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358 results on '"Solvignon, P"'

1. 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

2. Novel Measurement of the Neutron Magnetic Form Factor from A=3 Mirror Nuclei

Author

Santiesteban, SN, 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, ME, Clarke, C, Covrig, S, Cruz-Torres, R, Day, D, Dutta, D, Fuchey, E, Gal, C, Garibaldi, F, Gautam, TN, Gogami, T, Gomez, J, Guèye, P, Hague, TJ, Hansen, JO, Hauenstein, F, Henry, W, Higinbotham, DW, Holt, RJ, Hyde, C, Itabashi, K, Kaneta, M, Karki, A, Katramatou, AT, Keppel, CE, King, PM, Kurbany, L, Kutz, T, Lashley-Colthirst, N, Li, WB, Liu, H, Liyanage, N, Long, E, Lovato, A, Mammei, J, Markowitz, P, McClellan, RE, Meddi, F, Meekins, D, Michaels, R, Mihovilovič, 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, S, Punjabi, V, Ransome, RD, Reimer, PE, Reinhold, J, Riordan, S, Rocco, N, Rodriguez, VM, Schmidt, A, Schmookler, B, Segarra, EP, Shahinyan, A, Širca, S, Slifer, K, Solvignon, P, Su, T, Suleiman, R, Tang, L, Tian, Y, Tireman, W, Tortorici, F, Toyama, Y, Uehara, K, Urciuoli, GM, and Votaw, D

Subjects
Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, Jefferson Lab Hall A Collaboration, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
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
2024

3. 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

4. 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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5. Proton spin structure and generalized polarizabilities in the strong quantum chromodynamics regime

Author

Ruth, D, Zielinski, R, Gu, C, Allada (Cummings), 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, CD, 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, DM, Meziani, ZE, McLean, C, Michaels, R, Mihovilovič, 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, PE, Roblin, Y, Ron, G, Rondon, O, Russo, G, Saenboonruang, K, Sawatzky, B, Shahinyan, A, Shneor, R, Širca, S, Sjoegren, J, Solvignon-Slifer, P, Sparveris, N, Sulkosky, V, Wesselmann, F, Yan, W, Yang, H, Yao, H, Ye, Z, Yurov, M, Zhang, Y, Zhao, YX, and Zheng, X

Subjects
Mathematical Sciences, Physical Sciences, Fluids & Plasmas
Abstract

The strong interaction is not well understood at low energies or for interactions with low momentum transfer. Chiral perturbation theory gives testable predictions for the nucleonic generalized polarizabilities, which are fundamental quantities describing the nucleon’s response to an external field. We report a measurement of the proton’s generalized spin polarizabilities extracted with a polarized electron beam and a polarized solid ammonia target in the region where chiral perturbation theory is expected to be valid. The investigated structure function g2 characterizes the internal spin structure of the proton. From its moments, we extract the longitudinal–transverse spin polarizability δLT and twist-3 matrix element and polarizability d2¯. Our results provide discriminating power between existing chiral perturbation theory calculations and will help provide a better understanding of this strong quantum chromodynamics regime.

Published
2022

6. 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

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

Author

Li, S, Cruz-Torres, R, Santiesteban, N, Ye, ZH, 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, ME, Clarke, C, Covrig, S, Craycraft, K, Day, D, Dutta, D, Fuchey, E, Gal, C, Garibaldi, F, Gautam, TN, Gogami, T, Gomez, J, Guèye, P, Habarakada, A, Hague, TJ, Hansen, JO, Hauenstein, F, Henry, W, Higinbotham, DW, Holt, RJ, Hyde, C, Itabashi, T, Kaneta, M, Karki, A, Katramatou, AT, Keppel, CE, Khachatryan, M, Khachatryan, V, King, PM, Korover, I, Kurbany, L, Kutz, T, Lashley-Colthirst, N, Li, WB, Liu, H, Liyanage, N, Long, E, Mammei, J, Markowitz, P, McClellan, RE, 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, RD, Reimer, PE, Reinhold, J, Riordan, S, Roche, J, Rodriguez, VM, Schmidt, A, Schmookler, B, Segarra, EP, Shahinyan, A, Slifer, K, Solvignon, P, and Širca, S

Subjects
Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, General Science & Technology
Abstract

When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough 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 structure1-3, and mapping out the strength and the isospin structure (neutron-proton (np) versus proton-proton (pp) pairs) of these virtual excitations is thus critical input for modelling a range of nuclear, particle and astrophysics measurements3-5. Two-nucleon knockout or 'triple coincidence' reactions have been used to measure the relative contribution of np-SRCs and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurements6-8 have shown that SRCs are almost exclusively np pairs, but they had limited statistics and required large model-dependent final-state interaction corrections. Here we report on measurements using inclusive scattering from the mirror nuclei hydrogen-3 and helium-3 to extract the np/pp ratio of SRCs in systems with a mass number of three. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a marked deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for hydrogen-3 and helium-3. Understanding these results will improve our understanding of the short-range part of the nucleon-nucleon interaction.

Published
2022

8. First Determination of the 27Al Neutron Distribution Radius from a Parity-Violating Electron Scattering Measurement

Author

QWeak Collaboration, Androic, D., Armstrong, D. S., Bartlett, K., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cornejo, J. C., Dusa, S. Covrig, Dalton, M. M., Davis, C. A., Deconinck, W., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Elaasar, M., Falk, W. R., Finn, J. M., Forest, T., Gal, C., Gaskell, D., Gericke, M. T. W., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Jones, D. C., Jones, M. K., Kargiantoulakis, M., King, P. M., Korkmaz, E., Kowalski, S., Leacock, J., Leckey, J., Lee, A. R., Lee, J. H., Lee, L., MacEwan, S., Mack, D., Magee, J. A., Mahurin, R., Mammei, J., Martin, J. W., McHugh, M. J., Meekins, D., Mei, J., Mesick, K. E., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Narayan, A., Ndukum, L. Z., Nelyubin, V., Nuruzzaman, van Oers, W. T. H, Owen, V. F., Page, S. A., Pan, J., Paschke, K. D., Phillips, S. K., Pitt, M. L., Radloff, R. W., Rajotte, J. F., Ramsay, W. D., Roche, J., Sawatzky, B., Seva, T., Shabestari, M. H., Silwal, R., Simicevic, N., Smith, G. R., Solvignon, P., Spayde, D. T., Subedi, A., Subedi, R., Suleiman, R., Tadevosyan, V., Tobias, W. A., Tvaskis, V., Waidyawansa, B., Wang, P., Wells, S. P., Wood, S. A., Yang, S., Zang, P., Zhamkochyan, S., Christy, M. E., Horowitz, C. J., Fattoyev, F. J., and Lin, Z.

Subjects
Nuclear Experiment
Abstract

We report the first measurement of the parity-violating elastic electron scattering asymmetry on 27Al. The 27Al elastic asymmetry is A_PV = 2.16 +- 0.11 (stat) +- 0.16 (syst) ppm, and was measured at =0.02357 +- 0.0001 GeV^2, = 7.61 +- 0.02 degrees, and = 1.157 GeV with the Qweak apparatus at Jefferson Lab. Predictions using a simple Born approximation as well as more sophisticated distorted-wave calculations are in good agreement with this result. From this asymmetry the 27Al neutron radius R_n = 2.89 +- 0.12 fm was determined using a many-models correlation technique. The corresponding neutron skin thickness R_n-R_p = -0.04 +- 0.12 fm is small, as expected for a light nucleus with a neutron excess of only 1. This result thus serves as a successful benchmark for electroweak determinations of neutron radii on heavier nuclei. A tree-level approach was used to extract the 27Al weak radius R_w = 3.00 +- 0.15 fm, and the weak skin thickness R_wk - R_ch = -0.04 +- 0.15 fm. The weak form factor at this Q^2 is F_wk = 0.39 +- 0.04., Comment: Revised version after referee's comments and suggestions. Some improvements and clarification to the text, no changes to the figures, tables, results or conclusions. 7 pages, 3 figures, 3 tables

Published
2021
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9. Probing for high-momentum protons in He4 via the He4(e,e′p)X reactions

Author

Iqbal, S, Benmokhtar, F, Ivanov, M, See, N, Aniol, K, Higinbotham, DW, Boyd, C, Gadsby, A, Goodwill, JS, Finton, D, Boyer, A, Gilad, S, Saha, A, Udias, JM, 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, MM, 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, Guèye, 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, DJ, 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, PE, 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, JW, and Weinstein, LB

Subjects
Nuclear and Plasma Physics, Physical Sciences, Nuclear and plasma physics
Abstract

Experimental cross sections for the He4(e,e′p)X reactions in the missing energy range from 0.017 to 0.022 GeV and up to a missing momentum of 0.632 GeV/c at xB=1.24 and Q2=2 (GeV/c)2 are reported. The data are compared to relativistic distorted-wave impulse approximation calculations for the He4(e,e′p)H3 channel. Significantly more events are observed for pm≥0.45 GeV/c than are predicted by the theoretical model, and striking fluctuations in the ratio of data to the theoretical model around pm=0.3GeV/c are possible signals of initial-state multinucleon correlations.

Published
2022

10. Measurement of the EMC effect in light and heavy nuclei

Author

Arrington, J., Bane, J., Daniel, A., Fomin, N., Gaskell, D., Seely, J., Asaturyan, R., Benmokhtar, F., Boeglin, W., Bosted, P., Bukhari, M. H. S., Christy, M. E., Connell, S., Dalton, M. M., Day, D., Dunne, J., Dutta, D., Fassi, L. El, Ent, R., Fenker, H., Gao, H., Holt, R. J., Horn, T., Hungerford, E., Jones, M. K., Jourdan, J., Kalantarians, N., Keppel, C. E., Kiselev, D., Lung, A. F., Malace, S., Meekins, D. G., Mertens, T., Mkrtchyan, H., Niculescu, G., Niculescu, I., Potterveld, D. H., Perdrisat, C., Punjabi, V., Qian, X., Reimer, P. E., Roche, J., Rodriguez, V. M., Rondon, O., Schulte, E., Slifer, K., Smith, G. R., Solvignon, P., Tadevosyan, V., Tang, L., Testa, G., Trojer, R., Tvaskis, V., Wesselmann, F. R., Wood, S. A., Yuan, L., and Zheng, X.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

Inclusive electron scattering from nuclear targets has been measured to extract the nuclear dependence of the inelastic cross section in Hall C at the Thomas Jefferson National Accelerator facility. Results are presented for 2H, 3He, 4He, 9B, 12C, 63Cu and 197Au at an incident electron beam energy of 5.77 GeV for a range of momentum transfer from Q^2 = 2 to 7 (GeV/c)^2. These data improve the precision of the existing measurements of the EMC effect in the nuclear targets at large x, and allow for more detailed examinations of the A dependence of the EMC effect., Comment: 28 pages, 23 figures, archival paper for Jefferson Lab experiment E03-103

Published
2021
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11. 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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12. Measurement of the Beam-Normal Single-Spin Asymmetry for Elastic Electron Scattering from $^{12}$C and $^{27}$Al

Author

QWeak Collaboration, Androic, D., Armstrong, D. S., Asaturyan, A., Bartlett, K., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Christy, M. E., Cornejo, J. C., Dusa, S. Covrig, Dalton, M. M., Davis, C. A., Deconinck, W., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Elassar, M., Falk, W. R., Finn, J. M., Forest, T., Gal, C., Gaskell, D., Gericke, M. T. W., Gray, V. M., Guo, F., Hoskins, J. R., Jones, D. C., Kargiantoulakis, M., King, P. M., Korkmaz, E., Kowalski, S., Leacock, J., Leckey, J. P., Lee, A. R., Lee, J. H., Lee, L., MacEwan, S., Mack, D., Magee, J. A., Mahurin, R., Mammei, J., Martin, J. W., McHugh, M. J., Meekins, D., Mesick, K. E., Michaels, R., Mkrtchyan, A., Mkrtchyan, H., Narayan, A., Ndukum, L. Z., Nuruzzaman, Nelyubin, V., van Oers, W. T. H, Owen, V. F., Page, S. A., Pan, J., Paschke, K. D., Phillips, S. K., Pitt, M. L., Radloff, R. W., Rajotte, J. F., Ramsay, W. D., Roche, J., Sawatzky, B., Seva, T., Shabestari, M. H., Silwal, R., Simicevic, N., Smith, G. R., Solvignon, P., Spayde, D. T., Subedi, A., Subedi, R., Tadevosyan, V., Tobias, W. A., Waidyawansa, B., Wang, P., Wells, S. P., Wood, S. A., Zang, P., and Zhamkochyan, S.

Subjects
Nuclear Experiment
Abstract

We report measurements of the parity-conserving beam-normal single-spin elastic scattering asymmetries $B_n$ on $^{12}$C and $^{27}$Al, obtained with an electron beam polarized transverse to its momentum direction. These measurements add an additional kinematic point to a series of previous measurements of $B_n$ on $^{12}$C and provide a first measurement on $^{27}$Al. The experiment utilized the Qweak apparatus at Jefferson Lab with a beam energy of 1.158 GeV. The average lab scattering angle for both targets was 7.7 degrees, and the average $Q^2$ for both targets was 0.02437 GeV$^2$ (Q=0.1561 GeV). The asymmetries are $B_n$ = -10.68 $\pm$ 0.90 stat) $\pm$ 0.57 (syst) ppm for $^{12}$C and $B_n$ = -12.16 $\pm$ 0.58 (stat) $\pm$ 0.62 (syst) ppm for $^{27}$Al. The results are consistent with theoretical predictions, and are compared to existing data. When scaled by Z/A, the Q-dependence of all the far-forward angle (theta < 10 degrees) data from $^{1}$H to $^{27}$Al can be described by the same slope out to $Q \approx 0.35$ GeV. Larger-angle data from other experiments in the same Q range are consistent with a slope about twice as steep., Comment: Minor changes after refereeing; version as accepted for Physical Review C. Cosmetic changes to several figures, one author added. 22 pages, 8 figures

Published
2021
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13. Measurement of the generalized spin polarizabilities of the neutron in the low $Q^2$ region

Author

Sulkosky, V., Peng, C., Chen, J. -P., Deur, A., Abrahamyan, S., Aniol, K. A., Armstrong, D. S., Averett, T., Bailey, S. L., Beck, A., Bertin, P., Butaru, F., Boeglin, W., Camsonne, A., Cates, G. D., Chang, C. C., Choi, Seonho, Chudakov, E., Coman, L., Cornejo, J. C, Craver, B., Cusanno, F., De Leo, R., de Jager, C. W., Denton, J. D., Dhamija, S., Feuerbach, R., Finn, J. M., Frullani, S., Fuoti, K., Gao, H., Garibaldi, F., Gayou, O., Gilman, R., Glamazdin, A., Glashausser, C., Gomez, J., Hansen, J. -O., Hayes, D., Hersman, B., Higinbotham, D. W., Holmstrom, T., Humensky, T. B., Hyde, C. E., Ibrahim, H., Iodice, M., Jiang, X., Kaufman, L. J., Kelleher, A., Keister, K. E., Kim, W., Kolarkar, A., Kolb, N., Korsch, W., Kramer, K., Kumbartzki, G., Lagamba, L., Laine, V., Laveissiere, G., Lerose, J. J., Lhuillier, D., Lindgren, R., Liyanage, N., Lu, H. -J., Ma, B., Margaziotis, D. J., Markowitz, P., McCormick, K., Meziane, M., Meziani, Z. -E., Michaels, R., Moffit, B., Monaghan, P., Nanda, S., Niedziela, J., Niskin, M., Pandolfi, R., Paschke, K. D., Potokar, M., Puckett, A., Punjabi, V. A., Qiang, Y., Ransome, R., Reitz, B., Roche, R., Saha, A., Shabetai, A., Sirca, S., Singh, J. T., Slifer, K., Snyder, R., Solvignon, P., Stringer, R., Subedi, R., Tobias, W. A., Ton, N., Ulmer, P. E., Urciuoli, G. M., Vacheret, A., Voutier, E., Wang, K., Wan, L., Wojtsekhowski, B., Woo, S., Yao, H., Yuan, J., Zhan, X., Zheng, X., and Zhu, L.

Subjects
Nuclear Experiment
Abstract

Understanding the nucleon spin structure in the regime where the strong interaction becomes truly strong poses a challenge to both experiment and theory. At energy scales below the nucleon mass of about 1 GeV, the intense interaction among the quarks and gluons inside the nucleon makes them highly correlated. Their coherent behaviour causes the emergence of effective degrees of freedom, requiring the application of non-perturbative techniques, such as chiral effective field theory. Here, we present measurements of the neutron's generalized spin-polarizabilities that quantify the neutron's spin precession under electromagnetic fields at very low energy-momentum transfer squared down to 0.035 GeV$^2$. In this regime, chiral effective field theory calculations are expected to be applicable. Our data, however, show a strong discrepancy with these predictions, presenting a challenge to the current description of the neutron's spin properties., Comment: V1: initial version submitted to Nature Physics. V2: Published version. 16 pages, 7 figures. Additional material: 4 data tables (18 pages) V3: Typo corrected in author list. Paper content unchanged

Published
2021
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14. Measurement of the EMC effect in light and heavy nuclei

Author

Arrington, J, Bane, J, Daniel, A, Fomin, N, Gaskell, D, Seely, J, Asaturyan, R, Benmokhtar, F, Boeglin, W, Bosted, P, Bukhari, MHS, Christy, ME, Connell, S, Dalton, MM, Day, D, Dunne, J, Dutta, D, Fassi, L El, Ent, R, Fenker, H, Gao, H, Holt, RJ, Horn, T, Hungerford, E, Jones, MK, Jourdan, J, Kalantarians, N, Keppel, CE, Kiselev, D, Lung, AF, Malace, S, Meekins, DG, Mertens, T, Mkrtchyan, H, Niculescu, G, Niculescu, I, Potterveld, DH, Perdrisat, C, Punjabi, V, Qian, X, Reimer, PE, Roche, J, Rodriguez, VM, Rondon, O, Schulte, E, Slifer, K, Smith, GR, Solvignon, P, Tadevosyan, V, Tang, L, Testa, G, Trojer, R, Tvaskis, V, Wesselmann, FR, Wood, SA, Yuan, L, and Zheng, X

Subjects
Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, Nuclear and plasma physics
Abstract

Inclusive electron scattering from nuclear targets has been measured to extract the nuclear dependence of the inelastic cross section (σA) in Hall C at the Thomas Jefferson National Accelerator facility. Results are presented for H2, He3, He4, B9, C12, Cu63, and Au197 at an incident electron beam energy of 5.77 GeV for a range of momentum transfer from Q2 = 2 to 7 (GeV/c)2. These data improve the precision of the existing measurements of the EMC effect in the nuclear targets at large x and allow for more detailed examinations of the A dependence of the EMC effect.

Published
2021

15. Precision Measurement of the Beam-Normal Single-Spin Asymmetry in Forward-Angle Elastic Electron-Proton Scattering

Author

QWeak collaboration, Androic, D., Armstrong, D. S., Asaturyan, A., Bartlett, K., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cornejo, J. C., Dusa, S. Covrig, Dalton, M. M., Davis, C. A., Deconinck, W., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Elaasar, M., Falk, W. R., Finn, J. M., Forest, T., Gal, C., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Jones, D., Jones, M. K., Jones, R. T., Kargiantoulakis, M., King, P. M., Korkmaz, E., Kowalski, S., Leacock, J., Leckey, J. P., Lee, A. R., Lee, J. H., Lee, L., MacEwan, S., Mack, D., Magee, J. A., Mahurin, R., Mammei, J., Martin, J. W., McHugh, M. J., Meekins, D., Mei, J., Mesick, K. E., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Narayan, A., Ndukum, L. Z., Nelyubin, V., Nuruzzaman, van Oers, W. T. H, Owen, V. F., Page, S. A., Pan, J., Paschke, K. D., Phillips, S. K., Pitt, M. L., Radloff, R. W., Rajotte, J. F., Ramsay, W. D., Roche, J., Sawatzky, B., Seva, T., Shabestari, M. H., Silwal, R., Simicevic, N., Smith, G. R., Solvignon, P., Spayde, D. T., Subedi, A., Subedi, R., Suleiman, R., Tadevosyan, V., Tobias, W. A., Tvaskis, V., Waidyawansa, B., Wang, P., Wells, S. P., Wood, S. A., Yang, S., Zang, P., and Zhamkochyan, S.

Subjects
Nuclear Experiment
Abstract

A beam-normal single-spin asymmetry generated in the scattering of transversely polarized electrons from unpolarized nucleons is an observable related to the imaginary part of the two-photon exchange process. We report a 2% precision measurement of the beam-normal single-spin asymmetry in elastic electron-proton scattering with a mean scattering angle of theta_lab = 7.9 degrees and a mean energy of 1.149 GeV. The asymmetry result is B_n = -5.194 +- 0.067 (stat) +- 0.082 (syst) ppm. This is the most precise measurement of this quantity available to date and therefore provides a stringent test of two-photon exchange models at far-forward scattering angles (theta_lab -> 0) where they should be most reliable., Comment: 6 pages, 3 figures; Slightly revised version, after referee's comments; accepted in PRL

Published
2020
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16. 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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17. Measurement of the beam-normal single-spin asymmetry for elastic electron scattering from C12 and Al27

Author

Androić, D, Armstrong, DS, Asaturyan, A, Bartlett, K, Beminiwattha, RS, Benesch, J, Benmokhtar, F, Birchall, J, Carlini, RD, Christy, ME, Cornejo, JC, Dusa, S Covrig, Dalton, MM, Davis, CA, Deconinck, W, Dowd, JF, Dunne, JA, Dutta, D, Duvall, WS, Elaasar, M, Falk, WR, Finn, JM, Forest, T, Gal, C, Gaskell, D, Gericke, MTW, Gray, VM, Guo, F, Hoskins, JR, Jones, DC, Kargiantoulakis, M, King, PM, Korkmaz, E, Kowalski, S, Leacock, J, Leckey, JP, Lee, AR, Lee, JH, Lee, L, MacEwan, S, Mack, D, Magee, JA, Mahurin, R, Mammei, J, Martin, JW, McHugh, MJ, Meekins, D, Mesick, KE, Michaels, R, Mkrtchyan, A, Mkrtchyan, H, Narayan, A, Ndukum, LZ, Nelyubin, V, Nuruzzaman, van Oers, WTH, Owen, VF, Page, SA, Pan, J, Paschke, KD, Phillips, SK, Pitt, ML, Radloff, RW, Rajotte, JF, Ramsay, WD, Roche, J, Sawatzky, B, Seva, T, Shabestari, MH, Silwal, R, Simicevic, N, Smith, GR, Solvignon, P, Spayde, DT, Subedi, A, Subedi, R, Suleiman, R, Tadevosyan, V, Tobias, WA, Tvaskis, V, Waidyawansa, B, Wang, P, Wells, SP, Wood, SA, Zang, P, and Zhamkochyan, S

Subjects
Clinical Research, nucl-ex
Abstract

We report measurements of the parity-conserving beam-normal single-spinelastic scattering asymmetries $B_n$ on $^{12}$C and $^{27}$Al, obtained withan electron beam polarized transverse to its momentum direction. Thesemeasurements add an additional kinematic point to a series of previousmeasurements of $B_n$ on $^{12}$C and provide a first measurement on $^{27}$Al.The experiment utilized the Qweak apparatus at Jefferson Lab with a beam energyof 1.158 GeV. The average lab scattering angle for both targets was 7.7degrees, and the average $Q^2$ for both targets was 0.02437 GeV$^2$ (Q=0.1561GeV). The asymmetries are $B_n$ = -10.68 $\pm$ 0.90 stat) $\pm$ 0.57 (syst) ppmfor $^{12}$C and $B_n$ = -12.16 $\pm$ 0.58 (stat) $\pm$ 0.62 (syst) ppm for$^{27}$Al. The results are consistent with theoretical predictions, and arecompared to existing data. When scaled by Z/A, the Q-dependence of all thefar-forward angle (theta < 10 degrees) data from $^{1}$H to $^{27}$Al can bedescribed by the same slope out to $Q \approx 0.35$ GeV. Larger-angle data fromother experiments in the same Q range are consistent with a slope about twiceas steep.

Published
2021

18. 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, JP, Chirapatpimol, K, Cisbani, E, Dalton, MM, 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, JO, Shabestari, MH, Higinbotham, DW, Huang, M, Iqbal, S, Jin, G, Kalantarians, N, Kang, H, Kelleher, A, Korover, I, Lerose, J, Leckey, J, Li, S, Lindgren, R, Long, E, Mammei, J, Margaziotis, DJ, Markowitz, P, Meekins, D, Meziani, ZE, Michaels, R, Mihovilovic, M, Muangma, N, Camacho, CM, Norum, BE, Nuruzzaman, Pan, K, Phillips, S, Piasetzky, E, Pomerantz, I, Posik, M, Punjabi, V, Qian, X, Qiang, Y, Qiu, X, Reimer, PE, Rakhman, A, Riordan, S, Ron, G, Rondon-Aramayo, O, Saha, A, Selvy, L, Shahinyan, A, Shneor, R, Širca, S, Slifer, K, Solvignon, P, Sparveris, N, Subedi, R, Sulkosky, V, Wang, D, Watson, JW, Weinstein, LB, Wojtsekhowski, B, Wood, SA, Yaron, I, Zhan, X, Zhang, J, and Zhang, YW

Subjects
nucl-ex
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 Ca48 to Ca40 in a kinematic region dominated by SRCs we provide a new way to study the isospin structure of SRCs.

Published
2020

19. Parity-Violating Inelastic Electron-Proton Scattering at Low $Q^2$ Above the Resonance Region

Author

QWeak Collaboration, Androic, D., Armstrong, D. S., Asaturyan, A., Bartlett, K., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cornejo, J. C., Dalton, M. M., Davis, C. A., Deconinck, W., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Falk, W. R., Finn, J. M., Gal, C., Gaskell, D., Gericke, M. T. W., Grames, J., Guo, F., Hoskins, J. R., Jones, D., Jones, M. K., Jones, R., Kargiantoulakis, M., King, P. M., Korkmaz, E., Kowalski, S., Leacock, J., Lee, A. R., Lee, J. H., Lee, L., MacEwan, S., Mack, D., Magee, J. A., Mammei, J., Martin, J. W., McHugh, M. J., Meekins, D., Mesick, K. E., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Narayan, A., Nelyubin, V., van Oers, W. T. H, Owen, V. F., Page, S. A., Pan, J., Paschke, K. D., Phillips, S. K., Pitt, M. L., Radloff, R. W., Ramsay, W. D., Roche, J., Sawatzky, B., Seva, T., Shabestari, M. H., Silwal, R., Simicevic, N., Smith, G. R., Solvignon, P., Spayde, D. T., Subedi, A., Tadevosyan, V., Waidyawansa, B., Wang, P., Wells, S. P., Wood, S. A., and Zang, P.

Subjects
Nuclear Experiment, High Energy Physics - Phenomenology
Abstract

We report the measurement of the parity-violating asymmetry for the inelastic scattering of electrons from the proton, at $Q^2 = 0.082$ GeV$^2$ and $ W = 2.23$ GeV, above the resonance region. The result $A_{\rm Inel} = - 13.5 \pm 2.0 ({\rm stat}) \pm 3.9 ({\rm syst})$~ppm agrees with theoretical calculations, and helps to validate the modeling of the $\gamma Z$ interference structure functions $F_1^{\gamma Z}$ and $F_2^{\gamma Z}$ used in those calculations, which are also used for determination of the two-boson exchange box diagram ($\Box_{\gamma Z}$) contribution to parity-violating elastic scattering measurements. A positive parity-violating asymmetry for inclusive $\pi^-$ production was observed, as well as positive beam-normal single-spin asymmetry for scattered electrons and a negative beam-normal single-spin asymmetry for inclusive $\pi^-$ production., Comment: 18 pages, 9 figures, version accepted in Physical Review C

Published
2019
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20. Measurement of the 3He Spin-Structure Functions and of Neutron (3He) Spin-Dependent Sum Rules at 0.035<Q^2<0.24 GeV^2

Author

Sulkosky, V., Singh, J. T., Peng, C., Chen, J. -P., Deur, A., Abrahamyan, S., Aniol, K. A., Armstrong, D. S., Averett, T., Bailey, S. L., Beck, A., Bertin, P., Butaru, F., Boeglin, W., Camsonne, A., Cates, G. D., Chang, C. C., Choi, Seonho, Chudakov, E., Coman, L., Cornejo, J. C, Craver, B., Cusanno, F., De Leo, R., de Jager, C. W., Denton, J. D., Dhamija, S., Feuerbach, R., Finn, J. M., Frullani, S., Fuoti, K., Gao, H., Garibaldi, F., Gayou, O., Gilman, R., Glamazdin, A., Glashausser, C., Gomez, J., Hansen, J. -O., Hayes, D., Hersman, B., Higinbotham, D. W., Holmstrom, T., Humensky, T. B., Hyde, C. E., Ibrahim, H., Iodice, M., Jiang, X., Kaufman, L. J., Kelleher, A., Keister, K. E., Kim, W., Kolarkar, A., Kolb, N., Korsch, W., Kramer, K., Kumbartzki, G., Lagamba, L., Laine, V., Laveissiere, G., Lerose, J. J., Lhuillier, D., Lindgren, R., Liyanage, N., Lu, H. -J., Ma, B., Margaziotis, D. J., Markowitz, P., McCormick, K., Meziane, M., Meziani, Z. -E., Michaels, R., Moffit, B., Monaghan, P., Nanda, S., Niedziela, J., Niskin, M., Pandolfi, R., Paschke, K. D., Potokar, M., Puckett, A., Punjabi, V. A., Qiang, Y., Ransome, R., Reitz, B., Roche, R., Saha, A., Shabetai, A., Sirca, S., Slifer, K., Snyder, R., Solvignon, P., Stringer, R., Subedi, R., Tobias, W. A., Ton, N., Ulmer, P. E., Urciuoli, G. M., Vacheret, A., Voutier, E., Wang, K., Wan, L., Wojtsekhowski, B., Woo, S., Yao, H., Yuan, J., Zhan, X., Zheng, X., and Zhu, L.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

The spin-structure functions $g_1$ and $g_2$, and the spin-dependent partial cross-section $\sigma_\mathrm{TT}$ have been extracted from the polarized cross-sections differences, $\Delta \sigma_{\parallel}\hspace{-0.06cm}\left(\nu,Q^{2}\right)$ and $\Delta \sigma_{\perp}\hspace{-0.06cm}\left(\nu,Q^{2}\right)$ measured for the $\vec{^\textrm{3}\textrm{He}}(\vec{\textrm{e}},\textrm{e}')\textrm{X}$ reaction, in the E97-110 experiment at Jefferson Lab. Polarized electrons with energies from 1.147 to 4.404 GeV were scattered at angles of 6$^{\circ}$ and 9$^{\circ}$ from a longitudinally or transversely polarized $^{3}$He target. The data cover the kinematic regions of the quasi-elastic, resonance production and beyond. From the extracted spin-structure functions, the first moments $\overline{\Gamma_1}\hspace{-0.06cm}\left(Q^{2}\right)$, $\Gamma_2\hspace{-0.06cm}\left(Q^{2}\right)$ and $I_{\mathrm{TT}}\hspace{-0.06cm}\left(Q^{2}\right)$ are evaluated with high precision for the neutron in the $Q^2$ range from 0.035 to 0.24~GeV$^{2}$. The comparison of the data and the chiral effective field theory predictions reveals the importance of proper treatment of the $\Delta$ degree of freedom for spin observables., Comment: 7 pages, 5 figures, 3 tables. Version published in Phys. Lett. B

Published
2019
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21. Precision Measurement of the Weak Charge of the Proton

Author

Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T., Balewski, J., Bartlett, K., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cornejo, J. C., Dusa, S. Covrig, Dalton, M. M., Davis, C. A., Deconinck, W., Diefenbach, J., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Elaasar, M., Falk, W. R., Finn, J. M., Forest, T., Gal, C., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Jones, D., Jones, M., Jones, R., Kargiantoulakis, M., King, P. M., Korkmaz, E., Kowalski, S., Leacock, J., Leckey, J., Lee, A. R., Lee, J. H., Lee, L., MacEwan, S., Mack, D., Magee, J. A., Mahurin, R., Mammei, J., Martin, J. W., McHugh, M. J., Meekins, D., Mei, J., Mesick, K. E., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Narayan, A., Ndukum, L. Z., Nelyubin, V., Nuhait, H., Nuruzzaman, van Oers, W. T. H., Opper, A. K., Page, S. A., Pan, J., Paschke, K. D., Phillips, S. K., Pitt, M. L., Poelker, M., Rajotte, J. F., Ramsay, W. D., Roche, J., Sawatzky, B., Seva, T., Shabestari, M. H., Silwal, R., Simicevic, N., Smith, G. R., Solvignon, P., Spayde, D. T., Subedi, A., Subedi, R., Suleiman, R., Tadevosyan, V., Tobias, W. A., Tvaskis, V., Waidyawansa, B., Wang, P., Wells, S. P., Wood, S. A., Yang, S., Young, R. D., Zang, P., and Zhamkochyan, S.

Subjects
Nuclear Experiment
Abstract

The fields of particle and nuclear physics have undertaken extensive programs to search for evidence of physics beyond that explained by current theories. The observation of the Higgs boson at the Large Hadron Collider completed the set of particles predicted by the Standard Model (SM), currently the best description of fundamental particles and forces. However, the theory's limitations include a failure to predict fundamental parameters and the inability to account for dark matter/energy, gravity, and the matter-antimater asymmetry in the universe, among other phenomena. Given the lack of additional particles found so far through direct searches in the post-Higgs era, indirect searches utilizing precise measurements of well predicted SM observables allow highly targeted alternative tests for physics beyond the SM. Indirect searches have the potential to reach mass/energy scales beyond those directly accessible by today's high-energy accelerators. The value of the weak charge of the proton Q_W^p is an example of such an indirect search, as it sets the strength of the proton's interaction with particles via the well-predicted neutral electroweak force. Parity violation (invariance under spatial inversion (x,y,z) -> (-x,-y,-z)) is violated only in the weak interaction, thus providing a unique tool to isolate the weak interaction in order to measure the proton's weak charge. Here we report Q_W^p=0.0719+-0.0045, as extracted from our measured parity-violating (PV) polarized electron-proton scattering asymmetry, A_ep=-226.5+-9.3 ppb. Our value of Q_W^p is in excellent agreement with the SM, and sets multi-TeV-scale constraints on any semi-leptonic PV physics not described within the SM., Comment: Direct link to Nature Version "https://rdcu.be/954U"

Published
2019
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22. 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

23. Erratum to: Dispersive corrections in elastic electron-nucleus scattering: an investigation in the intermediate energy regime and their impact on the nuclear matter

Author

Guèye, P, Kabir, AA, Giuliani, P, Glister, J, Lee, BW, Gilman, R, Higinbotham, DW, Piasetzky, E, Ron, G, Sarty, AJ, Strauch, S, Adeyemi, A, Allada, K, Armstrong, W, Arrington, J, Arenaövel, H, Beck, A, Benmokhtar, F, Berman, BL, Boeglin, W, Brash, E, Camsonne, A, Calarco, J, Chen, JP, Choi, S, Chudakov, E, Coman, L, Craver, B, Cusanno, F, Dumas, J, Dutta, C, Feuerbach, R, Freyberger, A, Frullani, S, Garibaldi, F, Hansen, J-O, Holmstrom, T, Hyde, CE, Ibrahim, H, Ilieva, Y, Jiang, X, Jones, MK, Katramatou, AT, Kelleher, A, Khrosinkova, E, Kuchina, E, Kumbartzki, G, LeRose, JJ, Lindgren, R, Markowitz, P, Beck, S May-Tal, McCullough, E, Meekins, D, Meziane, M, Meziani, Z-E, Michaels, R, Moffit, B, Norum, BE, Petratos, GG, Oh, Y, Olson, M, Paolone, M, Paschke, K, Perdrisat, CF, Potokar, M, Pomatsalyuk, R, Pomerantz, I, Puckett, A, Punjabi, V, Qian, X, Qiang, Y, Ransome, RD, Reyhan, M, Roche, J, Rousseau, Y, Sawatzky, B, Schulte, E, Schwamb, M, Shabestari, M, Shahinyan, A, Shneor, R, Širca, S, Slifer, K, Solvignon, P, Song, J, Sparks, R, Subedi, R, Urciuoli, GM, Wang, K, Wojtsekhowski, B, Yan, X, Yao, H, Zhan, X, and Zhu, X

Subjects
Affordable and Clean Energy, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

In the original PDF online version of this article, the references 22–26 were missing.These are the missing references.

Published
2020

24. Dispersive corrections in elastic electron-nucleus scattering: an investigation in the intermediate energy regime and their impact on the nuclear matter

Author

Guèye, P, Kabir, AA, Giuliani, P, Glister, J, Lee, BW, Gilman, R, Higinbotham, DW, Piasetzky, E, Ron, G, Sarty, AJ, Strauch, S, Adeyemi, A, Allada, K, Armstrong, W, Arrington, J, Arenaövel, H, Beck, A, Benmokhtar, F, Berman, BL, Boeglin, W, Brash, E, Camsonne, A, Calarco, J, Chen, JP, Choi, S, Chudakov, E, Coman, L, Craver, B, Cusanno, F, Dumas, J, Dutta, C, Feuerbach, R, Freyberger, A, Frullani, S, Garibaldi, F, Hansen, J-O, Holmstrom, T, Hyde, CE, Ibrahim, H, Ilieva, Y, Jiang, X, Jones, MK, Katramatou, AT, Kelleher, A, Khrosinkova, E, Kuchina, E, Kumbartzki, G, LeRose, JJ, Lindgren, R, Markowitz, P, Beck, S May-Tal, McCullough, E, Meekins, D, Meziane, M, Meziani, Z-E, Michaels, R, Moffit, B, Norum, BE, Petratos, GG, Oh, Y, Olson, M, Paolone, M, Paschke, K, Perdrisat, CF, Potokar, M, Pomatsalyuk, R, Pomerantz, I, Puckett, A, Punjabi, V, Qian, X, Qiang, Y, Ransome, RD, Reyhan, M, Roche, J, Rousseau, Y, Sawatzky, B, Schulte, E, Schwamb, M, Shabestari, M, Shahinyan, A, Shneor, R, Širca, S, Slifer, K, Solvignon, P, Song, J, Sparks, R, Subedi, R, Urciuoli, GM, Wang, K, Wojtsekhowski, B, Yan, X, Yao, H, Zhan, X, and Zhu, X

Subjects
nucl-ex, nucl-th, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics
Abstract

Measurements of elastic electron scattering data within the past decade have highlighted two-photon exchange contributions as a necessary ingredient in theoretical calculations to precisely evaluate hydrogen elastic scattering cross sections. This correction can modify the cross section at the few percent level. In contrast, dispersive effects can cause significantly larger changes from the Born approximation. The purpose of this experiment is to extract the carbon-12 elastic cross section around the first diffraction minimum, where the Born term contributions to the cross section are small to maximize the sensitivity to dispersive effects. The analysis uses the LEDEX data from the high resolution Jefferson Lab Hall A spectrometers to extract the cross sections near the first diffraction minimum of 12C at beam energies of 362 MeV and 685 MeV. The results are in very good agreement with previous world data, although with less precision. The average deviation from a static nuclear charge distribution expected from linear and quadratic fits indicate a 30.6% contribution of dispersive effects to the cross section at 1 GeV. The magnitude of the dispersive effects near the first diffraction minimum of 12C has been confirmed to be large with a strong energy dependence and could account for a large fraction of the magnitude for the observed quenching of the longitudinal nuclear response. These effects could also be important for nuclei radii extracted from parity-violating asymmetries measured near a diffraction minimum.

Published
2020

25. High-resolution hypernuclear spectroscopy at Jefferson Lab, Hall A

Author

Jefferson Lab Hall A Collaboration, Garibaldi, F., Acha, A., Ambrozewicz, P., Aniol, K. A., Beturin, P., Benaoum, H., Benesch, J., Bertin, P. Y., Blomqvist, K. I., Boeglin, W. U., Breuer, H., Brindza, P., Bydzovsky, P., Camsonne, A., Chang, C. C., Chen, J. -P., Choi, Seonho, Chudakov, E. A., Cisbani, E., Colilli, S., Coman, L., Cusanno, F., Craver, B. J., De Cataldo, G., de Jager, C. W., De Leo, R., Deur, A. P., Ferdi, C., Feuerbach, R. J., Folts, E., Frullani, S., Gayou, O., Giuliani, F., Gomez, J., Gricia, M., Hansen, J. O., Hayes, D., Higinbotham, D. W., Holmstrom, T. K., Hyde, C. E., Ibrahim, H. F., Iodice, M., Jiang, X., Kaufman, L. J., Kino, K., Kross, B., Lagamba, L., LeRose, J. J., Lindgren, R. A., Lucentini, M., Margaziotis, D. J., Markowitz, P., Marrone, S., Meekins, D. G., Meziani, Z. E., McCormick, K., Michaels, R. W., Millener, D. J., Miyoshi, T., Moffit, B., Monaghan, P. A., Moteabbed, M., Camacho, C. Munoz, Nanda, S., Nappi, E., Nelyubin, V. V., Norum, B. E., Okasyasu, Y., Paschke, K. D., Perdrisat, C. F., Piasetzky, E., Punjabi, V. A., Qiang, Y., Raue, B., Reimer, P. E., Reinhold, J., Reitz, B., Roche, R. E., Rodriguez, V. M., Saha, A., Santavenere, F., Sarty, A. J., Segal, J., Shahinyan, A., Singh, J., Sirca, S., Snyder, R., Solvignon, P. H., Sotona, M., Subedi, R., Sulkosky, V. A., Suzuki, T., Ueno, H., Ulmer, P. E., Urciuoli, G. M., Voutier, E., Wojtsekhowski, B. B., Zheng, X., and Zorn, C.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

The experiment E94-107 in Hall A at Jefferson Lab started a systematic study of high resolution hypernuclear spectroscopy in the 0p-shell region of nuclei such as the hypernuclei produced in electroproduction on 9Be, 12C and 16O targets. In order to increase counting rates and provide unambiguous kaon identification two superconducting septum magnets and a ring-imaging Cherenkov detector were added to the Hall A standard equipment. The high-quality beam, the good spectrometers and the new experimental devices allowed us to obtain very good results. For the first time, measurable strength with sub-MeV energy resolution was observed for the core-excited states of Lambda 12B. A high-quality Lambda 16N hypernuclear spectrum was likewise obtained. A first measurement of the Lambda binding energy for Lambda 16N, calibrated against the elementary reaction on hydrogen, was obtained with high precision, 13.76 +/- 0.16 MeV. Similarly, the first Lambda 9Li hypernuclear spectrum shows general agreement with theory (distorted-wave impulse approximation with the SLA and BS3 electroproduction models and shell-model wave functions). Some disagreement exists with respect to the relative strength of the states making up the first multiplet. A Lambda separation energy of 8.36 MeV was obtained, in agreement with previous results. It has been shown that the electroproduction of hypernuclei can provide information complementary to that obtained with hadronic probes and the gamma-ray spectroscopy technique., Comment: 27 pages, 18 figures, submitted to Physical Review C

Published
2018
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26. Measurements of Non-Singlet Moments of the Nucleon Structure Functions and Comparison to Predictions from Lattice QCD for $Q^2 = 4$ $\rm GeV^2$

Author

Albayrak, I., Mamyan, V., Christy, M. E., Ahmidouch, A., Arrington, J., Asaturyan, A., Bodek, A., Bosted, P., Bradford, R., Brash, E., Bruell, A., Butuceanu, C, Coleman, S. J., Commisso, M., Connell, S. H., Dalton, M. M., Danagoulian, S., Daniel, A., Day, D. B., Dhamija, S., Dunne, J., Dutta, D., Ent, R., Gaskell, D., Gasparian, A., Gran, R., Horn, T., Huang, Liting, Huber, G. M., Jayalath, C., Johnson, M., Jones, M. K., Kalantarians, N., Liyanage, A., Keppel, C. E., Kinney, E., Li, Y., Malace, S., Manly, S., Markowitz, P., Maxwell, J., Mbianda, N. N., McFarland, K. S., Meziane, M., Meziani, Z. E., Mills, G. B, Mkrtchyan, H., Mkrtchyan, A., Mulholland, J., Nelson, J., Niculescu, G., Niculescu, I., Pentchev, L., Puckett, A., Punjabi, V., Qattan, I. A., Reimer, P. E., Reinhold, J., Rodriguez, V. M, Rondon-Aramayo, O., Sakuda, M., Sakumoto, W. K., Segbefia, E., Seva, T., Sick, I., Slifer, K., Smith, G. R, Steinman, J., Solvignon, P., Tadevosyan, V., Tajima, S., Tvaskis, V., Smith, G. R., Vulcan, W. F., Walton, T., Wesselmann, F. R, Wood, S. A., and Ye, Zhihong

Subjects
Nuclear Experiment
Abstract

We present extractions of the nucleon non-singlet moments utilizing new precision data on the deuteron $F_2$ structure function at large Bjorken-$x$ determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world data sets on the proton and deuteron at lower $x$ measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the $x$ range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high $x$ data. Moreover, recent exciting developments in Lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach which first calculates the quark distributions directly before determining moments.

Published
2018
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27. Proton Form Factor Ratio, $\mu_p G_E^p/G_M^p$ from Double Spin Asymmetry

Author

Liyanage, A., Armstrong, W., Kang, H., Maxwell, J., Mulholland, J., Ndukum, L., Ahmidouch, A., Albayrak, I., Asaturyan, A., Ates, O., Baghdasaryan, H., Boeglin, W., Bosted, P., Brash, E., Butuceanu, C., Bychkov, M., Carter, P., Chen, C., Chen, J-P., Choi, S., Christy, E., Covrig, S., Crabb, D., Danagoulian, S., Daniel, A., Davidenko, A. M., Davis, B., Day, D., Deconinck, W., Deur, A., Dunne, J., Dutta, D., Fassi, L. El, Elaasar, M., Ellis, C., Ent, R., Flay, D., Frlez, E., Gaskell, D., Geagla, O., German, J., Gilman, R., Gogami, T., Gomez, J., Goncharenko, Y. M., Hashimoto, O., Higinbotham, D., Horn, T., Huber, G. M., Jones, M., Jones, M. K., Kalantarians, N., Kang, H-K., Kawama, D., Keppel, C., Khandaker, M., Kim, Y., King, P. M., Kohl, M., Kovacs, K., Kubarovsky, V., Li, Y., Liyanage, N., Mamyan, V., Markowitz, P., Maruta, T., Melnik, Y. M., Meziani, Z-E., Mkrtchyan, A., Mkrtchyan, H., Mochalov, V. V., Monaghan, P., Narayan, A., Nakamura, S. N., Nuruzzaman, Pentchev, L., Pocanic, D., Posik, M., Puckett, A., Qiu, X., Reinhold, J., Riordan, S., Roche, J., Rondo'n, O. A., Sawatzky, B., Shabestari, M., Slifer, K., Smith, G., Soloviev, L. F., Solvignon, P., Tadevosyan, V., Tang, L., Vasiliev, A. N., Veilleux, M., Walton, T., Wesselmann, F., Wood, S. A., Yao, H., Ye, Z., and Zhu, L.

Subjects
Nuclear Experiment
Abstract

The ratio of the electric and magnetic form factor of the proton, $\mu_p G_E^p/G_M^p$, has been measured for elastic electron-proton scattering with polarized beam and target up to four-momentum transfer squared, $Q^2=5.66$ (GeV/c)$^2$ using the double spin asymmetry for target spin orientation aligned nearly perpendicular to the beam momentum direction. This measurement of $\mu_p G_E^p/G_M^p$ agrees with the $Q^2$ dependence of previous recoil polarization data and reconfirms the discrepancy at high $Q^2$ between the Rosenbluth and the polarization-transfer method with a different measurement technique and systematic uncertainties uncorrelated to those of the recoil-polarization measurements. The form factor ratio at $Q^2$=2.06 (GeV/c)$^2$ has been measured as $\mu_p G_E^p/G_M^p = 0.720 \pm 0.176_{stat} \pm 0.039_{sys}$, which is in agreement with an earlier measurement with the polarized target technique at similar kinematics. The form factor ratio at $Q^2$=5.66 (GeV/c)$^2$ has been determined as $\mu_p G_E^p/G_M^p=0.244\pm0.353_{stat}\pm0.013_{sys}$, which represents the highest $Q^2$ reach with the double spin asymmetry with polarized target to date.

Published
2018
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28. Dispersive Corrections to the Born Approximation in Elastic Electron-Nucleus Scattering in the Intermediate Energy Regime

Author

Gueye, P., Glister, A. A. Kabir J., Lee, B. W., Gilman, R., Higinbotham, D. W., Piasetzky, E., Ron, G., Sarty, A. J., Strauch, S., Adeyemi, A., Allada, K., Armstrong, W., Arrington, J., Arenhovel, H., Beck, A., Benmokhtar, F., Berman, B. L., Boeglin, W., Brash, E., Camsonne, A., Calarco, J., Chen, J. P., Choi, S., Chudakov, E., Coman, L., Craver, B., Cusanno, F., Dumas, J., Dutta, C., Feuerbach, R., Freyberger, A., Frullani, S., Garibaldi, F., Hansen, J. -O., Holmstrom, T., Hyde, C. E., Ibrahim, H., Ilieva, Y., Jiang, X., Jones, M. K., Katramatou, A. T., Kelleher, A., Khrosinkova, E., Kuchina, E., Kumbartzki, G., LeRose, J. J., Lindgren, R., Markowitz, P., Beck, S. May-Tal, McCullough, E., Meekins, D., Meziane, M., Meziani, Z. -E., Michaels, R., Moffit, B., Norum, B. E., Petratos, G. G., Oh, Y., Olson, M., Paolone, M., Paschke, K., Perdrisat, C. F., Potokar, M., Pomatsalyuk, R., Pomerantz, I., Puckett, A., Punjabi, V., Qian, X., Qiang, Y., Ransome, R. D., Reyhan, M., Roche, J., Rousseau, Y., Sawatzky, B., Schulte, E., Schwamb, M., Shabestari, M., Shahinyan, A., Shneor, R., Sirca, S., Slifer, K., Solvignon, P., Song, J., Sparks, R., Subedi, R., Urciuoli, G. M., Wang, K., Wojtsekhowski, B., Yan, X., Yao, H., Zhan, X., and Zhu, X.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

Measurements of elastic electron scattering data within the past decade have highlighted two-photon exchange contributions as a necessary ingredient in theoretical calculations to precisely evaluate hydrogen elastic scattering cross sections. This correction can modify the cross section at the few percent level. In contrast, dispersive effects can cause significantly larger changes from the Born approximation. The purpose of this experiment is to extract the carbon-12 elastic cross section around the first diffraction minimum, where the Born term contributions to the cross section are small to maximize the sensitivity to dispersive effects. The analysis uses the LEDEX data from the high resolution Jefferson Lab Hall A spectrometers to extract the cross sections near the first diffraction minimum of 12C at beam energies of 362 MeV and 685 MeV. The results are in very good agreement with previous world data, although with less precision. The average deviation from a static nuclear charge distribution expected from linear and quadratic fits indicate a 30.6% contribution of dispersive effects to the cross section at 1 GeV. The magnitude of the dispersive effects near the first diffraction minimum of 12C has been confirmed to be large with a strong energy dependence and could account for a large fraction of the magnitude for the observed quenching of the longitudinal nuclear response. These effects could also be important for nuclei radii extracted from parity-violating asymmetries measured near a diffraction minimum., Comment: 14 pages, 10 figures

Published
2018
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29. Revealing Color Forces with Transverse Polarized Electron Scattering

Author

Armstrong, W., Kang, H., Liyanage, A., Maxwell, J., Mulholland, J., Ndukum, L., Ahmidouch, A., Albayrak, I., Asaturyan, A., Ates, O., Baghdasaryan, H., Boeglin, W., Bosted, P., Brash, E., Butuceanu, C., Bychkov, M., Carter, P., Chen, C., Chen, J. -P., Choi, S., Christy, M. E., Covrig, S., Crabb, D., Danagoulian, S., Daniel, A., Davidenko, A. M., Davis, B., Day, D., Deconinck, W., Deur, A., Dunne, J., Dutta, D., Fassi, L. El, Ellis, C., Ent, R., Flay, D., Frlez, E., Gaskell, D., Geagla, O., German, J., Gilman, R., Gogami, T., Gomez, J., Goncharenko, Y. M., Hashimoto, O., Higinbotham, D., Horn, T., Huber, G. M., Jones, M., Jones, M. K., Kalantarians, N., Kang, H-K., Kawama, D., Keith, C., Keppel, C., Khandaker, M., Kim, Y., King, P. M., Kohl, M., Kovacs, K., Kubarovsky, V., Li, Y., Liyanage, N., Luo, W., Mack, D., Mamyan, V., Markowitz, P., Maruta, T., Meekins, D., Melnik, Y. M., Meziani, Z. -E., Mkrtchyan, A., Mkrtchyan, H., Mochalov, V. V., Monaghan, P., Narayan, A., Nakamura, S. N., Nuruzzaman, A., Pentchev, L., Pocanic, D., Posik, M., Puckett, A., Qiu, X., Reinhold, J., Riordan, S., Roche, J., Rondón, O. A., Sawatzky, B., Shabestari, M., Slifer, K., Smith, G., Soloviev, L. F., Solvignon, P., Tadevosyan, V., Tang, L., Vasiliev, A. N., Veilleux, M., Walton, T., Wesselmann, F., Wood, S., Yao, H., Ye, Z., Zhang, J., and Zhu, L.

Subjects
Nuclear Experiment
Abstract

The Spin Asymmetries of the Nucleon Experiment (SANE) measured two double spin asymmetries using a polarized proton target and polarized electron beam at two beam energies, 4.7 GeV and 5.9 GeV. A large-acceptance open-configuration detector package identified scattered electrons at 40$^{\circ}$ and covered a wide range in Bjorken $x$ ($0.3 < x < 0.8$). Proportional to an average color Lorentz force, the twist-3 matrix element, $\tilde{d}_2^p$, was extracted from the measured asymmetries at $Q^2$ values ranging from 2.0 to 6.0 GeV$^2$. The data display the opposite sign compared to most quark models, including the lattice QCD result, and an apparently unexpected scale dependence. Furthermore when combined with the neutron data in the same $Q^2$ range the results suggest a flavor independent average color Lorentz force.

Published
2018
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30. 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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31. Measurements of Nonsinglet Moments of the Nucleon Structure Functions and Comparison to Predictions from Lattice QCD for Q2=4 GeV2

Author

Albayrak, I, Mamyan, V, Christy, ME, Ahmidouch, A, Arrington, J, Asaturyan, A, Bodek, A, Bosted, P, Bradford, R, Brash, E, Bruell, A, Butuceanu, C, Coleman, SJ, Commisso, M, Connell, SH, Dalton, MM, Danagoulian, S, Daniel, A, Day, DB, Dhamija, S, Dunne, J, Dutta, D, Ent, R, Gaskell, D, Gasparian, A, Gran, R, Horn, T, Huang, Liting, Huber, GM, Jayalath, C, Johnson, M, Jones, MK, Kalantarians, N, Liyanage, A, Keppel, CE, Kinney, E, Li, Y, Malace, S, Manly, S, Markowitz, P, Maxwell, J, Mbianda, NN, McFarland, KS, Meziane, M, Meziani, ZE, Mills, GB, Mkrtchyan, H, Mkrtchyan, A, Mulholland, J, Nelson, J, Niculescu, G, Niculescu, I, Pentchev, L, Puckett, A, Punjabi, V, Qattan, IA, Reimer, PE, Reinhold, J, Rodriguez, VM, Rondon-Aramayo, O, Sakuda, M, Sakumoto, WK, Segbefia, E, Seva, T, Sick, I, Slifer, K, Smith, GR, Steinman, J, Solvignon, P, Tadevosyan, V, Tajima, S, Tvaskis, V, Vulcan, WF, Walton, T, Wesselmann, FR, Wood, SA, and Ye, Zhihong

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, E06-009 Collaboration, nucl-ex, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract

We present extractions of the nucleon nonsinglet moments utilizing new precision data on the deuteron F_{2} structure function at large Bjorken-x determined via the Rosenbluth separation technique at Jefferson Lab Experimental Hall C. These new data are combined with a complementary set of data on the proton previously measured in Hall C at similar kinematics and world datasets on the proton and deuteron at lower x measured at SLAC and CERN. The new Jefferson Lab data provide coverage of the upper third of the x range, crucial for precision determination of the higher moments. In contrast to previous extractions, these moments have been corrected for nuclear effects in the deuteron using a new global fit to the deuteron and proton data. The obtained experimental moments represent an order of magnitude improvement in precision over previous extractions using high x data. Moreover, recent exciting developments in lattice QCD calculations provide a first ever comparison of these new experimental results with calculations of moments carried out at the physical pion mass, as well as a new approach that first calculates the quark distributions directly before determining moments.

Published
2019

32. 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, DW, Boyd, C, Gadsby, A, Gilad, S, Saha, A, Udias, JM, Goodwill, JS, 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, MM, 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, DJ, 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, PE, 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, JW, and Weinstein, LB

Subjects
nucl-ex
Abstract

Experimental cross sections for the $^4He(e,e'p)X$ reaction up to a missingmomentum 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 ImpulseApproximation(RDWIA) calculations for $^4He(e,e'p)^3H$ channel. Significantlymore 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 ofinitial-state multi-nucleon correlations are stronger than expected by theRDWIA model.

Published
2019

33. Technical supplement to “Polarization transfer observables in elastic electron-proton scattering at Q 2 = 2 . 5 , 5 . 2 , 6 . 8 and 8 . 5 GeV 2 ”

Author

Puckett, AJR, Brash, EJ, Jones, MK, Luo, W, Meziane, M, Pentchev, L, Perdrisat, CF, Punjabi, V, Wesselmann, FR, Afanasev, A, Ahmidouch, A, Albayrak, I, Aniol, KA, Arrington, J, Asaturyan, A, Baghdasaryan, H, Benmokhtar, F, Bertozzi, W, Bimbot, L, Bosted, P, Boeglin, W, Butuceanu, C, Carter, P, Chernenko, S, Christy, ME, Cornejo, JC, Covrig, S, Danagoulian, S, Daniel, A, Davidenko, A, Day, D, Dhamija, S, Dutta, D, Ent, R, Frullani, S, Fenker, H, Frlez, E, Garibaldi, F, Gaskell, D, Gilad, S, Gilman, R, Goncharenko, Y, Hafidi, K, Hamilton, D, Higinbotham, DW, Hinton, W, Horn, T, Hu, B, Huang, J, Huber, GM, Jensen, E, Keppel, C, Khandaker, M, King, P, Kirillov, D, Kohl, M, Kravtsov, V, Kumbartzki, G, Li, Y, Mamyan, V, Margaziotis, DJ, Marsh, A, Matulenko, Y, Maxwell, J, Mbianda, G, Meekins, D, Melnik, Y, Miller, J, Mkrtchyan, A, Mkrtchyan, H, Moffit, B, Moreno, O, Mulholland, J, Narayan, A, Nedev, S, Nuruzzaman, Piasetzky, E, Pierce, W, Piskunov, NM, Prok, Y, Ransome, RD, Razin, DS, Reimer, P, Reinhold, J, Rondon, O, Shabestari, M, Shahinyan, A, Shestermanov, K, Širca, S, Sitnik, I, Smykov, L, Smith, G, Solovyev, L, Solvignon, P, Subedi, R, Tomasi-Gustafsson, E, Vasiliev, A, Veilleux, M, Wojtsekhowski, BB, and Wood, S

Subjects
Nuclear and Plasma Physics, Particle and High Energy Physics, Synchrotrons and Accelerators, Physical Sciences, Proton form factors, Magnetic spectrometer, Electromagnetic calorimeter, Proton polarimeter, Polarization transfer method, Spin transport, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Other Physical Sciences, Nuclear & Particles Physics, Nuclear and plasma physics
Abstract

The GEp-III and GEp-2γ experiments, carried out in Jefferson Lab's Hall C from 2007–2008, consisted of measurements of polarization transfer in elastic electron–proton scattering at momentum transfers of Q2=2.5,5.2,6.8, and 8.54 GeV 2. These measurements were carried out to improve knowledge of the proton electromagnetic form factor ratio R=μpGEp∕GMp at large values of Q2 and to search for effects beyond the Born approximation in polarization transfer observables at Q2=2.5GeV2. The final results of both experiments were reported in a recent archival publication. A full reanalysis of the data from both experiments was carried out in order to reduce the systematic and, for the GEp-2γ experiment, statistical uncertainties. This technical note provides additional details of the final analysis omitted from the main publication, including the final evaluation of the systematic uncertainties.

Published
2018

34. Technical supplement to “Polarization transfer observables in elastic electron-proton scattering at Q2=2.5,5.2,6.8 and 8.5GeV2”

Author

Puckett, AJR, Brash, EJ, Jones, MK, Luo, W, Meziane, M, Pentchev, L, Perdrisat, CF, Punjabi, V, Wesselmann, FR, Afanasev, A, Ahmidouch, A, Albayrak, I, Aniol, KA, Arrington, J, Asaturyan, A, Baghdasaryan, H, Benmokhtar, F, Bertozzi, W, Bimbot, L, Bosted, P, Boeglin, W, Butuceanu, C, Carter, P, Chernenko, S, Christy, ME, Cornejo, JC, Covrig, S, Danagoulian, S, Daniel, A, Davidenko, A, Day, D, Dhamija, S, Dutta, D, Ent, R, Frullani, S, Fenker, H, Frlez, E, Garibaldi, F, Gaskell, D, Gilad, S, Gilman, R, Goncharenko, Y, Hafidi, K, Hamilton, D, Higinbotham, DW, Hinton, W, Horn, T, Hu, B, Huang, J, Huber, GM, Jensen, E, Keppel, C, Khandaker, M, King, P, Kirillov, D, Kohl, M, Kravtsov, V, Kumbartzki, G, Li, Y, Mamyan, V, Margaziotis, DJ, Marsh, A, Matulenko, Y, Maxwell, J, Mbianda, G, Meekins, D, Melnik, Y, Miller, J, Mkrtchyan, A, Mkrtchyan, H, Moffit, B, Moreno, O, Mulholland, J, Narayan, A, Nedev, S, Nuruzzaman, Piasetzky, E, Pierce, W, Piskunov, NM, Prok, Y, Ransome, RD, Razin, DS, Reimer, P, Reinhold, J, Rondon, O, Shabestari, M, Shahinyan, A, Shestermanov, K, Širca, S, Sitnik, I, Smykov, L, Smith, G, Solovyev, L, Solvignon, P, Subedi, R, Tomasi-Gustafsson, E, Vasiliev, A, Veilleux, M, Wojtsekhowski, BB, and Wood, S

Subjects
Proton form factors, Magnetic spectrometer, Electromagnetic calorimeter, Proton polarimeter, Polarization transfer method, Spin transport, Nuclear & Particles Physics, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Other Physical Sciences
Abstract

The GEp-III and GEp-2γ experiments, carried out in Jefferson Lab's Hall C from 2007–2008, consisted of measurements of polarization transfer in elastic electron–proton scattering at momentum transfers of Q2=2.5,5.2,6.8, and 8.54 GeV 2. These measurements were carried out to improve knowledge of the proton electromagnetic form factor ratio R=μpGEp∕GMp at large values of Q2 and to search for effects beyond the Born approximation in polarization transfer observables at Q2=2.5GeV2. The final results of both experiments were reported in a recent archival publication. A full reanalysis of the data from both experiments was carried out in order to reduce the systematic and, for the GEp-2γ experiment, statistical uncertainties. This technical note provides additional details of the final analysis omitted from the main publication, including the final evaluation of the systematic uncertainties.

Published
2018

35. Design and Performance of the Spin Asymmetries of the Nucleon Experiment

Author

Maxwell, J. D., Armstrong, W. R., Choi, S., Jones, M. K., Kang, H., Liyanage, A., Meziani, Z. -E., Mulholland, J., Ndukum, L., Rondon, O. A., Ahmidouch, A., Albayrak, I., Asaturyan, A., Ates, O., Baghdasaryan, H., Boeglin, W., Bosted, P., Brash, E., Brock, J., Butuceanu, C., Bychkov, M., Carlin, C., Carter, P., Chen, C., Chen, J. -P., Christy, M. E., Covrig, S., Crabb, D., Danagoulian, S., Daniel, A., Davidenko, A. M., Davis, B., Day, D., Deconinck, W., Deur, A., Dunne, J., Dutta, D., Fassi, L. El, Elaasar, M., Ellis, C., Ent, R., Flay, D., Frlez, E., Gaskell, D., Geagla, O., German, J., Gilman, R., Gogami, T., Gomez, J., Goncharenko, Y. M., Hashimoto, O., Higinbotham, D. W., Horn, T., Huber, G. M., Jones, M., Kalantarians, N., Kang, H. K., Kawama, D., Keith, C., Keppel, C., Khandaker, M., Kim, Y., King, P. M., Kohl, M., Kovacs, K., Kubarovsky, V., Li, Y., Liyanage, N., Luo, W., Mamyan, V., Markowitz, P., Maruta, T., Meekins, D., Melnik, Y. M., Mkrtchyan, A., Mkrtchyan, H., Mochalov, V. V., Monaghan, P., Narayan, A., Nakamura, S. N., Nuruzzaman, Pentchev, L., Pocanic, D., Posik, M., Puckett, A., Qiu, X., Reinhold, J., Riordan, S., Roche, J., Sawatzky, B., Shabestari, M., Slifer, K., Smith, G., Soloviev, L., Solvignon, P., Tadevosyan, V., Tang, L., Vasiliev, A. N., Veilleux, M., Walton, T., Wesselmann, F., Wood, S. A., Yao, H., Ye, Z., and Zhu, L.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

The Spin Asymmetries of the Nucleon Experiment (SANE) performed inclusive, double-polarized electron scattering measurements of the proton at the Continuous Electron Beam Accelerator Facility at Jefferson Lab. A novel detector array observed scattered electrons of four-momentum transfer $2.5 < Q^2< 6.5$ GeV$^2$ and Bjorken scaling $0.3

Published
2017
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36. New Results on Short-Range Correlations in Nuclei

Author

Fomin, Nadia, Higinbotham, Douglas, Sargsian, Misak, and Solvignon, Patricia

Subjects
Nuclear Theory, Nuclear Experiment
Abstract

Nuclear dynamics at short distances is one of the most fascinating topics of strong interaction physics. The physics of it is closely related to the understanding the role of the QCD in generating nuclear forces at short distances as well as understanding the dynamics of the super-dense cold nuclear matter relevant to the interior of neutron stars. With an emergence of high energy electron and proton beams there is a significant recent progress in high energy nuclear scattering experiments aimed at studies of short-range structure of nuclei. This in turn stimulated new theoretical studies resulting in the observation of several new phenomena specific to the short range structure of nuclei. In this work we review recent theoretical and experimental progress in studies of short-range correlations in nuclei and their importance for advancing our understanding of the dynamics of nuclear interactions at small distances., Comment: Review article to be published in Annual Review of Nuclear and Particle Science, 32 pages and 8 figures

Published
2017
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37. Polarization Transfer Observables in Elastic Electron Proton Scattering at $Q^2 = $2.5, 5.2, 6.8, and 8.5 GeV$^2$

Author

Puckett, A. J. R., Brash, E. J., Jones, M. K., Luo, W., Meziane, M., Pentchev, L., Perdrisat, C. F., Punjabi, V., Wesselmann, F. R., Afanasev, A., Ahmidouch, A., Albayrak, I., Aniol, K. A., Arrington, J., Asaturyan, A., Baghdasaryan, H., Benmokhtar, F., Bertozzi, W., Bimbot, L., Bosted, P., Boeglin, W., Butuceanu, C., Carter, P., Chernenko, S., Christy, E., Commisso, M., Cornejo, J. C., Covrig, S., Danagoulian, S., Daniel, A., Davidenko, A., Day, D., Dhamija, S., Dutta, D., Ent, R., Frullani, S., Fenker, H., Frlez, E., Garibaldi, F., Gaskell, D., Gilad, S., Gilman, R., Goncharenko, Y., Hafidi, K., Hamilton, D., Higinbotham, D. W., Hinton, W., Horn, T., Hu, B., Huang, J., Huber, G. M., Jensen, E., Keppel, C., Khandaker, M., King, P., Kirillov, D., Kohl, M., Kravtsov, V., Kumbartzki, G., Li, Y., Mamyan, V., Margaziotis, D. J., Marsh, A., Matulenko, Y., Maxwell, J., Mbianda, G., Meekins, D., Melnik, Y., Miller, J., Mkrtchyan, A., Mkrtchyan, H., Moffit, B., Moreno, O., Mulholland, J., Narayan, A., Nedev, S., Nuruzzaman, Piasetzky, E., Pierce, W., Piskunov, N. M., Prok, Y., Ransome, R. D., Razin, D. S., Reimer, P., Reinhold, J., Rondon, O., Shabestari, M., Shahinyan, A., Shestermanov, K., Sirca, S., Sitnik, I., Smykov, L., Smith, G., Solovyev, L., Solvignon, P., Subedi, R., Tomasi-Gustafsson, E., Vasiliev, A., Veilleux, M., Wojtsekhowski, B. B., Wood, S., Ye, Z., Zanevsky, Y., Zhang, X., Zhang, Y., Zheng, X., and Zhu, L.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

The GEp-III and GEp-2$\gamma$ experiments were carried out in Jefferson Lab's (JLab's) Hall C from 2007-2008, to extend the knowledge of $G_E^p/G_M^p$ to the highest practically achievable $Q^2$ and to search for effects beyond the Born approximation in polarization transfer observables of elastic $\vec{e}p$ scattering. This article reports an expanded description of the common experimental apparatus and data analysis procedure, and the results of a final reanalysis of the data from both experiments, including the previously unpublished results of the full-acceptance data of the GEp-2$\gamma$ experiment. The Hall C High Momentum Spectrometer detected and measured the polarization of protons recoiling elastically from collisions of JLab's polarized electron beam with a liquid hydrogen target. A large-acceptance electromagnetic calorimeter detected the elastically scattered electrons in coincidence to suppress inelastic backgrounds. The final GEp-III data are largely unchanged relative to the originally published results. The statistical uncertainties of the final GEp-2$\gamma$ data are significantly reduced at $\epsilon = 0.632$ and $0.783$ relative to the original publication. The decrease with $Q^2$ of $G_E^p/G_M^p$ continues to $Q^2 = 8.5$ GeV$^2$, but at a slowing rate relative to the approximately linear decrease observed in earlier Hall A measurements. At $Q^2 = 2.5$ GeV$^2$, the proton form factor ratio $G_E^p/G_M^p$ shows no statistically significant $\epsilon$-dependence, as expected in the Born approximation. The ratio $P_\ell/P_\ell^{Born}$ of the longitudinal polarization transfer component to its Born value shows an enhancement of roughly 1.4\% at $\epsilon = 0.783$ relative to $\epsilon = 0.149$, with $\approx 1.9\sigma$ significance based on the total uncertainty, implying a similar effect in the transverse component $P_t$ that cancels in the ratio $R$., Comment: 44 pages, 28 figures. Archival publication for the GEp-III and GEp-2gamma experiments that ran in Jefferson Lab's experimental Hall C from October, 2007 to June, 2008. v2: final manuscript as accepted by PRC. v3: Replaced figures 13 and 19 with corrected versions from published Erratum. Also made minor corrections to the text and to Table XI reflecting the corrections in the published Erratum

Published
2017
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38. Technical Supplement to 'Polarization Transfer Observables in Elastic Electron-Proton Scattering at Q$^2$ = 2.5, 5.2, 6.8, and 8.5 GeV$^2$'

Author

Puckett, A. J. R., Brash, E. J., Jones, M. K., Luo, W., Meziane, M., Pentchev, L., Perdrisat, C. F., Punjabi, V., Wesselmann, F. R., Ahmidouch, A., Albayrak, I., Aniol, K. A., Arrington, J., Asaturyan, A., Baghdasaryan, H., Benmokhtar, F., Bertozzi, W., Bimbot, L., Bosted, P., Boeglin, W., Butuceanu, C., Carter, P., Chernenko, S., Christy, E., Commisso, M., Cornejo, J. C., Covrig, S., Danagoulian, S., Daniel, A., Davidenko, A., Day, D., Dhamija, S., Dutta, D., Ent, R., Frullani, S., Fenker, H., Frlez, E., Garibaldi, F., Gaskell, D., Gilad, S., Gilman, R., Goncharenko, Y., Hafidi, K., Hamilton, D., Higinbotham, D. W., Hinton, W., Horn, T., Hu, B., Huang, J., Huber, G. M., Jensen, E., Keppel, C., Khandaker, M., King, P., Kirillov, D., Kohl, M., Kravtsov, V., Kumbartzki, G., Li, Y., Mamyan, V., Margaziotis, D. J., Marsh, A., Matulenko, Y., Maxwell, J., Mbianda, G., Meekins, D., Melnik, Y., Miller, J., Mkrtchyan, A., Mkrtchyan, H., Moffit, B., Moreno, O., Mulholland, J., Narayan, A., Nedev, S., Nurruzzaman, Piasetzky, E., Pierce, W., Piskunov, N. M., Prok, Y., Ransome, R. D., Razin, D. S., Reimer, P., Reinhold, J., Rondon, O., Shabestari, M., Shahinyan, A., Shestermanov, K., Sirca, S., Sitnik, I., Smykov, L., Smith, G., Solovyev, L., Solvignon, P., Subedi, R., Tomasi-Gustafsson, E., Vasiliev, A., Veilleux, M., Wojtsekhowski, B. B., Wood, S., Ye, Z., Zanevsky, Y., Zhang, X., Zhang, Y., Zheng, X., and Zhu, L.

Subjects
Nuclear Experiment, High Energy Physics - Experiment
Abstract

The GEp-III and GEp-2$\gamma$ experiments, carried out in Jefferson Lab's Hall C from 2007-2008, consisted of measurements of polarization transfer in elastic electron-proton scattering at momentum transfers of $Q^2 = 2.5, 5.2, 6.8,$ and $8.54$ GeV$^2$. These measurements were carried out to improve knowledge of the proton electromagnetic form factor ratio $R = \mu_p G_E^p/G_M^p$ at large values of $Q^2$ and to search for effects beyond the Born approximation in polarization transfer observables at $Q^2 = 2.5$ GeV$^2$. The final results of both experiments were reported in a recent archival publication. A full reanalysis of the data from both experiments was carried out in order to reduce the systematic and, for the GEp-2$\gamma$ experiment, statistical uncertainties. This technical note provides additional details of the final analysis omitted from the main publication, including the final evaluation of the systematic uncertainties., Comment: 33 pages, 33 figures. v3 = Final manuscript as accepted for publication in Nuclear Instruments and Methods Section A (in press)

Published
2017
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39. 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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40. 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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41. Erratum: Polarization transfer observables in elastic electron-proton scattering at Q2=2.5, 5.2, 6.8, and 8.5 GeV2 (Physical Review C (2017) 96 (055203) DOI: 10.1103/PhysRevC.96.055203)

Author

Puckett, AJR, Brash, EJ, Jones, MK, Luo, W, Meziane, M, Pentchev, L, Perdrisat, CF, Punjabi, V, Wesselmann, FR, Afanasev, A, Ahmidouch, A, Albayrak, I, Aniol, KA, Arrington, J, Asaturyan, A, Baghdasaryan, H, Benmokhtar, F, Bertozzi, W, Bimbot, L, Bosted, P, Boeglin, W, Butuceanu, C, Carter, P, Chernenko, S, Christy, ME, Commisso, M, Cornejo, JC, Covrig, S, Danagoulian, S, Daniel, A, Davidenko, A, Day, D, Dhamija, S, Dutta, D, Ent, R, Frullani, S, Fenker, H, Frlez, E, Garibaldi, F, Gaskell, D, Gilad, S, Gilman, R, Goncharenko, Y, Hafidi, K, Hamilton, D, Higinbotham, DW, Hinton, W, Horn, T, Hu, B, Huang, J, Huber, GM, Jensen, E, Keppel, C, Khandaker, M, King, P, Kirillov, D, Kohl, M, Kravtsov, V, Kumbartzki, G, Li, Y, Mamyan, V, Margaziotis, DJ, Marsh, A, Matulenko, Y, Maxwell, J, Mbianda, G, Meekins, D, Melnik, Y, Miller, J, Mkrtchyan, A, Mkrtchyan, H, Moffit, B, Moreno, O, Mulholland, J, Narayan, A, Nedev, S, Nuruzzaman, Piasetzky, E, Pierce, W, Piskunov, NM, Prok, Y, Ransome, RD, Razin, DS, Reimer, P, Reinhold, J, Rondon, O, Shabestari, M, Shahinyan, A, Shestermanov, K, Širca, S, Sitnik, I, Smykov, L, Smith, G, Solovyev, L, Solvignon, P, Subedi, R, Tomasi-Gustafsson, E, Vasiliev, A, Veilleux, M, and Wojtsekhowski, BB

Abstract

Subsequent to the release of our original paper, we discovered in the context of preparing our technical supplement [1] for journal publication that a typographical error had existed in the text file that the analysis program used to construct the beam polarization "database" for both the original analysis, published in Ref. [2], and our final analysis. The electron-beam polarization P e and the analyzing power A y cancel exactly in the ratio R , which is proportional to the ratio P t / P l of the transferred polarization components. On the other hand, the extraction of the relative e dependence of P l / P Born l relies on knowledge of the beam polarization. As such, data taking was interrupted roughly every two days during the GEp - 2 ? experiment to perform invasive measurements of the beam polarization using the Hall C Moller polarimeter [3]. The run range affected by the typographical error was entirely contained within the data collected at Q 2 = 2.5 GeV 2 with a beam energy of E e = 3.680 GeV during January 2008. The data from this configuration were combined with the data collected at E e = 3.548 GeV due to the nearly complete overlap of these two settings in terms of Q 2 and e acceptance. It is worth remarking that this typographical error went unnoticed for so long because it only affected a small fraction of the data (less than half of the combined data for ? e ? = 0.790 ) and the difference between the actually assigned beam polarization and the polarization that should have been assigned was comparable in magnitude to the point-to-point systematic uncertainty of the measurement itself. As such, its effect did not show up in various diagnostic plots and statistical tests, such as the time stability of the extracted P l / P Born l ratio. The data for both E e = 3.548 and E e = 3.680 GeV were reprocessed using the corrected beam polarizations to determine the effect of the typographical error on the combined physics results at ? e ? = 0.790 . Because the value of P e cancels in the ratio R , changes in the assumed beam polarization can only affect the results for R via statistical fluctuations due to changes in the relative weighting of different run ranges in the unbinned maximum-likelihood estimators for R . These effects are negligible on the scale of both the statistical and the systematic uncertainties of the data. More noticeable changes are expected in the ratio P l / P Born l since the extracted value of P l is inversely proportional to the assumed value of P e . Table I shows the effect of the corrected beam polarization database on the polarization transfer observables for the combined data for the ? e ? = 0.790 setting, the only measurement affected by the typographical error. The analyzing power did not need to be recalibrated since it was determined using the ? e ? = 0.153 data, which were not affected by the typographical error. As expected, the change in the ratio R is negligible. The value of P Born l , which is computed event by event from the global fit described in the Appendix of the original paper and does not depend on P e , is also unchanged. The magnitudes of P t , P l , and P l / P Born l are reduced by a common multiplicative factor, reflecting the fact that the beam polarization had been underestimated for the run range affected by the typographical error. The most important result of the corrected analysis is that the ratio P l / P Born l has decreased by 0.0024 from 1.0167 to 1.0143, a change comparable in magnitude to the statistical uncertainty but small compared to the total and point-to-point systematic uncertainties. The P l / P Born l result for the original publication [2] would be reduced by the same multiplicative factor as the final result. The physics conclusions of both publications are not materially changed by this correction. (Table Presented). (Figure Presented).

Published
2018

42. Erratum: Polarization transfer observables in elastic electron-proton scattering at Q2=2.5, 5.2, 6.8, and 8.5GeV2 [Phys. Rev. C 96, 055203 (2017)]

Author

Puckett, AJR, Brash, EJ, Jones, MK, Luo, W, Meziane, M, Pentchev, L, Perdrisat, CF, Punjabi, V, Wesselmann, FR, Afanasev, A, Ahmidouch, A, Albayrak, I, Aniol, KA, Arrington, J, Asaturyan, A, Baghdasaryan, H, Benmokhtar, F, Bertozzi, W, Bimbot, L, Bosted, P, Boeglin, W, Butuceanu, C, Carter, P, Chernenko, S, Christy, ME, Commisso, M, Cornejo, JC, Covrig, S, Danagoulian, S, Daniel, A, Davidenko, A, Day, D, Dhamija, S, Dutta, D, Ent, R, Frullani, S, Fenker, H, Frlez, E, Garibaldi, F, Gaskell, D, Gilad, S, Gilman, R, Goncharenko, Y, Hafidi, K, Hamilton, D, Higinbotham, DW, Hinton, W, Horn, T, Hu, B, Huang, J, Huber, GM, Jensen, E, Keppel, C, Khandaker, M, King, P, Kirillov, D, Kohl, M, Kravtsov, V, Kumbartzki, G, Li, Y, Mamyan, V, Margaziotis, DJ, Marsh, A, Matulenko, Y, Maxwell, J, Mbianda, G, Meekins, D, Melnik, Y, Miller, J, Mkrtchyan, A, Mkrtchyan, H, Moffit, B, Moreno, O, Mulholland, J, Narayan, A, Nedev, S, Nuruzzaman, Piasetzky, E, Pierce, W, Piskunov, NM, Prok, Y, Ransome, RD, Razin, DS, Reimer, P, Reinhold, J, Rondon, O, Shabestari, M, Shahinyan, A, Shestermanov, K, Širca, S, Sitnik, I, Smykov, L, Smith, G, Solovyev, L, Solvignon, P, Subedi, R, Tomasi-Gustafsson, E, Vasiliev, A, Veilleux, M, and Wojtsekhowski, BB

Subjects
Physical Sciences, Classical Physics, Nuclear and plasma physics
Abstract

Subsequent to the release of our original paper, we discovered in the context of preparing our technical supplement [1] for journal publication that a typographical error had existed in the text file that the analysis program used to construct the beam polarization "database" for both the original analysis, published in Ref. [2], and our final analysis. The electron-beam polarization P e and the analyzing power A y cancel exactly in the ratio R , which is proportional to the ratio P t / P l of the transferred polarization components. On the other hand, the extraction of the relative e dependence of P l / P Born l relies on knowledge of the beam polarization. As such, data taking was interrupted roughly every two days during the GEp - 2 ? experiment to perform invasive measurements of the beam polarization using the Hall C Moller polarimeter [3]. The run range affected by the typographical error was entirely contained within the data collected at Q 2 = 2.5 GeV 2 with a beam energy of E e = 3.680 GeV during January 2008. The data from this configuration were combined with the data collected at E e = 3.548 GeV due to the nearly complete overlap of these two settings in terms of Q 2 and e acceptance. It is worth remarking that this typographical error went unnoticed for so long because it only affected a small fraction of the data (less than half of the combined data for ? e ? = 0.790 ) and the difference between the actually assigned beam polarization and the polarization that should have been assigned was comparable in magnitude to the point-to-point systematic uncertainty of the measurement itself. As such, its effect did not show up in various diagnostic plots and statistical tests, such as the time stability of the extracted P l / P Born l ratio. The data for both E e = 3.548 and E e = 3.680 GeV were reprocessed using the corrected beam polarizations to determine the effect of the typographical error on the combined physics results at ? e ? = 0.790 . Because the value of P e cancels in the ratio R , changes in the assumed beam polarization can only affect the results for R via statistical fluctuations due to changes in the relative weighting of different run ranges in the unbinned maximum-likelihood estimators for R . These effects are negligible on the scale of both the statistical and the systematic uncertainties of the data. More noticeable changes are expected in the ratio P l / P Born l since the extracted value of P l is inversely proportional to the assumed value of P e . Table I shows the effect of the corrected beam polarization database on the polarization transfer observables for the combined data for the ? e ? = 0.790 setting, the only measurement affected by the typographical error. The analyzing power did not need to be recalibrated since it was determined using the ? e ? = 0.153 data, which were not affected by the typographical error. As expected, the change in the ratio R is negligible. The value of P Born l , which is computed event by event from the global fit described in the Appendix of the original paper and does not depend on P e , is also unchanged. The magnitudes of P t , P l , and P l / P Born l are reduced by a common multiplicative factor, reflecting the fact that the beam polarization had been underestimated for the run range affected by the typographical error. The most important result of the corrected analysis is that the ratio P l / P Born l has decreased by 0.0024 from 1.0167 to 1.0143, a change comparable in magnitude to the statistical uncertainty but small compared to the total and point-to-point systematic uncertainties. The P l / P Born l result for the original publication [2] would be reduced by the same multiplicative factor as the final result. The physics conclusions of both publications are not materially changed by this correction. (Table Presented). (Figure Presented).

Published
2018

43. 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, JP, Chirapatpimol, K, Cisbani, E, Dalton, MM, 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, JO, Shabestari, MH, Higinbotham, DW, 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, DJ, Markowitz, P, Meekins, D, Meziani, Z, Michaels, R, Mihovilovic, M, Muangma, N, Camacho, CM, Norum, B, Nuruzzaman, Pan, K, Phillips, S, Piasetzky, E, Pomerantz, I, Posik, M, Punjabi, V, Qian, X, Qiang, Y, Qiu, X, Reimer, PE, 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, JW, Weinstein, LB, Wojtsekhowski, B, Wood, SA, Yaron, I, Zhan, X, Zhang, J, Zhang, YW, and Zhao, B

Subjects
nucl-ex
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 He4/He3 cross section ratio is observed to be both x and Q2 independent for 1.52, our data support the hypothesis that a previous claim of three-nucleon correlation dominance was an artifact caused by the limited resolution of the measurement. While 3N-SRCs appear to have an important contribution, our data show that isolating 3N-SRCs is significantly more complicated than for 2N-SRCs.

Published
2018

44. JLab Measurements of the 3He Form Factors at Large Momentum Transfers

Author

Camsonne, A., Katramatou, A. T., Olson, M., Acha, A., Allada, K., Anderson, B. D., Arrington, J., Baldwin, A., Chen, J. -P., Choi, S., Chudakov, E., Cisbani, E., Craver, B., Decowski, P., Dutta, C., Folts, E., Frullani, S., Garibaldi, F., Gilman, R., Gomez, J., Hahn, B., Hansen, J. -O., Higinbotham, D. W., Holmstrom, T., Huang, J., Iodice, M., Jiang, X., Kelleher, A., Khrosinkova, E., Kievsky, A., Kuchina, E., Kumbartzki, G., Lee, B., LeRose, J. J., Lindgren, R. A., Lott, G., Lu, H., Marcucci, L. E., Margaziotis, D. J., Markowitz, P., Marrone, S., Meekins, D., Meziani, Z. -E., Michaels, R., Moffit, B., Norum, B., Petratos, G. G., Puckett, A., Qian, X., Rondon, O., Saha, A., Sawatzky, B., Segal, J., Shabestari, M., Shahinyan, A., Solvignon, P., Sparveris, N., Subedi, R. R., Suleiman, R., Sulkosky, V., Urciuoli, G. M., Viviani, M., Wang, Y., Wojtsekhowski, B. B., Yan, X., Yao, H., Zhang, W. -M., Zheng, X., and Zhu, L.

Subjects
Nuclear Experiment
Abstract

The charge and magnetic form factors, FC and FM, of 3He have been extracted in the kinematic range 25 fm-2 < Q2 < 61 fm-2 from elastic electron scattering by detecting 3He recoil nuclei and electrons in coincidence with the High Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The measurements are indicative of a second diffraction minimum for the magnetic form factor, which was predicted in the Q2 range of this experiment, and of a continuing diffractive structure for the charge form factor. The data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the three-body nuclear problem.

Published
2016
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45. A novel comparison of M{\o}ller and Compton electron-beam polarimeters

Author

Magee, J. A., Narayan, A., Jones, D., Beminiwattha, R., Cornejo, J. C., Dalton, M. M., Deconinck, W., Dutta, D., Gaskell, D., Martin, J. W., Paschke, K. D., Tvaskis, V., Asaturyan, A., Benesch, J., Cates, G., Cavness, B. S., Dillon-Townes, L. A., Hays, G., Hoskins, J., Ihloff, E., Jones, R., King, P. M., Kowalski, S., Kurchaninov, L., Lee, L., McCreary, A., McDonald, M., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Nelyubin, V., Page, S., Ramsay, W. D., Solvignon, P., Storey, D., Tobias, W. A., Urban, E., Vidal, C., Waidyawansa, B., Wang, P., and Zhamkotchyan, S.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

We have performed a novel comparison between electron-beam polarimeters based on M{\o}ller and Compton scattering. A sequence of electron-beam polarization measurements were performed at low beam currents ($<$ 5 $\mu$A) during the $Q_{\rm weak}$ experiment in Hall C at Jefferson Lab. These low current measurements were bracketed by the regular high current (180 $\mu$A) operation of the Compton polarimeter. All measurements were found to be consistent within experimental uncertainties of 1% or less, demonstrating that electron polarization does not depend significantly on the beam current. This result lends confidence to the common practice of applying M{\o}ller measurements made at low beam currents to physics experiments performed at higher beam currents. The agreement between two polarimetry techniques based on independent physical processes sets an important benchmark for future precision asymmetry measurements that require sub-1% precision in polarimetry.

Published
2016
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46. 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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47. Measurements of $d_{2}^{n}$ and $A_{1}^{n}$: Probing the neutron spin structure

Author

Flay, D., Posik, M., Parno, D. S., Allada, K., Armstrong, W., Averett, T., Benmokhtar, F., Bertozzi, W., Camsonne, A., Canan, M., Cates, G. D., Chen, C., Chen, J. -P., Choi, S., Chudakov, E., Cusanno, F., Dalton, M. M., Deconinck, W., de Jager, C. W., Deng, X., Deur, A., Dutta, C., Fassi, L. El, Franklin, G. B., Friend, M., Gao, H., Garibaldi, F., Gilad, S., Gilman, R., Glamazdin, O., Golge, S., Gomez, J., Guo, L., Hansen, O., Higinbotham, D. W., Holmstrom, T., Huang, J., Hyde, C., Ibrahim, H. F., Jiang, X., Jin, G., Katich, J., Kelleher, A., Kolarkar, A., Korsch, W., Kumbartzki, G., LeRose, J. J., Lindgren, R., Liyanage, N., Long, E., Lukhanin, A., Mamyan, V., McNulty, D., Meziani, Z. -E., Michaels, R., Mihovilovič, M., Moffit, B., Muangma, N., Nanda, S., Narayan, A., Nelyubin, V., Norum, B., Oh, Y., Peng, J. C., Qian, X., Qiang, Y., Rakhman, A., Riordan, S., Saha, A., Sawatzky, B., Shabestari, M. H., Shahinyan, A., Širca, S., Solvignon, P., Subedi, R., Sulkosky, V., Tobias, A., Troth, W., Wang, D., Wang, Y., Wojtsekhowski, B., Yan, X., Yao, H., Ye, Y., Ye, Z., Yuan, L., Zhan, X., Zhang, Y., Zhang, Y. -W., Zhao, B., and Zheng, X.

Subjects
Nuclear Experiment, Nuclear Theory
Abstract

We report on the results of the E06-014 experiment performed at Jefferson Lab in Hall A, where a precision measurement of the twist-3 matrix element $d_2$ of the neutron ($d_{2}^{n}$) was conducted. This quantity represents the average color Lorentz force a struck quark experiences in a deep inelastic electron scattering event off a neutron due to its interaction with the hadronizing remnants. This color force was determined from a linear combination of the third moments of the spin structure functions $g_1$ and $g_2$ on $^{3}$He after nuclear corrections had been applied to these moments. The kinematics included two average $Q^{2}$ bins of $3.2$ GeV$^{2}$ and $4.3$ GeV$^{2}$, and Bjorken-$x$ $0.25 \leq x \leq 0.90$ covering the DIS and resonance regions. We found $d_2^n$ to be small and negative for $ = 3.2$ GeV$^{2}$, and smaller for $ = 4.3$ GeV$^{2}$, consistent with a lattice QCD calculation. The twist-4 matrix element $f_{2}^{n}$ was extracted by combining our $d_{2}^{n}$ with the world data on $\Gamma_{1}^{n} = \int_{0}^{1} g_{1}^{n} dx$. We found $f_{2}^{n}$ to be roughly an order of magnitude larger than $d_{2}^{n}$. Utilizing the extracted $d_{2}^{n}$ and $f_{2}^{n}$ data, we separated the color force into its electric and magnetic components, $F_{E}^{y,n}$ and $F_{B}^{y,n}$, and found them to be equal and opposite in magnitude, in agreement with instanton model predictions but not with those from QCD sum rules. Additionally, we have extracted the neutron virtual photon-nucleon asymmetry $A_{1}^{n}$, the structure function ratio $g_{1}^{n}/F_{1}^{n}$, and the quark ratios $(\Delta u + \Delta \bar{u})/(u + \bar{u})$ and $(\Delta d + \Delta \bar{d})/(d + \bar{d})$. These results were found to be consistent with DIS world data and with the prediction of the constituent quark model but at odds with those of perturbative QCD at large $x$., Comment: 55 Pages, 45 figures, 48 tables. 15 supplemental files. Grammatical and typo fixes. Revised some model descriptions and updated analyses for f_2^n and color forces

Published
2016
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48. Publisher’s Note: JLab Measurements of the He3 Form Factors at Large Momentum Transfers [Phys. Rev. Lett. 119, 162501 (2017)]

Author

Camsonne, A, Katramatou, AT, Olson, M, Acha, A, Allada, K, Anderson, BD, Arrington, J, Baldwin, A, Chen, J-P, Choi, S, Chudakov, E, Cisbani, E, Craver, B, Decowski, P, Dutta, C, Folts, E, Frullani, S, Garibaldi, F, Gilman, R, Gomez, J, Hahn, B, Hansen, J-O, Higinbotham, DW, Holmstrom, T, Huang, J, Iodice, M, Jiang, X, Kelleher, A, Khrosinkova, E, Kievsky, A, Kuchina, E, Kumbartzki, G, Lee, B, LeRose, JJ, Lindgren, RA, Lott, G, Lu, H, Marcucci, LE, Margaziotis, DJ, Markowitz, P, Marrone, S, Meekins, D, Meziani, Z-E, Michaels, R, Moffit, B, Norum, B, Petratos, GG, Puckett, A, Qian, X, Rondon, O, Saha, A, Sawatzky, B, Segal, J, Shabestari, M, Shahinyan, A, Solvignon, P, Sparveris, N, Subedi, RR, Suleiman, R, Sulkosky, V, Urciuoli, GM, Viviani, M, Wang, Y, Wojtsekhowski, BB, Yan, X, Yao, H, Zhang, W-M, Zheng, X, and Zhu, L

Subjects
Quantum Physics, Physical Sciences, Jefferson Lab Hall A Collaboration, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract

This corrects the article DOI: 10.1103/PhysRevLett.119.162501.

Published
2017

49. Publisher's Note: JLab Measurements of the ^{3}He Form Factors at Large Momentum Transfers [Phys. Rev. Lett. 119, 162501 (2017)].

Author

Camsonne, A, Katramatou, AT, Olson, M, Acha, A, Allada, K, Anderson, BD, Arrington, J, Baldwin, A, Chen, J-P, Choi, S, Chudakov, E, Cisbani, E, Craver, B, Decowski, P, Dutta, C, Folts, E, Frullani, S, Garibaldi, F, Gilman, R, Gomez, J, Hahn, B, Hansen, J-O, Higinbotham, DW, Holmstrom, T, Huang, J, Iodice, M, Jiang, X, Kelleher, A, Khrosinkova, E, Kievsky, A, Kuchina, E, Kumbartzki, G, Lee, B, LeRose, JJ, Lindgren, RA, Lott, G, Lu, H, Marcucci, LE, Margaziotis, DJ, Markowitz, P, Marrone, S, Meekins, D, Meziani, Z-E, Michaels, R, Moffit, B, Norum, B, Petratos, GG, Puckett, A, Qian, X, Rondon, O, Saha, A, Sawatzky, B, Segal, J, Shabestari, M, Shahinyan, A, Solvignon, P, Sparveris, N, Subedi, RR, Suleiman, R, Sulkosky, V, Urciuoli, GM, Viviani, M, Wang, Y, Wojtsekhowski, BB, Yan, X, Yao, H, Zhang, W-M, Zheng, X, Zhu, L, and Jefferson Lab Hall A Collaboration

Subjects
Jefferson Lab Hall A Collaboration, General Physics, Mathematical Sciences, Physical Sciences, Engineering
Abstract

This corrects the article DOI: 10.1103/PhysRevLett.119.162501.

Published
2017

50. Polarization transfer observables in elastic electron-proton scattering at Q2=2.5, 5.2, 6.8, and 8.5 GeV2 POLARIZATION TRANSFER OBSERVABLES in ELASTIC ... A. J. R. PUCKETT et al.

Author

Puckett, AJR, Brash, EJ, Jones, MK, Luo, W, Meziane, M, Pentchev, L, Perdrisat, CF, Punjabi, V, Wesselmann, FR, Afanasev, A, Ahmidouch, A, Albayrak, I, Aniol, KA, Arrington, J, Asaturyan, A, Baghdasaryan, H, Benmokhtar, F, Bertozzi, W, Bimbot, L, Bosted, P, Boeglin, W, Butuceanu, C, Carter, P, Chernenko, S, Christy, ME, Commisso, M, Cornejo, JC, Covrig, S, Danagoulian, S, Daniel, A, Davidenko, A, Day, D, Dhamija, S, Dutta, D, Ent, R, Frullani, S, Fenker, H, Frlez, E, Garibaldi, F, Gaskell, D, Gilad, S, Gilman, R, Goncharenko, Y, Hafidi, K, Hamilton, D, Higinbotham, DW, Hinton, W, Horn, T, Hu, B, Huang, J, Huber, GM, Jensen, E, Keppel, C, Khandaker, M, King, P, Kirillov, D, Kohl, M, Kravtsov, V, Kumbartzki, G, Li, Y, Mamyan, V, Margaziotis, DJ, Marsh, A, Matulenko, Y, Maxwell, J, Mbianda, G, Meekins, D, Melnik, Y, Miller, J, Mkrtchyan, A, Mkrtchyan, H, Moffit, B, Moreno, O, Mulholland, J, Narayan, A, Nedev, S, Nuruzzaman, Piasetzky, E, Pierce, W, Piskunov, NM, Prok, Y, Ransome, RD, Razin, DS, Reimer, P, Reinhold, J, Rondon, O, Shabestari, M, Shahinyan, A, Shestermanov, K, Širca, S, Sitnik, I, Smykov, L, Smith, G, Solovyev, L, Solvignon, P, Subedi, R, Tomasi-Gustafsson, E, Vasiliev, A, Veilleux, M, and Wojtsekhowski, BB

Abstract

Background: Interest in the behavior of nucleon electromagnetic form factors at large momentum transfers has steadily increased since the discovery, using polarization observables, of the rapid decrease of the ratio GEp/GMp of the proton's electric and magnetic form factors for momentum transfers Q21 GeV2, in strong disagreement with previous extractions of this ratio using the traditional Rosenbluth separation technique. Purpose: The GEp-III and GEp-2γ experiments were carried out in Jefferson Laboratory's (JLab's) Hall C from 2007 to 2008, to extend the knowledge of GEp/GMp to the highest practically achievable Q2 given the maximum beam energy of 6 GeV and to search for effects beyond the Born approximation in polarization transfer observables of elastic ∫ - p scattering. This article provides an expanded description of the common experimental apparatus and data analysis procedures, and reports the results of a final reanalysis of the data from both experiments, including the previously unpublished results of the full-acceptance dataset of the GEp-2γ experiment. Methods: Polarization transfer observables in elastic ∫ - p→∫ - scattering were measured at central Q2 values of 2.5, 5.2, 6.8, and 8.54 GeV2. At Q2=2.5GeV2, data were obtained for central values of the virtual photon polarization parameter ϵ of 0.149, 0.632, and 0.783. The Hall C High Momentum Spectrometer detected and measured the polarization of protons recoiling elastically from collisions of JLab's polarized electron beam with a liquid hydrogen target. A large-acceptance electromagnetic calorimeter detected the elastically scattered electrons in coincidence to suppress inelastic backgrounds. Results: The final GEp-III data are largely unchanged relative to the originally published results. The statistical uncertainties of the final GEp-2γ data are significantly reduced at ϵ=0.632 and 0.783 relative to the original publication. Conclusions: The final GEp-III results show that the decrease with Q2 of GEp/GMp continues to Q2=8.5GeV2, but at a slowing rate relative to the approximately linear decrease observed in earlier Hall A measurements. At Q2=8.5GeV2, GEp/GMp remains positive but is consistent with zero. At Q2=2.5GeV2, GEp/GMp derived from the polarization component ratio R-Pt/P shows no statistically significant ϵ dependence, as expected in the Born approximation. On the other hand, the ratio P""/P""Born of the longitudinal polarization transfer component to its Born value shows an enhancement of roughly 1.7% at ϵ=0.783 relative to ϵ=0.149, with ≈2.2σ significance based on the total uncertainty, implying a similar effect in the transverse component Pt that cancels in the ratio R.

Published
2017

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