Author: "Fuchey, E." / Publication Type: Reports - Searchworks@Jio Institute Digital Library Search Results

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63 results on '"Fuchey, E."'

1. The EMC Effect of Tritium and Helium-3 from the JLab MARATHON Experiment

Author: Abrams, D., Albataineh, H., Aljawrneh, B. S., Alsalmi, S., Androic, D., Aniol, K., Armstrong, W., Arrington, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Beck, A., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Blyth, D., Boeglin, W., Bulumulla, D., Butler, J., Camsonne, A., Carmignotto, M., Castellanos, J., Chen, J. -P., Cloët, I. C., Cohen, E. O., Covrig, S., Craycraft, K., Cruz-Torres, R., Dongwi, B., Duran, B., Dutta, D., Fomin, N., Fuchey, E., Gal, C., Gautam, T. N., Gilad, S., Gnanvo, K., Gogami, T., Gomez, J., Gu, C., Habarakada, A., Hague, T., Hansen, J. -O., Hattawy, M., Hauenstein, F., Higinbotham, D. W., Holt, R. J., Hughes, E. W., Hyde, C., Ibrahim, H., Jian, S., Joosten, S., Karki, A., Karki, B., Katramatou, A. T., Keith, C., Keppel, C., Khachatryan, M., Khachatryan, V., Khanal, A., Kievsky, A., King, D., King, P. M., Korover, I., Kulagin, S. A., Kumar, K. S., Kutz, T., Lashley-Colthirst, N., Li, S., Li, W., Liu, H., Liuti, S., Liyanage, N., Markowitz, P., McClellan, R. E., Meekins, D., Beck, S. Mey-Tal, Meziani, Z. -E., Michaels, R., Mihovilovic, M., Nelyubin, V., Nguyen, D., Nuruzzaman, Nycz, M., Obrecht, R., Olson, M., Owen, V. F., Pace, E., Pandey, B., Pandey, V., Paolone, M., Papadopoulou, A., Park, S., Paul, S., Petratos, G. G., Petti, R., Piasetzky, E., Pomatsalyuk, R., Premathilake, S., Puckett, A. J. R., Punjabi, V., Ransome, R. D., Rashad, M. N. H., Reimer, P. E., Riordan, S., Roche, J., Salmè, G., Santiesteban, N., Sawatzky, B., Scopetta, S., Schmidt, A., Schmookler, B., Segal, J., Segarra, E. P., Shahinyan, A., Širca, S., Sparveris, N., Su, T., Suleiman, R., Szumila-Vance, H., Tadepalli, A. S., Tang, L., Tireman, W., Tortorici, F., Urciuoli, G. M., Wojtsekhowski, B., Wood, S., Ye, Z. H., Ye, Z. Y., and Zhang, J.
Subjects: Nuclear Experiment
Abstract: Measurements of the EMC effect in the tritium and helium-3 mirror nuclei are reported. The data were obtained by the MARATHON Jefferson Lab experiment, which performed deep inelastic electron scattering from deuterium and the three-body nuclei, using a cryogenic gas target system and the High Resolution Spectrometers of the Hall A Facility of the Lab. The data cover the Bjorken $x$ range from 0.20 to 0.83, corresponding to a squared four-momentum transfer $Q^2$ range from 2.7 to $11.9\gevsq$, and to an invariant mass $W$ of the final hadronic state greater than 1.84 GeV/${\it c}^2$. The tritium EMC effect measurement is the first of its kind. The MARATHON experimental results are compared to results from previous measurements by DESY-HERMES and JLab-Hall C experiments, as well as with few-body theoretical predictions., Comment: arXiv admin note: text overlap with arXiv:2104.05850
Published: 2024

2. Quasielastic $\overrightarrow{^{3}\mathrm{He}}(\overrightarrow{e},{e'})$ Asymmetry in the Threshold Region

Author: Nycz, M., Armstrong, W., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Benesch, J., Bhatt, H., Bhetuwal, D., Biswas, D., Camsonne, A., Cates, G., Chen, J-P., Chen, J., Chen, M., Cotton, C., Dalton, M-M., Deltuva, A., Deur, A., Dhital, B., Duran, B., Dusa, S. C., Fernando, I., Fuchey, E., Gamage, B., Gao, H., Gaskell, D., Gautam, T., Gauthier, N., Golak, J., Hansen, J. -O., Hauenstein, F., Henry, W., Higinbotham, D. W., Huber, G., Jantzi, C., Jia, S., Jin, K., Jones, M., Joosten, S., Karki, A., Karki, B., Katugampola, S., Kay, S., Keppel, C., King, E., King, P., Korsch, W., Kumar, V., Li, R., Li, S., Li, W., Mack, D., Malace, S., Markowitz, P., Matter, J., McCaughan, M., Meziani, Z-E., Michaels, R., Mkrtchyan, A., Mkrtchyan, H., Morean, C., Nelyubin, V., Niculescu, G., Niculescu, M., Peng, C., Premathilake, S., Puckett, A., Rathnayake, A., Rehfuss, M., Reimer, P., Riley, G., Roblin, Y., Roche, J., Roy, M., Sauer, P. U., Scopeta, S., Satnik, M., Sawatzky, B., Seeds, S., Širca, S. S., Skibiński, R., Smith, G., Sparveris, N., Szumila-Vance, H., Tadepalli, A., Tadevosyan, V., Tian, Y., Usman, A., Voskanyan, H., Witala, H., Wood, S., Yale, B., Yero, C., Yoon, A., Zhang, J., Zhao, Z., Zheng, X., and Zhou, J.
Subjects: Nuclear Experiment
Abstract: A measurement of the double-spin asymmetry from electron-$^{3}$He scattering in the threshold region of two- and three-body breakup of $^{3}$He was performed at Jefferson Lab, for Q$^{2}$ values of 0.1 and 0.2 (GeV/$c$)$^{2}$. The results of this measurement serve as a stringent test of our understanding of few-body systems. When compared with calculations from plane wave impulse approximation and Faddeev theory, we found that the Faddeev calculations, which use modern nuclear potentials and prescriptions for meson-exchange currents, demonstrate an overall good agreement with data.
Published: 2024

3. 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

4. Inclusive studies of two- and three-nucleon short-range correlations in $^3$H and $^3$He

Author: Li, S., Santiesteban, S. N., Arrington, J., Cruz-Torres, R., Kurbany, L., Abrams, D., Alsalmi, S., Androic, D., Aniol, K., Averett, T., Gayoso, C. Ayerbe, Bane, J., Barcus, S., Barrow, J., Beck, A., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Bulumulla, D., Camsonne, A., Castellanos, J., Chen, J., Chen, J-P., Chrisman, D., Christy, M. E., Clarke, C., Covrig, S., Craycraft, K., Day, D., Dutta, D., Fuchey, E., Gal, C., Garibaldi, F., Gautam, T. N., Gogami, T., Gomez, J., Guéye, P., Habarakada, A., Hague, T. J., Hansen, J. O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holt, R. J., Hyde, C., Itabashi, K., Kaneta, M., Karki, A., Katramatou, A. T., Keppel, C. E., Khachatryan, M., Khachatryan, V., King, P. M., Korover, I., Kutz, T., Lashley-Colthirst, N., Li, W. B., Liu, H., Liyanage, N., Long, E., Mammei, J., Markowitz, P., McClellan, R. E., Meddi, F., Meekins, D., Beck, S. Mey-Tal, Michaels, R., Mihovilovič, M., Moyer, A., Nagao, S., Nelyubin, V., Nguyen, D., Nycz, M., Olson, M., Ou, L., Owen, V., Palatchi, C., Pandey, B., Papadopoulou, A., Park, S., Paul, S., Petkovic, T., Pomatsalyuk, R., Premathilake, S., Punjabi, V., Ransome, R. D., Reimer, P. E., Reinhold, J., Riordan, S., Roche, J., Rodriguez, V. M., Schmidt, A., Schmookler, B., Segarra, E. P., Shahinyan, A., Širca, S., Slifer, K., Solvignon, P., Su, T., Suleiman, R., Szumila-Vance, H., Tang, L., Tian, Y., Tireman, W., Tortorici, F., Toyama, Y., Uehara, K., Urciuoli, G. M., Votaw, D., Williamson, J., Wojtsekhowski, B., Wood, S., Ye, Z. H., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: Inclusive electron scattering at carefully chosen kinematics can isolate scattering from short-range correlations (SRCs), produced through hard, short-distance interactions of nucleons in the nucleus. Because the two-nucleon (2N) SRCs arise from the same N-N interaction in all nuclei, the cross section in the SRC-dominated regime is identical up to an overall scaling factor, and the A/2H cross section ratio is constant in this region. This scaling behavior has been used to identify SRC dominance and to map out the contribution of SRCs for a wide range of nuclei. We examine this scaling behavior at lower momentum transfers using new data on $^2$H, $^3$H, and $^3$He which show that the scaling region is larger than in heavy nuclei. Based on the improved scaling, especially for $^3$H/$^3$He, we examine the ratios at kinematics where three-nucleon SRCs may play an important role. The data for the largest initial nucleon momenta are consistent with isolation of scattering from 3N-SRCs, and suggest that the very-highest momentum nucleons in $^3$He have a nearly isospin-independent momentum configuration, or a small enhancement of the proton distribution.
Published: 2024

5. Electroproduction of the Lambda/Sigma^0 hyperons at Q^2~0.5 (GeV/c)^2 at forward angles

Author: Okuyama, K., Itabashi, K., Nagao, S., Nakamura, S. N., Suzuki, K. N., Gogami, T., Pandey, B., Tang, L., Bydžovský, P., Skoupil, D., Mart, T., Abrams, D., Akiyama, T., Androic, D., Aniol, K., Gayoso, C. Ayerbe, Bane, J., Barcus, S., Barrow, J., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Camsonne, A., Castellanos, J., Chen, J-P., Chen, J., Covrig, S., Chrisman, D., Cruz-Torres, R., Das, R., Fuchey, E., Gnanvo, K., Garibaldi, F., Gautam, T., Gomez, J., Gueye, P., Hague, T. J., Hansen, O., Henry, W., Hauenstein, F., Higinbotham, D. W., Hyde, C. E., Kaneta, M., Keppel, C., Kutz, T., Lashley-Colthirst, N., Li, S., Liu, H., Mammei, J., Markowitz, P., McClellan, R. E., Meddi, F., Meekins, D., Michaels, R., Mihovilovič, M., Moyer, A., Nguyen, D., Nycz, M., Owen, V., Palatchi, C., Park, S., Petkovic, T., Premathilake, S., Reimer, P. E., Reinhold, J., Riordan, S., Rodriguez, V., Samanta, C., Santiesteban, S. N., Sawatzky, B., Širca, S., Slifer, K., Su, T., Tian, Y., Toyama, Y., Uehara, K., Urciuoli, G. M., Votaw, D., Williamson, J., Wojtsekhowski, B., Wood, S. A., Yale, B., Ye, Z., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: In 2018, the E12-17-003 experiment was conducted at the Thomas Jefferson National Accelerator Facility (JLab) to explore the possible existence of an nnLambda state in the reconstructed missing mass distribution from a tritium gas target [K. N. Suzuki et al., Prog. Theor. Exp. Phys. 2022, 013D01 (2022), B. Pandey et al., Phys. Rev. C 105, L051001 (2022)]. As part of this investigation, data was also collected using a gaseous hydrogen target, not only for a precise absolute mass scale calibration but also for the study of Lambda/Sigma^0 electroproduction. This dataset was acquired at Q^2~0.5 (GeV/c)^2, W=2.14 GeV, and theta_{gamma K}^{c.m.}~8 deg. It covers forward angles where photoproduction data is scarce and a low-Q^2 region that is of interest for hypernuclear experiments. On the other hand, this kinematic region is at a slightly higher Q^2 than previous hypernuclear experiments, thus providing crucial information for understanding the Q^2 dependence of the differential cross sections for Lambda/Sigma^0 hyperon electroproduction. This paper reports on the Q^2 dependence of the differential cross section for the e + p -> e' + K^+ + Lambda/Sigma^0 reaction in the 0.2-0.8 (GeV/c)^2, and provides comparisons with the currently available theoretical models., Comment: 11 pages, 15 figures
Published: 2024

6. A novel measurement of the neutron magnetic form factor from A=3 mirror nuclei

Author: Santiesteban, S. N., Li, S., Abrams, D., Alsalmi, S., Androic, D., Aniol, K., Arrington, J., Averett, T., Gayoso, C. Ayerbe, Bane, J., Barcus, S., Barrow, J., Beck, A., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Camsonne, A., Castellanos, J., Chen, J., Chen, J-P., Chrisman, D., Christy, M. E., Clarke, C., Covrig, S., Cruz-Torres, R., Day, D., Dutta, D., Fuchey, E., Gal, C., Garibaldi, F., Gautam, T. N., Gogami, T., Gomez, J., Gueye, P., Hague, T. J., Hansen, J. O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holt, R. J., Hyde, C., Itabashi, K., Kaneta, M., Karki, A., Katramatou, A. T., Keppel, C. E., King, P. M., Kurbany, L., Kutz, T., Lashley-Colthirst, N., Li, W. B., Liu, H., Liyanage, N., Long, E., Lovato, A., Mammei, J., Markowitz, P., McClellan, R. E., Meddi, F., Meekins, D., Michaels, R., Mihovilovic, M., Moyer, A., Nagao, S., Nguyen, D., Nycz, M., Olson, M., Ou, L., Owen, V., Palatchi, C., Pandey, B., Papadopoulou, A., Park, S., Petkovic, T., Premathilake, 6 S., Punjabi, V., Ransome, R. D., Reimer, P. E., Reinhold, J., Riordan, S., Rocco, N., Rodriguez, V. M., Schmidt, A., Schmookler, B., Segarra, E. P., Shahinyan, A., Sirca, S., Slifer, K., Solvignon, P., Su, T., Suleiman, R., Tang, L., Tian, Y., Tireman, W., Tortorici, F., Toyama, Y., Uehara, K., Urciuoli, G. M., Votaw, D., Williamson, J., Wojtsekhowski, B., Wood, S., Ye, Z. H., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei $^3$H and $^3$He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, $0.6
Published: 2023

7. Revealing the short-range structure of the 'mirror nuclei' $^3$H and $^3$He

Author: Li, S., Cruz-Torres, R., Santiesteban, N., Ye, Z. H., Abrams, D., Alsalmi, S., Androic, D., Aniol, K., Arrington, J., Averett, T., Gayoso, C. Ayerbe, Bane, J., Barcus, S., Barrow, J., Beck, A., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Bulumulla, D., Camsonne, A., Castellanos, J., Chen, J., Chen, J-P., Chrisman, D., Christy, M. E., Clarke, C., Covrig, S., Craycraft, K., Day, D., Dutta, D., Fuchey, E., Gal, C., Garibaldi, F., Gautam, T. N., Gogami, T., Gomez, J., Guèye, P., Habarakada, A., Hague, T. J., Hansen, J. O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holt, R. J., Hyde, C., Itabashi, T., Kaneta, M., Karki, A., Katramatou, A. T., Keppel, C. E., Khachatryan, M., Khachatryan, V., King, P. M., Korover, I., Kurbany, L., Kutz, T., Lashley-Colthirst, N., Li, W. B., Liu, H., Liyanage, N., Long, E., Mammei, J., Markowitz, P., McClellan, R. E., Meddi, F., Meekins, D., Beck, S. Mey-Tal, Michaels, R., Mihovilovič, M., Moyer, A., Nagao, S., Nelyubin, V., Nguyen, D., Nycz, M., Olson, M., Ou, L., Owen, V., Palatchi, C., Pandey, B., Papadopoulou, A., Park, S., Paul, S., Petkovic, T., Pomatsalyuk, R., Premathilake, S., Punjabi, V., Ransome, R. D., Reimer, P. E., Reinhold, J., Riordan, S., Roche, J., Rodriguez, V. M., Schmidt, A., Schmookler, B., Segarra, E. P., Shahinyan, A., Slifer, K., Solvignon, P., Širca, S., Su, T., Suleiman, R., Szumila-Vance, H., Tang, L., Tian, Y., Tireman, W., Tortorici, F., Toyama, Y., Uehara, K., Urciuoli, G. M., Votaw, D., Williamson, J., Wojtsekhowski, B., Wood, S., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough together to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly-energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure and mapping out the strength and isospin structure (neutron-proton vs proton-proton pairs) of these virtual excitations is thus critical input for modeling a range of nuclear, particle, and astrophysics measurements. Hitherto measurements used two-nucleon knockout or ``triple-coincidence'' reactions to measure the relative contribution of np- and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurementsshow that SRCs are almost exclusively np pairs, but had limited statistics and required large model-dependent final-state interaction (FSI) corrections. We report on the first measurement using inclusive scattering from the mirror nuclei $^3$H and $^3$He to extract the np/pp ratio of SRCs in the A=3 system. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a dramatic deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for $^3$He and $^3$H. Understanding these results will improve our understanding of the short-range part of the N-N interaction.
Published: 2022
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8. Determination of the titanium spectral function from (e,e'p) data

Author: Jiang, L., Ankowski, A. M., Abrams, D., Gu, L., Aljawrneh, B., Alsalmi, S., Bane, J., Batz, A., Barcus, S., Barroso, M., Bellini, V., Benhar, O., Bericic, J., Biswas, D., Camsonne, A., Castellanos, J., Chen, J. -P., Christy, M. E., Craycraft, K., Cruz-Torres, R., Dai, H., Day, D., Dirican, A., Dusa, S. -C., Fuchey, E., Gautam, T., Giusti, C., Gomez, J., Gu, C., Hague, T. J., Hansen, J. -O., Hauenstein, F., Higinbotham, D. W., Hyde, C., Jerzyk, Z., Johnson, A. M., Keppel, C., Lanham, C., Li, S., Lindgren, R., Liu, H., Mariani, C., McClellan, R. E., Meekins, D., Michaels, R., Mihovilovic, M., Murphy, M., Nguyen, D., Nycz, M., Ou, L., Pandey, B., Pandey, V., Park, K., Perera, G., Puckett, A. J. R., Santiesteban, S. N., Širca, S., Su, T., Tang, L., Tian, Y., Ton, N., Wojtsekhowski, B., Wood, S., Ye, Z., and Zhang, J.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: The E12-14-012 experiment, performed in Jefferson Lab Hall A, has measured the (e,e'p) cross section in parallel kinematics using a natural titanium target. Here, we report the full results of the analysis of the data set corresponding to beam energy 2.2 GeV, and spanning the missing momentum and missing energy range 15 <= pm <= 250 MeV/c and 12 <= Em <= 80 MeV. The reduced cross section has been measured with ~7% accuracy as function of both missing momentum and missing energy. We compared our data to the results of a Monte Carlo simulations performed using a model spectral function and including the effects of final state interactions. The overall agreement between data and simulations is quite good (chi2/d.o.f. = 0.9)., Comment: 6 pages, 4 figures, published in Phys. Rev. D. arXiv admin note: substantial text overlap with arXiv:2203.01748
Published: 2022
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9. Determining the Proton's Gluonic Gravitational Form Factors

Author: Duran, B., Meziani, Z. -E., Joosten, S., Jones, M. K., Prasad, S., Peng, C., Armstrong, W., Atac, H., Chudakov, E., Bhatt, H., Bhetuwal, D., Boer, M., Camsonne, A., Chen, J. -P., Dalton, M. M., Deokar, N., Diefenthaler, M., Dunne, J., Fassi, L. El, Fuchey, E., Gao, H., Gaskell, D., Hansen, O., Hauenstein, F., Higinbotham, D., Jia, S., Karki, A., Keppel, C., King, P., Ko, H. S., Li, X., Li, R., Mack, D., Malace, S., McCaughan, M., McClellan, R. E., Michaels, R., Meekins, D., Paolone, M., Pentchev, L., Pooser, E., Puckett, A., Radloff, R., Rehfuss, M., Reimer, P. E., Riordan, S., Sawatzky, B., Smith, A., Sparveris, N., Szumila-Vance, H., Wood, S., Xie, J., Ye, Z., Yero, C., and Zhao, Z.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: The proton is one of the main building blocks of all visible matter in the universe. Among its intrinsic properties are its electric charge, mass, and spin. These emerge from the complex dynamics of its fundamental constituents, quarks and gluons, described by the theory of quantum chromodynamics (QCD). Using electron scattering, its electric charge and spin, shared among the quark constituents, have been the topic of active investigation. An example is the novel precision measurement of the proton's electric charge radius. In contrast, little is known about the proton's inner mass density, dominated by the energy carried by the gluons, which are hard to access through electron scattering since gluons carry no electromagnetic charge. Here, we chose to probe this gluonic gravitational density using a small color dipole, the $J/\psi$ particle, through its threshold photoproduction. From our data, we determined, for the first time, the proton's gluonic gravitational form factors. We used a variety of models and determined, in all cases, a mass radius that is notably smaller than the electric charge radius. In some cases, the determined radius, although model dependent, is in excellent agreement with first-principle predictions from lattice QCD. This work paves the way for a deeper understanding of the salient role of gluons in providing gravitational mass to visible matter., Comment: Accepted for publication
Published: 2022
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10. First Measurement of the EMC Effect in $^{10}$B and $^{11}$B

Author: Karki, A., Biswas, D., Gonzalez, F. A., Henry, W., Morean, C., Nadeeshani, A., Sun, A., Abrams, D., Ahmed, Z., Aljawrneh, B., Alsalmi, S., Ambrose, R., Androic, D., Armstrong, W., Arrington, J., Asaturyan, A., Assumin-Gyimah, K., Gayoso, C. Ayerbe, Bandari, A., Bane, J., Barrow, J., Basnet, S., Berdnikov, V., Bhatt, H., Bhetuwal, D., Boeglin, W. U., Bosted, P., Brash, E., Bukhari, M. H. S., Chen, H., Chen, J. P., Chen, M., Christy, M. E., Covrig, S., Craycraft, K., Danagoulian, S., Day, D., Diefenthaler, M., Dlamini, M., Dunne, J., Duran, B., Dutta, D., Elliott, C., Ent, R., Fenker, H., Fomin, N., Fuchey, E., Gaskell, D., Gautam, T. N., Hansen, J. O., Hauenstein, F., Hernandez, A. V., Horn, T., Huber, G. M., Jones, M. K., Joosten, S., Kabir, M. L., Kalantarians, N., 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., Matter, J., Meekins, D., Michaels, R., Mkrtchyan, A., Mkrtchyan, H., Nanda, S., Nguyen, D., Niculescu, G., Niculescu, I., Nuruzzaman, Pandey, B., Park, S., Pooser, E., Puckett, A. J. R., Rehfuss, M., Reinhold, J., Santiesteban, N., Sawatzky, B., Smith, G. R., Szumila-Vance, H., Tadepalli, A. S., Tadevosyan, V., Trotta, R., Wood, S. A., Yero, C., and Zhang, J.
Subjects: Nuclear Experiment
Abstract: The nuclear dependence of the inclusive inelastic electron scattering cross section (the EMC effect) has been measured for the first time in $^{10}$B and $^{11}$B. Previous measurements of the EMC effect in $A \leq 12$ nuclei showed an unexpected nuclear dependence; $^{10}$B and $^{11}$B were measured to explore the EMC effect in this region in more detail. Results are presented for $^9$Be, $^{10}$B, $^{11}$B, and $^{12}$C at an incident beam energy of 10.6~GeV. The EMC effect in the boron isotopes was found to be similar to that for $^9$Be and $^{12}$C, yielding almost no nuclear dependence in the EMC effect in the range $A=4-12$. This represents important, new data supporting the hypothesis that the EMC effect depends primarily on the local nuclear environment due to the cluster structure of these nuclei., Comment: To appear in PRC
Published: 2022

11. Constraints on the onset of color transparency from quasi-elastic $^{12}$C$(e,e'p)$ up to $Q^2=\,14.2\,$(GeV$/c)^2$

Author: Bhetuwal, D., Matter, J., Szumila-Vance, H., Gayoso, C. Ayerbe, 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., 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
Abstract: Quasi-elastic scattering on $^{12}$C$(e,e'p)$ was measured in Hall C at Jefferson Lab for space-like 4-momentum transfer squared $Q^2$ in the range of 8--14.2\,(GeV/$c$)$^2$ with proton momenta up to 8.3\,GeV/$c$. The experiment was carried out in the upgraded Hall C at Jefferson Lab. It used the existing high momentum spectrometer and the new super high momentum spectrometer to detect the scattered electrons and protons in coincidence. The nuclear transparency was extracted as the ratio of the measured yield to the yield calculated in the plane wave impulse approximation. Additionally, the transparency of the $1s_{1/2}$ and $1p_{3/2}$ shell protons in $^{12}$C was extracted, and the asymmetry of the missing momentum distribution was examined for hints of the quantum chromodynamics prediction of Color Transparency. All of these results were found to be consistent with traditional nuclear physics and inconsistent with the onset of Color Transparency.
Published: 2022
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12. 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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13. The Proton Spin Structure Function $g_2$ and Generalized Polarizabilities in the Strong QCD Regime

Author: Ruth, D., Zielinski, R., Gu, C., Allada, M., Badman, T., Huang, M., Liu, J., Zhu, P., Allada, K., Zhang, J., Camsonne, A., Chen, J. P., Slifer, K., Aniol, K., Annand, J., Arrington, J., Averett, T., Baghdasaryan, H., Bellini, V., Boeglin, W., Brock, J., Carlin, C., Chen, C., Cisbani, E., Crabb, D., Daniel, A., Day, D., Duve, R., Fassi, L. El, Friedman, M., Fuchey, E., Gao, H., Gilman, R., Glamazdin, S., Gueye, P., Hafez, M., Han, Y., Hansen, O., Shabestari, M. Hashemi, Hen, O., Higinbotham, D., Horn, T., Iqbal, S., Jensen, E., Kang, H., Keith, C. D., Kelleher, A., Keller, D., Khanal, H., Korover, I., Kumbartzki, G., Li, W., Lichtenstadt, J., Lindgren, R., Long, E., Malace, S., Markowitz, P., Maxwell, J., Meekins, D. M., Meziani, Z. E., McLean, C., Michaels, R., Mihovilovic, M., Muangma, N., Camacho, C. Munoz, Musson, J., Myers, K., Oh, Y., Carmignotto, M. Pannunzio, Perdrisat, C., Phillips, S., Piasetzky, E., Pierce, J., Punjabi, V., Qiang, Y., Reimer, P. E., Roblin, Y., Ron, G., Rondon, O., Russo, G., Saenboonruang, K., Sawatzky, B., Shahinyan, A., Shneor, R., Sjoegren, J., Solvignon-Slifer, P., Sparveris, N., Sulkosky, V., Wesselmann, F., Yan, W., Yang, H., Yao, H., Ye, Z., Yurov, M., Zhang, Y., Zhao, Y. X., and Zheng, X.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: The strong interaction is not well understood at low energy, or for interactions with low momentum transfer $Q^2$, but one of the clearest insights we have comes from Chiral Perturbation Theory ($\chi$PT). This effective treatment gives testable predictions for the nucleonic generalized polarizabilities -- fundamental quantities describing the nucleon's response to an external field. We have measured the proton's generalized spin polarizabilities in the region where $\chi$PT is expected to be valid. Our results include the first ever data for the transverse-longitudinal spin polarizability $\delta_{LT}$, and also extend the coverage of the polarizability $\bar{d_2}$ to very low $Q^2$ for the first time. These results were extracted from moments of the structure function $g_2$, a quantity which characterizes the internal spin structure of the proton. Our experiment ran at Jefferson Lab using a polarized electron beam and a polarized solid ammonia (NH$_3$) target. The $\delta_{LT}$ polarizability has remained a challenging quantity for $\chi$PT to reproduce, despite its reduced sensitivity to higher resonance contributions; recent competing calculations still disagree with each other and also diverge from the measured neutron data at very low $Q^2$. Our proton results provide discriminating power between existing calculations, and will help provide a better understanding of this strong QCD regime.
Published: 2022

14. Determination of the argon spectral function from (e,e'p) data

Author: Jiang, L., Ankowski, A. M., Abrams, D., Gu, L., Aljawrneh, B., Alsalmi, S., Bane, J., Batz, A., Barcus, S., Barroso, M., Bellini, V., Benhar, O., Bericic, J., Biswas, D., Camsonne, A., Castellanos, J., Chen, J. -P., Christy, M. E., Craycraft, K., Cruz-Torres, R., Dai, H., Day, D., Dirican, A., Dusa, S. -C., Fuchey, E., Gautam, T., Giusti, C., Gomez, J., Gu, C., Hague, T. J., Hansen, J. -O., Hauenstein, F., Higinbotham, D. W., Hyde, C., Jerzyk, Z., Keppel, C., Li, S., Lindgren, R., Liu, H., Mariani, C., McClellan, R. E., Meekins, D., Michaels, R., Mihovilovic, M., Murphy, M., Nguyen, D., Nycz, M., Ou, L., Pandey, B., Pandey, V., Park, K., Perera, G., Puckett, A. J. R., Santiesteban, S. N., Širca, S., Su, T., Tang, L., Tian, Y., Ton, N., Wojtsekhowski, B., Wood, S., Ye, Z., and Zhang, J.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: The E12-14-012 experiment, performed in Jefferson Lab Hall A, has measured the $(e, e'p)$ cross section in parallel kinematics using a natural argon target. Here, we report the full results of the analysis of the data set corresponding to beam energy 2.222 GeV, and spanning the missing momentum and missing energy range $15 \lesssim p_m \lesssim 300$ MeV/c and $12 \lesssim E_m \lesssim 80$ MeV. The reduced cross section, determined as a function of $p_m$ and $E_m$ with $\approx$4\% accuracy, has been fitted using the results of Monte Carlo simulations involving a model spectral function and including the effects of final state interactions. The overall agreement between data and simulations turns out to be quite satisfactory ($\chi^2$/n.d.o.f.=1.9). The resulting spectral function will provide valuable new information, needed for the interpretation of neutrino interactions in liquid argon detectors., Comment: Published version
Published: 2022
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15. Deeply virtual Compton scattering cross section at high Bjorken $x_B$

Author: Georges, F., Rashad, M. N. H., Stefanko, A., Dlamini, M., Karki, B., Ali, S. F., Lin, P-J., Ko, H-S, Israel, N., Adikaram, D., Ahmed, Z., Albataineh, H., Aljawrneh, B., Allada, K., Allison, S., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Biswas, D., Brash, E., Bulumulla, D., Campbell, J., Camsonne, A., Carmignotto, M., Castellano, J., Chen, C., Chen, J-P., Chetry, T., Christy, M. E., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J. C., Dusa, S. Covrig, Crowe, B., Danagoulian, S., Danley, T., De Persio, F., Deconinck, W., Defurne, M., Desnault, C., Di, D., Duer, M., Duran, B., Ent, R., Fanelli, C., Franklin, G., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Glamazdin, O., Gnanvo, K., Gray, V. M., Gu, C., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holmstrom, T., Horn, T., Huang, Y., Huber, G. M., Hyde, C., Ibrahim, H., Jen, C-M., Jin, K., Jones, M., Kabir, A., Keppel, C., Khachatryan, V., King, P. M., Li, S., Li, W. B., Liu, J., Liu, H., Liyanage, A., Magee, J., Malace, S., Mammei, J., Markowitz, P., McClellan, E., Mazouz, M., Meddi, F., Meekins, D., Mesik, K., Michaels, R., Mkrtchyan, A., Montgomery, R., Camacho, C. Muñoz, Myers, L. S., Nadel-Turonski, P., Nazeer, S. J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obretch, O. F., Ou, L., Palatchi, C., Pandey, B., Park, S., Park, K., Peng, C., Pomatsalyuk, R., Pooser, E., Puckett, A. J. R., Punjabi, V., Quinn, B., Rahman, S., Reimer, P. E., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N. H., Schmookler, B., Shabestari, M. H., Shahinyan, A., Sirca, S., Smith, G. R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Su, T., Subedi, A., Sulkosky, V., Sun, A., Thorne, L., Tian, Y., Ton, N., Tortorici, F., Trotta, R., Urciuoli, G. M., Voutier, E., Waidyawansa, B., Wang, Y., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z., Yero, C., Zhang, J., Zhao, Y., and Zhu, P.
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Experiment, Nuclear Experiment
Abstract: We report high-precision measurements of the Deeply Virtual Compton Scattering (DVCS) cross section at high values of the Bjorken variable $x_B$. DVCS is sensitive to the Generalized Parton Distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton Form Factors (CFFs) of the nucleon as a function of $x_B$, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.
Published: 2022
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16. New Measurements of the Beam-Normal Single Spin Asymmetry in Elastic Electron Scattering Over a Range of Spin-0 Nuclei

Author: PREX, Collaborations, CREX, Adhikari, D., Albataineh, H., Androic, D., Aniol, K., Armstrong, D. S., Averett, T., Gayoso, C. Ayerbe, Barcus, S., 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., Hauenstein, F., Henry, W., Horowitz, C. J., Jantzi, C., Jian, S., Johnston, S., Jones, D. C., Karki, B., Kakkar, S., Katugampola, S., Keppel, C. E., King, P. M., King, D. E., Knauss, M., Kumar, K. S., Kutz, T., Lashley-Colthirst, N., Leverick, G., Liu, H., Liyange, N., Malace, S., Mammei, J., Mammei, R., McCaughan, M., McNulty, D., Meekins, D., Metts, C., Michaels, R., Mihovilovic, M., Mondal, M. M., Napolitano, J., Nikolaev, D., Rashad, M. N. H., Owen, V., Palatchi, C., Pan, J., Pandey, B., Park, S., Paschke, K. D., Petrusky, M., Pitt, M. L., Premathilake, S., Puckett, A. J. R., Quinn, B., Radloff, R., Rahman, S., Rathnayake, A., Reed, B. T., Reimer, P. E., Richards, R., Riordan, S., Roblin, Y., Seeds, S., Shahinyan, A., Souder, P. A., Tang, L., Thiel, M., Tian, Y., Urciuoli, G. M., Wertz, E. W., Wojtsekhowski, B., Xiong, W., Yale, B., Ye, T., Zec, A., Zhang, W., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: We report precision determinations of the beam normal single spin asymmetries ($A_n$) in the elastic scattering of 0.95 and 2.18~GeV electrons off $^{12}$C, $^{40}$Ca, $^{48}$Ca, and $^{208}$Pb at very forward angles where the most detailed theoretical calculations have been performed. The first measurements of $A_n$ for $^{40}$Ca and $^{48}$Ca are found to be similar to that of $^{12}$C, consistent with expectations thus demonstrating the validity of theoretical calculations for nuclei with Z~$\leq20$. We also report $A_n$ for $^{208}$Pb at two new momentum transfers (Q$^2$) extending the previous measurement. Our new data confirm the surprising result previously reported, with all three data points showing significant disagreement with the results from the $Z\leq 20$ nuclei. These data confirm our basic understanding of the underlying dynamics that govern $A_n$ for nuclei containing $\lesssim 50$ nucleons, but point to the need for further investigation to understand the unusual $A_n$ behaviour discovered for scattering off $^{208}$Pb., Comment: 7 pages, 2 figures
Published: 2021
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17. The cross-section measurement for the $^3{\textrm H}(e,e'K^+)nn\Lambda$ reaction

Author: Suzuki, K. N., Gogami, T., Pandey, B., Itabashi, K., Nagao, S., Okuyama, K., Nakamura, S. N., Tang, L., Abrams, D., Akiyama, T., Androic, D., Aniol, K., Gayoso, C. Ayerbe, Bane, J., Barcus, S., Barrow, J., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Camsonne, A., Castellanos, J., Chen, J-P., Chen, J., Covrig, S., Chrisman, D., Cruz-Torres, R., Das, R., Fuchey, E., Gnanvo, K., Garibaldi, F., Gautam, T., Gomez, J., Gueye, P., Hague, T. J., Hansen, O., Henry, W., Hauenstein, F., Higinbotham, D. W., Hyde, C. E., Kaneta, M., Keppel, C., Kutz, T., Lashley-Colthirst, N., Li, S., Liu, H., Mammei, J., Markowitz, P., McClellan, R. E., Meddi, F., Meekins, D., Michaels, R., Mihovilovič, M., Moyer, A., Nguyen, D., Nycz, M., Owen, V., Palatchi, C., Park, S., Petkovic, T., Premathilake, S., Reimer, P. E., Reinhold, J., Riordan, S., Rodriguez, V., Samanta, C., Santiesteban, S. N., Sawatzky, B., Širca, S., Slifer, K., Su, T., Tian, Y., Toyama, Y., Uehara, K., Urciuoli, G. M., Votaw, D., Williamson, J., Wojtsekhowski, B., Wood, S. A., Yale, B., Ye, Z., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: The small binding energy of the hypertrition leads to predictions of non-existence of bound hypernuclei for isotriplet three-body systems such as $nn\Lambda$. However, invariant mass spectroscopy at GSI has reported events that may be interpreted as the bound $nn\Lambda$ state. The $nn\Lambda$ state was sought by missing-mass spectroscopy via the $(e,e'K^+)$ reaction at Jefferson Lab's experimental Hall A. The present experiment has higher sensitivity to the $nn\Lambda$-state investigation in terms of better precision by a factor of about three. The analysis shown in this article focuses on the derivation of the reaction cross-section for the $^3{\rm{H}}(\gamma^{*},K^+)\textrm{X}$ reaction. Events that were detected in an acceptance, where a Monte Carlo simulation could reproduce the data well ($|\delta p/p| < 4\%$), were analyzed to minimize the systematic uncertainty. No significant structures were observed with the acceptance cuts, and the upper limits of the production cross-section of the $nn\Lambda$ state were obtained to be $21$ and $31~\rm{nb/sr}$ at the $90\%$ confidence level when theoretical predictions of $(-B_{\Lambda}, \Gamma) = (0.25,0.8)$ and $(0.55, 4.7)$ MeV, respectively, were assumed. The cross-section result provides valuable information for examining the existence of $nn\Lambda$., Comment: 27 pages, 12 figures
Published: 2021
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18. Deeply virtual Compton scattering off the neutron

Author: Benali, M., Desnault, C., Mazouz, M., Ahmed, Z., Albataineh, H., Allada, K., Aniol, K. A., Bellini, V., 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., Deur, A., Fassi, L. El, 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., Jimenez-Arguello, A. Marti, Meddi, F., Meekins, D., Michaels, R., Mihovilovic, M., Muangma, N., Camacho, C. Munoz, Nadel-Turonski, P., Nuruzzaman, N., Paremuzyan, R., Pomatsalyuk, R., Puckett, A., Punjabi, V., Qiang, Y., Rakhman, A., Rashad, M. N. H., Riordan, S., Roche, J., Russo, G., Sabatie, 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., and Zhu, P.
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Experiment, Nuclear Experiment
Abstract: The three-dimensional structure of nucleons (protons and neutrons) is embedded in so-called generalized parton distributions, which are accessible from deeply virtual Compton scattering. In this process, a high energy electron is scattered off a nucleon by exchanging a virtual photon. Then, a highly-energetic real photon is emitted from one of the quarks inside the nucleon, which carries information on the quark's transverse position and longitudinal momentum. By measuring the cross-section of deeply virtual Compton scattering, Compton form factors related to the generalized parton distributions can be extracted. Here, we report the observation of unpolarized deeply virtual Compton scattering off a deuterium target. From the measured photon-electroproduction cross-sections, we have extracted the cross-section of a quasi-free neutron and a coherent deuteron. Due to the approximate isospin symmetry of quantum chromodynamics, we can determine the contributions from the different quark flavours to the helicity-conserved Compton form factors by combining our measurements with previous ones probing the proton's internal structure. These results advance our understanding of the description of the nucleon structure, which is important to solve the proton spin puzzle.
Published: 2021
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19. Measurement of the Nucleon $F^n_2/F^p_2$ Structure Function Ratio by the Jefferson Lab MARATHON Tritium/Helium-3 Deep Inelastic Scattering Experiment

Author: MARATHON Collaboration, Abrams, D., Albataineh, H., Aljawrneh, B. S., Alsalmi, S., Aniol, K., Armstrong, W., Arrington, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Beck, A., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Blyth, D., Boeglin, W., Bulumulla, D., Butler, J., Camsonne, A., Carmignotto, M., Castellanos, J., Chen, J. -P., Cohen, E. O., Covrig, S., Craycraft, K., Cruz-Torres, R., Dongwi, B., Duran, B., Dutta, D., Fuchey, E., Gal, C., Gautam, T. N., Gilad, S., Gnanvo, K., Gogami, T., Gomez, J., Gu, C., Habarakada, A., Hague, T., Hansen, J. -O., Hattawy, M., Hauenstein, F., Higinbotham, D. W., Holt, R. J., Hughes, E. W., Hyde, C., Ibrahim, H., Jian, S., Joosten, S., Karki, A., Karki, B., Katramatou, A. T., Keith, C., Keppel, C., Khachatryan, M., Khachatryan, V., Khanal, A., Kievsky, A., King, D., King, P. M., Korover, I., Kulagin, S. A., Kumar, K. S., Kutz, T., Lashley-Colthirst, N., Li, S., Li, W., Liu, H., Liuti, S., Liyanage, N., Markowitz, P., McClellan, R. E., Meekins, D., Beck, S. Mey-Tal, Meziani, Z. -E., Michaels, R., Mihovilovic, M., Nelyubin, V., Nguyen, D., Nuruzzaman, Nycz, M., Obrecht, R., Olson, M., Owen, V. F., Pace, E., Pandey, B., Pandey, V., Paolone, M., Papadopoulou, A., Park, S., Paul, S., Petratos, G. G., Petti, R., Piasetzky, E., Pomatsalyuk, R., Premathilake, S., Puckett, A. J. R., Punjabi, V., Ransome, R. D., Rashad, M. N. H., Reimer, P. E., Riordan, S., Roche, J., Salme, G., Santiesteban, N., Sawatzky, B., Scopetta, S., Schmidt, A., Schmookler, B., Segal, J., Segarra, E. P., Shahinyan, A., Sirca, S., Sparveris, N., Su, T., Suleiman, R., Szumila-Vance, H., Tadepalli, A. S., Tang, L., Tireman, W., Tortorici, F., Urciuoli, G. M., Wojtsekhowski, B., Wood, S., Ye, Z. H., Ye, Z. Y., and Zhang, J.
Subjects: High Energy Physics - Experiment
Abstract: The ratio of the nucleon $F_2$ structure functions, $F_2^n/F_2^p$, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from $^3$H and $^3$He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab and used two high resolution spectrometers for electron detection, and a cryogenic target system which included a low-activity tritium cell. The data analysis used a novel technique exploiting the mirror symmetry of the two nuclei, which essentially eliminates many theoretical uncertainties in the extraction of the ratio. The results, which cover the Bjorken scaling variable range $0.19 < x < 0.83$, represent a significant improvement compared to previous SLAC and Jefferson Lab measurements for the ratio. They are compared to recent theoretical calculations and empirical determinations of the $F_2^n/F_2^p$ ratio.
Published: 2021

20. Form Factors and Two-Photon Exchange in High-Energy Elastic Electron-Proton Scattering

Author: Christy, M. E., Gautam, T., Ou, L., Schmookler, B., Wang, Y., Adikaram, D., Ahmed, Z., Albataineh, H., Ali, S. F., Aljawrneh, B., Allada, K., Allison, S. L., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Arrington, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Bhatt, H., Bhetuwal, D., Biswas, D., Brash, E., Bulumulla, D., Camacho, C. M., Campbell, J., Camsonne, A., Carmignotto, M., Castellanos, J., Chen, C., Chen, J-P., Chetry, T., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J. C., Dusa, S. Covrig, Crowe, B., Danagoulian, S., Danley, T., Deconinck, W., Defurne, M., Desnault, C., Di, D., Dlamini, M., Duer, M., Duran, B., Ent, R., Fanelli, C., Fuchey, E., Gal, C., Gaskell, D., Georges, F., Gilad, S., Glamazdin, O., Gnanvo, K., Gramolin, A. V., Gray, V. M., Gu, C., Habarakada, A., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Hernandez, A. V., Henry, W., Higinbotham, D. W., Holmstrom, T., Horn, T., Huang, Y., Huber, G. M., Hyde, C., Ibrahim, H., Israel, N., Jen, C-M., Jin, K., Jones, M., Kabir, A., Karki, B., Keppel, C., Khachatryan, V., King, P. M., Li, S., Li, W., Liu, H., Liu, J., Liyanage, A. H., Mack, D., Magee, J., Malace, S., Mammei, J., Markowitz, P., Mayilyan, S., McClellan, E., Meddi, F., Meekins, D., Mesick, K., Michaels, R., Mkrtchyan, A., Moffit, B., Montgomery, R., Myers, L. S., Nadel-Turonski, P., Nazeer, S. J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obrecht, R. F., Ohanyan, K., Palatchi, C., Pandey, B., Park, K., Park, S., Peng, C., Persio, F. D., Pomatsalyuk, R., Pooser, E., Puckett, A. J. R., Punjabi, V., Quinn, B., Rahman, S., Rashad, M. N. H., Riordan, S., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N. H., Shabestari, M. H., Shahinyan, A., Sirca, S., Smith, G. R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Stefanko, A., Su, T., Subedi, A., Sulkosky, V., Sun, A., Tan, Y., Thorne, L., Ton, N., Tortorici, F., Trotta, R., Uniyal, R., Urciuoli, G. M., Voutier, E., Waidyawansa, B., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z. H., Yero, C., Zhang, J., Zhao, Y. X., and Zhu, P.
Subjects: Nuclear Experiment, High Energy Physics - Experiment
Abstract: We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q$^2$) up to 15.75~\gevsq. Combined with existing data, these provide an improved extraction of the proton magnetic form factor at high Q$^2$ and double the range over which a longitudinal/transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q$^2$ and attributed to hard two-photon exchange (TPE) effects, extending to 8~(GeV/c)$^2$ the range of Q$^2$ for which a discrepancy is established at $>$95\% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q$^2$., Comment: 7 pages, 2 figures
Published: 2021
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21. Accurate Determination of the Neutron Skin Thickness of $^{208}$Pb through Parity-Violation in Electron Scattering

Author: Adhikari, D., Albataineh, H., Androic, D., Aniol, K., Armstrong, D. S., Averett, T., Barcus, S., Bellini, V., Beminiwattha, R. S., Benesch, J. F., Bhatt, H., Pathak, D. Bhatta, Bhetuwal, D., Blaikie, B., Campagna, Q., Camsonne, A., Cates, G. D., Chen, Y., Clarke, C., Cornejo, J. C., Dusa, S. Covrig, Datta, P., Deshpande, A., Dutta, D., Feldman, C., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Gayoso, C. Ayerbe, Gericke, M., Ghosh, C., Halilovic, I., Hansen, J. -O., Hauenstein, F., Henry, W., Horowitz, C. J., Jantzi, C., Jian, S., Johnston, S., Jones, D. C., Karki, B., Katugampola, S., Keppel, C., King, P. M., King, D. E., Knauss, M., Kumar, K. S., Kutz, T., Lashley-Colthirst, N., Leverick, G., Liu, H., Liyange, N., Malace, S., Mammei, R., Mammei, J., McCaughan, M., McNulty, D., Meekins, D., Metts, C., Michaels, R., Mondal, M. M., Napolitano, J., Narayan, A., Nikolaev, D., Rashad, M. N. H., Owen, V., Palatchi, C., Pan, 14 J., Pandey, B., Park, S., Paschke, K. D., Petrusky, M., Pitt, M. L., Premathilake, S., Puckett, A. J. R., Quinn, B., Radloff, R., Rahman, S., Rathnayake, A., Reed, B. T., Reimer, P. E., Richards, R., Riordan, S., Roblin, Y., Seeds, S., Shahinyan, A., Souder, P., Tang, L., Thiel, 16 M., Tian, Y., Urciuoli, G. M., Wertz, E. W., Wojtsekhowski, B., Yale, B., Ye, T., Yoon, A., Zec, A., Zhang, W., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: We report a precision measurement of the parity-violating asymmetry $A_{PV}$ in the elastic scattering of longitudinally polarized electrons from $^{208}$Pb. We measure $A_{PV}=550\pm 16 {\rm (stat)}\pm 8\ {\rm (syst)}$ parts per billion, leading to an extraction of the neutral weak form factor $F_W(Q^2 = 0.00616\ {\rm GeV}^2) = 0.368 \pm 0.013$. Combined with our previous measurement, the extracted neutron skin thickness is $R_n-R_p=0.283 \pm 0.071$~fm. The result also yields the first significant direct measurement of the interior weak density of $^{208}$Pb: $\rho^0_W = -0.0796\pm0.0036\ {\rm (exp.)}\pm0.0013\ {\rm (theo.)}\ {\rm fm}^{-3}$ leading to the interior baryon density $\rho^0_b = 0.1480\pm0.0036\ {\rm (exp.)}\pm0.0013\ {\rm (theo.)}\ {\rm fm}^{-3}$. The measurement accurately constrains the density dependence of the symmetry energy of nuclear matter near saturation density, with implications for the size and composition of neutron stars.
Published: 2021
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22. Measurement of the Ar(e,e$^\prime$ p) and Ti(e,e$^\prime$ p) cross sections in Jefferson Lab Hall A

Author: Gu, L., Abrams, D., Ankowski, A. M., Jiang, L., Aljawrneh, B., Alsalmi, S., Bane, J., Batz, A., Barcus, S., Barroso, M., Benhar, O., Bellini, V., Bericic, J., Biswas, D., Camsonne, A., Castellanos, J., Chen, J. -P., Christy, M. E., Craycraft, K., Cruz-Torres, R., Dai, H., Day, D., Dusa, S. -C., Fuchey, E., Gautam, T., Giusti, C., Gomez, J., Gu, C., Hague, T., Hansen, J. -O., Hauenstein, F., Higinbotham, D. W., Hyde, C., Keppel, C., Li, S., Lindgren, R., Liu, H., Mariani, C., McClellan, R. E., Meekins, D., Michaels, R., Mihovilovic, M., Murphy, M., Nguyen, D., Nycz, M., Ou, L., Pandey, B., Pandey, V., Park, K., Perera, G., Puckett, A. J. R., Santiesteban, S. N., Širca, S., Su, T., Tang, L., Tian, Y., Ton, N., Wojtsekhowski, B., Wood, S., Ye, Z., and Zhang, J.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: The E12-14-012 experiment, performed in Jefferson Lab Hall A, has collected exclusive electron-scattering data (e,e$^\prime$p) in parallel kinematics using natural argon and natural titanium targets. Here, we report the first results of the analysis of the data set corresponding to beam energy of 2,222 MeV, electron scattering angle 21.5 deg, and proton emission angle -50 deg. The differential cross sections, measured with $\sim$4% uncertainty, have been studied as a function of missing energy and missing momentum, and compared to the results of Monte Carlo simulations, obtained from a model based on the Distorted Wave Impulse Approximation., Comment: 14 pages, 8 figures (submitted to PRC)
Published: 2020
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23. Deep exclusive electroproduction of $\pi^0$ at high $Q^2$ in the quark valence regime

Author: The Jefferson Lab Hall A Collaboration, Dlamini, M., Karki, B., Ali, S. F., Lin, P-J., Georges, F., Ko, H-S, Israel, N., Rashad, M. N. H., Stefanko, A., Adikaram, D., Ahmed, Z., Albataineh, H., Aljawrneh, B., Allada, K., Allison, S., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Biswas, D., Brash, E., Bulumulla, D., Campbell, J., Camsonne, A., Carmignotto, M., Castellano, J., Chen, C., Chen, J-P., Chetry, T., Christy, M. E., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J. C., Dusa, S. Covrig, Crowe, B., Danagoulian, S., Danley, T., De Persio, F., Deconinck, W., Defurne, M., Desnault, C., Di, D., Duer, M., Duran, B., Ent, R., Fanelli, C., Franklin, G., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Glamazdin, O., Gnanvo, K., Gray, V. M., Gu, C., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holmstrom, T., Horn, T., Huang, Y., Huber, G. M., Hyde, C., Ibrahim, H., Jen, C-M., Jin, K., Jones, M., Kabir, A., Keppel, C., Khachatryan, V., King, P. M., Li, S., Li, W., Liu, J., Liu, H., Liyanage, A., Magee, J., Malace, S., Mammei, J., Markowitz, P., McClellan, E., Meddi, F., Meekins, D., Mesik, K., Michaels, R., Mkrtchyan, A., Montgomery, R., Camacho, C. Munoz, Myers, L. S., Nadel-Turonski, P., Nazeer, S. J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obretch, O. F., Ou, L., Palatchi, C., Pandey, B., Park, S., Park, K., Peng, C., Pomatsalyuk, R., Pooser, E., Puckett, A. J. R., Punjabi, V., Quinn, B., Rahman, S., Reimer, P. E., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N. H., Schmookler, B., Shabestari, M. H., Shahinyan, A., Sirca, S., Smith, G. R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Su, T., Subedi, A., Sulkosky, V., Sun, A., Thorne, L., Tian, Y., Ton, N., Tortorici, F., Trotta, R., Urciuoli, G. M., Voutier, E., Waidyawansa, B., Wang, Y., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z., Yero, C., Zhang, J., Zhao, Y., and Zhu, P.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of $x_B$ (0.36, 0.48 and 0.60) and $Q^2$ (3.1 to 8.4 GeV$^2$) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions $d\sigma_L/dt+\epsilon d\sigma_T/dt$, $d\sigma_{TT}/dt$, $d\sigma_{LT}/dt$ and $d\sigma_{LT'}/dt$ are extracted as a function of the proton momentum transfer $t-t_{min}$. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross-section throughout this kinematic range. The data are well described by calculations based on transversity Generalized Parton Distributions coupled to a helicity flip Distribution Amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.
Published: 2020
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24. 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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25. Backward-angle Exclusive pi0 Production above the Resonance Region

Author: Li, W. B., Huber, G. M., Stevens, J. R., Semenov-Tian-Shansky, K., Szymanowski, L., Pire, B., Amaryan, M., Androic, D., Aniol, K., Armstrong, D., Averett, T., Gayoso, C. Ayerbe, Boeglin, W., Boer, M., Camsonne, A., Chen, J., Dusa, S. Covrig, Deconinck, W., Defurne, M., Delcarro, F., Diefenthaler, M., Diehl, S., Elaasar, M., Fanelli, C., Fegan, S., Fuchey, E., Gaskell, D., Hansen, O., Hauenstein, F., Higinbotham, D., Blin, A. Hiller, Hurley, A., Hyde, C., Joo, K., Junaid, M., Kalantarians, N., Kay, S., Khachatryan, M., King, P., Kumar, V., Lersch, D., Lorenti, L., Markowitz, P., McCaughan, M., Mkrtchyan, A., Mkrtchyan, H., Niculescu, G., Niculescu, I., Papandreou, Z., Paremuzyan, R., Park, K., Paudyal, D., Roche, J., Rodas, A., Sawatzky, B., Schertz, A., Smith, G., Strakovsky, I., Tadevosyan, V., Usman, A., Voskanyan, H., and Yero, C.
Subjects: Nuclear Experiment
Abstract: The proposed measurement is a dedicated study of the exclusive electroproduction process,1H(e,e'p)pi0, in the backward-angle regime (u-channel process) above the resonance region. The produced pi0 is emitted 180 degrees opposite to the virtual-photon momentum. This study also aims to apply the well-known Rosenbluth separation technique that provides the model-independent differential cross-sections at the never explored u-channel kinematics region. Currently, the "soft-hard transition" in u-channel meson production remains an interesting and unexplored subject. The available theoretical frameworks offer competing interpretations for the observed backward-angle cross section peaks. In a "soft" hadronic Regge exchange description, the backward meson production comes from the interference between nucleon exchange and the meson produced via re-scattering within the nucleon. Whereas in the "hard" GPD-like backward collinear factorization regime, the scattering amplitude factorizes into a hard subprocess amplitude and baryon to meson transition distribution amplitudes (TDAs), otherwise known as super skewed parton distributions (SuperSPDs). Both TDAs and SPDs are universal non-perturbative objects of nucleon structure accessible only through backward-angle kinematics. The separated cross sections:sigma_T,sigma_L and T/L ratio at Q2=2-6 GeV2, provide a direct test of two predictions from the TDA model. The magnitude and u-dependence of the separated cross sections also provide a direct connection to the re-scattering Regge picture. The extracted interaction radius (from u-dependence) at different Q2 can be used to study the soft-hard transition in the u-channel kinematics. The acquisition of these data will be an important step forward in validating the existence of a backward factorization scheme of the nucleon structure function and establishing its applicable kinematic range.
Published: 2020

26. An experimental program with high duty-cycle polarized and unpolarized positron beams at Jefferson Lab

Author: Accardi, A., Afanasev, A., Albayrak, I., Ali, S. F., Amaryan, M., Annand, J. R. M., Arrington, J., Asaturyan, A., Atac, H., Avakian, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Barion, L., Battaglieri, M., Bellini, V., Beminiwattha, R., Benmokhtar, F., Berdnikov, V. V., Bernauer, J. C., Bertone, V., Bianconi, A., Biselli, A., Bisio, P., Blunden, P., Boer, M., Bondì, M., Brinkmann, K. -T., Briscoe, W. J., Burkert, V., Cao, T., Camsonne, A., Capobianco, R., Cardman, L., Carmignotto, M., Caudron, M., Causse, L., Celentano, A., Chatagnon, P., Chen, J. -P., Chetry, T., Ciullo, G., Cline, E., Cole, P. L., Contalbrigo, M., Costantini, G., D'Angelo, A., Darmé, L., Day, D., Defurne, M., De Napoli, M., Deur, A., De Vita, R., D'Hose, N., Diehl, S., Diefenthaler, M., Dongwi, B., Dupré, R., Dutrieux, H., Dutta, D., Ehrhart, M., Fassi, L. El, Elouadrhiri, L., Ent, R., Erler, J., Fernando, I. P., Filippi, A., Flay, D., Forest, T., Fuchey, E., Fucini, S., Furletova, Y., Gao, H., Gaskell, D., Gasparian, A., Gautam, T., Girod, F. -X., Gnanvo, K., Grames, J., Grauvoge, G. N., Gueye, P., Guidal, M., Habet, S., Hague, T. J., Hamilton, D. J., Hansen, O., Hasell, D., Hattawy, M., Higinbotham, D. W., Hobart, A., Horn, T., Hyde, C. E., Ibrahim, H., Ilyichev, A., Italiano, A., Joo, K., Joosten, S. J., Khachatryan, V., Kalantarians, N., Kalicy, G., Karky, B., Keller, D., Keppel, C., Kerver, M., Khandaker, M., Kim, A., Kim, J., King, P. M., Kinney, E., Klimenko, V., Ko, H. -S., Kohl, M., Kozhuharov, V., Kriesten, B. T., Krnjaic, G., Kubarovsky, V., Kutz, T., Lanza, L., Leali, M., Lenisa, P., Liyanage, N., Liu, Q., Liuti, S., Mammei, J., Mantry, S., Marchand, D., Markowitz, P., Marsicano, L., Mascagna, V., Mazouz, M., McCaughan, M., McKinnon, B., McNulty, D., Melnitchouk, W., Metz, A., Meziani, Z. -E., Migliorati, S., Mihovilovic, M., Milner, R., Mkrtchyan, A., Mkrtchyan, H., Movsisyan, A., Moutarde, H., Muhoza, M., Camacho, C. Muñoz, Murphy, J., Nadel-Turonski, P., Nardi, E., Nazeer, J., Niccolai, S., Niculescu, G., Novotny, R., Owens, J. F., Paolone, M., Pappalardo, L., Paremuzyan, R., Pasquini, B., Pasyuk, E., Patel, T., Pegg, I., Peng, C., Perera, D., Poelker, M., Price, K., Puckett, A. J. R., Raggi, M., Randazzo, N., Rashad, M. N. H., Rathnayake, M., Raue, B., Reimer, P. E., Rinaldi, M., Rizzo, A., Roblin, Y., Roche, J., Rondon-Aramayo, O., Sabatié, F., Salmè, G., Santopinto, E., Estrada, R. Santos, Sawatzky, B., Schmidt, A., Schweitzer, P., Scopetta, S., Sergeyeva, V., Shabestari, M., Shahinyan, A., Sharabian, Y., Širca, S., Smith, E. S., Sokhan, D., Somov, A., Sparveris, N., Spata, M., Spiesberger, H., Spreafico, M., Stepanyan, S., Stoler, P., Strakovsky, I., Suleiman, R., Suresh, M., Sznajder, P., Szumila-Vance, H., Tadevosyan, V., Tadepalli, A. S., Thomas, A. W., Tiefenback, M., Trotta, R., Ungaro, M., Valente, P., Vanderhaeghen, M., Venturelli, L., Voskanyan, H., Voutier, E., Wojtsekhowski, B., Wood, M. H., Wood, S., Xie, J., Xiong, W., Ye, Z., Yurov, M., Zaunick, H. -G., Zhamkochyan, S., Zhang, J., Zhang, S., Zhao, S., Zhao, Z. W., Zheng, X., Zhou, J., and Zorn, C.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental programs at the next generation of lepton accelerators. In the context of the hadronic physics program at Jefferson Lab (JLab), positron beams are complementary, even essential, tools for a precise understanding of the electromagnetic structure of nucleons and nuclei, in both the elastic and deep-inelastic regimes. For instance, elastic scattering of polarized and unpolarized electrons and positrons from the nucleon enables a model independent determination of its electromagnetic form factors. Also, the deeply-virtual scattering of polarized and unpolarized electrons and positrons allows unambiguous separation of the different contributions to the cross section of the lepto-production of photons and of lepton-pairs, enabling an accurate determination of the nucleons and nuclei generalized parton distributions, and providing an access to the gravitational form factors. Furthermore, positron beams offer the possibility of alternative tests of the Standard Model of particle physics through the search of a dark photon, the precise measurement of electroweak couplings, and the investigation of charged lepton flavor violation. This document discusses the perspectives of an experimental program with high duty-cycle positron beams at JLab., Comment: 18 pages, 7 figures This version superseeds the previous version which scientific content was decomposed into several more elaborated articles. All of these articles will be collected in the EPJ A Topical Issue about "Positron beam and physics at Jefferson Lab (e+@Jlab)"
Published: 2020
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27. Novel observation of isospin structure of short-range correlations in calcium isotopes

Author: Nguyen, D., Ye, Z., Aguilera, P., Ahmed, Z., Albataineh, H., Allada, K., Anderson, B., Anez, D., Aniol, K., Annand, J., Arrington, J., Averett, T., Baghdasaryan, H., Bai, X., Beck, A., Beck, S., Bellini, V., Benmokhtar, F., Camsonne, A., Chen, C., Chen, J. -P., Chirapatpimol, K., Cisbani, E., Dalton, M. M., Daniel, A., Day, D., Deconinck, W., Defurne, M., Flay, D., Fomin, N., Friend, M., Frullani, S., Fuchey, E., Garibaldi, F., Gaskell, D., Gilad, S., Gilman, R., Glamazdin, S., Gu, C., Guèye, P., Hanretty, C., Hansen, J. -O., Shabestari, M. Hashemi, Higinbotham, D. W., Huang, M., Iqbal, S., Jin, G., Kalantarians, N., Kang, H., her, A. Kelle, Korover, I., LeRose, J., Leckey, J., Li, S., Lindgren, R., Long, E., Mammei, J., Margaziotis, D. J., Markowitz, P., Meekins, D., Meziani, Z. -E., Michaels, R., Mihovilovi\v, M., Muangma, N., Camacho, C. Munoz, Norum, B. E., Nuruzzaman, Pan, K., Phillips, S., Piasetzky, E., Pomerantz, I., Posik, M., Punjabi, V., Qian, X., Qiang, Y., Qiu, X., Reimer, P. E., Rakhman, A., Riordan, S., Ron, G., Rondon-Aramayo, O., Saha, A., Selvy, L., Shahinyan, A., Shneor, R., \v, S., Slifer, K., Solvignon, P., Sparveris, N., Subedi, R., Sulkosky, V., Wang, D., Watson, J. W., Weinstein, L. B., Wojtsekhowski, B., Wood, S. A., Yaron, I., Zhan, X., Zhang, J., Zhang, Y. W., Zhao, B., Zheng, X., Zhu, P., and Zielinski, R.
Subjects: Nuclear Experiment
Abstract: Short Range Correlations (SRCs) have been identified as being responsible for the high momentum tail of the nucleon momentum distribution, n(k). Hard, short-range interactions of nucleon pairs generate the high momentum tail and imprint a universal character on n(k) for all nuclei at large momentum. Triple coincidence experiments have shown a strong dominance of np pairs, but these measurements involve large final state interactions. This paper presents the results from Jefferson Lab experiment E08014 which measured inclusive electron scattering cross-section from Ca isotopes. By comparing the inclusive cross section from 48Ca to 40Ca in a kinematic region dominated by SRCs we provide a new way to study the isospin structure of SRCs., Comment: 7 pages, 3 figures
Published: 2020
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28. Probing few-body nuclear dynamics via 3H and 3He (e,e'p)pn cross-section measurements

Author: Cruz-Torres, R., Nguyen, D., Hauenstein, F., Schmidt, A., Li, S., Abrams, D., Albataineh, H., Alsalmi, S., Androic, D., Aniol, K., Armstrong, W., Arrington, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Beck, A., Bellini, V., Benmokhtar, F., Bhatt, H., Bhetuwal, D., Biswas, D., Blyth, D., Boeglin, W., Bulumulla, D., Camsonne, A., Castellanos, J., Chen, J-P., Cohen, E. O., Covrig, S., Craycraft, K., Dongwi, B., Duer, M., Duran, B., Dutta, D., Fuchey, E., Gal, C., Gautam, T. N., Gilad, S., Gnanvo, K., Gogami, T., Golak, J., Gomez, J., Gu, C., Hague, A. Habarakada T., Hansen, O., Hattawy, M., Hen, O., Higinbotham, D. W., Hughes, E., Hyde, C., Ibrahim, H., Jian, S., Joosten, S., Kamada, H., Karki, A., Karki, B., Katramatou, A. T., Keppel, C., Khachatryan, M., Khachatryan, V., Khanal, A., King, D., King, P., Korover, I., Kutz, T., Lashley-Colthirst, N., Laskaris, G., Li, W., Liu, H., Liyanage, N., Markowitz, P., McClellan, R. E., Meekins, D., Meziani, S. Mey-Tal Beck Z-E., Michaels, R., Mihovilovic, M., Nelyubin, V., Nuruzzaman, N., Nycz, M., Obrecht, R., Olson, M., Ou, L., Owen, V., Pandey, B., Pandey, V., Papadopoulou, A., Park, S., Patsyuk, M., Paul, S., Petratos, G. G., Piasetzky, E., Pomatsalyuk, R., Premathilake, S., Puckett, A. J. R., Punjabi, V., Ransome, R., Rashad, M. N. H., Reimer, P. E., Riordan, S., Roche, J., Sargsian, M., Santiesteban, N., Sawatzky, B., Segarra, E. P., Schmookler, B., Shahinyan, A., Sirca, S., Skibinski, R., Sparveris, N., Su, T., Suleiman, R., Szumila-Vance, H., Tadepalli, A. S., Tang, L., Tireman, W., Topolnicki, K., Tortorici, F., Urciuoli, G., Weinstein, L. B., Witala, H., Wojtsekhowski, B., Wood, S., Ye, Z. H., Ye, Z. Y., and Zhang, J.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: We report the first measurement of the \eep three-body breakup reaction cross sections in helium-3 ($^3$He) and tritium ($^3$H) at large momentum transfer ($\langle Q^2 \rangle \approx 1.9$ (GeV/c)$^2$) and $x_B>1$ kinematics, where the cross section should be sensitive to quasielastic (QE) scattering from single nucleons. The data cover missing momenta $40 \le p_{miss} \le 500$ MeV/c that, in the QE limit with no rescattering, equals the initial momentum of the probed nucleon. The measured cross sections are compared with state-of-the-art ab-initio calculations. Overall good agreement, within $\pm20\%$, is observed between data and calculations for the full $p_{miss}$ range for $^3$H and for $100 \le p_{miss} \le 350$ MeV/c for $^3$He. Including the effects of rescattering of the outgoing nucleon improves agreement with the data at $p_{miss} > 250$ MeV/c and suggests contributions from charge-exchange (SCX) rescattering. The isoscalar sum of $^3$He plus $^3$H, which is largely insensitive to SCX, is described by calculations to within the accuracy of the data over the entire $p_{miss}$ range. This validates current models of the ground state of the three-nucleon system up to very high initial nucleon momenta of $500$ MeV/c., Comment: Accepted for publication in PRL. 8 pages, 3 figures, and online supplementary materials
Published: 2020
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29. Measurement of the cross sections for inclusive electron scattering in the E12-14-012 experiment at Jefferson Lab

Author: Murphy, M., Dai, H., Gu, L., Abrams, D., Ankowski, A. M., Aljawrneh, B., Alsalmi, S., Bane, J., Barcus, S., Benhar, O., Bellini, V., Bericic, J., Biswas, D., Camsonne, A., Castellanos, J., Chen, J. -P., Christy, M. E., Craycraft, K., Cruz-Torres, R., Day, D., Dusa, S. -C., Fuchey, E., Gautam, T., Giusti, C., Gomez, J., Gu, C., Hague, T., Hansen, J. -O., Hauenstein, F., Higinbotham, D. W., Hyde, C., Jen, C. M., Keppel, C., Li, S., Lindgren, R., Liu, H., Mariani, C., McClellan, R. E., Meekins, D., Michaels, R., Mihovilovic, M., Nguyen, D., Nycz, M., Ou, L., Pandey, B., Pandey, V., Park, K., Perera, G., Puckett, A. J. R., Santiesteban, S. N., Širca, S., Su, T., Tang, L., Tian, Y., Ton, N., Wojtsekhowski, B., Wood, S., Ye, Z., and Zhang, J.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Experiment
Abstract: The E12-14-012 experiment performed at Jefferson Lab Hall A has collected inclusive electron-scattering data for different targets at the kinematics corresponding to beam energy 2.222 GeV and scattering angle 15.54 deg. Here we present a comprehensive analysis of the collected data and compare the double-differential cross sections for inclusive scattering of electrons, extracted using solid targets (aluminum, carbon, and titanium) and a closed argon-gas cell. The data extend over broad range of energy transfer, where quasielastic interaction, Delta-resonance excitation, and inelastic scattering yield contributions to the cross section. The double-differential cross sections are reported with high precision (~3%) for all targets over the covered kinematic range., Comment: 11 pages, 10 figures
Published: 2019
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30. Probing for high momentum protons in $^4$He via the $^4He(e,e'p)X$ reaction

Author: Iqbal, S., Benmokhtar, F., Ivanov, M., See, N., Aniol, K., Higinbotham, D. W., Boyd, C., Gadsby, A., Gilad, S., Saha, A., Udias, J. M., Goodwill, J. S., Finton, D., Boyer, A., Ye, Z., Solvignon, P., Aguilera, P., Ahmed, Z., Albataineh, H., Allada, K., Anderson, B., Anez, D., Annand, J., Arrington, J., Averett, T., Baghdasaryan, H., Bai, X., Beck, A., Beck, S., Bellini, V., Camsonne, A., Chen, C., Chen, J. -P., Chirapatpimol, K., Cisbani, E., Dalton, M. M., Daniel, A., Day, D., Deconinck, W., Defurne, M., Flay, D., Fomin, N., Friend, M., Frullani, S., Fuchey, E., Garibaldi, F., Gaskell, D., Gilman, R., Glamazdin, S., Gu, C., Gueye, P., Hanretty, C., Hansen, J. -O., Shabestari, M. Hashemi, Huang, M., Jin, G., Kalantarians, N., Kang, H., Kelleher, A., Korover, I., LeRose, J., Leckey, J., Lindgren, R., Long, E., Mammei, J., Margaziotis, D. J., Markowitz, P., Meekins, D., Meziani, Z., Michaels, R., Mihovilovic, M., Muangma, N., Camacho, C. Munoz, Norum, B., Nuruzzaman, Nuruzzaman, Pan, K., Phillips, S., Piasetzky, E., Pomerantz, I., Posik, M., Punjabi, V., Qian, X., Qiang, Y., Qiu, X., Reimer, P. E., Rakhman, A ., Riordan, S., Ron, G., Rondon-Aramayo, O., Selvy, L., Shahinyan, A., Shneor, R., Sirca, S., Slifer, K., Sparveris, N., Subedi, R., Sulkosky, V., Wang, D., Watson, J. W., Weinstein, L. B., Wojtsekhowski, B., Wood, S. A., Yaron, I., Zhan, X., Zhang, J., Zhang, Y. W., Zhao, B., Zheng, X., Zhu, P., and Zielinski, R.
Subjects: Nuclear Experiment
Abstract: Experimental cross sections for the $^4He(e,e'p)X$ reaction up to a missing momentum of 0.632 GeV/$c$ at $x_B=1.24$ and $Q^2$=2(GeV/$c$)$^2$ are reported. The data are compared to Relativistic Distorted Wave Impulse Approximation(RDWIA) calculations for $^4He(e,e'p)^3H$ channel. Significantly more events in the triton mass region are measured for $p_{m}$$>$0.45 GeV/$c$ than are predicted by the theoretical model, suggesting that the effects of initial-state multi-nucleon correlations are stronger than expected by the RDWIA model., Comment: Submitted to PRC
Published: 2019

31. Measurement of the cross section for hard exclusive $\pi^0$ leptoproduction

Author: Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Buechele, M., Burtsev, V. E., Chang, W. -C., Chatterjee, C., Chiosso, M., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dusaev, R. R., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Perdekamp, M. Grosse, Grube, B., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Iwata, T., Jandek, M., Jary, T., Joosten, R., Joerg, P., Juraskova, K., Kabuss, E., Kaspar, F., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kveton, A., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Lin, P. -J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Moretti, A., Naim, C., Nagaytsev, A., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevskiy, A. G., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Peskova, M., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sbrizzai, G., Schmieden, H., Selyunin, A., Silva, L., Sinha, L., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veit, B. M., Veloso, J., Vidon, A., Virius, M., Wagner, M., Wallner, S., Wilfert, M., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhao, Y., and Ziembicki, M.
Subjects: High Energy Physics - Experiment
Abstract: We report on a measurement of hard exclusive $\pi^0$ muoproduction on the proton by COMPASS using 160 GeV/$c$ polarised $\mu^+$ and $\mu^-$ beams of the CERN SPS impinging on a liquid hydrogen target. From the average of the measured $\mu^+$ and $\mu^-$ cross sections, the virtual-photon proton cross section is determined as a function of the squared four-momentum transfer between initial and final proton in the range $0.08\,(\text{GeV/}c)^2 < |t| < 0.64\,(\text{GeV/}c)^2$. The average kinematics of the measurement are $\langle Q^2 \rangle =2.0\; {(\text{GeV}/c)^2}$, $\langle \nu \rangle = 12.8\; {\text{GeV}}$, $\langle x_{Bj} \rangle = 0.093 $ and $\langle -t \rangle = 0.256\; {(\text{GeV}/c)^2} $. Fitting the azimuthal dependence reveals a combined contribution by transversely and longitudinally polarised photons of $(8.1 \ \pm \ 0.9_{\text{stat}}{}_{- \ 1.0}^{+ \ 1.1}\big\rvert_{\text{sys}})\,{\text{nb}}/{(\text{GeV}/c)^{2}}$, as well as transverse-transverse and longitudinal-transverse interference contributions of $(-6.0 \pm 1.3_{\text{stat}}{}_{- \ 0.7}^{+ \ 0.7}\big\rvert_{\text{sys}})\,{\text{nb}}/{(\text{GeV}/c)^{2}}$ and $(1.4 \pm 0.5_{\text{stat}}{}_{- \ 0.2}^{+ \ 0.3}\big\rvert_{\text{sys}})\,{\text{nb}}/{(\text{GeV}/c)^{2}}$, respectively. Our results provide important input for modelling Generalised Parton Distributions. In the context of the phenomenological Goloskokov-Kroll model, the statistically significant transverse-transverse interference contribution constitutes clear experimental evidence for the chiral-odd GPD $\overline{E}_T$., Comment: 9 pages, 5 figures
Published: 2019
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32. Comparing proton momentum distributions in $A=2$ and 3 nuclei via $^2$H $^3$H and $^3$He $(e, e'p)$ measurements

Author: Cruz-Torres, R., Li, S., Hauenstein, F., Schmidt, A., Nguyen, D., Abrams, D., Albataineh, H., Alsalmi, S., Androic, D., Aniol, K., Armstrong, W., Arrington, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Beck, A., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Blyth, D., Boeglin, W., Bulumulla, D., Camsonne, A., Castellanos, J., Chen, J. -P., Cohen, E. O., Covrig, S., Craycraft, K., Dongwi, B., Duer, M., Duran, B., Dutta, D., Fuchey, E., Gal, C., Gautam, T. N., Gilad, S., Gnanvo, K., Gogami, T., Gomez, J., Gu, C., Habarakada, A., Hague, T., Hansen, O., Hattawy, M., Hen, O., Higinbotham, D. W., Hughes, E., Hyde, C., Ibrahim, H., Jian, S., Joosten, S., Karki, A., Karki, B., Katramatou, A. T., Keppel, C., Khachatryan, M., Khachatryan, V., Khanal, A., King, D., King, P., Korover, I., Kutz, T., Lashley-Colthirst, N., Laskaris, G., Li, W., Liu, H., Liyanage, N., Lonardoni, D., Machleidt, R., Marcucci, L. E., Markowitz, P., McClellan, R. E., Meekins, D., Beck, S. Mey-Tal, Meziani, Z. -E., Michaels, R., Mihovilovic, M., Nelyubin, V., Nuruzzaman, N., Nycz, M., Obrecht, R., Olson, M., Ou, L., Owen, V., Pandey, B., Pandey, V., Papadopoulou, A., Park, S., Patsyuk, M., Paul, S., Petratos, G. G., Piasetzky, E., Pomatsalyuk, R., Premathilake, S., Puckett, A. J. R., Punjabi, V., Ransome, R., Rashad, M. N. H., Reimer, P. E., Riordan, S., Roche, J., Sammarruca, F., Santiesteban, N., Sawatzky, B., Segarra, E. P., Schmookler, B., Shahinyan, A., Širch, S., Sparveris, N., Su, T., Suleiman, R., Szumila-Vance, H., Tadepalli, A. S., Tang, L., Tireman, W., Tortorici, F., Urciuoli, G., Viviani, M., Weinstein, L. B., Wojtsekhowski, B., Wood, S., Ye, Z. H., Ye, Z. Y., and Zhang, J.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: We report the first measurement of the $(e,e'p)$ reaction cross-section ratios for Helium-3 ($^3$He), Tritium ($^3$H), and Deuterium ($d$). The measurement covered a missing momentum range of $40 \le p_{miss} \le 550$ MeV$/c$, at large momentum transfer ($\langle Q^2 \rangle \approx 1.9$ (GeV$/c$)$^2$) and $x_B>1$, which minimized contributions from non quasi-elastic (QE) reaction mechanisms. The data is compared with plane-wave impulse approximation (PWIA) calculations using realistic spectral functions and momentum distributions. The measured and PWIA-calculated cross-section ratios for $^3$He$/d$ and $^3$H$/d$ extend to just above the typical nucleon Fermi-momentum ($k_F \approx 250$ MeV$/c$) and differ from each other by $\sim 20\%$, while for $^3$He/$^3$H they agree within the measurement accuracy of about 3\%. At momenta above $k_F$, the measured $^3$He/$^3$H ratios differ from the calculation by $20\% - 50\%$. Final state interaction (FSI) calculations using the generalized Eikonal Approximation indicate that FSI should change the $^3$He/$^3$H cross-section ratio for this measurement by less than 5\%. If these calculations are correct, then the differences at large missing momenta between the $^3$He/$^3$H experimental and calculated ratios could be due to the underlying $NN$ interaction, and thus could provide new constraints on the previously loosely-constrained short-distance parts of the $NN$ interaction., Comment: 8 pages, 3 figures (4 panels)
Published: 2019
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33. First Measurement of the Ar$(e,e^\prime)X$ Cross Section at Jefferson Lab

Author: Dai, H., Murphy, M., Pandey, V., Abrams, D., Nguyen, D., Aljawrneh, B., Alsalmi, S., Ankowski, A. M., Bane, J., Barcus, S., Benhar, O., Bellini, V., Bericic, J., Biswas, D., Camsonne, A., Castellanos, J., Chen, J. -P., Christy, M. E., Craycraft, K., Cruz-Torres, R., Day, D., Dusa, S. -C., Fuchey, E., Gautam, T., Giusti, C., Gomez, J., Gu, C., Hague, T., Hansen, J. -O., Hauenstein, F., Higinbotham, D. W., Hyde, C., Jen, C. M., Keppel, C., Li, S., Lindgren, R., Liu, H., Mariani, C., McClellan, R. E., Meekins, D., Michaels, R., Mihovilovic, M., Nycz, M., Ou, L., Pandey, B., Park, K., Perera, G., Puckett, A. J. R., Santiesteban, S. N., Širca, S., Su, T., Tang, L., Tian, Y., Ton, N., Wojtsekhowski, B., Wood, S., Ye, Z., and Zhang, J.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: The success of the ambitious programs of both long- and short-baseline neutrino-oscillation experiments employing liquid-argon time-projection chambers will greatly rely on the precision with which the weak response of the argon nucleus can be estimated. In the E12-14-012 experiment at Jefferson Lab Hall A, we have studied the properties of the argon nucleus by scattering a high-quality electron beam off a high-pressure gaseous argon target. Here, we present the measured $^{40}$Ar$(e,e^{\prime})$ double differential cross section at incident electron energy $E=2.222$~GeV and scattering angle $\theta = 15.541^\circ$. The data cover a broad range of energy transfers, where quasielastic scattering and delta production are the dominant reaction mechanisms. The result for argon is compared to our previously reported cross sections for titanium and carbon, obtained in the same kinematical setup., Comment: 6 pages, 4 figures
Published: 2018
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34. First Measurement of the Ti$(e,e^\prime){\rm X}$ Cross Section at Jefferson Lab

Author: Dai, H., Murphy, M., Pandey, V., Abrams, D., Nguyen, D., Aljawrneh, B., Alsalmi, S., Ankowski, A. M., Bane, J., Barcus, S., Benhar, O., Bellini, V., Bericic, J., Biswas, D., Camsonne, A., Castellanos, J., Chen, J. -P., Christy, M. E., Craycraft, K., Cruz-Torres, R., Day, D., Dusa, S. -C., Fuchey, E., Gautam, T., Giusti, C., Gomez, J., Gu, C., Hague, T., Hansen, J. -O., Hauenstein, F., Higinbotham, D. W., Hyde, C., Jen, C. M., Keppel, C., Li, S., Lindgren, R., Liu, H., Mariani, C., McClellan, R. E., Meekins, D., Michaels, R., Mihovilovic, M., Nycz, M., Ou, L., Pandey, B., Park, K., Perera, G., Puckett, A. J. R., Širca, S., Su, T., Tang, L., Tian, Y., Ton, N., Wojtsekhowski, B., Wood, S., Ye, Z., and Zhang, J.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, Nuclear Theory
Abstract: To probe CP violation in the leptonic sector using GeV energy neutrino beams in current and future experiments using argon detectors, precise models of the complex underlying neutrino and antineutrino interactions are needed. The E12-14-012 experiment at Jefferson Lab Hall A was designed to perform a combined analysis of inclusive and exclusive electron scatterings on both argon ($N = 22$) and titanium ($Z = 22$) nuclei using GeV energy electron beams. The measurement on titanium nucleus provides essential information to understand the neutrino scattering on argon, large contribution to which comes from scattering off neutrons. Here we report the first experimental study of electron-titanium scattering as double differential cross section at beam energy $E=2.222$ GeV and electron scattering angle $\theta = 15.541$ deg, measured over a broad range of energy transfer, spanning the kinematical regions in which quasielastic scattering and delta production are the dominant reaction mechanisms. The data provide valuable new information needed to develop accurate theoretical models of the electromagnetic and weak cross sections of these complex nuclei in the kinematic regime of interest to neutrino experiments., Comment: 6 pages, 5 figures. Version published in Physical Review C
Published: 2018
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35. Light isovector resonances in $\pi^- p \to \pi^-\pi^-\pi^+ p$ at 190 GeV/${\it c}$

Author: Aghasyan, M., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Buechele, M., Burtsev, V. E., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dusaev, R. R., Dziewiecki, M., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Hass, F., Hahne, D., Hamar, G., von Harrach, D., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Juraskova, K., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kuznetsov, I. I., Kveton, A., Lednev, A. A., Levchenko, E. A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Moretti, A., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peskova, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schluter, T., Schmeing, S., Schmieden, H., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veit, B. M., Veloso, J., Vidon, A., Virius, M., Wallner, S., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., and Ziembicki, M.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: We have performed the most comprehensive resonance-model fit of $\pi^-\pi^-\pi^+$ states using the results of our previously published partial-wave analysis (PWA) of a large data set of diffractive-dissociation events from the reaction $\pi^- + p \to \pi^-\pi^-\pi^+ + p_\text{recoil}$ with a 190 GeV/$c$ pion beam. The PWA results, which were obtained in 100 bins of three-pion mass, $0.5 < m_{3\pi} < 2.5$ GeV/$c^2$, and simultaneously in 11 bins of the reduced four-momentum transfer squared, $0.1 < t' < 1.0$ $($GeV$/c)^2$, are subjected to a resonance-model fit using Breit-Wigner amplitudes to simultaneously describe a subset of 14 selected waves using 11 isovector light-meson states with $J^{PC} = 0^{-+}$, $1^{++}$, $2^{++}$, $2^{-+}$, $4^{++}$, and spin-exotic $1^{-+}$ quantum numbers. The model contains the well-known resonances $\pi(1800)$, $a_1(1260)$, $a_2(1320)$, $\pi_2(1670)$, $\pi_2(1880)$, and $a_4(2040)$. In addition, it includes the disputed $\pi_1(1600)$, the excited states $a_1(1640)$, $a_2(1700)$, and $\pi_2(2005)$, as well as the resonancelike $a_1(1420)$. We measure the resonance parameters mass and width of these objects by combining the information from the PWA results obtained in the 11 $t'$ bins. We extract the relative branching fractions of the $\rho(770) \pi$ and $f_2(1270) \pi$ decays of $a_2(1320)$ and $a_4(2040)$, where the former one is measured for the first time. In a novel approach, we extract the $t'$ dependence of the intensity of the resonances and of their phases. The $t'$ dependence of the intensities of most resonances differs distinctly from the $t'$ dependence of the nonresonant components. For the first time, we determine the $t'$ dependence of the phases of the production amplitudes and confirm that the production mechanism of the Pomeron exchange is common to all resonances., Comment: 224 pages, 172 figures
Published: 2018
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36. Transverse Extension of Partons in the Proton probed by Deeply Virtual Compton Scattering

Author: Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Buechele, M., Burtin, E., Burtsev, V. E., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dusaev, R. R., Dziewiecki, M., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Juraskova, K., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kuznetsov, I. I., Kveton, A., Lednev, A. A., Levchenko, E. A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marchand, C., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Moretti, A., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesaro, G., Pesek, M., Peskova, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmieden, H., Schoennig, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veit, B. M., Veloso, J., Vidon, A., Virius, M., Wallner, S., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: We report on the first measurement of exclusive single-photon muoproduction on the proton by COMPASS using 160 GeV/$c$ polarized $\mu^+$ and $\mu^-$ beams of the CERN SPS impinging on a liquid hydrogen target. We determine the dependence of the average of the measured $\mu^+$ and $\mu^-$ cross sections for deeply virtual Compton scattering on the squared four-momentum transfer $t$ from the initial to the final final proton. The slope $B$ of the $t$-dependence is fitted with a single exponential function, which yields $B=(4.3 \ \pm \ 0.6_{\text{stat}}\_{- \ 0.3}^{+ \ 0.1}\big\rvert_{\text{sys}}) (\text{GeV}/c)^{-2}$. This result can be converted into an average transverse extension of partons in the proton, $\sqrt{\langle r_{\perp}^2 \rangle} = (0.58 \ \pm \ 0.04_{\text{stat}}\_{- \ 0.02}^{+ \ 0.01}\big\rvert_{\text{sys}})\text{fm}$. For this measurement, the average virtuality of the photon mediating the interaction is $\langle Q^2 \rangle = 1.8\,(\text{GeV/}c)^2$ and the average value of the Bjorken variable is $\langle x_{\text{Bj}} \rangle = 0.056$., Comment: 13 pages, 5 figures
Published: 2018
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37. Search for three-nucleon short-range correlations in light nuclei

Author: Ye, Z., Solvignon, P., Nguyen, D., Aguilera, P., Ahmed, Z., Albataineh, H., Allada, K., Anderson, B., Anez, D., Aniol, K., Annand, J., Arrington, J., Averett, T., Baghdasaryan, H., Bai, X., Beck, A., Beck, S., Bellini, V., Benmokhtar, F., Camsonne, A., Chen, C., Chen, J. -P., Chirapatpimol, K., Cisbani, E., Dalton, M. M., Daniel, A., Day, D., Deconinck, W., Defurne, M., Flay, D., Fomin, N., Friend, M., Frullani, S., Fuchey, E., Garibaldi, F., Gaskell, D., Gilad, S., Gilman, R., Glamazdin, S., Gu, C., Gueye, P., Hanretty, C., Hansen, J. -O., Shabestari, M. Hashemi, Higinbotham, D. W., Huang, M., Iqbal, S., Jin, G., Kalantarians, N., Kang, H., Kelleher, A., Korover, I., LeRose, J., Leckey, J., Lindgren, R., Long, E., Mammei, J., Margaziotis, D. J., Markowitz, P., Meekins, D., Meziani, Z., Michaels, R., Mihovilovic, M., Muangma, N., Camacho, C. Munoz, Norum, B., Nuruzzaman, Pan, K., Phillips, S., Piasetzky, E., Pomerantz, I., Posik, M., Punjabi, V., Qian, X., Qiang, Y., Qiu, X., Reimer, P. E., Rakhman, A., Riordan, S., Ron, G., Rondon-Aramayo, O., Saha, A., Selvy, L., Shahinyan, A., Shneor, R., Sirca, S., Slifer, K., Sparveris, N., Subedi, R., Sulkosky, V., Wang, D., Watson, J. W., Weinstein, L. B., Wojtsekhowski, B., Wood, S. A., Yaron, I., Zhan, X., Zhang, J., Zhang, Y. W., Zhao, B., Zheng, X., Zhu, P., and Zielinski, R.
Subjects: Nuclear Experiment
Abstract: We present new data probing short-range correlations (SRCs) in nuclei through the measurement of electron scattering off high-momentum nucleons in nuclei. The inclusive 4He/3He cross section ratio is observed to be both x and Q2 independent for 1.5 < x < 2, confirming the dominance of two- nucleon (2N) short-range correlations (SRCs). For x > 2, our data do not support a previous claim of three-nucleon (3N) correlation dominance. While contributions beyond those from stationary 2N- SRCs are observed, our data show that isolating 3N-SRCs is more complicated than for 2N-SRCs., Comment: 6 pages, 2 figures, new experimental results from JLab E08-014
Published: 2017
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38. Longitudinal double-spin asymmetry $A_1^{\rm p}$ and spin-dependent structure function $g_1^{\rm p}$ of the proton at small values of $x$ and $Q^2$

Author: Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Buechele, M., Burtsev, V. E., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dusaev, R. R., Dziewiecki, M., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kuznetsov, I. I., Kveton, A., Lednev, A. A., Levchenko, E. A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Moretti, A., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peskova, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veloso, J., Vidon, A., Virius, M., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment
Abstract: We present a precise measurement of the proton longitudinal double-spin asymmetry $A_1^{\rm p}$ and the proton spin-dependent structure function $g_1^{\rm p}$ at photon virtualities $0.006~({\rm GeV}/c)^2
Published: 2017
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39. Transverse-momentum-dependent Multiplicities of Charged Hadrons in Muon-Deuteron Deep Inelastic Scattering

Author: Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Buechele, M., Burtsev, V. E., Capozza, L., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dusaev, R. R., Dziewiecki, M., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kuznetsov, I. I., Kveton, A., Lednev, A. A., Levchenko, E. A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Moretti, A., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peskova, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veloso, J., Vidon, A., Virius, M., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: A semi-inclusive measurement of charged hadron multiplicities in deep inelastic muon scattering off an isoscalar target was performed using data collected by the COMPASS Collaboration at CERN. The following kinematic domain is covered by the data: photon virtuality $Q^{2}>1$ (GeV/$c$)$^2$, invariant mass of the hadronic system $W > 5$ GeV/$c^2$, Bjorken scaling variable in the range $0.003 < x < 0.4$, fraction of the virtual photon energy carried by the hadron in the range $0.2 < z < 0.8$, square of the hadron transverse momentum with respect to the virtual photon direction in the range 0.02 (GeV/$c)^2 < P_{\rm{hT}}^{2} < 3$ (GeV/$c$)$^2$. The multiplicities are presented as a function of $P_{\rm{hT}}^{2}$ in three-dimensional bins of $x$, $Q^2$, $z$ and compared to previous semi-inclusive measurements. We explore the small-$P_{\rm{hT}}^{2}$ region, i.e. $P_{\rm{hT}}^{2} < 1$ (GeV/$c$)$^2$, where hadron transverse momenta are expected to arise from non-perturbative effects, and also the domain of larger $P_{\rm{hT}}^{2}$, where contributions from higher-order perturbative QCD are expected to dominate. The multiplicities are fitted using a single-exponential function at small $P_{\rm{hT}}^{2}$ to study the dependence of the average transverse momentum $\langle P_{\rm{hT}}^{2}\rangle$ on $x$, $Q^2$ and $z$. The power-law behaviour of the multiplicities at large $P_{\rm{hT}}^{2}$ is investigated using various functional forms. The fits describe the data reasonably well over the full measured range., Comment: 28 pages, 20 figures
Published: 2017
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40. New analysis of $\eta\pi$ tensor resonances measured at the COMPASS experiment

Author: Jackura, A., Fernandez-Ramirez, C., Mikhasenko, M., Pilloni, A., Mathieu, V., Nys, J., Pauk, V., Szczepaniak, A. P., Fox, G., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Buechele, M., Burtsev, V. E., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dusaev, R. R., Dziewiecki, M., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kuznetsov, I. I., Kveton, A., Lednev, A. A., Levchenko, E. A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peskova, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schluter, T., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veloso, J., Vidon, A., Virius, M., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Experiment
Abstract: We present a new amplitude analysis of the $\eta\pi$ $D$-wave in $\pi^- p\to \eta\pi^- p$ measured by COMPASS. Employing an analytical model based on the principles of the relativistic $S$-matrix, we find two resonances that can be identified with the $a_2(1320)$ and the excited $a_2^\prime(1700)$, and perform a comprehensive analysis of their pole positions. For the mass and width of the $a_2$ we find $M=(1307 \pm 1 \pm 6)$~MeV and $\Gamma=(112 \pm 1 \pm 8)$~MeV, and for the excited state $a_2^\prime$ we obtain $M=(1720 \pm 10 \pm 60)$~MeV and $\Gamma=(280\pm 10 \pm 70)$~MeV, respectively., Comment: 15 pages, 6 figures
Published: 2017
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41. Search for muoproduction of $X(3872)$ at COMPASS and indication of a new state $\widetilde{X}(3872)$

Author: Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Buechele, M., Burtsev, V. E., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dusaev, R. R., Dziewiecki, M., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kuznetsov, I. I., Kveton, A., Lednev, A. A., Levchenko, E. A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peskova, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veloso, J., Vidon, A., Virius, M., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment
Abstract: We have searched for exclusive production of exotic charmonia in the reaction $\mu^+~N \rightarrow \mu^+ (J\!/\!\psi\pi^+\pi^-)\pi^{\pm}~N'$ using COMPASS data collected with incoming muons of 160 GeV/$c$ and 200 GeV/$c$ momentum. In the $J\!/\!\psi\pi^+\pi^-$ mass distribution we observe a signal with a statistical significance of 4.1 $\sigma$. Its mass and width are consistent with those of the $X(3872)$. The shape of the $\pi^+\pi^-$ mass distribution from the observed decay into $J\!/\!\psi\pi^+\pi^-$ shows disagreement with previous observations for $X(3872)$. The observed signal may be interpreted as a possible evidence of a new charmonium state. It could be associated with a neutral partner of $X(3872)$ with $C = -1$ predicted by a tetraquark model. The product of cross section and branching fraction of the decay of the observed state into $J\!/\!\psi\pi^+\pi^-$ is determined to be 71$\pm$28(stat)$\pm$39(syst) pb., Comment: 12 pages, 6 figures
Published: 2017
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42. First measurement of transverse-spin-dependent azimuthal asymmetries in the Drell-Yan process

Author: Aghasyan, Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kveton, A., Lednev, A. A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Roskot, M., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vauth, A., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., and Ziembicki, M.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: The first measurement of transverse-spin-dependent azimuthal asymmetries in the pion-induced Drell-Yan (DY) process is reported. We use the CERN SPS 190 GeV/$c$, $\pi^{-}$ beam and a transversely polarized ammonia target. Three azimuthal asymmetries giving access to different transverse-momentum-dependent (TMD) parton distribution functions (PDFs) are extracted using dimuon events with invariant mass between 4.3 GeV/$c^2$ and 8.5 GeV/$c^2$. The observed sign of the Sivers asymmetry is found to be consistent with the fundamental prediction of Quantum Chromodynamics (QCD) that the Sivers TMD PDFs extracted from DY have a sign opposite to the one extracted from semi-inclusive deep-inelastic scattering (SIDIS) data. We present two other asymmetries originating from the pion Boer-Mulders TMD PDFs convoluted with either the nucleon transversity or pretzelosity TMD PDFs. These DY results are obtained at a hard scale comparable to that of a recent COMPASS SIDIS measurement and hence allow unique tests of fundamental QCD universality predictions., Comment: 11 pages, 6 figures
Published: 2017
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43. A Glimpse of Gluons through Deeply Virtual Compton Scattering on the Proton

Author: Defurne, M., Jiménez-Argüello, A. Martì, 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., de Jager, C. W., de Leo, R., Desnault, C., Deur, A., Fassi, L. El, 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., Hyde, C. E., Iqbal, S., Itard, F., Kang, H., Kelleher, A., Keppel, C., Koirala, S., Korover, I., LeRose, J. J., Lindgren, R., Long, E., Magne, M., Mammei, J., Margaziotis, D. J., Markowitz, P., Mazouz, M., Meddi, F., Meekins, D., Michaels, R., Mihovilovic, M., Camacho, C. Munoz, 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., Zhan, X., Zhang, J., Zhao, B., Zhao, Z., Zheng, X., and Zhu, P.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology, Nuclear Experiment
Abstract: The proton is composed of quarks and gluons, bound by the most elusive mechanism of strong interaction called confinement. In this work, the dynamics of quarks and gluons are investigated using deeply virtual Compton scattering (DVCS): produced by a multi-GeV electron, a highly virtual photon scatters off the proton which subsequently radiates a high energy photon. Similarly to holography, measuring not only the magnitude but also the phase of the DVCS amplitude allows to perform 3D images of the internal structure of the proton. The phase is made accessible through the quantum-mechanical interference of DVCS with the Bethe-Heitler (BH) process, in which the final photon is emitted by the electron rather than the proton. We report herein the first full determination of the BH-DVCS interference by exploiting the distinct energy dependences of the DVCS and BH amplitudes. In the high energy regime where the scattering process is expected to occur off a single quark in the proton, these accurate measurements show an intriguing sensitivity to gluons, the carriers of the strong interaction.
Published: 2017
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44. 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., Fassi, L. El, 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., Jiménez-Argüello, A. Martí, Meddi, F., Meekins, D., Michaels, R., Mihovilovic, M., Muangma, N., Camacho, C. Muñoz, 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., and Zhu, P.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
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
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45. First measurement of the Sivers asymmetry for gluons from SIDIS data

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Roskot, M., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: The Sivers function describes the correlation between the transverse spin of a nucleon and the transverse motion of its partons. It was extracted from measurements of the azimuthal asymmetry of hadrons produced in semi-inclusive deep inelastic scattering of leptons off transversely polarised nucleon targets, and it turned out to be non-zero for quarks. In this letter the evaluation of the Sivers asymmetry for gluons in the same process is presented. The analysis method is based on a Monte Carlo simulation that includes three hard processes: photon-gluon fusion, QCD Compton scattering and leading-order virtual-photon absorption process. The Sivers asymmetries of the three processes are simultaneously extracted using the LEPTO event generator and a neural network approach. The method is applied to samples of events containing at least two hadrons with large transverse momentum from the COMPASS data taken with a 160 GeV/$c$ muon beam scattered off transversely polarised deuterons and protons. With a significance of more than two standard deviations a negative value is obtained for the gluon Sivers asymmetry. The result of a similar analysis for a Collins-like asymmetry for gluons is consistent with zero., Comment: 18 pages, 8 figures
Published: 2017
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46. Final COMPASS results on the deuteron spin-dependent structure function $g_1^{\rm d}$ and the Bjorken sum rule

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., Windmolders, R., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment
Abstract: Final results are presented from the inclusive measurement of deep-inelastic polarised-muon scattering on longitudinally polarised deuterons using a $^6$LiD target. The data were taken at $160~{\rm GeV}$ beam energy and the results are shown for the kinematic range $1~({\rm GeV}/c)^2 < Q^2 < 100~({\rm GeV}/c)^2$ in photon virtuality, $0.004 4~{\rm GeV}/c^2$ in the mass of the hadronic final state. The deuteron double-spin asymmetry $A_1^{\rm d}$ and the deuteron longitudinal-spin structure function $g_1^{\rm d}$ are presented in bins of $x$ and $Q^2$. Towards lowest accessible values of $x$, $g_1^{\rm d}$ decreases and becomes consistent with zero within uncertainties. The presented final $g_1^{\rm d}$ values together with the recently published final $g_1^{\rm p}$ values of COMPASS are used to again evaluate the Bjorken sum rule and perform the QCD fit to the $g_1$ world data at next-to-leading order of the strong coupling constant. In both cases, changes in central values of the resulting numbers are well within statistical uncertainties. The flavour-singlet axial charge $a_0$, {which is identified in the $\overline{\rm MS}$ renormalisation scheme with the total contribution of quark helicities to the nucleon spin}, is extracted from only the COMPASS deuteron data with negligible extrapolation uncertainty: $a_0 (Q^2 = 3~({\rm GeV}/c)^2) = 0.32 \pm 0.02_{\rm stat} \pm0.04_{\rm syst} \pm 0.05_{\rm evol}$. Together with the recent results on the proton spin structure function $g_1^{\rm p}$, the results on $g_1^{\rm d}$ constitute the COMPASS legacy on the measurements of $g_1$ through inclusive spin-dependent deep inelastic scattering., Comment: 16 pages, 6 figures
Published: 2016
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47. Sivers asymmetry extracted in SIDIS at the hard scale of the Drell-Yan process at COMPASS

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Sozzi, F., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Proton transverse-spin azimuthal asymmetries are extracted from the COMPASS 2010 semi-inclusive hadron measurements in deep inelastic muon-nucleon scattering in those four regions of the photon virtuality $Q^2$, which correspond to the four regions of the di-muon mass $\sqrt{Q^2}$ used in the ongoing analysis of the COMPASS Drell-Yan measurements. This allows for a future direct comparison of the nucleon transverse-momentum-dependent parton distribution functions extracted from these two alternative measurements. Various two-dimensional kinematic dependences are presented for the azimuthal asymmetries induced by the Sivers transverse-momentum-dependent parton distribution function. The integrated Sivers asymmetries are found to be positive with an accuracy that appears to be sufficient to test the sign change of the Sivers function predicted by Quantum Chromodynamics., Comment: 13 pages, 6 figures
Published: 2016
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48. Azimuthal asymmetries of charged hadrons produced in high-energy muon scattering off longitudinally polarised deuterons

Author: Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Single hadron azimuthal asymmetries of positive and negative hadrons produced in muon semi-inclusive deep inelastic scattering off longitudinally polarised deuterons are determined using the 2006 COMPASS data and also combined all deuteron COMPASS data. For each hadron charge, the dependence of the azimuthal asymmetry on the hadron azimuthal angle $\phi$ is obtained by means of a five-parameter fitting function that besides a $\phi$-independent term includes four modulations predicted by theory: $\sin\phi$, $\sin 2 \phi$, $\sin 3\phi$ and $\cos\phi$. The amplitudes of the five terms have been extracted, first, for the hadrons in the whole available kinematic region. In further fits, performed for hadrons from a restricted kinematic region, the $\phi$-dependence is determined as a function of one of three variables (Bjorken-$x$, fractional energy of virtual photon taken by the outgoing hadron and hadron transverse momentum), while disregarding the others. Except the $\phi$-independent term, all the modulation amplitudes are very small, and no clear kinematic dependence could be observed within experimental uncertainties., Comment: 15 pages, 5 figures
Published: 2016
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49. Multiplicities of charged kaons from deep-inelastic muon scattering off an isoscalar target

Author: Adolph, C., Agarwala, J., Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Buechele, M., Capozza, L., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S. -U., Cicuttin, A., Crespo, M. L., Curiel, Q., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Duennweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger jr., M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giordano, F., Gnesi, I., Gorzellik, M., Grabmueller, S., Grasso, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joeorg, P., Kabuss, E., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., Windmolders, R., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., and Zink, A.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: Precise measurements of charged-kaon multiplicities in deep inelastic scattering were performed. The results are presented in three-dimensional bins of the Bjorken scaling variable x, the relative virtual-photon energy y, and the fraction z of the virtual-photon energy carried by the produced hadron. The data were obtained by the COMPASS Collaboration by scattering 160 GeV muons off an isoscalar 6 LiD target. They cover the kinematic domain 1 (GeV/c)2 < Q2 < 60 (GeV/c)^2 in the photon virtuality, 0.004 < x < 0.4, 0.1 < y < 0.7, 0.20 < z < 0.85, and W > 5 GeV/c^2 in the invariant mass of the hadronic system. The results from the sum of the z-integrated K+ and K- multiplicities at high x point to a value of the non-strange quark fragmentation function larger than obtained by the earlier DSS fit., Comment: 10 pages, 9 figures
Published: 2016
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50. Rosenbluth separation of the $\pi^0$ electroproduction cross section

Author: Defurne, M., Mazouz, M., 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., de Jager, C. W., de Leo, R., Desnault, C., Deur, A., Fassi, L. El, 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., Hyde, C. E., Iqbal, S., Itard, F., Kang, H., Kelleher, A., Keppel, C., Koirala, S., Korover, I., LeRose, J. J., Lindgren, R., Long, E., Magne, M., Mammei, J., Margaziotis, D. J., Markowitz, P., Jimenez-Arguello, A. Marti, Meddi, F., Meekins, D., Michaels, R., Mihovilovic, M., Camacho, C. Munoz, 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., Sabati, 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., Zafar, A., Zhan, X., Zhang, J., Zhao, B., Zhao, Z., Zheng, X., and Zhu, P.
Subjects: High Energy Physics - Experiment, Nuclear Experiment
Abstract: We present deeply virtual $\pi^0$ electroproduction cross-section measurements at $x_B$=0.36 and three different $Q^2$--values ranging from 1.5 to 2 GeV$^2$, obtained from experiment E07-007 that ran in the Hall A at Jefferson Lab. The Rosenbluth technique was used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component, and thus is far from the asymptotic limit predicted by perturbative Quantum Chromodynamics. An indication of a non-zero longitudinal contribution is provided by the interference term $\sigma_{LT}$ also measured. Results are compared with several models based on the leading twist approach of Generalized Parton Distributions (GPDs). In particular, a fair agreement is obtained with models where the scattering amplitude is described by a convolution of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. Therefore, neutral pion electroproduction may offer the exciting possibility of accessing transversity GPDs through experiment., Comment: Submitted to Physical Review Letters
Published: 2016
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