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1. Fundamental Symmetries, Neutrons, and Neutrinos (FSNN): Whitepaper for the 2023 NSAC Long Range Plan

Author: Acharya, B., Adams, C., Aleksandrova, A. A., Alfonso, K., An, P., Baeßler, S., Balantekin, A. B., Barbeau, P. S., Bellini, F., Bellini, V., Beminiwattha, R. S., Bernauer, J. C., Bhattacharya, T., Bishof, M., Bolotnikov, A. E., Breur, P. A., Brodeur, M., Brodsky, J. P., Broussard, L. J., Brunner, T., Burdette, D. P., Caylor, J., Chiu, M., Cirigliano, V., Clark, J. A., Clayton, S. M., Daniels, T. V., Darroch, L., Davoudi, Z., de Gouvêa, A., Dekens, W., Demarteau, M., DeMille, D., Deshpande, A., Detwiler, J. A., Dodson, G. W., Dolinski, M. J., Elliott, S. R., Engel, J., Erler, J., Filippone, B. W., Fomin, N., Formaggio, J. A., Friesen, F. Q. L., Fry, J., Fujikawa, B. K., Fuller, G., Fuyuto, K., Gallant, A. T., Gallina, G., Ruiz, A. Garcia, Ruiz, R. F. Garcia, Gardner, S., Gonzalez, F. M., Gratta, G., Gruszko, J., Gudkov, V., Guiseppe, V. E., Gutierrez, T. D., Hansen, E. V., Hardy, C. A., Haxton, W. C., Hayen, L., Hedges, S., Heeger, K. M., Heffner, M., Heise, J., Henning, R., Hergert, H., Hertzog, D. W., Aguilar, D. Hervas, Holt, J. D., Hoogerheide, S. F., Hoppe, E. W., Horoi, M., Howell, C. R., Huang, M., Hutzler, N. R., Imam, K., Ito, T. M., Jamil, A., Janssens, R. V., Jayich, A. M., Jones, B. J. P., Kammel, P., Liu, K. F., Khachatryan, V., King, P. M., Klein, J. R., Kneller, J. P., Kolomensky, Yu. G., Korsch, W., Krücken, R., Kumar, K. S., Launey, K. D., Lawrence, D., Leach, K. G., Lehnert, B., Lenardo, B. G., Li, Z., Lin, H. -W., Longfellow, B., Lopez-Caceres, S., Lunardini, C., MacLellan, R., Markoff, D. M., Maruyama, R. H., Mathews, D. G., Melconian, D., Mereghetti, E., Mohanmurthy, P., Moore, D. C., Mueller, P. E., Mumm, H. P., Nazarewicz, W., Newby, J., Nicholson, A. N., Novitski, E., Ondze, J. C. Nzobadila, O'Donnell, T., Gann, G. D. Orebi, Orrell, J. L., Ouellet, J. L., Parno, D. S., Paschke, K. D., Pastore, S., Pattie Jr, R. W., Petrov, A. A., Pitt, M. L., Plaster, B., Pocanic, D., Pocar, A., Poon, A. W. P., Radford, D. C., Rahangdale, H., Rasco, B. C., Rasiwala, H., Redwine, R. P., Ritz, A., Rogers, L., Ron, G., Saldanha, R., Sangiorgio, S., Sargsyan, G. H., Saunders, A., Savard, G., Schaper, D. C., Scholberg, K., Scielzo, N. D., Seng, C. -Y., Shindler, A., Singh, J. T., Singh, M., Singh, V., Snow, W. M., Soma, A. K., Souder, P. A., Speller, D. H., Stachurska, J., Surukuchi, P. T., Oregui, B. Tapia, Tomalak, O., Torres, J. A., Tyuka, O. A., VanDevender, B. A., Varriano, L., Vogt, R., Walker-Loud, A., Wamba, K., Watkins, S. L., Wietfeldt, F. E., Williams, W. D., Wilson, J. T., Winslow, L., Yan, X. L., Yang, L., Young, A. R., Zheng, X., and Zhou, Y.
Subjects: Nuclear Experiment, Nuclear Theory
Abstract: This whitepaper presents the research priorities decided on by attendees of the 2022 Town Meeting for Fundamental Symmetries, Neutrons and Neutrinos, which took place December 13-15, 2022 in Chapel Hill, NC, as part of the Nuclear Science Advisory Committee (NSAC) 2023 Long Range Planning process. A total of 275 scientists registered for the meeting. The whitepaper makes a number of explicit recommendations and justifies them in detail.
Published: 2023

2. 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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3. 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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4. 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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5. 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

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

Author: Christy, ME, Gautam, T, Ou, L, Schmookler, B, Wang, Y, Adikaram, D, Ahmed, Z, Albataineh, H, Ali, SF, Aljawrneh, B, Allada, K, Allison, SL, 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, CM, Campbell, J, Camsonne, A, Carmignotto, M, Castellanos, J, Chen, C, Chen, J-P, Chetry, T, Cisbani, E, Clary, B, Cohen, E, Compton, N, Cornejo, JC, 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, AV, Gray, VM, Gu, C, Habarakada, A, Hague, T, Hamad, G, Hamilton, D, Hamilton, K, Hansen, O, Hauenstein, F, Hernandez, AV, Henry, W, Higinbotham, DW, Holmstrom, T, Horn, T, Huang, Y, Huber, GM, Hyde, C, Ibrahim, H, Israel, N, Jen, C-M, Jin, K, Jones, M, Kabir, A, Karki, B, Keppel, C, Khachatryan, V, King, PM, Li, S, Li, W, Liu, H, Liu, J, Liyanage, AH, Mack, D, and Magee, J
Subjects: Nuclear and Plasma Physics, Particle and High Energy Physics, Physical Sciences, Mathematical Sciences, Engineering, General Physics, Mathematical sciences, Physical sciences
Abstract: We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q^{2}) up to 15.75 (GeV/c)^{2}. 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 or 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}.
Published: 2022

8. 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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9. 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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10. 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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11. 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

12. 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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13. 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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14. 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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15. An experimental program with high duty-cycle polarized and unpolarized positron beams at Jefferson Lab

Author: Accardi, A, Afanasev, A, Albayrak, I, Ali, SF, Amaryan, M, Annand, JRM, 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, VV, Bernauer, JC, Bertone, V, Bianconi, A, Biselli, A, Bisio, P, Blunden, P, Boer, M, Bondì, M, Brinkmann, K-T, Briscoe, WJ, 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, PL, 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, El Fassi, L, Elouadrhiri, L, Ent, R, Erler, J, Fernando, IP, 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, Grauvogel, GN, Gueye, P, Guidal, M, Habet, S, Hague, TJ, Hamilton, DJ, Hansen, O, Hasell, D, Hattawy, M, Higinbotham, DW, Hobart, A, Horn, T, Hyde, CE, Ibrahim, H, Ilyichev, A, Italiano, A, Joo, K, Joosten, SJ, Khachatryan, V, Kalantarians, N, and Kalicy, G
Subjects: Nuclear and Plasma Physics, Particle and High Energy Physics, Synchrotrons and Accelerators, Physical Sciences, Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics, Nuclear and plasma physics, Particle and high energy physics, Synchrotrons and accelerators
Abstract: Positron beams, both polarized and unpolarized, are identified as important 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 of the energy-momentum tensor. 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.
Published: 2021

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

Author: Christy, ME, Gautam, T, Ou, L, Schmookler, B, Wang, Y, Adikaram, D, Ahmed, Z, Albataineh, H, Ali, SF, Aljawrneh, B, Allada, K, Allison, SL, 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, CM, Campbell, J, Camsonne, A, Carmignotto, M, Castellanos, J, Chen, C, Chen, J-P, Chetry, T, Cisbani, E, Clary, B, Cohen, E, Compton, N, Cornejo, JC, 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, AV, Gray, VM, Gu, C, Habarakada, A, Hague, T, Hamad, G, Hamilton, D, Hamilton, K, Hansen, O, Hauenstein, F, Hernandez, AV, Henry, W, Higinbotham, DW, Holmstrom, T, Horn, T, Huang, Y, Huber, GM, Hyde, C, Ibrahim, H, Israel, N, Jen, C-M, Jin, K, Jones, M, Kabir, A, Karki, B, Keppel, C, Khachatryan, V, King, PM, Li, S, Li, W, Liu, H, Liu, J, Liyanage, AH, Mack, D, and Magee, J
Subjects: nucl-ex, hep-ex
Abstract: We present new precision measurements of the elastic electron-protonscattering cross section for momentum transfer (Q$^2$) up to 15.75~\gevsq.Combined with existing data, these provide an improved extraction of the protonmagnetic form factor at high Q$^2$ and double the range over which alongitudinal/transverse separation of the cross section can be performed. Thedifference between our results and polarization data agrees with that observedat 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 isestablished at $>$95\% confidence. We use the discrepancy to quantify the sizeof TPE contributions needed to explain the cross section at high Q$^2$.
Published: 2021

17. 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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18. 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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19. 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

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

Author: Accardi, A, Afanasev, A, Albayrak, I, Ali, SF, Amaryan, M, Annand, JRM, 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, VV, Bernauer, JC, Bertone, V, Bianconi, A, Biselli, A, Bisio, P, Blunden, P, Boer, M, Bondì, M, Brinkmann, K-T, Briscoe, WJ, 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, PL, Contalbrigo, M, Costantini, G, D'Angelo, A, Darmé, L, Day, D, Defurne, M, Napoli, M De, Deur, A, Vita, R De, 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, IP, 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, GN, Gueye, P, Guidal, M, Habet, S, Hague, TJ, Hamilton, DJ, Hansen, O, Hasell, D, Hattawy, M, Higinbotham, DW, Hobart, A, Horn, T, Hyde, CE, Ibrahim, H, Ilyichev, A, Italiano, A, Joo, K, Joosten, SJ, Khachatryan, V, Kalantarians, N, and Kalicy, G
Subjects: nucl-ex, hep-ex, hep-ph
Abstract: Positron beams, both polarized and unpolarized, are identified as essentialingredients for the experimental programs at the next generation of leptonaccelerators. In the context of the hadronic physics program at Jefferson Lab(JLab), positron beams are complementary, even essential, tools for a preciseunderstanding of the electromagnetic structure of nucleons and nuclei, in boththe elastic and deep-inelastic regimes. For instance, elastic scattering ofpolarized and unpolarized electrons and positrons from the nucleon enables amodel independent determination of its electromagnetic form factors. Also, thedeeply-virtual scattering of polarized and unpolarized electrons and positronsallows unambiguous separation of the different contributions to the crosssection of the lepto-production of photons and of lepton-pairs, enabling anaccurate determination of the nucleons and nuclei generalized partondistributions, and providing an access to the gravitational form factors.Furthermore, positron beams offer the possibility of alternative tests of theStandard Model of particle physics through the search of a dark photon, theprecise measurement of electroweak couplings, and the investigation of chargedlepton flavor violation. This document discusses the perspectives of anexperimental program with high duty-cycle positron beams at JLab.
Published: 2020

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

Author: Magee, J. A., Narayan, A., Jones, D., Beminiwattha, R., Cornejo, J. C., Dalton, M. M., Deconinck, W., Dutta, D., Gaskell, D., Martin, J. W., Paschke, K. D., Tvaskis, V., Asaturyan, A., Benesch, J., Cates, G., Cavness, B. S., Dillon-Townes, L. A., Hays, G., Hoskins, J., Ihloff, E., Jones, R., King, P. M., Kowalski, S., Kurchaninov, L., Lee, L., McCreary, A., McDonald, M., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Nelyubin, V., Page, S., Ramsay, W. D., Solvignon, P., Storey, D., Tobias, W. A., Urban, E., Vidal, C., Waidyawansa, B., Wang, P., and Zhamkotchyan, S.
Subjects: Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract: We have performed a novel comparison between electron-beam polarimeters based on M{\o}ller and Compton scattering. A sequence of electron-beam polarization measurements were performed at low beam currents ($<$ 5 $\mu$A) during the $Q_{\rm weak}$ experiment in Hall C at Jefferson Lab. These low current measurements were bracketed by the regular high current (180 $\mu$A) operation of the Compton polarimeter. All measurements were found to be consistent within experimental uncertainties of 1% or less, demonstrating that electron polarization does not depend significantly on the beam current. This result lends confidence to the common practice of applying M{\o}ller measurements made at low beam currents to physics experiments performed at higher beam currents. The agreement between two polarimetry techniques based on independent physical processes sets an important benchmark for future precision asymmetry measurements that require sub-1% precision in polarimetry.
Published: 2016
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22. Measurement of Parity-Violating Asymmetry in Electron-Deuteron Inelastic Scattering

Author: Wang, D., Pan, K., Subedi, R., Ahmed, Z., Allada, K., Aniol, K. A., Armstrong, D. S., Arrington, J., Bellini, V., Beminiwattha, R., Benesch, J., Benmokhtar, F., Bertozzi, W., Camsonne, A., Canan, M., Cates, G. D., Chen, J. -P., Chudakov, E., Cisbani, E., Dalton, M. M., de Jager, C. W., De Leo, R., Deconinck, W., Deng, X., Deur, A., Dutta, C., Fassi, L. El, Erler, J., Flay, D., Franklin, G. B., Friend, M., Frullani, S., Garibaldi, F., Gilad, S., Giusa, A., Glamazdin, A., Golge, S., Grimm, K., Hafidi, K., Hansen, J. -O., Higinbotham, D. W., Holmes, R., Holmstrom, T., Holt, R. J., Huang, J., Hyde, C. E., Jen, C. M., Jones, D., Kang, Hoyoung, King, P. M., Kowalski, S., Kumar, K. S., Lee, J. H., LeRose, J. J., Liyanage, N., Long, E., McNulty, D., Margaziotis, D. J., Meddi, F., Meekins, D. G., Mercado, L., Meziani, Z. -E., Michaels, R., Mihovilovic, M., Muangma, N., Mesick, K. E., Nanda, S., Narayan, A., Nelyubin, V., Nuruzzaman, A., Oh, Y., Parno, D., Paschke, K. D., Phillips, S. K., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Rider, K., Riordan, S., Roche, J., Rubin, J., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Širca, S., Souder, P. A., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Urciuoli, G. M., Waidyawansa, B., Wojtsekhowski, B., Ye, L., Zhao, B., and Zheng, X.
Subjects: Nuclear Experiment, High Energy Physics - Experiment, High Energy Physics - Phenomenology
Abstract: The parity-violating asymmetries between a longitudinally-polarized electron beam and an unpolarized deuterium target have been measured recently. The measurement covered two kinematic points in the deep inelastic scattering region and five in the nucleon resonance region. We provide here details of the experimental setup, data analysis, and results on all asymmetry measurements including parity-violating electron asymmetries and those of inclusive pion production and beam-normal asymmetries. The parity-violating deep-inelastic asymmetries were used to extract the electron-quark weak effective couplings, and the resonance asymmetries provided the first evidence for quark-hadron duality in electroweak observables. These electron asymmetries and their interpretation were published earlier, but are presented here in more detail., Comment: 50 pages, submitted to Phys. Rev. C
Published: 2014
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23. 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

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

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

25. Early Results from the Qweak Experiment

Author: Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T., Balewski, J., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cates, G. D., Cornejo, J. C., Covrig, S., 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., Gaskel, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Johnston, K., 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., McHugh, M. J., Meekins, D., Mei, J., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Myers, 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., 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., and Zhamkochyan, S.
Subjects: Nuclear Experiment
Abstract: A subset of results from the recently completed Jefferson Lab Qweak experiment are reported. This experiment, sensitive to physics beyond the Standard Model, exploits the small parity-violating asymmetry in elastic ep scattering to provide the first determination of the protons weak charge Qweak(p). The experiment employed a 180 uA longitudinally polarized 1.16 GeV electron beam on a 35 cm long liquid hydrogen target. Scattered electrons corresponding to Q2 of 0.025 GeV2 were detected in eight Cerenkov detectors arrayed symmetrically around the beam axis. The goals of the experiment were to provide a measure of Qweak(p) to 4.2 percent (combined statistical and systematic error), which implies a measure of sin2(thetaw) at the level of 0.3 percent, and to help constrain the vector weak quark charges C1u and C1d. The experimental method is described, with particular focus on the challenges associated with the worlds highest power LH2 target. The new constraints on C1u and C1d provided by the subset of the experiments data analyzed to date will also be shown, together with the extracted weak charge of the neutron., Comment: 8 pages, 4 figures, INPC2013
Published: 2013
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26. First Determination of the Weak Charge of the Proton

Author: Qweak Collaboration, Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T., Balewski, J., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cates, G. D., Cornejo, J. C., Covrig, S., 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., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Johnston, K., 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., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Myers, 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., 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., and Zhamkochyan, S.
Subjects: Nuclear Experiment
Abstract: The Qweak experiment has measured the parity-violating asymmetry in polarized e-p elastic scattering at Q^2 = 0.025(GeV/c)^2, employing 145 microamps of 89% longitudinally polarized electrons on a 34.4cm long liquid hydrogen target at Jefferson Lab. The results of the experiment's commissioning run are reported here, constituting approximately 4% of the data collected in the experiment. From these initial results the measured asymmetry is Aep = -279 +- 35 (statistics) +- 31 (systematics) ppb, which is the smallest and most precise asymmetry ever measured in polarized e-p scattering. The small Q^2 of this experiment has made possible the first determination of the weak charge of the proton, QpW, by incorporating earlier parity-violating electron scattering (PVES) data at higher Q^2 to constrain hadronic corrections. The value of QpW obtained in this way is QpW(PVES) = 0.064 +- 0.012, in good agreement with the Standard Model prediction of QpW(SM) = 0.0710 +- 0.0007. When this result is further combined with the Cs atomic parity violation (APV) measurement, significant constraints on the weak charges of the up and down quarks can also be extracted. That PVES+APV analysis reveals the neutron's weak charge to be QnW(PVES+APV) = -0.975 +- 0.010., Comment: 7 pages, 3 figures
Published: 2013
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27. Measurement of the Parity-Violating Asymmetry in Electron-Deuteron Scattering in the Nucleon Resonance Region

Author: Wang, D., Pan, K., Subedi, R., Deng, X., Ahmed, Z., Allada, K., Aniol, K. A., Armstrong, D. S., Arrington, J., Bellini, V., Beminiwattha, R., Benesch, J., Benmokhtar, F., Camsonne, A., Canan, M., Cates, G. D., Chen, J. -P., Chudakov, E., Cisbani, E., Dalton, M. M., de Jager, C. W., De Leo, R., Deconinck, W., Deur, A., Dutta, C., Fassi, L. El, Flay, D., Franklin, G. B., Friend, M., Frullani, S., Garibaldi, F., Giusa, A., Glamazdin, A., Golge, S., Grimm, K., Hafidi, K., Hansen, O., Higinbotham, D. W., Holmes, R., Holmstrom, T., Holt, R. J., Huang, J., Hyde, C. E., Jen, C. M., Jones, D., Kang, H., King, P., Kowalski, S., Kumar, K. S., Lee, J. H., LeRose, J. J., Liyanage, N., Long, E., McNulty, D., Margaziotis, D. J., Meddi, F., Meekins, D. G., Mercado, L., Meziani, Z. -E., Michaels, R., Mihovilovic, M., Muangma, N., Myers, K. E., Nanda, S., Narayan, A., Nelyubin, V., Nuruzzaman, Oh, Y., Parno, D., Paschke, K. D., Phillips, S. K., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Rider, K., Riordan, S., Roche, J., Rubin, J., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Sirca, S., Souder, P. A., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Urciuoli, G. M., Waidyawansa, B., Wojtsekhowski, B., Ye, L., Zhao, B., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: We report on parity-violating asymmetries in the nucleon resonance region measured using $5 - 6$ GeV longitudinally polarized electrons scattering off an unpolarized deuterium target. These results are the first parity-violating asymmetry data in the resonance region beyond the $\Delta(1232)$, and provide a verification of quark-hadron duality in the nucleon electroweak $\gamma Z$ interference structure functions at the (10-15)% level. The results are of particular interest to models relevant for calculating the $\gamma Z$ box-diagram corrections to elastic parity-violating electron scattering measurements., Comment: 7 pages, 1 figure, to appear in Phys. Rev. Lett
Published: 2013
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28. New Measurements of the Transverse Beam Asymmetry for Elastic Electron Scattering from Selected Nuclei

Author: HAPPEX, The, Collaborations, PREX, Abrahamyan, S., Acha, A., Afanasev, A., Ahmed, Z., Albataineh, H., Aniol, K., Armstrong, D. S., Armstrong, W., Arrington, J., Averett, T., Babineau, B., Bailey, S. L., Barber, J., Barbieri, A., Beck, A., Bellini, V., Beminiwattha, R., Benaoum, H., Benesch, J., Benmokhtar, F., Bertin, P., Bielarski, T., Boeglin, W., Bosted, P., Butaru, F., Burtin, E., Cahoon, J., Camsonne, A., Canan, M., Carter, P., Chang, C. C., Cates, G. D., Chao, Y. C., Chen, C., Chen, J. P., Choi, Seonho, Chudakov, E., Cisbani, E., Craver, B., Cusanno, F., Dalton, M. M., De Leo, R., de Jager, K., Deconinck, W., Decowski, P., Deepa, D., Deng, X., Deur, A., Dutta, D., Etile, A., Ferdi, C., Feuerbach, R. J., Finn, J. M., Flay, D., Franklin, G. B., Friend, M., Frullani, S., Fuchey, E., Fuchs, S. A., Fuoti, K., Garibaldi, F., Gasser, E., Gilman, R., Giusa, A., Glamazdin, A., Glesener, L. E., Gomez, J., Gorchtein, M., Grames, J., Grimm, K., Gu, C., Hansen, O., Hansknecht, J., Hen, O., Higinbotham, D. W., Holmes, R. S., Holmstrom, T., Horowitz, C. J., Hoskins, J., Huang, J., Humensky, T. B., Hyde, C. E., Ibrahim, H., Itard, F., Jen, C. M., Jensen, E., Jiang, X., Jin, G., Johnston, S., Katich, J., Kaufman, L. J., Kelleher, A., Kliakhandler, K., King, P. M., Kolarkar, A., Kowalski, S., Kuchina, E., Kumar, K. S., Lagamba, L., Lambert, D., LaViolette, P., Leacock, J., Leckey IV, J., Lee, J. H., LeRose, J. J., Lhuillier, D., Lindgren, R., Liyanage, N., Lubinsky, N., Mammei, J., Mammoliti, F., Margaziotis, D. J., Markowitz, P., Mazouz, M., McCormick, K., McCreary, A., McNulty, D., Meekins, D. G., Mercado, L., Meziani, Z. E., Michaels, R. W., Mihovilovic, M., Moffit, B., Monaghan, P., Muangma, N., Munoz-Camacho, C., Nanda, S., Nelyubin, V., Neyret, D., Nuruzzaman, Oh, Y., Otis, K., Palmer, A., Parno, D., Paschke, K. D., Phillips, S. K., Poelker, M., Pomatsalyuk, R., Posik, M., Potokar, M., Prok, K., Puckett, A. J. R., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Reitz, B., Riordan, S., Roche, J., Rogan, P., Ron, G., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Singh, J., Sirca, S., Slifer, K., Snyder, R., Solvignon, P., Souder, P. A., Sperduto, M. L., Subedi, R., Stutzman, M. L., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Troth, W., Urciuoli, G. M., Ulmer, P., Vacheret, A., Voutier, E., Waidyawansa, B., Wang, D., Wang, K., Wexler, J., Whitbeck, A., Wilson, R., Wojtsekhowski, B., Yan, X., Yao, H., Ye, Y., Ye, Z., Yim, V., Zana, L., Zhan, X., Zhang, J., Zhang, Y., Zheng, X., Ziskin, V., and Zhu, P.
Subjects: Nuclear Experiment
Abstract: We have measured the beam-normal single-spin asymmetry $A_n$ in the elastic scattering of 1-3 GeV transversely polarized electrons from $^1$H and for the first time from $^4$He, $^{12}$C, and $^{208}$Pb. For $^1$H, $^4$He and $^{12}$C, the measurements are in agreement with calculations that relate $A_n$ to the imaginary part of the two-photon exchange amplitude including inelastic intermediate states. Surprisingly, the $^{208}$Pb result is significantly smaller than the corresponding prediction using the same formalism. These results suggest that a systematic set of new $A_n$ measurements might emerge as a new and sensitive probe of the structure of heavy nuclei., Comment: 5 pages, 3 figures, accepted by PRL. v3: fixed one author name and affiliation, otherwise no change
Published: 2012
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29. Measurement of the Neutron Radius of 208Pb Through Parity-Violation in Electron Scattering

Author: Abrahamyan, S., Ahmed, Z., Albataineh, H., Aniol, K., Armstrong, D. S., Armstrong, W., Averett, T., Babineau, B., Barbieri, A., Bellini, V., Beminiwattha, R., Benesch, J., Benmokhtar, F., Bielarski, T., Boeglin, W., Camsonne, A., Canan, M., Carter, P., Cates, G. D., Chen, C., Chen, J. -P., Hen, O., Cusanno, F., Dalton, M. M., De Leo, R., de Jager, K., Deconinck, W., Decowski, P., Deng, X., Deur, A., Dutta, D., Etile, A., Flay, D., Franklin, G. B., Friend, M., Frullani, S., Fuchey, E., Garibaldi, F., Gasser, E., Gilman, R., Giusa, A., Glamazdin, A., Gomez, J., Grames, J., Gu, C., Hansen, O., Hansknecht, J., Higinbotham, D. W., Holmes, R. S., Holmstrom, T., Horowitz, C. J., Hoskins, J., Huang, J., Hyde, C. E., Itard, F., Jen, C. -M., Jensen, E., Jin, G., Johnston, S., Kelleher, A., Kliakhandler, K., King, P. M., Kowalski, S., Kumar, K. S., Leacock, J., Leckey IV, J., Lee, J. H., LeRose, J. J., Lindgren, R., Liyanage, N., Lubinsky, N., Mammei, J., Mammoliti, F., Margaziotis, D. J., Markowitz, P., McCreary, A., McNulty, D., Mercado, L., Meziani, Z. -E., Michaels, R. W., Mihovilovic, M., Muangma, N., Muñoz-Camacho, C., Nanda, S., Nelyubin, V., Nuruzzaman, N., Oh, Y., Palmer, A., Parno, D., Paschke, K. D., Phillips, S. K., Poelker, B., Pomatsalyuk, R., Posik, M., Puckett, A. J. R., Quinn, B., Rakhman, A., Reimer, P. E., Riordan, S., Rogan, P., Ron, G., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Sirca, S., Slifer, K., Solvignon, P., Souder, P. A., Sperduto, M. L., Subedi, R., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Troth, W., Urciuoli, G. M., Waidyawansa, B., Wang, D., Wexler, J., Wilson, R., Wojtsekhowski, B., Yan, X., Yao, H., Ye, Y., Ye, Z., Yim, V., Zana, L., Zhan, X., Zhang, J., Zhang, Y., Zheng, X., and Zhu, P.
Subjects: Nuclear Experiment
Abstract: We report the first measurement of the parity-violating asymmetry A_PV in the elastic scattering of polarized electrons from 208Pb. A_PV is sensitive to the radius of the neutron distribution (Rn). The result A_PV = 0.656 \pm 0.060 (stat) \pm 0.014 (syst) ppm corresponds to a difference between the radii of the neutron and proton distributions Rn - Rp = 0.33 +0.16 -0.18 fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus., Comment: 6 pages, 1 figure
Published: 2012
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30. New Precision Limit on the Strange Vector Form Factors of the Proton

Author: HAPPEX collaboration, Ahmed, Z., Allada, K., Aniol, K. A., Armstrong, D. S., Arrington, J., Baturin, P., Bellini, V., Benesch, J., Beminiwattha, R., Benmokhtar, F., Canan, M., Camsonne, A., Cates, G. D., Chen, J. -P., Chudakov, E., Cisbani, E., Dalton, M. M., de Jager, C. W., De Leo, R., Deconinck, W., Decowski, P., Deng, X., Deur, A., Dutta, C., Franklin, G. B., Friend, M., Frullani, S., Garibaldi, F., Giusa, A., Glamazdin, A., Golge, S., Grimm, K., Hansen, O., Higinbotham, D. W., Holmes, R., Holmstrom, T., Huang, J., Huang, M., Hyde, C. E., Jen, C. M., Jin, G., Jones, D., Kang, H., King, P., Kowalski, S., Kumar, K. S., Lee, J. H., LeRose, J. J., Liyanage, N., Long, E., McNulty, D., Margaziotis, D., Meddi, F., Meekins, D. G., Mercado, L., Meziani, Z. -E., Michaels, R., Munoz-Camacho, C., Mihovilovic, M., Muangma, N., Myers, K. E., Nanda, S., Narayan, A., Nelyubin, V., Nuruzzaman, Oh, Y., Pan, K., Parno, D., Paschke, K. D., Phillips, S. K., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Rider, K., Riordan, S., Roche, J., Rubin, J., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Silwal, R., Sirca, S., Souder, P. A., Sperduto, M., Subedi, R., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Urciuoli, G. M., Waidyawansa, B., Wang, D., Wexler, J., Wilson, R., Wojtsekhowski, B., Zhan, X., Yan, X., Yao, H., Ye, L., Zhao, B., and Zheng, X.
Subjects: Nuclear Experiment
Abstract: The parity-violating cross-section asymmetry in the elastic scattering of polarized electrons from unpolarized protons has been measured at a four-momentum transfer squared Q2 = 0.624 GeV and beam energy E =3.48 GeV to be A_PV = -23.80 +/- 0.78 (stat) +/- 0.36 (syst) parts per million. This result is consistent with zero contribution of strange quarks to the combination of electric and magnetic form factors G_E^s + 0.517 G_M^s = 0.003 +/- 0.010 (stat) +/- 0.004 (syst) +/- 0.009 (ff), where the third error is due to the limits of precision on the electromagnetic form factors and radiative corrections. With this measurement, the world data on strange contributions to nucleon form factors are seen to be consistent with zero and not more than a few percent of the proton form factors., Comment: 5 pages, 3 figures
Published: 2011
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31. The tracking analysis in the Q-weak experiment

Author: Pan, J., Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T., Balewski, J., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cates, G. D., Cornejo, J. C., Covrig, S., 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., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Johnston, K., 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., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Myers, 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., 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., and Zhamkochyan, S.
Published: 2016
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32. 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: General Physics and Astronomy, FOS: Physical sciences, Nuclear Experiment (nucl-ex), single spin asymmetry, elastic electron scattering, 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: 2022

33. 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, John, Arrington, J., Atac, H., Averett, T., Ayerbe Gayoso, C., 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., Covrig Dusa, S., 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, David, 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, Rachel, 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., Reimer, P.E., Riordan, S., Roche, J., Sapkota, I., Sarty, A., Sawatzky, B., Saylor, N.H., Shabestari, M.H., Shahinyan, A., Širca, 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., Zhu, P., Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), CentraleSupélec, and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)
Subjects: exchange: two-photon, polarization, longitudinal, momentum transfer, p: form factor: magnetic, FOS: Physical sciences, General Physics and Astronomy, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], form factor, electron-proton scattering, two photon exchange, High Energy Physics - Experiment, electron p: scattering, High Energy Physics - Experiment (hep-ex), transverse, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Experiment (nucl-ex), cross section: elastic scattering, Nuclear 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$., 7 pages, 2 figures
Published: 2022

34. Determination of the ^{27}Al Neutron Distribution Radius from a Parity-Violating Electron Scattering Measurement

Author: Androić, Darko, Armstrong, D. S., Bartlett, K., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cornejo, J. C., Covrig Dusa, S., Dalton, M. M., Davis, C. A., Deconinck, W., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Elaasar, M., Falk, W. R., Finn, J. M., 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., 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., Ševa, Tomislav, Shabestari, M. H., Silwal, R., Šimičević, Neven, Smith, G. R., Solvignon, P., Spayde, D. T., Subedi, A., 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: parity vialation, elastic electron scattering asimmetry, neuton skin thickness
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.
Published: 2021

35. The ${Q^{p}_{\rm Weak}}$ experiment: A search for physics beyond the standard model via a measurement of the proton’s weak charge

Author: Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T., Balewski, J., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cornejo, J. C., Covrig, S., Dalton, M. M., Davis, C. A., Deconinck, W., Diefenbach, J., Dow, K., Dowd, J. F., Dunne, J. A., Dutta, D., Duvall, W. S., Elaasar, M., Falk, W. R., Finn, J. M., Forest, T., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Johnston, K., 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., McHugh, M., Meekins, D., Mei, J., Michaels, R., Micherdzinska, A., Myers, K. E., Mkrtchyan, A., Mkrtchyan, H., Narayan, A., Ndukum, L. Z., Nelyubin, V., Nuruzzaman, N., van Oers, W. T. H, Opper, A. K., Page, S. A., Pan, J., Paschke, K., 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., 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., Zhamkochyan, S., and Zou, D.
Published: 2013
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36. Deep Exclusive Electroproduction of π0 at High Q2 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., Zhu, P., Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Jefferson Lab Hall A
Subjects: [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], momentum transfer dependence, helicity, High Energy Physics - Experiment, pi: distribution amplitude, generalized parton distribution: transversity, kinematics, pi0: electroproduction, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], quark: valence, polarization: transverse, High Energy Physics::Experiment, p: structure function, Nuclear Experiment, experimental results, photon: virtual, Jefferson Lab
Abstract: International audience; We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of xB (0.36, 0.48, and 0.60) and Q2 (3.1 to 8.4 GeV2) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσT/dt+εdσL/dt, dσTT/dt, dσLT/dt, and dσLT′/dt are extracted as a function of the proton momentum transfer t-tmin. 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

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

Author: Massachusetts Institute of Technology. Department of Physics, Massachusetts Institute of Technology. Laboratory for Nuclear Science, 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. A., Bai, X., Barion, L., Battaglieri, M., Bellini, V., Beminiwattha, R., Benmokhtar, F., Berdnikov, V. V., Bernauer, J. C., Massachusetts Institute of Technology. Department of Physics, Massachusetts Institute of Technology. Laboratory for Nuclear Science, 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. A., Bai, X., Barion, L., Battaglieri, M., Bellini, V., Beminiwattha, R., Benmokhtar, F., Berdnikov, V. V., and Bernauer, J. C.
Abstract: Positron beams, both polarized and unpolarized, are identified as important 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 of the energy-momentum tensor. 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.
Published: 2021

38. Measurement of parity violation in electron–quark scattering

Author: Wang, D., Pan, K., Subedi, R., Deng, X., Ahmed, Z., Allada, K., Aniol, K. A., Armstrong, D. S., Arrington, J., Bellini, V., Beminiwattha, R., Benesch, J., Benmokhtar, F., Bertozzi, W., Camsonne, A., Canan, M., Cates, G. D., Chen, J.-P., Chudakov, E., Cisbani, E., Dalton, M. M., de Jager, C. W., De Leo, R., Deconinck, W., Deur, A., Dutta, C., El Fassi, L., Erler, J., Flay, D., Franklin, G. B., Friend, M., Frullani, S., Garibaldi, F., Gilad, S., Giusa, A., Glamazdin, A., Golge, S., Grimm, K., Hafidi, K., Hansen, J.-O., Higinbotham, D. W., Holmes, R., Holmstrom, T., Holt, R. J., Huang, J., Hyde, C. E., Jen, C. M., Jones, D., Kang, Hoyoung, King, P. M., Kowalski, S., Kumar, K. S., Lee, J. H., LeRose, J. J., Liyanage, N., Long, E., McNulty, D., Margaziotis, D. J., Meddi, F., Meekins, D. G., Mercado, L., Meziani, Z.-E., Michaels, R., Mihovilovic, M., Muangma, N., Myers, K. E., Nanda, S., Narayan, A., Nelyubin, V., Nuruzzaman, Oh, Y., Parno, D., Paschke, K. D., Phillips, S. K., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Rider, K., Riordan, S., Roche, J., Rubin, J., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Sirca, S., Souder, P. A., Suleiman, R., Sulkosky, V., Sutera, C. M., Tobias, W. A., Urciuoli, G. M., Waidyawansa, B., Wojtsekhowski, B., Ye, L., Zhao, B., and Zheng, X.
Published: 2014
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39. Parity-violating inelastic electron-proton scattering at low Q2 above the resonance region

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

40. The ${Q^{p}_{\rm Weak}}$ experiment

Author: Androic, D., primary, Armstrong, D. S., additional, Asaturyan, A., additional, Averett, T., additional, Balewski, J., additional, Beaufait, J., additional, Beminiwattha, R. S., additional, Benesch, J., additional, Benmokhtar, F., additional, Birchall, J., additional, Carlini, R. D., additional, Cornejo, J. C., additional, Covrig, S., additional, Dalton, M. M., additional, Davis, C. A., additional, Deconinck, W., additional, Diefenbach, J., additional, Dow, K., additional, Dowd, J. F., additional, Dunne, J. A., additional, Dutta, D., additional, Duvall, W. S., additional, Elaasar, M., additional, Falk, W. R., additional, Finn, J. M., additional, Forest, T., additional, Gaskell, D., additional, Gericke, M. T. W., additional, Grames, J., additional, Gray, V. M., additional, Grimm, K., additional, Guo, F., additional, Hoskins, J. R., additional, Johnston, K., additional, Jones, D., additional, Jones, M., additional, Jones, R., additional, Kargiantoulakis, M., additional, King, P. M., additional, Korkmaz, E., additional, Kowalski, S., additional, Leacock, J., additional, Leckey, J., additional, Lee, A. R., additional, Lee, J. H., additional, Lee, L., additional, MacEwan, S., additional, Mack, D., additional, Magee, J. A., additional, Mahurin, R., additional, Mammei, J., additional, Martin, J., additional, McHugh, M., additional, Meekins, D., additional, Mei, J., additional, Michaels, R., additional, Micherdzinska, A., additional, Myers, K. E., additional, Mkrtchyan, A., additional, Mkrtchyan, H., additional, Narayan, A., additional, Ndukum, L. Z., additional, Nelyubin, V., additional, Nuruzzaman, N., additional, van Oers, W. T. H, additional, Opper, A. K., additional, Page, S. A., additional, Pan, J., additional, Paschke, K., additional, Phillips, S. K., additional, Pitt, M. L., additional, Poelker, M., additional, Rajotte, J. F., additional, Ramsay, W. D., additional, Roche, J., additional, Sawatzky, B., additional, Seva, T., additional, Shabestari, M. H., additional, Silwal, R., additional, Simicevic, N., additional, Smith, G., additional, Solvignon, P., additional, Spayde, D. T., additional, Subedi, A., additional, Subedi, R., additional, Suleiman, R., additional, Tadevosyan, V., additional, Tobias, W. A., additional, Tvaskis, V., additional, Waidyawansa, B., additional, Wang, P., additional, Wells, S. P., additional, Wood, S. A., additional, Yang, S., additional, Young, R. D., additional, Zhamkochyan, S., additional, and Zou, D., additional
Published: 2013
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41. A novel comparison of Møller and Compton electron-beam polarimeters

Author: Magee, J.A., Narayan, A., Jones, D., Beminiwattha, R., Cornejo, J.C., Dalton, M.M., Deconinck, W., Dutta, D., Gaskell, D., Martin, J.W., Paschke, K.D., Tvaskis, V., Asaturyan, A., Benesch, J., Cates, G., Cavness, B.S., A. Dillon-Townes, L., Hays, G., Hoskins, J., Ihloff, E., Jones, R., King, P.M., Kowalski, S., Kurchaninov, L., Lee, L., McCreary, A., McDonald, M., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Nelyubin, V., Page, S., Ramsay, W.D., Solvignon, P., Storey, D., Tobias, W.A., Urban, E., Vidal, C., Waidyawansa, B., Wang, P., and Zhamkotchyan, S.
Published: 2017
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42. First Direct Measurement of the Proton’s Weak Charge

Author: Androić, Darko, 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., Cates, G. D., Cornejo, J. C., Covrig, S., Dalton, M. M., Davis, C. A., Deconinck, W., Diefenbach, J., Dowd, J. F., Dunne, J. A., Dutta, D., Duvalla, 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., Johnston, K., 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., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Myers, K. E., Narayan, A., Ndukum, L. Z., Nelyubin, V., Nuhait, H., Nuruzzaman, W.T.H van Oers, Page, S. A., Opper, A. K., Pan, J., Paschke, K. D., Phillips, S. K., Pitt, M. L., Poelker, M., Rajotte, J. F., Ramsay, W. D., Roche, J., Sawatzky, B., Ševa, Tomislav, Shabestari, M. H., Silwal, R., Šimičević, Neven, 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: PRIRODNE ZNANOSTI. Fizika, q-weak experiment, Nuclear Experiment, NATURAL SCIENCES. Physics
Abstract: The Qweak experiment, which took data at Jefferson Lab in the period 2010 - 2012, will precisely determine the weak charge of the proton by measuring the parity-violating asymmetry in elastic e-p scattering at 1.1 GeV using a longitudinally polarized electron beam and a liquid hydrogen target at a low momentum transfer of Q2 = 0.025 (GeV/c)2. The weak charge of the proton is predicted by the Standard Model and any significant deviation would indicate physics beyond the Standard Model. The technical challenges and experimental apparatus for measuring the weak charge of the proton will be discussed, as well as the method of extracting the weak charge of the proton. The results from a small subset of the data, that has been published, will also be presented. Furthermore an update will be given of the current status of the data analysis.
Published: 2017

43. Measurement of the Spectral Function of 40Ar through the (e, e'p) reaction

Author: Ankowski, Artur M., Beminiwattha, R. S., Benhar, Omar, Crabb, D. G., Day, D. B., Garibaldi, F., Garvey, G. T., Gaskell, D., Giusti, C., Hansen, O., Higinbotham, D. W., Holmes, R., Jen, C. M., Jiang, X., Keller, D., Keppel, C. E., Lindgren, R., Link, Jonathan M., Liyanage, N., Mariani, Camillo, Meucci, A., Mills, G. B., Myers, L., Pitt, M. L., Rondon, O. A., Sakuda, M., Sawatzky, B., Souder, P. A., Urciuoli, G. M., Wood, S., Zhang, J., and Physics
Subjects: nucl-th, Physics::Instrumentation and Detectors, nucl-ex
Abstract: The interpretation of the signals detected by high precision experiments aimed at measuring neutrino oscillations requires an accurate description of the neutrino-nucleus cross sections. One of the key element of the analysis is the treatment of nuclear effects, which is one of the main sources of systematics for accelerator based experiments such as the Long Baseline Neutrino Experiment (LBNE). A considerable effort is currently being made to develop theoretical models capable of providing a fully quantitative description of the neutrino-nucleus cross sections in the kinematical regime relevant to LBNE. The approach based on nuclear many-body theory and the spectral function formalism has proved very successful in explaining the available electron scattering data in a variety of kinematical conditions. The first step towards its application to the analysis of neutrino data is the derivation of the spectral functions of nuclei employed in neutrino detectors, in particular argon. We propose a measurement of the coincidence (e, e'p) cross section on argon. This data will provide the experimental input indispensable to construct the argon spectral function, thus paving the way for a reliable estimate of the neutrino cross sections. In addition, the analysis of the (e, e'p) data will help a number of theoretical developments, like the description of final-state interactions needed to isolate the initial-state contributions to the observed single-particle peaks, that is also needed for the interpretation of the signal detected in neutrino experiments. 28 pages, 4 figures, Proposal PR12-14-012 submitted to the JLAB PAC 42, July 2014
Published: 2014

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

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

45. Measurement of parity-violating asymmetry in electron-deuteron inelastic scattering

Author: Massachusetts Institute of Technology. Department of Physics, Massachusetts Institute of Technology. Laboratory for Nuclear Science, Bertozzi, William, Deconinck, Wouter, Pan, Kai, Gilad, Shalev, Huang, Jin, Kowalski, Stanley B., Muangma, Navaphon, Sulkosky, Vincent, Wang, D., Subedi, R., Ahmed, Z., Allada, Kalyan C., Aniol, K., Armstrong, D. S., Arrington, J., Bellini, V., Beminiwattha, R., Benesch, J., Benmokhtar, F., Camsonne, A., Canan, M., Cates, G. D., Chen, J.-P., Chudakov, E., Cisbani, E., Dalton, M. M., de Jager, C. W., De Leo, R., Deng, X., Deur, A., Dutta, C., Fassi, L. El, Erler, J., Flay, D., Franklin, G. B., Friend, M., Frullani, S., Garibaldi, F., Giusa, A., Glamazdin, A., Golge, S., Grimm, K., Hafidi, K., Hansen, J.-O., Higinbotham, D. W., Holmes, R., Holmstrom, T., Holt, R. J., Hyde, C. E., Jen, C. M., Jones, D., Kang, Hoyoung, King, P. M., Kumar, K. S., Lee, J. H., LeRose, J. J., Liyanage, N., Long, E., McNulty, D., Margaziotis, D. J., Meddi, F., Meekins, D. G., Mercado, L., Meziani, Z.-E., Michaels, R., Mihovilovic, M., Mesick, K. E., Nanda, S., Narayan, A., Nelyubin, V., Nuruzzaman, N., Oh, Y., Parno, D., Paschke, K. D., Phillips, S. K., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Rider, K., Riordan, S., Roche, J., Rubin, J., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Širca, S., Souder, P. A., Suleiman, R., Sutera, C. M., Tobias, W. A., Urciuoli, G. M., Waidyawansa, B., Wojtsekhowski, B., Ye, L., Zhao, B., Zheng, X., Kowalski, Stanley B, Massachusetts Institute of Technology. Department of Physics, Massachusetts Institute of Technology. Laboratory for Nuclear Science, Bertozzi, William, Deconinck, Wouter, Pan, Kai, Gilad, Shalev, Huang, Jin, Kowalski, Stanley B., Muangma, Navaphon, Sulkosky, Vincent, Wang, D., Subedi, R., Ahmed, Z., Allada, Kalyan C., Aniol, K., Armstrong, D. S., Arrington, J., Bellini, V., Beminiwattha, R., Benesch, J., Benmokhtar, F., Camsonne, A., Canan, M., Cates, G. D., Chen, J.-P., Chudakov, E., Cisbani, E., Dalton, M. M., de Jager, C. W., De Leo, R., Deng, X., Deur, A., Dutta, C., Fassi, L. El, Erler, J., Flay, D., Franklin, G. B., Friend, M., Frullani, S., Garibaldi, F., Giusa, A., Glamazdin, A., Golge, S., Grimm, K., Hafidi, K., Hansen, J.-O., Higinbotham, D. W., Holmes, R., Holmstrom, T., Holt, R. J., Hyde, C. E., Jen, C. M., Jones, D., Kang, Hoyoung, King, P. M., Kumar, K. S., Lee, J. H., LeRose, J. J., Liyanage, N., Long, E., McNulty, D., Margaziotis, D. J., Meddi, F., Meekins, D. G., Mercado, L., Meziani, Z.-E., Michaels, R., Mihovilovic, M., Mesick, K. E., Nanda, S., Narayan, A., Nelyubin, V., Nuruzzaman, N., Oh, Y., Parno, D., Paschke, K. D., Phillips, S. K., Qian, X., Qiang, Y., Quinn, B., Rakhman, A., Reimer, P. E., Rider, K., Riordan, S., Roche, J., Rubin, J., Russo, G., Saenboonruang, K., Saha, A., Sawatzky, B., Shahinyan, A., Silwal, R., Širca, S., Souder, P. A., Suleiman, R., Sutera, C. M., Tobias, W. A., Urciuoli, G. M., Waidyawansa, B., Wojtsekhowski, B., Ye, L., Zhao, B., Zheng, X., and Kowalski, Stanley B
Abstract: The parity-violating asymmetries between a longitudinally polarized electron beam and an unpolarized deuterium target have been measured recently. The measurement covered two kinematic points in the deep-inelastic scattering region and five in the nucleon resonance region. We provide here details of the experimental setup, data analysis, and results on all asymmetry measurements including parity-violating electron asymmetries and those of inclusive pion production and beam-normal asymmetries. The parity-violating deep-inelastic asymmetries were used to extract the electron-quark weak effective couplings, and the resonance asymmetries provided the first evidence for quark-hadron duality in electroweak observables. These electron asymmetries and their interpretation were published earlier, but are presented here in more detail.
Published: 2015

46. Qweak: First Direct Measurement of the Proton's Weak Charge.

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., Cates, G. D., Cornejo, J. C., Covrig, S., Dalton, M. M., Davis, C. A., Deconinck, W., Diefenbach, J., and Dowd, J. F.
Subjects: PROTONS, ELASTIC scattering, MOMENTUM transfer, ELECTRON beams, LIQUID hydrogen
Abstract: The article presents an overview of the Qweak experiment which aimed to determine the weak charge of the proton QpW and discusses its results. Topics mentioned include measurement of the parity-violating asymmetry, the construction of the Qweak apparatus in Hall C at the Thomas Jefferson National Accelerator Facility, and the Qweak's liquid nitrogen target.
Published: 2017
Full Text: View/download PDF

47. The Q[superscript p][subscript Weak] experiment

Author: Androic, D., Armstrong, D. S, Asaturyan, A., Averett, T., Beaufait, J., Beminiwattha, R. S, Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D, Cornejo, J. C, Covrig, S., 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., Gaskell, D., Gericke, M. T W, Grames, J., Gray, V. M, Grimm, K., Hoskins, J. R, Johnston, K., Jones, D., Jones, M., Jones, R., Kargiantoulakis, M., King, P. M, Korkmaz, E., 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., McHugh, M., Meekins, D., Mei, J., Michaels, R., Micherdzinska, A., Myers, K. E, Mkrtchyan, A., Mkrtchyan, H., Narayan, A., Ndukum, L. Z, Nelyubin, V., Nuruzzaman, N., van Oers, W. T H, Opper, A. K, Page, S. A, Pan, J., Paschke, K., Phillips, S. K, Pitt, M. L, Poelker, M., Ramsay, W. D, Roche, J., Sawatzky, B., Seva, T., Shabestari, M. H, Silwal, R., Simicevic, N., Smith, G., 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, Zhamkochyan, S., Balewski, Jan T., Dow, Karen Ann, Guo, Fang, Kowalski, Stanley B, Rajotte, Jean-Francois, Zou, David, Massachusetts Institute of Technology. Department of Physics, Massachusetts Institute of Technology. Laboratory for Nuclear Science, Balewski, Jan T., Dow, Karen Ann, Guo, Fang, Kowalski, Stanley B, Rajotte, Jean-Francois, and Zou, David
Abstract: In May 2012, the Q[superscript p][subscript Weak] collaboration completed a two year measurement program to determine the weak charge of the proton Q[superscript p][subscript Weak] = ( 1 - 4sin [superscript 2] θ[subscript W] at the Thomas Jefferson National Accelerator Facility (TJNAF). The experiment was designed to produce a 4.0 % measurement of the weak charge, via a 2.5 % measurement of the parity violating asymmetry in the number of elastically scattered 1.165 GeV electrons from protons, at forward angles. At the proposed precision, the experiment would produce a 0.3 % measurement of the weak mixing angle at a momentum transfer of Q[superscript 2] = 0.026 GeV[superscript 2], making it the most precise stand alone measurement of the weak mixing angle at low momentum transfer. In combination with other parity measurements, Q[superscript p][subscript Weak] will also provide a high precision determination of the weak charges of the up and down quarks. At the proposed precision, a significant deviation from the Standard Model prediction could be a signal of new physics at mass scales up to ≃ 6 TeV, whereas agreement would place new and significant constraints on possible Standard Model extensions at mass scales up to ≃ 2 TeV. This paper provides an overview of the physics and the experiment, as well as a brief look at some preliminary diagnostic and analysis data.
Published: 2013

48. Measurement of the Neutron Radius of Pb-208 through Parity Violation in Electron Scattering

Author: Abrahamyan, S, Ahmed, Z, Albataineh, H, Aniol, K, Armstrong, Ds, Armstrong, W, Averett, T, Babineau, B, Barbieri, A, Bellini, Vincenzo, Beminiwattha, R, Benesch, J, Benmokhtar, F, Bielarski, T, Boeglin, W, Camsonne, A, Canan, M, Carter, P, Cates, Gd, Chen, C, Chen, Jp, Hen, O, Cusanno, F, Dalton, Mm, De, Le, R, de Jager, K, Deconinck, W, Decowski, P, Deng, X, Deur, A, Dutta, D, Etile, A, Flay, D, Franklin, Gb, Friend, M, Frullani, S, Fuchey, E, Garibaldi, F, Gasser, E, Gilman, R, Giusa, A, Glamazdin, A, Gomez, J, Grames, J, Gu, C, Hansen, O, Hansknecht, J, Higinbotham, Dw, Holmes, Rs, Holmstrom, T, Horowitz, Cj, Hoskins, J, Huang, J, Hyde, Ce, Itard, F, Jen, Cm, Jensen, E, Jin, G, Johnston, S, Kelleher, A, Kliakhandler, K, King, Pm, Kowalski, S, Kumar, Ks, Leacock, J, Leckey, J, Lee, Jh, Lerose, Jj, Lindgren, R, Liyanage, N, Lubinsky, N, Mammei, J, Mammoliti, Francesco, Margaziotis, Dj, Markowitz, P, Mccreary, A, Mcnulty, D, Mercado, L, Meziani, Ze, Michaels, Rw, Mihovilovic, M, Muangma, N, Munoz Camacho, C, Nanda, S, Nelyubin, V, Nuruzzaman, N, Oh, Y, Palmer, A, Parno, D, Paschke, Kd, Phillips, Sk, Poelker, B, Pomatsalyuk, R, Posik, M, Puckett, Ajr, Quinn, B, Rakhman, A, Reimer, Pe, Riordan, S, Rogan, P, Ron, G, Russo, Giuseppe, Saenboonruang, K, Saha, A, Sawatzky, B, Shahinyan, A, Silwal, R, Sirca, S, Slifer, K, Solvignon, P, Souder, Pa, Sperduto, Ml, Subedi, R, Suleiman, R, Sulkosky, V, Sutera, CONCETTA MARIA, Tobias, Wa, Troth, W, Urciuoli, Gm, Waidyawansa, B, Wang, D, Wexler, J, Wilson, R, Wojtsekhowski, B, Yan, X, Yao, H, Ye, Y, Ye, Z, Yim, V, Zana, L, Zhan, X, Zhang, J, Zhang, Y, Zheng, X, and PREX Collaboration, Zhu P.
Subjects: ELECTRON-SCATTERING, NUCLEI, DENSITIES
Published: 2012

49. Measurement of the Spectral Function of 40Ar through the (e, e'p) reaction

Author: Physics, Ankowski, Artur M., Beminiwattha, R. S., Benhar, Omar, Crabb, D. G., Day, D. B., Garibaldi, F., Garvey, G. T., Gaskell, D., Giusti, C., Hansen, O., Higinbotham, D. W., Holmes, R., Jen, C. M., Jiang, X., Keller, D., Keppel, C. E., Lindgren, R., Link, Jonathan M., Liyanage, N., Mariani, Camillo, Meucci, A., Mills, G. B., Myers, L., Pitt, M. L., Rondon, O. A., Sakuda, M., Sawatzky, B., Souder, P. A., Urciuoli, G. M., Wood, S., Zhang, J., Physics, Ankowski, Artur M., Beminiwattha, R. S., Benhar, Omar, Crabb, D. G., Day, D. B., Garibaldi, F., Garvey, G. T., Gaskell, D., Giusti, C., Hansen, O., Higinbotham, D. W., Holmes, R., Jen, C. M., Jiang, X., Keller, D., Keppel, C. E., Lindgren, R., Link, Jonathan M., Liyanage, N., Mariani, Camillo, Meucci, A., Mills, G. B., Myers, L., Pitt, M. L., Rondon, O. A., Sakuda, M., Sawatzky, B., Souder, P. A., Urciuoli, G. M., Wood, S., and Zhang, J.
Abstract: The interpretation of the signals detected by high precision experiments aimed at measuring neutrino oscillations requires an accurate description of the neutrino-nucleus cross sections. One of the key element of the analysis is the treatment of nuclear effects, which is one of the main sources of systematics for accelerator based experiments such as the Long Baseline Neutrino Experiment (LBNE). A considerable effort is currently being made to develop theoretical models capable of providing a fully quantitative description of the neutrino-nucleus cross sections in the kinematical regime relevant to LBNE. The approach based on nuclear many-body theory and the spectral function formalism has proved very successful in explaining the available electron scattering data in a variety of kinematical conditions. The first step towards its application to the analysis of neutrino data is the derivation of the spectral functions of nuclei employed in neutrino detectors, in particular argon. We propose a measurement of the coincidence (e, e'p) cross section on argon. This data will provide the experimental input indispensable to construct the argon spectral function, thus paving the way for a reliable estimate of the neutrino cross sections. In addition, the analysis of the (e, e'p) data will help a number of theoretical developments, like the description of final-state interactions needed to isolate the initial-state contributions to the observed single-particle peaks, that is also needed for the interpretation of the signal detected in neutrino experiments.
Published: 2014

50. First Determination of the Weak Charge of the Proton

Author: Physics, Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T., Balewski, J., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cates, G. D., Cornejo, J. C., Covrig, S., 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., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Johnston, K., Jones, D., Jones, M., Jones, R., Kargiantoulakis, M., King, P. M., Korkmaz, E., Kowalski, S., Leacock, John, 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., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Myers, 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., 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., Zhamkochyan, S., Physics, Androic, D., Armstrong, D. S., Asaturyan, A., Averett, T., Balewski, J., Beaufait, J., Beminiwattha, R. S., Benesch, J., Benmokhtar, F., Birchall, J., Carlini, R. D., Cates, G. D., Cornejo, J. C., Covrig, S., 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., Gaskell, D., Gericke, M. T. W., Grames, J., Gray, V. M., Grimm, K., Guo, F., Hoskins, J. R., Johnston, K., Jones, D., Jones, M., Jones, R., Kargiantoulakis, M., King, P. M., Korkmaz, E., Kowalski, S., Leacock, John, 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., Michaels, R., Micherdzinska, A., Mkrtchyan, A., Mkrtchyan, H., Morgan, N., Myers, 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., 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., and Zhamkochyan, S.
Published: 2013

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