Author: "Gaskell, D" / Topic: nuclear theory - Searchworks@Jio Institute Digital Library Search Results

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1. Pion electroproduction measurements in the nucleon resonance region

Author: Li, R., Sparveris, N., Atac, H., Jones, M. K., Paolone, M., Akbar, Z., Ali, M., Gayoso, C. Ayerbe, Berdnikov, V., Biswas, D., Boer, M., Camsonne, A., Chen, J. -P., Diefenthaler, M., Duran, B., Dutta, D., Gaskell, D., Hansen, O., Hauenstein, F., Heinrich, N., Henry, W., Horn, T., Huber, G. M., Jia, S., Joosten, S., Karki, A., Kay, S. J. D., Kumar, V., Li, X., Li, W. B., Liyanage, A. H., Mack, D., Malace, S., Markowitz, P., McCaughan, M., Meziani, Z. -E., Mkrtchyan, H., Morean, C., Muhoza, M., Narayan, A., Pasquini, B., Rehfuss, M., Sawatzky, B., Smith, G. R., Smith, A., Trotta, R., Yero, C., Zheng, X., and Zhou, J.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: We report new pion electroproduction measurements in the $\Delta(1232)$ resonance, utilizing the SHMS - HMS magnetic spectrometers of Hall C at Jefferson Lab. The data focus on a region that exhibits a strong and rapidly changing interplay of the mesonic cloud and quark-gluon dynamics in the nucleon. The results are in reasonable agreement with models that employ pion cloud effects and chiral effective field theory calculations, but at the same time they suggest that an improvement is required to the theoretical calculations and provide valuable input that will allow their refinements. The data illustrate the potential of the magnetic spectrometers setup in Hall C towards the study the $\Delta(1232)$ resonance. These first reported results will be followed by a series of measurements in Hall C, that will expand the studies of the $\Delta(1232)$ resonance offering a high precision insight within a wide kinematic range from low to high momentum transfers.
Published: 2024
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2. Flavor Dependence of Charged Pion Fragmentation Functions

Author: Bhatt, H., Bosted, P., Jia, S., Armstrong, W., Dutta, D., Ent, R., Gaskell, D., Kinney, E., Mkrtchyan, H., Ali, S., Ambrose, R., Androic, D., Gayoso, C. Ayerbe, Bandari, A., Berdnikov, V., Bhetuwal, D., Biswas, D., Boer, M., Brash, E., Camsonne, A., Chen, J. P., Chen, J., Chen, M., Christy, E. M., Covrig, S., Danagoulian, S., Diefenthaler, M., Duran, B., Elaasar, M., Elliot, C., Fenker, H., Fuchey, E., Hansen, J. O., Hauenstein, F., Horn, T., Huber, G. M., Jones, M. K., Kabir, M. L., Karki, A., Karki, B., Kay, S. J. D., Keppel, C., Kumar, V., Lashley-Colthirst, N., Li, W. B., Mack, D., Malace, S., Markowitz, P., McCaughan, M., McClellan, E., Meekins, D., Michaels, R., Mkrtchyan, A., Niculescu, G., Niculescu, I., Pandey, B., Park, S., Pooser, E., Rehfuss, M., Sawatzky, B., Smith, G. R., Szumila-Vance, H., Tadepalli, A. S., Tadevosyan, V., Trotta, R., Voskanyan, H., Wood, S. A., Ye, Z., Yero, C., and Zheng, X.
Subjects: Nuclear Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: We have measured the flavor dependence of multiplicities for pi^+ and pi^- production in semi-inclusive deep-inelastic scattering (SIDIS) on proton and deuteron targets to explore a possible charge symmetry violation in fragmentation functions. The experiment used an electron beam with energies of 10.2 and 10.6 GeV at Jefferson Lab and the Hall-C spectrometers. The electron kinematics spanned the range 0.3
Published: 2024

3. 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

4. The Present and Future of QCD

Author: Achenbach, P., Adhikari, D., Afanasev, A., Afzal, F., Aidala, C. A., Al-bataineh, A., Almaalol, D. K., Amaryan, M., Androić, D., Armstrong, W. R., Arratia, M., Arrington, J., Asaturyan, A., Aschenauer, E. C., Atac, H., Avakian, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Barish, K. N., Barnea, N., Basar, G., Battaglieri, M., Baty, A. A., Bautista, I., Bazilevsky, A., Beattie, C., Behera, S. C., Bellini, V., Bellwied, R., Benesch, J. F., Benmokhtar, F., Bernardes, C. A., Bernauer, J. C., Bhatt, H., Bhatta, S., Boer, M., Boettcher, T. J., Bogacz, S. A., Bossi, H. J., Brandenburg, J. D., Brash, E. J., Briceño, R. A., Briscoe, W. J., Brodsky, S. J., Brown, D. A., Burkert, V. D., Caines, H., Cali, I. A., Camsonne, A., Carman, D. S., Caylor, J., Cerci, S., Llatas, M. Chamizo, Chatterjee, S., Chen, J. P., Chen, Y., Chen, Y. -C., Chien, Y. -T., Chou, P. -C., Chu, X., Chudakov, E., Cline, E., Cloët, I. C., Cole, P. L., Connors, M. E., Constantinou, M., Cosyn, W., Dusa, S. Covrig, Cruz-Torres, R., D'Alesio, U., da Silva, C., Davoudi, Z., Dean, C. T., Dean, D. J., Demarteau, M., Deshpande, A., Detmold, W., Deur, A., Devkota, B. R., Dhital, S., Diefenthaler, M., Dobbs, S., Döring, M., Dong, X., Dotel, R., Dow, K. A., Downie, E. J., Drachenberg, J. L., Dumitru, A., Dunlop, J. C., Dupre, R., Durham, J. M., Dutta, D., Edwards, R. G., Ehlers, R. J., Fassi, L. El, Elaasar, M., Elouadrhiri, L., Engelhardt, M., Ent, R., Esumi, S., Evdokimov, O., Eyser, O., Fanelli, C., Fatemi, R., Fernando, I. P., Flor, F. A., Fomin, N., Frawley, A. D., Frederico, T., Fries, R. J., Gal, C., Gamage, B. R., Gamberg, L., Gao, H., Gaskell, D., Geurts, F., Ghandilyan, Y., Ghimire, N., Gilman, R., Gleason, C., Gnanvo, K., Gothe, R. W., Greene, S. V., Grießhammer, H. W., Grossberndt, S. K., Grube, B., Hackett, D. C., Hague, T. J., Hakobyan, H., Hansen, J. -O., Hatta, Y., Hattawy, M., Havener, L. B., Hen, O., Henry, W., Higinbotham, D. W., Hobbs, T. J., Hodges, A. M., Holmstrom, T., Hong, B., Horn, T., Howell, C. R., Huang, H. Z., Huang, M., Huang, S., Huber, G. M., Hyde, C. E., Isupov, E. L., Jacobs, P. M., Jalilian-Marian, J., Jentsch, A., Jheng, H., Ji, C. -R., Ji, X., Jia, J., Jones, D. C., Jones, M. K., Kalantarians, N., Kalicy, G., Kang, Z. B., Karthein, J. M., Keller, D., Keppel, C., Khachatryan, V., Kharzeev, D. E., Kim, H., Kim, M., Kim, Y., King, P. M., Kinney, E., Klein, S. R., Ko, H. S., Koch, V., Kohl, M., Kovchegov, Y. V., Krintiras, G. K., Kubarovsky, V., Kuhn, S. E., Kumar, K. S., Kutz, T., Lajoie, J. G., Lauret, J., Lavrukhin, I., Lawrence, D., Lee, J. H., Lee, K., Lee, S., Lee, Y. -J., Li, S., Li, W., Li, Xiaqing, Li, Xuan, Liao, J., Lin, H. -W., Lisa, M. A., Liu, K. -F., Liu, M. X., Liu, T., Liuti, S., Liyanage, N., Llope, W. J., Loizides, C., Longo, R., Lorenzon, W., Lunkenheimer, S., Luo, X., Ma, R., McKinnon, B., Meekins, D. G., Mehtar-Tani, Y., Melnitchouk, W., Metz, A., Meyer, C. A., Meziani, Z. -E., Michaels, R., Michel, J. K. L., Milner, R. G., Mkrtchyan, H., Mohanmurthy, P., Mohanty, B., Mokeev, V. I., Moon, D. H., Mooney, I. A., Morningstar, C., Morrison, D. P., Müller, B., Mukherjee, S., Mulligan, J., Camacho, C. Munoz, Quijada, J. A. Murillo, Murray, M. J., Nadeeshani, S. A., Nadel-Turonski, P., Nam, J. D., Nattrass, C. E., Nijs, G., Noronha, J., Noronha-Hostler, J., Novitzky, N., Nycz, M., Olness, F. I., Osborn, J. D., Pak, R., Pandey, B., Paolone, M., Papandreou, Z., Paquet, J. -F., Park, S., Paschke, K. D., Pasquini, B., Pasyuk, E., Patel, T., Patton, A., Paudel, C., Peng, C., Peng, J. C., Da Costa, H. Pereira, Perepelitsa, D. V., Peters, M. J., Petreczky, P., Pisarski, R. D., Pitonyak, D., Ploskon, M. A., Posik, M., Poudel, J., Pradhan, R., Prokudin, A., Pruneau, C. A., Puckett, A. J. R., Pujahari, P., Putschke, J., Pybus, J. R., Qiu, J. -W., Rajagopal, K., Ratti, C., Read, K. F., Reed, R., Richards, D. G., Riedl, C., Ringer, F., Rinn, T., West, J. Rittenhouse, Roche, J., Rodas, A., Roland, G., Romero-López, F., Rossi, P., Rostomyan, T., Ruan, L., Ruimi, O. M., Saha, N. R., Sahoo, N. R., Sakaguchi, T., Salazar, F., Salgado, C. W., Salmè, G., Salur, S., Santiesteban, S. N., Sargsian, M. M., Sarsour, M., Sato, N., Satogata, T., Sawada, S., Schäfer, T., Scheihing-Hitschfeld, B., Schenke, B., Schindler, S. T., Schmidt, A., Seidl, R., Shabestari, M. H., Shanahan, P. E., Shen, C., Sheng, T. -A., Shepherd, M. R., Sickles, A. M., Sievert, M. D., Smith, K. L., Song, Y., Sorensen, A., Souder, P. A., Sparveris, N., Srednyak, S., Leiton, A. G. Stahl, Stasto, A. M., Steinberg, P., Stepanyan, S., Stephanov, M., Stevens, J. R., Stewart, D. J., Stewart, I. W., Stojanovic, M., Strakovsky, I., Strauch, S., Strickland, M., Cerci, D. Sunar, Suresh, M., Surrow, B., Syritsyn, S., Szczepaniak, A. P., Tadepalli, A. S., Tang, A. H., Takaki, J. D. Tapia, Tarnowsky, T. J., Tawfik, A. N., Taylor, M. I., Tennant, C., Thiel, A., Thomas, D., Tian, Y., Timmins, A. R., Tribedy, P., Tu, Z., Tuo, S., Ullrich, T., Umaka, E., Upton, D. W., Vary, J. P., Velkovska, J., Venugopalan, R., Vijayakumar, A., Vitev, I., Vogelsang, W., Vogt, R., Vossen, A., Voutier, E., Vovchenko, V., Walker-Loud, A., Wang, F., Wang, J., Wang, X., Wang, X. -N., Weinstein, L. B., Wenaus, T. J., Weyhmiller, S., Wissink, S. W., Wojtsekhowski, B., Wong, C. P., Wood, M. H., Wunderlich, Y., Wyslouch, B., Xiao, B. W., Xie, W., Xiong, W., Xu, N., Xu, Q. H., Xu, Z., Yaari, D., Yao, X., Ye, Z., Ye, Z. H., Yero, C., Yuan, F., Zajc, W. A., Zhang, C., Zhang, J., Zhao, F., Zhao, Y., Zhao, Z. W., Zheng, X., Zhou, J., and Zurek, M.
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Experiment, Nuclear Experiment, Nuclear Theory
Abstract: This White Paper presents the community inputs and scientific conclusions from the Hot and Cold QCD Town Meeting that took place September 23-25, 2022 at MIT, as part of the Nuclear Science Advisory Committee (NSAC) 2023 Long Range Planning process. A total of 424 physicists registered for the meeting. The meeting highlighted progress in Quantum Chromodynamics (QCD) nuclear physics since the 2015 LRP (LRP15) and identified key questions and plausible paths to obtaining answers to those questions, defining priorities for our research over the coming decade. In defining the priority of outstanding physics opportunities for the future, both prospects for the short (~ 5 years) and longer term (5-10 years and beyond) are identified together with the facilities, personnel and other resources needed to maximize the discovery potential and maintain United States leadership in QCD physics worldwide. This White Paper is organized as follows: In the Executive Summary, we detail the Recommendations and Initiatives that were presented and discussed at the Town Meeting, and their supporting rationales. Section 2 highlights major progress and accomplishments of the past seven years. It is followed, in Section 3, by an overview of the physics opportunities for the immediate future, and in relation with the next QCD frontier: the EIC. Section 4 provides an overview of the physics motivations and goals associated with the EIC. Section 5 is devoted to the workforce development and support of diversity, equity and inclusion. This is followed by a dedicated section on computing in Section 6. Section 7 describes the national need for nuclear data science and the relevance to QCD research., Comment: QCD Town Meeting White Paper, as submitted to 2023 NSAC LRP committee on Feb. 28, 2023
Published: 2023
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5. Measured proton electromagnetic structure deviates from theoretical predictions

Author: Li, R., Sparveris, N., Atac, H., Jones, M. K., Paolone, M., Akbar, Z., Gayoso, C. Ayerbe, Berdnikov, V., Biswas, D., Boer, M., Camsonne, A., Chen, J. -P., Diefenthaler, M., Duran, B., Dutta, D., Gaskell, D., Hansen, O., Hauenstein, F., Heinrich, N., Henry, W., Horn, T., Huber, G. M., Jia, S., Joosten, S., Karki, A., Kay, S. J. D., Kumar, V., Li, X., Li, W. B., Liyanage, A. H., Malace, S., Markowitz, P., McCaughan, M., Meziani, Z. -E., Mkrtchyan, H., Morean, C., Muhoza, M., Narayan, A., Pasquini, B., Rehfuss, M., Sawatzky, B., Smith, G. R., Smith, A., Trotta, R., Yero, C., Zheng, X., and Zhou, J.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state.A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.
Published: 2022
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6. Precision Determination of the Neutral Weak Form Factor of $^{48}$Ca

Author: Adhikari, D., Albataineh, H., Androic, D., Aniol, K. A., Armstrong, D. S., Averett, T., Gayoso, C. Ayerbe, Barcus, S. K., Bellini, V., Beminiwattha, R. S., Benesch, J. F., Bhatt, H., Pathak, D. Bhatta, Bhetuwal, D., Blaikie, B., Boyd, J., Campagna, Q., Camsonne, A., Cates, G. D., Chen, Y., Clarke, C., Cornejo, J. C., Dusa, S. Covrig, Dalton, M. M., Datta, P., Deshpande, A., Dutta, D., Feldman, C., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Gericke, M., Ghosh, C., Halilovic, I., Hansen, J. -O., Hassan, O., Hauenstein, F., Henry, W., Horowitz, C. J., Jantzi, C., Jian, S., Johnston, S., Jones, D. C., Kakkar, S., Katugampola, S., Keppel, C., King, P. M., King, D. E., Kumar, K. S., Kutz, T., Lashley-Colthirst, N., Leverick, G., Liu, H., Liyanage, N., Mammei, J., Mammei, R., McCaughan, 23 M., McNulty, D., Meekins, D., Metts, C., Michaels, R., Mihovilovic, M., Mondal, M. M., Napolitano, J., Narayan, A., Nikolaev, D., Owen, V., Palatchi, C., Pan, J., Pandey, B., Park, S., Paschke, K. D., Petrusky, M., Pitt, M. L., Premathilake, S., Quinn, B., Radloff, R., Rahman, S., Rashad, M. N. H., Rathnayake, A., Reed, B. T., Reimer, P. E., Richards, R., Riordan, S., Roblin, Y. R., Seeds, S., Shahinyan, A., Souder, P., Thiel, M., Tian, Y., Urciuoli, G. M., Wertz, E. W., Wojtsekhowski, B., Yale, B., Ye, T., Yoon, A., Xiong, W., Zec, A., Zhang, W., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: We report a precise measurement of the parity-violating asymmetry $A_{\rm PV}$ in the elastic scattering of longitudinally polarized electrons from $^{48}{\rm Ca}$. We measure $A_{\rm PV} =2668\pm 106\ {\rm (stat)}\pm 40\ {\rm (syst)}$ parts per billion, leading to an extraction of the neutral weak form factor $F_{\rm W} (q=0.8733$ fm$^{-1}) = 0.1304 \pm 0.0052 \ {\rm (stat)}\pm 0.0020\ {\rm (syst)}$ and the charge minus the weak form factor $F_{\rm ch} - F_{\rm W} = 0.0277\pm 0.0055$. The resulting neutron skin thickness $R_n-R_p=0.121 \pm 0.026\ {\rm (exp)} \pm 0.024\ {\rm (model)}$~fm is relatively thin yet consistent with many model calculations. The combined CREX and PREX results will have implications for future energy density functional calculations and on the density dependence of the symmetry energy of nuclear matter., Comment: 8 pages, 5 figures Replace 6-16-22: included ancillary files, corrected errors in references, author affiliations. Small text changes for clarity
Published: 2022
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7. Measurement of the EMC effect in light and heavy nuclei

Author: Arrington, J., Bane, J., Daniel, A., Fomin, N., Gaskell, D., Seely, J., Asaturyan, R., Benmokhtar, F., Boeglin, W., Bosted, P., Bukhari, M. H. S., Christy, M. E., Connell, S., Dalton, M. M., Day, D., Dunne, J., Dutta, D., Fassi, L. El, Ent, R., Fenker, H., Gao, H., Holt, R. J., Horn, T., Hungerford, E., Jones, M. K., Jourdan, J., Kalantarians, N., Keppel, C. E., Kiselev, D., Lung, A. F., Malace, S., Meekins, D. G., Mertens, T., Mkrtchyan, H., Niculescu, G., Niculescu, I., Potterveld, D. H., Perdrisat, C., Punjabi, V., Qian, X., Reimer, P. E., Roche, J., Rodriguez, V. M., Rondon, O., Schulte, E., Slifer, K., Smith, G. R., Solvignon, P., Tadevosyan, V., Tang, L., Testa, G., Trojer, R., Tvaskis, V., Wesselmann, F. R., Wood, S. A., Yuan, L., and Zheng, X.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: Inclusive electron scattering from nuclear targets has been measured to extract the nuclear dependence of the inelastic cross section in Hall C at the Thomas Jefferson National Accelerator facility. Results are presented for 2H, 3He, 4He, 9B, 12C, 63Cu and 197Au at an incident electron beam energy of 5.77 GeV for a range of momentum transfer from Q^2 = 2 to 7 (GeV/c)^2. These data improve the precision of the existing measurements of the EMC effect in the nuclear targets at large x, and allow for more detailed examinations of the A dependence of the EMC effect., Comment: 28 pages, 23 figures, archival paper for Jefferson Lab experiment E03-103
Published: 2021
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8. Science Requirements and Detector Concepts for the Electron-Ion Collider: EIC Yellow Report

Author: Khalek, R. Abdul, Accardi, A., Adam, J., Adamiak, D., Akers, W., Albaladejo, M., Al-bataineh, A., Alexeev, M. G., Ameli, F., Antonioli, P., Armesto, N., Armstrong, W. R., Arratia, M., Arrington, J., Asaturyan, A., Asai, M., Aschenauer, E. C., Aune, S., Avagyan, H., Gayoso, C. Ayerbe, Azmoun, B., Bacchetta, A., Baker, M. D., Barbosa, F., Barion, L., Barish, K. N., Barry, P. C., Battaglieri, M., Bazilevsky, A., Behera, N. K., Benmokhtar, F., Berdnikov, V. V., Bernauer, J. C., Bertone, V., Bhattacharya, S., Bissolotti, C., Boer, D., Boglione, M., Bondì, M., Boora, P., Borsa, I., Bossù, F., Bozzi, G., Brandenburg, J. D., Brei, N., Bressan, A., Brooks, W. K., Bufalino, S., Bukhari, M. H. S., Burkert, V., Buttimore, N. H., Camsonne, A., Celentano, A., Celiberto, F. G., Chang, W., Chatterjee, C., Chen, K., Chetry, T., Chiarusi, T., Chien, Y. -T., Chiosso, M., Chu, X., Chudakov, E., Cicala, G., Cisbani, E., Cloet, I. C., Cocuzza, C., Cole, P. L., Colella, D., Collins II, J. L., Constantinou, M., Contalbrigo, M., Contin, G., Corliss, R., Cosyn, W., Courtoy, A., Crafts, J., Cruz-Torres, R., Cuevas, R. C., D'Alesio, U., Torre, S. Dalla, Das, D., Dasgupta, S. S., Da Silva, C., Deconinck, W., Defurne, M., DeGraw, W., Dehmelt, K., Del Dotto, A., Delcarro, F., Deshpande, A., Detmold, W., De Vita, R., Diefenthaler, M., Dilks, C., Dixit, D. U., Dulat, S., Dumitru, A., Dupré, R., Durham, J. M., Echevarria, M. G., Fassi, L. El, Elia, D., Ent, R., Esha, R., Ethier, J. J., Evdokimov, O., Eyser, K. O., Fanelli, C., Fatemi, R., Fazio, S., Fernandez-Ramirez, C., Finger, M., Finger Jr., M., Fitzgerald, D., Flore, C., Frederico, T., Friščić, I., Fucini, S., Furletov, S., Furletova, Y., Gal, C., Gamberg, L., Gao, H., Garg, P., Gaskell, D., Gates, K., Ducati, M. B. Gay, Gericke, M., da Silveira, G. Gil, Girod, F. -X., Glazier, D. I., Gnanvo, K., Goncalves, V. P., Gonella, L., Hernandez, J. O. Gonzalez, Goto, Y., Grancagnolo, F., Greiner, L. C., Guryn, W., Guzey, V., Hatta, Y., Hattawy, M., Hauenstein, F., He, X., Hemmick, T. K., Hen, O., Heyes, G., Higinbotham, D. W., Blin, A. N. Hiller, Hobbs, T. J., Hohlmann, M., Horn, T., Hou, T. -J., Huang, J., Huang, Q., Huber, G. M., Hyde, C. E., Iakovidis, G., Ilieva, Y., Jacak, B. V., Jacobs, P. M., Jadhav, M., Janoska, Z., Jentsch, A., Jezo, T., Jing, X., Jones, P. G., Joo, K., Joosten, S., Kafka, V., Kalantarians, N., Kalicy, G., Kang, D., Kang, Z. B., Kauder, K., Kay, S. J. D., Keppel, C. E., Kim, J., Kiselev, A., Klasen, M., Klein, S., Klest, H. T., Korchak, O., Kostina, A., Kotko, P., Kovchegov, Y. V., Krelina, M., Kuleshov, S., Kumano, S., Kumar, K. S., Kumar, R., Kumar, L., Kumerički, K., Kusina, A., Kutak, K., Lai, Y. S., Lalwani, K., Lappi, T., Lauret, J., Lavinsky, M., Lawrence, D., Lednicky, D., Lee, C., Lee, K., Lee, S. H., Levorato, S., Li, H., Li, S., Li, W., Li, X., Li, W. B., Ligonzo, T., Liu, H., Liu, M. X., Liu, X., Liuti, S., Liyanage, N., Lorcé, C., Lu, Z., Lucero, G., Lukow, N. S., Lunghi, E., Majka, R., Makris, Y., Mandjavidze, I., Mantry, S., Mäntysaari, H., Marhauser, F., Markowitz, P., Marsicano, L., Mastroserio, A., Mathieu, V., Mehtar-Tani, Y., Melnitchouk, W., Mendez, L., Metz, A., Meziani, Z. -E., Mezrag, C., Mihovilovič, M., Milner, R., Mirazita, M., Mkrtchyan, H., Mkrtchyan, A., Mochalov, V., Moiseev, V., Mondal, M. M., Morreale, A., Morrison, D., Motyka, L., Moutarde, H., Camacho, C. Muñoz, Murgia, F., Murray, M. J., Musico, P., Nadel-Turonski, P., Nadolsky, P. M., Nam, J., Newman, P. R., Neyret, D., Nguyen, D., Nocera, E. R., Noferini, F., Noto, F., Nunes, A. S., Okorokov, V. A., Olness, F., Osborn, J. D., Page, B. S., Park, S., Parker, A., Paschke, K., Pasquini, B., Paukkunen, H., Paul, S., Pecar, C., Pegg, I. L., Pellegrino, C., Peng, C., Pentchev, L., Perrino, R., Petriello, F., Petti, R., Pilloni, A., Pinkenburg, C., Pire, B., Pisano, C., Pitonyak, D., Poblaguev, A. A., Polakovic, T., Posik, M., Potekhin, M., Preghenella, R., Preins, S., Prokudin, A., Pujahari, P., Purschke, M. L., Pybus, J. R., Radici, M., Rajput-Ghoshal, R., Reimer, P. E., Rinaldi, M., Ringer, F., Roberts, C. D., Rodini, S., Rojo, J., Romanov, D., Rossi, P., Santopinto, E., Sarsour, M., Sassot, R., Sato, N., Schenke, B., Schmidke, W. B., Schmidt, I., Schmidt, A., Schmookler, B., Schnell, G., Schweitzer, P., Schwiening, J., Scimemi, I., Scopetta, S., Segovia, J., Seidl, R., Sekula, S., Semenov-Tian-Shanskiy, K., Shao, D. Y., Sherrill, N., Sichtermann, E., Siddikov, M., Signori, A., Singh, B. K., Širca, S., Slifer, K., Slominski, W., Sokhan, D., Sondheim, W. E., Song, Y., Soto, O., Spiesberger, H., Stasto, A. M., Stepanov, P., Sterman, G., Stevens, J. R., Stewart, I. W., Strakovsky, I., Strikman, M., Sturm, M., Stutzman, M. L., Sullivan, M., Surrow, B., Svihra, P., Syritsyn, S., Szczepaniak, A., Sznajder, P., Szumila-Vance, H., Szymanowski, L., Tadepalli, A. S., Takaki, J. D. Tapia, Tassielli, G. F., Terry, J., Tessarotto, F., Tezgin, K., Tomasek, L., Acosta, F. Torales, Tribedy, P., Tricoli, A., Triloki, Tripathi, S., Trotta, R. L., Tsai, O. D., Tu, Z., Tuvè, C., Ullrich, T., Ungaro, M., Urciuoli, G. M., Valentini, A., Vancura, P., Vandenbroucke, M., Van Hulse, C., Varner, G., Venugopalan, R., Vitev, I., Vladimirov, A., Volpe, G., Vossen, A., Voutier, E., Wagner, J., Wallon, S., Wang, H., Wang, Q., Wang, X., Wei, S. Y., Weiss, C., Wenaus, T., Wennlöf, H., Wickramaarachchi, N., Wikramanayake, A., Winney, D., Wong, C. P., Woody, C., Xia, L., Xiao, B. W., Xie, J., Xing, H., Xu, Q. H., Zhang, J., Zhang, S., Zhang, Z., Zhao, Z. W., Zhao, Y. X., Zheng, L., Zhou, Y., and Zurita, P.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Experiment, Nuclear Theory
Abstract: This report describes the physics case, the resulting detector requirements, and the evolving detector concepts for the experimental program at the Electron-Ion Collider (EIC). The EIC will be a powerful new high-luminosity facility in the United States with the capability to collide high-energy electron beams with high-energy proton and ion beams, providing access to those regions in the nucleon and nuclei where their structure is dominated by gluons. Moreover, polarized beams in the EIC will give unprecedented access to the spatial and spin structure of the proton, neutron, and light ions. The studies leading to this document were commissioned and organized by the EIC User Group with the objective of advancing the state and detail of the physics program and developing detector concepts that meet the emerging requirements in preparation for the realization of the EIC. The effort aims to provide the basis for further development of concepts for experimental equipment best suited for the science needs, including the importance of two complementary detectors and interaction regions. This report consists of three volumes. Volume I is an executive summary of our findings and developed concepts. In Volume II we describe studies of a wide range of physics measurements and the emerging requirements on detector acceptance and performance. Volume III discusses general-purpose detector concepts and the underlying technologies to meet the physics requirements. These considerations will form the basis for a world-class experimental program that aims to increase our understanding of the fundamental structure of all visible matter, Comment: 902 pages, 415 authors, 151 institutions
Published: 2021
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9. Ruling out color transparency in quasi-elastic $^{12}$C(e,e'p) up to $Q^2$ of 14.2 (GeV/c)$^2$

Author: Bhetuwal, D., Matter, J., Szumila-Vance, H., Kabir, M. L., Dutta, D., Ent, R., Abrams, D., Ahmed, Z., Aljawrneh, B., Alsalmi, S., Ambrose, R., Androic, D., Armstrong, W., Asaturyan, A., Assumin-Gyimah, K., Gayoso, C. Ayerbe, Bandari, A., Basnet, S., Berdnikov, V., Bhatt, H., Biswas, D., Boeglin, W. U., Bosted, P., Brash, E., Bukhari, M. H. S., Chen, H., Chen, J. P., Chen, M., Christy, E. M., Covrig, S., Craycraft, K., Danagoulian, S., Day, D., Diefenthaler, M., Dlamini, M., Dunne, J., Duran, B., Evans, R., Fenker, H., Fomin, N., Fuchey, E., Gaskell, D., Gautam, T. N., Gonzalez, F. A., Hansen, J. O., Hauenstein, F., Hernandez, A. V., Horn, T., Huber, G. M., Jones, M. K., Joosten, S., Karki, A., Keppel, C., Khanal, A., King, P. M., Kinney, E., Ko, H. S., Kohl, M., Lashley-Colthirst, N., Li, S., Li, W. B., Liyanage, A. H., Mack, D., Malace, S., Markowitz, P., Meekins, D., Michaels, R., Mkrtchyan, A., Mkrtchyan, H., Nazeer, S. J., Nanda, S., Niculescu, G., Niculescu, I., Nguyen, D., Nuruzzaman, Pandey, B., Park, S., Pooser, E., Puckett, A., Rehfuss, M., Reinhold, J., Santiesteban, N., Sawatzky, B., Smith, G. R., Sun, A., Tadevosyan, V., Trotta, R., Wood, S. A., Yero, C., and Zhang, J.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: Quasielastic $^{12}$C$(e,e'p)$ scattering was measured at space-like 4-momentum transfer squared $Q^2$~=~8, 9.4, 11.4, and 14.2 (GeV/c)$^2$, the highest ever achieved to date. Nuclear transparency for this reaction was extracted by comparing the measured yield to that expected from a plane-wave impulse approximation calculation without any final state interactions. The measured transparency was consistent with no $Q^2$ dependence, up to proton momenta of 8.5~GeV/c, ruling out the quantum chromodynamics effect of color transparency at the measured $Q^2$ scales in exclusive $(e,e'p)$ reactions. These results impose strict constraints on models of color transparency for protons., Comment: 5 pages, 2 figures
Published: 2020
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10. Unique Access to u-Channel Physics: Exclusive Backward-Angle Omega Meson Electroproduction

Author: Li, W. B., Huber, G. M., Blok, H. P., Gaskell, D., Horn, T., Semenov-Tian-Shansky, K., Pire, B., Szymanowski, L., Laget, J. -M., Aniol, K., Arrington, J., Beise, E. J., Boeglin, W., Brash, E. J., Breuer, H., Chang, C. C., Christy, M. E., Ent, R., Gibson, E. F., Holt, R. J., Jin, S., Jones, M. K., Keppel, C. E., Kim, W., King, P. M., Kovaltchouk, V., Liu, J., Lolos, G. J., Mack, D. J., Margaziotis, D. J., Markowitz, P., Matsumura, A., Meekins, D., Miyoshi, T., Mkrtchyan, H., Niculescu, I., Okayasu, Y., Pentchev, L., Perdrisat, C., Potterveld, D., Punjabi, V., Reimer, P. E., Reinhold, J., Roche, J., Roos, P. G., Sarty, A., Smith, Tadevosyan, V., Tang, L. G., Tvaskis, V., Volmer, J., Vulcan, W., Warren, G., Wood, S. A., Xu, C., and Zheng, X.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: Backward-angle meson electroproduction above the resonance region, which was previously ignored, is anticipated to offer unique access to the three quark plus sea component of the nucleon wave function. In this letter, we present the first complete separation of the four electromagnetic structure functions above the resonance region in exclusive omega electroproduction off the proton, e + p -> e' + p + omega, at central Q^2 values of 1.60, 2.45 GeV^2 , at W = 2.21 GeV. The results of our pioneering -u ~ -u min study demonstrate the existence of a unanticipated backward-angle cross section peak and the feasibility of full L/T/LT/TT separations in this never explored kinematic territory. At Q^2 =2.45 GeV^2 , the observed dominance of sigma_T over sigma_L, is qualitatively consistent with the collinear QCD description in the near-backward regime, in which the scattering amplitude factorizes into a hard subprocess amplitude and baryon to meson transition distribution amplitudes (TDAs): universal non-perturbative objects only accessible through backward angle kinematics.
Published: 2019

11. Exposing Novel Quark and Gluon Effects in Nuclei

Author: Cloët, I. C., Dupré, R., Riordan, S., Armstrong, W., Arrington, J., Cosyn, W., Fomin, N., Freese, A., Fucini, S., Gaskell, D., Keppel, C. E., Miller, G. A., Pace, E., Platchkov, S., Reimer, P. E., Scopetta, S., Thomas, A. W., and Zurita, P.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: The fundamental theory of the strong interaction -- quantum chromodynamics (QCD) -- provides the foundational framework with which to describe and understand the key properties of atomic nuclei. A deep understanding of the explicit role of quarks and gluons in nuclei remains elusive however, as these effects have thus far been well-disguised by confinement effects in QCD which are encapsulated by a successful description in terms of effective hadronic degrees of freedom. The observation of the EMC effect has provided an enduring indication for explicit QCD effects in nuclei, and points to the medium modification of the bound protons and neutrons in the nuclear medium. Understanding the EMC effect is a major challenge for modern nuclear physics, and several key questions remain, such as understanding its flavor, spin, and momentum dependence. This manuscript provides a contemporary snapshot of our understanding of the role of QCD in nuclei and outlines possible pathways in experiment and theory that will help deepen our understanding of nuclei in the context of QCD.
Published: 2019
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12. Spectroscopy of the neutron-rich hypernucleus $^{7}_{\Lambda}$He from electron scattering

Author: Gogami, T., Chen, C., Kawama, D., Achenbach, P., Ahmidouch, A., Albayrak, I., Androic, D., Asaturyan, A., Asaturyan, R., Ates, O., Baturin, P., Badui, R., Boeglin, W., Bono, J., Brash, E., Carter, P., Chiba, A., Christy, E., Danagoulian, S., De Leo, R., Doi, D., Elaasar, M., Ent, R., Fujii, Y., Fujita, M., Furic, M., Gabrielyan, M., Gan, L., Garibaldi, F., Gaskell, D., Gasparian, A., Han, Y., Hashimoto, O., Horn, T., Hu, B., Hungerford, Ed. V., Jones, M., Kanda, H., Kaneta, M., Kato, S., Kawai, M., Khanal, H., Kohl, M., Liyanage, A., Luo, W., Maeda, K., Margaryan, A., Markowitz, P., Maruta, T., Matsumura, A., Maxwell, V., Mkrtchyan, A., Mkrtchyan, H., Nagao, S., Nakamura, S. N., Narayan, A., Neville, C., Niculescu, G., Niculescu, M. I., Nunez, A., Nuruzzaman, Okayasu, Y., Petkovic, T., Pochodzalla, J., Qiu, X., Reinhold, J., Rodriguez, V. M., Samanta, C., Sawatzky, B., Seva, T., Shichijo, A., Tadevosyan, V., Tang, L., Taniya, N., Tsukada, K., Veilleux, M., Vulcan, W., Wesselmann, F. R., Wood, S. A., Yamamoto, T., Ya, L., Ye, Z., Yokota, K., Yuan, L., Zhamkochyan, S., and Zhu, L.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: The missing mass spectroscopy of the $^{7}_{\Lambda}$He hypernucleus was performed, using the $^{7}$Li$(e,e^{\prime}K^{+})^{7}_{\Lambda}$He reaction at the Thomas Jefferson National Accelerator Facility Hall C. The $\Lambda$ binding energy of the ground state (1/2$^{+}$) was determined with a smaller error than that of the previous measurement, being $B_{\Lambda}$ = 5.55 $\pm$ 0.10(stat.) $\pm$ 0.11(sys.) MeV. The experiment also provided new insight into charge symmetry breaking in p-shell hypernuclear systems. Finally, a peak at $B_{\Lambda}$ = 3.65 $\pm$ 0.20(stat.) $\pm$ 0.11(sys.) MeV was observed and assigned as a mixture of 3/2$^{+}$ and 5/2$^{+}$ states, confirming the "gluelike" behavior of $\Lambda$, which makes an unstable state in $^{6}$He stable against neutron emission., Comment: 6 pages, 4 figures
Published: 2016
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13. Precision Electron-Beam Polarimetry using Compton Scattering at 1 GeV

Author: Narayan, A., Jones, D., Cornejo, J. C., Dalton, M. M., Deconinck, W., Dutta, D., Gaskell, D., Martin, J. W., Paschke, K. D., Tvaskis, V., Asaturyan, A., Benesch, J., Cates, G., Cavness, B. S., Dillon-Townes, L. A., Hays, G., Ihloff, E., Jones, R., Kowalski, S., Kurchaninov, L., Lee, L., McCreary, A., McDonald, M., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Nelyubin, V., Page, S., Ramsay, W. D., Solvignon, P., Storey, D., Tobias, A., Urban, E., Vidal, C., Wang, P., and Zhamkotchyan, S.
Subjects: Nuclear Experiment, High Energy Physics - Phenomenology, Nuclear Theory, Physics - Accelerator Physics, Physics - Instrumentation and Detectors
Abstract: We report on the highest precision yet achieved in the measurement of the polarization of a low energy, $\mathcal{O}$(1 GeV), electron beam, accomplished using a new polarimeter based on electron-photon scattering, in Hall~C at Jefferson Lab. A number of technical innovations were necessary, including a novel method for precise control of the laser polarization in a cavity and a novel diamond micro-strip detector which was able to capture most of the spectrum of scattered electrons. The data analysis technique exploited track finding, the high granularity of the detector and its large acceptance. The polarization of the $180~\mu$A, $1.16$~GeV electron beam was measured with a statistical precision of $<$~1\% per hour and a systematic uncertainty of 0.59\%. This exceeds the level of precision required by the \qweak experiment, a measurement of the vector weak charge of the proton. Proposed future low-energy experiments require polarization uncertainty $<$~0.4\%, and this result represents an important demonstration of that possibility. This measurement is also the first use of diamond detectors for particle tracking in an experiment., Comment: 9 pages, 7 figures, published in PRX
Published: 2015
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14. Measurement of the Spectral Function of $^{40}$Ar through the $(e,e^\prime p)$ reaction

Author: Ankowski, A., Beminiwattha, R., Benhar, O., Crabb, D. G., Day, D. B., Garibaldi, F., Garvey, G., Gaskell, D., Giusti, C., Hansen, O., Higinbotham, D. W., Holmes, R., Jen, C. M., Jiang, X., Keller, D., Keppel, C. E., Lindgren, R., Link, J. M., Liyanage, N., Mariani, C., Meucci, A., Mills, G. B., Myers, L., Pitt, M. L., Rondon, O. A., Sakuda, M., Sawatzky, B., Souder, P. A., Urciuoli, G. M., Wood, S., and Zhang, J.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: The interpretation of the signals detected by high precision experiments aimed at measuring neutrino oscillations requires an accurate description of the neutrino-nucleus cross sections. One of the key element of the analysis is the treatment of nuclear effects, which is one of the main sources of systematics for accelerator based experiments such as the Long Baseline Neutrino Experiment (LBNE). A considerable effort is currently being made to develop theoretical models capable of providing a fully quantitative description of the neutrino-nucleus cross sections in the kinematical regime relevant to LBNE. The approach based on nuclear many-body theory and the spectral function formalism has proved very successful in explaining the available electron scattering data in a variety of kinematical conditions. The first step towards its application to the analysis of neutrino data is the derivation of the spectral functions of nuclei employed in neutrino detectors, in particular argon. We propose a measurement of the coincidence $(e,e^\prime p)$ cross section on argon. This data will provide the experimental input indispensable to construct the argon spectral function, thus paving the way for a reliable estimate of the neutrino cross sections. In addition, the analysis of the $(e,e^\prime p)$ data will help a number of theoretical developments, like the description of final-state interactions needed to isolate the initial-state contributions to the observed single-particle peaks, that is also needed for the interpretation of the signal detected in neutrino experiments., Comment: 28 pages, 4 figures, Proposal PR12-14-012 submitted to the JLAB PAC 42, July 2014
Published: 2014

15. Impact of nuclear dependence of R=\sigma_L/\sigma_T on antishadowing in nuclear structure functions

Author: Guzey, V., Zhu, L., Keppel, C., Christy, M. Eric, Gaskell, D., Solvignon, P., and Accardi, A.
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Experiment, Nuclear Experiment, Nuclear Theory
Abstract: We study the impact of the nuclear dependence of R=\sigma_L/\sigma_T on the extraction of the F_2^A/F_2^D and F_1^A/F_1^D structure function ratios from the data on the \sigma^A/\sigma^D cross section ratios. Guided by indications of the nuclear dependence of R from the world data, we examine selected sets of EMC, BCDMS, NMC and SLAC data and find that F_1^A/F_1^D < \sigma^A/\sigma^D \leq F_2^A/F_2^D. In particular, we observe that the nuclear enhancement (antishadowing) for F_1^A/F_1^D in the interval 0.1 < x < 0.3 becomes significantly reduced or even disappears, which indicates that antishadowing is dominated by the longitudinal structure function F_L. We also argue that precise measurements of nuclear modifications of R and F_L^A have the potential to constrain the poorly known gluon distribution in nuclei over a wide range of x., Comment: 9 pages, 8 figures, 1 table
Published: 2012
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16. Single Spin Asymmetries in Charged Pion Production from Semi-Inclusive Deep Inelastic Scattering on a Transversely Polarized $^3$He Target

Author: Qian, X., Allada, K., Dutta, C., Huang, J., Katich, J., Wang, Y., Zhang, Y., Aniol, K., Annand, J. R. M., Averett, T., Benmokhtar, F., Bertozzi, W., Bradshaw, P. C., Bosted, P., Camsonne, A., Canan, M., Cates, G. D., Chen, C., Chen, J. -P., Chen, W., Chirapatpimol, K., Chudakov, E., Cisbani, E., Cornejo, J. C., Cusanno, F., Dalton, M. M., Deconinck, W., de Jager, C. W., De Leo, R., Deng, X., Deur, A., Ding, H., Dolph, P. A. M., Dutta, D., Fassi, L. El, Frullani, S., Gao, H., Garibaldi, F., Gaskell, D., Gilad, S., Gilman, R., Glamazdin, O., Golge, S., Guo, L., Hamilton, D., Hansen, O., Higinbotham, D. W., Holmstrom, T., Huang, M., Ibrahim, H. F., Iodice, M., Jiang, X., Jin, G., Jones, M. K., Kelleher, A., Kim, W., Kolarkar, A., Korsch, W., LeRose, J. J., Li, X., Li, Y., Lindgren, R., Liyanage, N., Long, E., Lu, H. -J., Margaziotis, D. J., Markowitz, P., Marrone, S., McNulty, D., Meziani, Z. -E., Michaels, R., Moffit, B., Camacho, C. Munoz, Nanda, S., Narayan, A., Nelyubin, V., Norum, B., Oh, Y., Osipenko, M., Parno, D., Peng, J. C., Phillips, S. K., Posik, M., Puckett, A. J. R., Qiang, Y., Rakhman, A., Ransome, R. D., Riordan, S., Saha, A., Sawatzky, B., Schulte, E., Shahinyan, A., Shabestari, M. H., Širca, S., Stepanyan, S., Subedi, R., Sulkosky, V., Tang, L. -G., Tobias, A., Urciuoli, G. M., Vilardi, I., Wang, K., Wojtsekhowski, B., Yan, X., Yao, H., Ye, Y., Ye, Z., Yuan, L., Zhan, X., Zhang, Y. -W., Zhao, B., Zheng, X., Zhu, L., Zhu, X., and Zong, X.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: We report the first measurement of target single spin asymmetries in the semi-inclusive $^3{He}(e,e'\pi^\pm)X$ reaction on a transversely polarized target. The experiment, conducted at Jefferson Lab using a 5.9 GeV electron beam, covers a range of 0.14 $< x <$ 0.34 with 1.3 $
Published: 2011
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17. Transverse Beam Spin Asymmetries at Backward Angles in Elastic Electron-Proton and Quasi-elastic Electron-Deuteron Scattering

Author: The G0 Collaboration, Androić, D., Armstrong, D. S., Arvieux, J., Bailey, S. L., Beck, D. H., Beise, E. J., Benesch, J., Benmokhtar, F., Bimbot, L., Birchall, J., Bosted, P., Breuer, H., Capuano, C. L., Chao, Y. -C., Coppens, A., Davis, C. A., Ellis, C., Flores, G., Franklin, G., Furget, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guillard, G., Hansknecht, J., Horn, T., Jones, M. K., King, P. M., Korsch, W., Kox, S., Lee, L., Liu, J., Lung, A., Mammei, J., Martin, J. W., McKeown, R. D., Micherdzinska, A., Mihovilovic, M., Mkrtchyan, H., Muether, M., Page, S. A., Papavassiliou, V., Pate, S. F., Phillips, 10 S. K., Pillot, P., Pitt, M. L., Poelker, M., Quinn, B., Ramsay, W. D., Real, J. -S., Roche, J., Roos, P., Schaub, J., Seva, T., Simicevic, N., Smith, G. R., Spayde, D. T., Stutzman, M., Suleiman, R., Tadevosyan, V., van Oers, W. T. H., Versteegen, M., Voutier, E., Vulcan, W., Wells, S. P., Williamson, S. E., Wood, S. A., Pasquini, B., and Vanderhaeghen, M.
Subjects: Nuclear Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: We have measured the beam-normal single-spin asymmetries in elastic scattering of transversely polarized electrons from the proton, and performed the first measurement in quasi-elastic scattering on the deuteron, at backward angles (lab scattering angle of 108 degrees) for Q2 = 0.22 GeV^2/c^2 and 0.63 GeV^2/c^2 at beam energies of 362 MeV and 687 MeV, respectively. The asymmetry arises due to the imaginary part of the interference of the two-photon exchange amplitude with that of single photon exchange. Results for the proton are consistent with a model calculation which includes inelastic intermediate hadronic (piN) states. An estimate of the beam-normal single-spin asymmetry for the scattering from the neutron is made using a quasi-static deuterium approximation, and is also in agreement with theory.
Published: 2011
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18. Measurements of the EMC effect in few-body nuclei at large x

Author: Daniel, A., Arrington, J., and Gaskell, D.
Subjects: Nuclear Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: Recent data on the EMC effect from Jefferson Lab experiment E03103 suggest that the nuclear dependence of the high x quark distribution may depend on the local nuclear environment, rather than being a purely bulk effect. We briefly discuss the analysis and results of the E03103 experiment focusing on the light nuclei and high x region. In addition, we also discuss a future experiment at the upgraded 12 GeV Jefferson Lab facility which will further investigate the role of the local nuclear environment and the influence of detailed nuclear structure on the modification of quark distributions., Comment: 9 pages, 6 figures; based on talk given by A. Daniel at 3rd International Workshop on Nucleon Structure at Large Bjorken x, Jefferson Lab, October 13-15, 2010
Published: 2011
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19. Search for effects beyond the Born approximation in polarization transfer observables in $\vec{e}p$ elastic scattering

Author: Meziane, M., Brash, E. J., Gilman, R., Jones, M. K., Luo, W., Pentchev, L., Perdrisat, C. F., Puckett, A. J. R., Punjabi, V., Wesselmann, F. R., Ahmidouch, A., Albayrak, I., Aniol, K. A., Arrington, J., Asaturyan, A., Ates, O., Baghdasaryan, H., Benmokhtar, F., Bertozzi, W., Bimbot, L., Bosted, P., Boeglin, W., Butuceanu, C., Carter, P., Chernenko, S., Christy, E., Commisso, M., Cornejo, J. C., Covrig, S., Danagoulian, S., Daniel, A., Davidenko, A., Day, D., Dhamija, S., Dutta, D., Ent, R., Frullani, S., Fenker, H., Frlez, E., Garibaldi, F., Gaskell, D., Gilad, S., Goncharenko, Y., Hafidi, K., Hamilton, D., Higinbotham, D. W., Hinton, W., Horn, T., Hu, B., Huang, J., Huber, G. M., Jensen, E., Kang, H., Keppel, C., Khandaker, M., King, P., Kirillov, D., Kohl, M., Kravtsov, V., Kumbartzki, G., Li, Y., Mamyan, V., Margaziotis, D. J., Markowitz, P., Marsh, A., Matulenko, Y., Maxwell, J., Mbianda, G., Meekins, D., Melnik, Y., Miller, J., Mkrtchyan, A., Mkrtchyan, H., Moffit, B., Moreno, O., Mulholland, J., Narayan, A., Nuruzzaman, Nedev, S., Piasetzky, E., Pierce, W., Piskunov, N. M., Prok, Y., Ransome, R. D., Razin, D. S., Reimer, P. E., Reinhold, J., Rondon, O., Shabestari, M., Shahinyan, A., Shestermanov, K., Sirca, S., Sitnik, I., Smykov, L., Smith, G., Solovyev, L., Solvignon, P., Subedi, R., Suleiman, R., Tomasi-Gustafsson, E., Vasiliev, A., Vanderhaeghen, M., Veilleux, M., Wojtsekhowski, B. B., Wood, S., Ye, Z., Zanevsky, Y., Zhang, X., Zhang, Y., Zheng, X., and Zhu, L.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton electric to magnetic form factor ratio, $G_{E}/G_{M}$, obtained separately from cross section and polarization transfer measurements. One possible explanation for this difference is a two-photon-exchange (TPEX) contribution. In an effort to search for effects beyond the one-photon-exchange or Born approximation, we report measurements of polarization transfer observables in the elastic $H(\vec{e},e'\vec{p})$ reaction for three different beam energies at a fixed squared momentum transfer $Q^2 = 2.5$ GeV$^2$, spanning a wide range of the virtual photon polarization parameter, $\epsilon$. From these measured polarization observables, we have obtained separately the ratio $R$, which equals $\mu_p G_{E}/G_{M}$ in the Born approximation, and the longitudinal polarization transfer component $P_\ell$, with statistical and systematic uncertainties of $\Delta R \approx \pm 0.01 \mbox{(stat)} \pm 0.013 \mbox{(syst)}$ and $\Delta P_\ell/P^{Born}_{\ell} \approx \pm 0.006 \mbox{(stat)}\pm 0.01 \mbox{(syst)}$. The ratio $R$ is found to be independent of $\epsilon$ at the 1.5% level, while the $\epsilon$ dependence of $P_\ell$ shows an enhancement of $(2.3 \pm 0.6) %$ relative to the Born approximation at large $\epsilon$.
Published: 2010
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20. Pion-induced Drell-Yan processes and the flavor-dependent EMC effect

Author: Dutta, D., Peng, J. -C., Cloet, I. C., and Gaskell, D.
Subjects: Nuclear Experiment, High Energy Physics - Phenomenology, Nuclear Theory
Abstract: Pion-induced Drell-Yan processes are proposed as a potential tool to measure the flavor dependence of the EMC effect, that is, the flavor-dependent modification of quark distributions in the nuclear medium. Existing pionic Drell-Yan data are compared with calculations using a recent model for nuclear quark distributions that incorporates flavor-dependent nuclear effects. While no firm conclusions can yet be drawn, we demonstrate that existing Drell-Yan data seem to imply a flavor dependence of the EMC effect. We highlight how pion-induced Drell-Yan experiments on nuclear targets can access important new aspects of the EMC effect, not probed in deep inelastic scattering, and will therefore provide very stringent constrains for models of nuclear quark distributions. Predictions for possible future pion-induced Drell-Yan experiments are also presented., Comment: 4 pages, 3 figures
Published: 2010
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21. Recoil Polarization Measurements of the Proton Electromagnetic Form Factor Ratio to Q^2 = 8.5 GeV^2

Author: Puckett, A. J. R., Brash, E. J., Jones, M. K., Luo, W., Meziane, M., Pentchev, L., Perdrisat, C. F., Punjabi, V., Wesselmann, F. R., Ahmidouch, A., Albayrak, I., Aniol, K. A., Arrington, J., Asaturyan, A., Baghdasaryan, H., Benmokhtar, F., Bertozzi, W., Bimbot, L., Bosted, P., Boeglin, W., Butuceanu, C., Carter, P., Chernenko, S., Christy, E., Commisso, M., Cornejo, J. C., Covrig, S., Danagoulian, S., Daniel, A., Davidenko, A., Day, D., Dhamija, S., Dutta, D., Ent, R., Frullani, S., Fenker, H., Frlez, E., Garibaldi, F., Gaskell, D., Gilad, S., Gilman, R., Goncharenko, Y., Hafidi, K., Hamilton, D., Higinbotham, D. W., Hinton, W., Horn, T., Hu, B., Huang, J., Huber, G. M., Jensen, E., Keppel, C., Khandaker, M., King, P., Kirillov, D., Kohl, M., Kravtsov, V., Kumbartzki, G., Li, Y., Mamyan, V., Margaziotis, D. J., Marsh, A., Matulenko, Y., Maxwell, J., Mbianda, G., Meekins, D., Melnik, Y., Miller, J., Mkrtchyan, A., Mkrtchyan, H., Moffit, B., Moreno, O., Mulholland, J., Narayan, A., Nedev, S., Nuruzzaman, Piasetzky, E., Pierce, W., Piskunov, N. M., Prok, Y., Ransome, R. D., Razin, D. S., Reimer, P., Reinhold, J., Rondon, O., Shabestari, M., Shahinyan, A., Shestermanov, K., Sirca, S., Sitnik, I., Smykov, L., Smith, G., Solovyev, L., Solvignon, P., Subedi, R., Tomasi-Gustafsson, E., Vasiliev, A., Veilleux, M., Wojtsekhowski, B. B., Wood, S., Ye, Z., Zanevsky, Y., Zhang, X., Zhang, Y., Zheng, X., and Zhu, L.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: Among the most fundamental observables of nucleon structure, electromagnetic form factors are a crucial benchmark for modern calculations describing the strong interaction dynamics of the nucleon's quark constituents; indeed, recent proton data have attracted intense theoretical interest. In this letter, we report new measurements of the proton electromagnetic form factor ratio using the recoil polarization method, at momentum transfers Q2=5.2, 6.7, and 8.5 GeV2. By extending the range of Q2 for which GEp is accurately determined by more than 50%, these measurements will provide significant constraints on models of nucleon structure in the non-perturbative regime.
Published: 2010
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22. Angular dependence of recoil proton polarization in high-energy \gamma d \to p n

Author: Jiang, X., Arrington, J., Benmokhtar, F., Camsonne, A., Chen, J. P., Choi, S., Chudakov, E., Cusanno, F., Deur, A., Dutta, D., Garibaldi, F., Gaskell, D., Gayou, O., Gilman, R., Glashauser, C., Hamilton, D., Hansen, O., Higinbotham, D. W., Holt, R. J., de Jager, C. W., Jones, M. K., Kaufman, L. J., Kinney, E. R., Kramer, K., Lagamba, L., de Leo, R., Lerose, J., Lhuillier, D., Lindgren, R., Liyanage, N., McCormick, K., Meziani, Z. -E., Michaels, R., Moffit, B., Monaghan, P., Nanda, S., Paschke, K. D., Perdrisat, C. F., Punjabi, V., Qattan, I. A., Ransome, R. D., Reimer, P. E., Reitz, B., Saha, A., Schulte, E. C., Sheyor, R., Slifer, K., Solvignon, P., Sulkosky, V., Urciuoli, G. M., Voutier, E., Wang, K., Wijesooriya, K., Wojtsekhowski, B., and Zhu, L.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: We measured the angular dependence of the three recoil proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily.. Transverse polarizations are not well described, but suggest isovector dominance., Comment: 5 pages, 1 figure, submitted to Physical Review Letters
Published: 2007
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23. Science Requirements and Detector Concepts for the Electron-Ion Collider: EIC Yellow Report

Author: Abdul Khalek, R., Accardi, A., Adam, J., Adamiak, D., Akers, W., Albaladejo, M., Al-bataineh, A., Alexeev, M. G., Ameli, F., Antonioli, P., Armesto, N., Armstrong, W. R., Arratia, M., Arrington, J., Asaturyan, A., Asai, M., Aschenauer, E. C., Aune, S., Avagyan, H., Ayerbe Gayoso, C., Azmoun, B., Bacchetta, A., Baker, M. D., Barbosa, F., Barion, L., Barish, K. N., Barry, P. C., Battaglieri, M., Bazilevsky, A., Behera, N. K., Benmokhtar, F., Berdnikov, V. V., Bernauer, J. C., Bertone, V., Bhattacharya, S., Bissolotti, C., Boer, D., Boglione, M., Bondì, M., Boora, P., Borsa, I., Bossù, F., Bozzi, G., Brandenburg, J. D., Brei, N., Bressan, A., Brooks, W. K., Bufalino, S., Bukhari, M. H. S., Burkert, V., Buttimore, N. H., Camsonne, A., Celentano, A., Celiberto, F. G., Chang, W., Chatterjee, C., Chen, K., Chetry, T., Chiarusi, T., Chien, Y. -T., Chiosso, M., Chu, X., Chudakov, E., Cicala, G., Cisbani, E., Cloet, I. C., Cocuzza, C., Cole, P. L., Colella, D., Collins II, J. L., Constantinou, M., Contalbrigo, M., Contin, G., Corliss, R., Cosyn, W., Courtoy, A., Crafts, J., Cruz-Torres, R., Cuevas, R. C., D'Alesio, U., Dalla Torre, S., Das, D., Dasgupta, S. S., Da Silva, C., Deconinck, W., Defurne, M., Degraw, W., Dehmelt, K., Del Dotto, A., Delcarro, F., Deshpande, A., Detmold, W., De Vita, R., Diefenthaler, M., Dilks, C., Dixit, D. U., Dulat, S., Dumitru, A., Dupré, R., Durham, J. M., Echevarria, M. G., El Fassi, L., Elia, D., Ent, R., Esha, R., Ethier, J. J., Evdokimov, O., Eyser, K. O., Fanelli, C., Fatemi, R., Fazio, S., Fernandez-Ramirez, C., Finger, M., M. Finger Jr., Fitzgerald, D., Flore, C., Frederico, T., Friščić, I., Fucini, S., Furletov, S., Furletova, Y., Gal, C., Gamberg, L., Gao, H., Garg, P., Gaskell, D., Gates, K., Gay Ducati, M. B., Gericke, M., Gil da Silveira, G., Girod, F. -X., Glazier, D. I., Gnanvo, K., Goncalves, V. P., Gonella, L., Gonzalez Hernandez, J. O., Goto, Y., Grancagnolo, F., Greiner, L. C., Guryn, W., Guzey, V., Hatta, Y., Hattawy, M., Hauenstein, F., He, X., Hemmick, T. K., Hen, O., Heyes, G., Higinbotham, D. W., Hiller Blin, A. N., Hobbs, T. J., Hohlmann, M., Horn, T., Hou, T. -J., Huang, J., Huang, Q., Huber, G. M., Hyde, C. E., Iakovidis, G., Ilieva, Y., Jacak, B. V., Jacobs, P. M., Jadhav, M., Janoska, Z., Jentsch, A., Jezo, T., Jing, X., Jones, P. G., Joo, K., Joosten, S., Kafka, V., Kalantarians, N., Kalicy, G., Kang, D., Kang, Z. B., Kauder, K., Kay, S. J. D., Keppel, C. E., Kim, J., Kiselev, A., Klasen, M., Klein, S., Klest, H. T., Korchak, O., Kostina, A., Kotko, P., Kovchegov, Y. V., Krelina, M., Kuleshov, S., Kumano, S., Kumar, K. S., Kumar, R., Kumar, L., Kumerički, K., Kusina, A., Kutak, K., Lai, Y. S., Lalwani, K., Lappi, T., Lauret, J., Lavinsky, M., Lawrence, D., Lednicky, D., Lee, C., Lee, K., Lee, S. H., Levorato, S., Li, H., Li, S., Li, W., Li, X., W. B., Li, Ligonzo, T., Liu, H., Liu, M. X., Liu, X., Liuti, S., Liyanage, N., Lorcé, C., Lu, Z., Lucero, G., Lukow, N. S., Lunghi, E., Majka, R., Makris, Y., Mandjavidze, I., Mantry, S., Mäntysaari, H., Marhauser, F., Markowitz, P., Marsicano, L., Mastroserio, A., Mathieu, V., Mehtar-Tani, Y., Melnitchouk, W., Mendez, L., Metz, A., Meziani, Z. -E., Mezrag, C., Mihovilovič, M., Milner, R., Mirazita, M., Mkrtchyan, H., Mkrtchyan, A., Mochalov, V., Moiseev, V., Mondal, M. M., Morreale, A., Morrison, D., Motyka, L., Moutarde, H., Muñoz Camacho, C., Murgia, F., Murray, M. J., Musico, P., Nadel-Turonski, P., Nadolsky, P. M., Nam, J., Newman, P. R., Neyret, D., Nguyen, D., Nocera, E. R., Noferini, F., Noto, F., Nunes, A. S., Okorokov, V. A., Olness, F., Osborn, J. D., Page, B. S., Park, S., Parker, A., Paschke, K., Pasquini, B., Paukkunen, H., Paul, S., Pecar, C., Pegg, I. L., Pellegrino, C., Peng, C., Pentchev, L., Perrino, R., Petriello, F., Petti, R., Pilloni, A., Pinkenburg, C., Pire, B., Pisano, C., Pitonyak, D., Poblaguev, A. A., Polakovic, T., Posik, M., Potekhin, M., Preghenella, R., Preins, S., Prokudin, A., Pujahari, P., Purschke, M. L., Pybus, J. R., Radici, M., Rajput-Ghoshal, R., Reimer, P. E., Rinaldi, M., Ringer, F., Roberts, C. D., Rodini, S., Rojo, J., Romanov, D., Rossi, P., Santopinto, E., Sarsour, M., Sassot, R., Sato, N., Schenke, B., Schmidke, W. B., Schmidt, I., Schmidt, A., Schmookler, B., Schnell, G., Schweitzer, P., Schwiening, J., Scimemi, I., Scopetta, S., Segovia, J., Seidl, R., Sekula, S., Semenov-Tian-Shanskiy, K., Shao, D. Y., Sherrill, N., Sichtermann, E., Siddikov, M., Signori, A., Singh, B. K., Širca, S., Slifer, K., Slominski, W., Sokhan, D., Sondheim, W. E., Song, Y., Soto, O., Spiesberger, H., Stasto, A. M., Stepanov, P., Sterman, G., Stevens, J. R., Stewart, I. W., Strakovsky, I., Strikman, M., Sturm, M., Stutzman, M. L., Sullivan, M., Surrow, B., Svihra, P., Syritsyn, S., Szczepaniak, A., Sznajder, P., Szumila-Vance, H., Szymanowski, L., Tadepalli, A. S., Tapia Takaki, J. D., Tassielli, G. F., Terry, J., Tessarotto, F., Tezgin, K., Tomasek, L., Torales Acosta, F., Tribedy, P., Tricoli, A., Triloki, Tripathi, S., Trotta, R. L., Tsai, O. D., Tu, Z., Tuvè, C., Ullrich, T., Ungaro, M., Urciuoli, G. M., Valentini, A., Vancura, P., Vandenbroucke, M., Van Hulse, C., Varner, G., Venugopalan, R., Vitev, I., Vladimirov, A., Volpe, G., Vossen, A., Voutier, E., Wagner, J., Wallon, S., Wang, H., Wang, Q., Wang, X., Wei, S. Y., Weiss, C., Wenaus, T., Wennlöf, H., Wickramaarachchi, N., Wikramanayake, A., Winney, D., Wong, C. P., Woody, C., Xia, L., Xiao, B. W., Xie, J., Xing, H., Q. H., Xu, Zhang, J., Zhang, S., Zhang, Z., Zhao, Z. W., Zhao, Y. X., Zheng, L., Zhou, Y., Zurita, P., (Astro)-Particles Physics, 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), CPHT, CNRS, École Polytechnique, Institut Polytechnique de Paris, F-91128 Palaiseau, France, and Pire, Bernard
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Experiment, Nuclear Theory, FOS: Physical sciences, Instrumentation and Detectors (physics.ins-det), [PHYS.HPHE] Physics [physics]/High Energy Physics - Phenomenology [hep-ph], Nuclear Theory (nucl-th), High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], SDG 7 - Affordable and Clean Energy, Nuclear Experiment (nucl-ex)
Abstract: This report describes the physics case, the resulting detector requirements, and the evolving detector concepts for the experimental program at the Electron-Ion Collider (EIC). The EIC will be a powerful new high-luminosity facility in the United States with the capability to collide high-energy electron beams with high-energy proton and ion beams, providing access to those regions in the nucleon and nuclei where their structure is dominated by gluons. Moreover, polarized beams in the EIC will give unprecedented access to the spatial and spin structure of the proton, neutron, and light ions. The studies leading to this document were commissioned and organized by the EIC User Group with the objective of advancing the state and detail of the physics program and developing detector concepts that meet the emerging requirements in preparation for the realization of the EIC. The effort aims to provide the basis for further development of concepts for experimental equipment best suited for the science needs, including the importance of two complementary detectors and interaction regions. This report consists of three volumes. Volume I is an executive summary of our findings and developed concepts. In Volume II we describe studies of a wide range of physics measurements and the emerging requirements on detector acceptance and performance. Volume III discusses general-purpose detector concepts and the underlying technologies to meet the physics requirements. These considerations will form the basis for a world-class experimental program that aims to increase our understanding of the fundamental structure of all visible matter, 902 pages, 415 authors, 151 institutions
Published: 2022

24. Ruling out Color Transparency in Quasielastic $^{12}$C(e,e'p) up to $Q^2$ of 14.2 (GeV/c)$^2$

Author: Bhetuwal, D., Matter, J., Szumila-Vance, H., Kabir, M. L., Dutta, D., Ent, R., Abrams, D., Ahmed, Z., Aljawrneh, B., Alsalmi, S., Ambrose, R., Androic, D., Armstrong, W., Asaturyan, A., Assumin-Gyimah, K., Gayoso, C. Ayerbe, Bandari, A., Basnet, S., Berdnikov, V., Bhatt, H., Biswas, D., Boeglin, W. U., Bosted, P., Brash, E., Bukhari, M. H. S., Chen, H., Chen, J. P., Chen, M., Christy, E. M., Covrig, S., Craycraft, K., Danagoulian, S., Day, D., Diefenthaler, M., Dlamini, M., Dunne, J., Duran, B., Evans, R., Fenker, H., Fomin, N., Fuchey, E., Gaskell, D., Gautam, T. N., Gonzalez, F. A., Hansen, J. O., Hauenstein, F., Hernandez, A. V., Horn, T., Huber, G. M., Jones, M. K., Joosten, S., Karki, A., Keppel, C., Khanal, A., King, P. M., Kinney, E., Ko, H. S., Kohl, M., Lashley-Colthirst, N., Li, S., Li, W. B., Liyanage, A. H., Mack, D., Malace, S., Markowitz, P., Meekins, D., Michaels, R., Mkrtchyan, A., Mkrtchyan, H., Nazeer, S. J., Nanda, S., Niculescu, G., Niculescu, I., Nguyen, D., Nuruzzaman, Pandey, B., Park, S., Pooser, E., Puckett, A., Rehfuss, M., Reinhold, J., Santiesteban, N., Sawatzky, B., Smith, G. R., Sun, A., Tadevosyan, V., Trotta, R., Wood, S. A., Yero, C., Zhang, J., Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and Hall C
Subjects: Nuclear Theory, carbon: target, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], FOS: Physical sciences, color: transparency, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], High Energy Physics - Experiment, Nuclear Theory (nucl-th), High Energy Physics - Experiment (hep-ex), [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], p: recoil, Nuclear Experiment (nucl-ex), Nuclear Experiment, yield: measured, Nuclear Physics, nucleus: target, electron nucleus: scattering, momentum transfer, p: momentum, inelastic scattering, impulse approximation: plane wave, quantum chromodynamics: effect, nucleus: transparency, experimental results, Jefferson Lab
Abstract: Quasielastic $^{12}$C$(e,e'p)$ scattering was measured at space-like 4-momentum transfer squared $Q^2$~=~8, 9.4, 11.4, and 14.2 (GeV/c)$^2$, the highest ever achieved to date. Nuclear transparency for this reaction was extracted by comparing the measured yield to that expected from a plane-wave impulse approximation calculation without any final state interactions. The measured transparency was consistent with no $Q^2$ dependence, up to proton momenta of 8.5~GeV/c, ruling out the quantum chromodynamics effect of color transparency at the measured $Q^2$ scales in exclusive $(e,e'p)$ reactions. These results impose strict constraints on models of color transparency for protons., 5 pages, 2 figures
Published: 2021

25. Parity-violating inelastic electron-proton scattering at low Q2 above the resonance region

Author: Androić, D., Armstrong, D. S., Asaturyan, A., Bartlett, K., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cornejo, J. C., Covrig Dusa, S., Dalton, M. M., Davis, C. A., Deconinck, W., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Elaasar, M., Falk, W. R., Finn, J. M., Gal, C., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Jones, D., Jones, M. K., Jones, R. T., Kargiantoulakis, M., King, P. M., Korkmaz, E., Kowalski, S., Leacock, J., Leckey, J. P., Lee, A. R., Lee, J. H., Lee, L., MacEwan, S., Mack, D., Magee, J. A., Mammei, J., Martin, J. W., McHugh, M. J., Meekins, D., Mesick, K. E., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Narayan, A., Ndukum, L. Z., Nelyubin, V., van Oers, W. T. H., Owen, V. F., Page, S. A., Pan, J., Paschke, K. D., Phillips, S. K., Pitt, M. L., Radloff, R. W., Ramsay, W. D., Roche, J., Sawatzky, B., Seva, T., Shabestari, M. H., Silwal, R., Simicevic, N., Smith, G. R., Solvignon, P., Spayde, D. T., Subedi, A., Suleiman, R., Tadevosyan, V., Waidyawansa, B., Wang, P., Wells, S. P., Wood, S. A., Yang, S., Zang, P., and Qweak Collaboration
Subjects: three-body breakup, reaction cross section, helium-3, Photon, media_common.quotation_subject, Nuclear Theory, FOS: Physical sciences, Electron, Inelastic scattering, 01 natural sciences, Asymmetry, Nuclear physics, High Energy Physics - Phenomenology (hep-ph), Proton scattering, 0103 physical sciences, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, media_common, Physics, Elastic scattering, 010308 nuclear & particles physics, Structure function, Parity (physics), NATURAL SCIENCES. Physics, PRIRODNE ZNANOSTI. Fizika, High Energy Physics - Phenomenology, High Energy Physics::Experiment
Abstract: We report the measurement of the parity-violating asymmetry for the inelastic scattering of electrons from the proton, at $Q^2 = 0.082$ GeV$^2$ and $ W = 2.23$ GeV, above the resonance region. The result $A_{\rm Inel} = - 13.5 \pm 2.0 ({\rm stat}) \pm 3.9 ({\rm syst})$~ppm agrees with theoretical calculations, and helps to validate the modeling of the $\gamma Z$ interference structure functions $F_1^{\gamma Z}$ and $F_2^{\gamma Z}$ used in those calculations, which are also used for determination of the two-boson exchange box diagram ($\Box_{\gamma Z}$) contribution to parity-violating elastic scattering measurements. A positive parity-violating asymmetry for inclusive $\pi^-$ production was observed, as well as positive beam-normal single-spin asymmetry for scattered electrons and a negative beam-normal single-spin asymmetry for inclusive $\pi^-$ production., Comment: 18 pages, 9 figures, version accepted in Physical Review C
Published: 2020

26. Physics with Positron Beams at Jefferson Lab 12 GeV

Author: Afanasev, A., Albayrak, I., Ali, S., Amaryan, M., D'Angelo, A., Annand, J., Arrington, J., Asaturyan, A., Avakian, H., Averett, T., Barion, L., Battaglieri, M., Bellini, V., Berdnikov, V., Bernauer, J., Biselli, A., Boer, M., Bond��, M., Brinkmann, K. -T., Briscoe, B., Burkert, V., Camsonne, A., Cao, T., Cardman, L., Carmignotto, M., Causse, L., Celentano, A., Chatagnon, P., Ciullo, G., Contalbrigo, M., Day, D., Defurne, M., Diehl, S., Dongwi, B., Dupr��, R., Dutta, D., Ehrhart, M., Elouadrhiri, L., Ent, R., Fernando, I., Filippi, A., Furletova, Y., Gao, H., Gasparian, A., Gaskell, D., Georges, F., Girod, F. -X., Grames, J., Gu, C., Guidal, M., Hamilton, D., Hasell, D., Higinbotham, D., Hoballah, M., Horn, T., Hyde, C., Italiano, A., Kalantarians, N., Kalicy, G., Keller, D., Keppel, C., Kerver, M., King, P., Kinney, E., Ko, H. -S., Kohl, M., Kubarovsky, V., Lanza, L., Lenisa, P., Liyanage, N., Liuti, S., Mamei, J., Marchand, D., Markowitz, P., Marsicano, L., Mazouz, M., McCaughan, M., McKinnon, B., Mihovilovi��, M., Milner, R., Mkrtchyan, A., Mkrtchyan, H., Movsisyan, A., Camacho, C. Mu��oz, Nadel-Turo��s, P., De Napoli, M., Nazeer, J., Niccolai, S., Niculescu, G., Novotny, R., Pappalardo, L., Paremuzyan, R., Pasyuk, E., Patel, T., Pegg, I., Perera, D., Puckett, A., Randazzo, N., Rashad, M., Rathnayake, M., Rizzo, A., Roche, J., Rondon, O., Schmidt, A., Shabestari, M., Sharabian, Y., ��irca, S., Sokhan, D., Somov, A., Sparveris, N., Stepanyan, S., Strakovsky, I., Tadevosyan, V., Tiefenback, M., Trotta, R., De Vita, R., Voskanyan, H., Voutier, E., Wang, R., Wojtsekhowski, B., Wood, S., Zaunick, H. -G., Zhamkochyan, S., Zhang, J., Zhao, S., Zheng, X., Zorn, C., 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), 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 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: exchange: two-photon, beam: polarization, electroweak interaction, Nuclear Theory, nucleon: form factor: electromagnetic, elastic scattering, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], nucleon: generalized parton distribution, High Energy Physics - Experiment, positron: beam, High Energy Physics - Experiment (hep-ex), deeply virtual Compton scattering, lepton: accelerator, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Physics::Accelerator Physics, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), electron: beam, Nuclear Experiment, Jefferson Lab
Abstract: Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental program at the next generation of lepton accelerators. In the context of the Hadronic Physics program at the Jefferson Laboratory (JLab), positron beams are complementary, even essential, tools for a precise understanding of the electromagnetic structure of the nucleon, in both the elastic and the deep-inelastic regimes. For instance, elastic scattering of (un)polarized electrons and positrons off the nucleon allows for a model independent determination of the electromagnetic form factors of the nucleon. Also, the deeply virtual Compton scattering of (un)polarized electrons and positrons allows us to separate unambiguously the different contributions to the cross section of the lepto-production of photons, enabling an accurate determination of the nucleon Generalized Parton Distributions (GPDs), and providing an access to its Gravitational Form Factors. Furthermore, positron beams offer the possibility of alternative tests of the Standard Model through the search of a dark photon or the precise measurement of electroweak couplings. This letter proposes to develop an experimental positron program at JLab to perform unique high impact measurements with respect to the two-photon exchange problem, the determination of the proton and the neutron GPDs, and the search for the $A^{\prime}$ dark photon., Letter-of-Intent to Jefferson Lab PAC46
Published: 2019

27. Measurements of Nonsinglet Moments of the Nucleon Structure Functions and Comparison to Predictions from Lattice QCD for Q^{2}=4 GeV^{2}

Author: Albayrak, I., Mamyan, V., Christy, M. E., Ahmidouch, A., Arrington, J., Asaturyan, A., Bodek, A., Bosted, P., Bradford, R., Brash, E., Bruell, A., Butuceanu, C., Coleman, S. J., Commisso, M., Connell, S. H., Dalton, M. M., Danagoulian, S., Daniel, A., Day, D. B., Dhamija, S., Dunne, J., Dutta, D., Ent, R., Gaskell, D., Gasparian, A., Gran, R., Horn, T., Huang, Liting, Huber, G. M., Jayalath, C., Johnson, M., Jones, M. K., Kalantarians, N., Liyanage, A., Keppel, C. E., Kinney, E., Li, Y., Malace, S., Manly, S., Markowitz, P., Maxwell, J., Mbianda, N. N., McFarland, K. S., Meziane, M., Meziani, Z. E., Mills, G. B., Mkrtchyan, H., Mkrtchyan, A., Mulholland, J., Nelson, J., Niculescu, G., Niculescu, I., Pentchev, L., Puckett, A., Punjabi, V., Qattan, I. A., Reimer, P. E., Reinhold, J., Rodriguez, V. M., Rondon- Aramayo, O., Sakuda, M., Sakumoto, W. K., Segbefia, E., Seva, T., Sick, I., Slifer, K., Smith, G. R., Steinman, J., Solvignon, P., Tadevosyan, V., Tajima, S., Tvaskis, V., Vulcan, W. F., Walton, T., Wesselmann, F. R., Wood, S. A., Ye, Zhihong, and E06-009 Collaboration
Subjects: General Physics, Engineering, E06-009 Collaboration, Nuclear Theory, Physical Sciences, Nuclear Experiment, nucl-ex, nucleon nonsinglet moments, Mathematical Sciences
Abstract: We present extractions of the nucleon nonsinglet moments utilizing new precision data on the deuteron F_{2} structure function at large Bjorken-x determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world datasets on the proton and deuteron at lower x measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the x range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high x data. Moreover, recent exciting developments in lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach that first calculates the quark distributions directly before determining moments.
Published: 2019

28. Unique Access to u-Channel Physics: Exclusive Backward-Angle Omega Meson Electroproduction

Author: Li, WB, Huber, GM, Blok, HP, Gaskell, D, Horn, T, Semenov-Tian-Shansky, K, Pire, B, Szymanowski, L, Laget, J-M, Aniol, K, Arrington, J, Beise, EJ, Boeglin, W, Brash, EJ, Breuer, H, Chang, CC, Christy, ME, Ent, R, Gibson, EF, Holt, RJ, Jin, S, Jones, MK, Keppel, CE, Kim, W, King, PM, Kovaltchouk, V, Liu, J, Lolos, GJ, Mack, DJ, Margaziotis, DJ, Markowitz, P, Matsumura, A, Meekins, D, Miyoshi, T, Mkrtchyan, H, Niculescu, I, Okayasu, Y, Pentchev, L, Perdrisat, C, Potterveld, D, Punjabi, V, Reimer, PE, Reinhold, J, Roche, J, Roos, PG, Sarty, A, Smith, GR, Tadevosyan, V, Tang, LG, Tvaskis, V, Volmer, J, Vulcan, W, Warren, G, Wood, SA, Xu, C, Zheng, X, Jefferson Lab <math xmlns=\\'http://www.w3.org/1998/Math/MathML\\' display=\\'inline\\'><mrow><msub><mrow><mi>F</mi></mrow><mrow><mi>π</mi></mrow></msub></mrow></math> Collaboration, University of Regina (UR), Vrije Universiteit Amsterdam [Amsterdam] (VU), Thomas Jefferson National Accelerator Facility (Jefferson Lab), Catholic University of America, National Research Center 'Kurchatov Institute' (NRC KI), Centre de Physique Théorique [Palaiseau] (CPHT), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), National Center for Nuclear Research [Warsaw] (NCBJ), National Center for Nuclear Research (NCBJ), California State University [Los Angeles] (CAL STATE LA), Argonne National Laboratory [Lemont] (ANL), University of Maryland [College Park], University of Maryland System, California Institute of Technology (CALTECH), 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), College of William and Mary [Williamsburg] (WM), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), 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), Student Lab and Education, and Pire, Bernard
Subjects: Nuclear Theory, electron p: interaction, General Physics and Astronomy, 01 natural sciences, Omega, Mathematical Sciences, collinear [factorization], High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), Engineering, structure function, nucleon: wave function, Nuclear Experiment (nucl-ex), Nuclear Experiment, wave function [nucleon], Quantum chromodynamics, Physics, F<%2Fmi><%2Fmrow>π<%2Fmi><%2Fmrow><%2Fmsub><%2Fmrow><%2Fmath>+Collaboration+[Jefferson+Lab+www.w3.org/1998/Math/MathML" display="inline">Fπ Collaboration [Jefferson Lab $, electroproduction [omega(783)], interaction [electron p], High Energy Physics - Phenomenology, Amplitude, kinematics, Physical Sciences, Nucleon, Quark, Particle physics, General Physics, Meson, [PHYS.NEXP] Physics [physics]/Nuclear Experiment [nucl-ex], FOS: Physical sciences, nonperturbative, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Theory (nucl-th), CLAS, 0103 physical sciences, quantum chromodynamics, ddc:530, SDG 14 - Life Below Water, 010306 general physics, factorization: collinear, scattering amplitude, High Energy Physics::Phenomenology, [PHYS.HPHE] Physics [physics]/High Energy Physics - Phenomenology [hep-ph], omega(783): electroproduction, Baryon, Scattering amplitude, distribution amplitude, electromagnetic, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], High Energy Physics::Experiment$
Abstract: Physical review letters 123(18), 182501 (2019). doi:10.1103/PhysRevLett.123.182501, Backward-angle meson electroproduction above the resonance region, which was previously ignored, is anticipated to offer unique access to the three quark plus sea component of the nucleon wave function. In this Letter, we present the first complete separation of the four electromagnetic structure functions above the resonance region in exclusive ω electroproduction off the proton, ep→e′pω, at central Q2 values of 1.60, 2.45 GeV2, at W=2.21 GeV. The results of our pioneering -u≈-umin study demonstrate the existence of a unanticipated backward-angle cross section peak and the feasibility of full L/T/LT/TT separations in this never explored kinematic territory. At Q2=2.45 GeV2, the observed dominance of σT over σL, is qualitatively consistent with the collinear QCD description in the near-backward regime, in which the scattering amplitude factorizes into a hard subprocess amplitude and baryon to meson transition distribution amplitudes: universal nonperturbative objects only accessible through backward-angle kinematics., Published by APS, College Park, Md.
Published: 2019

29. Measurements of Non-Singlet Moments of the Nucleon Structure Functions and Comparison to Predictions from Lattice QCD for $Q^2 = 4$ $\rm GeV^2$

Author: Albayrak, I., Mamyan, V., Christy, M. E., Ahmidouch, A., Arrington, J., Asaturyan, A., Bodek, A., Bosted, P., Bradford, R., Brash, E., Bruell, A., Butuceanu, C, Coleman, S. J., Commisso, M., Connell, S. H., Dalton, M. M., Danagoulian, S., Daniel, A., Day, D. B., Dhamija, S., Dunne, J., Dutta, D., Ent, R., Gaskell, D., Gasparian, A., Gran, R., Horn, T., Huang, Liting, Huber, G. M., Jayalath, C., Johnson, M., Jones, M. K., Kalantarians, N., Liyanage, A., Keppel, C. E., Kinney, E., Li, Y., Malace, S., Manly, S., Markowitz, P., Maxwell, J., Mbianda, N. N., McFarland, K. S., Meziane, M., Meziani, Z. E., Mills, G. B, Mkrtchyan, H., Mkrtchyan, A., Mulholland, J., Nelson, J., Niculescu, G., Niculescu, I., Pentchev, L., Puckett, A., Punjabi, V., Qattan, I. A., Reimer, P. E., Reinhold, J., Rodriguez, V. M, Rondon-Aramayo, O., Sakuda, M., Sakumoto, W. K., Segbefia, E., Seva, T., Sick, I., Slifer, K., Smith, G. R, Steinman, J., Solvignon, P., Tadevosyan, V., Tajima, S., Tvaskis, V., Smith, G. R., Vulcan, W. F., Walton, T., Wesselmann, F. R, Wood, S. A., and Ye, Zhihong
Subjects: Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: We present extractions of the nucleon non-singlet moments utilizing new precision data on the deuteron $F_2$ structure function at large Bjorken-$x$ determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world data sets on the proton and deuteron at lower $x$ measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the $x$ range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high $x$ data. Moreover, recent exciting developments in Lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach which first calculates the quark distributions directly before determining moments.
Published: 2018
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30. Rosenbluth separation of the $\pi^0$ Electroproduction Cross Section off the Neutron

Author: Mazouz, M., Ahmed, Z., Albataineh, H., Allada, K., Aniol, K.A., Bellini, V., Benali, M., Boeglin, W., Bertin, P., Brossard, M., Camsonne, A., Canan, M., Chandavar, S., Chen, C., Chen, J.P., Defurne, M., de Jager, C.W., de Leo, R., Desnault, C., Deur, A., El Fassi, L., Ent, R., Flay, D., Friend, M., Fuchey, E., Frullani, S., Garibaldi, F., Gaskell, D., Giusa, A., Glamazdin, O., Golge, S., Gomez, J., Hansen, O., Higinbotham, D., Holmstrom, T., Horn, T., Huang, J., Huang, M., Huber, G.M., Hyde, C.E., Iqbal, S., Itard, F., Kang, Ho., Kang, Hy., Kelleher, A., Keppel, C., Koirala, S., Korover, I., Lerose, J.J., Lindgren, R., Long, E., Magne, M., Mammei, J., Margaziotis, D.J., Markowitz, P., Martí Jiménez-Argüello, A., Meddi, F., Meekins, D., Michaels, R., Mihovilovic, M., Muangma, N., Muñoz Camacho, C., Nadel-Turonski, P., Nuruzzaman, N., Paremuzyan, R., Puckett, A., Punjabi, V., Qiang, Y., Rakhman, A., Rashad, M.N.H., Riordan, S., Roche, J., Russo, G., Sabatié, F., Saenboonruang, K., Saha, A., Sawatzky, B., Selvy, L., Shahinyan, A., Sirca, S., Solvignon, P., Sperduto, M.L., Subedi, R., Sulkosky, V., Sutera, C., Tobias, W.A., Urciuoli, G.M., Wang, D., Wojtsekhowski, B., Yao, H., Ye, Z., Zana, L., Zhan, X., Zhang, J., Zhao, B., Zhao, Z., Zheng, X., Zhu, P., Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 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), Jefferson Lab Hall A, Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique de Clermont ( LPC ), Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Université Clermont Auvergne ( UCA ) -Centre National de la Recherche Scientifique ( CNRS ), Département de Physique Nucléaire (ex SPhN) ( DPHN ), Institut de Recherches sur les lois Fondamentales de l'Univers ( IRFU ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Institut de Physique Nucléaire d'Orsay ( IPNO ), Université Paris-Sud - Paris 11 ( UP11 ) -Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), and Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: longitudinal, Nuclear Theory, n: structure function, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], momentum transfer dependence, electron n: scattering, High Energy Physics - Experiment, generalized parton distribution: transversity, [ PHYS.HEXP ] Physics [physics]/High Energy Physics - Experiment [hep-ex], hard exclusive electroproduction, recoil, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], polarization: transverse, [ PHYS.NEXP ] Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment, mesons, flavor, generalized parton distributions, scattering, deuteron: structure function, +electron+deuteron+pi0%22">electron deuteron --> electron deuteron pi0, electron deuteron: deep inelastic scattering, nucleon: generalized parton distribution, photon: polarization, coherence, pi0: electroproduction, High Energy Physics::Experiment, experimental results
Abstract: We report the first longitudinal/transverse separation of the deeply virtual exclusive $\pi^0$ electroproduction cross section off the neutron and coherent deuteron. The corresponding four structure functions $d\sigma_L/dt$, $d\sigma_T/dt$, $d\sigma_{LT}/dt$ and $d\sigma_{TT}/dt$ are extracted as a function of the momentum transfer to the recoil system at $Q^2$=1.75 GeV$^2$ and $x_B$=0.36. The $ed \to ed\pi^0$ cross sections are found compatible with the small values expected from theoretical models. The $en \to en\pi^0$ cross sections show a dominance from the response to transversely polarized photons, and are in good agreement with calculations based on the transversity GPDs of the nucleon. By combining these results with previous measurements of $\pi^0$ electroproduction off the proton, we present a flavor decomposition of the $u$ and $d$ quark contributions to the cross section., Comment: 6 pages, 6 figures, Submitted to Phys. Rev. Lett
Published: 2017

31. Measurements of the Separated Longitudinal Structure Function F_L from Hydrogen and Deuterium Targets at Low Q^2

Author: Tvaskis, V., Tvaskis, A., Niculescu, I., Abbott, D., Adams, G. S., Afanasev, A., Ahmidouch, A., Angelescu, T., Arrington, J., Asaturyan, R., Avery, S., Baker, O. K., Benmouna, N., Berman, B. L., Biselli, A., Blok, H. P., Boeglin, W. U., Bosted, P. E., Brash, E., Breuer, H., Chang, G., Chant, N., Christy, M. E., Connell, S. H., Dalton, M. M., Danagoulian, S., Day, D., Dodario, T., Dunne, J. A., Dutta, D., Khayari, N. El, Ent, R., Fenker, H. C., Frolov, V. V., Gaskell, D., Garrow, K., Gilman, R., Gueye, P., Hafidi, K., Hinton, W., Holt, R. J., Horn, T., Huber, G. M., Jackson, H., Jiang, X., Jones, M. K., Joo, K., Kelly, J. J., Keppel, C. E., Kuhn, J., Kinney, E., Klein, A., Kubarovsky, V., Liang, M., Liang, Y., Lolos, G., Lung, A., Mack, D., Malace, S., Markowitz, P., Mbianda, G., McGrath, E., Mckee, D., McKee, P., Meekins, D. G., Mkrtchyan, H., Moziak, B., Napolitano, J., Navasardyan, T., Niculescu, G., Nozar, M., Ostapenko, T., Papandreou, Z., Potterveld, D., Reimer, P. E., Reinhold, J., Roche, J., Rock, S. E., Schulte, E., Segbefia, E., Smith, C., Smith, G. R., Stoler, P., Tadevosyan, V., Tang, L., Telfeyan, J., Todor, L., Ungaro, M., Uzzle, A., Vidakovic, S., Villano, A., Vulcan, W. F., Wang, M., Warren, G., Wesselmann, F., Wojtsekhowski, B., Wood, S. A., Xu, C., Yan, C., Yuan, L., Zheng, X., Zihlmann, B., and Zhu, H.
Subjects: High Energy Physics - Experiment (hep-ex), Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment, High Energy Physics - Experiment
Abstract: Structure functions, as measured in lepton-nucleon scattering, have proven to be very useful in studying the quark dynamics within the nucleon. However, it is experimentally difficult to separately determine the longitudinal and transverse structure functions, and consequently there are substantially less data available for the longitudinal structure function in particular. Here we present separated structure functions for hydrogen and deuterium at low four--momentum transfer squared, Q^2< 1 GeV^2, and compare these with parton distribution parameterizations and a k_T factorization approach. While differences are found, the parameterizations generally agree with the data even at the very low Q^2 scale of the data. The deuterium data show a smaller longitudinal structure function, and smaller ratio of longitudinal to transverse cross section R, than the proton. This suggests either an unexpected difference in R for the proton and neutron or a suppression of the gluonic distribution in nuclei., 11 pages, 7 figures, 2 data tables
Published: 2016

32. Measurement of the Spectral Function of $^{40}$Ar through the $(e,e^\prime p)$ reaction

Author: Benhar, O., Garibaldi, F., Urciuoli, G. M., Camillo Mariani, Chun-Min Jen, Link, J. M., Pitt, M. L., Day, D. B., Crabb, D. G., Keller, D., Lindgren, R., Liyanage, N., Rondon, O. A., Zhang, J., Higinbotham, D. W., Gaskell, D., Hansen, O., Keppel, C. E., Myers, L., Sawatzky, B., Wood, S., Ankowski, A., Sakuda, M., Giusti, C., Meucci, A., Garvey, G., Jiang, X., Mills, G. B., Souder, P. A., Holmes, R., and Beminiwattha, R.
Subjects: Nuclear Theory (nucl-th), Nuclear Theory, Physics::Instrumentation and Detectors, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: The interpretation of the signals detected by high precision experiments aimed at measuring neutrino oscillations requires an accurate description of the neutrino-nucleus cross sections. One of the key element of the analysis is the treatment of nuclear effects, which is one of the main sources of systematics for accelerator based experiments such as the Long Baseline Neutrino Experiment (LBNE). A considerable effort is currently being made to develop theoretical models capable of providing a fully quantitative description of the neutrino-nucleus cross sections in the kinematical regime relevant to LBNE. The approach based on nuclear many-body theory and the spectral function formalism has proved very successful in explaining the available electron scattering data in a variety of kinematical conditions. The first step towards its application to the analysis of neutrino data is the derivation of the spectral functions of nuclei employed in neutrino detectors, in particular argon. We propose a measurement of the coincidence $(e,e^\prime p)$ cross section on argon. This data will provide the experimental input indispensable to construct the argon spectral function, thus paving the way for a reliable estimate of the neutrino cross sections. In addition, the analysis of the $(e,e^\prime p)$ data will help a number of theoretical developments, like the description of final-state interactions needed to isolate the initial-state contributions to the observed single-particle peaks, that is also needed for the interpretation of the signal detected in neutrino experiments., 28 pages, 4 figures, Proposal PR12-14-012 submitted to the JLAB PAC 42, July 2014
Published: 2014

33. Probing the Repulsive Core of the Nucleon-Nucleon Interaction via the 4He(e,e'pN) Triple-Coincidence Reaction

Author: Muangma, I. Korover N., Hen, O., Shneor, R., Sulkosky, V., Kelleher, A., Gilad, S., Higinbotham, D. W., Watson, E. Piasetzky J., Wood, S., Rakhman, Abdurahim, Aguilera, P., Ahmed, Z., Albataineh, H., Allada, K., Anderson, B., Anez, D., Aniol, K., Annand, J., Armstrong, W., Arrington, J., Averett, T., Badman, T., Baghdasaryan, H., Bai, X., Beck, A., Beck, S., Bellini, V., Benmokhtar, F., Bertozzi, W., Bittner, J., Boeglin, W., Camsonne, A., Chen, C., Chen, J. -P., Chirapatpimol, K., Cisbani, E., Dalton, M. M., Daniel, A., Day, D., de Jager, C. W., De Leo, R., Deconinck, W., Defurne, M., Flay, D., Fomin, N., Friend, M., Frullani, S., Fuchey, E., Garibaldi, F., Gaskell, D., Gilman, R., Glamazdin, O., Gu, C., Gueye, P., Hamilton, D., Hanretty, C., Hansen, O., Shabestari, M. Hashemi, Holmstrom, T., Huang, M., Iqbal, S., Jin, G., Kalantarians, N., Kang, H., Khandaker, M., LeRose, J., Leckey, J., Lindgren, R., Long, E., Mammei, J., Margaziotis, D. J., Markowitz, P., Jimenez-Arguello, A. Marti, Meekins, D., Meziani, Z., Michaels, R., Mihovilovic, M., Monaghan, P., Camacho, C. Munoz, Norum, B., Nuruzzaman, Pan, K., Phillips, S., Pomerantz, I., Posik, M., Punjabi, V., Qian, X., Qiang, Y., Qiu, X., Reimer, P. E., Riordan, S., Ron, G., Rondon-Aramayo, O., Saha, A., Schulte, E., Selvy, L., Shahinyan, A., Sirca, S., Sjoegren, J., Slifer, K., Solvignon, P., Sparveris, N., Subedi, R., Tireman, W., Wang, D., Weinstein, L. B., Wojtsekhowski, B., Yan, W., Yaron, I., Ye, Z., Zhan, X., Zhang, J., Zhang, Y., Zhao, B., Zhao, Z., Zheng, X., Zhu, P., and Zielinski, R.
Subjects: Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: We studied simultaneously the 4He(e,e'p), 4He(e,e'pp), and 4He(e,e'pn) reactions at Q^2=2 [GeV/c]2 and x_B>1, for a (e,e'p) missing-momentum range of 400 to 830 MeV/c. The knocked-out proton was detected in coincidence with a proton or neutron recoiling almost back to back to the missing momentum, leaving the residual A=2 system at low excitation energy. These data were used to identify two-nucleon short-range correlated pairs and to deduce their isospin structure as a function of missing momentum in a region where the nucleon-nucleon force is expected to change from predominantly tensor to repulsive. Neutron-proton pairs dominate the high-momentum tail of the nucleon momentum distributions, but their abundance is reduced as the nucleon momentum increases beyond ~500 MeV/c. The extracted fraction of proton-proton pairs is small and almost independent of the missing momentum in the range we studied. Our data are compared with ab-initio calculations of two-nucleon momentum distributions in 4He., 6 pages, 2 figures
Published: 2014
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34. Observation of the Λ7He Hypernucleus by the (e, e′K+) Reaction

Author: Nakamura, S. N., Matsumura, A., Okayasu, Y., Ševa, Tomislav, Rodriguez, V. M., Baturin, P., Yuan, L., Acha, A., Ahmidouch, A., Androić, Darko, Asaturyan, A., Asaturyan, R., Baker, O. K., Benmokhtar, F., Bosted, P., Carlini, R., Chen, C., Christy, M., Cole, L., Danagoulian, S., Daniel, A., Dharmawardane, V., Egiyan, K., Elaasar, M., Ent, R., Fenker, H., Fujii, Y., Furić, Miroslav, Gan, L., Gaskell, D., Gasparian, A., Gibson, E. F., Gogami, T., Gueye, P., Han, Y., Hashimoto, O., Hiyama, E., Honda, D., Horn, T., Hu, B., Hungerford, Ed V., Jayalath, C., Jones, M., Johnston, K., Kalantarians, N., Kanda, H., Kaneta, M., Kato, F., Kato, S., Kawama, D., Keppel, C., Lan, K. J., Luo, W., Mack, D., Maeda, K., Malace, S., Margaryan, A., Marikyan, G., Markowitz, P., Maruta, T., Maruyama, N., Miyoshi, T., Mkrtchyan, A., Mkrtchyan, H., Nagao, S., Navasardyan, T., Niculescu, G., Niculescu, M.-I., Nomura, H., Nonaka, K., Ohtani, A., Oyamada, M., Perez, N., Petković, Tomislav, Randeniya, S., Reinhold, J., Roche, J., Sato, Y., Segbefia, E. K., Šimičević, Neven, Smith, G., Song, Y., Sumihama, M., Tadevosyan, V., Takahashi, T., Tang, L., Tsukada, K., Tvaskis, V., Vulcan, W., Wells, S., Wood, S. A., Yan, C., and Zhamkochyan, S.
Subjects: PRIRODNE ZNANOSTI. Fizika, high-resolution kaon spectrometer, hypernucleus, hy, Nuclear Theory, high-resolution kaon spectrometer, hypernucleus, hypernuclear isotriplet, Nuclear Experiment, NATURAL SCIENCES. Physics
Abstract: An experiment with a newly developed high-resolution kaon spectrometer and a scattered electron spectrometer with a novel configuration was performed in Hall C at Jefferson Lab. The ground state of a neutron-rich hypernucleus, Λ7He, was observed for the first time with the (e, e′K+) reaction with an energy resolution of ∼0.6 MeV. This resolution is the best reported to date for hypernuclear reaction spectroscopy. The Λ7He binding energy supplies the last missing information of the A=7, T=1 hypernuclear isotriplet, providing a new input for the charge symmetry breaking effect of the ΛN potential.
Published: 2013

35. Observation of the Helium 7 Lambda hypernucleus by the (e,e'K+) reaction

Author: Nakamura, S. N., Matsumura, A., Okayasu, Y., Seva, T., Rodriguez, V. M., Baturin, P., Yuan, L., Acha, A., Ahmidouch, A., Androic, D., Asaturyan, A., Asaturyan, R., Baker, O. K., Benmokhtar, F., Bosted, P., Carlini, R., Chen, C., Christy, M., Cole, L., Danagoulian, S., Daniel, A., Dharmawardane, V., Egiyan, K., Elaasar, M., Ent, R., Fenker, H., Fujii, Y., Furic, M., Gan, L., Gaskell, D., Gasparian, A., Gibson, E. F., Gogami, T., Gueye, P., Han, Y., Hashimoto, O., Hiyama, E., Honda, D., Horn, T., Hu, B., Hungerford, Ed V., Jayalath, C., Jones, M., Johnston, K., Kalantarians, N., Kanda, H., Kaneta, M., Kato, F., Kato, S., Kawama, D., Keppel, C., Lan, K. J., Luo, W., Mack, D., Maeda, K., Malace, S., Margaryan, A., Marikyan, G., Markowitz, P., Maruta, T., Maruyama, N., Miyoshi, T., Mkrtchyan, A., Mkrtchyan, H., Nagao, S., Navasardyan, T., Niculescu, G., Niculescu, M. -I., Nomura, H., Nonaka, K., Ohtani, A., Oyamada, M., Perez, N., Petkovic, T., Randeniya, S., Reinhold, J., Roche, J., Sato, Y., Segbefia, E. K., Simicevic, N., Smith, G., Song, Y., Sumihama, M., Tadevosyan, V., Takahashi, T., Tang, L., Tsukada, K., Tvaskis, V., Vulcan, W., Wells, S., Wood, S. A., Yan, C., and Zhamkochyan, S.
Subjects: Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: An experiment with a newly developed high-resolution kaon spectrometer (HKS) and a scattered electron spectrometer with a novel configuration was performed in Hall C at Jefferson Lab (JLab). The ground state of a neutron-rich hypernucleus, He 7 Lambda, was observed for the first time with the (e,e'K+) reaction with an energy resolution of ~0.6 MeV. This resolution is the best reported to date for hypernuclear reaction spectroscopy. The he 7 Lambda binding energy supplies the last missing information of the A=7, T=1 hypernuclear iso-triplet, providing a new input for the charge symmetry breaking (CSB) effect of \Lambda N potential., Comment: 5 pages, 4 figures, submitted to PRL
Published: 2012

36. Direct Measurements of the Lifetime of Heavy Hypernuclei

Author: Qiu, X., Tang, L., Margaryan, A., Achenbach, P., Ahmidouch, A., Albayrak, I., Androic, D., Asaturyan, A., Asaturyan, R., Ates, O., Badui, R., Baturin, P., Boeglin, W., Bono, J., Brash, E., Carter, P., Chen, C., Chen, X., Chiba, A., Christy, E., Dalton, M. M., Danagoulian, S., De Leo, R., Doi, D., Elaasar, M., Ent, R., Fenker, H., Fujii, Y., Furic, M., Gabrielyan, M., Gan, L., Garibaldi, F., Gaskell, D., Gasparian, A., Gogami, T., Hashimoto, O., Horn, T., Hu, B., Hungerford, E. V., Jones, M., Kanda, H., Kaneta, M., Kawai, M., Kawama, D., Khanal, H., Kohl, M., Liyanage, A., Luo, W., Maeda, K., Markowitz, P., Maruta, T., Matsumura, A., Maxwell, V., Mkrtchyan, A., Mkrtchyan, H., Nagao, S., Nakamura, S. N., Narayan, A., Neville, C., Niculescu, G., Niculescu, M. I., Nunez, A., Nuruzzaman, Okayasu, Y., Petkovic, T., Pochodzalla, J., Reinhold, J., Rodriguez, V. M., Samanta, C., Sawatzky, B., Seva, T., Shichijo, A., Tadevosyan, V., Taniya, N., Tsukada, K., Veilleux, M., Vulcan, W., Wesselmann, F. R., Wood, S. A., Ya, L., Yamamoto, T., Ye, Z., Yokota, K., Yuan, L., Zhamkochyan, S., and Zhu, L.
Subjects: Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: The lifetime of a Lambda particle embedded in a nucleus (hypernucleus) decreases from that of free Lambda decay due to the opening of the Lambda N to NN weak decay channel. However, it is generally believed that the lifetime of a hypernucleus attains a constant value (saturation) for medium to heavy hypernuclear masses, yet this hypothesis has been difficult to verify. The present paper reports a direct measurement of the lifetime of medium-heavy hypernuclei produced with a photon-beam from Fe, Cu, Ag, and Bi targets. The recoiling hypernuclei were detected by a fission fragment detector using low-pressure multi-wire proportional chambers. The experiment agrees remarkably well with the only previously-measured single-species heavy-hypernucleus lifetime, that of Fe56_Lambda at KEK, and has significantly higher precision. The experiment disagrees with the measured lifetime of an unknown combination of heavy hypernuclei with 180, Comment: This paper has been withdrawn by the authors pending results of an improved analysis method
Published: 2012
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37. Beam-Target Double Spin Asymmetry A_LT in Charged Pion Production from Deep Inelastic Scattering on a Transversely Polarized He-3 Target at 1.4

Author: Huang, J., Allada, K., Dutta, C., Katich, J., Qian, X., Wang, Y., Zhang, Y., Aniol, K., Annand, J. R. M., Averett, T., Benmokhtar, F., Bertozzi, W., Bradshaw, P. C., Bosted, P., Camsonne, A., Canan, M., Cates, G. D., Chen, C., Chen, J. -P., Chen, W., Chirapatpimol, K., Chudakov, E., Cisbani, E., Cornejo, J. C., Cusanno, F., Dalton, M. M., Deconinck, W., de Jager, C. W., De Leo, R., Deng, X., Deur, A., Ding, H., Dolph, P. A. M., Dutta, D., Fassi, L. El, Frullani, S., Gao, H., Garibaldi, F., Gaskell, D., Gilad, S., Gilman, R., Glamazdin, O., Golge, S., Guo, L., Hamilton, D., Hansen, O., Higinbotham, D. W., Holmstrom, T., Huang, M., Ibrahim, H. F., Iodice, M., Jiang, X., Jin, G., Jones, M. K., Kelleher, A., Kim, W., Kolarkar, A., Korsch, W., LeRose, J. J., Li, X., Li, Y., Lindgren, R., Liyanage, N., Long, E., Lu, H. -J., Margaziotis, D. J., Markowitz, P., Marrone, S., McNulty, D., Meziani, Z. -E., Michaels, R., Moffit, B., Camacho, C. Mu��oz, Nanda, S., Narayan, A., Nelyubin, V., Norum, B., Oh, Y., Osipenko, M., Parno, D., Peng, J. C., Phillips, S. K., Posik, M., Puckett, A. J. R., Qiang, Y., Rakhman, A., Ransome, R. D., Riordan, S., Saha, A., Sawatzky, B., Schulte, E., Shahinyan, A., Shabestari, M. H., ��irca, S., Stepanyan, S., Subedi, R., Sulkosky, V., Tang, L. -G., Tobias, A., Urciuoli, G. M., Vilardi, I., Wang, K., Wojtsekhowski, B., Yan, X., Yao, H., Ye, Y., Ye, Z., Yuan, L., Zhan, X., Zhang, Y. -W., Zhao, B., Zheng, X., Zhu, L., Zhu, X., Zong, X., Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and HALL A
Subjects: High Energy Physics - Experiment (hep-ex), High Energy Physics::Lattice, Nuclear Theory, Mathematics::Classical Analysis and ODEs, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract: We report the first measurement of the double-spin asymmetry $A_{LT}$ for charged pion electroproduction in semi\nobreakdash-inclusive deep\nobreakdash-inelastic electron scattering on a transversely polarized $^{3}$He target. The kinematics focused on the valence quark region, $0.16, 6 pages, 2 figures, 1 tables, published in PRL
Published: 2012

38. Polarization components in $��^{0}$ photoproduction at photon energies up to 5.6 GeV

Author: Luo, W., Brash, E. J., Gilman, R., Jones, M. K., Meziane, M., Pentchev, L., Perdrisat, C. F., Puckett, A. J. R., Punjabi, V., Wesselmann, F. R., Ahmidouch, A., Albayrak, I., Aniol, K. A., Arrington, J., Asaturyan, A., Ates, O., Baghdasaryan, H., Benmokhtar, F., Bertozzi, W., Bimbot, L., Bosted, P., Boeglin, W., Butuceanu, C., Carter, P., Chernenko, S., Christy, M. E., Commisso, M., Cornejo, J. C., Covrig, S., Danagoulian, S., Daniel, A., Davidenko, A., Day, D., Dhamija, S., Dutta, D., Ent, R., Frullani, S., Fenker, H., Frlez, E., Garibaldi, F., Gaskell, D., Gilad, S., Goncharenko, Y., Hafidi, K., Hamilton, D., Higinbotham, D. W., Hinton, W., Horn, T., Hu, B., Huang, J., Huber, G. M., Jensen, E., Kang, H., Keppel, C., Khandaker, M., King, P., Kirillov, D., Kohl, M., Kravtsov, V., Kumbartzki, G., Li, Y., Mamyan, V., Margaziotis, D. J., Markowitz, P., Marsh, A., Matulenko, Y., Maxwell, J., Mbianda, G., Meekins, D., Melnik, Y., Miller, J., Mkrtchyan, A., Mkrtchyan, H., Moffit, B., Moreno, O., Mulholland, J., Narayan, A., Nuruzzaman, Nedev, S., Piasetzky, E., Pierce, W., Piskunov, N. M., Prok, Y., Ransome, R. D., Razin, D. S., Reimer, P. E., Reinhold, J., Rondon, O., Shabestari, M., Shahinyan, A., Shestermanov, K., Sirca, S., Sitnik, I., Smykov, L., Smith, G., Solovyev, L., Solvignon, P., Strakovsky, I. I., Subedi, R., Suleiman, R., Tomasi-Gustafsson, E., Vasiliev, A., Veilleux, M., Wood, S., Ye, Z., Zanevsky, Y., Zhang, X., Zhang, Y., Zheng, X., and Zhu, L.
Subjects: Nuclear Theory, FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: We present new data for the polarization observables of the final state proton in the $^{1}H(\vec��,\vec{p})��^{0}$ reaction. These data can be used to test predictions based on hadron helicity conservation (HHC) and perturbative QCD (pQCD). These data have both small statistical and systematic uncertainties, and were obtained with beam energies between 1.8 and 5.6 GeV and for $��^{0}$ scattering angles larger than 75$^{\circ}$ in center-of-mass (c.m.) frame. The data extend the polarization measurements data base for neutral pion photoproduction up to $E_��=5.6 GeV$. The results show non-zero induced polarization above the resonance region. The polarization transfer components vary rapidly with the photon energy and $��^{0}$ scattering angle in c.m. frame. This indicates that HHC does not hold and that the pQCD limit is still not reached in the energy regime of this experiment., 6 pages and 2 figures
Published: 2011
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39. Search for effects beyond the Born approximation in polarization transfer observables in $\vec{e}p$ elastic scattering

Author: Meziane, M., Brash, E. J., Gilman, R., Jones, M. K., Luo, W., Pentchev, L., Perdrisat, C. F., Puckett, A. J. R., Punjabi, V., Wesselmann, F. R., Ahmidouch, A., Albayrak, I., Aniol, K. A., Arrington, J., Asaturyan, A., Ates, O., Baghdasaryan, H., Benmokhtar, F., Bertozzi, W., Bimbot, L., Bosted, P., Boeglin, W., Butuceanu, C., Carter, P., Chernenko, S., Christy, E., Commisso, M., Cornejo, J. C., Covrig, S., Danagoulian, S., Daniel, A., Davidenko, A., Day, D., Dhamija, S., Dutta, D., Ent, R., Frullani, S., Fenker, H., Frlez, E., Garibaldi, F., Gaskell, D., Gilad, S., Goncharenko, Y., Hafidi, K., Hamilton, D., Higinbotham, D. W., Hinton, W., Horn, T., Hu, B., Huang, J., Huber, G. M., Jensen, E., Kang, H., Keppel, C., Khandaker, M., King, P., Kirillov, D., Kohl, M., Kravtsov, V., Kumbartzki, G., Li, Y., Mamyan, V., Margaziotis, D. J., Markowitz, P., Marsh, A., Matulenko, Y., Maxwell, J., Mbianda, G., Meekins, D., Melnik, Y., Miller, J., Mkrtchyan, A., Mkrtchyan, H., Moffit, B., Moreno, O., Mulholland, J., Narayan, A., Nuruzzaman, Nedev, S., Piasetzky, E., Pierce, W., Piskunov, N. M., Prok, Y., Ransome, R. D., Razin, D. S., Reimer, P. E., Reinhold, J., Rondon, O., Shabestari, M., Shahinyan, A., Shestermanov, K., Sirca, S., Sitnik, I., Smykov, L., Smith, G., Solovyev, L., Solvignon, P., Subedi, R., Suleiman, R., Tomasi-Gustafsson, E., Vasiliev, A., Vanderhaeghen, M., Veilleux, M., Wojtsekhowski, B. B., Wood, S., Ye, Z., Zanevsky, Y., Zhang, X., Zhang, Y., Zheng, X., Zhu, L., Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, HALL A, and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)
Subjects: Nuclear Theory (nucl-th), Nuclear Theory, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear Experiment
Abstract: Intensive theoretical and experimental efforts over the past decade have aimed at explaining the discrepancy between data for the proton electric to magnetic form factor ratio, $G_{E}/G_{M}$, obtained separately from cross section and polarization transfer measurements. One possible explanation for this difference is a two-photon-exchange (TPEX) contribution. In an effort to search for effects beyond the one-photon-exchange or Born approximation, we report measurements of polarization transfer observables in the elastic $H(\vec{e},e'\vec{p})$ reaction for three different beam energies at a fixed squared momentum transfer $Q^2 = 2.5$ GeV$^2$, spanning a wide range of the virtual photon polarization parameter, $\epsilon$. From these measured polarization observables, we have obtained separately the ratio $R$, which equals $\mu_p G_{E}/G_{M}$ in the Born approximation, and the longitudinal polarization transfer component $P_\ell$, with statistical and systematic uncertainties of $\Delta R \approx \pm 0.01 \mbox{(stat)} \pm 0.013 \mbox{(syst)}$ and $\Delta P_\ell/P^{Born}_{\ell} \approx \pm 0.006 \mbox{(stat)}\pm 0.01 \mbox{(syst)}$. The ratio $R$ is found to be independent of $\epsilon$ at the 1.5% level, while the $\epsilon$ dependence of $P_\ell$ shows an enhancement of $(2.3 \pm 0.6) %$ relative to the Born approximation at large $\epsilon$.
Published: 2011

40. Scaling of the F2 structure function in nuclei and quark distributions at x1

Author: Fomin, N., Arrington, J., Day, D. B., Gaskell, D., Daniel, A., Seely, J., Asaturyan, R., Benmokhtar, F., Boeglin, W., Boillat, B., Bosted, P., Bruell, A., Bukhari, M. H. S., Christy, M. E., Chudakov, E., Clasie, B., Connell, S. H., Dalton, M. M., Dutta, D., Ent, R., Fassi, L. El, Fenker, H., Filippone, B. W., Garrow, K., Hill, C., Holt, R. J., Horn, T., Jones, M. K., Jourdan, J., Kalantarians, N., Keppel, C. E., Kiselev, D., Kotulla, M., Lindgren, R., Lung, A. F., Malace, S., Markowitz, P., McKee, P., Meekins, D. G., Miyoshi, T., Mkrtchyan, H., Navasardyan, T., Niculescu, G., Okayasu, Y., Opper, A. K., Perdrisat, C., Potterveld, D. H., Punjabi, V., Qian, X., Reimer, P. E., Roche, J., Rodriguez, V. M., Rondon, O., Schulte, E., Segbefia, E., Slifer, K., Smith, G. R., Solvignon, P., Tadevosyan, V., Tajima, S., Tang, L., Testa, G., Trojer, R., Tvaskis, V., Vulcan, W. F., Wasko, C., Wesselmann, F. R., Wood, S. A., Wright, J., and Zheng, X.
Subjects: Nuclear Theory, Nuclear Experiment
Abstract: We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for $x>1$, which is sensitive to short range contributions to the nuclear wave-function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the `super-fast' quarks probed at x>1. The falloff at x>1 is noticeably stronger in ^2H and ^3He, but nearly identical for all heavier nuclei., Comment: 5 pages, 4 figures, to be submitted to physical review
Published: 2010

41. Angular dependence of recoil proton polarization in high-energy ��d \to p n

Author: Jiang, X., Arrington, J., Benmokhtar, F., Camsonne, A., Chen, J. P., Choi, S., Chudakov, E., Cusanno, F., Deur, A., Dutta, D., Garibaldi, F., Gaskell, D., Gayou, O., Gilman, R., Glashauser, C., Hamilton, D., Hansen, O., Higinbotham, D. W., Holt, R. J., de Jager, C. W., Jones, M. K., Kaufman, L. J., Kinney, E. R., Kramer, K., Lagamba, L., de Leo, R., Lerose, J., Lhuillier, D., Lindgren, R., Liyanage, N., McCormick, K., Meziani, Z. -E., Michaels, R., Moffit, B., Monaghan, P., Nanda, S., Paschke, K. D., Perdrisat, C. F., Punjabi, V., Qattan, I. A., Ransome, R. D., Reimer, P. E., Reitz, B., Saha, A., Schulte, E. C., Sheyor, R., Slifer, K., Solvignon, P., Sulkosky, V., Urciuoli, G. M., Voutier, E., Wang, K., Wijesooriya, K., Wojtsekhowski, B., and Zhu, L.
Subjects: Nuclear Theory (nucl-th), High Energy Physics - Experiment (hep-ex), Nuclear Theory, FOS: Physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: We measured the angular dependence of the three recoil proton polarization components in two-body photodisintegration of the deuteron at a photon energy of 2 GeV. These new data provide a benchmark for calculations based on quantum chromodynamics. Two of the five existing models have made predictions of polarization observables. Both explain the longitudinal polarization transfer satisfactorily.. Transverse polarizations are not well described, but suggest isovector dominance., 5 pages, 1 figure, submitted to Physical Review Letters
Published: 2007
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42. Determination of the Charged Pion Form Factor at Q2=1.60 and 2.45 (GeV/c)2

Author: Fpi2 collaboration, Horn, T., Aniol, K., Arrington, J., Barrett, B., Beise, E. J., Blok, H. P., Boeglin, W., Brash, E. J., Breuer, H., Chang, C. C., Christy, M. E., Ent, R., Gaskell, D., Gibson, E., Holt, R. J., Huber, G. M., Jin, S., Jones, M. K., Keppel, C. E., Kim, W., King, P. M., Kovaltchouk, V., Liu, J., Lolos, G. J., Mack, D. J., Margaziotis, D. J., Markowitz, P., Matsumura, A., Meekins, D., Miyoshi, T., Mkrtchyan, H., Niculescu, I., Okayasu, Y., Pentchev, L., Perdrisat, C., Potterveld, D., Punjabi, V., Reimer, P., Reinhold, J., Roche, J., Roos, P. G., Sarty, A., Smith, G. R., Tadevosyan, V., Tang, L. G., Tvaskis, V., Vidakovic, S., Volmer, J., Vulcan, W., Warren, G., Wood, S. A., Xu, C., and Zheng, X.
Subjects: High Energy Physics::Lattice, Nuclear Theory, FOS: Physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract: The H(e,e'pi+)n cross section was measured at four-momentum transfers of Q2=1.60 and 2.45 GeV2 at an invariant mass of the photon nucleon system of W=2.22 GeV. The charged pion form factor (F_pi) was extracted from the data by comparing the separated longitudinal pion electroproduction cross section to a Regge model prediction in which F_pi is a free parameter. The results indicate that the pion form factor deviates from the charge-radius constrained monopole form at these values of Q2 by one sigma, but is still far from its perturbative Quantum Chromo-Dynamics prediction., Comment: 4 pages, 3 figures, submitted to Physical Review Letters
Published: 2006
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43. Quark helicity distributions in the nucleon for up, down, and strange quarks from semi-inclusive deep-inelastic scattering

Author: Airapetian, A., Akopov, N., Avetissian, E., Marianski, B., Marukyan, H., Masoli, F., Mexner, V., Meyners, N., Mikloukho, O., Miller, C. A., Miyachi, Y., Muccifora, V., Nagaitsev, A., Bailey, P., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W. D., Oganessyan, K., Ohsuga, H., Pickert, N., Potashov, S., Potterveld, D. H., Baturin, V., Raithel, M., Reggiani, D., Reimer, P. E., Reischl, A., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubacek, L., Baumgarten, C., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanjiev, I., Savin, I., Scarlett, C., Schafer, A., Schill, C., Schnell, G., Schuler, K. P., Beckmann, M., Schwind, A., Seele, J., Seidl, R., Seitz, B., Shanidze, R., Shearer, C., Shibata, T. A., Shutov, V., Simani, M. C., Sinram, K., Belostotski, S., Stancari, M., Statera, M., Steffens, E., Steijger, J. J. M., Stenzel, H., Stewart, J., Stosslein, U., Tait, P., Tanaka, H., Taroian, S., Bernreuther, S., Tchuiko, B., Terkulov, A., Tkabladze, A., Trzcinski, A., Tytgat, M., Vandenbroucke, A., van der Nat, P., van der Steenhoven, G., Vetterli, M. C., Vikhrov, V., Bianchi, N., Vincter, M. G., Vogel, C., Vogt, M., Volmer, J., Weiskopf, C., Wendland, J., Wilbert, J., Ybeles Smit, G., Yen, S., Zihlmann, B., Blok, H. P., Zohrabian, H., Zupranski, P., HERMES Collaboration, Blumlein, J., Akopov, Z., Bottcher, H., Borissov, A., Borysenko, A., Bouwhuis, M., Brack, J., Brull, A., Bryzgalov, V., Capitani, G. P., Chiang, H. C., Ciullo, G., Amarian, M., Contalbrigo, M., Dalpiaz, P. F., De Leo, R., De Nardo, L., De Sanctis, E., Devitsin, E., Di Nezza, P., Duren, M., Ehrenfried, M., Elalaoui-Moulay, A., Ammosov, V. V., Elbakian, G., Ellinghaus, F., Elschenbroich, U., Ely, J., Fabbri, R., Fantoni, A., Fechtchenko, A., Felawka, L., Fox, B., Franz, J., Andrus, A., Frullani, S., Gapienko, G., Gapienko, V., Garibaldi, F., Garrow, K., Garutti, E., Gaskell, D., Gavrilov, G., Gharibyan, V., Graw, G., Aschenauer, E. C., Grebeniouk, O., Greeniaus, L. G., Gregor, I. M., Hafidi, K., Hartig, M., Hasch, D., Heesbeen, D., Henoch, M., Hertenberger, R., Hesselink, W. H. A., Augustyniak, W., Hillenbrand, A., Hoek, M., Holler, Y., Hommez, B., Iarygin, G., Ivanilov, A., Izotov, A., Jackson, H. E., Jgoun, A., Kaiser, R., Avakian, R., Kinney, E., Kisselev, A., Konigsmann, K., Kopytin, M., Korotkov, V., Kozlov, V., Krauss, B., Krivokhijine, V. G., Lagamba, L., Lapikas, Louk, Avetissian, A., Laziev, A., Lenisa, P., Liebing, P., Lindemann, T., Linden-Levy, L. A., Lipka, K., Lorenzon, W., Lu, J., Maiheu, B., Makins, N. C. R., (Astro)-Particles Physics, Photo Conversion Materials, and Student Lab and Education
Subjects: Quark, internal [polarized target], Nuclear and High Energy Physics, Particle physics, Strange quark, sea [quark], High Energy Physics::Lattice, deep inelastic scattering [positron deuteron], Hadron, Nuclear Theory, dependence [flavor], Down quark, FOS: Physical sciences, HERMES, 01 natural sciences, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), density [helicity], 27.5 GeV, Pion, 0103 physical sciences, ddc:530, SDG 14 - Life Below Water, deep inelastic scattering [positron p], 010306 general physics, electroproduction [pi], Physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, polarization [quark], Deep inelastic scattering, moment, Baryon, DESY HERA Stor, electroproduction [K], Up quark, valence [quark], polarization [cross section], High Energy Physics::Experiment, polarized beam [positron], asymmetry [spin], experimental results
Abstract: Polarized deep-inelastic scattering data on longitudinally polarized hydrogen and deuterium targets have been used to determine double-spin asymmetries of cross sections. Inclusive and semi-inclusive asymmetries for the production of positive and negative pions from hydrogen were obtained in a reanalysis of previously published data. Inclusive and semi-inclusive asymmetries for the production of negative and positive pions and kaons were measured on a polarized deuterium target. The separate helicity densities for the up and down quarks and the anti-up, anti-down, and strange sea quarks were computed from these asymmetries in a "leading order" QCD analysis. The polarization of the up-quark is positive and that of the down-quark is negative. All extracted sea quark polarizations are consistent with zero, and the light quark sea helicity densities are flavor symmetric within the experimental uncertainties. First and second moments of the extracted quark helicity densities in the measured range are consistent with fits of inclusive data. © 2005 The American Physical Society.
Published: 2005

44. Nuclear polarization of molecular hydrogen recombined on a non-metallic surface

Author: Airapetian, A, Akopov, N, Akopov, Z, Amarian, M, Ammosov, Vv, Andrus, A, Aschenauer, Ec, Augustymak, W, Avakian, R, Avetissian, A, Avetissian, E, Bailey, P, Baturin, V, Baumgarten, C, Beckmann, M, Belostotski, S, Bernreuther, S, Bianchi, N, Blok, Hp, Bottcher, H, Borissov, A, Borysenko, A, Bouwhuis, M, Brack, J, Brull, A, Bryzgalov, V, Capitanilo, Gp, Chiang, Hc, Ciullo, Giuseppe, Contalbrigo, Marco, Court, G, Ferretti, Paola, DE LEO, R, DE NARDO, L, DE SANCTIS, E, Devitsin, E, DI NEZZA, P, Duren, M, Ehrenfried, M, ELALAOUI MOULAY, A, Elbakian, G, Ellinghaus, F, Elschenbroich, U, Ely, J, Fabbri, Riccardo, Fantoni, A, Fechtchenko, A, Felawka, L, Fox, B, Franz, J, Frullani, S, Gapienko, G, Gapienko, V, Garibaldi, F, Garrow, K, Garutti, E, Gaskell, D, Gavrilov, G, Gharibyan, V, Graw, G, Grebeniouk, O, Greeniaus, Lg, Gregor, Im, Haeberli, W, Hafidi, K, Hartig, M, Hasch, D, Heesbeen, D, Henoch, M, Hertenberger, R, Hesselink, Wha, Hillenbrand, A, Hoek, M, Holler, Y, Hommez, B, Iarygin, G, Ivanilov, A, Izotov, A, Jackson, He, Jgoun, A, Kaiser, R, Kinney, E, Kisselev, A, Kolster, H, Konigsmann, K, Kopytin, M, Korotkov, V, Kozlov, V, Krauss, B, Krivokhijine, Vg, Lagamba, L, Lapikas, L, Laziev, A, Lenisa, Paolo, Liebing, P, LINDEN LEVY LA, Lipka, K, Lorenzon, W, Lu, J, Maiheu, B, Makins, Ncr, Marianski, B, Marukyan, H, Masoli, Francesco Antonio, Mexner, V, Meyners, N, Mikloukho, O, Miller, Ca, Miyachi, Y, Muccifora, V, Nagaitsev, A, Nappi, E, Naryshkin, Y, Nass, A, Negodaev, M, Nowak, Wd, Oganessyan, K, Ohsuga, H, Pickert, N, Potashov, S, Potterveld, Dh, Raithel, M, Reggiani, Davide, Reimer, Pe, Reischl, A, Reolon, Ar, Riedl, C, Rith, K, Rosner, G, Rostomyan, A, Rubacek, L, Rubin, J, Ryckbosch, D, Salomatin, Y, Sanjiev, I, Savin, I, Scarlett, C, Schill, C, Schnell, G, Schuler, Kp, Schwind, A, Seele, J, Seidl, R, Seitz, B, Shanidze, R, Shearer, C, Shibata, Ta, Shutov, V, Simani, Mc, Sinram, K, Stancari, Michelle Dawn, Statera, Marco, Steffens, E, Steijger, Jjm, Stenzel, H, Stewart, J, Stosslein, U, Tait, P, Tanaka, H, Taroian, S, Tchuiko, B, Terkulov, A, Tkabladze, A, Trzcinski, A, Tytgat, M, Vandenbroucke, A, VAN DER NAT, P, VAN DER STEENHOVEN, G, Vetterli, Mc, Vikhrov, V, Vincter, Mg, Vogel, C, Vogt, M, (Astro)-Particles Physics, Photo Conversion Materials, Student Lab and Education, and Airapetian, A
Subjects: Silicon, Atomic Physics (physics.atom-ph), media_common.quotation_subject, Nuclear Theory, chemistry.chemical_element, FOS: Physical sciences, Asymmetry, Physics - Atomic Physics, Metal, Physics - Chemical Physics, 29.25.Pj - Polarized and other targets, 34. - Atomic and molecular collision processes and interactions, 39.10.+j - Atomic and molecular beam sources and techniques, 13.88.+e - Polarization in interactions and scattering, Molecule, Nuclear Experiment, media_common, chemistry.chemical_classification, Physics, Chemical Physics (physics.chem-ph), Scattering, Polymer, Polarization (waves), Atomic and Molecular Physics, and Optics, chemistry, visual_art, visual_art.visual_art_medium, Atomic physics, Recombination
Abstract: The nuclear polarization of $\mathrm{H}_2$ molecules formed by recombination of nuclear polarized H atoms on the surface of a storage cell initially coated with a silicon-based polymer has been measured by using the longitudinal double-spin asymmetry in deep-inelastic positron-proton scattering. The molecules are found to have a substantial nuclear polarization, which is evidence that initially polarized atoms retain their nuclear polarization when absorbed on this type of surface
Published: 2004

45. Flavor decomposition of the sea quark helicity distributions in the nucleon from semiinclusive deep inelastic scattering

Author: Airapetian, A., Akopov, N., Avetissian, E., Mexner, V., Meyners, N., Mikloukho, O., Miller, C. A., Miyachi, Y., Muccifora, V., Nagaitsev, A., Nappi, E., Naryshkin, Y., Nass, A., Bailey, P., Negodaev, M., Nowak, W.-D., Oganessyan, K., Ohsuga, H., Orlandi, G., Pickert, N., Potashov, S., Potterveld, D. H., Raithel, M., Reggiani, D., Baturin, V., Reimer, P. E., Reischl, A., Reolon, A. R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubacek, L., Ryckbosch, D., Salomatin, Y., Baumgarten, C., Sanjiev, I., Savin, I., Scarlett, C., Schafer, A., Schill, C., Schnell, G., Schuler, K. P., Schwind, A., Seele, J., Seidl, R., Beckmann, M., Seitz, B., Shanidze, R., Shearer, C., Shibata, T.-A., Shutov, V., Simani, M. C., Sinram, K., Stancari, M., Statera, M., Steffens, E., Belostotski, S., Steijger, J. J. M., Stewart, J., Stosslein, U., Tait, P., Tanaka, H., Taroian, S., Tchuiko, B., Terkulov, A., Tkabladze, A., Trzcinski, A., Bernreuther, S., Tytgat, M., Vandenbroucke, A., van der Nat, P., van der Steenhoven, G., Vetterli, M. C., Vikhrov, V., Vincter, M. G., Visser, J., Vogel, C., Vogt, M., Bianchi, N., Volmer, J., Weiskopf, C., Wendland, J., Wilbert, J., Ybeles Smit, G., Yen, S., Zihlmann, B., Zohrabian, H., Zupranski, P., HERMES Collaboration, Blok, H. P., Bottcher, H., Akopov, Z., Borissov, A., Bouwhuis, M., Brack, J., Brull, A., Bryzgalov, V., Capitani, G. P., Chiang, H. C., Ciullo, G., Contalbrigo, M., Dalpiaz, P. F., Amarian, M., De Leo, R., De Nardo, L., De Sanctis, E., Devitsin, E., Di Nezza, P., Duren, M., Ehrenfried, M., Elalaoui-Moulay, A., Elbakian, G., Ellinghaus, F., Ammosov, V. V., Elschenbroich, U., Ely, J., Fabbri, R., Fantoni, A., Fechtchenko, A., Felawka, L., Fox, B., Franz, J., Frullani, S., Garber, Y., Andrus, A., Gapienko, G., Gapienko, V., Garibaldi, F., Garrow, K., Garutti, E., Gaskell, D., Gavrilov, G., Gharibyan, V., Graw, G., Grebeniouk, O., Aschenauer, E. C., Greeniaus, L. G., Hafidi, K., Hartig, M., Hasch, D., Heesbeen, D., Henoch, M., Hertenberger, R., Hesselink, W. H. A., Hillenbrand, A., Hoek, M., Augustyniak, W., Holler, Y., Hommez, B., Iarygin, G., Ivanilov, A., Izotov, A., Jackson, H. E., Jgoun, A., Kaiser, R., Kinney, E., Kisselev, A., Avakian, R., Konigsmann, K., Kopytin, M., Korotkov, V., Kozlov, V., Krauss, B., Krivokhijine, V. G., Lagamba, L., Lapikas, L., Laziev, A., Lenisa, P., Avetissian, A., Liebing, P., Lindemann, T., Lipka, K., Lorenzon, W., Lu, J., Maiheu, B., Makins, N. C. R., Marianski, B., Marukyan, H., and Masoli, F.
Subjects: sea [quark], momentum spectrum [quark], High Energy Physics::Lattice, deep inelastic scattering [positron deuteron], Nuclear Theory, HERMES, absorption [photon], x-dependence, inclusive reaction [positron deuteron], helicity [quark], ddc:550, Nuclear Experiment, 27.6 GeV, High Energy Physics::Phenomenology, DESY HERA Stor, electroproduction [K+], electroproduction [K-], flavor [quark], High Energy Physics::Experiment, asymmetry [flavor], polarized beam [positron], polarized target [deuteron], electroproduction [pi+], asymmetry [spin], electroproduction [pi-], experimental results
Abstract: Double-spin asymmetries of semi-inclusive cross sections for the production of identified pions and kaons have been measured in deep-inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions including those for three sea quark flavors were extracted from these data together with re-analyzed previous data for identified pions from a hydrogen target. These distributions are consistent with zero for all three sea flavors. A recently predicted flavor asymmetry in the polarization of the light quark sea appears to be disfavored by the data.
Published: 2004

46. Evidence for a narrow |S|=1 baryon state at a mass of 1528 MeV in quasi-real photoproduction

Author: Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., Aschenauer, E.C., Augustyniak, W., Avakian, R., Avetissian, A., Avetissian, E., Bailey, P., Balin, D., Baturin, V., Beckmann, M., Belostotski, S., Bernreuther, S., Bianchi, N., Blok, H.P., Bottcher, H., Borissov, A., Borysenko, A., Bouwhuis, M., Brack, J., Brull, A., Bryzgalov, V., Capitani, G.P., Chen, T., Chen, X., Chiang, H.C., Ciullo, G., Contalbrigo, M., Dalpiaz, P.F., Deconinck, W., De Leo, R., De Nardo, L., De Sanctis, E., Devitsin, E., Di Nezza, P., Duren, M., Ehrenfried, M., Elalaoui-Moulay, A., Elbakian, G., Ellinghaus, F., Elschenbroich, U., Ely, J., Fabbri, R., Fantoni, A., Fechtchenko, A., Felawka, L., Fox, B., Frullani, S., Gapienko, G., Gapienko, V., Garibaldi, Y., Garrow, K., Garutti, E., Gaskell, D., Gavrilov, G., Gharibyan, V., Graw, G., Grebeniouk, O., Greeniaus, L.G., Gregor, I.M., Hafidi, K., Hartig, M., Hasch, D., Heesbeen, D., Henoch, M., Hertenberger, R., Hesselink, W.H.A., Hillenbrand, A., Hoek, M., Holler, Y., Hommez, B., Iarygin, G., Ivanilov, A., Izotov, A., Jackson, H.E., Jgoun, A., Kaiser, R., Kinney, E., Kisselev, A., Kopytin, M., Korotkov, V., Kozlov, V., Krauss, B., Krivokhijine, V.G., Lagamba, L., Lapikas, L., Laziev, A., Lenisa, P., Liebing, P., Linden-Levy, L.A., Lipka, K., Lorenzon, W., Lu, H., Lu, J., Lu, S., Lu, X., Ma, B.Q., Maiheu, B., Makins, N.C.R., Mao, Y., Marianski, B., Marukyan, H., Masoli, F., Mexner, V., Meyners, N., Mikloukho, O., Miller, C.A., Miyachi, Y., Muccifora, V., Nagaitsev, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W.D., Oganessyan, K., Ohsuga, H., Pickert, N., Potashov, S., Potterveld, D.H., Raithel, M., Reggiani, D., Reimer, P.E., Reischl, A., Reolon, A.R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubacek, L., Rubin, J., Ryckbosch, D., Salomatin, Y., Sanjiev, I., Savin, I., Schafer, A., Schill, C., Schnell, G., Schuler, K.P., Seele, J., Seidl, R., Seitz, B., Shanidze, R., Shearer, C., Shibata, T.A., Shutov, V., Simani, M.C., Sinram, K., Stancari, M., Statera, M., Steffens, E., Steijger, J.J.M., Stenzel, H., Stewart, J., Stinzing, F., Stosslein, U., Tait, P., Tanaka, H., Taroian, S., Tchuiko, B., Terklov, A., Tkabladze, A., Trzcinski, A., Tytgat, M., Vandenbroucke, A., van der Nat, P., van der Steenhoven, G., Vetterli, M.C., Vikhrov, V., Vincter, M.G., Vogel, C., Vogt, M., Volmer, J., Weiskopf, C., Wendland, J., Wilbert, J., Smit, G.Y., Ye, Y., Ye, Z., Yen, Z., Yu, W., Zihlmann, B., Zohrabian, H., and Zupranski, P.
Subjects: Nuclear Theory, High Energy Physics::Experiment, Nuclear Experiment, QC
Abstract: Evidence for a narrow baryon state is found in quasi-real photoproduction on a deuterium target through the decay channel pK(S)(0) → ppi(+)pi(-). A peak is observed in the pK(S)(0) invariant mass spectrum at 1528 +/- 2.6(stat) +/- 2.1(syst) MeV. Depending on the background model, the naive statistical significance of the peak is 4-6 standard deviations and its width may be somewhat larger than the experimental resolution of sigma = 4.3-6.2 MeV. This state may be interpreted as the predicted S = +1 exotic Theta(+)(uudd (s) over bar) pentaquark baryon. No signal for an hypothetical Theta(++) baryon was observed in the pK(+) invariant mass distribution. The absence of such a signal indicates that an isotensor Theta is excluded and an isovector Theta is unlikely.
Published: 2004

47. Double-spin asymmetries in the cross section of rho /sup 0/ and phi production at intermediate energies

Author: Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., Aschenauer, E.C., Augustyniak, W., Avakian, R., Avetissian, A., Avetissian, E., Bailey, P., Baturin, V., Baumgarten, C., Beckmann, M., Belostotski, S., Bernreuther, S., Bianchi, N., Blok, H.P., Bottcher, H., Borissov, A., Bouwhuis, M., Brack, J., Brull, A., Bryzgalov, V., Capitani, G.P., Chiang, H.C., Ciullo, G., Contalbrigo, M., Court, G.R., Dalpiaz, P.F., De Leo, R., De Nardo, L., De Sanctis, E., Devitsin, E., Di Nezza, P., Duren, M., Ehrenfried, M., Elalaoui-Moulay, A., Elbakian, G., Ellinghaus, F., Elschenbroich, U., Ely, J., Fabbri, R., Fantoni, A., Fechtchenko, A., Felawka, L., Fox, B., Franz, J., Frullani, S., Garber, Y., Gapienko, G., Gapienko, V., Garibaldi, F., Garutti, E., Gaskell, D., Gavrilov, G., Gharibyan, V., Graw, G., Grebeniouk, O., Greeniaus, L.G., Haeberli, W., Hafidi, K., Hartig, M., Hasch, D., Heesbeen, D., Henoch, M., Hertenberger, R., Hesselink, W.H.A., Hillenbrand, A., Holler, Y., Hommez, B., Iarygin, G., Ivanilov, A., Izotov, A., Jackson, H.E., Jgoun, A., Kaiser, R., Kinney, E., Kisselev, A., Konigsmann, K., Kolster, H., Kopytin, M., Korotkov, V., Kozlov, V., Krauss, B., Krivokhijine, V.G., Lagamba, L., Lapikas, L., Laziev, A., Lenisa, P., Liebing, P., Lindemann, T., Lipka, K., Lorenzon, W., Maiheu, B., Makins, N.C.R., Marianski, B., Marukyan, H., Masoli, F., Menden, F., Mexner, V., Meyners, N., Mikloukho, O., Miller, C.A., Miyachi, Y., Muccifora, V., Nagaitsev, A., Nappi, E., Naryshkin, Y., Nass, A., Nowak, W.D., Oganessyan, K., Ohsuga, H., Orlandi, G., Pickert, N., Potashov, S., Potterveld, D.H., Raithel, M., Reggiani, D., Reimer, P., Reischl, A., Reolon, A.R., Rith, K., Rosner, G., Rostomyan, A., Rubacek, L., Ryckbosch, D., Salomatin, Y., Sanjiev, I., Savin, I., Scarlett, C., Schafer, A., Schill, C., Schnell, G., Schuler, K.P., Schwind, A., Seidl, R., Seitz, B., Shanidze, R., Shearer, C., Shibata, T.A., Shutov, V., Simani, M.C., Sinram, K., Stancari, M., Statera, M., Steffens, E., Steijger, J.J.M., Stewart, J., Stosslein, U., Tait, P., Tanaka, H., Taroian, S., Tchuiko, B., Terkulov, A., Thomas, E., Tkabladze, A., Trzcinski, A., Tytgat, M., Urciuoli, G.M., van der Nat, P., van der Steenhoven, G., Van de Vyver, R., Vetterli, M.C., Vikhrov, V., Vincter, M.G., Visser, J., Vogel, C., Vogt, M., Volmer, J., Weiskopf, C., Wendland, J., Wilbert, J., Wise, T., Yen, S., Yoneyama, S., Zihlmann, B., Zohrabian, H., and Zupranski, P.
Subjects: High Energy Physics::Phenomenology, Nuclear Theory, High Energy Physics::Experiment, Nuclear Experiment, QC
Abstract: Double-spin asymmetries in the cross section of electroproduction of rho /sup 0/ and phi mesons on the proton and deuteron are measured at the HERMES experiment. The photoabsorption asymmetry in exclusive rho /sup 0/ electroproduction on the proton exhibits a positive tendency. This is consistent with theoretical predictions that the exchange of an object with unnatural parity contributes to exclusive rho /sup 0/ electroproduction by transverse photons. The photoabsorption asymmetry on the deuteron is found to be consistent with zero. Double-spin asymmetries in rho /sup 0/ and phi meson electroproduction by quasireal photons were also found to be consistent with zero; the asymmetry in the case of the phi meson is compatible with a theoretical prediction which involves ss knockout from the nucleon.
Published: 2003

48. Double-spin asymmetries in the cross section of rho(0) and phi production at intermediate energies

Author: Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V. V., Andrus, A., Aschenauer, E. C., Augustyniak, W., Avakian, R., Avetissian, A., Avetissian, E., Bailey, P., Baturin, V., Baumgarten, C., Beckmann, M., Belostotski, S., Bernreuther, S., Bianchi, N., Blok, H. P., Bottcher, H., Borissov, A., Bouwhuis, M., Brack, J., Brull, A., Bryzgalov, V., Capitani, G. P., Chiang, H. C., Ciullo, Giuseppe, Contalbrigo, Marco, Court, G. R., Ferretti, Paola, De Leo, R., De Nardo, L., De Sanctis, E., Devitsin, E., Di Nezza, P., Duren, M., Ehrenfried, M., Elalaoui Moulay, A., Elbakian, G., Ellinghaus, F., Elschenbroich, U., Ely, J., Fabbri, Riccardo, Fantoni, A., Fechtchenko, A., Felawka, L., Fox, B., Franz, J., Frullani, S., Garber, Y., Gapienko, G., Gapienko, V., Garibaldi, F., Garutti, E., Gaskell, D., Gavrilov, G., Gharibyan, V., Graw, G., Grebeniouk, O., Greeniaus, L. G., Haeberli, W., Hafidi, K., Hartig, M., Hasch, D., Heesbeen, D., Henoch, M., Hertenberger, R., Hesselink, W. H. A., Hillenbrand, A., Holler, Y., Hommez, B., Iarygin, G., Ivanilov, A., Izotov, A., Jackson, H. E., Jgoun, A., Kaiser, R., Kinney, E., Kisselev, A., Konigsmann, Kay C., Kolster, H., Kopytin, M., Korotkov, V., Kozlov, V., Krauss, B., Krivokhijine, V. G., Lagamba, L., Lapikas, L., Laziev, A., Lenisa, Paolo, Liebing, P., Lindemann, T., Lipka, K., Lorenzon, W., Maiheu, B., Makins, N. C. R., Marianski, B., Marukyan, H., Masoli, Francesco Antonio, Menden, F., Mexner, V., Meyners, N., Mikloukho, O., Miller, C. A., Miyachi, Y., Muccifora, V., Nagaitsev, A., Nappi, E., Naryshkin, Y., Nass, A., Nowak, W. D., Oganessyan, K., Ohsuga, H., Orlandi, G., Pickert, N., Potashov, S., Potterveld, D. H., Raithel, M., Reggiani, Davide, Reimer, P., Reischl, A., Reolon, A. R., Rith, K., Rosner, G., Rostomyan, A., Rubacek, L., Ryckbosch, D., Salomatin, Y., Sanjiev, I., Savin, Igor A., Scarlett, C., Schafer, A., Schill, C., Schnell, G., Schuler, K. P., Schwind, A., Seidl, R., Seitz, B., Shanidze, R., Shearer, C., Shibata, T. A., Shutov, V., Simani, M. C., Sinram, K., Stancari, Michelle Dawn, Statera, Marco, Steffens, E., Steijger, J. J. M., Stewart, J., Stosslein, U., Tait, P., Tanaka, H., Taroian, S., Tchuiko, B., Terkulov, A., Thomas, E., Tkabladze, A., Trzcinski, A., Tytgat, M., Urciuoli, G. M., van der Nat, P., van der Steenhoven, G., van de Vyver, R., Vetterli, M. C., Vikhrov, V., Vincter, M. G., Visser, J., Vogel, C., Vogt, M., Volmer, J., Weiskopf, C., Wendland, J., Wilbert, J., Wise, T., Yen, S., Yoneyama, S., Zihlmann, B., Zohrabian, H., Zupranski, P., and (Astro)-Particles Physics
Subjects: HERMES experiment, Particle physics, Photon, Physics and Astronomy (miscellaneous), Meson, media_common.quotation_subject, Nuclear Theory, rho(770) electroproduction, electron p inelastic scattering, electron deuteron inelastic scattering, electron polarized beam, polarized target, Phi(1020) electroproduction, spin asymmetry, x-dependence, momentum transfer dependence, transverse momentum dependence, quark strangeness, quark sea, pomeron exchange, magnetic spectrometer, HERMES experimental results, DESY HERA Stored 27.5 GeV, 01 natural sciences, 7. Clean energy, Asymmetry, High Energy Physics - Experiment, 0103 physical sciences, 010306 general physics, Nuclear Experiment, Engineering (miscellaneous), media_common, Physics, 010308 nuclear & particles physics, High Energy Physics::Phenomenology, Parity (physics), 3. Good health, Deuterium, High Energy Physics::Experiment, Nucleon
Abstract: Double-spin asymmetries in the cross section of electroproduction of $\rho^0$ and $\phi$ mesons on the proton and deuteron are measured at the HERMES experiment. The photoabsorption asymmetry in exclusive $\rho^0$ electroproduction on the proton exhibits a positive tendency. This is consistent with theoretical predictions that the exchange of an object with unnatural parity contributes to exclusive $\rho^0$ electroproduction by transverse photons. The photoabsorption asymmetry on the deuteron is found to be consistent with zero. Double-spin asymmetries in $\rho^0$ and $\phi $ meson electroproduction by quasi-real photons were also found to be consistent with zero; the asymmetry in the case of the $\phi$ meson is compatible with a theoretical prediction which involves $s\bar{s}$ knockout from the nucleon., Comment: 8 pages, 7 figures
Published: 2003

49. Quark fragmentation to pi(+/-), pi(0), K-+/-, p and (p)over-bar in the nuclear environment

Author: Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., Aschenauer, E.C., Augustyniak, W., Avakian, R., Avetissian, A., Avetissian, E., Bailey, P., Baturin, V., Baumgarten, C., Beckmann, M., Belostotski, S., Bernreuther, S., Bianchi, N., Blok, H.P., Bottcher, H., Borissov, A., Borysenko, A., Bouwhuis, M., Brack, J., Brull, A., Bryzgalov, V., Capitani, G.P., Chiang, H.C., Ciullo, G., Contalbrigo, M., Dalpiaz, P.F., De Leo, R., De Nardo, L., De Santis, E., Devitsin, E., Di Nezza, P., Duren, M., Ehrenfried, M., Elalaoui-Moulay, A., Elbakian, G., Ellinghaus, F., Elschenbroich, U., Ely, J., Fabbri, R., Fantoni, A., Fechtchenko, A., Felawka, L., Fox, B., Franz, J., Frullani, S., Gapienko, G., Gapienko, V., Garibaldi, F., Garrow, K., Garutti, E., Gaskell, D., Gavrilov, G., Gharibyan, V., Graw, G., Grebeniouk, O., Greeniaus, L.G., Gregor, I.M., Hafidi, K., Hartig, M., Hasch, D., Heesbeen, D., Henoch, M., Hertenberger, R., Hesselink, W.H.A., Hillenbrand, A., Hoek, M., Holler, Y., Hommez, B., Iarygin, G., Ivanilov, A., Izotov, A., Jackson, H.E., Jgoun, A., Kaiser, R., Kinney, E., Kisselev, A., Konigsmann, K., Kopytin, M., Laziev, A., Lenisa, P., Liebing, P., Lindemann, T., Lipka, K., Lorenzon, W., Lu, J., Maiheu, B., Makins, N.C.R., Marianski, B., Marukyan, H., Masoli, F., Mexner, V., Meyners, N., Mikloukho, O., Miller, C.A., Miyachi, Y., Muccifora, V., Nagaitsev, A., Nappi, E., Naryshkin, Y., Nass, A., Negodaev, M., Nowak, W.D., Oganessyan, K., Ohsuga, H., Pickert, N., Potashov, S., Potterveld, D.H., Raithel, M., Reggiani, D., Reimer, P.E., Reischl, A., Reolon, A.R., Riedl, C., Rith, K., Rosner, G., Rostomyan, A., Rubacek, L., Ryckbosch, D., Salomatin, Y., Sanjiev, I., Savin, I., Scarlett, C., Schafer, A., Schill, C., Schnell, G., Schuler, K.P., Schwind, A., Seele, J., Seidl, R., Seitz, B., Shanidze, R., Shearer, C., Shibata, T.A., Shutov, V., Simani, M.C., Sinram, K., Stancari, M., Statera, M., Steffens, E., Steijger, J.J.M., Stenzel, H., Stewart, J., Stosslein, U., Tait, P., Tanaka, H., Taroian, S., Tchuiko, B., Terkulov, A., Tkabladze, A., Trzcinski, A., Tytgat, M., Vandenbroucke, A., van der Nat, P., van der Steenhoven, G., Vetterli, M.C., Vikhrov, V., Vincter, M.G., Vogel, C., Vogt, M., Volmer, J., Weiskopf, C., Wendland, J., Wilbert, J., Smit, G.Y., Yen, S., Zihlmann, B., Zohrabian, H., and Zupranski, P.
Subjects: High Energy Physics::Phenomenology, Nuclear Theory, High Energy Physics::Experiment, Nuclear Experiment, QC
Abstract: The influence of the nuclear medium on lepto-production of hadrons was studied in the HERMES experiment at DESY in semi- inclusive deep-inelastic scattering of 27.6 GeV positrons off deuterium, nitrogen and krypton targets. The differential multiplicity for krypton relative to that of deuterium has been measured for the first time for various identified hadrons (pi(+), pi(-), pi(0), K+, K-, p and (p) over bar) as a function of the virtual photon energy v, the fraction z of this energy transferred to the hadron, and the hadron transverse momentum squared p(t)(2). The multiplicity ratio is strongly reduced in the nuclear medium at low v and high z, with significant differences among the various hadrons. The distribution of the hadron transverse momentum is broadened towards high p(t)(2) in the nuclear medium, in a manner resembling the Cronin effect previously observed in collisions of heavy ions and protons with nuclei.
Published: 2003

50. Measurement of single-spin azimuthal asymmetries in semi-inclusive electroproduction of pions and kaons on a longitudinally polarised deuterium target

Author: Airapetian, A., Akopov, N., Akopov, Z., Amarian, M., Ammosov, V.V., Andrus, A., Aschenauer, E.C., Augustyniak, W., Avakian, H., Avakian, R., Avetissian, A., Avetissian, E., Bailey, P., Baturin, V., Baumgarten, C., Beckmann, M., Belostotski, S., Bernreuther, S., Bianchi, N., Blok, H.P., Bottcher, H., Borissov, A., Bouwhuis, M., Brack, J., Brull, A., Bryzgalov, V., Capitani, G.P., Chiang, H.C., Ciullo, G., Contalbrigo, M., Court, G.R., Dalpiaz, P.F., De Leo, R., De Nardo, L., De Sanctis, E., Devitsin, E., Di Nezza, P., Duren, M., Ehrenfried, M., Elalaoui-Moulay, A., Elbakian, G., Ellinghaus, F., Eischenbroich, U., Ely, J., Fabbri, R., Fantoni, A., Fechtchenko, A., Felawka, L., Fox, B., Franz, J., Frullani, S., Garber, Y., Gapienko, G., Gapienko, V., Garibaldi, F., Garutti, E., Gaskell, D., Gavrilov, G., Gharibyan, V., Graw, G., Grebeniouk, O., Greeniaus, L.G., Haeberli, W., Hafidi, K., Hartig, M., Hasch, D., Heesbeen, D., Henoch, M., Hertenberger, R., Hesselink, W.H.A., Hillenbrand, A., Holler, Y., Hommez, B., Iarygin, G., Ivanilov, A., Izotov, A., Jackson, H.E., Jgoun, A., Kaiser, R., Kinney, E., Kisselev, A., Konigsmann, K., Kolster, H., Kopytin, M., Korotkov, V., Kozlov, V., Krauss, B., Krivokhijine, V.G., Lagamba, L., Lapikas, L., Laziev, A., Lenisa, P., Liebing, P., Lindemann, T, Lipka, K., Lorenzon, W., Ma, B., Makins, N.C.R., Marukyan, H., Masoli, F., Menden, F., Mexner, V., Meyners, N., Mikloukho, O., Miller, C.A., Miyachi, Y., Muccifora, V., Nagaitsev, A., Nappi, E., Naryshkin, Y., Nass, A., Nowak, W.D., Oganessyan, K., Ohsuga, H., Orlandi, G., Potashov, S., Potterveld, D.H., Raithel, M., Reggiani, D., Reimer, P.E., Reischl, A., Reolon, A.R., Rith, K., Rosner, G., Rostomyan, A., Ryckbosch, D., Sanjiev, I., Savin, I., Scarlett, C., Schafer, A., Schill, C., Schnell, G., Schuler, K.P., Schwind, A., Seidl, R., Seibert, J., Seitz, B., Shanidze, R., Shibata, T., Shutov, V., Simani, M.C., Sinram, K., Stancari, M., Statera, M., Steffens, E., Steijger, J.J.M., Stewart, J., Stosslein, U., Tanaka, H., Taroian, S., Tchuiko, B., Terkulov, A., Tessarin, S., Thomas, E., Tkabladze, A., Trzcinski, A., Tytgat, A., Urciuoli, G.M., van der Nat, P., van der Steenhoven, G., Van de Vyver, R., Vetterli, M.C., Vikhrov, V., Vincter, M.G., Visser, J., Vogel, C., Vogt, M., Volmer, J., Weiskopf, C., Wendland, J., Wilbert, J., Wise, T., Yen, S., Yoneyama, S., Zihlmann, B., Zohrabian, H., Zupranski, P., Photo Conversion Materials, (Astro)-Particles Physics, and Student Lab and Education
Subjects: Nuclear and High Energy Physics, Particle physics, Meson, Nuclear Theory, Hadron, Virtual particle, FOS: Physical sciences, 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), Pion, 13.88.+e, 0103 physical sciences, 010306 general physics, Nuclear Experiment, QC, Spin-½, 13.60.-r, Physics, 010308 nuclear & particles physics, Scattering, High Energy Physics::Phenomenology, Deuterium, 13.87.Fh, 14.20.Dh, Condensed Matter::Strongly Correlated Electrons, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, SDG 6 - Clean Water and Sanitation, Lepton
Abstract: Single-spin asymmetries have been measured for semi-inclusive electroproduction of $\pi^+$, $\pi^-$, $\pi^0$ and $K^+$ mesons in deep-inelastic scattering off a longitudinally polarised deuterium target. The asymmetries appear in the distribution of the hadrons in the azimuthal angle $\phi$ around the virtual photon direction, relative to the lepton scattering plane. The corresponding analysing powers in the $\sin \phi$ moment of the cross section are $0.012 \pm 0.002 {(stat.)} \pm 0.002 {(syst.)}$ for $\pi^+$, $0.006 \pm 0.003 {(stat.)} \pm 0.002 {(syst.)}$ for $\pi^-$, $0.021 \pm 0.005 {(stat.)} \pm 0.003 {(syst.)}$ for $\pi^0$ and $0.013 \pm 0.006 {(stat.)} \pm 0.003 {(syst.)}$ for $K^+$. The $\sin 2\phi$ moments are compatible with zero for all particles., Comment: Revised version shortened 9 pages, 3 tables, 7 figures
Published: 2002
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