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47 results on '"Meyer CA"'

1. The ep --e'p eta reaction at and above the S11(1535) baryon resonance

Author: Thompson, R., Dytman, S., Kim, Ky, Mueller, J., Adams, Gs, Amaryan, Mj, Anciant, E., Anghinolfi, M., Asavapibhop, B., Auger, T., Audit, G., Avakian, H., Barrow, S., Battaglieri, M., Beard, K., Bektasoglu, M., Bertozzi, W., Bianchi, N., Biselli, A., Boiarinov, S., Bonner, Be, Briscoe, Wj, Brooks, W., Burkert, Vd, Calarco, Jr, Capitani, G., Carman, Ds, Carnahan, B., Cole, Pl, Coleman, A., Connelly, J., Cords, D., Corvisiero, P., Crabb, D., Crannell, H., Cummings, J., Day, D., Degtyarenko, Pv, Demirchyan, Ra, Dennis, Lc, Airton Deppman, Sanctis, E., Vita, R., Dhuga, Ks, Djalali, C., Dodge, Ge, Doughty, D., Dragovitsch, P., Dugger, M., Eckhause, M., Efremenko, Yv, Egiyan, H., Egiyan, Ks, Elouadrhiri, L., Farhi, L., Feuerbach, Rj, Ficenec, J., Fissum, K., Freyberger, A., Funsten, H., Gai, M., Gavrilov, Vb, Gilfoyle, Gp, Giovanetti, K., Gilad, S., Girard, P., Griffioen, Ka, Guidal, M., Guillo, M., Gyurjyan, V., Hancock, D., Hardie, J., Heddle, D., Heisenberg, J., Hersman, Fw, Hicks, K., Hicks, Rs, Holtrop, M., Hyde-Wright, Ce, Ito, Mm, Jenkins, D., Kane, J., Khandaker, M., Kim, W., Klein, A., Klein, Fj, Klusman, M., Kossov, M., Kuhn, Se, Kuang, Y., Laget, Jm, Lawrence, D., Leskin, Ga, Longhi, A., Loukachine, K., Lucas, M., Magahiz, R., Major, Rw, Manak, Jj, Marchand, C., Matthews, Sk, Mcaleer, S., Mccarthy, J., Mcnabb, Jwc, Mecking, Ba, Mestayer, Md, Meyer, Ca, Minehart, R., Mirazita, M., Miskimen, R., Muccifora, V., Mutchler, Gs, Napolitano, J., Niyazov, Ra, Ohandjanyan, Ms, O Brien, Jt, Opper, A., Patois, Y., Peterson, Ga, Philips, S., Pivnyuk, N., Pocanic, D., Pogorelko, O., Polli, E., Preedom, Bm, Price, Jw, Qin, Lm, Raue, Ba, Reolon, Ar, Riccardi, G., Ricco, G., Ripani, M., Ritchie, Bg, Ronchetti, F., Rossi, P., Roudot, E., Rowntree, D., Rubin, Pd, Salgado, Cw, Sanzone, M., Sapunenko, V., Sarty, A., Sargsyan, M., Schumacher, Ra, Shafi, A., Sharabian, Yg, Shaw, J., Shuvalov, Sm, Skabelin, A., Smith, T., Smith, C., Smith, Es, Sober, Di, Spraker, M., Stepanyan, S., Stoler, P., Taiuti, M., Taylor, S., Tedeschi, D., Tung, Ty, Vineyard, Mf, Vlassov, A., Weller, H., Weinstein, Lb, Welsh, R., Weygand, Dp, Whisnant, S., Witkowski, M., Wolin, E., Yegneswaran, A., Yun, J., Zhou, Z., Zhao, J., and Clas, Collaboration
Abstract: New cross sections for the reaction e p--e p eta are reported for total center of mass energy W = 1.5--1.86 GeV and invariant momentum transfer Q2 = 0.25--1.5 (GeV/c)(2). This large kinematic range allows extraction of important new information about response functions, photocouplings, and eta N coupling strengths of baryon resonances. Newly observed structure at W approximately 1.65 GeV is shown to come from interference between S and P waves and can be interpreted with known resonances. Improved values are derived for the photon coupling amplitude for the S11(1535) resonance.
Published: 2000

2. First Measurement of Near-Threshold J/ψ Exclusive Photoproduction off the Proton.

Author: Ali A, Amaryan M, Anassontzis EG, Austregesilo A, Baalouch M, Barbosa F, Barlow J, Barnes A, Barriga E, Beattie TD, Berdnikov VV, Black T, Boeglin W, Boer M, Briscoe WJ, Britton T, Brooks WK, Cannon BE, Cao N, Chudakov E, Cole S, Cortes O, Crede V, Dalton MM, Daniels T, Deur A, Dobbs S, Dolgolenko A, Dotel R, Dugger M, Dzhygadlo R, Egiyan H, Ernst A, Eugenio P, Fanelli C, Fegan S, Foda AM, Foote J, Frye J, Furletov S, Gan L, Gasparian A, Gauzshtein V, Gevorgyan N, Gleason C, Goetzen K, Goncalves A, Goryachev VS, Guo L, Hakobyan H, Hamdi A, Han S, Hardin J, Huber GM, Hurley A, Ireland DG, Ito MM, Jarvis NS, Jones RT, Kakoyan V, Kalicy G, Kamel M, Kourkoumelis C, Kuleshov S, Kuznetsov I, Larin I, Lawrence D, Lersch DI, Li H, Li W, Liu B, Livingston K, Lolos GJ, Lyubovitskij V, Mack D, Marukyan H, Matveev V, McCaughan M, McCracken M, McGinley W, McIntyre J, Meyer CA, Miskimen R, Mitchell RE, Mokaya F, Nerling F, Ng L, Ostrovidov AI, Papandreou Z, Patsyuk M, Pauli P, Pedroni R, Pentchev L, Peters KJ, Phelps W, Pooser E, Qin N, Reinhold J, Ritchie BG, Robison L, Romanov D, Romero C, Salgado C, Schertz AM, Schumacher RA, Schwiening J, Seth KK, Shen X, Shepherd MR, Smith ES, Sober DI, Somov A, Somov S, Soto O, Stevens JR, Strakovsky II, Suresh K, Tarasov V, Taylor S, Teymurazyan A, Thiel A, Vasileiadis G, Werthmüller D, Whitlatch T, Wickramaarachchi N, Williams M, Xiao T, Yang Y, Zarling J, Zhang Z, Zhao G, Zhou Q, Zhou X, and Zihlmann B
Abstract: We report on the measurement of the γp→J/ψp cross section from E_{γ}=11.8 GeV down to the threshold at 8.2 GeV using a tagged photon beam with the GlueX experiment. We find that the total cross section falls toward the threshold less steeply than expected from two-gluon exchange models. The differential cross section dσ/dt has an exponential slope of 1.67±0.39 GeV^{-2} at 10.7 GeV average energy. The LHCb pentaquark candidates P_{c}^{+} can be produced in the s channel of this reaction. We see no evidence for them and set model-dependent upper limits on their branching fractions B(P_{c}^{+}→J/ψp) and cross sections σ(γp→P_{c}^{+})×B(P_{c}^{+}→J/ψp).
Published: 2019
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3. 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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4. Center of Mass Motion of Short-Range Correlated Nucleon Pairs studied via the A(e,e^{'}pp) Reaction.

Author: Cohen EO, Hen O, Piasetzky E, Weinstein LB, Duer M, Schmidt A, Korover I, Hakobyan H, Adhikari S, Akbar Z, Amaryan MJ, Avakian H, Ball J, Barion L, Battaglieri M, Beck A, Bedlinskiy I, Biselli AS, Boiarinov S, Briscoe W, Burkert VD, Cao F, Carman DS, Celentano A, Charles G, Chatagnon P, Chetry T, Ciullo G, Clary BA, Contalbrigo M, Crede V, Cruz Torres R, D'Angelo A, Dashyan N, De Vita R, De Sanctis E, Defurne M, Deur A, Diehl S, Djalali C, Duer M, Dupre R, Egiyan H, Ehrhart M, El Alaoui A, Fassi LE, Eugenio P, Fedotov G, Fersch R, Filippi A, Ghandilyan Y, Giovanetti KL, Girod FX, Golovatch E, Gothe RW, Griffioen KA, Hafidi K, Harrison N, Hauenstein F, Heddle D, Hicks K, Holtrop M, Ireland DG, Ishkhanov BS, Isupov EL, Jenkins D, Jo HS, Johnston S, Kabir ML, Keller D, Khachatryan G, Khachatryan M, Khandaker M, Kim A, Kim W, Klein A, Klein FJ, Korover I, Kubarovsky V, Kuhn SE, Lanza L, Lenisa P, Livingston K, MacGregor IJD, Marchand D, McKinnon B, Mey-Tal Beck S, Meyer CA, Mirazita M, Mokeev V, Montgomery RA, Movsisyan A, Munoz Camacho C, Mustapha B, Nadel-Turonski P, Niccolai S, Niculescu G, Osipenko M, Ostrovidov AI, Paolone M, Paremuzyan R, Pasyuk E, Pogorelko O, Price JW, Prok Y, Protopopescu D, Ripani M, Riser D, Rizzo A, Rosner G, Rossi P, Sabatié F, Schmookler BA, Schumacher RA, Sharabian YG, Sokhan D, Sparveris N, Stepanyan S, Strauch S, Taiuti M, Tan JA, Ungaro M, Voskanyan H, Voutier E, Wang R, Watts DP, Wei X, Wood MH, Zachariou N, Zhang J, Zheng X, and Zhao ZW
Abstract: Short-range correlated (SRC) nucleon pairs are a vital part of the nucleus, accounting for almost all nucleons with momentum greater than the Fermi momentum (k_{F}). A fundamental characteristic of SRC pairs is having large relative momenta as compared to k_{F}, and smaller center of mass (c.m.) which indicates a small separation distance between the nucleons in the pair. Determining the c.m. momentum distribution of SRC pairs is essential for understanding their formation process. We report here on the extraction of the c.m. motion of proton-proton (pp) SRC pairs in carbon and, for the first time in heavier and ansymetric nuclei: aluminum, iron, and lead, from measurements of the A(e,e^{'}pp) reaction. We find that the pair c.m. motion for these nuclei can be described by a three-dimensional Gaussian with a narrow width ranging from 140 to 170 MeV/c, approximately consistent with the sum of two mean-field nucleon momenta. Comparison with calculations appears to show that the SRC pairs are formed from mean-field nucleons in specific quantum states.
Published: 2018
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5. Measurement of the Q^{2} Dependence of the Deuteron Spin Structure Function g_{1} and its Moments at Low Q^{2} with CLAS.

Author: Adhikari KP, Deur A, El Fassi L, Kang H, Kuhn SE, Ripani M, Slifer K, Zheng X, Adhikari S, Akbar Z, Amaryan MJ, Avakian H, Ball J, Balossino I, Barion L, Battaglieri M, Bedlinskiy I, Biselli AS, Bosted P, Briscoe WJ, Brock J, Bültmann S, Burkert VD, Thanh Cao F, Carlin C, Carman DS, Celentano A, Charles G, Chen JP, Chetry T, Choi S, Ciullo G, Clark L, Cole PL, Contalbrigo M, Crede V, D'Angelo A, Dashyan N, De Vita R, De Sanctis E, Defurne M, Djalali C, Dodge GE, Drozdov V, Dupre R, Egiyan H, El Alaoui A, Elouadrhiri L, Eugenio P, Fedotov G, Filippi A, Ghandilyan Y, Gilfoyle GP, Golovatch E, Gothe RW, Griffioen KA, Guidal M, Guler N, Guo L, Hafidi K, Hakobyan H, Hanretty C, Harrison N, Hattawy M, Heddle D, Hicks K, Holtrop M, Hyde CE, Ilieva Y, Ireland DG, Isupov EL, Jenkins D, Jo HS, Johnston SC, Joo K, Joosten S, Kabir ML, Keith CD, Keller D, Khachatryan G, Khachatryan M, Khandaker M, Kim W, Klein A, Klein FJ, Konczykowski P, Kovacs K, Kubarovsky V, Lanza L, Lenisa P, Livingston K, Long E, MacGregor IJD, Markov N, Mayer M, McKinnon B, Meekins DG, Meyer CA, Mineeva T, Mirazita M, Mokeev V, Movsisyan A, Munoz Camacho C, Nadel-Turonski P, Niculescu G, Niccolai S, Osipenko M, Ostrovidov AI, Paolone M, Pappalardo L, Paremuzyan R, Park K, Pasyuk E, Payette D, Phelps W, Phillips SK, Pierce J, Pogorelko O, Poudel J, Price JW, Prok Y, Protopopescu D, Raue BA, Rizzo A, Rosner G, Rossi P, Sabatié F, Salgado C, Schumacher RA, Sharabian YG, Shigeyuki T, Simonyan A, Skorodumina I, Smith GD, Sparveris N, Sokhan D, Stepanyan S, Strakovsky II, Strauch S, Sulkosky V, Taiuti M, Tan JA, Ungaro M, Voutier E, Wei X, Weinstein LB, Zhang J, and Zhao ZW
Abstract: We measured the g_{1} spin structure function of the deuteron at low Q^{2}, 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 Γ_{1}^{d} and the spin polarizability γ_{0}^{d} are precisely determined down to a minimum Q^{2} of 0.02 GeV^{2} 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.
Published: 2018
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6. First Exclusive Measurement of Deeply Virtual Compton Scattering off ^{4}He: Toward the 3D Tomography of Nuclei.

Author: Hattawy M, Baltzell NA, Dupré R, Hafidi K, Stepanyan S, Bültmann S, De Vita R, El Alaoui A, El Fassi L, Egiyan H, Girod FX, Guidal M, Jenkins D, Liuti S, Perrin Y, Torayev B, Voutier E, Adhikari KP, Adhikari S, Adikaram D, Akbar Z, Amaryan MJ, Anefalos Pereira S, Armstrong WR, Avakian H, Ball J, Bashkanov M, Battaglieri M, Batourine V, Bedlinskiy I, Biselli AS, Boiarinov S, Briscoe WJ, Brooks WK, Burkert VD, Thanh Cao F, Carman DS, Celentano A, Charles G, Chetry T, Ciullo G, Clark L, Colaneri L, Cole PL, Contalbrigo M, Cortes O, Crede V, D'Angelo A, Dashyan N, De Sanctis E, Deur A, Djalali C, Elouadrhiri L, Eugenio P, Fedotov G, Fegan S, Fersch R, Filippi A, Fleming JA, Forest TA, Fradi A, Garçon M, Gevorgyan N, Ghandilyan Y, Gilfoyle GP, Giovanetti KL, Gleason C, Gohn W, Golovatch E, Gothe RW, Griffioen KA, Guo L, Hakobyan H, Hanretty C, Harrison N, Heddle D, Hicks K, Holtrop M, Hughes SM, Ireland DG, Ishkhanov BS, Isupov EL, Jiang H, Joo K, Joosten S, Keller D, Khachatryan G, Khachatryan M, Khandaker M, Kim A, Kim W, Klein A, Klein FJ, Kubarovsky V, Kuhn SE, Kuleshov SV, Lanza L, Lenisa P, Livingston K, Lu HY, MacGregor IJD, Markov N, Mayer M, McCracken ME, McKinnon B, Meyer CA, Meziani ZE, Mineeva T, Mirazita M, Mokeev V, Montgomery RA, Moutarde H, Movsisyan A, Munoz Camacho C, Nadel-Turonski P, Net LA, Niccolai S, Niculescu G, Niculescu I, Osipenko M, Ostrovidov AI, Paolone M, Paremuzyan R, Park K, Pasyuk E, Phelps E, Phelps W, Pisano S, Pogorelko O, Price JW, Prok Y, Protopopescu D, Ripani M, Ritchie BG, Rizzo A, Rosner G, Rossi P, Sabatié F, Salgado C, Schumacher RA, Seder E, Sharabian YG, Simonyan A, Skorodumina I, Smith GD, Sokhan D, Sparveris N, Strauch S, Taiuti M, Ungaro M, Voskanyan H, Walford NK, Watts DP, Wei X, Weinstein LB, Wood MH, Zachariou N, Zana L, Zhang J, and Zhao ZW
Abstract: We report on the first measurement of the beam-spin asymmetry in the exclusive process of coherent deeply virtual Compton scattering off a nucleus. The experiment uses the 6 GeV electron beam from the Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab incident on a pressurized ^{4}He gaseous target placed in front of the CEBAF Large Acceptance Spectrometer (CLAS). The scattered electron is detected by CLAS and the photon by a dedicated electromagnetic calorimeter at forward angles. To ensure the exclusivity of the process, a specially designed radial time projection chamber is used to detect the recoiling ^{4}He nuclei. We measure beam-spin asymmetries larger than those observed on the free proton in the same kinematic domain. From these, we are able to extract, in a model-independent way, the real and imaginary parts of the only ^{4}He Compton form factor, H_{A}. This first measurement of coherent deeply virtual Compton scattering on the ^{4}He nucleus, with a fully exclusive final state via nuclear recoil tagging, leads the way toward 3D imaging of the partonic structure of nuclei.
Published: 2017
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7. Towards a resolution of the proton form factor problem: new electron and positron scattering data.

Author: Adikaram D, Rimal D, Weinstein LB, Raue B, Khetarpal P, Bennett RP, Arrington J, Brooks WK, Adhikari KP, Afanasev AV, Amaryan MJ, Anderson MD, Anefalos Pereira S, Avakian H, Ball J, Battaglieri M, Bedlinskiy I, Biselli AS, Bono J, Boiarinov S, Briscoe WJ, Burkert VD, Carman DS, Careccia S, Celentano A, Chandavar S, Charles G, Colaneri L, Cole PL, Contalbrigo M, Crede V, D'Angelo A, Dashyan N, De Vita R, De Sanctis E, Deur A, Djalali C, Dodge GE, Dupre R, Egiyan H, El Alaoui A, El Fassi L, Elouadrhiri L, Eugenio P, Fedotov G, Fegan S, Filippi A, Fleming JA, Fradi A, Garillon B, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gohn W, Golovatch E, Gothe RW, Griffioen KA, Guegan B, Guidal M, Guo L, Hafidi K, Hakobyan H, Hanretty C, Harrison N, Hattawy M, Hicks K, Holtrop M, Hughes SM, Hyde CE, Ilieva Y, Ireland DG, Ishkhanov BS, Jenkins D, Jiang H, Jo HS, Joo K, Joosten S, Kalantarians N, Keller D, Khandaker M, Kim A, Kim W, Klein A, Klein FJ, Koirala S, Kubarovsky V, Kuhn SE, Livingston K, Lu HY, MacGregor IJ, Markov N, Mattione P, Mayer M, McKinnon B, Mestayer MD, Meyer CA, Mirazita M, Mokeev V, Montgomery RA, Moody CI, Moutarde H, Movsisyan A, Camacho CM, Nadel-Turonski P, Niccolai S, Niculescu G, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Peña C, Pisano S, Pogorelko O, Price JW, Procureur S, Prok Y, Protopopescu D, Puckett AJ, Ripani M, Rizzo A, Rosner G, Rossi P, Roy P, Sabatié F, Salgado C, Schott D, Schumacher RA, Seder E, Sharabian YG, Simonyan A, Skorodumina I, Smith ES, Smith GD, Sober DI, Sokhan D, Sparveris N, Stepanyan S, Stoler P, Strauch S, Sytnik V, Taiuti M, Tian Y, Trivedi A, Ungaro M, Voskanyan H, Voutier E, Walford NK, Watts DP, Wei X, Wood MH, Zachariou N, Zana L, Zhang J, Zhao ZW, and Zonta I
Abstract: There is a significant discrepancy between the values of the proton electric form factor, G(E)(p), extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of G(E)(p) 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 (Q(2)) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ϵ at Q(2)=1.45 GeV(2). This measurement is consistent with the size of the form factor discrepancy at Q(2)≈1.75 GeV(2) and with hadronic calculations including nucleon and Δ intermediate states, which have been shown to resolve the discrepancy up to 2-3 GeV(2).
Published: 2015
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8. Strangeness suppression of qq creation observed in exclusive reactions.

Author: Mestayer MD, Park K, Adhikari KP, Aghasyan M, Pereira SA, Ball J, Battaglieri M, Batourine V, Bedlinskiy I, Biselli AS, Boiarinov S, Briscoe WJ, Brooks WK, Burkert VD, Carman DS, Celentano A, Chandavar S, Charles G, Colaneri L, Cole PL, 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 JA, Forest TA, Garillon B, Garçon M, Ghandilyan Y, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Golovatch E, Gothe RW, Griffioen KA, Guegan B, Guidal M, Hakobyan H, Hanretty C, Hattawy M, Holtrop M, Hughes SM, Hyde CE, Ilieva Y, Ireland DG, Jiang H, Jo HS, Joo K, Keller D, Khandaker M, Kim A, Kim W, Koirala S, Kubarovsky V, Kuleshov SV, Lenisa P, Levine WI, Livingston K, Lu HY, MacGregor IJ, Mayer M, McKinnon B, Meyer CA, Mirazita M, Mokeev V, Montgomery RA, Moody CI, Moutarde H, Movsisyan A, Camacho CM, Nadel-Turonski P, Niccolai S, Niculescu G, Niculescu I, Osipenko M, Ostrovidov AI, Pappalardo LL, Paremuzyan R, Peng P, Phelps W, Pisano S, Pogorelko O, Pozdniakov S, Price JW, Protopopescu D, Puckett AJ, Raue BA, Rimal D, Ripani M, Rizzo A, Rosner G, Roy P, Sabatié F, Saini MS, Schott D, Schumacher RA, Simonyan A, Sokhan D, Strauch S, Sytnik V, Tang W, Tian Y, Ungaro M, Vernarsky B, Vlassov AV, Voskanyan H, Voutier E, Walford NK, Watts DP, Wei X, Weinstein LB, Wood MH, Zachariou N, Zhang J, Zhao ZW, and Zonta I
Abstract: We measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ΛK(+), pπ(0), and nπ(+), 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.
Published: 2014
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9. Hard two-body photodisintegration of 3He.

Author: Pomerantz I, Ilieva Y, Gilman R, Higinbotham DW, Piasetzky E, Strauch S, Adhikari KP, Aghasyan M, Allada K, Amaryan MJ, Anefalos Pereira S, Anghinolfi M, Baghdasaryan H, Ball J, Baltzell NA, Battaglieri M, Batourine V, Beck A, Beck S, Bedlinskiy I, Berman BL, Biselli AS, Boeglin W, Bono J, Bookwalter C, Boiarinov S, Briscoe WJ, Brooks WK, Bubis N, Burkert V, Camsonne A, Canan M, Carman DS, Celentano A, Chandavar S, Charles G, Chirapatpimol K, Cisbani E, Cole PL, Contalbrigo M, Crede V, Cusanno F, D'Angelo A, Daniel A, Dashyan N, de Jager CW, De Vita R, De Sanctis E, Deur A, Djalali C, Dodge GE, Doughty D, Dupre R, Dutta C, Egiyan H, El Alaoui A, El Fassi L, Eugenio P, Fedotov G, Fegan S, Fleming JA, Fradi A, Garibaldi F, Geagla O, Gevorgyan N, Giovanetti KL, Girod FX, Glister J, Goetz JT, Gohn W, Golovatch E, Gothe RW, Griffioen KA, Guegan B, Guidal M, Guo L, Hafidi K, Hakobyan H, Harrison N, Heddle D, Hicks K, Ho D, Holtrop M, Hyde CE, Ireland DG, Ishkhanov BS, Isupov EL, Jiang X, Jo HS, Joo K, Katramatou AT, Keller D, Khandaker M, Khetarpal P, Khrosinkova E, Kim A, Kim W, Klein FJ, Koirala S, Kubarovsky A, Kubarovsky V, Kuleshov SV, Kvaltine ND, Lee B, LeRose JJ, Lewis S, Lindgren R, Livingston K, Lu HY, MacGregor IJ, Mao Y, Martinez D, Mayer M, McCullough E, McKinnon B, Meekins D, Meyer CA, Michaels R, Mineeva T, Mirazita M, Moffit B, Mokeev V, Montgomery RA, Moutarde H, Munevar E, Munoz Camacho C, Nadel-Turonski P, Nasseripour R, Nepali CS, Niccolai S, Niculescu G, Niculescu I, Osipenko M, Ostrovidov AI, Pappalardo LL, Paremuzyan R, Park K, Park S, Petratos GG, Phelps E, Pisano S, Pogorelko O, Pozdniakov S, Procureur S, Protopopescu D, Puckett AJ, Qian X, Qiang Y, Ricco G, Rimal D, Ripani M, Ritchie BG, Rodriguez I, Ron G, Rosner G, Rossi P, Sabatié F, Saha A, Saini MS, Sarty AJ, Sawatzky B, Saylor NA, Schott D, Schulte E, Schumacher RA, Seder E, Seraydaryan H, Shneor R, Smith GD, Sokhan D, Sparveris N, Stepanyan SS, Stepanyan S, Stoler P, Subedi R, Sulkosky V, Taiuti M, Tang W, Taylor CE, Tkachenko S, Ungaro M, Vernarsky B, Vineyard MF, Voskanyan H, Voutier E, Walford NK, Wang Y, Watts DP, Weinstein LB, Weygand DP, Wojtsekhowski B, Wood MH, Yan X, Yao H, Zachariou N, Zhan X, Zhang J, Zhao ZW, Zheng X, and Zonta I
Abstract: We have measured cross sections for the γ(3)He → 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.
Published: 2013
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10. Measurement of exclusive π(0) electroproduction structure functions and their relationship to transverse generalized parton distributions.

Author: Bedlinskiy I, Kubarovsky V, Niccolai S, Stoler P, Adhikari KP, Aghasyan M, Amaryan MJ, Anghinolfi M, Avakian H, Baghdasaryan H, Ball J, Baltzell NA, Battaglieri M, Bennett RP, Biselli AS, Bookwalter C, Boiarinov S, Briscoe WJ, Brooks WK, Burkert VD, Carman DS, Celentano A, Chandavar S, Charles G, Contalbrigo M, Crede V, D'Angelo A, Daniel 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 JA, Forest TA, Fradi A, Garçon M, Gevorgyan N, Giovanetti KL, Girod FX, Gohn W, Gothe RW, Graham L, Griffioen KA, Guegan B, Guidal M, Guo L, Hafidi K, Hakobyan H, Hanretty C, Heddle D, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Jo HS, Joo K, Keller D, Khandaker M, Khetarpal P, Kim A, Kim W, Klein FJ, Koirala S, Kubarovsky A, Kuhn SE, Kuleshov SV, Kvaltine ND, Livingston K, Lu HY, MacGregor IJ, Mao Y, Markov N, Martinez D, Mayer M, McKinnon B, Meyer CA, Mineeva T, Mirazita M, Mokeev V, Moutarde H, Munevar E, Munoz Camacho C, Nadel-Turonski P, Niculescu G, Niculescu I, Osipenko M, Ostrovidov AI, Pappalardo LL, Paremuzyan R, Park K, Park S, Pasyuk E, Anefalos Pereira S, Phelps E, Pisano S, Pogorelko O, Pozdniakov S, Price JW, Procureur S, Prok Y, Protopopescu D, Puckett AJ, Raue BA, Ricco G, Rimal D, Ripani M, Rosner G, Rossi P, Sabatié F, Saini MS, Salgado C, Saylor N, Schott D, Schumacher RA, Seder E, Seraydaryan H, Sharabian YG, Smith GD, Sober DI, Sokhan D, Stepanyan SS, Stepanyan S, Strauch S, Taiuti M, Tang W, Taylor CE, Tian Y, Tkachenko S, Ungaro M, Vineyard MF, Vlassov A, Voskanyan H, Voutier E, Walford NK, Watts DP, Weinstein LB, Weygand DP, Wood MH, Zachariou N, Zhang J, Zhao ZW, and Zonta I
Abstract: Exclusive π(0) electroproduction at a beam energy of 5.75 GeV has been measured with the Jefferson Lab CLAS spectrometer. Differential cross sections were measured at more than 1800 kinematic values in Q(2), x(B), t, and ϕ(π), in the Q(2) range from 1.0 to 4.6 GeV(2), -t up to 2 GeV(2), and x(B) from 0.1 to 0.58. Structure functions σ(T)+ϵσ(L), σ(TT), and σ(LT) were extracted as functions of t for each of 17 combinations of Q(2) and x(B). The data were compared directly with two handbag-based calculations including both longitudinal and transversity generalized parton distributions (GPDs). Inclusion of only longitudinal GPDs very strongly underestimates σ(T)+ϵσ(L) and fails to account for σ(TT) and σ(LT), while inclusion of transversity GPDs brings the calculations into substantially better agreement with the data. There is very strong sensitivity to the relative contributions of nucleon helicity-flip and helicity nonflip processes. The results confirm that exclusive π(0) electroproduction offers direct experimental access to the transversity GPDs.
Published: 2012
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11. Measurement of single- and double-spin asymmetries in deep inelastic pion electroproduction with a longitudinally polarized target.

Author: Avakian H, Bosted P, Burkert VD, Elouadrhiri L, Adhikari KP, Aghasyan M, Amaryan M, Anghinolfi M, Baghdasaryan H, Ball J, Battaglieri M, Bedlinskiy I, Biselli AS, Branford D, Briscoe WJ, Brooks W, Carman DS, Casey L, Cole PL, Collins P, Crabb D, 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, Dodge G, Doughty D, Dupre R, El Alaoui A, Eugenio P, Fegan S, Fersch R, Forest TA, Fradi A, Gabrielyan MY, Gavalian G, Gevorgyan N, Gilfoyle GP, Giovanetti KL, Girod FX, Gohn W, Gothe RW, Griffioen KA, Guidal M, Guler N, Guo L, Hafidi K, Hakobyan H, Hanretty C, Hassall N, Heddle D, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Isupov EL, Jawalkar SS, Jo HS, Joo K, Keller D, Khandaker M, Khetarpal P, Kim W, Klein A, Klein FJ, Konczykowski P, Kubarovsky V, Kuhn SE, Kuleshov SV, Kuznetsov V, Livingston K, Lu HY, Markov N, Mayer M, Martinez D, McAndrew J, McCracken ME, McKinnon B, Meyer CA, Mineeva T, Mirazita M, Mokeev V, Moreno B, Moriya K, Morrison B, Moutarde H, Munevar E, Nadel-Turonski P, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niroula MR, Osipenko M, Ostrovidov AI, Paremuzyan R, Park K, Park S, Pasyuk E, Pereira SA, Perrin Y, Pisano S, Pogorelko O, Price JW, Procureur S, Prok Y, Protopopescu D, Raue BA, Ricco G, Ripani M, Rosner G, Rossi P, Sabatié F, Saini MS, Salamanca J, Salgado C, Schumacher RA, Seder E, Seraydaryan H, Sharabian YG, Sober DI, Sokhan D, Stepanyan SS, Stepanyan S, Stoler P, Strauch S, Suleiman R, Taiuti M, Tedeschi DJ, Tkachenko S, Ungaro M, Vernarsky B, Vineyard MF, Voutier E, Watts DP, Weinstein LB, Weygand DP, Wood MH, Zhang J, Zhao B, and Zhao ZW
Abstract: We report the first measurement of the transverse momentum dependence of double-spin asymmetries in semi-inclusive production of pions in deep-inelastic scattering off the longitudinally polarized proton. Data have been obtained using a polarized electron beam of 5.7 GeV with the CLAS detector at the Jefferson Lab (JLab). Modulations of single spin asymmetries over the azimuthal angle between lepton scattering and hadron production planes ϕ have been measured over a wide kinematic range in Bjorken x and virtual photon squared four-momentum Q2. A significant nonzero sin2ϕ single spin asymmetry was observed for the first time indicating strong spin-orbit correlations for transversely polarized quarks in the longitudinally polarized proton.
Published: 2010
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12. Tensor correlations measured in 3He(e,e' pp)n.

Author: Baghdasaryan H, Weinstein LB, Laget JM, Adhikari KP, Aghasyan M, Amarian M, Anghinolfi M, Avakian H, Ball J, Battaglieri M, Bedlinskiy I, Bennett RP, Berman BL, Biselli AS, Bookwalter C, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Carman DS, Crede V, D'Angelo A, Daniel A, Dashyan N, De Vita R, De Sanctis E, Deur A, Dey B, Dickson R, Djalali C, Dodge GE, Doughty D, Dupre R, Egiyan H, El Alaoui A, El Fassi L, Eugenio P, Fegan S, Gabrielyan MY, Gilfoyle GP, Giovanetti KL, Gohn W, Gothe RW, Griffioen KA, Guidal M, Guo L, Gyurjyan V, Hakobyan H, Hanretty C, Hyde CE, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Joo K, Keller D, Khandaker M, Khetarpal P, Kim A, Kim W, Klein A, Klein FJ, Konczykowski P, Kubarovsky V, Kuhn SE, Kuleshov SV, Kuznetsov V, Kvaltine ND, Livingston K, Lu HY, Macgregor IJ, Markov N, Mayer M, McAndrew J, McKinnon B, Meyer CA, Mikhailov K, Mokeev V, Moreno B, Moriya K, Morrison B, Moutarde H, Munevar E, Nadel-Turonski P, Nepali C, Niccolai S, Niculescu G, Niculescu I, Osipenko M, Ostrovidov AI, Paremuzyan R, Park K, Park S, Pasyuk E, Pereira SA, Pisano S, Pogorelko O, Pozdniakov S, Price JW, Procureur S, Protopopescu D, Ricco G, Ripani M, Rosner G, Rossi P, Sabatié F, Salgado C, Schumacher RA, Seraydaryan H, Smith GD, Sober DI, Sokhan D, Stepanyan SS, Stepanyan S, Stoler P, Strauch S, Taiuti M, Tang W, Taylor CE, Tedeschi DJ, Ungaro M, Vineyard MF, Voutier E, Watts DP, Weygand DP, Wood MH, Zhao B, and Zhao ZW
Abstract: We have measured the 3He(e,e' pp)n reaction at an incident energy of 4.7 GeV over a wide kinematic range. We identified spectator correlated pp and pn nucleon pairs by using kinematic cuts and measured their relative and total momentum distributions. This is the first measurement of the ratio of pp to pn pairs as a function of pair total momentum p(tot). For pair relative momenta between 0.3 and 0.5 GeV/c, the ratio is very small at low p(tot) and rises to approximately 0.5 at large p(tot). This shows the dominance of tensor over central correlations at this relative momentum.
Published: 2010
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13. Absorption of the ω and ϕ mesons in nuclei.

Author: Wood MH, Nasseripour R, Paolone M, Djalali C, Weygand DP, Adhikari KP, Anghinolfi M, Ball J, Battaglieri M, Batourine V, Bedlinskiy I, Bellis M, Berman BL, Biselli AS, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Careccia SL, Carman DS, Cole PL, Collins P, Crede V, D'Angelo A, Daniel A, De Vita R, De Sanctis E, Deur A, Dey B, Dhamija S, Dickson R, Doughty D, Dupre R, Egiyan H, El Alaoui A, El Fassi L, Eugenio P, Fegan S, Gabrielyan MY, Garçon M, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gohn W, Gothe RW, Graham L, Guidal M, Guo L, Hafidi K, Hakobyan H, Hanretty C, Hassall N, Hicks K, Holtrop M, Ilieva Y, Ireland DG, Ishkhanov BS, Jawalkar SS, Jo HS, Joo K, Keller D, Khandaker M, Khetarpal P, Kim A, Kim W, Klein A, Klein FJ, Konczykowski P, Kubarovsky V, Kuleshov SV, Kuznetsov V, Livingston K, Martinez D, Mayer M, McAndrew J, McCracken ME, McKinnon B, Meyer CA, Mineeva T, Mirazita M, Mokeev V, Moreno B, Moriya K, Morrison B, Munevar E, Nadel-Turonski P, Ni A, Niccolai S, Niculescu G, Niculescu I, Niroula MR, Osipenko M, Ostrovidov AI, Paremuzyan R, Park K, Park S, Pasyuk E, Anefalos Pereira S, Pisano S, Pogorelko O, Pozdniakov S, Price JW, Procureur S, Prok Y, Protopopescu D, Raue BA, Ricco G, Ripani M, Rosner G, Rossi P, Sabatié F, Saini MS, Salamanca J, Salgado C, Schott D, Schumacher RA, Seder E, Seraydaryan H, Sharabian YG, Smith GD, Sober DI, Sokhan D, Stepanyan S, Stepanyan SS, Stoler P, Strakovsky II, Strauch S, Taiuti M, Tang W, Taylor CE, Tedeschi DJ, Tkachenko S, Ungaro M, Vernarsky B, Vineyard MF, Voutier E, Watts DP, Weinstein LB, Zhang J, Zhao B, and Zhao ZW
Abstract: Because of their long lifetimes, the ω and ϕ mesons are the ideal candidates for the study of possible modifications of the in-medium meson-nucleon interaction through their absorption inside the nucleus. During the E01-112 experiment at the Thomas Jefferson National Accelerator Facility, the mesons were photoproduced from 2H, C, Ti, Fe, and Pb targets. This Letter reports the first measurement of the ratio of nuclear transparencies for the e+e- channel. The ratios indicate larger in-medium widths compared with what have been reported in other reaction channels. The absorption of the ω meson is stronger than that reported by the CBELSA-TAPS experiment and cannot be explained by recent theoretical models.
Published: 2010
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14. Measurement of the differential cross section for the reaction gamman-->pi- p from deuterium.

Author: Chen W, Mibe T, Dutta D, Gao H, Laget JM, Mirazita M, Rossi P, Stepanyan S, Strakovsky II, Amaryan MJ, Anghinolfi M, Bagdasaryan H, Battaglieri M, Bellis M, Berman BL, Biselli AS, Bookwalter C, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Careccia SL, Carman DS, Casey L, Cole PL, Collins P, Crede V, Daniel A, Dashyan N, De Vita R, De Sanctis E, Deur A, Dhamija S, Dickson R, Djalali C, Dodge GE, Doughty D, Egiyan H, Eugenio P, Fedotov G, Fradi A, Garçon M, Gilfoyle GP, Giovanetti KL, Girod FX, Gohn W, Gothe RW, Griffioen KA, Guidal M, Hakobyan H, Hanretty C, Hassall N, Heddle D, Hicks K, Holtrop M, Hyde CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Jo HS, Johnstone JR, Joo K, Keller D, Khandaker M, Khetarpal P, Kim W, Klein A, Klein FJ, Kramer LH, Kubarovsky V, Kuhn SE, Kuleshov SV, Kuznetsov V, Livingston K, Lu HY, Markov N, McCracken ME, McKinnon B, Meyer CA, Mineeva T, Mokeev V, Moreno B, Moriya K, Nadel-Turonski P, Nasseripour R, Niccolai S, Niculescu I, Niroula MR, Osipenko M, Ostrovidov AI, Park K, Park S, Pereira SA, Pogorelko O, Pozdniakov S, Price JW, Procureur S, Protopopescu D, Raue BA, Ricco G, Ripani M, Ritchie BG, Rosner G, Sabatié F, Saini MS, Salamanca J, Salgado C, Schumacher RA, Sharabian YG, Sober DI, Sokhan D, Stepanyan SS, Strauch S, Taiuti M, Tedeschi DJ, Tkachenko S, Ungaro M, Vineyard MF, Watts DP, Weinstein LB, Weygand DP, Wood MH, Yegneswaran A, Zhang J, and Zhao B
Abstract: We report a measurement of the differential cross section for the gamman-->pi- p process from the CLAS detector at Jefferson Laboratory in Hall B for photon energies between 1.0 and 3.5 GeV and pion center-of-mass (c.m.) angles (thetac.m.) between 50 degrees and 115 degrees. We confirm a previous indication of a broad enhancement around a c.m. energy ([sqrt]s) of 2.1 GeV at thetac.m.=90 degrees in the scaled differential cross section s7dsigma/dt and a rapid falloff in a center-of-mass energy region of about 400 MeV following the enhancement. Our data show an angular dependence of this enhancement as the suggested scaling region is approached for thetac.m. from 70 degrees to 105 degrees.
Published: 2009
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15. Precise measurement of the neutron magnetic form factor G(M)n in the few-GeV2 region.

Author: Lachniet J, Afanasev A, Arenhövel H, Brooks WK, Gilfoyle GP, Higinbotham D, Jeschonnek S, Quinn B, Vineyard MF, Adams G, Adhikari KP, Amaryan MJ, Anghinolfi M, Asavapibhop B, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Barrow S, Batourine V, Battaglieri M, Beard K, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Biselli AS, Bonner BE, Bookwalter C, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Bültmann S, Burkert VD, Calarco JR, Careccia SL, Carman DS, Casey L, Cheng L, Cole PL, Coleman A, Collins P, Cords D, Corvisiero P, Crabb D, Crede V, Cummings JP, Dale D, Daniel A, Dashyan N, De Masi R, De Vita R, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dhamija S, Dharmawardane KV, Dhuga KS, Dickson R, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, El Fassi L, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Fedotov G, Fersch R, Feuerbach RJ, Forest TA, Fradi A, Gabrielyan MY, Garçon M, Gavalian G, Gevorgyan N, Giovanetti KL, Girod FX, Goetz JT, Gohn W, Golovatch E, Gothe RW, Graham L, Griffioen KA, Guidal M, Guillo M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan H, Hanretty C, Hardie J, Hassall N, Heddle D, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hu J, Huertas M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Johnstone JR, Joo K, Juengst HG, Kageya T, Kalantarians N, Keller D, Kellie JD, Khandaker M, Khetarpal P, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klusman M, Konczykowski P, Kossov M, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov SV, Kuznetsov V, Laget JM, Langheinrich J, Lawrence D, Lima AC, Livingston K, Lowry M, Lu HY, Lukashin K, Maccormick M, Malace S, Manak JJ, Markov N, Mattione P, McAleer S, McCracken ME, McKinnon B, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Mineeva T, Minehart R, Mirazita M, Miskimen R, Mokeev V, Moreno B, Moriya K, Morrow SA, Moteabbed M, Mueller J, Munevar E, Mutchler GS, Nadel-Turonski P, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, O'Rielly GV, Osipenko M, Ostrovidov AI, Park K, Park S, Pasyuk E, Paterson C, Pereira SA, Philips SA, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Popa I, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Rosner G, Rossi P, Rowntree D, Rubin PD, Sabatié F, Saini MS, Salamanca J, Salgado C, Sandorfi A, Santoro JP, Sapunenko V, Schott D, Schumacher RA, Serov VS, Sharabian YG, Sharov D, Shaw J, Shvedunov NV, Skabelin AV, Smith ES, Smith LC, Sober DI, Sokhan D, Starostin A, Stavinsky A, Stepanyan S, Stepanyan SS, Stokes BE, Stoler P, Stopani KA, Strakovsky II, Strauch S, Suleiman R, Taiuti M, Taylor S, Tedeschi DJ, Thompson R, Tkabladze A, Tkachenko S, Ungaro M, Vlassov AV, Watts DP, Wei X, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Yun J, Yurov M, Zana L, Zhang J, Zhao B, and Zhao ZW
Abstract: The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q;{2}=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.
Published: 2009
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16. Measurement of direct f0(980) photoproduction on the proton.

Author: Battaglieri M, De Vita R, Szczepaniak AP, Adhikari KP, Aghasyan M, Amaryan MJ, Ambrozewicz P, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Batourine V, Bedlinskiy I, Bellis M, Benmouna N, Berman BL, Bibrzycki L, Biselli AS, Bookwalter C, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Calarco JR, Careccia SL, Carman DS, Casey L, Chen S, Cheng L, Clinton E, Cole PL, Collins P, Crabb D, Crannell H, Crede V, Cummings JP, Dale D, Daniel A, Dashyan N, De Masi R, De Sanctis E, Degtyarenko PV, Deur A, Dhamija S, Dharmawardane KV, Dickson R, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dzyubak OP, Egiyan H, Egiyan KS, El Fassi L, Elouadrhiri L, Eugenio P, Fedotov G, Fersch R, Forest TA, Fradi A, Gabrielyan MY, Gan L, Garçon M, Gasparian A, Gavalian G, Gevorgyan N, Gilfoyle GP, Giovanetti KL, Girod FX, Glamazdin O, Goett J, Goetz JT, Gohn W, Golovatch E, Gordon CI, Gothe RW, Graham L, Griffioen KA, Guidal M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan H, Hakobyan RS, Hanretty C, Hardie J, Hassall N, Heddle D, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hyde CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Johnstone JR, Joo K, Juengst HG, Kageya T, Kalantarians N, Keller D, Kellie JD, Khandaker M, Khetarpal P, Kim W, Klein A, Klein FJ, Klimenko AV, Konczykowski P, Kossov M, Krahn Z, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov SV, Kuznetsov V, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Lee T, Lesniak L, Li J, Livingston K, Lowry M, Lu HY, Maccormick M, Malace S, Markov N, Mattione P, McCracken ME, McKinnon B, Mecking BA, Melone JJ, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Mineeva T, Minehart R, Mirazita M, Miskimen R, Mochalov V, Mokeev V, Moreno B, Moriya K, Morrow SA, Moteabbed M, Munevar E, Mutchler GS, Nadel-Turonski P, Nakagawa I, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, Osipenko M, Ostrovidov AI, Park K, Park S, Pasyuk E, Paris M, Paterson C, Pereira SA, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Pozdniakov S, Price JW, Prok Y, Protopopescu D, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Rosner G, Rossi P, Sabatié F, Saini MS, Salamanca J, Salgado C, Sandorfi A, Santoro JP, Sapunenko V, Schott D, Schumacher RA, Serov VS, Sharabian YG, Sharov D, Shvedunov NV, Smith ES, Smith LC, Sober DI, Sokhan D, Starostin A, Stavinsky A, Stepanyan S, Stepanyan SS, Stokes BE, Stoler P, Stopani KA, Strakovsky II, Strauch S, Taiuti M, Tedeschi DJ, Teymurazyan A, Tkabladze A, Tkachenko S, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Watts DP, Wei X, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Yurov M, Zana L, Zhang J, Zhao B, and Zhao ZW
Abstract: We report on the results of the first measurement of exclusive f_{0}(980) meson photoproduction on protons for E_{gamma}=3.0-3.8 GeV and -t=0.4-1.0 GeV2. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. The resonance was detected via its decay in the pi;{+}pi;{-} channel by performing a partial wave analysis of the reaction gammap-->ppi;{+}pi;{-}. Clear evidence of the f_{0}(980) meson was found in the interference between P and S waves at M_{pi;{+}pi;{-}} approximately 1 GeV. The S-wave differential cross section integrated in the mass range of the f_{0}(980) was found to be a factor of about 50 smaller than the cross section for the rho meson. This is the first time the f_{0}(980) meson has been measured in a photoproduction experiment.
Published: 2009
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17. Search for the photoexcitation of exotic mesons in the pi+pi+pi- system.

Author: Nozar M, Salgado C, Weygand DP, Guo L, Adams G, Li J, Eugenio P, Amaryan MJ, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Barrow S, Battaglieri M, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Biselli AS, Blaszczyk L, Bonner BE, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Carnahan B, Casey L, Cazes A, Chen S, Cheng L, Cole PL, Collins P, Coltharp P, Cords D, Corvisiero P, Crabb D, Crannell H, Crede V, Cummings JP, Dale D, Dashyan N, De Masi R, De Vita R, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dharmawardane KV, Dhuga KS, Dickson R, Djalali C, Dodge GE, Doughty D, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, El Fassi L, Elouadrhiri L, Fatemi R, Fedotov G, Feuerbach RJ, Forest TA, Fradi A, Funsten H, Garçon M, Gavalian G, Gevorgyan N, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gothe RW, Griffioen KA, Guidal M, Guillo M, Guler N, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan H, Hanretty C, Hardie J, Hassall N, Heddle D, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Johnstone JR, Joo K, Juengst HG, Kalantarians N, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Kossov M, Krahn Z, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov SV, Kuznetsov V, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Livingston K, Lu HY, Maccormick M, Markov N, Mattione P, McAleer S, McKinnon B, McNabb JW, Mecking BA, Mehrabyan S, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Mirazita M, Miskimen R, Mokeev V, Moreno B, Moriya K, Morrow SA, Moteabbed M, Mueller J, Munevar E, Mutchler GS, Nadel-Turonski P, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, O'Rielly GV, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Anefalos Pereira S, Philips SA, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Popa I, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Rubin PD, Sabatié F, Salamanca J, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Sharov D, Shvedunov NV, Skabelin AV, Smith ES, Smith LC, Sober DI, Sokhan D, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Stoler P, Strakovsky II, Strauch S, Taiuti M, Tedeschi DJ, Thoma U, Tkabladze A, Tkachenko S, Todor L, Ungaro M, Vineyard MF, Vlassov AV, Watts DP, Weinstein LB, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang J, Zhao B, and Zhao ZW
Abstract: A search for exotic mesons in the pi;{+}pi;{+}pi;{-} system photoproduced by the charge exchange reaction gammap-->pi;{+}pi;{+}pi;{-}(n) was carried out by the CLAS Collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target. A partial wave analysis was performed on a sample of 83 000 events, the highest such statistics to date in this reaction at these energies. The main objective of this study was to look for the photoproduction of an exotic J;{PC}=1;{-+} resonant state in the 1 to 2 GeV mass range. Our partial wave analysis shows production of the a_{2}(1320) and the pi_{2}(1670) mesons, but no evidence for the a_{1}(1260), nor the pi_{1}(1600) exotic state at the expected levels. An upper limit of 13.5 nb is determined for the exotic pi_{1}(1600) cross section, less than 2% of the a_{2}(1320) production.
Published: 2009
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18. Measurement of deeply virtual compton scattering beam-spin asymmetries.

Author: Girod FX, Niyazov RA, Avakian H, Ball J, Bedlinskiy I, Burkert VD, De Masi R, Elouadrhiri L, Garçon M, Guidal M, Jo HS, Joo K, Kubarovsky V, Kuleshov SV, MacCormick M, Niccolai S, Pogorelko O, Sabatié F, Stepanyan S, Stoler P, Ungaro M, Zhao B, Amaryan MJ, Ambrozewicz P, Anghinolfi M, Asryan G, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Batourine V, Battaglieri M, Bellis M, Benmouna N, Berman BL, Biselli AS, Blaszczyk L, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Casey L, Chen S, Cheng L, Cole PL, Collins P, Coltharp P, Crabb D, Crede V, Dashyan N, De Sanctis E, De Vita R, Degtyarenko PV, Deur A, Dharmawardane KV, Dickson R, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dzyubak OP, Egiyan H, Egiyan KS, El Fassi L, Eugenio P, Fedotov G, Feldman G, Funsten H, Gavalian G, Gilfoyle GP, Giovanetti KL, Goetz JT, Gonenc A, Gothe RW, Griffioen KA, Guler N, Guo L, Gyurjyan V, Hafidi K, Hakobyan H, Hanretty C, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hyde CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Johnstone JR, Juengst HG, Kalantarians N, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Kossov M, Krahn Z, Kramer LH, Kuhn J, Kuhn SE, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Lee T, Livingston K, Lu HY, Markov N, Mattione P, Mazouz M, McKinnon B, Mecking BA, Mestayer MD, Meyer CA, Mibe T, Michel B, Mikhailov K, Mirazita M, Miskimen R, Mokeev V, Moriya K, Morrow SA, Moteabbed M, Munevar E, Mutchler GS, Nadel-Turonski P, Nasseripour R, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Nozar M, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Anefalos Pereira S, Pierce J, Pivnyuk N, Pocanic D, Pozdniakov S, Price JW, Procureur S, Prok Y, Protopopescu D, Raue BA, Ricco G, Ripani M, Ritchie BG, Rosner G, Rossi P, Salamanca J, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Sharov D, Shvedunov NV, Smith ES, Smith LC, Sober DI, Sokhan D, Stavinsky A, Stepanyan SS, Stokes BE, Strakovsky II, Strauch S, Taiuti M, Tedeschi DJ, Tkabladze A, Tkachenko S, Tur C, Vineyard MF, Vlassov AV, Voutier E, Watts DP, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang J, and Zhao ZW
Abstract: The beam-spin asymmetries in the hard exclusive electroproduction of photons on the proton (e p-->epgamma) were measured over a wide kinematic range and with high statistical accuracy. These asymmetries result from the interference of the Bethe-Heitler process and of deeply virtual Compton scattering. Over the whole kinematic range (x(B) from 0.11 to 0.58, Q2 from 1 to 4.8 GeV2, -t from 0.09 to 1.8 GeV2), the azimuthal dependence of the asymmetries is compatible with expectations from leading-twist dominance, A approximately a sinphi/(1+c cosphi). This extensive set of data can thus be used to constrain significantly the generalized parton distributions of the nucleon in the valence quark sector.
Published: 2008
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19. Bayesian analysis of pentaquark signals from CLAS data.

Author: Ireland DG, McKinnon B, Protopopescu D, Ambrozewicz P, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Batourine V, Battaglieri M, Bedlinskiy I, Bellis M, Benmouna N, Berman BL, Biselli AS, Blaszczyk L, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Casey L, Chen S, Cheng L, Cole PL, Collins P, Coltharp P, Crabb D, Crede V, Dashyan N, De Masi R, De Vita R, De Sanctis E, Degtyarenko PV, Deur A, Dickson R, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dzyubak OP, Egiyan KS, El Fassi L, Elouadrhiri L, Eugenio P, Fedotov G, Feldman G, Fradi A, Funsten H, Garçon M, Gavalian G, Gevorgyan N, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gohn W, Gonenc A, Gothe RW, Griffioen KA, Guidal M, Guler N, Guo L, Gyurjyan V, Hafidi K, Hakobyan H, Hanretty C, Hassall N, Hersman FW, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ishkhanov BS, Isupov EL, Jenkins D, Jo HS, Johnstone JR, Joo K, Juengst HG, Kalantarians N, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Kossov M, Krahn Z, Kramer LH, Kubarovsky V, Kuhn J, Kuleshov SV, Kuznetsov V, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Livingston K, Lu HY, Maccormick M, Markov N, Mattione P, Mecking BA, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Mirazita M, Miskimen R, Mokeev V, Moreno B, Moriya K, Morrow SA, Moteabbed M, Munevar E, Mutchler GS, Nadel-Turonski P, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Pereira SA, Pierce J, Pivnyuk N, Pogorelko O, Pozdniakov S, Price JW, Procureur S, Prok Y, Raue BA, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Sabatié F, Salamanca J, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Sharov D, Shvedunov NV, Smith LC, Sober DI, Sokhan D, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Stoler P, Strauch S, Taiuti M, Tedeschi DJ, Tkabladze A, Tkachenko S, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Watts DP, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang J, Zhao B, and Zhao ZW
Abstract: We examine the results of two measurements by the CLAS collaboration, one of which claimed evidence for a Theta(+) pentaquark, while the other found no such evidence. The unique feature of these two experiments was that they were performed with the same experimental setup. Using a Bayesian analysis, we find that the results of the two experiments are in fact compatible with each other, but that the first measurement did not contain sufficient information to determine unambiguously the existence of a Theta(+). Further, we suggest a means by which the existence of a new candidate particle can be tested in a rigorous manner.
Published: 2008
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20. Search for medium modifications of the rho meson.

Author: Nasseripour R, Wood MH, Djalali C, Weygand DP, Tur C, Mosel U, Muehlich P, Adams G, Amaryan MJ, Ambrozewicz P, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Barrow S, Battaglieri M, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Biselli AS, Blaszczyk L, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Carnahan B, Casey L, Chen S, Cole PL, Collins P, Coltharp P, Crabb D, Crannell H, Crede V, Cummings JP, Dashyan N, De Masi R, De Vita R, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dharmawardane KV, Dickson R, Dodge GE, Doughty D, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, El Fassi L, Elouadrhiri L, Eugenio P, Fedotov G, Feldman G, Feuerbach RJ, Funsten H, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gordon CI, Gothe RW, Griffioen KA, Guidal M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan H, Hakobyan RS, Hanretty C, Hardie J, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Johnstone JR, Joo K, Juengst HG, Kalantarians N, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Kossov M, Krahn Z, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov SV, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Li J, Livingston K, Lu HY, Maccormick M, Markov N, Mattione P, McAleer S, McKinnon B, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Moriya K, Morrow SA, Moteabbed M, Mueller J, Munevar E, Mutchler GS, Nadel-Turonski P, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Anefalos Pereira S, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Sabatié F, Salamanca J, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Sharov D, Shvedunov NV, Smith ES, Smith LC, Sober DI, Sokhan D, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Stoler P, Strakovsky II, Strauch S, Taiuti M, Tedeschi DJ, Tkabladze A, Tkachenko S, Todor L, Ungaro M, Vineyard MF, Vlassov AV, Watts DP, Weinstein LB, Williams M, Wolin E, Yegneswaran A, Zana L, Zhang B, Zhang J, Zhao B, and Zhao ZW
Abstract: The photoproduction of vector mesons on various nuclei has been studied using the CLAS detector at Jefferson Laboratory. The vector mesons, rho, omega, and varphi, are observed via their decay to e;{+}e;{-}, in order to reduce the effects of final-state interactions in the nucleus. Of particular interest are possible in-medium effects on the properties of the rho meson. The rho mass spectrum is extracted from the data on various nuclei, 2H, C, Fe, and Ti. We observe no significant mass shift and some broadening consistent with expected collisional broadening for the rho meson.
Published: 2007
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21. Experimental study of exclusive 2H(e,e'p)n reaction mechanisms at high Q2.

Author: Egiyan KS, Asryan G, Gevorgyan N, Griffioen KA, Laget JM, Kuhn SE, Adams G, Amaryan MJ, Ambrozewicz P, Anghinolfi M, Audit G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Barrow S, Batourine V, Battaglieri M, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Biselli AS, Blaszczyk L, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Cazes A, Chen S, Cole PL, Collins P, Coltharp P, Cords D, Corvisiero P, Crabb D, Crede V, Cummings JP, Dashyan N, De Masi R, De Vita R, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dharmawardane KV, Dickson R, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dytman S, Dzyubak OP, Egiyan H, El Fassi L, Elouadrhiri L, Eugenio P, Fatemi R, Fedotov G, Feldman G, Feuerbach RJ, Fersch R, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gonenc A, Gordon CI, Gothe RW, Guidal M, Guillo M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan H, Hakobyan RS, Hanretty C, Hardie J, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Kalantarians N, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Kossov M, Krahn Z, Kramer LH, Kubarovsky V, Kuhn J, Kuleshov SV, Lachniet J, Langheinrich J, Lawrence D, Li J, Livingston K, Lu HY, Maccormick M, Marchand C, Markov N, Mattione P, McAleer S, McKinnon B, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Moriya K, Morrow SA, Moteabbed M, Mueller J, Munevar E, Mutchler GS, Nadel-Turonski P, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, O'Rielly GV, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Anefalos Pereira S, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Sabatié F, Salamanca J, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shvedunov NV, Skabelin AV, Smith ES, Smith LC, Sober DI, Sokhan D, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Stoler P, Strauch S, Taiuti M, Tedeschi DJ, Thoma U, Tkabladze A, Tkachenko S, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Watts DP, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang J, Zhao B, and Zhao ZW
Abstract: The reaction 2H(e,e'p)n has been studied with full kinematic coverage for photon virtuality 1.75NN transition is the primary contribution at higher momenta.
Published: 2007
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22. Measurement of the N-->Delta(+)(1232) transition at high-momentum transfer by pi(0) electroproduction.

Author: Ungaro M, Stoler P, Aznauryan I, Burkert VD, Joo K, Smith LC, Adams G, Amarian M, Ambrozewicz P, Anghinolfi M, Asryan G, Audit G, Avakian H, Bagdasaryan H, Ball JP, Baltzell NA, Barrow S, Batourine V, Battaglieri M, Bedliski I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Biselli AS, Bonner BE, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Cazes A, Chen S, Cole PL, Coltharp P, Cords D, Corvisiero P, Crabb D, Cummings JP, Sanctis ED, Devita R, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dharmawardane KV, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Eugenio P, Fatemi R, Fedotov G, Feldman G, Feuerbach RJ, Funsten H, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz J, Gordon CI, Gothe RW, Griffioen KA, Guidal M, Guillo M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Hersman FW, Hleiqawi I, Holtrop M, Hicks K, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Ito MM, Jenkins D, Jo HS, Juengst HG, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Kossov M, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Lee T, Li J, Livingston K, Marchand C, Markov N, McAleer S, McKinnon B, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morand L, Morrow SA, Mueller J, Mutchler GS, Napolitano J, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula M, Niyazov RA, Nozar M, O'rielly GV, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Rubin PD, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Skabelin AV, Smith ES, Sober DI, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Strakovsky II, Strauch S, Taiuti M, Tedeschi DJ, Thoma U, Tkabladze A, Todor L, Tkachenko S, Tur C, Vineyard MF, Vlassov AV, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang B, Zhang J, and Zhao B
Abstract: We report a new measurement of the exclusive electroproduction reaction gamma(*)p-->pi(0)p to explore the evolution from soft nonperturbative physics to hard processes via the Q(2) dependence of the magnetic (M(1+)), electric (E(1+)), and scalar (S(1+)) multipoles in the N-->Delta transition. 9000 differential cross section data points cover W from threshold to 1.4 GeV/c(2), 4pi center-of-mass solid angle, and Q(2) from 3 to 6 GeV(2)/c(2), the highest yet achieved. It is found that the magnetic form factor G(M)(*) decreases with Q(2) more steeply than the proton magnetic form factor, the ratio E(1+)/M(1+) is small and negative, indicating strong helicity nonconservation, and the ratio S(1+)/M(1+) is negative, while its magnitude increases with Q(2).
Published: 2006
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23. Search for Theta++ pentaquarks in the exclusive reaction gammap-->K+K-p.

Author: Kubarovsky V, Battaglieri M, De Vita R, Goett J, Guo L, Mutchler GS, Stoler P, Weygand DP, Ambrozewicz P, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Batourine V, Bedlinskiy I, Bellis M, Benmouna N, Berman BL, Biselli AS, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Chen S, Clinton E, Cole PL, Collins P, Coltharp P, Crabb D, Crannell H, Crede V, Cummings JP, De Masi R, Dale D, De Sanctis E, Degtyarenko PV, Deur A, Dharmawardane KV, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Eugenio P, Fedotov G, Funsten H, Gabrielyan MY, Gan L, Garçon M, Gasparian A, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Glamazdin O, Goetz JT, Golovach E, Gonenc A, Gordon CI, Gothe RW, Griffioen KA, Guidal M, Guler N, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan RS, Hardie J, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Kossov M, Kramer LH, Kuhn J, Kuhn SE, Kuleshov SV, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Lee T, Li J, Livingston K, Lu H, MacCormick M, Markov N, McKinnon B, Mecking BA, Melone JJ, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mochalov V, Mokeev V, Morand L, Morrow SA, Moteabbed M, Nadel-Turonski P, Nakagawa I, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Pozdniakov S, Price JW, Prok Y, Protopopescu D, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shvedunov NV, Smith ES, Smith LC, Sober DI, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Strakovsky II, Strauch S, Taiuti M, Tedeschi DJ, Teymurazyan A, Thoma U, Tkabladze A, Tkachenko S, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Weinstein LB, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang J, and Zhao B
Abstract: The reaction gammap --> pK+K- was studied at Jefferson Lab with photon energies from 1.8 to 3.8 GeV using a tagged photon beam. The goal was to search for a Theta++ pentaquark, a narrow, doubly charged baryon state having strangeness S=+1 and isospin I=1, in the pK+ invariant mass spectrum. No statistically significant evidence of a Theta++ was found. Upper limits on the total and differential cross section for the reaction gammap --> K-Theta++ were obtained in the mass range from 1.5 to 2.0 GeV/c2, with an upper limit for a narrow resonance with a mass M(Theta++) = 1.54 GeV/c2 of about 0.15 nb, 95% C.L.. This result places a stringent upper limit on the Theta++ width Gamma(Theta++) <0.1 MeV/c2.
Published: 2006
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24. Measurement of deeply virtual compton scattering with a polarized-proton target.

Author: Chen S, Avakian H, Burkert VD, Eugenio P, Adams G, Amarian M, Ambrozewicz P, Anghinolfi M, Asryan G, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Barrow S, Batourine V, Battaglieri M, Beard K, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Biselli AS, Bonner BE, Bouchigny S, Boiarinov S, Bosted P, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Carnahan B, Cazes A, Cole PL, Collins P, Coltharp P, Cords D, Corvisiero P, Crabb D, Crannell H, Crede V, Cummings JP, DeMasi R, DeVita R, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, El Fassi L, Elouadrhiri L, Fatemi R, Fedotov G, Feldman G, Feuerbach RJ, Forest TA, Funsten H, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Golovatch E, Gonenc A, Gothe RW, Griffioen KA, Guidal M, Guillo M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan H, Hakobyan RS, Hardie J, Heddle D, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Huertas M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Keith C, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klusman M, Kossov M, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov SV, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Li J, Lima AC, Livingston K, Lu H, Lukashin K, MacCormick M, Markov N, McAleer S, McKinnon B, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morand L, Morrow SA, Moteabbed M, Mueller J, Mutchler GS, Nadel-Turonski P, Napolitano J, Nasseripour R, Natasha N, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, O'Rielly GV, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Philips SA, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Popa I, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Rowntree D, Rubin PD, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shaw J, Shvedunov NV, Skabelin AV, Smith ES, Smith LC, Sober DI, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Stoler P, Strakovsky II, Strauch S, Suleiman R, Taiuti M, Tedeschi DJ, Thoma U, Tkabladze A, Tkachenko S, Todor L, Tur C, Ungaro M, Vanderhaeghen M, Vineyard MF, Vlassov AV, Watts DP, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Yun J, Zana L, Zhang J, Zhao B, and Zhao Z
Abstract: The longitudinal target-spin asymmetry AUL for the exclusive electroproduction of high-energy photons was measured for the first time in ep-->e;'pgamma. The data have been accumulated at JLab with the CLAS spectrometer using 5.7 GeV electrons and a longitudinally polarized NH3 target. A significant azimuthal angular dependence was observed, resulting from the interference of the deeply virtual Compton scattering and Bethe-Heitler processes. The amplitude of the sinvarphi moment is 0.252+/-0.042stat+/-0.020sys. Theoretical calculations are in good agreement with the magnitude and the kinematic dependence of the target-spin asymmetry, which is sensitive to the generalized parton distributions H and H.
Published: 2006
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25. Search for the Theta+ Pentaquark in the gammad--> DeltanK+ reaction measured with the CLAS spectrometer.

Author: Niccolai S, Mirazita M, Rossi P, Baltzell NA, Carman DS, Hicks K, McKinnon B, Mibe T, Stepanyan S, Tedeschi DJ, Adams G, Ambrozewicz P, Anefalos Pereira S, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Batourine V, Battaglieri M, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Biselli AS, Boiarinov S, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carnahan B, Chen S, Cole PL, Collins P, Coltharp P, Crabb D, Crannell H, Crede V, Cummings JP, Dashyan N, Degtyarenko PV, De Masi R, Deppman A, De Sanctis E, Deur A, Devita R, Dharmawardane KV, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dzyubak OP, Egiyan H, Egiyan KS, El Fassi L, Elouadrhiri L, Eugenio P, Fedotov G, Feldman G, Funsten H, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gonenc A, Gordon CI, Gothe RW, Griffioen KA, Guidal M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hafidi K, Hakobyan H, Hakobyan RS, Hardie J, Hersman FW, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Isupov EL, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Kossov M, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov SV, Lachniet J, Langheinrich J, Lawrence D, Lee T, Li J, Livingston K, Lu H, MacCormick M, Markov N, Mecking BA, Mellor J, Melone JJ, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Miskimen R, Mokeev V, Morand L, Morrow SA, Moteabbed M, Mutchler GS, Nadel-Turonski P, Napolitano J, Nasseripour R, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, de Oliveira Echeimberg J, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shvedunov NV, Smith ES, Smith LC, Sober DI, Stavinsky A, Stepanyan SS, Stokes BE, Stoler P, Strakovsky II, Strauch S, Taiuti M, Thoma U, Tkabladze A, Tkachenko S, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Watts DP, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang J, Zhao B, and Zhao Z
Abstract: For the first time, the reaction gammad-->DeltanK+ has been analyzed in order to search for the exotic pentaquark baryon Theta+(1540). The data were taken at Jefferson Laboratory, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the nK+ invariant-mass distribution. The upper limit on the gammad-->DeltaTheta+ integrated cross section has been calculated and found to be between 5 and 25 nb, depending on the production model assumed. The upper limit on the differential cross section is also reported.
Published: 2006
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26. Search for the Theta+ pentaquark in the reaction gammad --> pK-K+n.

Author: McKinnon B, Hicks K, Baltzell NA, Carman DS, Mestayer MD, Mibe T, Mirazita M, Niccolai S, Rossi P, Stepanyan S, Tedeschi DJ, Ambrozewicz P, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Batourine V, Battaglieri M, Bedlinskiy I, Bellis M, Benmouna N, Berman BL, Biselli AS, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Chen S, Cole PL, Collins P, Coltharp P, Crabb D, Crede V, Dale D, De Masi R, DeVita R, De Sanctis E, Degtyarenko PV, Deur A, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Eugenio P, Fedotov G, Feldman G, Funsten H, Gabrielyan M, Gan L, Garçon M, Gasparian A, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gonenc A, Gothe RW, Griffioen KA, Guidal M, Guler N, Guo L, Gyurjyan V, Hakobyan RS, Hersman FW, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Kossov M, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov SV, Lachniet J, Langheinrich J, Lawrence D, Livingston K, Lu H, MacCormick M, Mecking BA, Meyer CA, Mikhailov K, Miskimen R, Mokeev V, Morrow SA, Moteabbed M, Mutchler GS, Nakagawa I, Nadel-Turonski P, Nasseripour R, Niculescu G, Niculescu I, Niczyporuk BB, Niroula MR, Niyazov RA, Nozar M, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Pierce J, Pivnyuk N, Pogorelko O, Pozdniakov S, Price JW, Prok Y, Protopopescu D, Raue BA, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Smith ES, Smith LC, Sober DI, Stavinsky A, Stepanyan SS, Stokes BE, Stoler P, Strakovsky II, Strauch S, Taiuti M, Teymurazyan A, Thoma U, Tkabladze A, Tkachenko S, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang J, Zhao B, and Zhao Z
Abstract: A search for the Theta+ in the reaction gammad --> pK-K+n was completed using the CLAS detector at Jefferson Lab. A study of the same reaction, published earlier, reported the observation of a narrow Theta+ resonance. The present experiment, with more than 30 times the integrated luminosity of our earlier measurement, does not show any evidence for a narrow pentaquark resonance. The angle-integrated upper limit on Theta+ production in the mass range of 1.52-1.56 GeV/c2 for the gammad --> pK-Theta+ reaction is 0.3 nb (95% C.L.). This upper limit depends on assumptions made for the mass and angular distribution of Theta+ production. Using Lambda(1520) production as an empirical measure of rescattering in the deuteron, the cross section upper limit for the elementary gamman --> K-Theta+ reaction is estimated to be a factor of 10 higher, i.e., approximately 3 nb (95% C.L.).
Published: 2006
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27. Measurement of two- and three-nucleon short-range correlation probabilities in nuclei.

Author: Egiyan KS, Dashyan NB, Sargsian MM, Strikman MI, Weinstein LB, Adams G, Ambrozewicz P, Anghinolfi M, Asavapibhop B, Asryan G, Avakian H, Baghdasaryan H, Baillie N, Ball JP, Baltzell NA, Batourine V, Battaglieri M, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Biselli AS, Bonner BE, Bouchigny S, Boiarinov S, Bradford R, Branford D, Brooks WK, Bültmann S, Burkert VD, Bultuceanu C, Calarco JR, Careccia SL, Carman DS, Carnahan B, Chen S, Cole PL, Coltharp P, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, DeVita R, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Djalali C, Dodge GE, Donnelly J, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Fedotov G, Feuerbach RJ, Forest TA, Funsten H, Gavalian G, Gevorgyan NG, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Golovatch E, Gothe RW, Griffioen KA, Guidal M, Guillo M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hardie J, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hu J, Huertas M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko A, Klusman M, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Kuleshov S, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Lee T, Livingston K, Maximon LC, McAleer S, McKinnon B, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morrow SA, Mueller J, Mutchler GS, Nadel-Turonski P, Napolitano J, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, O'Relly GV, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Peterson C, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Rowntree D, Rubin PD, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shaw J, Smith ES, Smith LC, Sober DI, Stavinsky A, Stepanyan S, Stokes BE, Stoler P, Strauch S, Suleiman R, Taiuti M, Taylor S, Tedeschi DJ, Thompson R, Tkabladze A, Tkachenko S, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Yun J, Zana L, and Zhang J
Abstract: The ratios of inclusive electron scattering cross sections of 4He, 12C, and 56Fe to 3He have been measured at 1 < xB <. At Q2 > 1.4 GeV2, the ratios exhibit two separate plateaus, at 1.5 < xB < 2 and at xB > 2.25. This pattern is predicted by models that include 2- and 3-nucleon short-range correlations (SRC). Relative to A = 3, the per-nucleon probabilities of 3-nucleon SRC are 2.3, 3.1, and 4.4 times larger for A = 4, 12, and 56. This is the first measurement of 3-nucleon SRC probabilities in nuclei.
Published: 2006
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28. Eta' photoproduction on the proton for photon energies from 1.527 to 2.227 GeV.

Author: Dugger M, Ball JP, Collins P, Pasyuk E, Ritchie BG, Adams G, Ambrozewicz P, Anciant E, Anghinolfi M, Asavapibhop B, Asryan G, Audit G, Avakian H, Bagdasaryan H, Baillie N, Baltzell NA, Barrow S, Batourine V, Battaglieri M, Beard K, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Bianchi N, Biselli AS, Bonner BE, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Carnahan B, Chen S, Cole PL, Coleman A, Coltharp P, Cords D, Corvisiero P, Crabb D, Crannell H, Credé V, Cummings JP, De Sanctis E, DeVita R, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Donnelly J, Doughty D, Dragovitsch P, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Fedotov G, Feldman G, Feuerbach RJ, Forest TA, Funsten H, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gothe RW, Griffioen KA, Guidal M, Guillo M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hu J, Huertas M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Lee T, Lima AC, Livingston K, Lukashin K, Manak JJ, Marchand C, Maximon LC, McAleer S, McKinnon B, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morrow SA, Muccifora V, Mueller J, Mutchler GS, Nadel-Turonski P, Napolitano J, Nasseripour R, Niccolai S, Niculescu G, Niczyporuk BB, Niyazov RA, Nozar M, O'Rielly GV, Osipenko M, Ostrovidov AI, Park K, Paterson C, Philips SA, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ronchetti F, Rosner G, Rossi P, Rowntree D, Rubin PD, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Stoler P, Strakovsky II, Strauch S, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Tkabladze A, Tkachenko S, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Yun J, Zana L, and Zhang J
Abstract: Differential cross sections for the reaction gamma p --> eta' p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data suggest for the first time the coupling of the eta'N channel to both the S11(1535) and P11(1710) resonances, known to couple strongly to the etaN channel in photoproduction on the proton, and the importance of J = 3/2 resonances in the process.
Published: 2006
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29. Search for Theta+ (1540) Pentaquark in High-Statistics Measurement of gammap-->K0K+n at CLAS.

Author: Battaglieri M, De Vita R, Kubarovsky V, Guo L, Mutchler GS, Stoler P, Weygand DP, Ambrozewicz P, Anghinolfi M, Asryan G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Batourine V, Bedlinskiy I, Bellis M, Benmouna N, Berman BL, Biselli AS, Bouchigny S, Boiarinov S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Chen S, Clinton E, Cole PL, Coltharp P, Crabb D, Crannell H, Cummings JP, Dale D, De Sanctis E, Degtyarenko PV, Deur A, Dharmawardane KV, Djalali C, Dodge GE, Donnelly J, Doughty D, Dugger M, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Eugenio P, Fedotov G, Funsten H, Gabrielyan MY, Gan L, Garçon M, Gasparian A, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Glamazdin O, Goett J, Goetz JT, Golovach E, Gonenc A, Gordon CI, Gothe RW, Griffioen KA, Guidal M, Guler N, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Kossov M, Kramer LH, Kuhn J, Kuhn SE, Kuleshov SV, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Lee T, Li J, Livingston K, McKinnon B, Mecking BA, Melone JJ, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mochalov V, Mokeev V, Morand L, Morrow SA, Nadel-Turonski P, Nakagawa I, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Pozdniakov S, Price JW, Prok Y, Protopopescu D, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Smith ES, Smith LC, Sober DI, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Strakovsky II, Strauch S, Taiuti M, Tedeschi DJ, Teymurazyan A, Thoma U, Tkabladze A, Tkachenko S, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Weinstein LB, Williams M, Wolin E, Wood MH, Yegneswaran A, Zana L, Zhang J, and Zhao B
Abstract: The exclusive reaction gammap-->K0K+n was studied in the photon energy range between 1.6 and 3.8 GeV searching for evidence of the exotic baryon Theta+ (1540)-->nK+. The decay to nK+requires the assignment of strangeness S=+1 to any observed resonance. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility corresponding to an integrated luminosity of 70 pb-1. No evidence for the Theta+ pentaquark was found. Upper limits were set on the production cross section as function of center-of-mass angle and nK+ mass. The 95% C.L. upper limit on the total cross section for a narrow resonance at 1540 MeV was found to be 0.8 nb.
Published: 2006
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30. Beam-helicity asymmetries in double-charged-pion photoproduction on the proton.

Author: Strauch S, Berman BL, Adams G, Ambrozewicz P, Anghinolfi M, Asavapibhop B, Asryan G, Audit G, Avakian H, Bagdasaryan H, Baillie N, Ball JP, Baltzell NA, Barrow S, Batourine V, Battaglieri M, Beard K, Bedlinskiy I, Bektasoglu M, Bellis M, Benmouna N, Bennhold C, Biselli AS, Boiarinov S, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Bültmann S, Burkert VD, Butuceanu C, Calarco JR, Careccia SL, Carman DS, Carnahan B, Chen S, Cole PL, Coleman A, Coltharp P, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, Degtyarenko PV, Denizli H, Dennis L, De Sanctis E, Deur A, Devita R, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Donnelly J, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Fedotov G, Feldman G, Feuerbach RJ, Fix A, Forest TA, Funsten H, Gavalian G, Gilfoyle GP, Giovanetti KL, Girod FX, Goetz JT, Gothe RW, Griffioen KA, Guidal M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hu J, Huertas M, Hyde-Wright CE, Ilieva Y, Ireland DG, Ishkhanov BS, Ito MM, Jenkins D, Jo HS, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kubarovsky V, Kuhn J, Kuhn SE, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Lee T, Lima AC, Livingston K, Lukashin K, Manak JJ, Marchand C, McAleer S, McKinnon B, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mibe T, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morrow SA, Muccifora V, Mueller J, Mutchler GS, Nadel-Turonski P, Napolitano J, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'rielly GV, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Paterson C, Philips SA, Pierce J, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Roberts W, Ronchetti F, Rosner G, Rossi P, Rowntree D, Rubin PD, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Skabelin AV, Smith ES, Smith LC, Sober DI, Stavinsky A, Stepanyan SS, Stepanyan S, Stokes BE, Stoler P, Strakovsky II, Suleiman R, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Tkabladze A, Tkachenko S, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weygand DP, Williams M, Wolin E, Wood MH, Yegneswaran A, Yun J, Zana L, and Zhang J
Abstract: Beam-helicity asymmetries for the two-pion-photoproduction reaction gammap-->ppi(+)pi(-) have been studied for the first time in the resonance region for center-of-mass energies between 1.35 and 2.30 GeV. The experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer using circularly polarized tagged photons incident on an unpolarized hydrogen target. Beam-helicity-dependent angular distributions of the final-state particles were measured. The large cross-section asymmetries exhibit strong sensitivity to the kinematics and dynamics of the reaction. The data are compared with the results of various phenomenological model calculations, and show that these models currently do not provide an adequate description for the behavior of this new observable.
Published: 2005
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31. Onset of asymptotic scaling in deuteron photodisintegration.

Author: Rossi P, Mirazita M, Ronchetti F, De Sanctis E, Adams G, Ambrozewicz P, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Bertozzi W, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carman DS, Carnahan B, Chen S, Cole PL, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Vita R, Degtyarenko PV, Denizli H, Dennis L, Deppman A, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Gai M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Gordon CI, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ilieva Y, Ito MM, Jenkins D, Jo HS, Joo K, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuhn J, Kuhn SE, Lachniet J, Laget JM, Lawrence D, Li J, Lima AC, Livingston K, Lukashin K, Manak JJ, Marchand C, McAleer S, McCarthy J, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mikhailov K, Miskimen R, Mokeev V, Morand L, Morrow SA, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Brien JT, O'Rielly GV, Osipenko M, Ostrovidov A, Park K, Pasyuk E, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Rosner G, Rowntree D, Rubin PD, Sabatié F, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stokes B, Stoler P, Strakovsky II, Strauch S, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Tkabladze A, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B, and Zhou Z
Abstract: We investigate the transition from the nucleon-meson to the quark-gluon description of the strong interaction using the photon energy dependence of the d(gamma,p)n differential cross section for photon energies above 0.5 GeV and center-of-mass proton angles between 30 degrees and 150 degrees. A possible signature for this transition is the onset of cross-section s(-11) scaling with the total energy squared, s, at some proton transverse momentum P(T). The results show that the scaling has been reached for proton transverse momentum above about 1.1 GeV/c. This may indicate that the quark-gluon regime is reached above this momentum.
Published: 2005
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32. Proton source size measurements in the eA-->e'ppX reaction.

Author: Stavinsky AV, Mikhailov KR, Lednicky R, Vlassov AV, Adams G, Ambrozewich P, Anciant E, Anghinolfi M, Asavapibhop B, Asryan G, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Batourine V, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Benmouna N, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bouchigny S, Bradford R, Branford D, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carman DS, Cetina C, Chen S, Cole PL, Cords D, Coleman A, Corvisiero P, Crabb D, Cummings JP, Dashyan N, Sanctis ED, Vita RD, Degtyarenko PV, Denizli H, Dennis L, Deur A, Dharmawardane KV, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Fersch RG, Feuerbach RJ, Forest TA, Funsten H, Garçon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Gordon CI, Gothe RW, Griffioen K, Guidal M, Guillo M, Guler N, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Hersman FW, Hicks K, Hleiqawi I, Holtrop M, Hu J, Hyde-Wright CE, Ireland DG, Ito MM, Jenkins D, Joo K, Juengst HG, Kelley JH, Kellie JD, Khandaker M, Kim DH, Kim KY, Kim K, Kim MS, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov MV, Kramer LH, Kubarovski V, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Leksin GA, Lee T, Li J, Livingston K, Lukashin K, Manak JJ, Marchand C, McAleer S, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mirazita M, Miskimen R, Mokeev V, Morand L, Morrow SA, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Rielly GV, Osipenko M, Ostrovidov AI, Park K, Pasyuk E, Peterson G, Philips SA, Pivnyuk NA, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rosner G, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stepanyan S, Stepanyan SS, Stokes BE, Stoler P, Strakovsky II, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Tkabladze A, Todor L, Tur C, Ungaro M, Vineyard MF, Vorobeyev LS, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Williams M, Wolin E, Wood MH, Yegneswaran A, Yun J, and Zana L
Abstract: Two-proton correlations at small relative momentum q were studied in the eA(3He,4He,C,Fe)-->e(')ppX reaction at E(0)=4.46 GeV using the CLAS detector at Jefferson Lab. The enhancement of the correlation function at small q was found to be in accordance with theoretical expectations. Sizes of the emission region were extracted, and proved to be dependent on A and on the proton momentum. The size of the two-proton emission region for He was measured in eA reactions for the first time.
Published: 2004
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33. Two-nucleon momentum distributions measured in 3He(e,e'pp)n.

Author: Niyazov RA, Weinstein LB, Adams G, Ambrozewicz P, Anciant E, Anghinolfi M, Asavapibhop B, Asryan G, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Bertozzi W, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bouchigny S, Bradford R, Branford D, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carman DS, Carnahan B, Cetina C, Chen S, Ciciani L, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, Dashyan N, DeVita R, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Gordon CI, Gothe RW, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Hersman FW, Hicks K, Holtrop M, Hu J, Hyde-Wright CE, Ilieva Y, Ingram W, Ito MM, Jenkins D, Joo K, Juengst HG, Kelley JH, Kellie J, Khandaker M, Kim DH, Kim KY, Kim K, Kim MS, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Li J, Livingston K, Lukashin K, Manak JJ, Marchand C, McAleer S, McLauchlan S, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mikhailov K, Mirazita M, Miskimen R, Morand L, Morrow SA, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Nozar M, O'Rielly GV, Osipenko M, Park K, Pasyuk E, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Strakovsky II, Strauch S, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, and Zhang B
Abstract: We have measured the 3He(e,e'pp)n reaction at 2.2 GeV over a wide kinematic range. The kinetic energy distribution for "fast" nucleons (p>250 MeV/c) peaks where two nucleons each have 20% or less, and the third nucleon has most of the transferred energy. These fast pp and pn pairs are back to back with little momentum along the three-momentum transfer, indicating that they are spectators. Calculations by Sargsian and by Laget also indicate that we have measured distorted two-nucleon momentum distributions by striking one nucleon and detecting the spectator correlated pair.
Published: 2004
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34. Observation of an exotic baryon with S=+1 in photoproduction from the proton.

Author: Kubarovsky V, Guo L, Weygand DP, Stoler P, Battaglieri M, DeVita R, Adams G, Li J, Nozar M, Salgado C, Ambrozewicz P, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Beard K, Bektasoglu M, Bellis M, Benmouna N, Berman BL, Bianchi N, Biselli AS, Boiarinov S, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carman DS, Carnahan B, Cetina C, Chen S, Ciciani L, Cole PL, Connelly J, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Farhi L, Fatemi R, Feuerbach RJ, Ficenec J, Forest TA, Frolov V, Funsten H, Gaff SJ, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Girard P, Gothe R, Gordon CI, Griffioen K, Guidal M, Guillo M, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hancock D, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Holtrop M, Hu J, Ilieva Y, Ito MM, Jenkins D, Joo K, Juengst HG, Kelley JH, Khandaker M, Kim KY, Kim K, Kim W, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Langheinrich J, Lawrence D, Longhi A, Lukashin K, Major RW, Manak JJ, Marchand C, McAleer S, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morand L, Morrow SA, Mozer MU, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, O'Brien JT, O'Rielly GV, Opper AK, Osipenko M, Park K, Pasyuk E, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Santoro JP, Sapunenko V, Sargsyan M, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith T, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Strakovsky II, Strauch S, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weisberg A, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, and Yun J
Abstract: The reaction gamma p-->pi(+)K(-)K(+)n was studied at Jefferson Laboratory using a tagged photon beam with an energy range of 3-5.47 GeV. A narrow baryon state with strangeness S=+1 and mass M=1555+/-10 MeV/c(2) was observed in the nK(+) invariant mass spectrum. The peak's width is consistent with the CLAS resolution (FWHM=26 MeV/c(2)), and its statistical significance is (7.8+/-1.0)sigma. A baryon with positive strangeness has exotic structure and cannot be described in the framework of the naive constituent quark model. The mass of the observed state is consistent with the mass predicted by the chiral soliton model for the Theta(+) baryon. In addition, the pK(+) invariant mass distribution was analyzed in the reaction gamma p-->K(-)K(+)p with high statistics in search of doubly charged exotic baryon states. No resonance structures were found in this spectrum.
Published: 2004
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35. Observation of an exotic S = +1 baryon in exclusive photoproduction from the deuteron.

Author: Stepanyan S, Hicks K, Carman DS, Pasyuk E, Schumacher RA, Smith ES, Tedeschi DJ, Todor L, Adams G, Ambrozewicz P, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Avakian H, Bagdasaryan H, Ball JP, Barrow SP, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Berman BL, Bianchi N, Biselli AS, Boiarinov S, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carnahan B, Chen S, Ciciani L, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, De Vita R, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Garçon M, Gavalian G, Gilfoyle GP, Giovanetti KL, Gordon CI, Gothe R, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ito MM, Jenkins D, Joo K, Juengst HG, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kubarovsky V, Kuhn SE, Kuhn J, Lachniet J, Lawrence D, Li J, Lima A, Livingston K, Lukashin K, Manak JJ, McAleer S, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morand L, Morrow S, Muccifora V, Mueller J, Murphy LY, Mutchler GS, Napolitano J, Nasseripour R, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Brien J, O'Rielly GV, Opper AK, Osipenko M, Park K, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin P, Sabatié F, Salgado C, Santoro J, Sapunenko V, Serov VS, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith LC, Sober DI, Strakovsky II, Stavinsky A, Stoler P, Suleiman R, Taiuti M, Taylor S, Thoma U, Thompson R, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, and Yun J
Abstract: In an exclusive measurement of the reaction gammad-->K(+)K(-)pn, a narrow peak that can be attributed to an exotic baryon with strangeness S=+1 is seen in the K(+)n invariant mass spectrum. The peak is at 1.542+/-0.005 GeV/c(2) with a measured width of 0.021 GeV/c(2) FWHM, which is largely determined by experimental mass resolution. The statistical significance of the peak is (5.2+/-0.6)sigma. The mass and width of the observed peak are consistent with recent reports of a narrow S=+1 baryon by other experimental groups.
Published: 2003
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36. Measurement of the proton spin structure function g1(x,Q2) for Q2 from 0.15 to 1.6 GeV2 with CLAS.

Author: Fatemi R, Skabelin AV, Burkert VD, Crabb D, De Vita R, Kuhn SE, Minehart R, Adams G, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Bertozzi W, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bosted PE, Bouchigny S, Bradford R, Branford D, Brooks WK, Butuceanu C, Calarco JR, Carman DS, Carnahan B, Cetina C, Ciciani L, Clark R, Cole PL, Coleman A, Connelly J, Cords D, Corvisiero P, Crannell H, Cummings JP, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Farhi L, Feuerbach RJ, Freyberger A, Ficenec J, Forest TA, Frolov V, Funsten H, Gaff SJ, Garçon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Gordon CI, Griffioen KA, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hancock D, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ilieva Y, Ito MM, Jenkins D, Joo K, Keith C, Kelley JH, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Koubarovski V, Kramer LH, Kuang Y, Kuhn J, Lachniet J, Laget JM, Lawrence D, Li J, Livingston K, Longhi A, Lukashin K, Major W, Manak JJ, Marchand C, McAleer S, McNabb JW, Mecking BA, Mehrabyan S, Mestayer MD, Meyer CA, Mikhailov K, Mirazita M, Miskimen R, Morand L, Morrow SA, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Brien JT, O'Rielly GV, Osipenko M, Park K, Pasyuk E, Peterson G, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ritchie BG, Rock SE, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Santoro JP, Sapunenko V, Sargsyan M, Schumacher RA, Seely M, Serov VS, Sharabian YG, Shaw J, Simionatto S, Smith ES, Smith T, Smith LC, Sober DI, Sorrel L, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Strauch S, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B, Zhao J, and Zhou Z
Abstract: Double-polarization asymmetries for inclusive ep scattering were measured at Jefferson Lab using 2.6 and 4.3 GeV longitudinally polarized electrons incident on a longitudinally polarized NH3 target in the CLAS detector. The polarized structure function g(1)(x,Q2) was extracted throughout the nucleon resonance region and into the deep inelastic regime, for Q(2)=0.15-1.64 GeV2. The contributions to the first moment Gamma(1)(Q2)= integral g(1)(x,Q2) dx were determined up to Q(2)=1.2 GeV2. Using a parametrization for g(1) in the unmeasured low x regions, the complete first moment was estimated over this Q2 region. A rapid change in Gamma(1) is observed for Q2<1 GeV2, with a sign change near Q(2)=0.3 GeV2, indicating dominant contributions from the resonance region. At Q(2)=1.2 GeV2 our data are below the perturbative QCD evolved scaling value.
Published: 2003
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37. Measurement of ep-->e' ppi+ pi- and baryon resonance analysis.

Author: Ripani M, Burkert VD, Mokeev V, Battaglieri M, De Vita R, Golovach E, Taiuti M, Adams G, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Beard K, Bektasoglu M, Bellis M, Berman BL, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Calarco JR, Carman DS, Carnahan B, Cazes A, Cetina C, Ciciani L, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Fatemi R, Fedotov G, Feldman G, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Gaff SJ, Gai M, Garçon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ishkhanov B, Ito MM, Jenkins D, Joo K, Kelley JH, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Lawrence D, Li J, Livingston K, Longhi A, Lukashin K, Manak JJ, Marchand C, McAleer S, McCarthy J, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Morand L, Morrow SA, Mozer MU, Muccifora V, Mueller J, Murphy LY, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Rielly GV, Opper AK, Osipenko M, Park K, Pasyuk E, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Quinn B, Raue BA, Riccardi G, Ricco G, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Santoro JP, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Strakovsky II, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B, Zhao J, and Zhou Z
Abstract: The cross section for the reaction ep-->e(')ppi(+)pi(-) was measured in the resonance region for 1.4
Published: 2003
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38. First measurement of transferred polarization in the exclusive ep-->e'K+Lambda--> reaction.

Author: Carman DS, Joo K, Mestayer MD, Raue BA, Adams G, Ambrozewicz P, Anciant E, Anghinolfi M, Armstrong DS, Asavapibhop B, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow SP, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Bennhold C, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Butuceanu C, Calarco JR, Carnahan B, Cazes A, Cetina C, Ciciani L, Clark R, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, DeSanctis E, Degtyarenko PV, Denizli H, Dennis L, DeVita R, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Dzyubak OP, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Eugenio P, Fatemi R, Fedotov G, Feuerbach RJ, Ficenec J, Forest TA, Funsten H, Gaff SJ, Gai M, Garçon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Golovach E, Gordon CI, Griffioen K, Grimes S, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hakobyan RS, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ishkhanov B, Ito MM, Jenkins D, Kelley JH, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Lawrence D, Li J, Livingston K, Longhi A, Lukashin K, Manak JJ, Marchand C, Mart T, McAleer S, McCarthy J, McNabb JW, Mecking BA, Mehrabyan S, Melone JJ, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Mokeev V, Morand L, Morrow SA, Mozer MU, Muccifora V, Mueller J, Murphy LY, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Rielly GV, Opper AK, Osipenko M, Park K, Paschke K, Pasyuk E, Peterson G, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin P, Sabatié F, Sabourov K, Salgado C, Santoro J, Sapunenko V, Schumacher RA, Serov VS, Sharabian YG, Shaw J, Simionatto S, Skabelin AV, Smith ES, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Tur C, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B, Zhao J, and Zhou Z
Abstract: The first measurements of the transferred polarization for the exclusive e-->p-->e(')K+Lambda--> reaction have been performed at Jefferson Laboratory using the CLAS spectrometer. A 2.567 GeV beam was used to measure the hyperon polarization over Q2 from 0.3 to 1.5 (GeV/c)(2), W from 1.6 to 2.15 GeV, and over the full K+ center-of-mass angular range. Comparison with predictions of hadrodynamic models indicates strong sensitivity to the underlying resonance contributions. A nonrelativistic quark-model interpretation of our data suggests that the ssmacr; quark pair is produced with spins predominantly antialigned. Implications for the validity of the most widely used quark-pair creation operator are discussed.
Published: 2003
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39. Photoproduction of the omega meson on the proton at large momentum transfer.

Author: Battaglieri M, Brunoldi M, De Vita R, Laget JM, Osipenko M, Ripani M, Taiuti M, Adams G, Amaryan MJ, Anciant E, Anghinolfi M, Armstrong DS, Asavapibhop B, Asryan G, Audit G, Auger T, Avakian H, Barrow S, Beard K, Bektasoglu M, Berman BL, Bersani A, Bianchi N, Biselli AS, Boiarinov S, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Calarco JR, Capitani GP, Carman DS, Carnahan B, Cazes A, Cetina C, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, DeSanctis E, Degtyarenko PV, Demirchyan R, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Farhi L, Feuerbach RJ, Ficenec J, Forest TA, Freyberger AP, Frolov V, Funsten H, Gaff SJ, Gai M, Garcon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Golovach E, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hancock D, Hardie J, Heddle D, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hyde-Wright CE, Ito MM, Joo K, Kelley JH, Khandaker M, Kim W, Klein A, Klein FJ, Klimenko AV, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Lachniet J, Lawrence D, Lucas M, Lukashin K, Major RW, Manak JJ, Marchand C, McAleer S, McCarthy J, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mikhailov K, Mirazita M, Miskimen R, Mokeev V, Morrow S, Mozer MU, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nelson SO, Niccolai S, Niczyporuk BB, Niyazov RA, Nozar M, O'Brien JT, Opper AK, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Preedom BM, Price JW, Protopopescu D, Qin LM, Raue BA, Reolon AR, Riccardi G, Ricco G, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabourov K, Salgado C, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Skabelin AV, Smith ES, Smith T, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Taylor S, Tedeschi DJ, Todor L, Thoma U, Thompson R, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood M, Yegneswaran A, Yun J, Zhang B, Zhao J, and Zhou Z
Abstract: The differential cross section, dsigma/dt, for omega meson exclusive photoproduction on the proton above the resonance region (2.6
Published: 2003
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40. Eta photoproduction on the proton for photon energies from 0.75 to 1.95 GeV.

Author: Dugger M, Ritchie BG, Ball J, Pasyuk E, Adams G, Anciant E, Anghinolfi M, Asavapibhop B, Audit G, Auger T, Avakian H, Bagdasaryan H, Barrow S, Battaglieri M, Beard K, Bektasoglu M, Bellis M, Berman BL, Bianchi N, Biselli AS, Boiarinov S, Bouchigny S, Bradford R, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Calarco JR, Capitani GP, Carman DS, Carnahan B, Cetina C, Clark R, Cole PL, Coleman A, Connelly J, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, DeSanctis E, DeVita R, Degtyarenko PV, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Farhi L, Fatemi R, Feldman G, Feuerbach RJ, Ficenec J, Forest TA, Frolov V, Funsten H, Gaff SJ, Gai M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Gordon CI, Griffioen K, Guidal M, Guillo M, Guo L, Gyurjyan V, Hadjidakis C, Hancock D, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hyde-Wright CE, Ito MM, Jenkins D, Joo K, Kelley JH, Kellie JD, Khandaker M, Kim W, Klein A, Klein FJ, Klusman M, Kossov M, Koubarovski V, Kramer LH, Kuang Y, Kuhn SE, Kuhn J, Lachniet J, Laget JM, Lawrence D, Li J, Livingston K, Longhi A, Lucas M, Lukashin K, Major W, Manak JJ, Marchand C, McAleer S, McCarthy J, McNabb JW, Mecking BA, Mehrabyan S, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Morand L, Morrow SA, Mozer MU, Muccifora V, Mueller J, Murphy LY, Mutchler GS, Napolitano J, Nasseripour R, Nelson SO, Niccolai S, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Nozar M, O'Brien JT, O'Rielly GV, Opper AK, Park K, Peterson G, Philips SA, Pivnyuk N, Pocanić D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Riccardi G, Ricco G, Ripani M, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Santoro JP, Sanzone-Arenhovel M, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Skabelin AV, Smith ES, Smith T, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Strakovsky II, Strauch S, Taiuti M, Taylor S, Tedeschi DJ, Thoma U, Thompson R, Todor L, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weller H, Weygand DP, Whisnant CS, Witkowski M, Wolin E, Wood MH, Yegneswaran A, Yun J, Zhang B, Zhao J, and Zhou Z
Abstract: Differential cross sections for gammap-->etap have been measured with tagged real photons for incident photon energies from 0.75 to 1.95 GeV. Mesons were identified by missing mass reconstruction using kinematical information for protons scattered in the production process. The data provide the first extensive angular distribution measurements for the process above W=1.75 GeV. Comparison with preliminary results from a constituent quark model support the suggestion that a third S11 resonance with mass approximately 1.8 GeV couples to the etaN channel.
Published: 2002
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41. Measurement of spin-transfer observables in p p-->Lambda Lambda at 1.637 GeV/c.

Author: Bassalleck B, Berdoz A, Bradtke C, Bröders R, Bunker B, Dennert H, Dutz H, Eilerts S, Eyrich W, Fields D, Fischer H, Franklin G, Franz J, Gehring R, Geyer R, Goertz S, Harmsen J, Hauffe J, Heinsius FH, Hertzog D, Johansson T, Jones T, Khaustov P, Kilian K, Kingsberry P, Kriegler E, Lowe J, Meier A, Metzger A, Meyer CA, Meyer W, Moosburger M, Oelert W, Paschke KD, Plückthun M, Pomp S, Quinn B, Radtke E, Reicherz G, Röhrich K, Sachs K, Schmitt H, Schoch B, Sefzick T, Stinzing F, Stotzer R, Tayloe R, and Wirth S
Abstract: Spin-transfer observables for p p-->Lambda Lambda have been measured using a transversely polarized frozen-spin target and a beam momentum of 1.637 GeV/c. Current models of the reaction near threshold are in good agreement with existing measurements performed with unpolarized particles in the initial state but produce conflicting predictions for the spin-transfer observables Dnn and Knn (the normal-to-normal depolarization and polarization transfer), which are measurable only with polarized target or beam. Measurements of Dnn and Knn presented here are found to be in disagreement with predictions from these models.
Published: 2002
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42. Q2 Dependence of quadrupole strength in the gamma*p --> Delta(+)(1232) --> p pi(0) transition.

Author: Joo K, Smith LC, Burkert VD, Minehart R, Aznauryan IG, Elouadrhiri L, Stepanyan S, Adams GS, Amaryan MJ, Anciant E, Anghinolfi M, Armstrong DS, Asavapibhop B, Audit G, Auger T, Avakian H, Barrow S, Bagdasaryan H, Battaglieri M, Beard K, Bektasoglu M, Bertozzi W, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Brooks WK, Calarco JR, Capitani GP, Carman DS, Carnahan B, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings J, De Sanctis E, De Vita R, Degtyarenko PV, Demirchyan RA, Denizli H, Dennis LC, Deppman A, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Efremenko YV, Egiyan H, Egiyan KS, Farhi L, Feuerbach RJ, Ficenec J, Fissum K, Forest TA, Funsten H, Gai M, Gavrilov VB, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Griffioen KA, Guidal M, Guillo M, Gyurjyan V, Hancock D, Hardie J, Heddle D, Heisenberg J, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hyde-Wright CE, Ito MM, Jenkins D, Kelley JH, Khandaker M, Kim KY, Kim W, Klein A, Klein FJ, Klusman M, Kossov M, Kuang Y, Kuhn SE, Laget JM, Lawrence D, Longhi A, Loukachine K, Lucas M, Major RW, Manak JJ, Marchand C, Matthews SK, McAleer S, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mirazita M, Miskimen R, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Niculescu G, Niczyporuk B, Niyazov RA, Ohandjanyan MS, Opper A, Patois Y, Peterson GA, Philips S, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Preedom BM, Price JW, Qin LM, Raue BA, Reolon AR, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Salgado CW, Sanzone M, Sapunenko V, Sargsyan M, Schumacher RA, Sharabian YG, Shaw J, Shuvalov SM, Skabelin A, Smith ES, Smith T, Sober DI, Spraker M, Stoler P, Taiuti M, Taylor S, Tedeschi D, Thompson R, Todor L, Tung TY, Vineyard MF, Vlassov A, Weller H, Weinstein LB, Welsh R, Weygand DP, Whisnant S, Witkowski M, Wolin E, Yegneswaran A, Yun J, Zhou Z, and Zhao J
Abstract: Models of baryon structure predict a small quadrupole deformation of the nucleon due to residual tensor forces between quarks or distortions from the pion cloud. Sensitivity to quark versus pion degrees of freedom occurs through the Q2 dependence of the magnetic (M1+), electric (E1+), and scalar (S1+) multipoles in the gamma*p-->Delta(+)-->p pi(0) transition. We report new experimental values for the ratios E(1+)/M(1+) and S(1+)/M(1+) over the range Q2 = 0.4-1.8 GeV2, extracted from precision p(e,e(')p)pi(0) data using a truncated multipole expansion. Results are best described by recent unitary models in which the pion cloud plays a dominant role.
Published: 2002
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43. First measurement of the double spin asymmetry in (-->)e(-->)p-->e(prime)pi(+)n in the resonance region.

Author: De Vita R, Anghinolfi M, Burkert VD, Dodge GE, Minehart R, Taiuti M, Weller H, Adams G, Amaryan MJ, Anciant E, Armstrong DS, Asavapibhop B, Asryan G, Audit G, Auger T, Avakian H, Bagdasaryan H, Ball JP, Barrow S, Battaglieri M, Beard K, Bektasoglu M, Bianchi N, Biselli AS, Boiarinov S, Bonner BE, Bosted P, Bouchigny S, Branford D, Brooks WK, Bueltmann S, Calarco JR, Capitani GP, Carman DS, Carnahan B, Cazes A, Ciciani L, Cole PL, Coleman A, Connelly J, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, De Sanctis E, Degtyarenko PV, Demirchyan R, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Empl A, Farhi L, Fatemi R, Feuerbach RJ, Ficenec J, Forest TA, Frolov V, Funsten H, Gaff SJ, Gai M, Garçon M, Gavalian G, Gilad S, Gilfoyle GP, Giovanetti KL, Girard P, Golovatch E, Griffioen K, Guidal M, Guillo M, Gyurjyan V, Hadjidakis C, Hancock D, Hardie J, Heddle D, Heimberg P, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hu J, Hyde-Wright CE, Ishkanov BS, Ito MM, Jenkins D, Joo K, Kelley JH, Kellie JD, Khandaker M, Kim KY, Kim K, Kim W, Klein A, Klein FJ, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Lachniet J, Laget JM, Lawrence D, Li J, Livingston K, Longhi A, Loukachine K, Lucas M, Major W, Manak JJ, Marchand C, McAleer S, McCarthy J, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mikhailov K, Mirazita M, Miskimen R, Mokeev V, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nelson SO, Niculescu G, Niculescu I, Niczyporuk BB, Niyazov RA, Opper AK, O'Rielly GV, Osipenko M, Park K, Pasyuk E, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Pozdniakov S, Preedom BM, Price JW, Prok Y, Protopopescu D, Qin LM, Raue BA, Reolon AR, Riccardi G, Ricco G, Ripani M, Ritchie BG, Rock S, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabatié F, Sabourov K, Salgado C, Sapunenko V, Sargsyan M, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Skabelin AV, Smith ES, Smith T, Smith LC, Sober DI, Sorrell L, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Strakovsky II, Taylor S, Tedeschi DJ, Thompson R, Todor L, Ungaro M, Vineyard MF, Vlassov AV, Wang K, Weinstein LB, Weisberg A, Weygand DP, Whisnant CS, Wolin E, Yegneswaran A, Yun J, Zhang B, Zhao J, and Zhou Z
Abstract: The double spin asymmetry in the (-->)e(-->)p --> e(prime)pi(+)n reaction has been measured for the first time in the resonance region for four-momentum transfer Q2 = 0.35-1.5 GeV(2). Data were taken at Jefferson Lab with the CLAS detector using a 2.6 GeV polarized electron beam incident on a polarized solid NH3 target. Comparison with predictions of phenomenological models shows strong sensitivity to resonance contributions. Helicity-1/2 transitions are found to be dominant in the second and third resonance regions. The measured asymmetry is consistent with a faster rise with Q(2) of the helicity asymmetry A1 for the F(15)(1680) resonance than expected from the analysis of the unpolarized data.
Published: 2002
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44. Photoproduction of the rho(0) meson on the proton at large momentum transfer.

Author: Battaglieri M, Anciant E, Anghinolfi M, De Vita R, Golovach E, Laget JM, Mokeev V, Ripani M, Adams G, Amaryan MJ, Armstrong DS, Asavapibhop B, Asryan G, Audit G, Auger T, Avakian H, Barrow S, Beard K, Bektasoglu M, Berman BL, Bianchi N, Biselli AS, Boiarinov S, Branford D, Briscoe WJ, Brooks WK, Burkert VD, Calarco JR, Capitani GP, Carman DS, Carnahan B, Cazes A, Cetina C, Cole PL, Coleman A, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings JP, DeSanctis E, Degtyarenko PV, Demirchyan R, Denizli H, Dennis L, Dharmawardane KV, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Dytman S, Eckhause M, Egiyan H, Egiyan KS, Elouadrhiri L, Farhi L, Feuerbach RJ, Ficenec J, Forest TA, Freyberger AP, Frolov V, Funsten H, Gaff SJ, Gai M, Gilad S, Gilfoyle GP, Giovanetti KL, Griffioen K, Guidal M, Guillo M, Gyurjyan V, Hancock D, Hardie J, Heddle D, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hyde-Wright CE, Ito MM, Joo K, Kelley JH, Khandaker M, Kim W, Klein A, Klein FJ, Klusman M, Kossov M, Kramer LH, Kuang Y, Kuhn SE, Lawrence D, Lucas M, Lukashin K, Major RW, Manak JJ, Marchand C, McAleer S, McCarthy J, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Mikhailov K, Minehart R, Mirazita M, Miskimen R, Muccifora V, Mueller J, Mutchler GS, Napolitano J, Nelson SO, Niczyporuk BB, Niyazov RA, O'Brien JT, Opper AK, Peterson G, Philips SA, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Preedom BM, Price JW, Protopopescu D, Qin LM, Raue BA, Reolon AR, Riccardi G, Ricco G, Ritchie BG, Ronchetti F, Rossi P, Rowntree D, Rubin PD, Sabourov K, Salgado C, Sanzone-Arenhovel M, Sapunenko V, Schumacher RA, Serov VS, Shafi A, Sharabian YG, Shaw J, Skabelin AV, Smith ES, Smith T, Smith LC, Sober DI, Spraker M, Stavinsky A, Stepanyan S, Stoler P, Taiuti M, Taylor S, Tedeschi DJ, Todor L, Thompson R, Vineyard MF, Vlassov AV, Weinstein LB, Weisberg A, Weller H, Weygand DP, Whisnant CS, Wolin E, Wood M, Yegneswaran A, Yun J, Zhang B, Zhao J, and Zhou Z
Abstract: The differential cross section, d sigma/dt, for rho(0) meson photoproduction on the proton above the resonance region was measured up to a momentum transfer -t = 5 GeV2 using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The rho(0) channel was extracted from the measured two charged-pion cross sections by fitting the pi(+)pi(-) and p pi(+) invariant masses. The low momentum transfer region shows the typical diffractive pattern expected from Reggeon exchange. The flatter behavior at large -t cannot be explained solely in terms of QCD-inspired two-gluon exchange models. The data indicate that other processes, like quark interchange, are important to fully describe rho photoproduction.
Published: 2001
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45. The ep -->e'p eta reaction at and above the S11(1535) baryon resonance.

Author: Thompson R, Dytman S, Kim KY, Mueller J, Adams GS, Amaryan MJ, Anciant E, Anghinolfi M, Asavapibhop B, Auger T, Audit G, Avakian H, Barrow S, Battaglieri M, Beard K, Bektasoglu M, Bertozzi W, Bianchi N, Biselli A, Boiarinov S, Bonner BE, Briscoe WJ, Brooks W, Burkert VD, Calarco JR, Capitani G, Carman DS, Carnahan B, Cole PL, Coleman A, Connelly J, Cords D, Corvisiero P, Crabb D, Crannell H, Cummings J, Day D, Degtyarenko PV, Demirchyan RA, Dennis LC, Deppman A, De Sanctis E, De Vita R, Dhuga KS, Djalali C, Dodge GE, Doughty D, Dragovitsch P, Dugger M, Eckhause M, Efremenko YV, Egiyan H, Egiyan KS, Elouadrhiri L, Farhi L, Feuerbach RJ, Ficenec J, Fissum K, Freyberger A, Funsten H, Gai M, Gavrilov VB, Gilfoyle GP, Giovanetti K, Gilad S, Girard P, Griffioen KA, Guidal M, Guillo M, Gyurjyan V, Hancock D, Hardie J, Heddle D, Heisenberg J, Hersman FW, Hicks K, Hicks RS, Holtrop M, Hyde-Wright CE, Ito MM, Jenkins D, Joo K, Kane J, Khandaker M, Kim W, Klein A, Klein FJ, Klusman M, Kossov M, Kuhn SE, Kuang Y, Laget JM, Lawrence D, Leskin GA, Longhi A, Loukachine K, Lucas M, Magahiz R, Major RW, Manak JJ, Marchand C, Matthews SK, McAleer S, McCarthy J, McNabb JW, Mecking BA, Mestayer MD, Meyer CA, Minehart R, Mirazita M, Miskimen R, Muccifora V, Mutchler GS, Napolitano J, Niyazov RA, Ohandjanyan MS, O'Brien JT, Opper A, Patois Y, Peterson GA, Philips S, Pivnyuk N, Pocanic D, Pogorelko O, Polli E, Preedom BM, Price JW, Qin LM, Raue BA, Reolon AR, Riccardi G, Ricco G, Ripani M, Ritchie BG, Ronchetti F, Rossi P, Roudot F, Rowntree D, Rubin PD, Salgado CW, Sanzone M, Sapunenko V, Sarty A, Sargsyan M, Schumacher RA, Shafi A, Sharabian YG, Shaw J, Shuvalov SM, Skabelin A, Smith T, Smith C, Smith ES, Sober DI, Spraker M, Stepanyan S, Stoler P, Taiuti M, Taylor S, Tedeschi D, Tung TY, Vineyard MF, Vlassov A, Weller H, Weinstein LB, Welsh R, Weygand DP, Whisnant S, Witkowski M, Wolin E, Yegneswaran A, Yun J, Zhou Z, and Zhao J
Abstract: New cross sections for the reaction e p-->e p eta are reported for total center of mass energy W = 1.5--1.86 GeV and invariant momentum transfer Q2 = 0.25--1.5 (GeV/c)(2). This large kinematic range allows extraction of important new information about response functions, photocouplings, and eta N coupling strengths of baryon resonances. Newly observed structure at W approximately 1.65 GeV is shown to come from interference between S and P waves and can be interpreted with known resonances. Improved values are derived for the photon coupling amplitude for the S11(1535) resonance.
Published: 2001
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46. Polarized-target asymmetry in pion-proton bremsstrahlung at 298 MeV.

Author: Bosshard A, Amsler C, Bistirlich JA, van den Brandt B, Crowe KM, Döbeli M, Doser M, Haddock RP, Konter JA, Ljungfelt S, Loude JF, Mango S, Meyer CA, Perroud JP, Riedlberger J, Renker D, Schaad M, Sober DI, Truöl P, and Weymuth P
Published: 1990
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47. Observation of a nonspherical pion source in relativistic heavy-ion collisions.

Author: Chacon AD, Bistirlich JA, Bossingham RR, Bowman HR, Clawson CW, Crowe KM, Humanic TJ, Kurck JM, Meyer CA, Rasmussen JO, Hashimoto O, McHarris W, Sullivan JP, and Zajc WA
Published: 1988
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