. Serov, R. W. Gothe, Y. Ilieva, N. Gevorgyan, Michael Vineyard, J. Zhang, P. Nadel-Turonski, Alexei V. Klimenko, L. Cheng, Tsutomu Mibe, B. M. Preedom, L. Elouadrhiri, J. Langheinrich, K. Y. Kim, Nikolay Shvedunov, J. T. Goetz, E. Polli, H. Bagdasaryan, Lorenzo Zana, J. P. Santoro, Barry Ritchie, S. A. Philips, M. Khandaker, P. Eugenio, M. Taiuti, G. V. O'Rielly, Z. W. Zhao, I. I. Strakovsky, P. Stoler, J. D. Kellie, S. A. Morrow, V. P. Kubarovsky, V. Mokeev, R. A. Schumacher, B. Moreno, Gerard Gilfoyle, G. Ricco, C. Djalali, H. Hakobyan, H. S. Jo, Gerald Feldman, K. Hicks, O. Pogorelko, A. Deur, D. G. Jenkins, Federico Ronchetti, L. C. Dennis, L. Graham, P. Collins, B. E. Bonner, J. J. Melone, C. Salgado, D. Sokhan, K. Park, Daniel S. Carman, M. J. Amaryan, K. S. Egiyan, C. I O Gordon, N. Kalantarians, H. Avakian, W. K. Brooks, M. MacCormick, I. Hleiqawi, C. E. Hyde-Wright, D. Sharov, P. Ambrozewicz, K. Mikhailov, S. Bültmann, L. Morand, T. A. Forest, Cynthia Marie Hadjidakis, S. L. Careccia, Sergey Kuleshov, S. Stepanyan, K. L. Giovanetti, J. Pierce, Avraham Klein, Larry Weinstein, M. Bektasoglu, M. Nozar, Michael Dugger, H. O. Funsten, W. J. Briscoe, E. Pasyuk, S. A. Dytman, J. Salamanca, J. W C McNabb, L. Casey, B. B. Niczyporuk, N. Pivnyuk, V. Batourine, M. Battaglieri, L. C. Smith, E. Munevar, B. S. Ishkhanov, B. L. Berman, R. Bradford, B. A. Mecking, K. Lukashin, L. M. Qin, R. S. Hakobyan, K. A. Griffioen, C. Paterson, M. Klusman, D. P. Watts, M. R. Niroula, E. Golovatch, M. Bellis, S. Strauch, H. Egiyan, A. Cazes, Maryam Moteabbed, P. Coltharp, K. V. Dharmawardane, M. Y. Gabrielyan, R. J. Feuerbach, M. M. Ito, and Inna Aznauryan
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Meson, 010308 nuclear & particles physics, Resonance, 01 natural sciences, Excited state, Isospin, 0103 physical sciences, Production (computer science), Invariant mass, Sensitivity (control systems), Atomic physics, 010306 general physics, Nucleon
Abstract: The exclusive electroproduction process $\stackrel{\ensuremath{\rightarrow}}{e}p\ensuremath{\rightarrow}{e}^{'}n{\ensuremath{\pi}}^{+}$ was measured in the range of the photon virtuality ${Q}^{2}=1.7\text{\ensuremath{-}}4.5 {\mathrm{GeV}}^{2}$, and the invariant mass range for the $n{\ensuremath{\pi}}^{+}$ system of $W=1.15\text{\ensuremath{-}}1.7 \mathrm{GeV}$ using the CEBAF Large Acceptance Spectrometer. For the first time, these kinematics are probed in exclusive ${\ensuremath{\pi}}^{+}$ production from protons with nearly full coverage in the azimuthal and polar angles of the $n{\ensuremath{\pi}}^{+}$ center-of-mass system. The $n{\ensuremath{\pi}}^{+}$ channel has particular sensitivity to the isospin \textonehalf{} excited nucleon states, and together with the $p{\ensuremath{\pi}}^{0}$ final state will serve to determine the transition form factors of a large number of resonances. The largest discrepancy between these results and present modes was seen in the ${\ensuremath{\sigma}}_{{\mathit{LT}}^{'}}$ structure function. In this experiment, 31,295 cross section and 4,184 asymmetry data points were measured. Because of the large volume of data, only a reduced set of structure functions and Legendre polynomial moments can be presented that are obtained in model-independent fits to the differential cross sections.
Published: 2008

50. Measurement of Deeply Virtual Compton Scattering Beam-Spin Asymmetries

Author: G. Niculescu, Gerard Gilfoyle, K. Livingston, L. Blaszczyk, S. Tkachenko, I. I. Strakovsky, A. Deur, D. Sokhan, J. Donnelly, G. Asryan, O. P. Dzyubak, A. V. Vlassov, M. Taiuti, K. S. Egiyan, K. Mikhailov, T. Lee, Atilla Gonenc, G. E. Dodge, R. W. Gothe, J. W. Price, M. Guidal, P. Rossi, R. Dickson, V. Crede, D. Doughty, P. V. Degtyarenko, Daniel S. Carman, Alexei V. Klimenko, J. R. Calarco, M. Mazouz, R. Miskimen, J. Salamanca, Lorenzo Zana, J. Kuhn, M. Ripani, Philip L. Cole, J. P. Santoro, Y. Prok, Z. Krahn, Hovanes Egiyan, B. A. Raue, D. P. Watts, Barry Ritchie, O. Pogorelko, M. Khandaker, V. Batourine, C. Butuceanu, G. Ricco, I. Niculescu, R. A. Niyazov, H. Y. Lu, Friedrich Klein, D. Lawrence, E. Wolin, Z. W. Zhao, N. Markov, Elton Smith, Gerald Feldman, B. McKinnon, J. Ball, S. A. Morrow, N. Baillie, R. De Masi, J. P. Ball, M. Nozar, P. Eugenio, B. Zhao, D. Protopopescu, C. E. Hyde, S. Pozdniakov, M. Garçon, D. Branford, P. Stoler, Michael Wood, R. A. Schumacher, E. De Sanctis, M. J. Amaryan, J. M. Laget, K. Hafidi, P. Ambrozewicz, M. MacCormick, Y. Ilieva, B. Michel, V. S. Serov, D. G. Crabb, J. Langheinrich, E. Voutier, S. S. Stepanyan, E. Pasyuk, R. De Vita, I. Hleiqawi, M. Osipenko, M. Kossov, S. L. Careccia, B. E. Stokes, N. Guler, Sylvain Bouchigny, S. Bültmann, Tsutomu Mibe, M. Anghinolfi, M. R. Niroula, N. Dashyan, F. W. Hersman, L. C. Smith, E. Munevar, S. Stepanyan, L. Casey, K.H. Hicks, K. Joo, Y. G. Sharabian, Larry Weinstein, J. Pierce, Avraham Klein, Latifa Elouadrhiri, D. J. Tedeschi, B. L. Berman, B. S. Ishkhanov, I. Bedlinskiy, N. A. Baltzell, C. A. Meyer, V. P. Kubarovsky, G. V. Fedotov, Laird Kramer, P. Collins, David Jenkins, J. D. Kellie, B. B. Niczyporuk, K. L. Giovanetti, S. V. Kuleshov, C. Hanretty, M. Holtrop, C. Paterson, V. Sapunenko, Michael Vineyard, H. Avakian, D. Sharov, N. Pivnyuk, Dinko Pocanic, D. P. Weygand, W. J. Briscoe, H. S. Jo, K. A. Griffioen, A. I. Ostrovidov, K. Park, D. G. Ireland, S. E. Kuhn, M. D. Mestayer, Volker D. Burkert, A. S. Biselli, S. Niccolai, E. L. Isupov, Michael L. Williams, W. K. Brooks, S. Boiarinov, C. Tur, G. Rosner, P. Coltharp, Victor Mokeev, J. R. Johnstone, Shifeng Chen, J. Lachniet, M. M. Ito, L. Guo, P. Mattione, A. Tkabladze, J. T. Goetz, V. Gyurjyan, M. Mirazita, M. Ungaro, J. Zhang, F. X. Girod, S. Strauch, L. El Fassi, R. Nasseripour, P. Nadel-Turonski, D. I. Sober, G. S. Mutchler, H. Bagdasaryan, M. Bellis, S. Procureur, Maryam Moteabbed, Bernhard Mecking, K. V. Dharmawardane, G. Gavalian, M. Battaglieri, N. Benmouna, R. Bradford, Chaden Djalali, Michael Dugger, H. O. Funsten, K. Moriya, Carlos A. Salgado, L. Cheng, F. Sabatié, Nikolay Shvedunov, A. Yegneswaran, N. Kalantarians, H. G. Juengst, H. Hakobyan, S. Anefalos Pereira, A.V. Stavinsky, W. Kim, 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, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Physique 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), CLAS, 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), and 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)
Subjects: Quark, Particle physics, Photon, Proton, media_common.quotation_subject, HERA, General Physics and Astronomy, Parton, Kinematics, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, Asymmetry, Nuclear physics, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], PARTON DISTRIBUTIONS, NUCLEON, HERA, NUCLEON, 010306 general physics, Nuclear Experiment, media_common, Physics, 010308 nuclear & particles physics, Compton scattering, 12.40.Vv,13.40.Gp,13.60.Fz,13.60.Hb,13.60.-r,14.20.Dh,24.85.+p, PARTON DISTRIBUTIONS, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], High Energy Physics::Experiment, Nucleon
Abstract: 1 tex file (6 pages), 4 (eps) figures; The beam spin asymmetries in the hard exclusive electroproduction of photons on the proton (ep -> epg) were measured over a wide kinematic range and with high statistical accuracy. These asymmetries result from the interference of the Bethe-Heitler process and of deeply virtual Compton scattering. Over the whole kinematic range (x_B from 0.11 to 0.58, Q^2 from 1 to 4.8 GeV^2, -t from 0.09 to 1.8 GeV^2), the azimuthal dependence of the asymmetries is compatible with expectations from leading-twist dominance, A = a*sin(phi)/[1+c*cos(phi)]. This extensive set of data can thus be used to constrain significantly the generalized parton distributions of the nucleon in the valence quark sector.
Published: 2008

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Publication Type

Journal

Database

Publisher

169 results on '"J. M. Laget"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources