Author: "Mammei, J." - Searchworks@Jio Institute Digital Library Search Results

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179 results on '"Mammei, J."'

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

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

4. Ultra-High precision Compton polarimetry at 2 GeV

Author: Zec, A., Premathilake, S., Cornejo, J. C., Dalton, M. M., Gal, C., Gaskell, D., Gericke, M., Halilovic, I., Liu, H., Mammei, J., Michaels, R., Palatchi, C., Pan, J., Paschke, K. D., Quinn, B., and Zhang, J.
Subjects: Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract: We report a high precision measurement of electron beam polarization using Compton polarimetry. The measurement was made in experimental Hall A at Jefferson Lab during the CREX experiment in 2020. A total uncertainty of dP/P=0.36% was achieved detecting the back-scattered photons from the Compton scattering process. This is the highest accuracy in a measurement of electron beam polarization using Compton scattering ever reported, surpassing the ground-breaking measurement from the SLAC Large Detector (SLD) Compton polarimeter. Such uncertainty reaches the level required for the future flagship measurements to be made by the MOLLER and SoLID experiments.
Published: 2024
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5. 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

6. ATHENA Detector Proposal -- A Totally Hermetic Electron Nucleus Apparatus proposed for IP6 at the Electron-Ion Collider

Author: ATHENA Collaboration, Adam, J., Adamczyk, L., Agrawal, N., Aidala, C., Akers, W., Alekseev, M., Allen, M. M., Ameli, F., Angerami, A., Antonioli, P., Apadula, N. J., Aprahamian, A., Armstrong, W., Arratia, M., Arrington, J. R., Asaturyan, A., Aschenauer, E. C., Augsten, K., Aune, S., Bailey, K., Baldanza, C., Bansal, M., Barbosa, F., Barion, L., Barish, K., Battaglieri, M., Bazilevsky, A., Behera, N. K., Berdnikov, V., Bernauer, J., Berriaud, C., Bhasin, A., Bhattacharya, D. S., Bielcik, J., Bielcikova, J., Bissolotti, C., Boeglin, W., Bondì, M., Borri, M., Bossu, F., Bouyjou, F., Brandenburg, J. D., Bressan, A., Brooks, M., Bueltmann, S. L., Byer, D., Caines, H., Sanchez, M. Calderon de la Barca, Calvelli, V., Camsonne, A., Cappelli, L., Capua, M., Castro, M., Cavazza, D., Cebra, D., Celentano, A., Chakaberia, I., Chan, B., Chang, W., Chartier, M., Chatterjee, C., Chen, D., Chen, J., Chen, K., Chen, Z., Chetri, H., Chiarusi, T., Chiosso, M., Chu, X., Chwastowski, J. J., Cicala, G., Cisbani, E., Cline, E., Cloet, I., Colella, D., Contalbrigo, M., Contin, G., Corliss, R., Corrales-Morales, Y., Crafts, J., Crawford, C., Cruz-Torres, R., D'Ago, D., D'Angelo, A., D'Hose, N., Dainton, J., Torre, S. Dalla, Dasgupta, S. S., Dash, S., Dashyan, N., Datta, J., Daugherity, M., De Vita, R., Deconinck, W., Defurne, M., Dehmelt, K., Del Dotto, A., Delcarro, F., Dellacasa, G., Demiroglu, Z. S., Deptuch, G. W., Desai, V., Deshpande, A., Devereaux, K., Dhillon, R., Di Salvo, R., Dilks, C., Dixit, D., Dobbs, S., Dong, X., Drachenberg, J., Drees, A., Dupre, R., Durham, M., Dzhygadlo, R., Fassi, L. El, Elia, D., Epple, E., Esha, R., Evdokimov, O., Eyser, O., Falchieri, D., Fan, W., Fantini, A., Fatemi, R., Fazio, S., Fegan, S., Filippi, A., Fox, H., Francisco, A., Freeze, A., Furletov, S., Furletova, Y., Gal, C., Gardner, S., Garg, P., Gaskell, D., Gates, K., Gericke, M. T. W., Geurts, F., Ghosh, C., Giacalone, M., Giacomini, F., Gilchrist, S., Glazier, D., Gnanvo, K., Gonella, L., Greiner, L. C., Guerrini, N., Guo, L., Gupta, A., Gupta, R., Guryn, W., He, X., Hemmick, T., Heppelmann, S., Higinbotham, D., Hoballah, M., Hoghmrtsyan, A., Hohlmann, M., Horn, T., Hornidge, D., Huang, H. Z., Hyde, C. E., Iapozzuto, P., Idzik, M., Jacak, B. V., Jadhav, M., Jain, S., Jena, C., Jentsch, A., Ji, Y., Ji, Z., Jia, J., Jones, P. G., Jones, R. W. I., Joosten, S., Joshi, S., Kabir, L., Kalicy, G., Karyan, G., Kashyap, V. K. S., Kawall, D., Ke, H., Kelsey, M., Kim, J., Kiryluk, J., Kiselev, A., Klein, S. R., Klest, H., Kochar, V., Korsch, W., Kosarzewski, L., Kotzinian, A., Krizek, F., Kumar, A., Kumar, K. S., Kumar, L., Kumar, R., Kumar, S., Kunnath, A., Kushawaha, N., Lacey, R., Lai, Y. S., Lalwani, K., Landgraf, J., Lanza, L., Lattuada, D., Lavinsky, M., Lee, J. H., Lee, S. H., Lemmon, R., Lestone, A., Lewis, N., Li, H., Li, S., Li, W., Li, X., Liang, X., Ligonzo, T., Lin, T., Liu, J., Liu, K., Liu, M., Livingston, K., Liyanage, N., Ljubicic, T., Long, O., Lukow, N., Ma, Y., Mammei, J., Mammoliti, F., Mamo, K., Mandjavidze, I., Maple, S., Marchand, D., Margotti, A., Markert, C., Markowitz, P., Marshall, T., Martin, A., Marukyan, H., Mastroserio, A., Mathew, S., Mayilyan, S., Mayri, C., McEneaney, M., Mei, Y., Meng, L., Meot, F., Metcalfe, J., Meziani, Z. -E., Mihir, P., Milton, R., Mirabella, A., Mirazita, M., Mkrtchyan, A., Mkrtchyan, H., Mohanty, B., Mondal, M., Morreale, A., Movsisyan, A., Muenstermann, D., Mukherjee, A., Camacho, C. Munoz, Murray, M. J., Mustafa, H., Myska, M., Nachman, B. P., Nagai, K., Naik, R., Naim, J. P., Nam, J., Nandi, B., Nappi, E., Nasim, Md., Neff, D., Neiret, D., Newman, P. R., Nguyen, M., Niccolai, S., Nie, M., Noferini, F., Norman, J., Noto, F., Nunes, A. S., O'Connor, T., Odyniec, G., Okorokov, V. A., Osipenko, M., Page, B., Palatchi, C., Palmer, D., Palni, P., Pandey, S., Panzieri, D., Park, S., Paschke, K., Pastore, C., Patra, R. N., Paul, A., Paul, S., Pecar, C., Peck, A., Pegg, I., Pellegrino, C., Peng, C., Pentchev, L., Perrino, R., Piotrzkowski, K., Polakovic, T., Ploskon, M., Posik, M., Prasad, S., Preghenella, R., Priens, S., Prifti, E., Przybycien, M., Pujahari, P., Quintero, A., Radici, M., Radhakrishnan, S. K., Rahman, S., Rathi, S., Raue, B., Reed, R., Reimer, P., Reinhold, J., Renner, E., Rignanese, L., Ripani, M., Rizzo, A., Romanov, D., Roy, A., Rubini, N., Ruspa, M., Ruan, L., Sabatie, F., Sadhukhan, S., Sahoo, N., Sahu, P., Samuel, D., Sarkar, A., Sarsour, M., Schmidke, W., Schmookler, B., Schwarz, C., Schwiening, J., Scott, M., Sedgwick, I., Segreti, M., Sekula, S., Seto, R., Shah, N., Shahinyan, A., Sharma, D., Sharma, N., Sichtermann, E. P., Signori, A., Singh, A., Singh, B. K., Singh, S. N., Smirnov, N., Sokhan, D., Soltz, R., Sondheim, W., Spinali, S., Stacchi, F., Staszewski, R., Stepanov, P., Strazzi, S., Stroe, I. R., Sun, X., Surrow, B., Sweger, Z., Symons, T. J., Tadevosyan, V., Tang, A., Tassi, E., Teodorescu, L., Tessarotto, F., Thomas, D., Thomas, J. H., Toll, T., Tomasek, L., Torales-Acosta, F., Tribedy, P., Triloki, Tripathi, V., Trotta, R., Trzebiński, M., Trzeciak, B. A., Tsai, O., Tu, Z., Turrisi, R., Tuve, C., Ullrich, T., Urciuoli, G. M., Valentini, A., Vallarino, S., Vandenbroucke, M., Vanek, J., Vino, G., Volpe, G., Voskanyan, H., Vossen, A., Voutier, E., Wang, G., Wang, Y., Watts, D., Wickramaarachchi, N., Wilson, F., Wong, C. -P., Wu, X., Wu, Y., Xie, J., Xu, Q. -H., Xu, Z., Xu, Z. W., Yang, C., Yang, Q., Yang, Y., Ye, Z., Yi, L., Yin, Z., Yurov, M., Zachariou, N., Zhang, J., Zhang, Y., Zhang, Z., Zhao, Y., Zhao, Y. X., Zhao, Z., Zheng, L., and Zurek, M.
Subjects: Physics - Instrumentation and Detectors, High Energy Physics - Experiment, Nuclear Experiment
Abstract: ATHENA has been designed as a general purpose detector capable of delivering the full scientific scope of the Electron-Ion Collider. Careful technology choices provide fine tracking and momentum resolution, high performance electromagnetic and hadronic calorimetry, hadron identification over a wide kinematic range, and near-complete hermeticity. This article describes the detector design and its expected performance in the most relevant physics channels. It includes an evaluation of detector technology choices, the technical challenges to realizing the detector and the R&D required to meet those challenges.
Published: 2022

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

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

Author: Akatsuka, H., Andalib, T., Bell, B., Berean-Dutcher, J., Bernier, N., Bidinosti, C. P., Cude-Woods, C., Currie, S. A., Davis, C. A., Franke, B., Gaur, R., Giampa, P., Hansen-Romu, S., Hassan, M. T., Hatanaka, K., Higuchi, T., Gibson, C., Ichikawa, G., Ide, I., Imajo, S., Ito, T. M., Jamieson, B., Kawasaki, S., Kitaguchi, M., Klassen, W., Korkmaz, E., Kuchler, F., Lang, M., Lavvaf, M., Lindner, T., Makela, M., Mammei, J., Mammei, R., Martin, J. W., Matsumiya, R., Miller, E., Mishima, K., Momose, T., Morawetz, S., Morris, C. L., Ong, H. J., O'Shaughnessy, C. M., Pereira-Wilson, M., Picker, R., Piermaier, F., Pierre, E., Schreyer, W., Sidhu, S., Stang, D., Tiepo, V., Vanbergen, S., Wang, R., Wong, D., and Yamamoto, N.
Subjects: Nuclear Experiment
Abstract: Electroless nickel plating is an established industrial process that provides a robust and relatively low-cost coating suitable for transporting and storing ultracold neutrons (UCN). Using roughness measurements and UCN-storage experiments we characterized UCN guides made from polished aluminum or stainless-steel tubes plated by several vendors. All electroless nickel platings were similarly suited for UCN storage with an average loss probability per wall bounce of $2.8\cdot10^{-4}$ to $4.1\cdot10^{-4}$ for energies between 90 neV and 190 neV, or a ratio of imaginary to real Fermi potential $\eta$ of $1.7\cdot10^{-4}$ to $3.3\cdot10^{-4}$. Measurements at different elevations indicate that the energy dependence of UCN losses is well described by the imaginary Fermi potential. Some special considerations are required to avoid an increase in surface roughness during the plating process and hence a reduction in UCN transmission. Increased roughness had only a minor impact on storage properties. Based on these findings we chose a vendor to plate the UCN-production vessel that will contain the superfluid-helium converter for the new TRIUMF UltraCold Advanced Neutron (TUCAN) source, achieving acceptable UCN-storage properties with ${\eta=3.5(5)\cdot10^{-4}}$., Comment: 8 pages, 7 figures
Published: 2022
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9. Snowmass 2021 White Paper on Upgrading SuperKEKB with a Polarized Electron Beam: Discovery Potential and Proposed Implementation

Author: Accardi, A., Asner, D. M., Atmacan, H., Baartman, R., Banerjee, Sw., Beaubien, A., Bennett, J. V., Bertemes, M., Bessner, M., Biswas, D., Bonvicini, G., Brenny, N., Briere, R. A., Browder, T. E., Chen, C., Choudhury, S., Cinabro, D., Cochran, J., Cremaldi, L. M., Deconinck, W., Di Canto, A., Dubey, S., Flood, K., Fulsom, B. G., Gaur, V., Gericke, M., Godang, R., Gu, T., Guan, Y., Guilliams, J., Hadjivasiliou, C., Hartbrich, O., Hearty, C., Hoferichter, M., Jacobs, W. W., Jaffe, D. E., Junginger, T., Kang, S., Kapitánová, L., Ketter, C., Khatri, A., Kinoshita, K., Kohani, S., Koop, I. A., Korandla, H., Sari, I. Koseoglu, Kroeger, R., Kumar, J., Kumara, K. J., Kuriki, M., Lam, T., Laycock, P. J., Diberder, F. R. Le, Li, L., Liptak, Z., Liventsev, D., Mammei, J., Martens, A., Meier, F., Miller, C., Mitra, S., Moorthy, K., Natochii, A., Nellikunnummel, N., Nishimura, K. A., Otboev, A. V., Oxford, E. R., Panta, A., Parham, K., Parker, B., Pedlar, T. K., Peng, Y., Peschke, R., Piilonen, L. E., Planche, T., Pokharel, S., Prell, S., Purwar, H., Herrmann, D. E. Ricalde, Roney, J. M., Rosenfeld, C., Sahoo, D., Sanders, D. A., Sangal, A., Savinov, V., Schneider, S., Schueler, J., Schwartz, A. J., Shatunov, Yu. M., Shebalin, V., Sibidanov, A., Signori, A., Stottler, Z. S., Strube, J., Trabelsi, K., Tripathi, S., Vahsen, S. E., Varner, G. S., Vossen, A., Wang, D., Wang, E., Wienands, U., Wood, L., Yelton, J., Zhai, Y., Zhang, B., Zhou, D., and Zomer, F.
Subjects: Physics - Accelerator Physics, High Energy Physics - Experiment
Abstract: Upgrading the SuperKEKB electron-positron collider with polarized electron beams opens a new program of precision physics at a center-of-mass energy of 10.58 GeV. This white paper describes the physics potential of this `Chiral Belle' program. It includes projections for precision measurements of $\sin^2\theta_W$ that can be obtained from independent left-right asymmetry measurements of $e^+e^-$ transitions to pairs of electrons, muons, taus, charm and b-quarks. The $\sin^2\theta_W$ precision obtainable at SuperKEKB will match that of the LEP/SLC world average, but at the centre-of-mass energy of 10.58 GeV. Measurements of the couplings for muons, charm, and $b$-quarks will be substantially improved and the existing $3\sigma$ discrepancy between the SLC $A_{LR}$ and LEP $A_{FB}^b$ measurements will be addressed. Precision measurements of neutral current universality will be more than an order of magnitude more precise than currently available. As the energy scale is well away from the $Z^0$-pole, the precision measurements will have sensitivity to the presence of a parity-violating dark sector gauge boson, $Z_{\rm dark}$. The program also enables the measurement of the anomalous magnetic moment $g-2$ form factor of the $\tau$ to be made at an unprecedented level of precision. A precision of $10^{-5}$ level is accessible with 40~ab$^{-1}$ and with more data it would start to approach the $10^{-6}$ level. This technique would provide the most precise information from the third generation about potential new physics explanations of the muon $g-2$ $4\sigma$ anomaly. Additional $\tau$ and QCD physics programs enabled or enhanced with having polarized electron beams are also discussed in this White Paper. This paper includes a summary of the path forward in R&D and next steps required to implement this upgrade and access its exciting discovery potential., Comment: 74 pages, 56 figures, contribution to Snowmass 2021
Published: 2022

10. Precision Determination of the Neutral Weak Form Factor of $^{48}$Ca

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

Author: Georges, F., Rashad, M. N. H., Stefanko, A., Dlamini, M., Karki, B., Ali, S. F., Lin, P-J., Ko, H-S, Israel, N., Adikaram, D., Ahmed, Z., Albataineh, H., Aljawrneh, B., Allada, K., Allison, S., Alsalmi, S., Androic, D., Aniol, K., Annand, J., Atac, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Bane, J., Barcus, S., Bartlett, K., Bellini, V., Beminiwattha, R., Bericic, J., Biswas, D., Brash, E., Bulumulla, D., Campbell, J., Camsonne, A., Carmignotto, M., Castellano, J., Chen, C., Chen, J-P., Chetry, T., Christy, M. E., Cisbani, E., Clary, B., Cohen, E., Compton, N., Cornejo, J. C., Dusa, S. Covrig, Crowe, B., Danagoulian, S., Danley, T., De Persio, F., Deconinck, W., Defurne, M., Desnault, C., Di, D., Duer, M., Duran, B., Ent, R., Fanelli, C., Franklin, G., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Glamazdin, O., Gnanvo, K., Gray, V. M., Gu, C., Hague, T., Hamad, G., Hamilton, D., Hamilton, K., Hansen, O., Hauenstein, F., Henry, W., Higinbotham, D. W., Holmstrom, T., Horn, T., Huang, Y., Huber, G. M., Hyde, C., Ibrahim, H., Jen, C-M., Jin, K., Jones, M., Kabir, A., Keppel, C., Khachatryan, V., King, P. M., Li, S., Li, W. B., Liu, J., Liu, H., Liyanage, A., Magee, J., Malace, S., Mammei, J., Markowitz, P., McClellan, E., Mazouz, M., Meddi, F., Meekins, D., Mesik, K., Michaels, R., Mkrtchyan, A., Montgomery, R., Camacho, C. Muñoz, Myers, L. S., Nadel-Turonski, P., Nazeer, S. J., Nelyubin, V., Nguyen, D., Nuruzzaman, N., Nycz, M., Obretch, O. F., Ou, L., Palatchi, C., Pandey, B., Park, S., Park, K., Peng, C., Pomatsalyuk, R., Pooser, E., Puckett, A. J. R., Punjabi, V., Quinn, B., Rahman, S., Reimer, P. E., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N. H., Schmookler, B., Shabestari, M. H., Shahinyan, A., Sirca, S., Smith, G. R., Sooriyaarachchilage, S., Sparveris, N., Spies, R., Su, T., Subedi, A., Sulkosky, V., Sun, A., Thorne, L., Tian, Y., Ton, N., Tortorici, F., Trotta, R., Urciuoli, G. M., Voutier, E., Waidyawansa, B., Wang, Y., Wojtsekhowski, B., Wood, S., Yan, X., Ye, L., Ye, Z., Yero, C., Zhang, J., Zhao, Y., and Zhu, P.
Subjects: High Energy Physics - Phenomenology, High Energy Physics - Experiment, Nuclear Experiment
Abstract: We report high-precision measurements of the Deeply Virtual Compton Scattering (DVCS) cross section at high values of the Bjorken variable $x_B$. DVCS is sensitive to the Generalized Parton Distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton Form Factors (CFFs) of the nucleon as a function of $x_B$, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.
Published: 2022
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12. 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

13. 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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14. New Measurements of the Beam-Normal Single Spin Asymmetry in Elastic Electron Scattering Over a Range of Spin-0 Nuclei

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

Author: Suzuki, K. N., Gogami, T., Pandey, B., Itabashi, K., Nagao, S., Okuyama, K., Nakamura, S. N., Tang, L., Abrams, D., Akiyama, T., Androic, D., Aniol, K., Gayoso, C. Ayerbe, Bane, J., Barcus, S., Barrow, J., Bellini, V., Bhatt, H., Bhetuwal, D., Biswas, D., Camsonne, A., Castellanos, J., Chen, J-P., Chen, J., Covrig, S., Chrisman, D., Cruz-Torres, R., Das, R., Fuchey, E., Gnanvo, K., Garibaldi, F., Gautam, T., Gomez, J., Gueye, P., Hague, T. J., Hansen, O., Henry, W., Hauenstein, F., Higinbotham, D. W., Hyde, C. E., Kaneta, M., Keppel, C., Kutz, T., Lashley-Colthirst, N., Li, S., Liu, H., Mammei, J., Markowitz, P., McClellan, R. E., Meddi, F., Meekins, D., Michaels, R., Mihovilovič, M., Moyer, A., Nguyen, D., Nycz, M., Owen, V., Palatchi, C., Park, S., Petkovic, T., Premathilake, S., Reimer, P. E., Reinhold, J., Riordan, S., Rodriguez, V., Samanta, C., Santiesteban, S. N., Sawatzky, B., Širca, S., Slifer, K., Su, T., Tian, Y., Toyama, Y., Uehara, K., Urciuoli, G. M., Votaw, D., Williamson, J., Wojtsekhowski, B., Wood, S. A., Yale, B., Ye, Z., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: The small binding energy of the hypertrition leads to predictions of non-existence of bound hypernuclei for isotriplet three-body systems such as $nn\Lambda$. However, invariant mass spectroscopy at GSI has reported events that may be interpreted as the bound $nn\Lambda$ state. The $nn\Lambda$ state was sought by missing-mass spectroscopy via the $(e,e'K^+)$ reaction at Jefferson Lab's experimental Hall A. The present experiment has higher sensitivity to the $nn\Lambda$-state investigation in terms of better precision by a factor of about three. The analysis shown in this article focuses on the derivation of the reaction cross-section for the $^3{\rm{H}}(\gamma^{*},K^+)\textrm{X}$ reaction. Events that were detected in an acceptance, where a Monte Carlo simulation could reproduce the data well ($|\delta p/p| < 4\%$), were analyzed to minimize the systematic uncertainty. No significant structures were observed with the acceptance cuts, and the upper limits of the production cross-section of the $nn\Lambda$ state were obtained to be $21$ and $31~\rm{nb/sr}$ at the $90\%$ confidence level when theoretical predictions of $(-B_{\Lambda}, \Gamma) = (0.25,0.8)$ and $(0.55, 4.7)$ MeV, respectively, were assumed. The cross-section result provides valuable information for examining the existence of $nn\Lambda$., Comment: 27 pages, 12 figures
Published: 2021
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16. 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

17. Deeply Virtual Compton Scattering Cross Section at High Bjorken x_{B}.

Author: Georges, F, Rashad, MNH, Stefanko, A, Dlamini, M, Karki, B, Ali, SF, Lin, P-J, Ko, H-S, Israel, N, Adikaram, D, Ahmed, Z, Albataineh, H, Aljawrneh, B, Allada, K, Allison, S, Alsalmi, S, Androic, D, Aniol, K, Annand, J, Atac, H, Averett, T, Ayerbe Gayoso, C, Bai, X, Bane, J, Barcus, S, Bartlett, K, Bellini, V, Beminiwattha, R, Bericic, J, Biswas, D, Brash, E, Bulumulla, D, Campbell, J, Camsonne, A, Carmignotto, M, Castellano, J, Chen, C, Chen, J-P, Chetry, T, Christy, ME, Cisbani, E, Clary, B, Cohen, E, Compton, N, Cornejo, JC, Covrig Dusa, S, Crowe, B, Danagoulian, S, Danley, T, De Persio, F, Deconinck, W, Defurne, M, Desnault, C, Di, D, Duer, M, Duran, B, Ent, R, Fanelli, C, Franklin, G, Fuchey, E, Gal, C, Gaskell, D, Gautam, T, Glamazdin, O, Gnanvo, K, Gray, VM, Gu, C, Hague, T, Hamad, G, Hamilton, D, Hamilton, K, Hansen, O, Hauenstein, F, Henry, W, Higinbotham, DW, Holmstrom, T, Horn, T, Huang, Y, Huber, GM, Hyde, CE, Ibrahim, H, Jen, C-M, Jin, K, Jones, M, Kabir, A, Keppel, C, Khachatryan, V, King, PM, Li, S, Li, WB, Liu, J, Liu, H, Liyanage, A, Magee, J, Malace, S, Mammei, J, Markowitz, P, McClellan, E, Mazouz, M, and Meddi, F
Subjects: Jefferson Lab Hall A Collaboration, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract: We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton form factors (CFFs) of the nucleon as a function of x_{B}, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.
Published: 2022

18. Spectroscopic study of a possible Λnn resonance and a pair of ΣNN states using the (e,e′K+) reaction with a tritium target

Author: Pandey, B, Tang, L, Gogami, T, Suzuki, KN, Itabashi, K, Nagao, S, Okuyama, K, Nakamura, SN, Abrams, D, Afnan, IR, Akiyama, T, Androic, D, Aniol, K, Averett, T, Gayoso, C Ayerbe, Bane, J, Barcus, S, Barrow, J, Bellini, V, Bhatt, H, Bhetuwal, D, Biswas, D, Camsonne, A, Castellanos, J, Chen, J-P, Chen, J, Covrig, S, Chrisman, D, Cruz-Torres, R, Das, R, Fuchey, E, Gal, C, Gibson, BF, Gnanvo, K, Garibaldi, F, Gautam, T, Gomez, J, Gueye, P, Hague, TJ, Hansen, O, Henry, W, Hauenstein, F, Higinbotham, DW, Hyde, C, Kaneta, M, Keppel, C, Kutz, T, Lashley-Colthirst, N, Li, S, Liu, H, Mammei, J, Markowitz, P, McClellan, RE, Meddi, F, Meekins, D, Michaels, R, Mihovilovič, M, Moyer, A, Nguyen, D, Nycz, M, Owen, V, Palatchi, C, Park, S, Petkovic, T, Premathilake, S, Reimer, PE, Reinhold, J, Riordan, S, Rodriguez, V, Samanta, C, Santiesteban, SN, Sawatzky, B, Širca, S, Slifer, K, Su, T, Tian, Y, Toyama, Y, Uehara, K, Urciuoli, GM, Votaw, D, Williamson, J, Wojtsekhowski, B, Wood, S, Yale, B, Ye, Z, Zhang, J, and Zheng, X
Subjects: Nuclear and Plasma Physics, Synchrotrons and Accelerators, Physical Sciences, Nuclear and plasma physics
Abstract: A mass spectroscopy experiment with a pair of nearly identical high-resolution spectrometers and a tritium target was performed in Hall A at Jefferson Lab. Utilizing the (e,e′K+) reaction, enhancements, which may correspond to a possible Λnn resonance and a pair of ςNN states, were observed with an energy resolution of about 1.21 MeV (σ), although greater statistics are needed to make definitive identifications. An experimentally measured Λnn state may provide a unique constraint in determining the Λn interaction, for which no scattering data exist. In addition, although bound A=3 and 4 ς hypernuclei have been predicted, only an A=4 ς hypernucleus (Heς4) was found, utilizing the (K-,π-) reaction on a He4 target. The possible bound ςNN state is likely a ς0nn state, although this has to be confirmed by future experiments.
Published: 2022

19. 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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20. The cross-section measurement for the 3H(e, e′K+)nnΛ reaction

Author: Suzuki, KN, Gogami, T, Pandey, B, Itabashi, K, Nagao, S, Okuyama, K, Nakamura, SN, Tang, L, Abrams, D, Akiyama, T, Androic, D, Aniol, K, Gayoso, C Ayerbe, Bane, J, Barcus, S, Barrow, J, Bellini, V, Bhatt, H, Bhetuwal, D, Biswas, D, Camsonne, A, Castellanos, J, Chen, J-P, Chen, J, Covrig, S, Chrisman, D, Cruz-Torres, R, Das, R, Fuchey, E, Gnanvo, K, Garibaldi, F, Gautam, T, Gomez, J, Gueye, P, Hague, TJ, Hansen, O, Henry, W, Hauenstein, F, Higinbotham, DW, Hyde, CE, Kaneta, M, Keppel, C, Kutz, T, Lashley-Colthirst, N, Li, S, Liu, H, Mammei, J, Markowitz, P, McClellan, RE, Meddi, F, Meekins, D, Michaels, R, Mihovilovič, M, Moyer, A, Nguyen, D, Nycz, M, Owen, V, Palatchi, C, Park, S, Petkovic, T, Premathilake, S, Reimer, PE, Reinhold, J, Riordan, S, Rodriguez, V, Samanta, C, Santiesteban, SN, Sawatzky, B, Širca, S, Slifer, K, Su, T, Tian, Y, Toyama, Y, Uehara, K, Urciuoli, GM, Votaw, D, Williamson, J, Wojtsekhowski, B, Wood, SA, Yale, B, Ye, Z, Zhang, J, and Zheng, X
Subjects: Mathematical Sciences, Physical Sciences
Abstract: The small binding energy of the hypertriton leads to predictions of the non-existence of bound hypernuclei for isotriplet three-body systems such as nnΛ. However, invariant mass spectroscopy at GSI has reported events that may be interpreted as the bound nnΛ state. The nnΛ state was sought by missing-mass spectroscopy via the (e, e′K+) reaction at Jefferson Lab's experimental Hall A. The present experiment has higher sensitivity to the nnΛ-state investigation in terms of better precision by a factor of about three. The analysis shown in this article focuses on the derivation of the reaction cross-section for the 3H(γ∗, K+)X reaction. Events that were detected in an acceptance, where a Monte Carlo simulation could reproduce the data well (δ p/p| < 4), were analyzed to minimize the systematic uncertainty. No significant structures were observed with the acceptance cuts, and the upper limits of the production cross-section of the nnΛ state were obtained to be 21 and 31 nb sr-1 at the $90\%$ confidence level when theoretical predictions of (-BΛ, Γ) = (0.25, 0.8) MeV and (0.55, 4.7) MeV, respectively, were assumed. The cross-section result provides valuable information for examining the existence of nnΛ.
Published: 2022

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

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

Author: Adhikari, D., Albataineh, H., Androic, D., Aniol, K., Armstrong, D. S., Averett, T., Barcus, S., Bellini, V., Beminiwattha, R. S., Benesch, J. F., Bhatt, H., Pathak, D. Bhatta, Bhetuwal, D., Blaikie, B., Campagna, Q., Camsonne, A., Cates, G. D., Chen, Y., Clarke, C., Cornejo, J. C., Dusa, S. Covrig, Datta, P., Deshpande, A., Dutta, D., Feldman, C., Fuchey, E., Gal, C., Gaskell, D., Gautam, T., Gayoso, C. Ayerbe, Gericke, M., Ghosh, C., Halilovic, I., Hansen, J. -O., Hauenstein, F., Henry, W., Horowitz, C. J., Jantzi, C., Jian, S., Johnston, S., Jones, D. C., Karki, B., Katugampola, S., Keppel, C., King, P. M., King, D. E., Knauss, M., Kumar, K. S., Kutz, T., Lashley-Colthirst, N., Leverick, G., Liu, H., Liyange, N., Malace, S., Mammei, R., Mammei, J., McCaughan, M., McNulty, D., Meekins, D., Metts, C., Michaels, R., Mondal, M. M., Napolitano, J., Narayan, A., Nikolaev, D., Rashad, M. N. H., Owen, V., Palatchi, C., Pan, 14 J., Pandey, B., Park, S., Paschke, K. D., Petrusky, M., Pitt, M. L., Premathilake, S., Puckett, A. J. R., Quinn, B., Radloff, R., Rahman, S., Rathnayake, A., Reed, B. T., Reimer, P. E., Richards, R., Riordan, S., Roblin, Y., Seeds, S., Shahinyan, A., Souder, P., Tang, L., Thiel, 16 M., Tian, Y., Urciuoli, G. M., Wertz, E. W., Wojtsekhowski, B., Yale, B., Ye, T., Yoon, A., Zec, A., Zhang, W., Zhang, J., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: We report a precision measurement of the parity-violating asymmetry $A_{PV}$ in the elastic scattering of longitudinally polarized electrons from $^{208}$Pb. We measure $A_{PV}=550\pm 16 {\rm (stat)}\pm 8\ {\rm (syst)}$ parts per billion, leading to an extraction of the neutral weak form factor $F_W(Q^2 = 0.00616\ {\rm GeV}^2) = 0.368 \pm 0.013$. Combined with our previous measurement, the extracted neutron skin thickness is $R_n-R_p=0.283 \pm 0.071$~fm. The result also yields the first significant direct measurement of the interior weak density of $^{208}$Pb: $\rho^0_W = -0.0796\pm0.0036\ {\rm (exp.)}\pm0.0013\ {\rm (theo.)}\ {\rm fm}^{-3}$ leading to the interior baryon density $\rho^0_b = 0.1480\pm0.0036\ {\rm (exp.)}\pm0.0013\ {\rm (theo.)}\ {\rm fm}^{-3}$. The measurement accurately constrains the density dependence of the symmetry energy of nuclear matter near saturation density, with implications for the size and composition of neutron stars.
Published: 2021
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24. Deep Exclusive Electroproduction of π0 at High Q2 in the Quark Valence Regime

Author: Dlamini, M, Karki, B, Ali, SF, Lin, P-J, Georges, F, Ko, H-S, Israel, N, Rashad, MNH, Stefanko, A, Adikaram, D, Ahmed, Z, Albataineh, H, Aljawrneh, B, Allada, K, Allison, S, Alsalmi, S, Androic, D, Aniol, K, Annand, J, Atac, H, Averett, T, Ayerbe Gayoso, C, Bai, X, Bane, J, Barcus, S, Bartlett, K, Bellini, V, Beminiwattha, R, Bericic, J, Biswas, D, Brash, E, Bulumulla, D, Campbell, J, Camsonne, A, Carmignotto, M, Castellano, J, Chen, C, Chen, J-P, Chetry, T, Christy, ME, Cisbani, E, Clary, B, Cohen, E, Compton, N, Cornejo, JC, Covrig Dusa, S, Crowe, B, Danagoulian, S, Danley, T, De Persio, F, Deconinck, W, Defurne, M, Desnault, C, Di, D, Duer, M, Duran, B, Ent, R, Fanelli, C, Franklin, G, Fuchey, E, Gal, C, Gaskell, D, Gautam, T, Glamazdin, O, Gnanvo, K, Gray, VM, Gu, C, Hague, T, Hamad, G, Hamilton, D, Hamilton, K, Hansen, O, Hauenstein, F, Henry, W, Higinbotham, DW, Holmstrom, T, Horn, T, Huang, Y, Huber, GM, Hyde, C, Ibrahim, H, Jen, C-M, Jin, K, Jones, M, Kabir, A, Keppel, C, Khachatryan, V, King, PM, Li, S, Li, W, Liu, J, Liu, H, Liyanage, A, Magee, J, Malace, S, Mammei, J, Markowitz, P, McClellan, E, Meddi, F, and Meekins, D
Subjects: Jefferson Lab Hall A Collaboration, Mathematical Sciences, Physical Sciences, Engineering, General Physics
Abstract: We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of x_{B} (0.36, 0.48, and 0.60) and Q^{2} (3.1 to 8.4 GeV^{2}) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσ_{T}/dt+εdσ_{L}/dt, dσ_{TT}/dt, dσ_{LT}/dt, and dσ_{LT^{'}}/dt are extracted as a function of the proton momentum transfer t-t_{min}. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.
Published: 2021

25. Deep exclusive electroproduction of $\pi^0$ at high $Q^2$ in the quark valence regime

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

Author: Accardi, A., Afanasev, A., Albayrak, I., Ali, S. F., Amaryan, M., Annand, J. R. M., Arrington, J., Asaturyan, A., Atac, H., Avakian, H., Averett, T., Gayoso, C. Ayerbe, Bai, X., Barion, L., Battaglieri, M., Bellini, V., Beminiwattha, R., Benmokhtar, F., Berdnikov, V. V., Bernauer, J. C., Bertone, V., Bianconi, A., Biselli, A., Bisio, P., Blunden, P., Boer, M., Bondì, M., Brinkmann, K. -T., Briscoe, W. J., Burkert, V., Cao, T., Camsonne, A., Capobianco, R., Cardman, L., Carmignotto, M., Caudron, M., Causse, L., Celentano, A., Chatagnon, P., Chen, J. -P., Chetry, T., Ciullo, G., Cline, E., Cole, P. L., Contalbrigo, M., Costantini, G., D'Angelo, A., Darmé, L., Day, D., Defurne, M., De Napoli, M., Deur, A., De Vita, R., D'Hose, N., Diehl, S., Diefenthaler, M., Dongwi, B., Dupré, R., Dutrieux, H., Dutta, D., Ehrhart, M., Fassi, L. El, Elouadrhiri, L., Ent, R., Erler, J., Fernando, I. P., Filippi, A., Flay, D., Forest, T., Fuchey, E., Fucini, S., Furletova, Y., Gao, H., Gaskell, D., Gasparian, A., Gautam, T., Girod, F. -X., Gnanvo, K., Grames, J., Grauvoge, G. N., Gueye, P., Guidal, M., Habet, S., Hague, T. J., Hamilton, D. J., Hansen, O., Hasell, D., Hattawy, M., Higinbotham, D. W., Hobart, A., Horn, T., Hyde, C. E., Ibrahim, H., Ilyichev, A., Italiano, A., Joo, K., Joosten, S. J., Khachatryan, V., Kalantarians, N., Kalicy, G., Karky, B., Keller, D., Keppel, C., Kerver, M., Khandaker, M., Kim, A., Kim, J., King, P. M., Kinney, E., Klimenko, V., Ko, H. -S., Kohl, M., Kozhuharov, V., Kriesten, B. T., Krnjaic, G., Kubarovsky, V., Kutz, T., Lanza, L., Leali, M., Lenisa, P., Liyanage, N., Liu, Q., Liuti, S., Mammei, J., Mantry, S., Marchand, D., Markowitz, P., Marsicano, L., Mascagna, V., Mazouz, M., McCaughan, M., McKinnon, B., McNulty, D., Melnitchouk, W., Metz, A., Meziani, Z. -E., Migliorati, S., Mihovilovic, M., Milner, R., Mkrtchyan, A., Mkrtchyan, H., Movsisyan, A., Moutarde, H., Muhoza, M., Camacho, C. Muñoz, Murphy, J., Nadel-Turonski, P., Nardi, E., Nazeer, J., Niccolai, S., Niculescu, G., Novotny, R., Owens, J. F., Paolone, M., Pappalardo, L., Paremuzyan, R., Pasquini, B., Pasyuk, E., Patel, T., Pegg, I., Peng, C., Perera, D., Poelker, M., Price, K., Puckett, A. J. R., Raggi, M., Randazzo, N., Rashad, M. N. H., Rathnayake, M., Raue, B., Reimer, P. E., Rinaldi, M., Rizzo, A., Roblin, Y., Roche, J., Rondon-Aramayo, O., Sabatié, F., Salmè, G., Santopinto, E., Estrada, R. Santos, Sawatzky, B., Schmidt, A., Schweitzer, P., Scopetta, S., Sergeyeva, V., Shabestari, M., Shahinyan, A., Sharabian, Y., Širca, S., Smith, E. S., Sokhan, D., Somov, A., Sparveris, N., Spata, M., Spiesberger, H., Spreafico, M., Stepanyan, S., Stoler, P., Strakovsky, I., Suleiman, R., Suresh, M., Sznajder, P., Szumila-Vance, H., Tadevosyan, V., Tadepalli, A. S., Thomas, A. W., Tiefenback, M., Trotta, R., Ungaro, M., Valente, P., Vanderhaeghen, M., Venturelli, L., Voskanyan, H., Voutier, E., Wojtsekhowski, B., Wood, M. H., Wood, S., Xie, J., Xiong, W., Ye, Z., Yurov, M., Zaunick, H. -G., Zhamkochyan, S., Zhang, J., Zhang, S., Zhao, S., Zhao, Z. W., Zheng, X., Zhou, J., and Zorn, C.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental programs at the next generation of lepton accelerators. In the context of the hadronic physics program at Jefferson Lab (JLab), positron beams are complementary, even essential, tools for a precise understanding of the electromagnetic structure of nucleons and nuclei, in both the elastic and deep-inelastic regimes. For instance, elastic scattering of polarized and unpolarized electrons and positrons from the nucleon enables a model independent determination of its electromagnetic form factors. Also, the deeply-virtual scattering of polarized and unpolarized electrons and positrons allows unambiguous separation of the different contributions to the cross section of the lepto-production of photons and of lepton-pairs, enabling an accurate determination of the nucleons and nuclei generalized parton distributions, and providing an access to the gravitational form factors. Furthermore, positron beams offer the possibility of alternative tests of the Standard Model of particle physics through the search of a dark photon, the precise measurement of electroweak couplings, and the investigation of charged lepton flavor violation. This document discusses the perspectives of an experimental program with high duty-cycle positron beams at JLab., Comment: 18 pages, 7 figures This version superseeds the previous version which scientific content was decomposed into several more elaborated articles. All of these articles will be collected in the EPJ A Topical Issue about "Positron beam and physics at Jefferson Lab (e+@Jlab)"
Published: 2020
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27. 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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28. 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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29. 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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30. 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

31. 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

32. Deep exclusive electroproduction of $π^0$ at high $Q^2$ in the quark valence regime

Author: Collaboration, The Jefferson Lab Hall A, Dlamini, M, Karki, B, Ali, SF, Lin, P-J, Georges, F, Ko, H-S, Israel, N, Rashad, MNH, Stefanko, A, Adikaram, D, Ahmed, Z, Albataineh, H, Aljawrneh, B, Allada, K, Allison, S, Alsalmi, S, Androic, D, Aniol, K, Annand, J, Atac, H, Averett, T, Gayoso, C Ayerbe, Bai, X, Bane, J, Barcus, S, Bartlett, K, Bellini, V, Beminiwattha, R, Bericic, J, Biswas, D, Brash, E, Bulumulla, D, Campbell, J, Camsonne, A, Carmignotto, M, Castellano, J, Chen, C, Chen, J-P, Chetry, T, Christy, ME, Cisbani, E, Clary, B, Cohen, E, Compton, N, Cornejo, JC, Dusa, S Covrig, Crowe, B, Danagoulian, S, Danley, T, Persio, F De, Deconinck, W, Defurne, M, Desnault, C, Di, D, Duer, M, Duran, B, Ent, R, Fanelli, C, Franklin, G, Fuchey, E, Gal, C, Gaskell, D, Gautam, T, Glamazdin, O, Gnanvo, K, Gray, VM, Gu, C, Hague, T, Hamad, G, Hamilton, D, Hamilton, K, Hansen, O, Hauenstein, F, Henry, W, Higinbotham, DW, Holmstrom, T, Horn, T, Huang, Y, Huber, GM, Hyde, C, Ibrahim, H, Jen, C-M, Jin, K, Jones, M, Kabir, A, Keppel, C, Khachatryan, V, King, PM, Li, S, Li, W, Liu, J, Liu, H, Liyanage, A, Magee, J, Malace, S, Mammei, J, Markowitz, P, McClellan, E, and Meddi, F
Subjects: hep-ex, nucl-ex
Abstract: We report measurements of the exclusive neutral pion electroproduction crosssection off protons at large values of $x_B$ (0.36, 0.48 and 0.60) and $Q^2$(3.1 to 8.4 GeV$^2$) obtained from Jefferson Lab Hall A experiment E12-06-014.The corresponding structure functions $d\sigma_L/dt+\epsilon d\sigma_T/dt$,$d\sigma_{TT}/dt$, $d\sigma_{LT}/dt$ and $d\sigma_{LT'}/dt$ are extracted as afunction of the proton momentum transfer $t-t_{min}$. The results suggest theamplitude for transversely polarized virtual photons continues to dominate thecross-section throughout this kinematic range. The data are well described bycalculations based on transversity Generalized Parton Distributions coupled toa helicity flip Distribution Amplitude of the pion, thus providing a unique wayto probe the structure of the nucleon.
Published: 2020

33. A fast-switching magnet serving a spallation-driven ultracold neutron source

Author: Ahmed, S., Altiere, E., Andalib, T., Barnes, M. J., Bell, B., Bidinosti, C. P., Bylinsky, Y., Chak, J., Das, M., Davis, C. A., Fischer, F., Franke, B., Gericke, M. T. W., Giampa, P., Hahn, M., Hansen-Romu, S., Hatanaka, K., Hayamizu, T., Jamieson, B., Jones, D., Katsika, K., Kawasaki, S., Kikawa, T., Klassen, W., Konaka, A., Korkmaz, E., Kuchler, F., Kurchaninov, L., Lang, M., Lee, L., Lindner, T., Madison, K. W., Mammei, J., Mammei, R., Martin, J. W., Matsumiya, R., Miller, E., Momose, T., Picker, R., Pierre, E., Ramsay, W. D., Rao, Y. -N., Rawnsley, W. R., Rebenitsch, L., Schreyer, W., Sidhu, S., Vanbergen, S., van Oers, W. T. H., Watanabe, Y. X., and Yosifov, D.
Subjects: Physics - Accelerator Physics, Nuclear Experiment, Physics - Instrumentation and Detectors
Abstract: A fast-switching, high-repetition-rate magnet and power supply have been developed for and operated at TRIUMF, to deliver a proton beam to the new ultracold neutron (UCN) facility. The facility possesses unique operational requirements: a time-averaged beam current of 40~$\mu$A with the ability to switch the beam on or off for several minutes. These requirements are in conflict with the typical operation mode of the TRIUMF cyclotron which delivers nearly continuous beam to multiple users. To enable the creation of the UCN facility, a beam-sharing arrangement with another facility was made. The beam sharing is accomplished by the fast-switching (kicker) magnet which is ramped in 50~$\mu$s to a current of 193~A, held there for approximately 1~ms, then ramped down in the same short period of time. This achieves a 12~mrad deflection which is sufficient to switch the proton beam between the two facilities. The kicker magnet relies on a high-current, low-inductance coil connected to a fast-switching power supply that is based on insulated-gate bipolar transistors (IGBTs). The design and performance of the kicker magnet system and initial beam delivery results are reported., Comment: 16 pages, 21 figures
Published: 2019
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34. 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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35. 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

36. Characterization of electroless nickel-phosphorus plating for ultracold-neutron storage

Author: Akatsuka, H., Andalib, T., Bell, B., Berean-Dutcher, J., Bernier, N., Bidinosti, C.P., Cude-Woods, C., Currie, S.A., Davis, C.A., Franke, B., Gaur, R., Giampa, P., Hansen-Romu, S., Hassan, M.T., Hatanaka, K., Higuchi, T., Gibson, C., Ichikawa, G., Ide, I., Imajo, S., Ito, T.M., Jamieson, B., Kawasaki, S., Kitaguchi, M., Klassen, W., Korkmaz, E., Kuchler, F., Lang, M., Lavvaf, M., Lindner, T., Makela, M., Mammei, J., Mammei, R., Martin, J.W., Matsumiya, R., Miller, E., Mishima, K., Momose, T., Morawetz, S., Morris, C.L., Ong, H.J., O’Shaughnessy, C.M., Pereira-Wilson, M., Picker, R., Piermaier, F., Pierre, E., Schreyer, W., Sidhu, S., Stang, D., Tiepo, V., Vanbergen, S., Wang, R., Wong, D., and Yamamoto, N.
Published: 2023
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37. The Nab Experiment: A Precision Measurement of Unpolarized Neutron Beta Decay

Author: Fry, J., Alarcon, R., Baessler, S., Balascuta, S., Barron-Palos, L., Bailey, T., Bass, K., Birge, N., Blose, A., Borissenko, D., Bowman, J. D., Broussard, L. J., Bryant, A. T., Byrne, J., Calarco, J. R., Caylor, J., Chang, K., Chupp, T., Cianciolo, T. V., Crawford, C., Ding, X., Doyle, M., Fan, W., Farrar, W., Fomin, N., Frlez, E., Gericke, M. T., Gervais, M., Gluck, F., Greene, G. L., Grzywacz, R. K., Gudkov, V., Hamblen, J., Hayes, C., Hendrus, C., Ito, T., Jezghani, A., Li, H., Makela, M., Macsai, N., Mammei, J., Mammei, R., Martinez, M., Mathews, D. G., McCrea, M., McGaughey, P., McLaughlin, C. D., Mueller, P., van Petten, D., Penttila, S. I., Perryman, D. E., Picker, R., Pierce, J., Pocanic, D., Qian, Y., Ramsey, J., Randall, G., Riley, G., Rykaczewski, K. P., Salas-Bacci, A., Samiei, S., Scott, E. M., Shelton, T., Sjue, S. K., Smith, A., Smith, E., Stevens, E., Wexler, J., Whitehead, R., Wilburn, W. S., Young, A., and Zeck, B.
Subjects: Nuclear Experiment
Abstract: Neutron beta decay is one of the most fundamental processes in nuclear physics and provides sensitive means to uncover the details of the weak interaction. Neutron beta decay can evaluate the ratio of axial-vector to vector coupling constants in the standard model, $\lambda = g_A / g_V$, through multiple decay correlations. The Nab experiment will carry out measurements of the electron-neutrino correlation parameter $a$ with a precision of $\delta a / a = 10^{-3}$ and the Fierz interference term $b$ to $\delta b = 3\times10^{-3}$ in unpolarized free neutron beta decay. These results, along with a more precise measurement of the neutron lifetime, aim to deliver an independent determination of the ratio $\lambda$ with a precision of $\delta \lambda / \lambda = 0.03\%$ that will allow an evaluation of $V_{ud}$ and sensitively test CKM unitarity, independent of nuclear models. Nab utilizes a novel, long asymmetric spectrometer that guides the decay electron and proton to two large area silicon detectors in order to precisely determine the electron energy and an estimation of the proton momentum from the proton time of flight. The Nab spectrometer is being commissioned at the Fundamental Neutron Physics Beamline at the Spallation Neutron Source at Oak Ridge National Lab. We present an overview of the Nab experiment and recent updates on the spectrometer, analysis, and systematic effects., Comment: Presented at PPNS2018
Published: 2018
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38. A beamline for fundamental neutron physics at TRIUMF

Author: Ahmed, S., Andalib, T., Barnes, M. J., Bidinosti, C. B., Bylinsky, Y., Chak, J., Das, M., Davis, C. A., Franke, B., Gericke, M. T. W., Giampa, P., Hahn, M., Hansen-Romu, S., Hatanaka, K., Jamieson, B., Jones, D., Katsika, K., Kawasaki, S., Klassen, W., Konaka, A., Korkmaz, E., Kuchler, F., Kurchaninov, L., Lang, M., Lee, L., Lindner, T., Madison, K. W., Mammei, J., Mammei, R., Martin, J. W., Matsumiya, R., Picker, R., Pierre, E., Ramsay, W. D., Rao, Y. -N., Rawnsley, W. R., Rebenitsch, L., Remon, C. A., Schreyer, W., Sikora, A., Sidhu, S., Sonier, J., Thorsteinson, B., Vanbergen, S., van Oers, W. T. H., Watanabe, Y. X., and Yosifov, D.
Subjects: Physics - Instrumentation and Detectors
Abstract: This article describes the new primary proton beamline 1U at TRIUMF. The purpose of this beamline is to produce ultracold neutrons (UCN) for fundamental-physics experiments. It delivers up to 40 microA of 480 MeV protons from the TRIUMF cyclotron to a tungsten spallation target and uses a fast kicker to share the beam between the Center for Molecular and Materials Science and UCN. The beamline has been successfully commissioned and operated with a beam current up to 10 microA, facilitating first large-scale UCN production in Canada.
Published: 2018
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39. First ultracold neutrons produced at TRIUMF

Author: Ahmed, S., Altiere, E., Andalib, T., Bell, B., Bidinosti, C. P., Cudmore, E., Das, M., Davis, C. A., Franke, B., Gericke, M., Giampa, P., Gnyp, P., Hansen-Romu, S., Hatanaka, K., Hayamizu, T., Jamieson, B., Jones, D., Kawasaki, S., Kikawa, T., Kitaguchi, M., Klassen, W., Konaka, A., Korkmaz, E., Kuchler, F., Lang, M., Lee, L., Lindner, T., Madison, K. W., Makida, Y., Mammei, J., Mammei, R., Martin, J. W., Matsumiya, R., Miller, E., Mishima, K., Momose, T., Okamura, T., Page, S., Picker, R., Pierre, E., Ramsay, W. D., Rebenitsch, L., Rehm, F., Schreyer, W., Shimizu, H. M., Sidhu, S., Sikora, A., Smith, J., Tanihata, I., Thorsteinson, B., Vanbergen, S., van Oers, W. T. H., and Watanabe, Y. X.
Subjects: Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract: We installed a source for ultracold neutrons at a new, dedicated spallation target at TRIUMF. The source was originally developed in Japan and uses a superfluid-helium converter cooled to 0.9$\,$K. During an extensive test campaign in November 2017, we extracted up to 325000 ultracold neutrons after a one-minute irradiation of the target, over three times more than previously achieved with this source. The corresponding ultracold-neutron density in the whole production and guide volume is 5.3$\,$cm$^{-3}$. The storage lifetime of ultracold neutrons in the source was initially 37$\,$s and dropped to 24$\,$s during the eighteen days of operation. During continuous irradiation of the spallation target, we were able to detect a sustained ultracold-neutron rate of up to 1500$\,$s$^{-1}$. Simulations of UCN production, UCN transport, temperature-dependent UCN yield, and temperature-dependent storage lifetime show excellent agreement with the experimental data and confirm that the ultracold-neutron-upscattering rate in superfluid helium is proportional to $T^7$., Comment: 8 pages, 10 figures
Published: 2018
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40. 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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41. 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

42. 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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43. 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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44. 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

45. 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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46. Design and Prototyping of a Novel Toroidal Magnet System for MOLLER Experiment at Jefferson Lab

Author: Kashy, D., Gopinath, S., Sun, E., Ghoshal, P., Fast, J., Sinnott, M., Lamont, J., Dion, M. P., Fair, R., Kumar, K., Mammei, J., Rajput-Ghoshal, R., and Ihloff, E.
Abstract: The Thomas Jefferson National Accelerator Facility (JLab) has designed a unique spectrometer system to measure the weak interaction between electrons. The experiment— Measurement of Lepton-Lepton Electroweak Reaction (MOLLER)—requires leveraging the recent 12 GeV electron beam upgrade and will run in JLab for three years. Focusing the signal for the MOLLER experiment requires five water-cooled toroidal magnets, each with unique geometry and with 7-fold symmetry. The five magnets operate in a vacuum and provide the magnetic field required to separate the incident beam electrons scattered from the target electrons (Møller scattering) and protons (elastic e-p scattering) in a liquid hydrogen target. The conceptual design was developed by the MOLLER Collaboration and was given to JLab in the form of amp turns and physical location, with additional physics requirements. This article presents prototyping of the coils and magnet support system and discusses the lessons learned during the process along with the plans for full magnet testing and installation. The JLab Magnet Group along with the MOLLER Collaboration developed the specification document that includes keep out zones to design the set of magnets. JLab contracted the design of the first toroid magnet (TM0) of the magnet system to Massachusetts Institute of Technology. The other four toroid magnets (TM1 through TM4) have been designed by JLab and are in the process of fabrication and assembly. Prototype coils of TM1-TM4 were fabricated by Everson-Tesla Incorporated, PA (USA). This article presents the unique challenges of the design, alignment, high current density, operating range, high radiation dose, and vacuum environment.
Published: 2024
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47. Electroexcitation of the $\Delta^{+}(1232)$ at low momentum transfer

Author: Blomberg, A., Anez, D., Sparveris, N., Sarty, A., Paolone, M., Gilad, S., Higinbotham, D., Abudureyimu, A. R., Ahmed, Z., Albataineh, H., Allada, K., Anderson, B., Aniol, K., Annand, J., Averett, T., Baghdasaryan, H., Bai, X., Beck, A., Beck, S., Bellini, V., Benmokhtar, F., Boeglin, W., Camacho, C. M., Camsonne, A., Chen, C., Chen, J. P., Chirapatpimol, K., Cisbani, E., Dalton, M., Deconinck, W., Defurne, M., De Leo, R., Flay, D., Fomin, N., Friend, M., Frullani, S., Fuchey, E., Garibaldi, F., Gilman, R., Gu, C., Hamilton, D., Hanretty, C., Hansen, O., Shabestari, M. Hashemi, Holmstrom, T., Huang, M., Iqbal, S., Kalantarians, N., Kang, H., Kelleher, A., Khandaker, M., Leckey, J., LeRose, J., Lindgren, R., Long, E., Mammei, J., Margaziotis, D. J., Jimenez-Arguello, A. Marti, Meziani, Z. E., Mihovilovic, M., Muangma, N., Norum, B., Nuruzzaman, Pan, K., Phillips, S., Polychronopoulou, A., Pomerantz, I., Posik, M., Punjabi, V., Qian, X., Reimer, P. E., Riordan, S., Ron, G., Saha, A., Schulte, E., Selvy, L., Sirca, S., Sjoegren, J., Subedi, R., Sulkosky, V., Tireman, W., Wang, D., Watson, J., Weinstein, L., Wojtsekhowski, B., Yan, W., Yaron, I., Ye, Z., Zhan, X., Zhang, Y., Zhang, J., Zhao, B., Zhao, Z., Zheng, X., and Zhu, P.
Subjects: Nuclear Experiment
Abstract: We report on new p$(e,e^\prime p)\pi^\circ$ measurements at the $\Delta^{+}(1232)$ resonance at the low momentum transfer region. The mesonic cloud dynamics is predicted to be dominant and rapidly changing in this kinematic region offering a test bed for chiral effective field theory calculations. The new data explore the low $Q^2$ dependence of the resonant quadrupole amplitudes while extending the measurements of the Coulomb quadrupole amplitude to the lowest momentum transfer ever reached. The results disagree with predictions of constituent quark models and are in reasonable agreement with dynamical calculations that include pion cloud effects, chiral effective field theory and lattice calculations. The reported measurements suggest that improvement is required to the theoretical calculations and provide valuable input that will allow their refinements.
Published: 2015
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48. The MOLLER Experiment: An Ultra-Precise Measurement of the Weak Mixing Angle Using M{\o}ller Scattering

Author: MOLLER Collaboration, Benesch, J., Brindza, P., Carlini, R. D., Chen, J-P., Chudakov, E., Covrig, S., Dalton, M. M., Deur, A., Gaskell, D., Gavalya, A., Gomez, J., Higinbotham, D. W., Keppel, C., Meekins, D., Michaels, R., Moffit, B., Roblin, Y., Suleiman, R., Wines, R., Wojtsekhowski, B., Cates, G., Crabb, D., Day, D., Gnanvo, K., Keller, D., Liyanage, N., Nelyubin, V. V., Nguyen, H., Norum, B., Paschke, K., Sulkosky, V., Zhang, J., Zheng, X., Birchall, J., Blunden, P., Gericke, M. T. W., Falk, W. R., Lee, L., Mammei, J., Page, S. A., van Oers, W. T. H., Dehmelt, K., Deshpande, A., Feege, N., Hemmick, T. K., Kumar, K. S., Kutz, T., Miskimen, R., Ramsey-Musolf, M. J., Riordan, S., Saylor, N. Hirlinger, Bessuille, J., Ihloff, E., Kelsey, J., Kowalski, S., Silwal, R., De Cataldo, G., De Leo, R., Di Bari, D., Lagamba, L., Bellini, E. NappiV., Mammoliti, F., Noto, F., Sperduto, M. L., Sutera, C. M., Cole, P., Forest, T. A., Khandekar, M., McNulty, D., Aulenbacher, K., Baunack, S., Maas, F., Tioukine, V., Gilman, R., Myers, K., Ransome, R., Tadepalli, A., Beniniwattha, R., Holmes, R., Souder, P., Armstrong, D. S., Averett, T. D., Deconinck, W., Duvall, W., Lee, A., Pitt, M. L., Dunne, J. A., Dutta, D., Fassi, L. El, De Persio, F., Meddi, F., Urciuoli, G. M., Cisbani, E., Fanelli, C., Garibaldi, F., Johnston, K., Simicevic, N., Wells, S., King, P. M., Roche, J., Arrington, J., Reimer, P. E., Franklin, G., Quinn, B., Ahmidouch, A., Danagoulian, S., Glamazdin, O., Pomatsalyuk, R., Mammei, R., Martin, J. W., Holmstrom, T., Erler, J., Kolomensky, Yu. G., Napolitano, J., Aniol, K. A., Ramsay, W. D., Korkmaz, E., Spayde, D. T., Benmokhtar, F., Del Dotto, A., Perrino, R., Barkanova, S., Aleksejevs, A., and Singh, J.
Subjects: Nuclear Experiment, High Energy Physics - Phenomenology
Abstract: The physics case and an experimental overview of the MOLLER (Measurement Of a Lepton Lepton Electroweak Reaction) experiment at the 12 GeV upgraded Jefferson Lab are presented. A highlight of the Fundamental Symmetries subfield of the 2007 NSAC Long Range Plan was the SLAC E158 measurement of the parity-violating asymmetry $A_{PV}$ in polarized electron-electron (M{\o}ller) scattering. The proposed MOLLER experiment will improve on this result by a factor of five, yielding the most precise measurement of the weak mixing angle at low or high energy anticipated over the next decade. This new result would be sensitive to the interference of the electromagnetic amplitude with new neutral current amplitudes as weak as $\sim 10^{-3}\cdot G_F$ from as yet undiscovered dynamics beyond the Standard Model. The resulting discovery reach is unmatched by any proposed experiment measuring a flavor- and CP-conserving process over the next decade, and yields a unique window to new physics at MeV and multi-TeV scales, complementary to direct searches at high energy colliders such as the Large Hadron Collider (LHC). The experiment takes advantage of the unique opportunity provided by the upgraded electron beam energy, luminosity, and stability at Jefferson Laboratory and the extensive experience accumulated in the community after a round of recent successfully completed parity-violating electron scattering experiments
Published: 2014

49. Electroexcitation of the Δ+(1232) at low momentum transfer

Author: Blomberg, A, Anez, D, Sparveris, N, Sarty, AJ, Paolone, M, Gilad, S, Higinbotham, D, Ahmed, Z, Albataineh, H, Allada, K, Anderson, B, Aniol, K, Annand, J, Arrington, J, Averett, T, Baghdasaryan, H, Bai, X, Beck, A, Beck, S, Bellini, V, Benmokhtar, F, Boeglin, W, Camacho, CM, Camsonne, A, Chen, C, Chen, JP, Chirapatpimol, K, Cisbani, E, Dalton, M, Deconinck, W, Defurne, M, De Leo, R, Flay, D, Fomin, N, Friend, M, Frullani, S, Fuchey, E, Garibaldi, F, Gilman, R, Gu, C, Hamilton, D, Hanretty, C, Hansen, O, Hashemi Shabestari, M, Hen, O, Holmstrom, T, Huang, M, Iqbal, S, Kalantarians, N, Kang, H, Kelleher, A, Khandaker, M, Korover, I, Leckey, J, LeRose, J, Lindgren, R, Long, E, Mammei, J, Margaziotis, DJ, Martí Jimenez-Arguello, A, Meekins, D, Meziani, ZE, Mihovilovic, M, Muangma, N, Norum, B, Nuruzzaman, Pan, K, Phillips, S, Piasetzky, E, Polychronopoulou, A, Pomerantz, I, Posik, M, Punjabi, V, Qian, X, Rakhman, A, Reimer, PE, Riordan, S, Ron, G, Saha, A, Schulte, E, Selvy, L, Shneor, R, Sirca, S, Sjoegren, J, Subedi, R, Sulkosky, V, Tireman, W, Wang, D, Watson, J, Wojtsekhowski, B, Yan, W, Yaron, I, Ye, Z, Zhan, X, Zhang, J, Zhang, Y, Zhao, B, Zhao, Z, Zheng, X, and Zhu, P
Subjects: CMR, Pion electroproduction, Nucleon deformation, Nuclear & Particles Physics, Mathematical Physics, Astronomical and Space Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics
Abstract: We report on new measurements at the resonance at the low momentum transfer region, where the mesonic cloud dynamics is predicted to be dominant and rapidly changing, offering a test bed for chiral effective field theory calculations. The new data explore the dependence of the resonant quadrupole amplitudes and for the first time indicate that the Electric and the Coulomb quadrupole amplitudes converge as. The measurements of the Coulomb quadrupole amplitude have been extended to the lowest momentum transfer ever reached, and suggest that more than half of its magnitude is attributed to the mesonic cloud in this region. The new data disagree with predictions of constituent quark models and are in reasonable agreement with dynamical calculations that include pion cloud effects, chiral effective field theory and lattice calculations. The measurements indicate that improvement is required to the theoretical calculations and provide valuable input that will allow their refinements.
Published: 2016

50. The Q_weak Experimental Apparatus

Author: Qweak Collaboration, Allison, T., Anderson, M., Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T. D., Averill, R., Balewski, J., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Bessuille, J., Birchall, J., Bonnell, E., Bowman, J., Brindza, P., Brown, D. B., Carlini, R. D., Cates, G. D., Cavness, B., Clark, G., Cornejo, J. C., Dusa, S. Covrig, Dalton, M. M., Davis, C. A., Dean, D. C., Deconinck, W., Diefenbach, J., Dow, K., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Echols, J. R., Elaasar, M., Falk, W. R., Finelli, K. D., Finn, J. M., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hansknecht, J., Harrison, D. J., Henderson, E., Hoskins, J. R., Ihloff, E., Johnston, K., Jones, D., Jones, M., Jones, R., Kargiantoulakis, M., Kelsey, J., Khan, N., King, P. M., Korkmaz, E., Kowalski, S., Kubera, A., Leacock, J., Leckey, J. P., Lee, A. R., Lee, J. H., Lee, L., Liang, Y., MacEwan, S., Mack, D., Magee, J. A., Mahurin, R., Mammei, J., Martin, J. W., McCreary, A., McDonald, M. H., McHugh, M. J., Medeiros, P., Meekins, D., Mei, J., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Musson, J., Mesick, K. E., Narayan, A., Ndukum, L. Z., Nelyubin, V., 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., Roberts, W. R., Roche, J., Rose, P. W., Sawatzky, B., Seva, T., Shabestari, M. H., Silwal, R., Simicevic, N., Smith, G. R., Sobczynski, S., Solvignon, P., Spayde, D. T., Stokes, B., Storey, D. W., Subedi, A., Subedi, R., Suleiman, R., Tadevosyan, V., Tobias, W. A., Tvaskis, V., Urban, E., Waidyawansa, B., Wang, P., Wells, S. P., Wood, S. A., Yang, S., Zhamkochyan, S., and Zielinski, R. B.
Subjects: Physics - Instrumentation and Detectors, Nuclear Experiment, Physics - Accelerator Physics
Abstract: The Jefferson Lab Q_weak experiment determined the weak charge of the proton by measuring the parity-violating elastic scattering asymmetry of longitudinally polarized electrons from an unpolarized liquid hydrogen target at small momentum transfer. A custom apparatus was designed for this experiment to meet the technical challenges presented by the smallest and most precise ${\vec{e}}$p asymmetry ever measured. Technical milestones were achieved at Jefferson Lab in target power, beam current, beam helicity reversal rate, polarimetry, detected rates, and control of helicity-correlated beam properties. The experiment employed 180 microA of 89% longitudinally polarized electrons whose helicity was reversed 960 times per second. The electrons were accelerated to 1.16 GeV and directed to a beamline with extensive instrumentation to measure helicity-correlated beam properties that can induce false asymmetries. Moller and Compton polarimetry were used to measure the electron beam polarization to better than 1%. The electron beam was incident on a 34.4 cm liquid hydrogen target. After passing through a triple collimator system, scattered electrons between 5.8 degrees and 11.6 degrees were bent in the toroidal magnetic field of a resistive copper-coil magnet. The electrons inside this acceptance were focused onto eight fused silica Cerenkov detectors arrayed symmetrically around the beam axis. A total scattered electron rate of about 7 GHz was incident on the detector array. The detectors were read out in integrating mode by custom-built low-noise pre-amplifiers and 18-bit sampling ADC modules. The momentum transfer Q^2 = 0.025 GeV^2 was determined using dedicated low-current (~100 pA) measurements with a set of drift chambers before (and a set of drift chambers and trigger scintillation counters after) the toroidal magnet., Comment: 48 pages, 36 figures. Accepted by Nuclear Instruments and Methods A
Published: 2014

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