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65 results on '"Adhikari, K"'

1. First measurement of direct photoproduction of the a2(1320)0 meson on the proton

Author

Celentano, A., Battaglieri, M., De Vita, R., Marsicano, L., Mathieu, V., Pilloni, A., Szczepaniak, A., Adhikari, K. P., Adhikari, S., Amaryan, M. J., Angelini, G., Atac, H., Barion, L., Bedlinskiy, I., Benmokhtar, Fatiha, Bianconi, A., Biselli, A. S., Bossù, F., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Bulumulla, D., Burkert, V. D., Carman, D. S., Carvajal, J. C., Chatagnon, P., Chetry, T., Ciullo, G., Clark, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., Cruz-Torres, R., D'Angelo, A., Dashyan, N., Defurne, M., Deur, A., Diehl, S., Djalali, C., Dugger, M., Dupre, R., Egiyan, H., Ehrhart, M., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fedotov, G., Fersch, R., Filippi, A., Gavalian, G., Gevorgyan, N., Girod, F. X., Glazier, D. I., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Hafidi, K., Hakobyan, H., Harrison, N., Hattawy, M., Hauenstein, F., Hayward, T. B., Heddle, D., Hicks, K., Hobart, A., Holtrop, M., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jo, H. S., Joo, K., Joosten, S., Keller, D., Khachatryan, M., Khanal, A., Khandaker, M., Kim, A., Kim, C. W., Kim, W., Klein, F. J., Kubarovsky, V., Lanza, L., Leali, M., Lenisa, P., Livingston, K., Lucherini, V., MacGregor, I. J. D., Marchand, D., Markov, N., Mascagna, V., McCracken, M. E., McKinnon, B., Meziani, Z.-E., Mirazita, M., Mokeev, V., Movsisyan, A., Munevar, E., Munoz Camacho, C., Nadel-Turonski, P., Neupane, K., Niccolai, S., Niculescu, G., Osipenko, M., Ostrovidov, A. I., Paolone, M., Pappalardo, L. L., Paremuzyan, R., Pasyuk, E., Phelps, W., Pogorelko, O., Price, J. W., Prok, Y., Ripani, M., Ritman, J., Rizzo, A., Rosner, G., Rowley, J., Sabatié, F., Salgado, C., Schmidt, A., Schumacher, R. A., Shrestha, U., Sokan, D., Soto, O., Sparveris, N., Stepanyan, S., Strakovsky, I. I., Strauch, S., Tan, J. A., Tyler, N., Ungaro, M., Venturelli, L., Voskanyan, H., Voutier, E., Watts, D., Wei, X., Wood, M. H., Zachariou, N., Zhang, J., Zhao, Z. W., Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and CLAS

Subjects
Nuclear Theory, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Hadronic Physics and QCD, Socio-culturale, FOS: Physical sciences, Regge, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], beam: energy, High Energy Physics - Experiment, Nuclear Theory (nucl-th), differential cross section: measured, High Energy Physics - Experiment (hep-ex), PE2_2, PE2_1, CLAS, mass spectrum: (pi0 eta), [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], angular distribution, photon p: exclusive reaction, Nuclear Experiment (nucl-ex), Nuclear Experiment, PE2_3, Nucleons, Mesons, Settore FIS/04, photon p: inelastic scattering, partial wave analysis, photon: energy, Photoproduction, meson: photoproduction, experimental results
Abstract

We present the first measurement of the exclusive reaction $\gamma p \rightarrow a_2(1320)^0 \, p$ in the photon energy range $3.5$-$5.5$ GeV and four-momentum transfer squared $0.2, Comment: Version accepted for publication in PRC, "Rapid Communications" section

Published
2020

2. Beam-target helicity asymmetry E in K0Λ and K0Σ0 photoproduction on the neutron

Author

Ho, D. H., Schumacher, R. A., D'Angelo, A., Deur, A., Fleming, J., Hanretty, C., Kageya, T., Klein, F. J., Klempt, E., Lowry, M. M., Lu, H., Nikonov, V. A., Peng, P., Sandorfi, A. M., Sarantsev, A. V., Strakovsky, I. I., Walford, N. K., Wei, X., Workman, R. L., Adhikari, K. P., Adhikari, S., Adikaram, D., Akbar, Z., Ball, J., Barion, L., Bashkanov, M., Bass, C. D., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Briscoe, W. J., Boiarinov, S., Burkert, V. D., Cao, F., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Chatagnon, P., Chetry, T., Ciullo, G., Clary, B. A., Cole, P., Collins, P., Contalbrigo, M., Crede, V., De Vita, R., Defurne, M., Diehl, S., Djalali, C., Dupre, R., Egiyan, H., Ehrhart, M., El Alaoui, A., El Fassi, L., Eugenio, P., Fedotov, G., Fegan, S., Fersch, R., Filippi, A., Fradi, A., Ghandilyan, Y., Giovanetti, K. L., Girod, F. X., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Hafidi, K., Hakobyan, H., Harrison, N., Hattawy, M., Heddle, D., Hicks, K., Holtrop, M., Ilieva, Y., Ireland, D.G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jo, H. S., Johnston, S., Kabir, M. L., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Kim, A., Kim, W., Klein, A., Kubarovsky, V., Laine, V., Lanza, L., Lenisa, P., Livingston, K., MacGregor, I.J.D., Marchand, D., Markov, N., Mayer, M., McKinnon, B., Meyer, C. A., Mirazita, M., Mokeev, V., Montgomery, R.A., Movsisyan, A., Munoz Camacho, C., Nadel-Turonski, P., Niccolai, S., Niculescu, G., O'Connell, T., Osipenko, M., Ostrovidov, A. I., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Pogorelko, O., Price, J. W., Prok, Y., Protopopescu, D., Rehfuss, M., Ripani, M., Riser, D., Rizzo, A., Rosner, G., Sabatié, F., Salgado, C., Sharabian, Y. G., Skorodumina, Iu., Smith, G. D., Sober, D. I., Sokhan, D., Sparveris, N., Strauch, S., Taiuti, M., Tan, J. A., Ungaro, M., Voskanyan, H., Voutier, E., Wang, R., Watts, D. P., Weinstein, L. B., Whisnant, C. S., Wood, M. H., Zachariou, N., Zhang, J., Zhao, Z. W., and Zonta, I.

Subjects
Nuclear and High Energy Physics, Nuclear Theory, Socio-culturale, Nuclear Experiment, Settore FIS/04 - Fisica Nucleare e Subnucleare
Abstract

We report the first measurements of the E beam-target helicity asymmetry for the →γ→n→K0Λ and K0Σ0 channels in the energy range 1.70≤W≤2.34 GeV. The CLAS system at Jefferson Lab uses a circularly polarized photon beam and a target consisting of longitudinally polarized solid molecular hydrogen deuteride with low background contamination for the measurements. The multivariate analysis method boosted decision trees is used to isolate the reactions of interest. Comparisons with predictions from the KaonMAID, SAID, and Bonn-Gatchina models are presented. These results will help separate the isospin I=0 and I=1 photocoupling transition amplitudes in pseudoscalar meson photoproduction.

Published
2018

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

Author

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

Subjects
Nuclear and High Energy Physics, Nuclear Theory, Socio-culturale, High Energy Physics::Experiment, Nuclear Experiment, Settore FIS/04 - Fisica Nucleare e Subnucleare
Abstract

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

Published
2018

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

Author

Kunkel, M. C., Amaryan, M. J., Strakovsky, I. I., Ritman, J., Goldstein, G. R., Adhikari, K. P., Adhikari, S., Avakian, H., Ball, J., Balossino, I., Barion, L., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Bultmann, S., Burkert, V. D., Cao, F., Carman, D. S., Celentano, A., Charles, G., Chetry, T., Ciullo, G., Clark, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Degtyarenko, P. V., Defurne, M., Deur, A., Djalali, C., Dugger, M., Dupre, R., Egiyan, H., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fedotov, G., Fersch, R., Filippi, A., Fradi, A., Gavalian, G., Ghandilyan, Y., Ghosh, S., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Glazier, D. I., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guo, L., Guidal, M., Hafidi, K., Hakobyan, H., Harrison, N., Hattawy, M., Hicks, K., Holtrop, M., Hyde, C. E., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Joo, K., Kabir, M. L., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F., Kubarovsky, V., Kuhn, S. E., Laget, J. M., Lanza, L., Lenisa, P., Lersch, D., Livingston, K., Macgregor, I. J. D., Markov, N., Mbianda Njencheu, G., Mckinnon, B., Mineeva, T., Mokeev, V., Montgomery, R. A., Movsisyan, A., Munoz Camacho, C., Nadel-Turonski, P., Niccolai, S., Niculescu, G., Osipenko, M., Ostrovidov, A. I., Paolone, M., Park, K., Pasyuk, E., Payette, D., Phelps, W., Pogorelko, O., Poudel, J., Price, J. W., Procureur, S., Prok, Y., Protopopescu, D., Ripani, M., Ritchie, B. G., Rizzo, A., Rosner, G., Roy, A., Sabatie, F., Salgado, C., Schadmand, S., Schumacher, R. A., Sharabian, Y. G., Skorodumina, I., Stepanyan, S., Sokhan, D., Sober, D. I., Sparveris, N., Strauch, S., Taiuti, M., Tan, J. A., Ungaro, M., Voskanyan, H., Voutier, E., Watts, D. P., Weinstein, L., Wei, X., Weygand, D. P., Zachariou, N., Zhang, J., and Zhao, Z. W.

Published
2018

5. Measurement of the helicity asymmetry E in ω → π+π−π0 photoproduction

Author

Akbar, Z., Roy, P., Park, S., Crede, V., Anisovich, A. V., Denisenko, I., Klempt, E., Nikonov, V. A., Sarantsev, A. V., Adhikari, K. P., Adhikari, S., Amaryan, M. J., Anefalos Pereira, S., Avakian, H., Ball, J., Battaglieri, M., Batourine, V., Bedlinskiy, I., Boiarinov, S., Briscoe, W. J., Brock, J., Brooks, W. K., Burkert, V. D., Cao, F. T., Carlin, C., Carman, D. S., Celentano, A., Charles, G., Chetry, T., Ciullo, G., Clark, L., Cole, P. L., Contalbrigo, M., Cortes, O., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Dugger, M., Dupre, R., Egiyan, H., El Fassi, L., Eugenio, P., Fedotov, G., Fersch, R., Filippi, A., Fradi, A., Garcon, M., Gevorgyan, N., Giovanetti, K. L., Girod, F. X., Gleason, C., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Heddle, D., Hicks, K., Hollis, G., Holtrop, M., Ireland, D.G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Joosten, S., Keith, C. D., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Lanza, L., Livingston, K., MacGregor, I.J.D., Markov, N., McKinnon, B., Meekins, D. G., Mineeva, T., Mokeev, V., Movsisyan, A., Munoz Camacho, C., Nadel-Turonski, P., Niccolai, S., Osipenko, M., Ostrovidov, A. I., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Phelps, W., Pogorelko, O., Price, J. W., Prok, Y., Protopopescu, D., Raue, B. A., Ripani, M., Ritchie, B. G., Rizzo, A., Rosner, G., Sabatié, F., Salgado, C., Schumacher, R. A., Sharabian, Y. G., Skorodumina, Iu., Smith, G. D., Sober, D. I., Sokhan, D., Sparveris, N., Stepanyan, S., Strakovsky, I. I., Strauch, S., Taiuti, M., Ungaro, M., Voskanyan, H., Voutier, E., Wei, X., Wood, M. H., Zachariou, N., Zana, L., Zhang, J., and Zhao, Z. W.

Subjects
Nuclear Experiment
Abstract

The double-polarization observable E was studied for the reaction γp → pω using the CEBAF Large\ud Acceptance Spectrometer (CLAS) in Hall B at the Thomas Jefferson National Accelerator Facility and the\ud longitudinally polarized frozen-spin target (FROST). The observable was measured from the charged decay\ud mode of the meson, ω → π+π−π0, using a circularly polarized tagged-photon beam with energies ranging\ud from the ω threshold at 1.1 to 2.3 GeV. A partial-wave analysis within the Bonn-Gatchina framework found\ud dominant contributions from the 3/2+ partial wave near threshold, which is identified with the subthreshold\ud N(1720) 3/2+ nucleon resonance. To describe the entire data set, which consisted of ω differential cross sections\ud and a large variety of polarization observables, further contributions from other nucleon resonances were found\ud to be necessary. With respect to nonresonant mechanisms, π exchange in the t channel was found to remain small\ud across the analyzed energy range, while Pomeron t-channel exchange gradually grew from the reaction threshold\ud to dominate all other contributions above W ≈ 2 GeV.

Published
2017

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

Author

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

Subjects
High Energy Physics::Experiment, Nuclear Experiment
Abstract

We present the results of our final analysis of the full data set of \ud g\ud p\ud 1\ud (\ud Q\ud 2\ud )\ud , the spin structure function of the proton, collected using CLAS at Jefferson Laboratory in 2000–2001. Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.7 GeV were scattered from proton targets (\ud 15\ud NH\ud 3\ud dynamically polarized along the beam direction) and detected with CLAS. From the measured double spin asymmetries, we extracted virtual photon asymmetries \ud A\ud p\ud 1\ud and \ud A\ud p\ud 2\ud and spin structure functions \ud g\ud p\ud 1\ud and \ud g\ud p\ud 2\ud over a wide kinematic range (0.05 \ud GeV\ud 2\ud

Published
2017

7. Differential cross section measurements for γn → π−p above the first nucleon resonance region

Author

Mattione, P. T., Carman, D. S., Strakovsky, I. I., Workman, R. L., Kudryavtsev, A. E., Svarc, A., Tarasov, V. E., Adhikari, K. P., Adhikari, S., Adikaram, D., Akbar, Z., Anefalos Pereira, S., Ball, J., Baltzell, N. A., Bashkanov, M., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Burkert, V. D., Cao, T., Celentano, A., Charles, G., Chetry, T., Ciullo, G., Clark, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Defurne, M., Deur, A., Djalali, C., Dugger, M., Dupre, R., Egiyan, H., El Alaoui, A., El Fassi, L., Eugenio, P., Fedotov, G., Fersch, R., Filippi, A., Fleming, J. A., Fradi, A., Ghandilyan, Y., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Gleason, C., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Heddle, D., Hicks, K., Hollis, G., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D.G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jiang, H., Jo, H. S., Joo, K., Joosten, S., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Kuleshov, S. V., Lanza, L., Lenisa, P., Livingston, K., MacGregor, I. J. D., Markov, N., McKinnon, B., Meyer, C. A., Meziani, Z. E., Mineeva, T., Mokeev, V., Montgomery, R. A., Movsisyan, A., Munoz Camacho, C., Murdoch, G., Nadel-Turonski, P., Net, L. A., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Phelps, W., Pisano, S., Pogorelko, O., Price, J. W., Procureur, S., Prok, Y., Protopopescu, D., Raue, B. A., Ripani, M., Ritchie, B. G., Rizzo, A., Rosner, G., Sabatié, F., Salgado, C., Schumacher, R. A., Sharabian, Y. G., Simonyan, A., Skorodumina, Iu., Smith, G. D., Sokhan, D., Sparveris, N., Stankovic, I., Stepanyan, S., Strauch, S., Taiuti, M., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D., Wei, X., Wood, M. H., Zachariou, N., Zhang, J., and Zhao, Z. W.

Subjects
High Energy Physics::Experiment
Abstract

The quasifree \ud γ\ud d\ud →\ud π\ud −\ud p\ud (\ud p\ud )\ud differential cross section has been measured with CLAS at photon beam energies \ud E\ud γ\ud from 0.445 to 2.510 GeV (corresponding to \ud W\ud from 1.311 to 2.366 GeV) for pion center-of-mass angles \ud cos\ud θ\ud c\ud .\ud m\ud .\ud π\ud from \ud −\ud 0.72\ud to 0.92. A correction for final state interactions has been applied to these data to extract the \ud γ\ud n\ud →\ud π\ud −\ud p\ud differential cross sections. These cross sections are quoted in 8428 \ud (\ud E\ud γ\ud ,\ud cos\ud θ\ud c\ud .\ud m\ud .\ud π\ud )\ud bins, a factor of nearly 3 increase in the world statistics for this channel in this kinematic range. These new data help to constrain coupled-channel analysis fits used to disentangle the spectrum of \ud N\ud ∗\ud resonances and extract their properties. Selected photon decay amplitudes \ud N\ud ∗\ud →\ud γ\ud n\ud at the resonance poles are determined for the first time and are reported here.

Published
2017

8. Measurements of ep→e′π+π−p′ cross sections with CLAS at 1.40 GeV < W < 2.0 GeV and 2.0 GeV2 < Q2 < 5.0 GeV2

Author

Isupov, E. L., Burkert, V. D., Carman, D. S., Gothe, R. W., Hicks, K., Ishkhanov, B. S., Mokeev, V. I., Adhikari, K. P., Adhikari, S., Adikaram, D., Akbar, Z., Amaryan, M. J., Anefalos Pereira, S., Avakian, H., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Briscoe, W. J., Brooks, W. K., Bültmann, S., Cao, T., Celentano, A., Charles, G., Chetry, T., Ciullo, G., Clark, L., Colaneri, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Dupre, R., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fedotov, G., Fersch, R., Filippi, A., Fleming, J. A., Forest, T. A., Garçon, M., Gavalian, G., Ghandilyan, Y., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Glazier, D. I., Gleason, C., Golovatch, E., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Heddle, D., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D. G., Jenkins, D., Jiang, H., Joo, K., Joosten, S., Keller, D., Khachatryan, G., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Kuleshov, S. V., Kunkel, M., Lanza, L., Lenisa, P., Livingston, K., Lu, H. Y., MacGregor, I. J. D., Markov, N., McKinnon, B., Mineeva, T., Mirazita, M., Montgomery, R. A., Movsisyan, A., Munevar, E., Munoz Camacho, C., Murdoch, G., Nadel-Turonski, P., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Phelps, W., Pogorelko, O., Price, J. W., Procureur, S., Prok, Y., Protopopescu, D., Raue, B. A., Ripani, M., Riser, D., Ritchie, B. G., Rizzo, A., Sabatié, F., Salgado, C., Schumacher, R. A., Sharabian, Y. G., Simonyan, A., Skorodumina, Iu., Smith, G. D., Sokhan, D., Sparveris, N., Stankovic, I., Strakovsky, I. I., Strauch, S., Taiuti, M., Tian, Ye, Torayev, B., Trivedi, A., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Wei, X., Wood, M. H., Zachariou, N., and Zhang, J.

Abstract

This paper reports new exclusive cross sections for ep → ep\ud π+π−p' using the CLAS detector at Jefferson\ud Laboratory. These results are presented for the first time at photon virtualities 2.0 GeV2 < Q2 < 5.0 GeV2 in\ud the center-of-mass energy range 1.4 GeV

Published
2017

9. Target and beam-target spin asymmetries in exclusive pion electroproduction for Q2>1 GeV2. II. ep→eπ0p

Author

Bosted, P. E., Kim, A., Adhikari, K. P., Adikaram, D., Akbar, Z., Amaryan, M. J., Anefalos Pereira, S., Avakian, H., Badui, R. A., Ball, J., Balossino, I., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Bültmann, S., Burkert, V. D., Cao, T., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Chetry, T., Ciullo, G., Clark, L., Colaneri, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Dupre, R., Egiyan, H., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fanchini, E., Fedotov, G., Fegan, S., Fersch, R., Filippi, A., Fleming, J. A., Forest, T. A., Fradi, A., Ghandilyan, Y., Gilfoyle, G. P., Girod, F. X., Glazier, D. I., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guler, N., Hakobyan, H., Guo, L., Hafidi, K., Hanretty, C., Harrison, N., Hattawy, M., Heddle, D., Hicks, K., Hollis, G., Holtrop, M., Hughes, S. M., Ireland, D. G., Isupov, E. L., Jenkins, D., Jiang, H., Jo, H. S., Joo, K., Keller, D., Khachatryan, G., Khandaker, M., Kim, W., Klei, A., Klein, F. J., Koirala, S., Kubarovsky, V., Kuhn, S. E., Lanza, L., Lenisa, P., Livingston, K., Lu, H. Y., MacGregor, I. J. D., Markov, N., Mayer, M., McCracken, M. E., McKinnon, B., Mineeva, T., Mirazita, M., Mokeev, V. I., Montgomery, R. A., Movsisyan, A., Munoz Camacho, C., Murdoch, G., Nadel-Turonski, P., Ni, A., Niccolai, S., Niculescu, G., Osipenko, M., Ostrovidov, A. I., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Phelps, W., Pisano, S., Pogorelko, O., Price, J. W., Prok, Y., Protopopescu, D., Puckett, A. J. R., Raue, B. A., Ripani, M., Rizzo, A., Rosner, G., Rossi, P., Roy, P., Sabatié, F., Saini, M. S., Schumacher, R. A., Seder, E., Sharabian, Y. G., Skorodumina, Iu., Smith, G. D., Sokhan, D., Sparveris, N., Stankovic, I., Stepanyan, S., Stoler, P., Strakovsky, I. I., Strauch, S., Taiuti, M., Tian, Ye, Torayev, B., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D. P., Wei, X., Weinstein, L. B., Zachariou, N., Zhang, J., Zhao, Z. W., and Zonta, I.

Subjects
Nuclear and High Energy Physics, Economica, Socio-culturale, High Energy Physics::Experiment, RESONANCE, Nuclear Experiment, Settore FIS/04 - Fisica Nucleare e Subnucleare
Abstract

Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive \ud π\ud 0\ud electroproduction reaction \ud γ\ud ∗\ud p\ud →\ud p\ud π\ud 0\ud , expanding an analysis of the \ud γ\ud ∗\ud p\ud →\ud n\ud π\ud +\ud reaction from the same experiment. The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic ranges covered are \ud 1.1\ud

Published
2017

10. Target and beam-target spin asymmetries in exclusive π+ and π- Electroproduction with 1.6- to 5.7-GeV electrons

Author

Bosted, P, Biselli, A, Careccia, S, Dodge, G, Fersch, R, Guler, N, Kuhn, S, Pierce, J, Prok, Y, Zheng, X, Adhikari, K, Adikaram, D, Akbar, Z, Amaryan, M, Anefalos Pereira, S, Asryan, G, Avakian, H, Badui, R, Ball, J, Baltzell, N, Battaglieri, M, Batourine, V, Bedlinskiy, I, Boiarinov, S, Briscoe, W, Bultmann, S, Burkert, V, Cao, T, Carman, D, Celentano, A, Chandavar, S, Charles, G, Chetry, T, Ciullo, G, Clark, L, Colaneri, L, Cole, P, Contalbrigo, M, Cortes, O, Crede, V, D'Angelo, A, Dashyan, N, De Vita, R, Deur, A, Djalali, C, Dupre, R, Egiyan, H, El Alaoui, A, El Fassi, L, Eugenio, P, Fanchini, E, Fedotov, G, Filippi, A, Fleming, J, Forest, T, Fradi, A, Garcon, M, Gevorgyan, N, Ghandilyan, Y, Gilfoyle, G, Giovanetti, K, Girod, F, Gleason, C, Gohn, W, Golovatch, E, Gothe, R, Griffioen, K, Guo, L, Hafidi, K, Hanretty, C, Harrison, N, Hattawy, M, Heddle, D, Hicks, K, Holtrop, M, Hughes, S, Ilieva, Y, Ireland, D, Ishkhanov, B, Isupov, E, Jenkins, D, Jiang, H, Hs, J, Joo, K, Joosten, S, Keller, D, Khandaker, M, Kim, W, Klein, A, Klein, Kubarovsky, F, V, Kuleshov, S, Lanza, L, Lenisa, P, Livingston, K, Hy, L, Macgregor, I, Markov, N, Mccracken, M, Mckinnon, B, Meyer, C, Minehart, R, Mirazita, M, Mokeev, V, Movsisyan, A, Munevar, E, Munoz Camacho, C, Nadel Turonski, P, Net, L, Ni, A, Niccolai, S, Niculescu, G, Niculescu, I, Osipenko, M, Ostrovidov, A, Paremuzyan, R, Park, K, Pasyuk, E, Peng, P, Phelps, W, Pisano, S, Pogorelko, O, Price, J, Procureur, S, Protopopescu, D, Puckett, A, Raue, B, Ripani, M, Rizzo, A, Rosner, G, Rossi, P, Roy, P, Sabatie, F, Salgado, C, Schumacher, R, Seder, E, Sharabian, Y, Simonyan, A, Skorodumina, I, Smith, G, Sparveris, N, Stankovic, I, Stepanyan, S, Strakovsky, I, Strauch, S, Sytnik, V, Taiuti, M, Tian, Y, Torayev, B, Ungaro, M, Voskanyan, H, Voutier, E, Walford, N, Watts, D, Wei, X, Weinstein, L, Wood, M, Zachariou, N, Zana, L, Zhang, J, Zhao, Z, and Zonta, I

Subjects
GEV2, DEUTERONS, CLAS, CHARGED PIONS, NUCLEON, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2016

11. Measurement of target and double-spin asymmetries for the e p → eπ+(n) reaction in the nucleon resonance region at low Q2

Author

Zheng, X., Adhikari, K. P., Bosted, P., Deur, A., Drozdov, V., El Fassi, L., Kang, Hyekoo, Kovacs, K., Kuhn, S., Long, E., Phillips, S. K., Ripani, M., Slifer, K., Smith, L. C., Adikaram, D., Akbar, Z., Amaryan, M. J., Anefalos Pereira, S., Asryan, G., Avakian, H., Badui, R. A., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Briscoe, W. J., Bültmann, S., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Chen, J.-P., Chetry, T., Choi, Seonho, Ciullo, G., Clark, L., Colaneri, L., Cole, P. L., Compton, N., Contalbrigo, M., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Djalali, C., Dodge, G. E., Dupre, R., Egiyan, H., El Alaoui, A., Elouadrhiri, L., Eugenio, P., Fanchini, E., Fedotov, G., Fersch, R., Filippi, A., Fleming, J. A., Gevorgyan, N., Ghandilyan, Y., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Gleason, C., Golovach, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guler, N., Guo, L., Hanretty, C., Harrison, N., Hattawy, M., Hicks, K., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D.G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jiang, H., Jo, H. S., Joosten, S., Keller, D., Khachatryan, G., Khandaker, M., Kim, A., Kim, W., Klein, F. J., Kubarovsky, V., Lanza, L., Lenisa, P., Livingston, K., MacGregor, I.J.D., Markov, N., McKinnon, B., Mirazita, M., Mokeev, V., Movsisyan, A., Munevar, E., Munoz Camacho, C., Murdoch, G., Nadel-Turonski, P., Net, L. A., Ni, A., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Peng, P., Pisano, S., Pogorelko, O., Price, J. W., Puckett, A. J. R., Raue, B. A., Rizzo, A., Rosner, G., Rossi, P., Roy, P., Sabatié, F., Salgado, C., Schumacher, R. A., Sharabian, Y. G., Skorodumina, Iu., Smith, G. D., Sokhan, D., Sparveris, N., Stankovic, I., Strakovsky, I. I., Strauch, S., Taiuti, M., Tian, Ye, Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D. P., Wei, X., Weinstein, L. B., Wood, M. H., Zachariou, N., Zhang, J., and Zonta, I.

Subjects
Nuclear and High Energy Physics, Economica, Socio-culturale, High Energy Physics::Experiment, Nuclear Experiment, Settore FIS/04 - Fisica Nucleare e Subnucleare
Abstract

We report measurements of target- and double-spin asymmetries for the exclusive channel ep → eπ+(n) in\ud the nucleon resonance region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). These\ud asymmetries were extracted from data obtained using a longitudinally polarized NH3 target and a longitudinally\ud polarized electron beam with energies 1.1, 1.3, 2.0, 2.3, and 3.0 GeV. The new results are consistent with previous\ud CLAS publications but are extended to a low Q2 range from 0.0065 to 0.35 (GeV/c)\ud 2. The Q2 access was made\ud possible by a custom-built Cherenkov detector that allowed the detection of electrons for scattering angles as low\ud as 6◦. These results are compared with the unitary isobar models JANR and MAID, the partial-wave analysis\ud prediction from SAID, and the dynamic model DMT. In many kinematic regions our results, in particular results\ud on the target asymmetry, help to constrain the polarization-dependent components of these models.

Published
2016

12. Photoproduction of Λ and Σ0 hyperons using linearly polarized photons

Author

Paterson, C, Ireland, D, Livingston, K, Mckinnon, B, Adhikari, K, Adikaram, D, Akbar, Z, Amaryan, M, Anefalos Pereira, S, Badui, R, Ball, J, Baltzell, N, Battaglieri, M, Bedlinskiy, I, Biselli, A, Briscoe, W, Brooks, W, Burkert, V, Carman, D, Celentano, A, Chetry, T, Ciullo, G, Clark, L, Colaneri, L, Cole, P, Compton, N, Contalbrigo, M, Cortes, O, Crede, V, D'Angelo, A, De Vita, R, Deur, A, Djalali, C, Dugger, M, Dupre, R, Egiyan, H, El Alaoui, A, El Fassi, L, Fanchini, E, Fedotov, G, Filippi, A, Fleming, J, Gevorgyan, N, Ghandilyan, Y, Gilfoyle, G, Giovanetti, K, Girod, F, Glazier, D, Gleason, C, Gothe, R, Griffioen, K, Guo, L, Hafidi, K, Harrison, N, Hattawy, M, Hicks, K, Holtrop, M, Hughes, S, Ilieva, Y, Ishkhanov, B, Isupov, E, Jenkins, D, Jiang, H, Joo, K, Keller, D, Khachatryan, G, Khandaker, M, Kim, W, Klein, F, Kubarovsky, V, Kuleshov, S, Lanza, L, Lenisa, P, Hy, L, Macgregor, I, Markov, N, Mattione, P, Mayer, C, Mccracken, M, Mokeev, V, Movsisyan, A, Munevar, E, Munoz Camacho, C, Nadel Turonski, P, Net, L, Ni, A, Niccolai, S, Niculescu, G, Osipenko, M, Ostrovidov, A, Paremuzyan, R, Park, K, Pasyuk, E, Peng, P, Pisano, S, Pogorelko, O, Price, J, Prok, Y, Protopopescu, D, Puckett, A, Raue, B, Ripani, M, Ritchie, B, Rizzo, A, Rosner, G, Roy, P, Sabatie, F, Salgado, C, Schumacher, R, Seder, E, Sharabian, Y, Skorodumina, I, Smith, G, Sober, D, Sokhan, D, Sparveris, N, Strakovsky, I, Strauch, S, Sytnik, V, Taiuti, M, Torayev, B, Tucker, R, Ungaro, M, Voskanyan, H, Voutier, E, Walford, N, Watts, D, Wei, X, Zachariou, N, Zana, L, Zhang, J, and Zonta, I

Subjects
BREMSSTRAHLUNG, BEAM, OBSERVABLES, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2016

13. Strangeness Suppression of q(q)over-bar Creation Observed in Exclusive Reactions

Author

Mestayer, M, Park, K, Adhikari, K, Aghasyan, M, Pereira, S, Ball, J, Battaglieri, M, Batourine, V, Bedlinskiy, I, Biselli, A, Boiarinov, S, Briscoe, W, Brooks, W, Burkert, V, Carman, D, Celentano, A, Chandavar, S, Charles, G, Colaneri, L, Cole, P, Contalbrigo, M, Cortes, O, Crede, V, D'Angelo, A, Dashyan, N, De Vita, R, Deur, A, Djalali, C, Doughty, D, Dupre, R, El Alaoui, A, El Fassi, L, Elouadrhiri, L, Eugenio, P, Fedotov, G, Fleming, J, Forest, T, Garillon, B, Garcn, M, Ghandilyan, Y, Gilfoyle, G, Giovanetti, K, Girod, F, Goetz, J, Golovatch, E, Gothe, R, Griffioen, K, Guegan, B, Guidal, M, Hakobyan, H, Hanretty, C, Hattawy, M, Holtrop, M, Hughes, S, Hyde, C, Ilieva, Y, Ireland, D, Jiang, H, Jo, H, Joo, K, Keller, D, Khandaker, M, Kim, A, Kim, W, Koirala, S, Kubarovsky, V, Kuleshov, S, Lenisa, P, Levine, W, Livingston, K, Lu, H, Macgregor, I, Mayer, M, Mckinnon, B, Meyer, C, Mirazita, M, Mokeev, V, Montgomery, R, Moody, C, Moutarde, H, Movsisyan, A, Camacho, C, Nadel Turonski, P, Niccolai, S, Niculescu, G, Niculescu, I, Osipenko, M, Ostrovidov, A, Pappalardo, L, Paremuzyan, R, Peng, P, Phelps, W, Pisano, S, Pogorelko, O, Pozdniakov, S, Price, J, Protopopescu, D, Puckett, A, Raue, B, Rimal, D, Ripani, M, Rizzo, A, Rosner, G, Roy, P, Sabatie, F, Saini, M, Schott, D, Schumacher, R, Simonyan, A, Sokhan, D, Strauch, S, Sytnik, V, Tang, W, Tian, Y, Ungaro, M, Vernarsky, B, Vlassov, A, Voskanyan, H, Voutier, E, Walford, N, Watts, D, Wei, X, Weinstein, L, Wood, M, Zachariou, N, Zhang, J, Zhao, Z, and Zonta, I

Subjects
FLUX-TUBE MODEL, PARTICLE-PRODUCTION, QUARK SUPPRESSION, FLAVOR ASYMMETRY, E&E ANNIHILATION, HIGH-ENERGY, SCATTERING, VERTICES, SEA, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2014

14. Exclusive pi(0) electroproduction at W > 2 GeV with CLAS

Author

Bedlinskiy, I, Kubarovsky, V, Niccolai, S, Stoler, P, Adhikari, K, Anderson, M, Pereira, S, Avakian, H, Ball, J, Baltzell, N, Battaglieri, M, Batourine, V, Biselli, A, Boiarinov, S, Bono, J, Briscoe, W, Brooks, W, Burkert, V, Carman, D, Celentano, A, Chandavar, S, Colaneri, L, Cole, P, Contalbrigo, M, Cortes, O, Crede, V, D'Angelo, A, Dashyan, N, De Vita, R, De Sanctis, E, Deur, A, Djalali, C, Doughty, D, Dupre, R, Egiyan, H, El Alaoui, A, El Fassi, L, Elouadrhiri, L, Eugenio, P, Fedotov, G, Fegan, S, Fleming, J, Forest, T, Garillon, B, Garcon, M, Gavalian, G, Gevorgyan, N, Ghandilyan, Y, Gilfoyle, G, Giovanetti, K, Girod, F, Golovatch, E, Gothe, R, Griffioen, K, Guegan, B, Guidal, M, Guo, L, Hafidi, K, Hakobyan, H, Harrison, N, Hattawy, M, Hicks, K, Holtrop, M, Ireland, D, Ishkhanov, B, Isupov, E, Jenkins, D, Jo, H, Joo, K, Keller, D, Khandaker, M, Kim, A, Kim, W, Klein, A, Klein, F, Koirala, S, Kuhn, S, Kuleshov, S, Lenisa, P, Levine, W, Livingston, K, Lu, H, Macgregor, I, Markov, N, Mayer, M, Mckinnon, B, Mirazita, M, Mokeev, V, Montgomery, R, Moody, C, Moutarde, H, Movsisyan, A, Camacho, C, Nadel Turonski, P, Niculescu, I, Osipenko, M, Ostrovidov, A, Pappalardo, L, Park, K, Park, S, Pasyuk, E, Phelps, E, Phelps, W, Phillips, J, Pisano, S, Pogorelko, O, Price, J, Prok, Y, Protopopescu, D, Procureur, S, Puckett, A, Raue, B, Ripani, M, Ritchie, B, Rizzo, A, Rossi, P, Roy, P, Sabatie, F, Salgado, C, Schott, D, Schumacher, R, Seder, E, Senderovich, I, Sharabian, Y, Simonyan, A, Smith, G, Sober, D, Sokhan, D, Stepanyan, S, Strauch, S, Sytnik, V, Tang, W, Tian, Y, Ungaro, M, Vlassov, A, Voskanyan, H, Voutier, E, Walford, N, Watts, D, Wei, X, Weinstein, L, Yurov, M, Zachariou, N, Zana, L, Zhang, J, Zhao, Z, and Zonta, I

Subjects
TRANSVERSITY, PARTON DISTRIBUTIONS, PION ELECTROPRODUCTION, MESONS, SYSTEM, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2014

15. Beam asymmetry Sigma for pi(+) and pi(0) photoproduction on the proton for photon energies from 1.102 to 1.862 GeV

Author

Dugger, M, Ritchie B, G, Collins, P, Pasyuk, E, Briscoe W, J, Strakovsky I, I, Workman R, L, Azimov, Y, Adhikari K, P, Adikaram, D, Aghasyan, M, Amaryan M, J, Anderson M, D, Pereira S, A, Avakian, H, Ball, J, Baltzell N, A, Battaglieri, M, Batourine, V, Bedlinskiy, I, Biselli A, S, Boiarinov, S, Burkert V, D, Carman D, S, Celentano, A, Chandavar, S, Cole P, L, Contalbrigo, M, Cortes, O, Crede, V, D'Angelo, A, Dashyan, N, De Vita, R, De Sanctis, E, Deur, A, Djalali, C, Doughty, D, Dupre, R, Egiyan, H, El Alaoui, A, El Fassi, L, Eugenio, P, Fedotov, G, Fegan, S, Fleming J, A, Gevorgyan, N, Gilfoyle G, P, Giovanetti K, L, Girod F, X, Goetz J, T, Gohn, W, Golovatch, E, Gothe R, W, Griffioen K, A, Guidal, M, Guo, L, Hafidi, K, Hakobyan, H, Hanretty, C, Harrison, N, Heddle, D, Hicks, K, Ho, D, Holtrop, M, Ilieva, Y, Ireland D, G, Ishkhanov B, S, Isupov E, L, Jo H, S, Joo, K, Keller, D, Khandaker, M, Kim, W, Klein, A, Klein F, J, Koirala, S, Kubarovsky, A, Kubarovsky, V, Kuleshov S, V, Lewis, S, Livingston, K, Lu H, Y, MacGregor I. J, D, Martinez, D, Mayer, M, Mckinnon, B, Mineeva, T, Mirazita, M, Mokeev, V, Montgomery R, A, Moutarde, H, Munevar, E, Camacho C, M, Nadel Turonski, P, Nepali C, S, Niccolai, S, Niculescu, G, Niculescu, I, Osipenko, M, Ostrovidov A, I, Pappalardo L, L, Paremuzyan, R, Park, K, Park, S, Phelps, E, Phillips J, J, Pisano, S, Pogorelko, O, Pozdniakov, S, Price J, W, Procureur, S, Prok, Y, Protopopescu, D, Raue B, A, Rimal, D, Ripani, M, Rosner, G, Rossi, P, Sabatie, F, Saini M, S, Salgado, C, Schott, D, Schumacher R, A, Seder, E, Seraydaryan, H, Sharabian Y, G, Smith G, D, Sober D, I, Sokhan, D, Stepanyan S, S, Stoler, P, Strauch, S, Null, T, Null, M, Tang, W, Tian, Y, Tkachenko, S, Torayev, B, Voskanyan, H, Voutier, E, Walford N, K, Watts D, P, Weygand D, P, Zachariou, N, L, Zhang, J, Zhao Z, W, and Zonta, I

Subjects
POSITIVE PION-PHOTOPRODUCTION, RESONANCE REGION, POLARIZED PHOTONS, CROSS-SECTION, PI-0 MESONS, CLAS, PARAMETERS, SYSTEM, PI0, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2013

16. Differential photoproduction cross sections of the Sigma(0)(1385), Lambda(1405), and Lambda(1520)

Author

Moriya, K, Schumacher R, A, Adhikari K, P, Adikaram, D, Aghasyan, M, Anderson, M, Pereira, S, Anefalos Ball, J, Baltzell N, A, Battaglieri, M, Batourine, V, Bedlinskiy, I, Bellis, M, Biselli A, S, Bono, J, Boiarinov, S, Briscoe W, J, Burkert V, D, Carman D, S, Celentano, A, Chandavar, S, Charles, G, Cole, P, Collins, P, Crede, V, D'Angelo, A, Dashyan, N, De Sanctis, E, De Vita, R, Deur, A, Dey, B, Djalali, C, Doughty, D, Dupre, R, Egiyan, H, El Fassi, L, Eugenio, P, Fedotov, G, Fegan, S, Fersch, R, Fleming J, A, Gevorgyan, N, Gilfoyle G, P, Giovanetti K, L, Girod, F, Null, X, Goetz J, T, Gohn, W, Golovatch, E, Gothe R, W, Griffioen K, A, Guidal, M, Hafidi, K, Hakobyan, H, Hanretty, C, Harrison, N, Heddle, D, Hicks, K, Ho, D, Holtrop, M, Hyde C, E, Ilieva, Y, Ireland D, G, Ishkhanov B, S, Isupov E, L, Jo, H, Null, S, Keller, D, Khandaker, M, Khetarpal, P, Kim, A, Kim, W, Klein, A, Klein, F, Null, J, Koirala, S, Kubarovsky, A, Kubarovsky, V, Kuleshov, S, Null, V, Kvaltine, N, Null, D, Livingston, K, Lu, H, Null, Y, Macgregor, I, Markov, N, Mayer, M, Mccracken, M, Mckinnon, B, Mestayer M, D, Meyer C, A, Mirazita, M, Mineeva, T, Mokeev, V, Montgomery R, A, Munevar, E, Camacho, C, Munoz Nadel Turonski, P, Nasseripour, R, Nepali C, S, Niccolai, S, Niculescu, G, Niculescu, I, Osipenko, M, Ostrovidov, A, Null, I, Pappalardo, L, Null, L, Paremuzyan, R, Park, K, Park, S, Pasyuk, E, Phelps, E, Phillips, J, Pisano, S, Pivnyuk, N, Pogorelko, O, Pozdniakov, S, Price, J, Null, W, Procureur, S, Protopopescu, D, Rimal, D, Ripani, M, Ritchie B, G, Rosner, G, Rossi, P, Sabatie, F, Saini M, S, Salgado, C, Schott, D, Seder, E, Seraydaryan, H, Sharabian Y, G, Smith E, S, Smith, G, Sober, D, Stepanyan S, S, Stepanyan, S, Stoler, P, Strakovsky I, I, Strauch, S, Taiuti, M, Tang, W, Taylor, S, Taylor C, E, Tian Ye Tkachenko, S, Torayev, B, Ungaro, M, Vernarsky, B, Vlassov A, V, Voskanyan, H, Voutier, E, Walford N, K, Watts D, P, Weygand D, P, Williams, M, Zachariou, N, Zana, L, Zhang, J, Zhao Z, W, and Zonta, I

Subjects
STATES, SCATTERING, HYPERON, MASSES, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2013

17. Cross sections for the γp→K*+Λ and γp→K*+Σ0 reactions measured at CLAS

Author

Tang, W., Hicks, K., Keller, D., Kim, S. H., Kim, H. C., Adhikari, K. P., Aghasyan, M., Amaryan, M. J., Anderson, M. D., Anefalos Pereira, S., Baltzell, N. A., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Bono, J., Boiarinov, S., Briscoe, W. J., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Cole, P. L., Collins, P., Contalbrigo, M., Cortes, O., Crede, V., D’Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Doughty, D., Dupre, R., Alaoui, A. El, Fassi, L. El, Eugenio, P., Fedotov, G., Fegan, S., Fleming, J. A., Gabrielyan, M. Y., Gevorgyan, N., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Heddle, D., Ho, D., Holtrop, M., Hyde, C. E., Ilieva, Y., Ireland, D.G., Ishkhanov, B. S., Isupov, E. L., Jo, H. S., Joo, K., Khandaker, M., Khetarpal, P., Kim, A., Kim, W., Klein, F. J., Koirala, S., Kubarovsky, A., Kubarovsky, V., Kuleshov, S. V., Livingston, K., Lu, H. Y., MacGregor, I.J.D., Mao, Y., Markov, N., Martinez, D., Mayer, M., McKinnon, B., Meyer, C. A., Mokeev, V., Moutarde, H., Munevar, E., Munoz Camacho, C., Nadel-Turonski, P., Nepali, C. S., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Pappalardo, L. L., Paremuzyan, R., Park, K., Park, S., Pasyuk, E., Phelps, E., Phillips, J. J., Pisano, S., Pogorelko, O., Pozdniakov, S., Price, J. W., Procureur, S., Prok, Y., Protopopescu, D., Puckett, A. J. R., Raue, B. A., Ripani, M., Rimal, D., Ritchie, B. G., Rosner, G., Rossi, P., Sabatié, F., Saini, M. S., Salgado, C., Schott, D., Schumacher, R. A., Seraydaryan, H., Sharabian, Y. G., Smith, G.D., Sober, D. I., Sokhan, Daria, Stepanyan, S. S., Stepanyan, S., Stoler, P., Strakovsky, I. I., Strauch, S., Taylor, C. E., Tian, Ye, Tkachenko, S., Torayev, B., Ungaro, M., Vernarsky, B., Vlassov, A. V., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D. P., Weinstein, L. B., Weygand, D. P., Wood, M. H., Zachariou, N., Zana, L., Zhang, J., Zhao, Z. W., and Zonta, I.

Subjects
SYSTEM, Settore FIS/04 - Fisica Nucleare e Subnucleare
Abstract

The first high-statistics cross sections for the reactions γp→K*+Λ and γp→K*+Σ0 were measured using the CLAS detector at photon energies between threshold and 3.9 GeV at the Thomas Jefferson National Accelerator Facility. Differential cross sections are presented over the full range of the center-of-mass angles, and then fitted to Legendre polynomials to extract the total cross section. Results for the K*+Λ final state are compared with two different calculations in an isobar and a Regge model, respectively. Theoretical calculations significantly underestimate the K*+Λ total cross sections between 2.1 and 2.6 GeV, but are in better agreement with present data at higher photon energies.

Published
2013

18. Comparison of forward and backward pp pair knockout in He-3(e,e'pp)n

Author

Baghdasaryan, H., Weinstein, L. B., Laget, J. M., Adhikari, K. P., Aghasyan, M., Amaryan, M. J., Anghinolfi, M., Ball, J., Battaglieri, M., Biselli, A. S., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Cole, P. L., Contalbrigo, M., Crede, V., D'Angelo, A., Daniel, A., Dashyan, N., De Sanctis, E., De Vita, R., Djalali, C., Dodge, G. E., Doughty, D., Dupre, R., Egiyan, H., El Alaoui, A., El Fassi, L., Elouadrhiri, L., Fedotov, G., Gabrielyan, M. Y., Gevorgyan, N., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Gohn, W., Gothe, R. W., Griffioen, K. A., Guegan, B., Guidal, M., Hafidi, K., Hicks, K., Hyde, C. E., Ireland, D. G., Ishkhanov, B. S., Jenkins, D., Jo, H. S., Joo, K., Khandaker, M., Khetarpal, P., Kim, A., Kim, W., Kubarovsky, A., Kubarovsky, V., Kuhn, S. E., Kuleshov, S. V., Kvaltine, N. D., Lu, H. Y., MacGregor, I. J. D., McKinnon, B., Mirazita, M., Mokeev, V., Moutarde, H., Munevar, E., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Paolone, M., Pappalardo, L. L., Paremuzyan, R., Park, K., Park, S., Pisano, S., Pozdniakov, S., Procureur, S., Raue, B. A., Ricco, G., Rimal, D., Ripani, M., Rosner, G., Rossi, P., Saini, M. S., Saylor, N. A., Schott, D., Schumacher, R. A., Seraydaryan, H., Smith, E. S., Sober, D. I., Sokan, D., Stepanyan, S. S., Stepanyan, S., Strauch, S., Taiuti, M., Tang, W., Tkachenko, S., Voskanyan, H., Voutier, E., Wood, M. H., Zana, L., and Zhao, B.

Subjects
MECHANISMS, DEUTERON, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2012

19. Measurement of the generalized form factors near threshold via gamma* p -> n pi(+) at high Q(2)

Author

Park, K., Gothe, R. W., Adhikari, K. P., Adikaram, D., Anghinolfi, M., Baghdasaryan, H., Ball, J., Battaglieri, M., Batourine, V., Bedlinskiy, I., Bennett, R. P., Biselli, A. S., Bookwalter, C., Boiarinov, S., Branford, D., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Cole, P. L., Contalbrigo, Marco, Crede, V., D'Angelo, A., Daniel, A., Dashyan, N., Vita, R. D., Sanctis, E. D., Deur, A., Djalali, C., Doughty, D., Dupre, R., Alaoui, A. E., Fassi, L. E., Eugenio, P., Fedotov, G., Fradi, A., Gabrielyan, M. Y., Gevorgyan, N., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Goetz, J. T., Gohn, W., Golovatch, E., Graham, L., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Heddle, D., Hicks, K., Holtrop, M., Hyde, C. E., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., H. S., Jo, Joo, K., Kalantarians, N., Khandaker, M., Khetarpal, P., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, A., Kubarovsky, V., Kuhn, S. E., Kuleshov, S. V., Kvaltine, N. D., Livingston, K., H. Y., Lu, I. J. D., Markov, N., Mayer, M., Mckinnon, B., Mestayer, M. D., Meyer, C. A., Mineeva, T., Mirazita, M., Mokeev, V., Moutarde, H., Munevar, E., Nadel Turonski, P., Nasseripour, R., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Paolone, M., Pappalardo, Luciano Libero, Paremuzyan, R., Park, S., Pereira, S. A., Phelps, E., Pisano, S., Pogorelko, O., Pozdniakov, S., Price, J. W., Procureur, S., Prok, Y., Ricco, G., Rimal, D., Ripani, M., Ritchie, B. G., Rosner, G., Rossi, P., Sabatie, F., Saini, M. S., Salgado, C., Schott, D., Schumacher, R. A., Seraydaryan, H., Sharabian, Y. G., Smith, E. S., Smith, G. D., Sober, D. I., Sokhan, D., Stepanyan, S. S., Stepanyan, S., Stoler, P., Strakovsky, I. I., Strauch, S., Taiuti, M., Tang, W., Taylor, C. E., Tian, Y., Tkachenko, S., Trivedi, A., Ungaro, M., Vernarsky, B., Vlassov, A. V., Voutier, E., Watts, D. P., Weygand, D. P., Wood, M. H., Zachariou, N., Zhao, B., and Zhao, Z. W.

Subjects
QUANTUM CHROMODYNAMICS, PI-0, PION ELECTROPRODUCTION, NUCLEONS, PROTON, PHOTOPRODUCTION, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2012

20. Experimental study of the P-11(1440) and D-13(1520) resonances from the CLAS data on ep -> e 'pi(+)pi(-)p

Author

Mokeev, V. I., Burkert, V. D., Elouadrhiri, L., Fedotov, G. V., Golovatch, E. N., Gothe, R. W., Ishkhanov, B. S., Isupov, E. L., Adhikari, K. P., Aghasyan, M., Anghinolfi, M., Avakian, H., Baghdasaryan, H., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Bookwalter, C., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Carman, D. S., Celentano, A., Charles, G., Cole, P. L., Contalbrigo, Marco, Crede, V., D'Angelo, A., Daniel, A., Dashyan, N., Vita, R. D., Sanctis, E. D., Deur, A., Djalali, C., Doughty, D., Dupre, R., Alaoui, A. E., Eugenio, P., Fegan, S., Fradi, A., Giovanetti, K. L., Girod, F. X., Gohn, W., Graham, L., Griffioen, K. A., Guegan, B., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Hicks, K., Ho, D., Holtrop, M., Ilieva, Y., Ireland, D. G., H. S., Jo, Joo, K., Keller, D., Khandaker, M., Khetarpal, P., Kim, A., Kim, W., Klein, A., Klein, F. J., Koirala, S., Kubarovsky, A., Kubarovsky, V., Kuleshov, S. V., Kvaltine, N. D., Livingston, K., H. Y., Lu, I. J. D., Mao, Y., Markov, N., Martinez, D., Mayer, M., Mckinnon, B., Meyer, C. A., Mineeva, T., Mirazita, M., Moutarde, H., Munevar, E., Nadel Turonski, P., Nepali, C. S., Ostrovidov, A. I., Pappalardo, Luciano Libero, Paremuzyan, R., Park, K., Park, S., Pasyuk, E., Pereira, S. A., Pisano, S., Pogorelko, O., Pozdniakov, S., Price, J. W., Procureur, S., Protopopescu, D., Raue, B. A., Ricco, G., Rimal, D., Ripani, M., Rosner, G., Rossi, P., Sabatie, F., Saini, M. S., Salgado, C., Schott, D., Schumacher, R. A., Seder, E., Seraydaryan, H., Sharabian, Y. G., Smith, G. D., Smith, L. C., Sober, D. I., Sokhan, D., Stepanyan, S., Stepanyan, S. S., Stoler, P., Strakovsky, I. I., Strauch, S., Tang, W., Taylor, C. E., Tian, Y., Tkachenko, S., Trivedi, A., Ungaro, M., Vineyard, M. F., Voskanyan, H., Voutier, E., Walford, N. K., Wood, M. H., Zachariou, N., Zhao, Z. W., and Zonta, I.

Subjects
NUCLEON FORM-FACTORS, BARYON RESONANCES, MESON PRODUCTION, PI-N SCATTERING, QUARK-MODEL, DECAYS, ELECTROPRODUCTION, REGION, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2012

21. Electromagnetic decay of the Sigma(0)(1385) to Lambda gamma

Author

Keller, D., Hicks, K., Adhikari, K. P., Adikaram, D., Aghasyan, M., Amarian, M., Baghdasaryan, H., Ball, J., Battaglieri, M., Batourine, V., Bedlinskiy, I., Bennett, R. P., Biselli, A. S., Branford, D., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Careccia, S. L., Carman, D. S., Casey, L., Cole, P. L., Contalbrigo, M., Crede, V., D'Angelo, A., Daniel, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Dey, B., Dickson, R., Djalali, C., Doughty, D., Dupre, R., Egiyan, H., El Alaoui, A., El Fassi, L., Eugenio, P., Fedotov, G., Fegan, S., Forest, T. A., Gabrielyan, M. Y., Gavalian, G., Gevorgyan, N., Giovanetti, K. L., Girod, F. X., Gohn, W., Golovatch, E., Gothe, R. W., Graham, L., Guidal, M., Guegan, B., Hafidi, K., Hakobyan, H., Hanretty, C., Holtrop, M., Ilieva, Y., Ireland, D. G., Isupov, E. L., Jawalkar, S. S., Jenkins, D., Jo, H. S., Joo, K., Khandaker, M., Khetarpal, P., Kim, A., Kim, W., Klein, A., Klein, F. J., Konczykowski, P., Kubarovsky, V., Kuleshov, S. V., Kuznetsov, V., Lu, H. Y., MacGregor, I. J. D., Markov, N., McAndrew, J., McKinnon, B., Meyer, C. A., Micherdzinska, A. M., Mirazita, M., Mokeev, V., Moreno, B., Moriya, K., Morrison, B., Moutarde, H., Munevar, E., Nadel-Turonski, P., Ni, A., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Paremuzyan, R., Park, K., Park, S., Pasyuk, E., Pereira, S. Anefalos, Pappalardo, L. L., Pisano, S., Pogorelko, O., Pozdniakov, S., Price, J. W., Procureur, S., Protopopescu, D., Raue, B. A., Ripani, M., Ritchie, B. G., Rosner, G., Rossi, P., Sabatie, F., Saini, M. S., Salgado, C., Schott, D., Schumacher, R. A., Seder, E., Seraydaryan, H., Sharabian, Y. G., Smith, E. S., Smith, G. D., Sober, D. I., Stepanyan, S. S., Stoler, P., Strakovsky, I. I., Strauch, S., Taiuti, M., Tang, W., Taylor, C. E., Vernarsky, B., Vineyard, M. F., Voutier, E., Weinstein, L. B., Watts, D. P., Wood, M. H., Zachariou, N., Zana, L., Zhao, B., and Zhao, Z. W.

Subjects
BARYONS, STRANGENESS, Electric and Magnetyic Moments, Leptonic, and radiative decays, Electromagnetic decays, Settore FIS/04 - Fisica Nucleare e Subnucleare, DECUPLET, semileptonic, Hyperons, HYPERONS, QUARK-MODEL, RADIATIVE DECAYS
Published
2011

22. Differential cross sections and recoil polarizations for the reaction γp→K^{+}Σ^{0}

Author

Dey, B, Meyer, C, Bellis, M, Mccracken, M, Williams, M, Adhikari, K, Aghasyan, M, Anghinolfi, M, Ball, J, Battaglieri, M, Batourine, V, Bedlinskiy, I, Berman, B, Biselli, A, Branford, D, Briscoe, W, Brooks, W, Burkert, V, Carman, D, Crede, V, D'Angelo, A, Daniel, A, De Vita, R, De Sanctis, E, Deur, A, Dhamija, S, Dickson, R, Djalali, C, Doughty, D, Dugger, M, Dupre, R, El Alaoui, A, El Fassi, L, Eugenio, P, Fegan, S, Fradi, A, Gabrielyan, M, Gilfoyle, G, Giovanetti, K, Girod, F, Gohn, W, Gothe, R, Graham, L, Griffioen, K, Guler, N, Guo, L, Hafidi, K, Hakobyan, H, Hanretty, C, Hassall, N, Hicks, K, Holtrop, M, Ilieva, Y, Ireland, D, Jawalkar, S, Jo, H, Joo, K, Keller, D, Khandaker, M, Khetarpal, P, Kim, A, Kim, W, Klein, A, Klein, F, Konczykowski, P, Kubarovsky, V, Kuleshov, S, Kuznetsov, V, Livingston, K, Macgregor, I, Martinez, D, Mcandrew, J, Mckinnon, B, Mikhailov, K, Mirazita, M, Mokeev, V, Moreno, B, Moriya, K, Morrison, B, Moutarde, H, Munevar, E, Nadel Turonski, P, Nasseripour, R, Nepali, C, Ni, A, Niccolai, S, Niculescu, G, Niculescu, I, Niroula, M, Osipenko, M, Ostrovidov, A, Paremuzyan, R, Park, K, Park, S, Pasyuk, E, Pereira, S, Pogorelko, O, Pozdniakov, S, Price, J, Procureur, S, Protopopescu, D, Raue, B, Ricco, G, Ripani, M, Ritchie, B, Rosner, G, Rossi, P, Salamanca, J, Salgado, C, Schott, D, Schumacher, R, Seder, E, Seraydaryan, H, Sharabian, Y, Smith, E, Smith, G, Sober, D, Sokhan, D, Stepanyan, S, Strakovsky, I, Strauch, S, Tang, W, Taylor, C, Tedeschi, D, Tkachenko, S, Ungaro, M, Watts, D, Vernarsky, B, Vineyard, M, Voutier, E, Weinstein, L, Wood, M, Yegneswaran, A, Zhang, J, Zhao, B, and Zhao, Z

Subjects
BARYON RESONANCES, MESON PHOTOPRODUCTION, SPIN OBSERVABLES, ENERGIES, SIGMA(0), LAMBDA, K+, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2010

23. Differential cross section and recoil polarization measurements for the γp→K^{+}Λ reaction using CLAS at Jefferson Lab

Author

Mccracken, M, Bellis, M, Meyer, C, Williams, M, Adhikari, K, Anghinolfi, M, Ball, J, Battaglieri, M, Berman, B, Biselli, A, Branford, D, Briscoe, W, Brooks, W, Burkert, V, Careccia, S, Carman, D, Cole, P, Collins, P, Crede, V, D'Angelo, A, Daniel, A, Dashyan, N, De Vita, R, De Sanctis, E, Deur, A, Dey, B, Dhamija, S, Dickson, R, Djalali, C, Doughty, D, Dugger, M, Dupre, R, El Alaoui, A, Eugenio, P, Fegan, S, Fradi, A, Gabrielyan, M, Giovanetti, K, Girod, F, Goetz, J, Gohn, W, Gothe, R, Griffioen, K, Guidal, M, Hafidi, K, Hakobyanm, H, Hanretty, C, Hassall, N, Hicks, K, Holtrop, M, Ilieva, Y, Ireland, D, Jo, H, Keller, D, Khandaker, M, Khetarpal, P, Kim, W, Klein, A, Klein, F, Kubarovsky, V, Kuleshov, S, Kuznetsov, V, Livingston, K, Mayer, M, Mcandrew, J, Mckinnon, B, Mestayer, M, Mineeva, T, Mirazita, M, Mokeev, V, Moreno, B, Moriya, K, Morrison, B, Moutarde, H, Munevar, E, Nadel Turonski, P, Niccolai, S, Niculescu, G, Niculescu, I, Osipenko, M, Ostrovidov, A, Park, K, Park, S, Pasyuk, E, Pereira, S, Perrin, Y, Pisano, S, Pogorelko, O, Pozdniakov, S, Price, J, Procureur, S, Prok, Y, Protopopescu, D, Quinn, B, Raue, B, Ricco, G, Ripani, M, Ritchie, B, Rosner, G, Rossi, P, Sabatie, F, Saini, M, Salamanca, J, Schott, D, Schumacher, R, Seder, E, Seraydaryan, H, Sharabian, Y, Sober, D, Sokhan, D, Stepanyan, S, Stoler, P, Strauch, S, Taiuti, M, Tedeschi, D, Tkachenko, S, Ungaro, M, Vernarsky, B, Vineyard, M, Watts, D, Voutier, E, Weinstein, L, Weygand, D, Wood, M, and Zana, L

Subjects
PHOTON ENERGIES, SIGMA(0), PHOTOPRODUCTION, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2010

24. Partial wave analysis of the reaction γp→pω and the search for nucleon resonances

Author

Williams, M, Applegate, D, Bellis, M, Meyer, C, Adhikari, K, Anghinolfi, M, Baghdasaryan, H, Ball, J, Battaglieri, M, Bedlinskiy, I, Berman, B, Biselli, A, Briscoe, W, Brooks, W, Burkert, V, Careccia, S, Carman, D, Cole, P, Collins, P, Crede, V, D'Angelo, A, Daniel, A, De Vita, R, De Sanctis, E, Deur, A, Dey, B, Dhamija, S, Dickson, R, Djalali, C, Dodge, G, Doughty, D, Dugger, M, Dupre, R, Alaoui, A, Elouadrhiri, L, Eugenio, P, Fedotov, G, Fegan, S, Fradi, A, Gabrielyan, M, Garçon, M, Gilfoyle, G, Giovanetti, K, Girod, F, Gohn, W, Golovatch, E, Gothe, R, Griffioen, K, Guidal, M, Guler, N, Guo, L, Hafidi, K, Hakobyan, H, Hanretty, C, Hassall, N, Hicks, K, Holtrop, M, Ilieva, Y, Ireland, D, Ishkhanov, B, Isupov, E, Jawalkar, S, Jo, H, Johnstone, J, Joo, K, Keller, D, Khandaker, M, Khetarpal, P, Kim, W, Klein, A, Klein, F, Krahn, Z, Kubarovsky, V, Kuleshov, S, Kuznetsov, V, Livingston, K, Lu, H, Mayer, M, Mcandrew, J, Mccracken, M, Mckinnon, B, Mirazita, M, Mokeev, V, Moreno, B, Moriya, K, Morrison, B, Munevar, E, Nadel Turonski, P, Nepali, C, Niccolai, S, Niculescu, G, Niculescu, I, Niroula, M, Niyazov, R, Osipenko, M, Ostrovidov, A, Paris, M, Park, K, Park, S, Pasyuk, E, Pereira, S, Perrin, Y, Pisano, S, Pogorelko, O, Pozdniakov, S, Price, J, Procureur, S, Protopopescu, D, Ricco, G, Ripani, M, Ritchie, B, Rosner, G, Rossi, P, Sabatié, F, Saini, M, Salamanca, J, Salgado, C, Schott, D, Schumacher, R, Seraydaryan, H, Sharabian, Y, Smith, E, Sober, D, Sokhan, D, Stepanyan, S, Stoler, P, Strakovsky, I, Strauch, S, Taiuti, M, Tedeschi, D, Tkachenko, S, Ungaro, M, Vineyard, M, Voutier, E, Watts, D, Weygand, D, Wood, M, Zhang, J, and Zhao, B

Subjects
MODEL, GEV-C, DIFFRACTION DISSOCIATION, CLAS, PI-PI-DYNAMICS, COUPLED-CHANNEL, POLARIZED PHOTONS, HIGH-STATISTICS, SYSTEM, CHAMBER, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2009

25. Differential cross sections and spin density matrix elements for the reaction gamma p -> p omega

Author

Williams, M, Applegate, D, Bellis, M, Meyer, C, Adhikari, K, Anghinolfi, M, Baghdasaryan, H, Ball, J, Battaglieri, M, Bedlinskiy, I, Berman, B, Biselli, A, Bookwalter, C, Briscoe, W, Brooks, W, Burkert, V, Careccia, S, Carman, D, Cole, P, Collins, P, Crede, V, D'Angelo, A, Daniel, A, De Vita, R, De Sanctis, E, Deur, A, Dey, B, Dhamija, S, Dickson, R, Djalali, C, Dodge, G, Doughty, D, Dugger, M, Dupre, R, El Alaoui, A, Elouadrhiri, L, Eugenio, P, Fedotov, G, Fegan, S, Fradi, A, Gabrielyan, M, Garcon, M, Gevorgyan, N, Gilfoyle, G, Giovanetti, K, Girod, F, Gohn, W, Golovatch, E, Gothe, R, Griffioen, K, Guidal, M, Guo, L, Hafidi, K, Hakobyan, H, Hanretty, C, Hassall, N, Hicks, K, Holtrop, M, Ilieva, Y, Ireland, D, Ishkhanov, B, Isupov, E, Jawalkar, S, Jo, H, Johnstone, J, Joo, K, Keller, D, Khandaker, M, Khetarpal, P, Kim, W, Klein, A, Klein, F, Krahn, Z, Kubarovsky, V, Kuleshov, S, Kuznetsov, V, Livingston, K, Lu, H, Mayer, M, Mcandrew, J, Mccracken, M, Mckinnon, B, Mikhailov, K, Mirazita, M, Mokeev, V, Moreno, B, Moriya, K, Morrison, B, Moutarde, H, Munevar, E, Nadel Turonski, P, Nepali, C, Niccolai, S, Niculescu, G, Niculescu, I, Niroula, M, Niyazov, R, Osipenko, M, Ostrovidov, A, Paris, M, Park, K, Park, S, Pasyuk, E, Pereira, S, Perrin, Y, Pisano, S, Pogorelko, O, Pozdniakov, S, Price, J, Procureur, S, Protopopescu, D, Raue, B, Ricco, G, Ripani, M, Ritchie, B, Rosner, G, Rossi, P, Sabatie, F, Saini, M, Salamanca, J, Salgado, C, Schott, D, Schumacher, R, Seraydaryan, H, Sharabian, Y, Smith, E, Sober, D, Sokhan, D, Stepanyan, S, Stoler, P, Strakovsky, I, Strauch, S, Taiuti, M, Tedeschi, D, Tkachenko, S, Ungaro, M, Vineyard, M, Voutier, E, Watts, D, Weinstein, L, Weygand, D, Wood, M, Zhang, J, and Zhao, B

Subjects
OMEGA, POLARIZED PHOTONS, VECTOR-MESONS, PHOTOPRODUCTION, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2009

26. Differential cross sections for the reactions gamma p -> p eta and gamma p -> p eta '

Author

Williams, M, Krahn, Z, Applegate, D, Bellis, M, Meyer, C, Adhikari, K, Anghinolfi, M, Baghdasaryan, H, Ball, J, Battaglieri, M, Bedlinskiy, I, Berman, B, Biselli, A, Bookwalter, C, Briscoe, W, Brooks, W, Burkert, V, Careccia, S, Carman, D, Cole, P, Collins, P, Crede, V, D'Angelo, A, Daniel, A, De Vita, R, De Sanctis, E, Deur, A, Dey, B, Dhamija, S, Dickson, R, Djalali, C, Dodge, G, Doughty, D, Dugger, M, Dupre, R, El Alaoui, A, Elouadrhiri, L, Eugenio, P, Fegan, S, Fradi, A, Gabrielyan, M, Garcon, M, Gilfoyle, G, Giovanetti, K, Girod, F, Gohn, W, Golovatch, E, Gothe, R, Griffioen, K, Guidal, M, Guler, N, Guo, L, Hafidi, K, Hakobyan, H, Hanretty, C, Hassall, N, Hicks, K, Holtrop, M, Ilieva, Y, Ireland, D, Ishkhanov, B, Isupov, E, Jawalkar, S, Jo, H, Johnstone, J, Joo, K, Keller, D, Khandaker, M, Khetarpal, P, Kim, W, Klein, A, Klein, F, Kubarovsky, V, Kuleshov, S, Kuznetsov, V, Livingston, K, Lu, H, Mayer, M, Mcandrew, J, Mccracken, M, Mckinnon, B, Mikhailov, K, Mineeva, T, Mirazita, M, Mokeev, V, Moriya, K, Morrison, B, Munevar, E, Nadel Turonski, P, Nepali, C, Niccolai, S, Niculescu, G, Niculescu, I, Niroula, M, Niyazov, R, Osipenko, M, Ostrovidov, A, Park, K, Park, S, Pasyuk, E, Pereira, S, Perrin, Y, Pieschacon, D, Pisano, S, Pogorelko, O, Pozdniakov, S, Price, J, Procureur, S, Prok, Y, Protopopescu, D, Raue, B, Ricco, G, Ripani, M, Ritchie, B, Rosner, G, Rossi, P, Sabatie, F, Saini, M, Salamanca, J, Salgado, C, Schott, D, Schumacher, R, Seraydaryan, H, Sharabian, Y, Smith, E, Sober, D, Sokhan, D, Stepanyan, S, Stoler, P, Strakovsky, I, Strauch, S, Taiuti, M, Tedeschi, D, Tkachenko, S, Ungaro, M, Vineyard, M, Voutier, E, Watts, D, Weinstein, L, Weygand, D, Wood, M, Zhang, J, and Zhao, B

Subjects
PHOTOPRODUCTION, Settore FIS/04 - Fisica Nucleare e Subnucleare
Published
2009

27. Measurement of the Q² Dependence of the Deuteron Spin Structure Function g1 and its Moments at Low Q² with CLAS.

Author

Adhikari, K. P.

Subjects
*DEUTERONS, *MOLECULAR structure, *NUCLEAR spin, *SPECTRUM analysis
Abstract

We measured the g1 spin structure function of the deuteron at low Q², where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W≈1.9 GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γd1 and the spin polarizability γd0 are precisely determined down to a minimum Q² of 0.02 GeV² for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a program of benchmark measurements of polarization observables in the χPT domain. [ABSTRACT FROM AUTHOR]

Published
2018
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28. Strangeness Suppression of qq Creation Observed in Exclusive Reactions.

Author

Mestayer, M. D., Park, K., Adhikari, K. P., Aghasyan, M., Anefalos Pereira, S., Ball, J., Battaglieri, M, Batourine, V., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Cannan, D. S., Celentano, A., Chandavar, S., Charles, G., Colaneri, L., and Cole, P. L.

Subjects
*STRANGE particles, *EXCLUSIVE reactions (Nuclear physics), *MESONS, *BARYONS, *QUARKS
Abstract

We measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ΛK+, pπ0, and ππ+, with the CLAS detector at Jefferson Lab. Using a simple model of quark hadronization, we extract qq creation probabilities for the first time in exclusive two-body production, in which only a single qq pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to nonstrange pairs, similar to that seen in high-energy production. [ABSTRACT FROM AUTHOR]

Published
2014
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29. Search for baryon-number and lepton-number violating decays of A hyperons using the CL AS detector at Jefferson Laboratory.

Author

McCracken, M. E., Bellis, M., Adhikari, K. P., Adikaram, D., Akbar, Z., Anefalos Pereira, S., Badui, R. A., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Cao, T., Carman, D. S., and Celentano, A.

Subjects
*BARYON number, *LEPTON number, *RADIOACTIVE decay, *HYPERONS, *NUCLEAR counters, *BRANCHING ratios
Abstract

We present a search for ten baryon number violating decay modes of Λ hyperons using the CLAS detector at Jefferson Laboratory. Nine of these decay modes result in a single meson and single lepton in the final state (Λ→ml) and conserve either the sum or the difference of baryon and lepton number (B±L). The tenth decay mode (Λ→p¯π+) represents a difference in baryon number of two units and no difference in lepton number. We observe no significant signal and set upper limits on the branching fractions of these reactions in the range (4-200)×10-7 at the 90% confidence level. [ABSTRACT FROM AUTHOR]

Published
2015
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30. Measurement of the Σπ photoproduction line shapes near the Λ(1405).

Author

Moriya, K., Schumacher, R. A., Adhikari, K. P., Adikaram, D., Aghasyan, M., Anderson, M. D., Pereira, S. Anefalos, Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Bellis, M., Biselli, A. S., Bono, J., Boiarinov, S., Briscoe, W. J., Burkert, V. D., Carman, D. S., and Celentano, A.

Subjects
*REST mass (Relativity), *PHOTONS, *SHEAR waves, *ISOBARIC spin
Abstract

The reaction γ+p→K++Σ+π was used to determine the invariant mass distributions or "line shapes" of the Σ+π-, Σ-π+, and Σ0π0 final states, from threshold at 1328 MeV/c² through the mass range of the Λ(1405) and the Λ(1520). The measurements were made with the CLAS system at Jefferson Lab using tagged real photons, for center-of-mass energies 1.95

Published
2013
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31. Coherent photoproduction of π+ from 3He.

Author

Nasseripour, R., Berman, B. L., Adhikari, K. P., Adikaram, D., Anghinolfi, M., Ball, J., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Branford, D., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Carman, D. S., Casey, L., Cole, P. L., Collins, P., Crede, V., and D'Angelo, A.

Subjects
*COHERENCE (Nuclear physics), *BREMSSTRAHLUNG, *PIONS, *PHOTOPIONS, *PHOTON beams, *PARTICLES (Nuclear physics), SCATTERING
Abstract

We have measured the differential cross section for the γ3He→π+t reaction. This reaction was studied using the Continuous Electron Beam Accelerator Facility (CEBAF) Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Real photons produced with the Hall-B bremsstrahlung tagging system in the energy range from 0.50 to 1.55 GeV were incident on a cryogenic liquid 3He target. The differential cross sections for the γ3He→π+t reaction were measured as a function of photon-beam energy and pion-scattering angle. Theoretical predictions to date cannot explain the large cross sections except at backward angles, showing that additional components must be added to the model. [ABSTRACT FROM AUTHOR]

Published
2011
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32. Cross Sections for the Exclusive Photon Electroproduction on the Proton and Generalized Parton Distributions.

Author

Jo, H. S., Girod, F. X., Avakian, H., Burkert, V. D., Garçon, M., Guidal, M., Kubarovsky, V., Niccolai, S., Stoler, P., Adhikari, K. P., Adikaram, D., Amaryan, M. J., Anderson, M. D., Pereira, S. Anefalos, Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., and Biselli, A. S.

Subjects
*NUCLEAR cross sections, *PHOTONS, *PROTONS, *PARTONS, *POLARIZED electrons
Abstract

Unpolarized and beam-polarized fourfold cross sections (d4σ/dQ2dxBdtdϕ) for the ep → e'p'γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q2,xB, t) bins over the widest phase space ever explored in the valencequark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H, expected to be the dominant contributor to these observables. Through a leading-twist extraction of Compton form factors, these results support the model predictions of a larger nucleon size at lower quark-momentum fraction xB. [ABSTRACT FROM AUTHOR]

Published
2015
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33. Precise determination of the deuteron spin structure at low to moderate Q² with CLAS and extraction of the neutron contribution.

Author

Guler, N., Fersch, R. G., Kuhn, S. E., Bosted, P., Griffioen, K. A., Keith, C., Minehart, R., Prok, Y., Adhikari, K. P., Adikaram, D., Amaryan, M. J., Anderson, M. D., Anefalos Pereira, S., Avakian, H., Ball, J., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A., and Briscoe, W. J.

Subjects
*NEUTRON spin, *ELECTRON beam research, *DEUTERON scattering, *POLARIZED electrons, *SPECTROMETERS
Abstract

We present the final results for the deuteron spin structure functions obtained from the full data set collected in 2000-2001 with Jefferson Lab's continuous electron beam accelerator facility (CEBAF) using the CEBAF large acceptance spectrometer (CLAS). Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.8 GeV were scattered from deuteron (I5ND3) targets, dynamically polarized along the beam direction, and detected with CLAS. From the measured double-spin asymmetry, the virtual photon absorption asymmetry A1d and the polarized structure function g1d were extracted over a wide kinematic range (0.05 GeV² < Q² < 5 GeV² and 0.9 GeV < W < 3 GeV). We use an unfolding procedure and a parametrization of the corresponding proton results to extract from these data the polarized structure functions A1n and g1n of the (bound) neutron, which are so far unknown in the resonance region, W < 2 GeV. We compare our final results, including several moments of the deuteron and neutron spin structure functions, with various theoretical models and expectations, as well as parametrizations of the world data. The unprecedented precision and dense kinematic coverage of these data can aid in future extractions of polarized parton distributions, tests of perturbative QCD predictions for the quark polarization at large x, a better understanding of quark-hadron duality, and more precise values for higher-twist matrix elements in the framework of the operator product expansion. [ABSTRACT FROM AUTHOR]

Published
2015
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34. Measurements of ep -> e'π+n at 1.6 < W < 2.0 GeV and extraction of nucleon resonance electrocouplings at CLAS.

Author

Park, K., Aznauryan, I. G., Burkerl, V. D., Adhikari, K. P., Amaryan, M. J., Anefalos Pereira, S., Avakian, H., Battaglieri, M., Badui, R., Bedlinskiy, I., Biselli, A. S., Bono, J., Briscoe, W. J., Brooks, W. K., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Colaneri, L., and Cole, P. L.

Subjects
*NUCLEAR resonance reactions, *SPECTROMETERS, *SPIN-spin interactions, *NUCLEAR isobars, *NUCLEAR research
Abstract

Differential cross sections of the exclusive process ep -> e'π+n were measured with good precision in the range of the π+n photon virtuality Q²=1.8-4.5 GeV², and the invariant mass range of the final state W=1.6-2.0 GeV using the CEBAF Large Acceptance Spectrometer. Data were collected with nearly complete coverage in the azimuthal and polar angles of the np+ center-of-mass system. More than 37,000 cross section points were measured. The contributions of the isospin I=1/2 resonances N(1675)5-/2, N(1680)5+/2 and N(1710)1+/2 were extracted at different values of Q² using a single-channel, energy-dependent resonance amplitude analysis. Two different approaches, the unitary isobar model and the fixed-t dispersion relations, were employed in the analysis. We observe significant strength of the N(1675)5-/2 in the A1/2 amplitude, which is in strong disagreement with quark models that predict both transverse amplitudes to be strongly suppressed. For the N(1680)5+/2 we observe a slow changeover from the dominance of the A3/2 amplitude at the real photon point (Q²=0) to a Q² where A1/2 begins to dominate. The scalar amplitude S1/2 drops rapidly with Q2 consistent with quark model prediction. For the N(1710)1+/2 resonance our analysis shows significant strength for the A1/2 amplitude at Q²<2.5 GeV². [ABSTRACT FROM AUTHOR]

Published
2015
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35. Towards a Resolution of the Proton Form Factor Problem: New Electron and Positron Scattering Data.

Author

Adikaram, D., Rimal, D., Weinstein, L. B., Raue, B., Khetarpal, P., Bennett, R. P., Arrington, J., Brooks, W. K., Adhikari, K. P., Afanasev, A. V., Amaryan, M. J., Anderson, M. D., Anefalos Pereira, S., Avakian, H., Ball, J., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Bono, J., and Boiarinov, S.

Subjects
*POSITRON scattering, *DATA analysis, *SCATTERING (Physics), *PROTONS, *BARYONS
Abstract

There is a significant discrepancy between the values of the proton electric form factor, GPE, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of GPE from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (ε) and momentum transfer (Q2) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ε at Q2 = 1.45 GeV2. This measurement is consistent with the size of the form factor discrepancy at Q2 ≈ 1.75 GeV2 and with hadronic calculations including nucleon and Δ intermediate states, which have been shown to resolve the discrepancy up to 2-3 GeV2. [ABSTRACT FROM AUTHOR]

Published
2015
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36. Longitudinal Target-Spin Asymmetries for Deeply Virtual Compton Scattering.

Author

Seder, E., Biselli, A., Pisano, S., Niccolai, S., Smith, G. D., Joo, K., Adhikari, K., Amaryan, M. J., Anderson, M. D., Anefalos Pereira, S., Avakian, H., Battaglieri, M., Bedlinskiy, I., Bono, J., Boiarinov, S., Bosted, P., Briscoe, W., Brock, J., Brooks, W. K., and Bültmann, S.

Subjects
*COMPTON scattering, *PHOTONS, *SPATIAL distribution (Quantum optics), *PROTONS, *SPECTROMETERS
Abstract

A measurement of the electroproduction of photons off protons in the deeply inelastic regime was performed at Jefferson Lab using a nearly 6 GeV electron beam, a longitudinally polarized proton target, and the CEBAF Large Acceptance Spectrometer. Target-spin asymmetries for ep → e'p'γ events, which arise from the interference of the deeply virtual Compton scattering and the Bethe-Heitler processes, were extracted over the widest kinematics in Q2,xB,t, and ϕ, for 166 four-dimensional bins. In the framework of generalized parton distributions, at leading twist the t dependence of these asymmetries provides insight into the spatial distribution of the axial charge of the proton, which appears to be concentrated in its center. These results also bring important and necessary constraints for the existing parametrizations of chiral-even generalized parton distributions. [ABSTRACT FROM AUTHOR]

Published
2015
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37. Induced polarization of A(1116) in kaon electroproduction.

Author

Gabrielyan, M., Raue, B. A., Carman, D. S., Park, K., Adhikari, K. P., Adikaram, D., Amaryan, M. J., Anefalos Pereira, S., Avakian, H., Ball, J., Baltzell, N. A., Battaglieri, M., Baturin, V., Bedlinskiy, I., Biselli, A. S., Bono, J., Boiarinov, S., Briscoe, W. J., Brooks, W. K., and Burkert, V. D.

Subjects
*POLARIZATION (Nuclear physics), *SCATTERING (Physics), *ELECTRON beam research, *KAONS, *MOMENTUM transfer
Abstract

We have measured, the induced polarization of the A( 1116) in the reaction ep →e' K+ Λ, detecting the scattered e' and K + in the final state along with the proton from the decay ΛA → pπ-. The present study used the CEBAF Large Acceptance Spectrometer (CLAS), which allowed for a large kinematic acceptance in invariant energy W (1.6 ≤ W ≤ 2.7 GeV) and covered the full range of the kaon production angle at an average momentum transfer Q² = 1.90 GeV². In this experiment a 5.50-GeV electron beam was incident upon an unpolarized liquid-hydrogen target. We have mapped out the W and kaon production angle dependencies of the induced polarization and found striking differences from photoproduction data over most of the kinematic range studied. However, we also found that the induced polarization is essentially Q² independent in our kinematic domain, suggesting that somewhere below the Q² covered here there must be a strong Q² dependence. Along with previously published photo- and electroproduction cross sections and polarization observables, these data are needed for the development of models, such as effective field theories, and as input to coupled-channel analyses that can provide evidence of previously unobserved s-channel resonances. [ABSTRACT FROM AUTHOR]

Published
2014
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38. Precision measurements of g1 of the proton and of the deuteron with 6 GeV electrons.

Author

Prok, Y., Bosted, P., Kvaltine, N., Adhikari, K. P., Adikaram, D., Aghasyan, M., Amaryan, M. J., Anderson, M. D., Pereira, S. Anefalos, Avakian, H., Baghdasaryan, H., Ball, J., Baltzell, N. A., Battaglieri, M., Biselli, A. S., Bono, J., Briscoe, W. J., Brock, J., Brooks, W. K., and Bültmann, S.

Subjects
*DEUTERONS, *POLARIZATION (Nuclear physics), *MAGNETIC resonance, *QUANTUM chromodynamics, *REST mass (Relativity)
Abstract

The inclusive polarized structure functions of the proton and deuteron, g1p and g1d, were measured with high statistical precision using polarized 6 GeV electrons incident on a polarized ammonia target in Hall B at Jefferson Laboratory. Electrons scattered at laboratory angles between 18 and 45 degrees were detected using the CEBAF Large Acceptance Spectrometer (CLAS). For the usual deep inelastic region kinematics, Q² > 1 GeV² and the final-state invariant mass W>2 GeV, the ratio of polarized to unpolarized structure functions g1/F1 is found to be nearly independent of Q² at fixed x. Significant resonant structure is apparent at values of W up to 2.3 GeV. In the framework of perturbative quantum chromodynamics, the high-W results can be used to better constrain the polarization of quarks and gluons in the nucleon, as well as highontributions. [ABSTRACT FROM AUTHOR]

Published
2014
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39. ɸ-meson photoproduction on hydrogen in the neutral decay mode.

Author

Seraydaryan, H., Amaryan, M. J., Gavalian, G., Baghdasaryan, H., Weinstein, L., Adhikari, K. P., Adikaram, D., Aghasyan, M., Anderson, M. D., Pereira, S. Anéfalos, Avakian, H., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Bennett, R. P., Biselli, A. S., Bono, J., and Boiarinov, S.

Subjects
*HYDROGEN, *NUCLEAR cross sections, *PHOTON beams, MESON spectra, MESON decay
Abstract

We report the first measurement of the photoproduction cross section of the ɸ meson in its neutral decay mode in the reaction γp → pɸ(KSKL). The experiment was performed with a tagged photon beam of energy 1.6 = Eγ = 3.6 GeV incident on a liquid hydrogen target of the CLAS spectrometer at the Thomas Jefferson National Accelerator Facility. The pɸ final state is identified via reconstruction of KS in the invariant mass of two oppositely charged pions and by requiring the missing particle in the reaction γp → pKSX to be KL. The presented results significantly enlarge the existing data on ɸ photoproduction. These data, combined with the data from the charged decay mode, will help to constrain different mechanisms of ɸ photoproduction. [ABSTRACT FROM AUTHOR]

Published
2014
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40. Data analysis techniques, differential cross sections, and spin density matrix elements for the reaction γp → ɸp.

Author

Dey, B., Meyer, C. A., Bellis, M., Williams, M., Adhikari, K. P., Adikaram, D., Aghasyan, M., Amaryan, M. J., Anderson, M. D., Pereira, S. Anefalos, Ball, J., Baltzell, N. A., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Bono, J., Boiarinov, S., Briscoe, W. J., Brooks, W. K., and Burkert, V. D.

Subjects
*DIFFERENTIAL cross sections, *DATA analysis, *DENSITY matrices, *NUCLEAR reactions, *MOMENTUM distributions
Abstract

High-statistics measurements of differential cross sections and spin density matrix elements for the reaction γp → ɸp have been made using the CLAS detector at Jefferson Lab. We cover center-of-mass energies (sv) from 1.97 to 2.84 GeV, with an extensive coverage in the ɸ production angle. The high statistics of the data sample made it necessary to carefully account for the interplay between the ɸ natural lineshape and effects of the detector resolution, that are found to be comparable in magnitude. We study both the charged- (ɸ → K+K-) and neutral- (ɸ → KS0KL0) KK decay modes of the ɸ. Further, for the charged mode, we differentiate between the cases where the final K track is directly detected or its momentum reconstructed as the total missing momentum in the event. The two charged-mode topologies and the neutral-mode have different resolutions and are calibrated against each other. Extensive usage is made of kinematic fitting to improve the reconstructed ɸ mass resolution. Our final results are reported in 10- and mostly 30-MeV-wide s√ bins for the charged- and the neutral-modes, respectively. Possible effects from K+Λ* channels with pKK final states are discussed. These present results constitute the most precise and extensive ɸ photoproduction measurements to date and in conjunction with the ω photoproduction results recently published by CLAS, will greatly improve our understanding of low energy vector meson photoproduction. [ABSTRACT FROM AUTHOR]

Published
2014
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41. Single and double spin asymmetries for deeply virtual Compton scattering measured with CLAS and a longitudinally polarized proton target.

Author

Pisano, S., Biselli, A., Niccolai, S., Seder, E., Guidai, M., Mirazita, M., Adhikari, K. P., Adikaram, D., Amaryan, M. J., Anderson, M. D., Pereira, S. Anefalos, Avakian, H., Ball, J., Battaglieri, M., Batourine, V., Bedlinskiy, I., Bosted, P., Briscoe, B., Brock, J., and Brooks, W. K.

Subjects
*COMPTON scattering, *KINEMATICS, *QUANTUM chromodynamics, *PARTONS, *PARTICLES (Nuclear physics)
Abstract

Single-beam, single-target, and double spin asymmetries for hard exclusive electroproduction of a photon on the proton ep → epγ are presented. The data were taken at Jefferson Lab using the CEBAF large acceptance spectrometer and a longitudinally polarized 14NH3 target. The three asymmetries were measured in 165 four-dimensional kinematic bins, covering the widest kinematic range ever explored simultaneously for beam and target-polarization observables in the valence quark region. The kinematic dependences of the obtained asymmetries are discussed and compared to the predictions of models of generalized parton distributions. The measurement of three DVCS spin observables at the same kinematic points allows a quasi-model-independent extraction of the imaginary parts of the H and H Compton form factors, which give insight into the electric and axial charge distributions of valence quarks in the proton. [ABSTRACT FROM AUTHOR]

Published
2015
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42. Hard Two-Body Photodisintegration of ³He.

Author

Pomerantz, I., Ilieva, Y., Gilman, R., Higinbotham, D. W., Piasetzky, E., Strauch, S., Adhikari, K. P., Aghasyan, M., Allada, K., Amaryan, M. J., Anefalos Pereira, S., Anghinolfi, M., Baghdasaryan, H., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Beck, A., Beck, S., and Bedlinskiy, I.

Subjects
*PHOTODISINTEGRATION, *PHOTONS, *CENTER of mass, *DEUTERONS, *MOMENTUM transfer, *ASYMPTOTIC freedom
Abstract

We have measured cross sections for the γ³He → pd reaction at photon energies of 0.4-1.4 GeV and a center-of-mass angle of 90°. We observe dimensional scaling above 0.7 GeV at this center-of-mass angle. This is the first observation of dimensional scaling in the photodisintegration of a nucleus heavier than the deuteron. [ABSTRACT FROM AUTHOR]

Published
2013
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43. Separated structure functions for exclusive K+Λ and K+Σ0 electroproduction at 5.5 GeV measured with CLAS.

Author

Carman, D. S., Park, K., Raue, B. A., Adhikari, K. P., Adikaram, D., Aghasyan, M., Amaryan, M. J., Anderson, M. D., Pereira, S. Anefalos, Anghinolfi, M., Avakian, H., Baghdasaryan, H., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Bono, J., and Boiarinov, S.

Subjects
*ELECTRON beam research, *CENTER of mass, *KAONS, *MESONS, *BARYONS
Abstract

We report measurements of the exclusive electroproduction of K+Λ and K+Σ0 final states from an unpolarized proton target using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The separated structure functions σU, σLT, σTT, and σLT' were extracted from the Φ-dependent differential cross sections acquired with a longitudinally polarized 5.499 GeV electron beam. The data span a broad range of momentum transfers Q² from 1.4 to 3.9 GeV², invariant energy W from threshold to 2.6 GeV, and nearly the full center-of-mass angular range of the kaon. The separated structure functions provide an unprecedented data sample, which, in conjunction with other meson photo- and electroproduction data, will help to constrain the higher-level analyses being performed to search for missing baryon resonances. [ABSTRACT FROM AUTHOR]

Published
2013
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44. Beam-spin asymmetries from semi-inclusive pion electroproduction.

Author

Gohn, W., Avakian, H., Joo, K., Ungaro, M., Adhikari, K. P., Aghasyan, M., Amaryan, M. J., Anderson, M. D., Pereira, S. Anefalos, Ball, J., Baltzell, N. A., Battaglieri, M., Biselli, A. S., Bono, J., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Carman, D. S., Celentano, A., and Chandavar, S.

Subjects
*INELASTIC scattering, *QUARK-gluon interactions, *ELECTRON beams, *PIONS, *LIQUID hydrogen, *POLARIZATION (Nuclear physics), *SYMMETRY (Physics)
Abstract

We have measured the moment ALUsinɸ corresponding to the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering. ALUsinɸ is a twist-3 quantity providing information about quark-gluon correlations. Data were taken with the CLAS Spectrometer at Jefferson Lab using a 5.498 GeV longitudinally polarized electron beam and an unpolarized liquid hydrogen target. All three pion channels (π+, π0 and π-) were measured simultaneously over a large range of kinematics within the virtuality range Q²≈ 1.0-4.5 GeV². The observable was measured with better than 1% statistical precision over a large range of z, PT, xB, and Q², which permits comparison with several reaction models. The discussed measurements provide an upgrade in statistics over previous measurements, and serve as the first evidence for the negative sign of the π² sinɸ moment. [ABSTRACT FROM AUTHOR]

Published
2014
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45. Publisher's Note: Data analysis techniques, differential cross sections, and spin density matrix elements for the reaction γp → ɸp [Phys. Rev. C 89,055208 (2014)].

Author

Dey, B., Meyer, C. A., Bellis, M., Williams, M., Adhikari, K. P., Adikaram, D., Aghasyan, M., Amaryan, M. J., Anderson, M. D., Anefalos Pereira, S., Ball, J., Baltzell, N. A., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Bono, J., Boiarinov, S., Briscoe, W. J., Brooks, W. K., and Burkert, V. D.

Subjects
*DATA analysis, *DENSITY matrices
Abstract

A correction to the article " Data analysis techniques, differential cross sections, and spin density matrix elements for the reaction yp - ɸ p" that was published online in the May 27, 2014 issue is presented.

Published
2014
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46. First Measurement of Λ Electroproduction off Nuclei in the Current and Target Fragmentation Regions.

Author

Chetry T, El Fassi L, Brooks WK, Dupré R, El Alaoui A, Hafidi K, Achenbach P, Adhikari KP, Akbar Z, Armstrong WR, Arratia M, Atac H, Avakian H, Baashen L, Baltzell NA, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benkel B, Benmokhtar F, Bianconi A, Biselli AS, Bondi M, Booth WA, Bossù F, Boiarinov S, Brinkmann KT, Briscoe WJ, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chesnokov V, Ciullo G, Cole PL, Contalbrigo M, Costantini G, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Djalali C, Egiyan H, Elouadrhiri L, Eugenio P, Fegan S, Filippi A, Gavalian G, Ghandilyan Y, Gilfoyle GP, Glazier DI, Golubenko AA, Gosta G, Gothe RW, Griffioen KA, Guidal M, Guo L, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Hobart A, Holtrop M, Ilieva Y, Ireland DG, Isupov EL, Jenkins D, Jo HS, Kabir ML, Khanal A, Khandaker M, Kim A, Kim W, Klein FJ, Kripko A, Kubarovsky V, Lagerquist V, Lanza L, Leali M, Lee S, Lenisa P, Li X, Livingston K, MacGregor IJD, Marchand D, Mascagna V, McKinnon B, McLauchlin C, Meziani ZE, Migliorati S, Mineeva T, Mirazita M, Mokeev V, Munoz Camacho C, Nadel-Turonski P, Neupane K, Niccolai S, Nicol M, Niculescu G, Osipenko M, Ostrovidov AI, Pandey P, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Paul SJ, Phelps W, Pilleux N, Pokhrel M, Poudel J, Price JW, Prok Y, Raue BA, Reed T, Richards J, Ripani M, Ritman J, Rosner G, Sabatié F, Salgado C, Schadmand S, Schmidt A, Schumacher RA, Sharabian YG, Shirokov EV, Shrestha U, Simmerling P, Sokhan D, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Tan JA, Trotta N, Tyson R, Ungaro M, Vallarino S, Venturelli L, Voskanyan H, Voutier E, Wei X, Weinstein LB, Williams R, Wishart R, Wood MH, Yurov M, Zachariou N, Zhao ZW, and Zurek M

Abstract

We report results of Λ hyperon production in semi-inclusive deep-inelastic scattering off deuterium, carbon, iron, and lead targets obtained with the CLAS detector and the Continuous Electron Beam Accelerator Facility 5.014 GeV electron beam. These results represent the first measurements of the Λ multiplicity ratio and transverse momentum broadening as a function of the energy fraction (z) in the current and target fragmentation regions. The multiplicity ratio exhibits a strong suppression at high z and an enhancement at low z. The measured transverse momentum broadening is an order of magnitude greater than that seen for light mesons. This indicates that the propagating entity interacts very strongly with the nuclear medium, which suggests that propagation of diquark configurations in the nuclear medium takes place at least part of the time, even at high z. The trends of these results are qualitatively described by the Giessen Boltzmann-Uehling-Uhlenbeck transport model, particularly for the multiplicity ratios. These observations will potentially open a new era of studies of the structure of the nucleon as well as of strange baryons.

Published
2023
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47. Improved Λp Elastic Scattering Cross Sections between 0.9 and 2.0  GeV/c as a Main Ingredient of the Neutron Star Equation of State.

Author

Rowley J, Compton N, Djalali C, Hicks K, Price J, Zachariou N, Adhikari KP, Armstrong WR, Atac H, Baashen L, Barion L, Bashkanov M, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biondo L, Biselli AS, Bondi M, Bossù F, Boiarinov S, Briscoe WJ, Brooks WK, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chesnokov V, Chetry T, Ciullo G, Clark L, Cole PL, Contalbrigo M, Costantini G, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Dupré R, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Eugenio P, Fedotov G, Fegan S, Fersch R, Filippi A, Fradi A, Gavalian G, Girod FX, Glazier DI, Golubenko A, Gothe RW, Griffioen K, Guo L, Hafidi K, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Hobart A, Holtrop M, Ilieva Y, Ireland DG, Isupov EL, Jenkins D, Jo HS, Joo K, Keller D, Khanal A, Khandaker M, Kim A, Korover I, Kripko A, Kubarovsky V, Kuhn SE, Lanza L, Leali M, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Markov N, Marsicano L, Mascagna V, McCracken ME, McKinnon B, McLauchlin C, Meziani ZE, Migliorati S, Mineeva T, Mirazita M, Mokeev V, Munevar E, Munoz Camacho C, Nadel-Turonski P, Neupane K, Niccolai S, Niculescu G, O'Connell TR, Osipenko M, Ostrovidov AI, Pandey P, Paolone M, Pappalardo LL, Pasyuk E, Pogorelko O, Prok Y, Reed T, Ripani M, Ritman J, Rizzo A, Rosner G, Sabatie F, Salgado C, Schmidt A, Schumacher RA, Sharabian YG, Shrestha U, Sokhan D, Soto O, Sparveris N, Strakovsky II, Strauch S, Tyson R, Ungaro M, Venturelli L, Voskanyan H, Vossen A, Voutier E, Watts DP, Wei K, Wei X, Wishart R, Wood MH, Yale B, Yurov M, Zhang J, and Zhao ZW

Abstract

Strange matter is believed to exist in the cores of neutron stars based on simple kinematics. If this is true, then hyperon-nucleon interactions will play a significant part in the neutron star equation of state. Yet, compared to other elastic scattering processes, there is very little data on Λ-N scattering. This experiment utilized the CEBAF Large Acceptance Spectrometer (CLAS) detector to study the Λp→Λp elastic scattering cross section in the incident Λ momentum range 0.9-2.0  GeV/c. These are the first data on this reaction since the 1970s. The new cross sections have significantly better accuracy and precision than the existing world data, and the techniques developed here can also be used in future experiments.

Published
2021
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48. Photoproduction of the f&#95;{2}(1270) Meson Using the CLAS Detector.

Author

Carver M, Celentano A, Hicks K, Marsicano L, Mathieu V, Pilloni A, Adhikari KP, Adhikari S, Amaryan MJ, Angelini G, Atac H, Baltzell NA, Barion L, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biselli AS, Bondi M, Bossù F, Boiarinov S, Briscoe WJ, Brooks WK, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Chatagnon P, Chetry T, Ciullo G, Clark L, Clary BA, Cole PL, Contalbrigo M, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Diehl S, Djalali C, Dugger M, Dupre R, Egiyan H, Ehrhart M, Alaoui AE, Fassi LE, Eugenio P, Fedotov G, Fegan S, Filippi A, Gavalian G, Gevorgyan N, Gilfoyle GP, Girod FX, Gothe RW, Griffioen KA, Hafidi K, Hakobyan H, Hattawy M, Hayward TB, Heddle D, Holtrop M, Huang Q, Hyde CE, Ilieva Y, Ireland DG, Isupov EL, Jenkins D, Jo HS, Joo K, Joosten S, Keller D, Khanal A, Khandaker M, Kim A, Kim CW, Klein FJ, Kripko A, Kubarovsky V, Lanza L, Leali M, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Mascagna V, McCracken ME, McKinnon B, Meziani ZE, Mokeev V, Movsisyan A, Munevar E, Camacho CM, Nadel-Turonski P, Neupane K, Niccolai S, Niculescu G, Osipenko M, Ostrovidov AI, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Phelps W, Pogorelko O, Prok Y, Protopopescu D, Ripani M, Ritchie BG, Ritman J, Rizzo A, Rosner G, Rowley J, Sabatié F, Salgado C, Schmidt A, Schumacher RA, Sharabian YG, Shrestha U, Sokhan D, Soto O, Sparveris N, Stepanyan S, Strakovsky II, Strauch S, Tyler N, Tyson R, Ungaro M, Venturelli L, Voskanyan H, Voutier E, Watts DP, Wei K, Wei X, Yale B, Zachariou N, Zhang J, and Zhao ZW

Abstract

The quark structure of the f&#95;{2}(1270) meson has, for many years, been assumed to be a pure quark-antiquark (qq[over ¯]) resonance with quantum numbers J^{PC}=2^{++}. Recently, it was proposed that the f&#95;{2}(1270) is a molecular state made from the attractive interaction of two ρ mesons. Such a state would be expected to decay strongly to final states with charged pions due to the dominant decay ρ→π^{+}π^{-}, whereas decay to two neutral pions would likely be suppressed. Here, we measure for the first time the reaction γp→π^{0}π^{0}p, using the CEBAF Large Acceptance Spectrometer detector at Jefferson Lab for incident beam energies between 3.6 and 5.4 GeV. Differential cross sections, dσ/dt, for f&#95;{2}(1270) photoproduction are extracted with good precision due to low backgrounds and are compared to theoretical calculations.

Published
2021
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49. Extraction of Beam-Spin Asymmetries from the Hard Exclusive π^{+} Channel off Protons in a Wide Range of Kinematics.

Author

Diehl S, Joo K, Kim A, Avakian H, Kroll P, Park K, Riser D, Semenov-Tian-Shansky K, Tezgin K, Adhikari KP, Adhikari S, Amaryan MJ, Angelini G, Asryan G, Atac H, Barion L, Battaglieri M, Bedlinskiy I, Benmokhtar F, Bianconi A, Biselli AS, Bossù F, Boiarinov S, Briscoe WJ, Brooks WK, Bulumulla D, Burkert VD, Carman DS, Carvajal JC, Celentano A, Chatagnon P, Chetry T, Ciullo G, Clark L, Cole PL, Contalbrigo M, Crede V, D'Angelo A, Dashyan N, De Vita R, Defurne M, Deur A, Dilks C, Djalali C, Dupre R, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Eugenio P, Filippi A, Forest TA, Ghandilyan Y, Gilfoyle GP, Giovanetti KL, Girod FX, Glazier DI, Golovatch E, Gothe RW, Griffioen KA, Guidal M, Guo L, Hakobyan H, Harrison N, Hattawy M, Hayward TB, Heddle D, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Jenkins D, Jo HS, Joosten S, Keller D, Khachatryan M, Khanal A, Khandaker M, Kim CW, Kim W, Kubarovsky V, Kuhn SE, Lanza L, Leali M, Lenisa P, Livingston K, MacGregor IJD, Marchand D, Markov N, Marsicano L, Mascagna V, McKinnon B, Meziani ZE, Mineeva T, Mirazita M, Mokeev V, Munoz Camacho C, Nadel-Turonski P, Niculescu G, Osipenko M, Paolone M, Pappalardo LL, Pasyuk E, Phelps W, Pogorelko O, Price JW, Prok Y, Raue BA, Ripani M, Rizzo A, Rossi P, Rowley J, Sabatié F, Salgado C, Schmidt A, Schumacher RA, Sharabian YG, Shrestha U, Soto O, Sparveris N, Stepanyan S, Stoler P, Strakovsky II, Strauch S, Tan JA, Tyler N, Ungaro M, Venturelli L, Voskanyan H, Voutier E, Watts DP, Wei X, Wood MH, Zachariou N, Zhang J, and Zhao ZW

Abstract

We have measured beam-spin asymmetries to extract the sinϕ moment A&#95;{LU}^{sinϕ} from the hard exclusive e[over →]p→e^{'}nπ^{+} reaction above the resonance region, for the first time with nearly full coverage from forward to backward angles in the center of mass. The A&#95;{LU}^{sinϕ} moment has been measured up to 6.6  GeV^{2} in -t, covering the kinematic regimes of generalized parton distributions (GPD) and baryon-to-meson transition distribution amplitudes (TDA) at the same time. The experimental results in very forward kinematics demonstrate the sensitivity to chiral-odd and chiral-even GPDs. In very backward kinematics where the TDA framework is applicable, we found A&#95;{LU}^{sinϕ} to be negative, while a sign change was observed near 90° in the center of mass. The unique results presented in this Letter will provide critical constraints to establish reaction mechanisms that can help to further develop the GPD and TDA frameworks.

Published
2020
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50. First Measurements of the Double-Polarization Observables F, P, and H in ω Photoproduction off Transversely Polarized Protons in the N^{*} Resonance Region.

Author

Roy P, Park S, Crede V, Anisovich AV, Klempt E, Nikonov VA, Sarantsev AV, Wei NC, Huang F, Nakayama K, Adhikari KP, Adhikari S, Angelini G, Avakian H, Barion L, Battaglieri M, Bedlinskiy I, Biselli AS, Boiarinov S, Briscoe WJ, Brock J, Brooks WK, Burkert VD, Cao F, Carlin C, Carman DS, Celentano A, Chatagnon P, Chetry T, Ciullo G, Cole PL, Contalbrigo M, Cortes O, D'Angelo A, Dashyan N, De Vita R, De Sanctis E, Deur A, Diehl S, Djalali C, Dugger M, Dupre R, Duran B, Egiyan H, Ehrhart M, El Alaoui A, El Fassi L, Eugenio P, Fegan S, Filippi A, Fradi A, Gilfoyle GP, Girod FX, Golovatch E, Gothe RW, Griffioen KA, Guidal M, Guo L, Hafidi K, Hanretty C, Harrison N, Hattawy M, Hayward TB, Heddle D, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Jenkins D, Jo HS, Johnston S, Joosten S, Kabir ML, Keith CD, Keller D, Khachatryan G, Khachatryan M, Khanal A, Khandaker M, Kim A, Kim W, Klein FJ, Kubarovsky V, Kuleshov SV, Kunkel MC, Lanza L, Lenisa P, Livingston K, MacGregor IJD, Marchand D, McKinnon B, Meekins DG, Meyer CA, Mineeva T, Mokeev V, Montgomery RA, Movsisyan A, Munoz Camacho C, Nadel-Turonski P, Niccolai S, Niculescu G, Osipenko M, Ostrovidov AI, Paolone M, Pappalardo LL, Paremuzyan R, Pasyuk E, Payette D, Phelps W, Pierce J, Pogorelko O, Prok Y, Protopopescu D, Raue BA, Ripani M, Riser D, Ritchie BG, Rizzo A, Rosner G, Sabatié F, Salgado C, Schumacher RA, Seely ML, Sharabian YG, Shrestha U, Skorodumina I, Sokhan D, Soto O, Sparveris N, Strakovsky II, Strauch S, Taiuti M, Tan JA, Torayev B, Tyler N, Ungaro M, Voskanyan H, Voutier E, Walford NK, Wang R, Watts DP, Wei X, Wood MH, Zachariou N, Zhang J, and Zhao ZW

Abstract

First measurements of double-polarization observables in ω photoproduction off the proton are presented using transverse target polarization and data from the CEBAF Large Acceptance Spectrometer (CLAS) FROST experiment at Jefferson Lab. The beam-target asymmetry F has been measured using circularly polarized, tagged photons in the energy range 1200-2700 MeV, and the beam-target asymmetries H and P have been measured using linearly polarized, tagged photons in the energy range 1200-2000 MeV. These measurements significantly increase the database on polarization observables. The results are included in two partial-wave analyses and reveal significant contributions from several nucleon (N^{*}) resonances. In particular, contributions from new N^{*} resonances listed in the Review of Particle Properties are observed, which aid in reaching the goal of mapping out the nucleon resonance spectrum.

Published
2019
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