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1. Strong Interaction Physics at the Luminosity Frontier with 22 GeV Electrons at Jefferson Lab

Author

Accardi, A., Achenbach, P., Adhikari, D., Afanasev, A., Akondi, C. S., Akopov, N., Albaladejo, M., Albataineh, H., Albrecht, M., Almeida-Zamora, B., Amaryan, M., Androić, D., Armstrong, W., Armstrong, D. S., Arratia, M., Arrington, J., Asaturyan, A., Austregesilo, A., Avagyan, H., Averett, T., Gayoso, C. Ayerbe, Bacchetta, A., Balantekin, A. B., Baltzell, N., Barion, L., Barry, P. C., Bashir, A., Battaglieri, M., Bellini, V., Belov, I., Benhar, O., Benkel, B., Benmokhtar, F, Bentz, W., Bertone, V., Bhatt, H., Bianconi, A., Bibrzycki, L., Bijker, R., Binosi, D., Biswas, D., Boër, M., Boeglin, W., Bogacz, S. A., Boglione, M., Bondí, M., Boos, E. E., Bosted, P., Bozzi, G., Brash, E. J., Briceño, R. A., Brindza, P. D., Briscoe, W. J., Brodsky, S. J, Brooks, W. K., Burkert, V. D., Camsonne, A., Cao, T., Cardman, L. S., Carman, D. S., Carpinelli, M, Cates, G. D., Caylor, J., Celentano, A., Celiberto, F. G., Cerutti, M., Chang, Lei, Chatagnon, P., Chen, C., Chen, J-P, Chetry, T., Christopher, A., Christy, E., Chudakov, E., Cisbani, E., Cloët, I. C., Cobos-Martinez, J. J., Cohen, E. O., Colangelo, P., Cole, P. L., Constantinou, M., Contalbrigo, M., Costantini, G., Cosyn, W., Cotton, C., Courtoy, A., Dusa, S. Covrig, Crede, V., Cui, Z. -F., D'Angelo, A., Döring, M., Dalton, M. M., Danilkin, I., Davydov, M., Day, D., De Fazio, F., De Napoli, M., De Vita, R., Dean, D. J., Defurne, M., Deur, A., Devkota, B., Dhital, S., Di Nezza, P., Diefenthaler, M., Diehl, S., Dilks, C., Ding, M., Djalali, C., Dobbs, S., Dupré, R., Dutta, D., Edwards, R. G., Egiyan, H., Ehinger, L., Eichmann, G., Elaasar, M., Elouadrhiri, L., Alaoui, A. El, Fassi, L. El, Emmert, A., Engelhardt, M., Ent, R., Ernst, D. J, Eugenio, P., Evans, G., Fanelli, C., Fegan, S., Fernández-Ramírez, C., Fernandez, L. A., Fernando, I. P., Filippi, A., Fischer, C. S., Fogler, C., Fomin, N., Frankfurt, L., Frederico, T., Freese, A., Fu, Y., Gamberg, L., Gan, L., Gao, F., Garcia-Tecocoatzi, H., Gaskell, D., Gasparian, A., Gates, K, Gavalian, G., Ghoshal, P. K., Giachino, A., Giacosa, F., Giannuzzi, F., Gilfoyle, G. -P., Girod, F-X, Glazier, D. I., Gleason, C., Godfrey, S., Goity, J. L., Golubenko, A. A., Gonzàlez-Solís, S., Gothe, R. W., Gotra, Y., Griffioen, K., Grocholski, O., Grube, B., Guèye, P., Guo, F. -K., Guo, Y., Guo, L., Hague, T. J., Hammoud, N., Hansen, J. -O., Hattawy, M., Hauenstein, F., Hayward, T., Heddle, D., Heinrich, N., Hen, O., Higinbotham, D. W., Higuera-Angulo, I. M., Blin, A. N. Hiller, Hobart, A., Hobbs, T., Holmberg, D. E, Horn, T., Hoyer, P., Huber, G. M., Hurck, P., Hutauruk, P. T. P., Ilieva, Y., Illari, I., Ireland, D. G, Isupov, E. L., Italiano, A., Jaegle, I., Jarvis, N. S., Jenkins, DJ, Jeschonnek, S., Ji, C-R., Jo, H. S., Jones, M., Jones, R. T., Jones, D. C., Joo, K., Junaid, M., Kageya, T., Kalantarians, N., Karki, A., Karyan, G., Katramatou, A. T., Kay, S. J. D, Kazimi, R., Keith, C. D., Keppel, C., Kerbizi, A., Khachatryan, V., Khanal, A., Khandaker, M., Kim, A., Kinney, E. R., Kohl, M., Kotzinian, A., Kriesten, B. T., Kubarovsky, V., Kubis, B., Kuhn, S. E., Kumar, V., Kutz, T., Leali, M., Lebed, R. F., Lenisa, P., Leskovec, L., Li, S., Li, X., Liao, J., Lin, H. -W., Liu, L., Liuti, S., Liyanage, N., Lu, Y., MacGregor, I. J. D., Mack, D. J., Maiani, L, Mamo, K. A., Mandaglio, G., Mariani, C., Markowitz, P., Marukyan, H., Mascagna, V., Mathieu, V., Maxwell, J., Mazouz, M., McCaughan, M., McKeown, R. D., McKinnon, B., Meekins, D., Melnitchouk, W., Metz, A., Meyer, C. A., Meziani, Z. -E., Mezrag, C., Michaels, R., Miller, G. A., Mineeva, T., Miramontes, A. S., Mirazita, M., Mizutani, K., Mkrtchyan, H., Mkrtchyan, A., Moffit, B., Mohanmurthy, P., Mokeev, V. I., Monaghan, P., Montaña, G., Montgomery, R., Moretti, A., Chàvez, J. M. Morgado, Mosel, U., Movsisyan, A., Musico, P., Nadeeshani, S. A, Nadolsky, P. M., Nakamura, S. X., Nazeer, J., Nefediev, A. V., Neupane, K., Nguyen, D., Niccolai, S., Niculescu, I., Niculescu, G., Nocera, E. R., Nycz, M., Olness, F. I., Ortega, P. G., Osipenko, M., Pace, E., Pandey, B, Pandey, P., Papandreou, Z., Papavassiliou, J., Pappalardo, L. L., Paredes-Torres, G., Paremuzyan, R., Park, S., Parsamyan, B., Paschke, K. D., Pasquini, B., Passemar, E., Pasyuk, E., Patel, T., Paudel, C., Paul, S. J., Peng, J-C., Pentchev, L., Perrino, R., Perry, R. J., Peters, K., Petratos, G. G., Phelps, W., Piasetzky, E., Pilloni, A., Pire, B., Pitonyak, D., Pitt, M. L., Polosa, A. D., Pospelov, M., Postuma, A. C., Poudel, J., Preet, L., Prelovsek, S., Price, J. W., Prokudin, A., Puckett, A. J. R., Pybus, J. R., Qin, S. -X., Qiu, J. -W., Radici, M., Rashidi, H., Rathnayake, A. D, Raue, B. A., Reed, T., Reimer, P. E., Reinhold, J., Richard, J. -M., Rinaldi, M., Ringer, F., Ripani, M., Ritman, J., West, J. Rittenhouse, Rivero-Acosta, A., Roberts, C. D., Rodas, A., Rodini, S., Rodríguez-Quintero, J., Rogers, T. C., Rojo, J., Rossi, P., Rossi, G. C., Salmè, G., Santiesteban, S. N., Santopinto, E., Sargsian, M., Sato, N., Schadmand, S., Schmidt, A., Schmidt, S. M, Schnell, G., Schumacher, R. A., Schweitzer, P., Scimemi, I., Scott, K. C, Seay, D. A, Segovia, J., Semenov-Tian-Shansky, K., Seryi, A., Sharda, A. S, Shepherd, M. R., Shirokov, E. V., Shrestha, S., Shrestha, U., Shvedunov, V. I., Signori, A., Slifer, K. J., Smith, W. A., Somov, A., Souder, P., Sparveris, N., Spizzo, F., Spreafico, M., Stepanyan, S., Stevens, J. R., Strakovsky, I. I., Strauch, S., Strikman, M., Su, S., Sumner, B. C. L., Sun, E., Suresh, M., Sutera, C., Swanson, E. S., Szczepaniak, A. P, Sznajder, P., Szumila-Vance, H., Szymanowski, L., Tadepalli, A. -S., Tadevosyan, V., Tamang, B., Tarasov, V. V., Thiel, A., Tong, X. -B., Tyson, R., Ungaro, M., Urciuoli, G. M., Usman, A., Valcarce, A., Vallarino, S., Vaquera-Araujo, C. A., Venturelli, L., Vera, F., Vladimirov, A., Vossen, A., Wagner, J., Wei, X., Weinstein, L. B., Weiss, C., Williams, R., Winney, D., Wojtsekhowski, B., Wood, M. H., Xiao, T., Xu, S. -S., Ye, Z., Yero, C., Yuan, C. -P., Yurov, M., Zachariou, N., Zhang, Z., Zhao, Z. W., Zhao, Y., Zheng, X., Zhou, X., Ziegler, V., Zihlmann, B., de Paula, W, and de Téramond, G. F.

Subjects
Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract

This document presents the initial scientific case for upgrading the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab (JLab) to 22 GeV. It is the result of a community effort, incorporating insights from a series of workshops conducted between March 2022 and April 2023. With a track record of over 25 years in delivering the world's most intense and precise multi-GeV electron beams, CEBAF's potential for a higher energy upgrade presents a unique opportunity for an innovative nuclear physics program, which seamlessly integrates a rich historical background with a promising future. The proposed physics program encompass a diverse range of investigations centered around the nonperturbative dynamics inherent in hadron structure and the exploration of strongly interacting systems. It builds upon the exceptional capabilities of CEBAF in high-luminosity operations, the availability of existing or planned Hall equipment, and recent advancements in accelerator technology. The proposed program cover various scientific topics, including Hadron Spectroscopy, Partonic Structure and Spin, Hadronization and Transverse Momentum, Spatial Structure, Mechanical Properties, Form Factors and Emergent Hadron Mass, Hadron-Quark Transition, and Nuclear Dynamics at Extreme Conditions, as well as QCD Confinement and Fundamental Symmetries. Each topic highlights the key measurements achievable at a 22 GeV CEBAF accelerator. Furthermore, this document outlines the significant physics outcomes and unique aspects of these programs that distinguish them from other existing or planned facilities. In summary, this document provides an exciting rationale for the energy upgrade of CEBAF to 22 GeV, outlining the transformative scientific potential that lies within reach, and the remarkable opportunities it offers for advancing our understanding of hadron physics and related fundamental phenomena., Comment: Updates to the list of authors; Preprint number changed from theory to experiment; Updates to sections 4 and 6, including additional figures

Published
2023

2. Probing the core of the strong nuclear interaction

Author

Schmidt, A., Pybus, J. R., Weiss, R., Segarra, E. P., Hrnjic, A., Denniston, A., Hen, O., Piasetzky, E., Weinstein, L. B., Barnea, N., Strikman, M., Larionov, A., Higinbotham, D., Adhikari, S., Amaryan, M., Angelini, G., Asryan, G., Atac, H., Avakian, H., Gayoso, C. Ayerbe, Baashen, L., Barion, L., Bashkanov, M., Battaglieri, M., Beck, A., Bedlinskiy, I., Benmokhtar, F., Bianconi, A., Biselli, A. S., Bossu, F., Biarinov, S., Briscoe, W. J., Brooks, W., Burkert, V. D., Cao, F., Carman, D. S., Carvajal, J. C., Celentano, A., Chatagnon, P., Chetry, T., Ciullo, G., Clark, L., Cohen, E., Cole, P. L., 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., Dugger, M., Dupre, R., Egiyan, H., Ehrhart, M., Alaoui, A. El, Fassi, L. El, Eugenio, P., Filippi, A., Forest, T. A., Gavalian, G., Gilad, S., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Giuseppe, C., Glazier, D. I., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Hauenstein, F., Hayward, T. B., Hicks, K., Holtrop, M., Ilieva, Y., Illari, I., Ireland, D., Ishkanov, B. S., Isupov, E. L., Jenkins, D., Jo, H. S., Joo, K., Keller, D., Khachatryan, M., Khanal, A., Khandaker, M., Kim, C. W., Kim, W., Klein, F. J., Korover, I., Kubarovsky, V., Lanza, L., Leali, M., Lenisa, P., MacGregor, I. J. D., Marchand, D., Markov, N., Marsicano, L., Mascagna, V., Beck, S. May-Tal, McKinnon, B., Mirazita, M., Mokeev, V., Camacho, C. Munoz, Mustapha, B., Nadel-Turonski, P., Nanda, S., Niccolai, S., Niculescu, G., Osipenko, M., Ostrovidov, A. I., Paolone, M., Pappalardo, L. L., Paremuzyan, R., Park, K., Pasyuk, E., Patsyuk, M., Phelps, W., Pogorelko, O., Price, J. W., Prok, Y., Protopopescu, D., Ripani, M., Riser, D., Rizzo, A., Rosner, G., Rossi, P., Sabatie, F., Salgado, C., Schmookler, B., Schumacher, R. A., Sharabian, Y. G., Shrestha, U., Skorodumina, Iu., Sokhan, D., Soto, O., Sparveris, N., Stepanyan, S., Strakovsky, I. I., Strauch, S., Tan, J. A., Tyler, N., Ungaro, M., Venturelli, L., Voskanyan, H., Voutier, E., Wang, R., Watts, D. P., Wei, X., Wood, M. H., Zachariou, N., Zhang, J., Zhao, Z. W., and Zheng, X.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The strong nuclear interaction between nucleons (protons and neutrons) is the effective force that holds the atomic nucleus together. This force stems from fundamental interactions between quarks and gluons (the constituents of nucleons) that are described by the equations of Quantum Chromodynamics (QCD). However, as these equations cannot be solved directly, physicists resort to describing nuclear interactions using effective models that are well constrained at typical inter-nucleon distances in nuclei but not at shorter distances. This limits our ability to describe high-density nuclear matter such as in the cores of neutron stars. Here we use high-energy electron scattering measurements that isolate nucleon pairs in short-distance, high-momentum configurations thereby accessing a kinematical regime that has not been previously explored by experiments, corresponding to relative momenta above 400 MeV/c. As the relative momentum between two nucleons increases and their separation thereby decreases, we observe a transition from a spin-dependent tensor-force to a predominantly spin-independent scalar-force. These results demonstrate the power of using such measurements to study the nuclear interaction at short-distances and also support the use of point-like nucleons with two- and three-body effective interactions to describe nuclear systems up to densities several times higher than the central density of atomic nuclei., Comment: Total 26 pages, 13 figures. Main text: 8 pages, 3 figures. Methods section: 6 pages. Extended Data: 8 figures, 1 table. Supplementary Materials: 8 pages, 2 figures

Published
2020
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3. Momentum sharing in imbalanced Fermi systems

Author

Hen, O., Sargsian, M., Weinstein, L. B., Piasetzky, E., Hakobyan, H., Higinbotham, D. W., Braverman, M., Brooks, W. K., Gilad, S., Adhikari, K. P., Arrington, J., Asryan, G., Avakian, H., Ball, J., Baltzell, N. A., Battaglieri, M., Beck, A., Beck, S. May-Tal, Bedlinskiy, I., Bertozzi, W., Biselli, A., Burkert, V. D., Cao, T., Carman, D. S., Celentano, A., Chandavar, S., Colaneri, L., Cole, P. L., Crede, V., DAngelo, A., De Vita, R., Deur, A., Djalali, C., Doughty, D., Dugger, M., Dupre, R., Egiyan, H., Alaoui, A. El, Fassi, L. El, Elouadrhiri, L., Fedotov, G., Fegan, S., Forest, T., Garillon, B., Garcon, M., Gevorgyan, N., Ghandilyan, Y., Gilfoyle, G. P., Girod, F. X., Goetz, J. T., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hanretty, C., Hattawy, M., Hicks, K., Holtrop, M., Hyde, C. E., Ilieva, Y., Ireland, D. G., Ishkanov, B. I., Isupov, E. L., Jiang, H., Jo, H. S., Joo, K., Keller, D., Khandaker, M., Kim, A., Kim, W., Klein, F. J., Koirala, S., Korover, I., Kuhn, S. E., Kubarovsky, V., Lenisa, P., Levine, W. I., Livingston, K., Lowry, M., Lu, H. Y., MacGregor, I. J. D., Markov, N., Mayer, M., McKinnon, B., Mineeva, T., Mokeev, V., Movsisyan, A., Camacho, C. Munoz, Mustapha, B., Nadel-Turonski, P., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Pappalardo, L. L., Paremuzyan, R., Park, K., Pasyuk, E., Phelps, W., Pisano, S., Pogorelko, O., Price, J. W., Procureur, S., Prok, Y., Protopopescu, D., Puckett, A. J. R., Rimal, D., Ripani, M., Ritchie, B. G., Rizzo, A., Rosner, G., Rossi, P., Roy, P., Sabatie, F., Schott, D., Schumacher, R. A., Sharabian, Y. G., Smith, G. D., Shneor, R., Sokhan, D., Stepanyan, S. S., Stepanyan, S., Stoler, P., Strauch, S., Sytnik, V., Taiuti, M., Tkachenko, S., Ungaro, M., Vlassov, A. V., Voutier, E., Watts, D., Walford, N. K., Wei, X., Wood, M. H., Wood, S. A., Zachariou, N., Zana, L., Zhao, Z. W., Zheng, X., and Zonta, I.

Subjects
Nuclear Experiment, Condensed Matter - Quantum Gases, Nuclear Theory
Abstract

The atomic nucleus is composed of two different kinds of fermions, protons and neutrons. If the protons and neutrons did not interact, the Pauli exclusion principle would force the majority fermions (usually neutrons) to have a higher average momentum. Our high-energy electron scattering measurements using 12C, 27Al, 56Fe and 208Pb targets show that, even in heavy neutron-rich nuclei, short-range interactions between the fermions form correlated high-momentum neutron-proton pairs. Thus, in neutron-rich nuclei, protons have a greater probability than neutrons to have momentum greater than the Fermi momentum. This finding has implications ranging from nuclear few body systems to neutron stars and may also be observable experimentally in two-spin state, ultra-cold atomic gas systems., Comment: Published in Science. 10 pages, 3 figures

Published
2014
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4. First Observation of Large Missing-Momentum (e,e'p) Cross-Section Scaling and the onset of Correlated-Pair Dominance in Nuclei

Author

Korover, I., Denniston, A. W., Kiral, A., Schmidt, A., Lovato, A., Rocco, N., Nikolakopoulos, A., Weinstein, L. B., Piasetzky, E., Hen, O., Amaryan, M. J., Angelini, Giovanni, Atac, H., Baltzell, N. A., Barion, L., Battaglieri, M., Bedlinskiy, I., Benmokhtar, Fatiha, Bianconi, A., Biondo, L., Biselli, A. S., Bossù, F., Boiarinov, S., Briscoe, W. J., Bulumulla, D., Burkert, V. D., Carman, D. S., Carvajal, J. C., Caudron, M., Chatagnon, P., Chetry, T., Ciullo, G., Clark, L., Cole, P. L., Contalbrigo, M., Costantini, G., D Angelo, A., Dashyan, N., Vita, R., Defurne, M., Deur, A., Diehl, S., Djalali, C., Duer, M., Dupre, R., Egiyan, H., Mathieu Ehrhart, Alaoui, A. El, Fassi, L. El, Elouadrhiri, L., Eugenio, P., Fegan, S., Fersch, R., Filippi, A., Gavalian, G., Ghandilyan, Y., Gilfoyle, G. P., Girod, F. X., Golubenko, A. A., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hattawy, M., Hayward, T. B., Heddle, D., Hicks, K., Hobart, A., Holtrop, M., Hyde, C. E., Ilieva, Y., Ireland, D. G., Isupov, E. L., Jo, H. S., Joo, K., Joosten, S., Keller, D., Khanal, A., Khandaker, M., Kim, A., Kim, W., Kripko, A., Kubarovsky, V., Lanza, L., Leali, M., Lenisa, P., Livingston, K., Macgregor, I. J. D., Marchand, D., Marsicano, L., Mascagna, V., Mckinnon, B., Migliorati, S., Mirazita, M., Mokeev, V., Camacho, C. Munoz, Nadel-Turonski, P., Neupane, K., Niccolai, S., Niculescu, G., O Connell, T. R., Osipenko, M., Ostrovidov, A. I., Pandey, P., Paolone, M., Pappalardo, L. L., Paremuzyan, R., Pasyuk, E., Pogorelko, O., Pokhrel, M., Poudel, J., Price, J. W., Prok, Y., Raue, B. A., Reed, Trevor, Ripani, M., Ritman, J., Rizzo, A., Rosner, G., Rossi, P., Rowley, J., Sabatié, F., Schumacher, R. A., Segarra, E. P., Sharabian, Y. G., Shirokov, E. V., Shrestha, U., Soto, O., Sparveris, N., Stepanyan, S., Strakovsky, I. I., Strauch, S., Tyson, R., Ungaro, M., Venturelli, L., Voskanyan, H., Vossen, A., Voutier, E., Wei, Kevin, Wei, X., Wishart, R., Wood, M. H., Yale, B., Zachariou, N., Zhang, J., Zhao, Z. W., Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and CLAS

Subjects
ratio, cross section, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Nuclear Theory, scaling, nucleus, scattering, nucleon, FOS: Physical sciences, short-range, momentum, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], missing-energy, Nuclear Theory (nucl-th), kinematics, Fermi surface, measured, Nuclear Experiment (nucl-ex), Nuclear Experiment, deuterium
Abstract

We report the first measurement of $x_B$-scaling in $(e,e'p)$ cross-section ratios off nuclei relative to deuterium at large missing-momentum of $350 \leq p_{miss} \leq 600$ MeV/c. The observed scaling extends over a kinematic range of $0.7 \leq x_B \leq 1.8$, which is significantly wider than $1.4 \leq x_B \leq 1.8$ previously observed for inclusive $(e,e')$ cross-section ratios. The $x_B$-integrated cross-section ratios become constant (i.e., scale) beginning at $p_{miss}\approx k_F$, the nuclear Fermi momentum. Comparing with theoretical calculations we find good agreement with Generalized Contact Formalism calculations for high missing-momentum ($> 375$ MeV/c), suggesting the observed scaling results from interacting with nucleons in short-range correlated (SRC) pairs. For low missing-momenta, mean-field calculations show good agreement with the data for $p_{miss}\le k_F$, and suggest that contributions to the measured cross-section ratios from scattering off single, un-correlated, nucleons are non-negligible up to $p_{miss}\approx 350$ MeV/c. Therefore, SRCs become dominant in nuclei at $p_{miss}\approx 350$ MeV/c, well above the nuclear Fermi Surface of $k_F \approx 250$ MeV/c., 7 pages, 4 figures and supplementary materials

Published
2022

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

Author

Rowley, J., Compton, N., Djalali, C., Hicks, K., Price, J., Zachariou, N., Adhikari, K. P., Armstrong, W. R., Atac, H., Baashen, L., Barion, L., Bashkanov, M., Battaglieri, M., Bedlinskiy, I., Benmokhtar, F., Bianconi, A., Biondo, L., Biselli, A. S., Bondi, M., Bossù, F., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Bulumulla, D., Burkert, V. D., Carman, D. S., Carvajal, J. C., Celentano, A., Chatagnon, P., Chesnokov, V., Chetry, T., Ciullo, G., Clark, Louise, Cole, P. L., Contalbrigo, M., Costantini, G., Crede, V., D’Angelo, A., Dashyan, N., De Vita, R., Defurne, M., Deur, A., Diehl, S., Dupré, R., Egiyan, H., Ehrhart, M., El Alaoui, A., El Fassi, L., Eugenio, P., Fedotov, G., Fegan, S., Fersch, R., Filippi, A., Fradi, A., Gavalian, G., Girod, F. X., Glazier, Derek I., Golubenko, A., Gothe, R. W., Griffioen, K., Guo, L., Hafidi, K., Hakobyan, H., Hattawy, M., Hayward, T. B., Heddle, D., Hobart, A., Holtrop, M., Ilieva, Y., Ireland, David G., Isupov, E. L., Jenkins, D., Jo, H. S., Joo, K., Keller, D., Khanal, A., Khandaker, M., Kim, A., Korover, I., Kripko, A., Kubarovsky, V., Kuhn, S. E., Lanza, L., Leali, M., Lenisa, P., Livingston, Kenneth, MacGregor, I. J. Douglas, Marchand, D., Markov, N., Marsicano, L., Mascagna, V., McCracken, M. E., McKinnon, Bryan, McLauchlin, C., Meziani, Z. E., Migliorati, S., Mineeva, T., Mirazita, M., Mokeev, V., Munevar, E., Munoz Camacho, C., Nadel-Turonski, P., Neupane, K., Niccolai, S., Niculescu, G., O’Connell, T. R., Osipenko, M., Ostrovidov, A. I., Pandey, P., Paolone, M., Pappalardo, L. L., Pasyuk, E., Pogorelko, O., Prok, Y., Reed, T., Ripani, M., Ritman, J., Rizzo, A., Rosner, Guenther, Sabatie, F., Salgado, C., Schmidt, A., Schumacher, R. A., Sharabian, Y. G., Shrestha, U., Sokhan, Daria, Soto, O., Sparveris, N., Strakovsky, I. I., Strauch, S., Tyson, Richard, Ungaro, M., Venturelli, L., Voskanyan, H., Vossen, A., Voutier, E., Watts, D. P., Wei, K., Wei, X., Wishart, Robert, Wood, M. H., Yale, B., Yurov, M., Zhang, J., and Zhao, Z. W.

Subjects
Hyperons in neutron stars, Economica, PE2_2, PE2_1, Settore FIS/04, Nuclear Theory, Socio-culturale, Ambientale, ddc:530, Hyperons's Scattering, Nuclear Experiment, PE2_3
Abstract

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

Published
2021

6. Observation of Beam Spin Asymmetries in the Process ep→e^{'}π^{+}π^{-}X with CLAS12

Author

Hayward, T B, Dilks, C, Vossen, A, Avakian, H, Adhikari, S, Angelini, G, Arratia, M, Atac, H, Ayerbe Gayoso, C, Baltzell, N A, Barion, L, Battaglieri, M, Bedlinskiy, I, Benmokhtar, F, Bianconi, A, Biselli, A S, Bondì, M, Bossù, F, Boiarinov, S, Briscoe, W J, Brooks, W K, Bulumulla, D, Burkert, V D, Carman, D S, Carvajal, J C, Celentano, A, Chatagnon, P, Chetry, T, Ciullo, G, Clary, B A, Cole, P L, Contalbrigo, M, Costantini, G, Crede, V, D'Angelo, A, Dashyan, N, De Vita, R, Defurne, M, Deur, A, Diehl, S, Djalali, C, Dupre, R, Dugger, M, Egiyan, H, Ehrhart, M, El Alaoui, A, El Fassi, L, Elouadrhiri, L, Fegan, S, Filippi, A, Forest, T A, Gavalian, G, Gilfoyle, G P, Girod, F X, Glazier, Derek I., Golubenko, A A, Gothe, R W, Gotra, Y, Griffioen, K A, Guidal, M, Hafidi, K, Hakobyan, H, Hattawy, M, Hauenstein, F, Hicks, K, Hobart, A, Holtrop, M, Ireland, David G., Isupov, E L, Jo, H S, Joo, K, Joosten, S, Keller, D, Khachatryan, M, Khanal, A, Kim, A, Kim, W, Kripko, A, Kubarovsky, V, Kuhn, S E, Lanza, L, Leali, M, Lee, S, Lenisa, P, Livingston, Kenneth, MacGregor, I.D. Douglas, Marchand, D, Markov, N, Marsicano, L, Mascagna, V, McKinnon, Bryan, Meziani, Z E, Mirazita, M, Mokeev, V, Movsisyan, A, Munoz Camacho, C, Nadel-Turonski, P, Naidoo, Paul, Nanda, S, Neupane, K, Niccolai, S, Niculescu, G, O'Connell, T R, Osipenko, M, Paolone, M, Pappalardo, L L, Paremuzyan, R, Pasyuk, E, Phelps, W, Pogorelko, O, Prok, Y, Raue, B A, Ripani, M, Ritman, J, Rizzo, A, Rossi, P, Rowley, J, Sabatié, F, Salgado, C, Schmidt, A, Segarra, E P, Sharabian, Y G, Shrestha, U, Sokhan, Daria, Soto, O, Sparveris, N, Stepanyan, S, Strakovsky, I I, Strauch, S, Thornton, Adam, Tyler, N, Tyson, Richard, Ungaro, M, Venturelli, L, Voskanyan, H, Voutier, E, Watts, D P, Wei, K, Wei, X, Wood, M H, Yale, B, Zachariou, N, Zhang, J, and College of William and Mary [Williamsburg] (WM)

Subjects
[PHYS]Physics [physics], Parton Distribution Functions, Physics, Settore FIS/04, Nuclear Theory, NO, PE2_2, Quantum Chomodynamics, PE2_1, Quarks and Gluons, Physics::Accelerator Physics, High Energy Physics::Experiment, ddc:530, Nuclear Experiment, PE2_3, ComputingMilieux_MISCELLANEOUS
Abstract

The observation of beam spin asymmetries in two-pion production in semi-inclusive deep inelastic scattering off an unpolarized proton target is reported. The data presented here were taken in the fall of 2018 with the CLAS12 spectrometer using a 10.6 GeV longitudinally spin-polarized electron beam delivered by CEBAF at JLab. The measured asymmetries provide the first opportunity to extract the parton distribution function e(x), which provides information about the interaction between gluons and quarks, in a collinear framework that offers cleaner access than previous measurements. The asymmetries also constitute the first ever signal sensitive to the helicity-dependent two-pion fragmentation function G_{1}^{⊥}. A clear sign change is observed around the ρ mass that appears in model calculations and is indicative of the dependence of the produced pions on the helicity of the fragmenting quark.

Published
2021

7. Improved $\Lambda p$ Elastic Scattering Cross Sections Between 0.9 and 2.0 GeV/c and Connections to the Neutron Star Equation of State

Author

CLAS Collaboration, Rowley, J., Compton, N., Djalali, C., Hicks, K., Price, J., Zachariou, N., Adhikari, K. P., Armstrong, W. R., Atac, H., Baashen, L., Barion, L., Bashkanov, M., Battaglieri, M., Bedlinskiy, I., Benmokhtar, F., Bianconi, A., Biondo, L., Biselli, A. S., Bondi, M., Bossu, F., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Bulumulla, D., Burkert, V. D., Carman, D. S., Carvajal, J. C., Celentano, A., Chatagnon, P., Chesnokov, V., Chetry, T., Ciullo, G., Clark, L., Cole, P. L., Contalbrigo, M., Costantini, G., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., Defurne, M., Deur, A., Diehl, S., Dupre, R., Egiyan, H., Ehrhart, M., Alaoui, A. El, Fassi, L. El, Eugenio, P., Fedotov, G., Fegan, S., Fersch, R., Filippi, A., Fradi, A., Gavalian, G., Girod, F. X., Glazier, D. I., Golubenko, A., Gothe, R. W., Griffioen, K., Guo, L., Hafidi, K., Hakobyan, H., Hattawy, M., Hayward, T. B., Heddle, D., Hobart, A., Holtrop, M., Ilieva, Y., Ireland, D. G., Isupov, E. L., Jenkins, D., Jo, H. S., Joo, K., Keller, D., Khanal, A., Khandaker, M., Kim, A., Korover, I., Kripko, A., Kubarovsky, V., Kuhn, S. E., Lanza, L., Leali, M., Lenisa, P., Livingston, K., MacGregor, I. J. D., Marchand, D., Markov, N., Marsicano, L., Mascagna, V., McCracken, M. E., McKinnon, B., McLauchlin, C., Meziani, Z. E., Migliorati, S., Mineeva, T., Mirazita, M., Mokeev, V., Munevar, E., Camacho, C. Munoz, Nadel-Turonski, P., Neupane, K., Niccolai, S., Niculescu, G., O'Connell, T. R., Osipenko, M., Ostrovidov, A. I., Pandey, P., Paolone, M., Pappalardo, L. L., Pasyuk, E., Pogorelko, O., Prok, Y., Reed, T., Ripani, M., Ritman, J., Rizzo, A., Rosner, G., Sabatie, F., Salgado, C., Schmidt, A., Schumacher, R. A., Sharabian, Y. G., Shrestha, U., Sokhan, D., Soto, O., Sparveris, N., Strakovsky, I. I., Strauch, S., Tyson, R., Ungaro, M., Venturelli, L., Voskanyan, H., Vossen, A., Voutier, E., Watts, D., Wei, K., Wei, X., Wishart, R., Wood, M. H., Yale, B., Yurov, M., Zhang, J., Zhao, Z. W., Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and CLAS

Subjects
25.55.Cj E, data analysis method, Nuclear Theory, Newport News CEBAF Linac, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], High Energy Physics - Experiment, kinematics, CLAS, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], 13.75.Ev, ddc:530, cross section: elastic scattering, neutron star, p Lambda: elastic scattering, 13.85.Lg, Nuclear Experiment, nucleus: equation of state, Lambda: momentum, channel cross section: measured, Jefferson Lab, experimental results
Abstract

Physical review letters 127(27), 272303 (2021). doi:10.1103/PhysRevLett.127.272303, Strange matter is believed to exist in the cores of neutron stars based on simple kinematics. If this is true, then hyperon-nucleon interactions will play a significant part in the neutron star equation of state. Yet, compared to other elastic scattering processes, there is very little data on �����N scattering. This experiment utilized the CEBAF Large Acceptance Spectrometer (CLAS) detector to study the ��p�����p elastic scattering cross section in the incident �� momentum range 0.9���2.0 GeV/c. These are the first data on this reaction since the 1970s. The new cross sections have significantly better accuracy and precision than the existing world data, and the techniques developed here can also be used in future experiments., Published by APS, College Park, Md.

Published
2021

8. Improved $��p$ Elastic Scattering Cross Sections Between 0.9 and 2.0 GeV/c and Connections to the Neutron Star Equation of State

Author

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

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

Strange matter is believed to exist in the cores of neutron stars based on simple kinematics. If this is true, then hyperon-nucleon interactions will play a significant part in the neutron star equation of state (EOS). Yet, compared to other elastic scattering processes, there is very little data on $��$-$N$ scattering. This experiment utilized the CLAS detector to study the $��p \rightarrow ��p$ elastic scattering cross section in the incident $��$ momentum range 0.9-2.0 GeV/c. This is the first data on this reaction in several decades. The new cross sections have significantly better accuracy and precision than the existing world data, and the techniques developed here can also be used in future experiments., 6 pages, 5 figures

Published
2021
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9. Observation of Beam Spin Asymmetries in the Process $e p \rightarrow e ��^{+}��^{-}X$ with CLAS12

Author

Hayward, T. B., Dilks, C., Vossen, A., Avakian, H., Adhikari, S., Angelini, G., Arratia, M., Atac, H., Gayoso, C. Ayerbe, Baltzell, N. A., Barion, L., Battaglieri, M., Bedlinskiy, I., Benmokhtar, F., Bianconi, A., Biselli, A. S., Bond��, M., Boss��, F., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Bulumulla, D., Burkert, V. D., Carman, D. S., Carvajal, J. C., Celentano, A., Chatagnon, P., Chetry, T., Ciullo, G., Clary, B. A., Cole, P. L., Contalbrigo, M., Costantini, G., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., Defurne, M., Deur, A., Diehl, S., Djalali, C., Dupre, R., Dugger, M., Egiyan, H., Ehrhart, M., Alaoui, A. El, Fassi, L. El, Elouadrhiri, L., Fegan, S., Filippi, A., Forest, T. A., Gavalian, G., Gilfoyle, G. P., Girod, F. X., Glazier, D. I., Golubenko, A. A., Gothe, R. W., Gotra, Y., Griffioen, K. A., Guidal, M., Hafidi, K., Hakobyan, H., Hattawy, M., Hauenstein, F., Hicks, K., Hobart, A., Holtrop, M., Ireland, D. G., Isupov, E. L., Jo, H. S., Joo, K., Joosten, S., Keller, D., Khachatryan, M., Khanal, A., Kim, A., Kim, W., Kripko, A., Kubarovsky, V., Kuhn, S. E., Lanza, L., Leali, M., Lee, S., Lenisa, P., Livingston, K., MacGregor, I. J. D., Marchand, D., Markov, N., Marsicano, L., Mascagna, V., McKinnon, B., Meziani, Z. E., Mirazita, M., Mokeev, V., Movsisyan, A, Camacho, C. Munoz, Nadel-Turonski, P., Naidoo, P., Nanda, S., Neupane, K., Niccolai, S., Niculescu, G., O'Connell, T. R., Osipenko, M., Paolone, M., Pappalardo, L. L., Paremuzyan, R., Pasyuk, E., Phelps, W., Pogorelko, O., Prok, Y., Raue, B. A., Ripani, M., Ritman, J., Rizzo, A., Rossi, P., Rowley, J., Sabati��, F., Salgado, C., Schmidt, A., Segarra, E. P., Sharabian, Y. G., Shrestha, U., Sokhan, D., Soto, O., Sparveris, N., Stepanyan, S., Strakovsky, I. I., Strauch, S., Thornton, A., Tyler, N., Tyson, R., Ungaro, M., Venturelli, L., Voskanyan, H., Voutier, E., Watts, D. P., Wei, K., Wei, X., Wood, M. H., Yale, B., Zachariou, N., and Zhang, J.

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

The observation of beam spin asymmetries in two-pion production in semi-inclusive deep inelastic scattering off an unpolarized proton target is reported. The data presented here were taken in the fall of 2018 with the CLAS12 spectrometer using a 10.6 GeV longitudinally spin-polarized electron beam delivered by CEBAF at JLab. The measured asymmetries provide the first opportunity to extract the parton distribution function $e(x)$, which provides information about the interaction between gluons and quarks, in a collinear framework that offers cleaner access than previous measurements. The asymmetries also constitute the first ever signal sensitive to the helicity-dependent two-pion fragmentation function $G_1^\perp$. A clear sign change is observed around the $��$ mass that appears in model calculations and is indicative of the dependence of the produced pions on the helicity of the fragmenting quark., 6 pages, 5 figures

Published
2021
Full Text
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10. Observation of Beam Spin Asymmetries in the Process $e p \rightarrow e \pi^{+}\pi^{-}X$ with CLAS12

Author

Hayward, T. B., Dilks, C., Vossen, A., Avakian, H., Adhikari, S., Angelini, G., Arratia, M., Atac, H., Gayoso, C. Ayerbe, Baltzell, N. A., Barion, L., Battaglieri, M., Bedlinskiy, I., Benmokhtar, F., Bianconi, A., Biselli, A. S., Bondì, M., Bossù, F., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Bulumulla, D., Burkert, V. D., Carman, D. S., Carvajal, J. C., Celentano, A., Chatagnon, P., Chetry, T., Ciullo, G., Clary, B. A., Cole, P. L., Contalbrigo, M., Costantini, G., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., Defurne, M., Deur, A., Diehl, S., Djalali, C., Dupre, R., Dugger, M., Egiyan, H., Ehrhart, M., Alaoui, A. El, Fassi, L. El, Elouadrhiri, L., Fegan, S., Filippi, A., Forest, T. A., Gavalian, G., Gilfoyle, G. P., Girod, F. X., Glazier, D. I., Golubenko, A. A., Gothe, R. W., Gotra, Y., Griffioen, K. A., Guidal, M., Hafidi, K., Hakobyan, H., Hattawy, M., Hauenstein, F., Hicks, K., Hobart, A., Holtrop, M., Ireland, D. G., Isupov, E. L., Jo, H. S., Joo, K., Joosten, S., Keller, D., Khachatryan, M., Khanal, A., Kim, A., Kim, W., Kripko, A., Kubarovsky, V., Kuhn, S. E., Lanza, L., Leali, M., Lee, S., Lenisa, P., Livingston, K., MacGregor, I. J. D., Marchand, D., Markov, N., Marsicano, L., Mascagna, V., McKinnon, B., Meziani, Z. E., Mirazita, M., Mokeev, V., Movsisyan, A, Camacho, C. Munoz, Nadel-Turonski, P., Naidoo, P., Nanda, S., Neupane, K., Niccolai, S., Niculescu, G., O'Connell, T. R., Osipenko, M., Paolone, M., Pappalardo, L. L., Paremuzyan, R., Pasyuk, E., Phelps, W., Pogorelko, O., Prok, Y., Raue, B. A., Ripani, M., Ritman, J., Rizzo, A., Rossi, P., Rowley, J., Sabatié, F., Salgado, C., Schmidt, A., Segarra, E. P., Sharabian, Y. G., Shrestha, U., Sokhan, D., Soto, O., Sparveris, N., Stepanyan, S., Strakovsky, I. I., Strauch, S., Thornton, A., Tyler, N., Tyson, R., Ungaro, M., Venturelli, L., Voskanyan, H., Voutier, E., Watts, D. P., Wei, K., Wei, X., Wood, M. H., Yale, B., Zachariou, N., Zhang, J., HEP, INSPIRE, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and CLAS

Subjects
electron p: deep inelastic scattering, [PHYS.HEXP] Physics [physics]/High Energy Physics - Experiment [hep-ex], electron: polarized beam, Nuclear Theory, polarization: longitudinal, parton: distribution function, collinear, helicity: asymmetry: measured, GeV, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Newport News CEBAF Linac, fragmentation function, High Energy Physics - Experiment, quark, p: target, two-pion, CLAS, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], electron: beam, Nuclear Experiment, Nuclear Physics, deep inelastic scattering: semi-inclusive reaction, gluon, Physics::Accelerator Physics, High Energy Physics::Experiment, spectrometer, pi: pair production, spin: asymmetry, Jefferson Lab, experimental results
Abstract

The observation of beam spin asymmetries in two-pion production in semi-inclusive deep inelastic scattering off an unpolarized proton target is reported. The data presented here were taken in the fall of 2018 with the CLAS12 spectrometer using a 10.6 GeV longitudinally spin-polarized electron beam delivered by CEBAF at JLab. The measured asymmetries provide the first opportunity to extract the parton distribution function $e(x)$, which provides information about the interaction between gluons and quarks, in a collinear framework that offers cleaner access than previous measurements. The asymmetries also constitute the first ever signal sensitive to the helicity-dependent two-pion fragmentation function $G_1^\perp$. A clear sign change is observed around the $\rho$ mass that appears in model calculations and is indicative of the dependence of the produced pions on the helicity of the fragmenting quark., Comment: 6 pages, 5 figures

Published
2021

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

Author

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

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

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

Published
2020

12. Modified structure of protons and neutrons in correlated pairs

Author

The CLAS Collaboration, Schmookler, B., Duer, M., Schmidt, A., Hen, O., Gilad, S., Piasetzky, E., Strikman, M., Weinstein, L.B., Adhikari, S., Amaryan, M., Ashkenazi, A., Avakian, H., Ball, J., Balossino, I., Barion, L., Bashkanov, M., Battaglieri, M., Beck, A., Bedlinskiy, I., Biselli, A.S., Boiarinov, S., Briscoe, W.J., Brooks, W.K., Burkert, V.D., Carman, D.S., Celentano, A., Charles, G., Chetry, T., Ciullo, G., Cohen, E., Cole, P.L., Crede, V., Cruz-Torres, R., D'Angelo, A., Dashyan, N., De Sanctis, E., De Vita, R., Deur, A., Diehl, S., Djalali, C., Dupre, R., Egiyan, H., El Fassi, L., Elouadrhiri, L., Eugenio, P., Fedotov, G., Fersch, R., Filippi, A., Forest, T.A., Gavalian, G., Gilfoyle, G.P., Girod, F.X., Golovatch, E., Gothe, R.W., Griffioen, K.A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hauenstein, F., Hayward, T.B., Hicks, K., Higinbotham, D., Holtrop, M., Hyde, C.E., Ilieva, Y., Ireland, D.G., Ishkhanov, B.S., Isupov, E.L., Jo, H.-S., Johnston, S., Joo, K., Joosten, S., Kabir, M.L., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F.J., Korover, I., Kubarovsky, V., Kuhn, S.E., Kuleshov, S.V., Lanza, L., Laskaris, G., Lenisa, P., Livingston, K., MacGregor, I.J.D., Markov, N., McKinnon, B., Mey-Tal Beck, S., Mineeva, T., Mirazita, M., Mokeev, V., Montgomery, R.A., Munoz Camacho, C., Mustapha, B., Niccolai, S., Osipenko, M., Ostrovidov, A.I., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Patsyuk, M., Pogorelko, O., Price, J.W., Prok, Y., Protopopescu, D., Ripani, M., Riser, D., Rizzo, A., Rosner, G., Rossi, P., Sabatié, F., Salgado, C., Schumacher, R.A., Segarra, E.P., Sharabian, Y.G., Skorodumina, I.U., Sokhan, D., Sparveris, N., Stephanyan, S., Strauch, S., Taouti, M., Tan, J.A., Ungaro, M., Voskanyan, H., Voutier, E., Watts, D.P., Wei, X., Wood, M., Zachariou, N., Zhang, J., Zhao, Z.W., and Zheng, X.

Subjects
High Energy Physics::Phenomenology, Nuclear Theory, Nuclear Experiment
Abstract

The atomic nucleus is made of protons and neutrons (nucleons), which are themselves composed of quarks and gluons. Understanding how the quark–gluon structure of a nucleon bound in an atomic nucleus is modified by the surrounding nucleons is an outstanding challenge. Although evidence for such modification—known as the EMC effect—was first observed over 35 years ago, there is still no generally accepted explanation for its cause1,2,3. Recent observations suggest that the EMC effect is related to close-proximity short-range correlated (SRC) nucleon pairs in nuclei4,5. Here we report simultaneous, high-precision measurements of the EMC effect and SRC abundances. We show that EMC data can be explained by a universal modification of the structure of nucleons in neutron–proton SRC pairs and present a data-driven extraction of the corresponding universal modification function. This implies that in heavier nuclei with many more neutrons than protons, each proton is more likely than each neutron to belong to an SRC pair and hence to have distorted quark structure. This universal modification function will be useful for determining the structure of the free neutron and thereby testing quantum chromodynamics symmetry-breaking mechanisms and may help to discriminate between nuclear physics effects and beyond-the-standard-model effects in neutrino experiments.

Published
2019

13. 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, A. V., Klempt, E., Nikonov, V. A., Sarantsev, A. V., Wei, N. C., Huang, F., Nakayama, K., Adhikari, K. P., Adhikari, S., Angelini, G., Avakian, H., Barion, L., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brock, J., Brooks, W. K., Burkert, V. D., Cao, F., Carlin, C., Carman, D. S., Celentano, A., Chatagnon, P., Chetry, T., Ciullo, G., Cole, P. L., 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, G. P., Girod, F. X., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hanretty, C., Harrison, N., Hattawy, M., Hayward, T. B., Heddle, D., Hicks, K., Holtrop, M., Ilieva, Y., Ireland, D.G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jo, H. S., Johnston, S., Joosten, S., Kabir, M. L., Keith, C. D., Keller, D., Khachatryan, G., Khachatryan, M., Khanal, A., Khandaker, M., Kim, A., Kim, W., Klein, F. J., Kubarovsky, V., Kuleshov, S. V., Kunkel, M. C., Lanza, L., Lenisa, P., Livingston, K., MacGregor, I.J.D., Marchand, D., McKinnon, B., Meekins, D. G., Meyer, C. A., Mineeva, T., Mokeev, V., Montgomery, R.A., Movsisyan, A., Munoz Camacho, C., Nadel-Turonski, P., Niccolai, S., Niculescu, G., Osipenko, M., Ostrovidov, A. I., Paolone, M., Pappalardo, L. L., Paremuzyan, R., Pasyuk, E., Payette, D., Phelps, W., Pierce, J., Pogorelko, O., Prok, Y., Protopopescu, D., Raue, B. A., Ripani, M., Riser, D., Ritchie, B. G., Rizzo, A., Rosner, G., Sabatié, F., Salgado, C., Schumacher, R. A., Seely, M. L., Sharabian, Y. G., Shrestha, U., Skorodumina, Iu., Sokhan, D., Soto, O., Sparveris, N., Strakovsky, I. I., Strauch, S., Taiuti, M., Tan, J. A., Torayev, B., Tyler, N., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Wang, R., Watts, D. P., Wei, X., Wood, M. H., Zachariou, N., Zhang, J., Zhao, Z. W., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), CLAS, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112))

Subjects
Nuclear Theory, partial wave, Socio-culturale, nucleon resonance, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], High Energy Physics - Experiment, Photonuclear reactions, Color confinement, Polarization phenomena, QCD in nuclear reactions, Resonance reactions, CLAS, Resonance reactions, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Experiment, Nuclear Physics, Settore FIS/04, Polarization phenomena, photon, nucleon, Photonuclear reactions, Color confinement, Automatic Keywords, transverse, QCD in nuclear reactions, polarization: target, Physics::Accelerator Physics, data management, asymmetry, experimental results, Jefferson Lab, photoproduction
Abstract

First measurements of double-polarization observables in $\omega$ 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 ($N^\ast$) resonances. In particular, contributions from new $N^\ast$ resonances listed in the Review of Particle Properties are observed, which aid in reaching the goal of mapping out the nucleon resonance spectrum., Comment: Two authors added, figures updated

Published
2019

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

Author

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

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

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

Published
2018

15. Center of mass motion of short-range correlated nucleon pairs studied via the A(e,e'pp) reaction

Author

Cohen, E O, Hen, O, Piasetzky, E, Weinstein, L B, Duer, M, Schmidt, A, Korover, I, Hakobyan, H, Adhikari, S, Akbar, Z, Amaryan, M J, Avakian, H, Ball, J, Barion, L, Battaglieri, M, Beck, A, Bedlinskiy, I, Biselli, A S, Boiarinov, S, Briscoe, W, Burkert, V D, Cao, F, Carman, D S, Celentano, A, Charles, G, Chatagnon, Pierre, Chetry, T, Ciullo, G, Clary, Brandon A, 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, Dupre, R, Egiyan, H, Ehrhart, Mathieu, El Alaoui, A, Fassi, L El, Eugenio, P, Fedotov, G, Fersch, R, Filippi, A, Ghandilyan, Y, Giovanetti, K L, Girod, F X, Golovatch, E, Gothe, R W, Griffioen, K A, Hafidi, K, Harrison, N, Hauenstein, F, Heddle, D, Hicks, K, Holtrop, M, Ireland, D.G., Ishkhanov, B S, Isupov, E L, Jenkins, D, Jo, H S, Johnston, S, Kabir, M L, Keller, D, Khachatryan, G, Khachatryan, M, Khandaker, M, Kim, A, Kim, W, Klein, A, Klein, F J, Kubarovsky, V, Kuhn, S E, Lanza, L, Lenisa, P, Livingston, K., MacGregor, I.J.D., Marchand, D, McKinnon, B., Mey-Tal Beck, S, Meyer, C A, Mirazita, M, Mokeev, V, Montgomery, R.A., Movsisyan, A, Munoz Camacho, C, Mustapha, B, Nadel-Turonski, P, Niccolai, S, Niculescu, G, Osipenko, M, Ostrovidov, A I, Paolone, M, Paremuzyan, R, Pasyuk, E, Pogorelko, O, Price, J W, Prok, Y, Protopopescu, D., Ripani, M, Riser, D, Rizzo, A, Rosner, G., Rossi, P, Sabatié, F, Schmookler, B A, Schumacher, R A, Sharabian, Y G, Sokhan, D., Sparveris, N, Stepanyan, S, Strauch, S, Taiuti, M, Tan, J A, Ungaro, M, Voskanyan, H, Voutier, E, Wang, R, Watts, D P, Wei, X, Wood, M H, Zachariou, N, Zhang, J, Zheng, X, and Zhao, Z W

Subjects
Nuclear Theory, Nuclear Experiment
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

16. First measurement of Xi(-) polarization in photoproduction

Author

Bono, J., Guo, L., Raue, B. A., Adhikari, S., Kunkel, M. C., Adhikari, K. P., Akbar, Z., Amaryan, M. J., Barion, L., Bashkanov, M., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Burkert, V. D., Cao, F., Carman, D. S., Celentano, A., Charles, G., Chetry, T., Ciullo, G., Clary, Brandon A., Cole, P. L., Contalbrigo, M., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., Defurne, M., Deur, A., Diehl, S., Djalali, C., Dugger, M., Egiyan, H., El Alaoui, A., El Fassi, L., Eugenio, P., Fedotov, G., Filippi, A., Fradi, A., Gavalian, G., Gevorgyan, N., Ghandilyan, Y., Girod, F. X., Glazier, D. I., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Hafidi, K., Harrison, N., Hattawy, M., Heddle, D., Hicks, K., Holtrop, M., Ilieva, Y., Ireland, D. G., Isupov, E. L., Jo, H. S., Johnston, S., Kabir, M. L., Keller, D., Khachatryan, G., Khachatryan, M., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Lenisa, P., Livingston, K., MacGregor, I. J.D., Markov, N., McKinnon, B., Mineeva, T., Montgomery, R. A., Munoz Camacho, C., Niculescu, G., Osipenko, M., Ostrovidov, A. I., Paolone, M., Paremuzyan, R., Park, K., Pasyuk, E., Phelps, W., Pogorelko, O., Price, J. W., Prok, Y., Protopopescu, D., Ripani, M., Rizzo, A., Rosner, G., Sabatié, F., Salgado, C., Schumacher, R. A., Sharabian, Y., Skorodumina, Iu, Sokhan, D., Sparveris, N., Stepanyan, S., Strakovsky, I. I., Strauch, S., Taiuti, M., Ungaro, M., Voskanyan, H., Voutier, E., Zachariou, N., Zana, L., and Zhao, Z. W.

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

Despite decades of studies of the photoproduction of hyperons, both their production mechanisms and their spectra of excited states are still largely unknown. While the parity-violating weak decay of hyperons offers a means of measuring their polarization, which could help discern their production mechanisms and identify their excitation spectra, no such study has been possible for doubly strange baryons in photoproduction, due to low production cross sections. However, by making use of the reaction γp→K+K+Ξ−, we have measured, for the first time, the induced polarization, P, and the transferred polarization from circularly polarized real photons, characterized by Cx and Cz, to recoiling Ξ−s. The data were obtained using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab for photon energies from just over threshold (2.4 GeV) to 5.45 GeV. These first-time measurements are compared, and are shown to broadly agree, with model predictions in which cascade photoproduction proceeds through the decay of intermediate hyperon resonances that are produced via relativistic meson exchange, offering a new step forward in the understanding of the production and polarization of doubly-strange baryons.

Published
2018

17. First Measurements of the Double-Polarization Observables $F$, $P$, and $H$ in $��$ Photoproduction off Transversely Polarized Protons in the $N^\ast$ Resonance Region

Author

Roy, P., Park, S., Crede, V., Anisovich, A. V., Klempt, E., Nikonov, V. A., Sarantsev, A. V., Wei, N. C., Huang, F., Nakayama, K., Adhikari, K. P., Adhikari, S., Angelini, G., Avakian, H., Barion, L., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brock, J., Brooks, W. K., Burkert, V. D., Cao, F., Carlin, C., Carman, D. S., Celentano, A., Chatagnon, P., Chetry, T., Ciullo, G., Cole, P. L., 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., Alaoui, A. El, Fassi, L. El, Eugenio, P., Fegan, S., Filippi, A., Fradi, A., Gilfoyle, G. P., Girod, F. X., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hanretty, C., Harrison, N., Hattawy, M., Hayward, T. B., Heddle, D., Hicks, K., Holtrop, M., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jo, H. S., Johnston, S., Joosten, S., Kabir, M. L., Keith, C. D., Keller, D., Khachatryan, G., Khachatryan, M., Khanal, A., Khandaker, M., Kim, A., Kim, W., Klein, F. J., Kubarovsky, V., Kuleshov, S. V., Kunkel, M. C., Lanza, L., Lenisa, P., Livingston, K., MacGregor, I. J. D., Marchand, D., McKinnon, B., Meekins, D. G., Meyer, C. A., Mineeva, T., Mokeev, V., Montgomery, R. A., Movsisyan, A, Camacho, C. Munoz, Nadel-Turonski, P., Niccolai, S., Niculescu, G., Osipenko, M., Ostrovidov, A. I., Paolone, M., Pappalardo, L. L., Paremuzyan, R., Pasyuk, E., Payette, D., Phelps, W., Pierce, J., Pogorelko, O., Prok, Y., Protopopescu, D., Raue, B. A., Ripani, M., Riser, D., Ritchie, B. G., Rizzo, A., Rosner, G., Sabatie, F., Salgado, C., Schumacher, R. A., Seely, M. L., Sharabian, Y. G., Shrestha, U., Skorodumina, Iu., Sokhan, D., Soto, O., Sparveris, N., Strakovsky, I. I., Strauch, S., Taiuti, M., Tan, J. A., Torayev, B., Tyler, N., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Wang, R., Watts, D. P., Wei, X., Wood, M. H., Zachariou, N., Zhang, J., and Zhao, Z. W.

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

First measurements of double-polarization observables in $��$ 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 ($N^\ast$) resonances. In particular, contributions from new $N^\ast$ resonances listed in the Review of Particle Properties are observed, which aid in reaching the goal of mapping out the nucleon resonance spectrum., Two authors added, figures updated

Published
2018
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18. Beam-Target Helicity Asymmetry $E$ in $K^{0}��$ and $K^{0}��^0$ Photoproduction on the Neutron

Author

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

Subjects
Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

We report the first measurements of the $E$ beam-target helicity asymmetry for the $\vec�� \vec{n} \to K^{0}��$, and $K^{0}��^{0}$ channels in the energy range 1.70$\leq W\leq$2.34 GeV. The CLAS system at Jefferson Lab uses a circularly polarized photon beam and a target consisting of longitudinally polarized solid molecular hydrogen deuteride with low background contamination for the measurements. The multivariate analysis method boosted decision trees was used to isolate the reactions of interest. Comparisons with predictions from the KaonMAID, SAID, and Bonn-Gatchina models are presented. These results will help separate the isospin $I=0$ and $I=1$ photo-coupling transition amplitudes in pseudoscalar meson photoproduction., 14 pages, 9 figures; Revised to match published version

Published
2018
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19. Target and Beam-Target Spin Asymmetries in Exclusive $��^+$ and $��^-$ Electroproduction with 1.6 to 5.7 GeV Electrons

Author

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

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

Beam-target double spin asymmetries and target single-spin asymmetries in exclusive $��^+$ and $��^-$ electroproduction were obtained from scattering of 1.6 to 5.7 GeV longitudinally polarized electrons from longitudinally polarized protons (for $��^+$) and deuterons (for $��^-$) using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The kinematic range covered is $1.11.5$ GeV. Very large target-spin asymmetries are observed for $W>1.6$ GeV. When combined with cross section measurements, the present results will provide powerful constraints on nucleon resonance amplitudes at moderate and large values of $Q^2$, for resonances with masses as high as 2.3 GeV., 47 pages, 24 figures. This is a revised version that was accepted for publication in Phys. Rev. C. in early October, 2016

Published
2016
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20. First measurement of the polarization observable E in the View the MathML sourcep→(γ→,π+)n reaction up to 2.25 GeV

Author

Strauch, S., Briscoe, W. J., Döring, M., Klempt, E., Nikonov, V. A., Pasyuk, E., Rönchen, D., Sarantsev, A. V., Strakovsky, I., Workman, R., Adhikari, K. P., Adikaram, D., Anderson, M. D., Pereira, S. Anefalos, Anisovich, A. V., Badui, R. A., Ball, J., Batourine, V., Battaglieri, M., Bedlinskiy, I., Benmouna, N., Biselli, A. S., Brock, J., Brooks, W. K., Burkert, V. D., Cao, T., Carlin, C., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Colaneri, L., Cole, P. L., Compton, N., Contalbrigo, M., Cortes, O., Crede, V., Dashyan, N., d'Angelo, A., de Vita, R., de Sanctis, E., Deur, A., Djalali, C., Dugger, M., Dupre, R., Egiyan, H., Alaoui, A. El, Fassi, L. El, Elouadrhiri, L., Eugenio, P., Fedotov, G., Fegan, S., Filippi, A., Fleming, J. A., Forest, T. A., Fradi, A., Gevorgyan, N., Ghandilyan, Y., Giovanetti, K. L., Girod, F. X., Glazier, D. I., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Hicks, K., Ho, D., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jiang, H., Jo, H. S., Joo, K., Joosten, S., Keith, C. D., Keller, D., Khachatryan, G., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Kuhn, S. E., Lenisa, P., Livingston, K., Lu, H. Y., Macgregor, I . J . D., Markov, N., Mckinnon, B., Meekins, D. G., Meyer, C. A., Mokeev, V., Montgomery, R. A., Moody, C. I., Moutarde, H., Movsisyan, A, Munevar, E., Muñoz Camacho, C., Nadel-Turonski, P., Net, L. A., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Park, K., Peng, P., Phelps, W., Phillips, J. J., Pisano, S., Pogorelko, O., Pozdniakov, S., Price, J. W., Procureur, S., Prok, Y., Protopopescu, D., Puckett, A. J. R., Raue, B. A., Ripani, M., Ritchie, B. G., Rizzo, A., Rosner, G., Roy, Pascal, Sabatié, F., Salgado, C., Schott, D., Schumacher, R. A., Seder, E., Seely, M. L., Senderovich, I, Sharabian, Y. G., Simonyan, A., Skorodumina, Iu., Smith, G. D., Sober, D. I., Sokhan, D., Sparveris, N., Stoler, P., Stepanyan, S., Sytnik, V., Taiuti, M., Tian, Ye, Trivedi, A., Tucker, R., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D. P., Wei, X., Wood, M. H., Zachariou, N., Zana, L., Zhang, J., Zhao, Z. W., Zonta, I., Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), CLAS Collaboration, and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear Theory, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract

6 pages, 3 figures; International audience; First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction $\vec \gamma \vec p \to \pi^+n$, has been measured using a circularly polarized tagged-photon beam, with energies from 0.35 to 2.37 GeV. The final-state pions were detected with the CEBAF Large Acceptance Spectrometer in Hall B at the Thomas Jefferson National Accelerator Facility. These polarization data agree fairly well with previous partial-wave analyses at low photon energies. Over much of the covered energy range, however, significant deviations are observed, particularly in the high-energy region where high-L multipoles contribute. The data have been included in new multipole analyses resulting in updated nucleon resonance parameters. We report updated fits from the Bonn-Gatchina, J\"ulich, and SAID groups.

Published
2015

21. First Measurement of the Polarization Observable E in the $\vec p(\vec \gamma,\pi^+)n$ Reaction up to 2.25 GeV

Author

Strauch, S., Briscoe, W. J., Döring, M., Klempt, E., Nikonov, V. A., Pasyuk, E., Rönchen, D., Sarantsev, A. V., Strakovsky, I., Workman, R., Adhikari, K. P., Adikaram, D., Anderson, M. D., Pereira, S. Anefalos, Anisovich, A. V., Badui, R. A., Ball, J., Batourine, V., Battaglieri, M., Bedlinskiy, I., Benmouna, N., Biselli, A. S., Brock, J., Brooks, W. K., Burkert, V. D., Cao, T., Carlin, C., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Colaneri, L., Cole, P. L., Compton, N., Contalbrigo, M., Cortes, O., Crede, V., Dashyan, N., D'Angelo, A., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Dugger, M., Dupre, R., Egiyan, H., Alaoui, A. El, Fassi, L. El, Elouadrhiri, L., Eugenio, P., Fedotov, G., Fegan, S., Filippi, A., Fleming, J. A., Forest, T. A., Fradi, A., Gevorgyan, N., Ghandilyan, Y., Giovanetti, K. L., Girod, F. X., Glazier, D. I., Gohn, W., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Hicks, K., Ho, D., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jiang, H., Jo, H. S., Joo, K., Joosten, S., Keith, C. D., Keller, D., Khachatryan, G., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Kuhn, S. E., Lenisa, P., Livingston, K., Lu, H. Y., MacGregor, I . J . D., Markov, N., McKinnon, B., Meekins, D. G., Meyer, C. A., Mokeev, V., Montgomery, R. A., Moody, C. I., Moutarde, H., Movsisyan, A, Munevar, E., Camacho, C. Munoz, Nadel-Turonski, P., Net, L. A., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Park, K., Peng, P., Phelps, W., Phillips, J. J., Pisano, S., Pogorelko, O., Pozdniakov, S., Price, J. W., Procureur, S., Prok, Y., Protopopescu, D., Puckett, A. J. R., Raue, B. A., Ripani, M., Ritchie, B. G., Rizzo, A., Rosner, G., Roy, P., Sabatié, F., Salgado, C., Schott, D., Schumacher, R. A., Seder, E., Seely, M. L., Senderovich, I, Sharabian, Y. G., Simonyan, A., Skorodumina, Iu., Smith, G. D., Sober, D. I., Sokhan, D., Sparveris, N., Stoler, P., Stepanyan, S., Sytnik, V., Taiuti, M., Tian, Ye, Trivedi, A., Tucker, R., Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D. P., Wei, X., Wood, M. H., Zachariou, N., Zana, L., Zhang, J., Zhao, Z. W., and Zonta, I.

Subjects
Nuclear Theory, Nuclear Experiment, High Energy Physics - Experiment
Abstract

First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction $\vec \gamma \vec p \to \pi^+n$, has been measured using a circularly polarized tagged-photon beam, with energies from 0.35 to 2.37 GeV. The final-state pions were detected with the CEBAF Large Acceptance Spectrometer in Hall B at the Thomas Jefferson National Accelerator Facility. These polarization data agree fairly well with previous partial-wave analyses at low photon energies. Over much of the covered energy range, however, significant deviations are observed, particularly in the high-energy region where high-L multipoles contribute. The data have been included in new multipole analyses resulting in updated nucleon resonance parameters. We report updated fits from the Bonn-Gatchina, J\"ulich, and SAID groups., Comment: 6 pages, 3 figures

Published
2015

22. A search for baryon- and lepton-number violating decays of $��$ hyperons using the CLAS detector at Jefferson Laboratory

Author

McCracken, M. E., Bellis, M., Adhikari, K. P., Adikaram, D., Akbar, Z., Pereira, S. Anefalos, Badui, R. A., Ball, J., Baltzell, N. A., Battaglieri, M., Batourine, V., Bedlinskiy, I., Biselli, A. S., Boiarinov, S., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Cao, T., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Colaneri, L., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Dodge, G. E., Dupre, R., Alaoui, A. El, Fassi, L. El, Elouadrhiri, E., Eugenio, P., Fedotov, G., Fegan, S., Fersch, R., Filippi, A., Fleming, J. A., Garillon, B., Gevorgyan, N., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Golovatch, E., Gothe, R. W., Griffioen, K. A., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Hattawy, M., Hicks, K., Holtrop, M., Hughes, S. M., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Isupov, E. L., Jenkins, D., Jiang, H., Jo, H. S., Keller, D., Khachatryan, G., Khandaker, M., Kim, A., Kim, W., Klein, A., Klein, F. J., Kubarovsky, V., Lenisa, P., Livingston, K., Lu, H. Y., MacGregor, I. J. D., Mayer, M., McKinnon, B., Mestayer, M. D., Meyer, C. A., Mirazita, M., Mokeev, V., Moody, C. I., Moriya, K., Camacho, C. Munoz, Nadel-Turonski, P., Net, L. A., Niccolai, S., Osipenko, M., Ostrovidov, A. I., Park, K., Pasyuk, E., Pisano, S., Pogorelko, O., Price, J. W., Procureur, S., Prok, Y., Raue, B. A., Ripani, M., Rizzo, A., Rosner, G., Roy, P., Sabati��, F., Salgado, C., Schumacher, R. A., Seder, E., Sharabian, Y. G., Skorodumina, Iu., Sokhan, D., Sparveris, N., Stoler, P., Strakovsky, I. I., Strauch, S., Sytnik, V., Tian, Ye, Ungaro, M., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D. P., Wei, X., Wood, M. H., Zachariou, N., Zana, L., Zhang, J., Zhao, Z. W., and Zonta, I.

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

We present a search for ten baryon-number violating decay modes of $��$ hyperons using the CLAS detector at Jefferson Laboratory. Nine of these decay modes result in a single meson and single lepton in the final state ($��\rightarrow m \ell$) and conserve either the sum or the difference of baryon and lepton number ($B \pm L$). The tenth decay mode ($��\rightarrow \bar{p}��^+$) represents a difference in baryon number of two units and no difference in lepton number. We observe no significant signal and set upper limits on the branching fractions of these reactions in the range $(4-200)\times 10^{-7}$ at the $90\%$ confidence level., 12 pages, 7 figures (color)

Published
2015
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23. Measurement of the structure function of the nearly free neutron using spectator tagging in inelastic H2(e,e′ps)X scattering with CLAS

Author

Tkachenko, S., Baillie, N., Kuhn, S. E., Zhang, J., Arrington, J., Bosted, P., B��ltmann, S., Christy, M. E., Dutta, D., Ent, R., Fenker, H., Griffioen, K. A., Ispiryan, M., Kalantarians, N., Keppel, C. E., Melnitchouk, W., Tvaskis, V., Adhikari, K. P., Aghasyan, M., Amaryan, M. J., Pereira, S. Anefalos, Avakian, H., Ball, J., Baltzell, N. A., Battaglieri, M., Bedlinskiy, I., Biselli, A. S., Briscoe, W. J., Brooks, W. K., Burkert, V. D., Carman, D. S., Celentano, A., Chandavar, S., Charles, G., Cole, P. L., Contalbrigo, M., Cortes, O., Crede, V., D'Angelo, A., Dashyan, N., De Vita, R., De Sanctis, E., Deur, A., Djalali, C., Dodge, G. E., Doughty, D., Dupre, R., Egiyan, H., Alaoui, A. El, Fassi, L. El, Elouadrhiri, L., Eugenio, P., Fedotov, G., Fleming, J. A., Garillon, B., Gevorgyan, N., Ghandilyan, Y., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Goetz, J. T., Golovatch, E., Gothe, R. W., Guidal, M., Guo, L., Hafidi, K., Hakobyan, H., Hanretty, C., Harrison, N., Hattawy, M., Hicks, K., Ho, D., Holtrop, M., Hyde, C . E., Ilieva, Y., Ireland, D. G., Ishkhanov, B. S., Jo, H. S., Keller, D., Khandaker, M., Kim, A., Kim, W., King, P. M., Klein, A., Klein, F. J., Koirala, S., Kubarovsky, V., Kuleshov, S. V., Lenisa, P., Lewis, S., Livingston, K., Lu, H., MacCormick, M., MacGregor, I. J. D., Markov, N., Mayer, M., McKinnon, B., Mineeva, T., Mirazita, M., Mokeev, V., Montgomery, R. A., Moutarde, H., Camacho, C. Munoz, Nadel-Turonski, P., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Pappalardo, L. L., Paremuzyan, R., Park, K., Pasyuk, E., Phillips, J. J., Pisano, S., Pogorelko, O., Pozdniakov, S., Price, J. W., Procureur, S., Protopopescu, D., Puckett, A. J . R., Rimal, D., Ripani, M., Rizzo, A., Rosner, G., Rossi, P., Roy, P., Sabati��, F., Schott, D., Schumacher, R. A., Seder, E., Senderovich, I., Sharabian, Y. G., Simonyan, A., Smith, G. D., Sober, D. I., Sokhan, D., Stepanyan, S., Stepanyan, S. S., Strauch, S., Tang, W., Ungaro, M., Vlassov, A. V., Voskanyan, H., Voutier, E., Walford, N. K., Watts, D., Wei, X., Weinstein, L. B., Wood, M. H., Zana, L., Zonta, I., Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), CLAS, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)

Subjects
Nuclear Theory, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment (nucl-ex), Nuclear Experiment, nucl-ex
Abstract

Much less is known about neutron structure than that of the proton due to the absence of free neutron targets. Neutron information is usually extracted from data on nuclear targets such as deuterium, requiring corrections for nuclear binding and nucleon off-shell effects. These corrections are model dependent and have significant uncertainties, especially for large values of the Bjorken scaling variable x. The Barely Off-shell Nucleon Structure (BONuS) experiment at Jefferson Lab measured the inelastic electron deuteron scattering cross section, tagging spectator protons in coincidence with the scattered electrons. This method reduces nuclear binding uncertainties significantly and has allowed for the first time a (nearly) model independent extraction of the neutron structure function. A novel compact radial time projection chamber was built to detect protons with momentum between 70 and 150 MeV/c. For the extraction of the free neutron structure function $F_{2n}$, spectator protons at backward angle and with momenta below 100 MeV/c were selected, ensuring that the scattering took place on a nearly free neutron. The scattered electrons were detected with Jefferson Lab's CLAS spectrometer. The extracted neutron structure function $F_{2n}$ and its ratio to the deuteron structure function $F_{2d}$ are presented in both the resonance and deep inelastic regions. The dependence of the cross section on the spectator proton momentum and angle is investigated, and tests of the spectator mechanism for different kinematics are performed. Our data set can be used to study neutron resonance excitations, test quark hadron duality in the neutron, develop more precise parametrizations of structure functions, as well as investigate binding effects (including possible mechanisms for the nuclear EMC effect) and provide a first glimpse of the asymptotic behavior of d/u as x goes to 1., 28 pages, 22 figures; published in Phys. Rev. C. Revised to include three authors inadvertently left off the original version: D. Dutta, R. Ent, and M. Ispiryan

Published
2014

24. Transverse polarization of $��$ hyperons from quasireal photoproduction on nuclei

Author

The HERMES Collaboration, Airapetian, A., Akopov, N., Akopov, Z., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetisyan, E., Belostotski, S., Bianchi, N., Blok, H. P., Borissov, A., Bowles, J., Brodski, I., Bryzgalov, V., Burns, J., Capiluppi, M., Capitani, G. P., Cisbani, E., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Diefenthaler, M., Di Nezza, P., D��ren, M., Ehrenfried, M., Elbakian, G., Ellinghaus, F., Fabbri, R., Fantoni, A., Felawka, L., Frullani, S., Gabbert, D., Gapienko, G., Gapienko, V., Garibaldi, F., Gavrilov, G., Gharibyan, V., Giordano, F., Gliske, S., Golembiovskaya, M., Hadjidakis, C., Hartig, M., Hasch, D., Hillenbrand, A., Hoek, M., Holler, Y., Hristova, I., Imazu, Y., Ivanilov, A., Jackson, H. E., Jo, H. S., Joosten, S., Kaiser, R., Karyan, G., Keri, T., Kinney, E., Kisselev, A., Kobayashi, N., Korotkov, V., Kozlov, V., Kravchenko, P., Krivokhijine, V. G., Lagamba, L., Lapik��s, L., Lehmann, I., Lenisa, P., Ruiz, A. L��pez, Lorenzon, W., Lu, X. -G., Ma, B. -Q., Mahon, D., Makins, N. C. R., Manaenkov, S. I., Mao, Y., Marianski, B., de la Ossa, A. Martinez, Marukyan, H., Miller, C. A., Miyachi, Y., Movsisyan, A., Muccifora, V., Murray, M., Mussgiller, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. -D., Pappalardo, L. L., Perez-Benito, R., Reimer, P. E., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanftl, F., Sch��fer, A., Schnell, G., Sch��ler, K. P., Seitz, B., Shibata, T. -A., Shutov, V., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stewart, J., Stinzing, F., Taroian, S., Terkulov, A., Truty, R., Trzcinski, A., Tytgat, M., Vandenbroucke, A., Van Haarlem, Y., Van Hulse, C., Veretennikov, D., Vikhrov, V., Vilardi, I., Wang, S., Yaschenko, S., Ye, Z., Yu, W., Zagrebelnyy, V., Zeiler, D., Zihlmann, B., and Zupranski, P.

Subjects
High Energy Physics - Experiment (hep-ex), High Energy Physics::Phenomenology, Nuclear Theory, Physics::Atomic and Molecular Clusters, FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

The transverse polarization of $��$ hyperons was measured in inclusive quasireal photoproduction for various target nuclei ranging from hydrogen to xenon. The data were obtained by the HERMES experiment at HERA using the 27.6 GeV lepton beam and nuclear gas targets internal to the lepton storage ring. The polarization observed is positive for light target nuclei and is compatible with zero for krypton and xenon., final version to be published in Phys. Rev. D (in press)

Published
2014
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25. Transverse Polarization of $��^{+}(1189)$ in Photoproduction on a Hydrogen Target in CLAS

Author

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

Subjects
Nuclear Theory, FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

Experimental results on the $��^+(1189)$ hyperon transverse polarization in photoproduction on a hydrogen target using the CLAS detector at Jefferson laboratory are presented. The $��^+(1189)$ was reconstructed in the exclusive reaction $��+p\rightarrow K^{0}_{S} + ��^+(1189)$ via the $��^{+} \to p ��^{0}$ decay mode. The $K^{0}_S$ was reconstructed in the invariant mass of two oppositely charged pions with the $��^0$ identified in the missing mass of the detected $p��^+��^-$ final state. Experimental data were collected in the photon energy range $E_��$ = 1.0-3.5 GeV ($\sqrt{s}$ range 1.66-2.73 GeV). We observe a large negative polarization of up to 95%. As the mechanism of transverse polarization of hyperons produced in unpolarized photoproduction experiments is still not well understood, these results will help to distinguish between different theoretical models on hyperon production and provide valuable information for the searches of missing baryon resonances., pages 11

Published
2013
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26. Precise Measurements of Beam Spin Asymmetries in Semi-Inclusive $��^0$ production

Author

Aghasyan, M., Avakian, H., Rossi, P., De Sanctis, E., Hasch, D., Mirazita, M., Adikaram, D., Amaryan, M. J., Anghinolfi, M., Baghdasaryan, H., Ball, J., Battaglieri, M., Batourine, V., Bedlinskiy, I., Bennett, R. P., Biselli, A. S., Branford, D., Briscoe, W. J., B��ltmann, S., Burkert, V. D., Carman, D. S., Chandavar, S., Cole, P. L., Collins, P., Contalbrigo, M., Crede, V., D'Angelo, A., Daniel, A., Dashyan, N., De Vita, R., Deur, A., Dey, B., Dickson, R., Djalali, C., Dodge, G. E., Doughty, D., Dupre, R., Egiyan, H., Alaoui, A. El, Elouadrhiri, L., Eugenio, P., Fedotov, G., Fegan, S., Fradi, A., Gabrielyan, M. Y., Gar��on, M., Gevorgyan, N., Gilfoyle, G. P., Giovanetti, K. L., Girod, F. X., Goetz, J. T., Gohn, W., Golovatch, E., Gothe, R. W., Graham, L., Griffioen, K. A., Guegan, B., Guidal, M., Guler, N., Guo, L., Hafidi, K., Hanretty, C., Hicks, K., Holtrop, M., Hyde, C. E., Ilieva, Y., Ireland, D. G., Isupov, E. L., Jawalkar, S. S., Jenkins, D., Jo, H. S., Joo, K., Keller, D., Khandaker, M., Khetarpal, P., Kim, A., Kimy, W., Klein, A., Klein, F. J., Kubarovsky, V., Kuhn, S. E., Kuleshov, S. V., Kuznetsov, V., Kvaltine, N. D., Livingston, K., Lu, H. Y., MacGregor, I . J . D., Markov, N., Mayer, M., McAndrew, J., McKinnon, B., Meyer, C. A., Micherdzinska, A. M., Mokeev, V., Moreno, B., Moutarde, H., Munevar, E., Nadel-Turonski, P., Ni, A., Niccolai, S., Niculescu, G., Niculescu, I., Osipenko, M., Ostrovidov, A. I., Paolone, M., Pappalardo, L., Paremuzyan, R., Park, K., Park, S., Pasyuk, E., Pereira, S. Anefalos, Phelps, E., Pisano, S., Pogorelko, O., Pozdniakov, S., Price, J. W., Procureur, S., Prok, Y., Protopopescu, D., Raue, B. A., Ricco, G., Rimal, D., Ripani, M., Rosner, G., Sabati��, F., Saini, M. S., Salgado, C., Schott, D., Schumacher, R. A., Seder, E., Seraydaryan, H., Sharabian, Y. G., Smith, G. D., Sober, D. I., Stepanyan, S. S., Stepanyan, S., Stoler, P., Strakovsky, I., Strauch, S., Taiuti, M., Tang, W., Taylor, C. E., Tkachenko, S., Ungaro, M., Voskanyan, H., Voutier, E., Watts, D., Weinstein, L. B., Weygand, D. P., Wood, M. H., Zana, L., Zhang, J., Zhao, B., and Zhao, Z. W.

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

We present studies of single-spin asymmetries for neutral pion electroproduction in semi-inclusive deep-inelastic scattering of 5.776 GeV polarized electrons from an unpolarized hydrogen target, using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. A substantial $\sin ��_h$ amplitude has been measured in the distribution of the cross section asymmetry as a function of the azimuthal angle $��_h$ of the produced neutral pion. The dependence of this amplitude on Bjorken $x$ and on the pion transverse momentum is extracted with significantly higher precision than previous data and is compared to model calculations., to be submitted PLB

Published
2011
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27. Measurement of charged-pion production in deep-inelastic scattering off nuclei with the CLAS detector

Author

Morán, S., Dupre, R., Hakobyan, H., Arratia, M., Brooks, W. K., Bórquez, A., Alaoui, A. El, Fassi, L. El, Hafidi, K., Mendez, R., Mineeva, T., Paul, S. J., Amaryan, M. J., Angelini, Giovanni, Armstrong, Whitney R., Atac, H., Baltzell, N. A., Barion, L., Bashkanov, M., Battaglieri, M., Bedlinskiy, I., Benmokhtar, Fatiha, Bianconi, A., Biondo, L., Biselli, A. S., Bossù, F., Boiarinov, S., Briscoe, W. J., Bulumulla, D., Burkert, V. D., Carman, D. S., Chatagnon, P., Chesnokov, V., Chetry, T., Ciullo, G., Cole, P. L., Contalbrigo, M., Costantini, G., D'Angelo, A., Dashyan, N., De Vita, R., Defurne, M., Deur, A., Diehl, S., Djalali, C., Egiyan, H., Elouadrhiri, L., Eugenio, P., Fersch, R., Filippi, A., Gavalian, G., Ghandilyan, Y., Gilfoyle, G. P., Golubenko, A. A., Gothe, R. W., Griffioen, K. A., Guidal, M., Hattawy, M., Hauenstein, F., Hayward, T. B., Heddle, D., Hicks, K., Hobart, A., Holtrop, M., Ilieva, Y., Ireland, D. G., Isupov, E. L., Jo, H. S., Keller, D., Khanal, A., Khandaker, M., Kim, W., Klein, F. J., Kripko, A., Kubarovsky, V., Kuhn, S. E., Lanza, L., Leali, M., Lenisa, P., Livingston, K., MacGregor, I. J. D., Marchand, D., Marsicano, L., Mascagna, V., McKinnon, B., McLauchlin, C., Meziani, Z. E., Migliorati, S., Mirazita, M., Mokeev, V., Camacho, C. Munoz, Nadel-Turonski, P., Neupane, K., Niccolai, S., Niculescu, G., O'Connell, T. R., Osipenko, M., Ostrovidov, A. I., Ouillon, M., Pandey, P., Paolone, M., Pappalardo, L. L., Pasyuk, E., Phelps, W., Pogorelko, O., Poudel, J., Price, J. W., Prok, Y., Raue, B. A., Reed, Trevor, Ripani, M., Ritman, J., Rizzo, A., Rosner, G., Rowley, J., Sabatié, F., Salgado, C., Schmidt, A., Schumacher, R. A., Sharabian, Y. G., Shirokov, E. V., Shrestha, U., Sokhan, D., Soto, O., Sparveris, N., Stepanyan, S., Strakovsky, I. I., Strauch, S., Tyson, R., Ungaro, M., Venturelli, L., Voskanyan, H., Vossen, A., Voutier, E., Watts, D. P., Wei, Kevin, Wei, X., Weinstein, L. B., Wishart, R., Wood, M. H., Yale, B., Zachariou, N., Zhang, J., Zhao, Z. W., Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and CLAS

Subjects
Electron-nucleon Scattering, dimension: 3, Nuclear Theory, Socio-culturale, FOS: Physical sciences, gluon: bremsstrahlung, pi: production, Newport News CEBAF Linac, transverse momentum, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Structure, model: parton, Computer Science::Digital Libraries, fragmentation function, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), Economica, PE2_2, PE2_1, CLAS, transport theory, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], ddc:530, Nuclear Experiment (nucl-ex), electron: beam, quark: energy loss, Nuclear Experiment, PE2_3, pi: energy, deep inelastic scattering: semi-inclusive reaction, multiplicity: ratio, Settore FIS/04, Deep Inelastic Scattering, Ambientale, multiplicity: dependence, QCD, flavor: dependence, hadron: formation, kinematics, nuclear matter, fractional, Quarks and Gluons, High Energy Physics::Experiment, hadronization, experimental results
Abstract

Background: Energetic quarks in nuclear DIS propagate through the nuclear medium. Processes that are believed to occur inside nuclei include quark energy loss through medium-stimulated gluon bremsstrahlung and intra-nuclear interactions of forming hadrons. More data are required to gain a more complete understanding of these effects. Purpose: To test the theoretical models of parton transport and hadron formation, we compared their predictions for the nuclear and kinematic dependence of pion production in nuclei. Methods: We have measured charged-pion production in semi-inclusive DIS off D, C, Fe, and Pb using the CLAS detector and the CEBAF 5.014 GeV electron beam. We report results on the nuclear-to-deuterium multiplicity ratio for $\pi^{+}$ and $\pi^{-}$ as a function of energy transfer, four-momentum transfer, and pion energy fraction or transverse momentum - the first three-dimensional study of its kind. Results: The $\pi^{+}$ multiplicity ratio is found to depend strongly on the pion fractional energy $z$, and reaches minimum values of $0.67\pm0.03$, $0.43\pm0.02$, and $0.27\pm0.01$ for the C, Fe, and Pb targets, respectively. The $z$ dependences of the multiplicity ratios for $\pi^{+}$ and $\pi^{-}$ are equal within uncertainties for C and Fe targets but show differences at the level of 10$\%$ for the Pb-target data. The results are qualitatively described by the GiBUU transport model, as well as with a model based on hadron absorption, but are in tension with calculations based on nuclear fragmentation functions. Conclusions: These precise results will strongly constrain the kinematic and flavor dependence of nuclear effects in hadron production, probing an unexplored kinematic region. They will help to reveal how the nucleus reacts to a fast quark, thereby shedding light on its color structure, transport properties, and on the mechanisms of the hadronization process., Comment: 22 pages, 5 figures, 12 tables

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