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

Author: R. I. Pomatsalyuk, Yannick Rousseau, A. J. R. Puckett, C. E. Hyde, Ishay Pomerantz, A. P. Freyberger, M. Olson, A. Shahinyan, Kent Paschke, Karl Slifer, E. Piasetzky, S. Strauch, X. Jiang, Fatiha Benmokhtar, H. Arenaövel, A. T. Katramatou, J. R. Calarco, H. F. Ibrahim, T. Holmstrom, S. Frullani, Bryan J. Moffit, W.U. Boeglin, F. Cusanno, E. Chudakov, D. G. Meekins, Asghar Askarpour Kabir, Simon Širca, F. Garibaldi, M. H. Shabestari, Ronald Ransome, E. J. Brash, Guy Ron, Z. E. Meziani, R. Shneor, M. Potokar, Yordanka Ilieva, Young Do Oh, Xin Qian, E. Schulte, Whitney Armstrong, B. Craver, L. Coman, J. P. Chen, C. F. Perdrisat, A. J. Sarty, J.-O. Hansen, M. Reyhan, C. Dutta, B. E. Norum, B. Sawatzky, E. Kuchina, J. Dumas, Emily M. McCullough, Bumsung Lee, M. Meziane, J. Song, R. Michaels, B. L. Berman, G. G. Petratos, J. Roche, G. J. Kumbartzki, P. Giuliani, M. Schwamb, Smt Beck, Douglas Higinbotham, M. K. Jones, Ronald Gilman, Pete Markowitz, Michael Paolone, A. Adeyemi, A. Beck, Yujie Qiang, P. Solvignon, E. Khrosinkova, S. Choi, J. Arrington, Kalyan Allada, R. J. Feuerbach, Alexandre Camsonne, R. A. Lindgren, J. J. LeRose, Punjabi, Paul Gueye, A. Kelleher, and J. Glister
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, Hardware_MEMORYSTRUCTURES, medicine.anatomical_structure, Intermediate energy, Scattering, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, medicine, Elastic electron, Nuclear matter, Nucleus
Abstract: In the original PDF online version of this article, the references 22–26 were missing.These are the missing references.
Published: 2020
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2. Dispersive corrections in elastic electron-nucleus scattering: an investigation in the intermediate energy regime and their impact on the nuclear matter

Author: L. Coman, Karl Slifer, E. Schulte, Guy Ron, P. Solvignon, S. May-Tal Beck, J. Song, R. Subedi, E. Piasetzky, R. Michaels, C. F. Perdrisat, B. Craver, Young Do Oh, M. Olson, P. Gueye, C. E. Hyde, G. G. Petratos, V. A. Punjabi, E. McCullough, G. M. Urciuoli, Asghar Askarpour Kabir, Pete Markowitz, A. Kelleher, Ronald Ransome, Ishay Pomerantz, J. J. LeRose, M. Potokar, A. J. Sarty, A. J. R. Puckett, R. Pomatsalyuk, J. Dumas, Xin Qian, C. Dutta, H. F. Ibrahim, A. P. Freyberger, R. Lindgren, M. Meziane, Kent Paschke, A. Shahinyan, B. Sawatzky, E. Kuchina, R. Sparks, Xiaofeng Zhu, S. Strauch, D. G. Meekins, B. L. Berman, F. Cusanno, Z. E. Meziani, A. T. Katramatou, J. Glister, T. Holmstrom, X. Yan, R. J. Feuerbach, J. Arrington, E. Chudakov, Y. Qiang, Fatiha Benmokhtar, B. E. Norum, H. Arenaövel, M. Paolone, J. O. Hansen, J. Roche, W. U. Boeglin, Bryan J. Moffit, A. Camsonne, Franco Garibaldi, H. Yao, M. Schwamb, Byounghoon Lee, Simon Širca, X. Zhan, S. Choi, X. Jiang, R. Shneor, Whitney Armstrong, Kalyan Allada, E. J. Brash, G. J. Kumbartzki, P. Giuliani, Y. Ilieva, M. H. Shabestari, A. Beck, M. Reyhan, Salvatore Frullani, Ronald Gilman, J. P. Chen, Douglas Higinbotham, M. K. Jones, J. R. Calarco, Yannick Rousseau, K. Wang, A. Adeyemi, Bogdan Wojtsekhowski, E. Khrosinkova, Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS), Jefferson Lab Hall A, and Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Subjects: Diffraction, Elastic scattering, Physics, Nuclear and High Energy Physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, Scattering, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nuclear matter, 01 natural sciences, 7. Clean energy, Effective nuclear charge, Cross section (physics), 0103 physical sciences, Nuclear fusion, Atomic physics, Born approximation, 010306 general physics
Abstract: Measurements of elastic electron scattering data within the past decade have highlighted two-photon exchange contributions as a necessary ingredient in theoretical calculations to precisely evaluate hydrogen elastic scattering cross sections. This correction can modify the cross section at the few percent level. In contrast, dispersive effects can cause significantly larger changes from the Born approximation. The purpose of this experiment is to extract the carbon-12 elastic cross section around the first diffraction minimum, where the Born term contributions to the cross section are small to maximize the sensitivity to dispersive effects. The analysis uses the LEDEX data from the high resolution Jefferson Lab Hall A spectrometers to extract the cross sections near the first diffraction minimum of $$^{12}$$ C at beam energies of 362 MeV and 685 MeV. The results are in very good agreement with previous world data, although with less precision. The average deviation from a static nuclear charge distribution expected from linear and quadratic fits indicate a 30.6% contribution of dispersive effects to the cross section at 1 GeV. The magnitude of the dispersive effects near the first diffraction minimum of $$^{12}$$ C has been confirmed to be large with a strong energy dependence and could account for a large fraction of the magnitude for the observed quenching of the longitudinal nuclear response. These effects could also be important for nuclei radii extracted from parity-violating asymmetries measured near a diffraction minimum.
Published: 2020
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3. Novel observation of isospin structure of short-range correlations in calcium isotopes

Author: V. Bellini, A. Daniel, R. Shneor, Juliette Mammei, Simon Širca, Chunhui Chen, Shalev Gilad, F. Garibaldi, J. Leckey, K. A. Aniol, C. Hanretty, Nadia Fomin, S. K. Phillips, M. Hashemi Shabestari, Guy Ron, Z. E. Meziani, T. Averett, A. Shahinyan, S. Iqbal, Kalyan Allada, N. Muangma, R. Subedi, A. Saha, Wouter Deconinck, Ishay Pomerantz, M. Mihovilovic, I. Korover, X. Zhan, D. Anez, P. Aguilera, D. J. Margaziotis, J.-O. Hansen, Ping Zhu, Yujie Qiang, S. A. Wood, E. Cisbani, R. A. Lindgren, J. J. LeRose, P. E. Reimer, Z. Ye, B. E. Norum, V. A. Punjabi, M. Friend, Fatiha Benmokhtar, Karl Slifer, E. Fuchey, John Arrington, V. Sulkosky, Donal Day, Nikolaos Sparveris, Y. Zhang, D. Wang, S. Beck, E. Long, M. Posik, Jie Zhang, X. Bai, Xin Qian, D. Flay, A. Kelleher, M. M. Dalton, S. Riordan, J. W. Watson, D. G. Meekins, N. Kalantarians, Bogdan Wojtsekhowski, Paul Gueye, Nuruzzaman, S. Frullani, D. Nguyen, G. Jin, R. Zielinski, X. Zheng, Brian P. Anderson, R. Michaels, Shanfeng Li, Alexandre Camsonne, A. Beck, B. Zhao, C. Munoz Camacho, H. Kang, D. Gaskell, Douglas Higinbotham, M. Defurne, J. R. M. Annand, K. Pan, Abdurahim Rakhman, E. Piasetzky, M. Huang, P. Solvignon, C. Gu, I. Yaron, H. Al-Bataineh, S. Glamazdin, Larry Weinstein, Ronald Gilman, L. Selvy, Pete Markowitz, J. P. Chen, H. Baghdasaryan, K. Chirapatpimol, Z. Ahmed, X. Qiu, O. Rondon-Aramayo, 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), Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Jefferson Lab Hall A, and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)
Subjects: Triple coincidence, Physics, 010308 nuclear & particles physics, Nuclear Theory, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 3. Good health, Isotopes of calcium, Isospin, 0103 physical sciences, Nuclear Experiment (nucl-ex), Nucleon-Nucleon Interaction, 010306 general physics, Nucleon, Nuclear Experiment, Few-Body Systems, Range (computer programming), Mathematical physics
Abstract: Short Range Correlations (SRCs) have been identified as being responsible for the high momentum tail of the nucleon momentum distribution, n(k). Hard, short-range interactions of nucleon pairs generate the high momentum tail and imprint a universal character on n(k) for all nuclei at large momentum. Triple coincidence experiments have shown a strong dominance of np pairs, but these measurements involve large final state interactions. This paper presents the results from Jefferson Lab experiment E08014 which measured inclusive electron scattering cross-section from Ca isotopes. By comparing the inclusive cross section from 48Ca to 40Ca in a kinematic region dominated by SRCs we provide a new way to study the isospin structure of SRCs., Comment: 7 pages, 3 figures
Published: 2020
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4. Electroexcitation of the Δ+(1232) at low momentum transfer

Author: V. Bellini, C.M. Camacho, E. Schulte, H. Albataineh, J. W. Watson, M. Huang, M. Hashemi Shabestari, J. Sjoegren, C. Gu, Simon Širca, F. Garibaldi, I. Yaron, L. Selvy, M. Khandaker, V. A. Punjabi, T. Holmstrom, E. Fuchey, B. D. Anderson, M. Defurne, W. Tireman, D. J. Margaziotis, R. A. Lindgren, Or Hen, J. P. Chen, I. Korover, E. Piasetzky, Z. E. Meziani, A. Blomberg, H. Baghdasaryan, Olfred Hansen, K. Chirapatpimol, J. R. M. Annand, Juliette Mammei, A. Polychronopoulou, Salvatore Frullani, M. Posik, N. Muangma, X. Zhan, S. K. Phillips, John Arrington, X. Bai, J. Leckey, D. Flay, Nikos Sparveris, Ping Zhu, B. Zhao, Guy Ron, David Hamilton, W. B. Yan, A. Kelleher, X. Zheng, N. Kalantarians, R. Shneor, S. Riordan, Abdurahim Rakhman, A. Saha, Kalyan Allada, Vincent Sulkosky, Z. W. Zhao, Z. Ye, E. Long, Xin Qian, R. Subedi, D. G. Meekins, Bogdan Wojtsekhowski, B. E. Norum, J. LeRose, R. De Leo, M. Mihovilovič, A. Martí Jiménez-Argüello, E. Cisbani, S. Iqbal, M. M. Dalton, W. U. Boeglin, Chunhui Chen, H. Kang, A. Camsonne, Nuruzzaman, Michael Paolone, C. Hanretty, D. Anez, N. Fomin, Shalev Gilad, K. A. Aniol, T. Averett, Wouter Deconinck, Ishay Pomerantz, Z. Ahmed, A. J. Sarty, Fatiha Benmokhtar, D. Wang, S. Beck, Ronald Gilman, Douglas Higinbotham, K. Pan, Yiyang Zhang, A. Beck, Jie Zhang, M. Friend, P. E. Reimer, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Ecole Centrale Paris, Laboratoire de Physique Corpusculaire - Clermont-Ferrand (LPC), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Angular momentum, Nuclear and High Energy Physics, High Energy Physics::Lattice, Nuclear Theory, Constituent quark, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], Nucleon deformation, 01 natural sciences, 7. Clean energy, Atomic, Nuclear physics, Pion, Particle and Plasma Physics, 0103 physical sciences, Coulomb, Effective field theory, Nuclear, CMR, 010306 general physics, Nuclear Experiment, Mathematical Physics, Physics, 010308 nuclear & particles physics, Momentum transfer, Pion electroproduction, Molecular, Nuclear & Particles Physics, lcsh:QC1-999, Quantum electrodynamics, Quadrupole, Nucleon, Astronomical and Space Sciences, lcsh:Physics
Abstract: International audience; We report on new p(e,e′p)π∘p(e,e′p)π∘ measurements at the Δ+(1232)Δ+(1232) resonance at the low momentum transfer region, where the mesonic cloud dynamics is predicted to be dominant and rapidly changing, offering a test bed for chiral effective field theory calculations. The new data explore the Q2Q2 dependence of the resonant quadrupole amplitudes and for the first time indicate that the Electric and the Coulomb quadrupole amplitudes converge as Q2→0Q2→0. The measurements of the Coulomb quadrupole amplitude have been extended to the lowest momentum transfer ever reached, and suggest that more than half of its magnitude is attributed to the mesonic cloud in this region. The new data disagree with predictions of constituent quark models and are in reasonable agreement with dynamical calculations that include pion cloud effects, chiral effective field theory and lattice calculations. The measurements indicate that improvement is required to the theoretical calculations and provide valuable input that will allow their refinements.
Published: 2016
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5. Final Report - Few-Body Studies Using Electromagnetic Interactions

Author: B. E. Norum
Published: 2018
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6. Search for three-nucleon short-range correlations in light nuclei

Author: L. Selvy, P. E. Reimer, M. Hashemi Shabestari, Wouter Deconinck, T. Averett, Karl Slifer, M. M. Dalton, H. Baghdasaryan, S. Riordan, Z. Ahmed, X. Qiu, S. Glamazdin, O. Rondon-Aramayo, X. Zhan, S. A. Wood, M. Posik, X. Bai, Yujie Qiang, N. Kalantarians, Zein-Eddine Meziani, E. Piasetzky, Larry Weinstein, P. Solvignon, Nuruzzaman, Z. Ye, B. E. Norum, Kalyan Allada, Nikolaos Sparveris, Ishay Pomerantz, N. Fomin, J. R. M. Annand, A. Kelleher, Shalev Gilad, J. Arrington, Abdurahim Rakhman, D. Wang, S. Beck, Ronald Gilman, K. A. Aniol, J. O. Hansen, B. Zhao, J. W. Watson, Juliette Mammei, Arijit Saha, M. Huang, E. Fuchey, Paul Gueye, Chunhui Chen, C. Gu, Douglas Higinbotham, I. Korover, Bogdan Wojtsekhowski, R. Michaels, H. Kang, Fatiha Benmokhtar, R. Shneor, A. Shahinyan, C. Munoz Camacho, M. Defurne, A. Camsonne, K. Chirapatpimol, I. Yaron, G. Jin, S. Iqbal, X. Zheng, Xin Qian, R. Subedi, D. J. Margaziotis, K. Pan, Pete Markowitz, D. G. Meekins, H. Albataineh, Vincent Sulkosky, B. D. Anderson, J. LeRose, Yiyang Zhang, A. Beck, P. Aguilera, A. Daniel, R. A. Lindgren, Donal Day, D. Gaskell, Guy Ron, D. Nguyen, D. Flay, C. Hanretty, N. Muangma, S. K. Phillips, M. Friend, M. Mihovilovic, Jie Zhang, E. Cisbani, Jian-Ping Chen, S. Frullani, J. Leckey, R. Zielinski, V. A. Punjabi, D. Anez, E. Long, Ping Zhu, V. Bellini, Simon Širca, F. Garibaldi, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Hall A, Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne [2017-2020] (UCA [2017-2020])-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Light nucleus, Nuclear and High Energy Physics, 010308 nuclear & particles physics, FOS: Physical sciences, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], 01 natural sciences, 3. Good health, Combinatorics, 0103 physical sciences, Nuclear Experiment (nucl-ex), 010306 general physics, Nucleon, Nuclear Experiment, Range (computer programming)
Abstract: We present new data probing short-range correlations (SRCs) in nuclei through the measurement of electron scattering off high-momentum nucleons in nuclei. The inclusive 4He/3He cross section ratio is observed to be both x and Q2 independent for 1.5 < x < 2, confirming the dominance of two- nucleon (2N) short-range correlations (SRCs). For x > 2, our data do not support a previous claim of three-nucleon (3N) correlation dominance. While contributions beyond those from stationary 2N- SRCs are observed, our data show that isolating 3N-SRCs is more complicated than for 2N-SRCs., 6 pages, 2 figures, new experimental results from JLab E08-014
Published: 2018
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7. Final Technical Report - Nuclear Studies with Intermediate Energy Probes

Author: B. E. Norum
Subjects: Materials science, Intermediate energy, Nuclear engineering, Technical report
Published: 2017
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8. Precision measurements of A1n in the deep inelastic regime

Author: S. Choi, Mustafa Canan, Kalyan Allada, H. Yao, M. Friend, A. Deur, Wouter Deconinck, Nuruzzaman, J. P. Chen, B. Sawatzky, F. Garibaldi, M. H. Shabestari, G. D. Cates, S. K. Nanda, Yujie Qiang, R. Subedi, A. Camsonne, N. Muangma, A. Shahinyan, Vincent Sulkosky, O. Glamazdin, Z. Ye, B. E. Norum, V. Mamyan, J. Huang, R. A. Lindgren, J. J. LeRose, Olfred Hansen, Bogdan Wojtsekhowski, X. Deng, X. Zhan, W. Troth, Y. Zhang, D. Flay, A. Lukhanin, B. Moffit, G. Jin, M. Posik, Douglas Higinbotham, C. Dutta, X. Zheng, Zein-Eddine Meziani, Diana Parno, William A. Tobias, D. McNulty, Arijit Saha, P. Solvignon, J. Gomez, Jen-Chieh Peng, S. Golge, Chunhui Chen, S. Širca, Haiyan Gao, Y. X. Ye, Wolfgang Korsch, L. Yuan, X. Jiang, Whitney Armstrong, G. Kumbartzki, B. Zhao, Yiyang Zhang, William Bertozzi, Yingxiao Wang, Amrendra Narayan, Joseph M. Katich, Shalev Gilad, C. W. de Jager, G. B. Franklin, M. M. Dalton, T. Holmstrom, S. Riordan, D. Wang, Ronald Gilman, R. Michaels, Abdurahim Rakhman, L. Guo, E. Long, M. Mihovilovič, A. Kelleher, Vladimir Nelyubin, Young Do Oh, H. F. Ibrahim, E. Chudakov, A. Kolarkar, Nilanga Liyanage, T. Averett, C. E. Hyde, F. Cusanno, Fatiha Benmokhtar, X. Yan, Xin Qian, and L. El Fassi
Subjects: Quantum chromodynamics, Physics, Nuclear physics, Quark, Nuclear and High Energy Physics, Proton, media_common.quotation_subject, Up quark, Neutron, Parton, Deep inelastic scattering, Asymmetry, media_common
Abstract: We have performed precision measurements of the double-spin virtual-photon asymmetry A 1 on the neutron in the deep inelastic scattering regime, using an open-geometry, large-acceptance spectrometer and a longitudinally and transversely polarized 3 He target. Our data cover a wide kinematic range 0.277 ≤ x ≤ 0.548 at an average Q 2 value of 3.078 (GeV/c) 2 , doubling the available high-precision neutron data in this x range. We have combined our results with world data on proton targets to make a leading-order extraction of the ratio of polarized-to-unpolarized parton distribution functions for up quarks and for down quarks in the same kinematic range. Our data are consistent with a previous observation of an A 1 n zero crossing near x = 0.5 . We find no evidence of a transition to a positive slope in ( Δ d + Δ d ¯ ) / ( d + d ¯ ) up to x = 0.548 .
Published: 2015
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9. JLab Measurements of the He3 Form Factors at Large Momentum Transfers

Author: S. Choi, J. Arrington, Kalyan Allada, A. Kelleher, P. Decowski, Ronald Gilman, Pete Markowitz, Riad Suleiman, M. H. Shabestari, H. Yao, B. Craver, L. Y. Zhu, Yingxiao Wang, B. D. Anderson, O. Rondon, R. A. Lindgren, J. J. LeRose, Bogdan Wojtsekhowski, J. P. Chen, G. J. Kumbartzki, G. Lott, B. Hahn, V. Sulkosky, J. Huang, G. M. Urciuoli, Douglas Higinbotham, Alexandre Camsonne, D. J. Margaziotis, A. Acha, X. Zheng, Bryan J. Moffit, J.-O. Hansen, B. E. Norum, R. Subedi, E. Chudakov, J. A. Gomez, S. Marrone, F. Garibaldi, C. Dutta, X. Yan, Z. E. Meziani, L. E. Marcucci, Houbing Lu, Mauro Iodice, Xin Qian, W. M. Zhang, A. Kievsky, G. G. Petratos, A. R. Baldwin, Michele Viviani, E. Folts, A. Shahinyan, S. Frullani, P. Solvignon, E. Khrosinkova, A. T. Katramatou, A. Saha, J. Segal, E. Cisbani, A. J. R. Puckett, M. Olson, D. G. Meekins, T. Holmstrom, Bumsung Lee, R. Michaels, B. Sawatzky, E. Kuchina, Nikos Sparveris, and X. Jiang
Subjects: Diffraction, Physics, 010308 nuclear & particles physics, Scattering, Form factor (quantum field theory), General Physics and Astronomy, Charge (physics), Electron, 01 natural sciences, Momentum, Nuclear physics, Recoil, 0103 physical sciences, Magnetic form factor, Nuclear Experiment, 010306 general physics
Abstract: The charge and magnetic form factors, FC and FM, of 3He have been extracted in the kinematic range 25 fm-2 < Q2 < 61 fm-2 from elastic electron scattering by detecting 3He recoil nuclei and electrons in coincidence with the High Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The measurements are indicative of a second diffraction minimum for the magnetic form factor, which was predicted in the Q2 range of this experiment, and of a continuing diffractive structure for the charge form factor. The data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the three-body nuclear problem.
Published: 2017
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10. First measurement of unpolarized semi-inclusive deep-inelastic scattering cross sections from a He3 target

Author: Nilanga Liyanage, D. J. Margaziotis, T. Liu, G. D. Cates, X. Zhan, Young Do Oh, Y. Li, E. Cisbani, P. C. Bradshaw, D. McNulty, Arijit Saha, C. Dutta, J. C. Cornejo, A. Kolarkar, Simon Širca, Chunhui Chen, R. A. Lindgren, J. J. LeRose, F. Garibaldi, A. Shahinyan, P. A. M. Dolph, F. Cusanno, William A. Tobias, L. G. Tang, Abdurahim Rakhman, X. Yan, Y. Zhang, W. Kim, V. Sulkosky, A. Deur, M. Huang, Ronald Ransome, H. Ding, H. F. Ibrahim, H. Yao, R. Michaels, Mustafa Canan, Xin Qian, S. K. Phillips, Kalyan Allada, William Bertozzi, Yanxi Zhang, Bogdan Wojtsekhowski, T. Averett, X. Jiang, C. Munoz Camacho, B. Zhao, L. Guo, E. Long, M. M. Dalton, Wouter Deconinck, M. Posik, L. El Fassi, S. Riordan, Wolfgang Korsch, P. E. Bosted, Haiyan Gao, Zein-Eddine Meziani, Ronald Gilman, David Hamilton, M. H. Shabestari, Pete Markowitz, Y. F. Wang, E. Chudakov, S. Frullani, X. Zong, A. Kelleher, M. Osipenko, I. Vilardi, Xiaofeng Zhu, Dipanwita Dutta, X. Deng, B. Sawatzky, Jen-Chieh Peng, G. Jin, A. J. R. Puckett, B. Moffit, Y. X. Ye, Houbing Lu, X. Zheng, S. Stepanyan, W. Chen, Fatiha Benmokhtar, R. De Leo, T. Holmstrom, L. Yuan, Vladimir Nelyubin, R. Subedi, Shalev Gilad, Diana Parno, K. Chirapatpimol, J. P. Chen, C. W. de Jager, O. Glamazdin, E. Schulte, K. A. Aniol, Olfred Hansen, J. R. M. Annand, S. K. Nanda, Yujie Qiang, S. Golge, L. Y. Zhu, J. Huang, G. M. Urciuoli, Alexandre Camsonne, Z. Ye, B. E. Norum, Y. Zhao, X. Li, Mauro Iodice, Douglas Higinbotham, M. K. Jones, K. Wang, S. Marrone, Amrendra Narayan, Joseph M. Katich, and D. Gaskell
Subjects: Quark, Quantum chromodynamics, Physics, Particle physics, 010308 nuclear & particles physics, Scattering, Quark model, Deep inelastic scattering, 01 natural sciences, Nuclear physics, 0103 physical sciences, Neutron, Nuclear cross section, 010306 general physics, Nucleon
Abstract: The unpolarized semi-inclusive deep-inelastic scattering (SIDIS) differential cross sections in He3(e,e′π±)X have been measured for the first time in Jefferson Lab experiment E06-010 with a 5.9GeVe− beam on a He3 gas target. The experiment focuses on the valence quark region, covering a kinematic range 0.12
Published: 2017
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11. Measurements ofd2nandA1n: Probing the neutron spin structure

Author: T. Averett, C. E. Hyde, A. Saha, R. Subedi, Nilanga Liyanage, R. A. Lindgren, J. J. LeRose, V. Sulkosky, S. K. Nanda, Yujie Qiang, D. Flay, S. Riordan, Fatiha Benmokhtar, Simon Širca, M. H. Shabestari, F. Garibaldi, Bogdan Wojtsekhowski, H. Yao, Wolfgang Korsch, Young Do Oh, V. Mamyan, G. D. Cates, A. Kolarkar, R. Michaels, M. M. Dalton, Douglas Higinbotham, Whitney Armstrong, X. Deng, C. Dutta, H. F. Ibrahim, N. Muangma, William A. Tobias, M. Friend, W. Troth, E. Chudakov, Diana Parno, M. Mihovilovic, D. McNulty, Haiyan Gao, X. Zhan, G. J. Kumbartzki, G. Jin, J. P. Chen, J. Gomez, B. Sawatzky, M. Posik, X. Zheng, X. Jiang, Chunhui Chen, X. Yan, Ronald Ransome, Wouter Deconinck, G. B. Franklin, B. Zhao, L. Guo, Z. Ye, B. E. Norum, T. Holmstrom, Xin Qian, A. Shahinyan, E. Long, Y. Zhang, S. Choi, Jen-Chieh Peng, A. Kelleher, J. Huang, A. Lukhanin, Yingxiao Wang, L. El Fassi, Mustafa Canan, Kalyan Allada, Vladimir Nelyubin, Shalev Gilad, L. Yuan, C. W. de Jager, Bryan J. Moffit, S. Golge, Abdurahim Rakhman, Z. E. Meziani, F. Cusanno, P. Solvignon, A. Deur, Yiyang Zhang, Y. X. Ye, William Bertozzi, Amrendra Narayan, Joseph M. Katich, D. Wang, Ronald Gilman, O. Glamazdin, Olfred Hansen, Alexandre Camsonne, and Nuruzzaman
Subjects: Quark, Physics, Quantum chromodynamics, QCD sum rules, Particle physics, 010308 nuclear & particles physics, Constituent quark, Lattice QCD, Deep inelastic scattering, 01 natural sciences, 0103 physical sciences, High Energy Physics::Experiment, Neutron, Atomic physics, 010306 general physics, Electron scattering
Abstract: We report on the results of the E06-014 experiment performed at Jefferson Lab in Hall A, where a precision measurement of the twist-3 matrix element d_2 of the neutron (d^n_2) was conducted. The quantity dn_2 represents the average color Lorentz force a struck quark experiences in a deep inelastic electron scattering event off a neutron due to its interaction with the hadronizing remnants. This color force was determined from a linear combination of the third moments of the ^3He spin structure functions, g_1 and g_2, after nuclear corrections had been applied to these moments. The structure functions were obtained from a measurement of the unpolarized cross section and of double-spin asymmetries in the scattering of a longitudinally polarized electron beam from a transversely and a longitudinally polarized ^3He target. The measurement kinematics included two average Q^2 bins of 3.2 GeV^2 and 4.3 GeV^2, and Bjorken-x 0.25≤ x ≤0.90 covering the deep inelastic and resonance regions. We have found that d^n_2 is small and negative for ⟨Q^2⟩=3.2 GeV^2, and even smaller for ⟨Q^2⟩=4.3 GeV^2, consistent with the results of a lattice QCD calculation. The twist-4 matrix element f^n_2 was extracted by combining our measured d^n_2 with the world data on the first moment in x of g^n_1, Γ^n_1. We found f^n_2 to be roughly an order of magnitude larger than dn2. Utilizing the extracted d^n_2 and f^n_2 data, we separated the Lorentz color force into its electric and magnetic components, F^(y,n)_E and F^(y,n)_B, and found them to be equal and opposite in magnitude, in agreement with the predictions from an instanton model but not with those from QCD sum rules. Furthermore, using the measured double-spin asymmetries, we have extracted the virtual photon-nucleon asymmetry on the neutron A^n_1, the structure function ratio g^n_1/F^n_1, and the quark ratios (Δu+Δu)/(u+u) and (Δd+Δd)/(d+d). These results were found to be consistent with deep-inelastic scattering world data and with the prediction of the constituent quark model but at odds with the perturbative quantum chromodynamics predictions at large x.
Published: 2016
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12. Proton radius from electron scattering data

Author: D. G. Meekins, B. E. Norum, Al Amin Kabir, Vincent Lin, Douglas Higinbotham, and Brad Sawatzky
Subjects: Physics, Nuclear Theory, Proton, 010308 nuclear & particles physics, Scattering, Extrapolation, FOS: Physical sciences, Mathematical Physics (math-ph), Radius, 01 natural sciences, Lamb shift, Nuclear Theory (nucl-th), Nuclear physics, Dipole, Charge radius, 0103 physical sciences, Physics::Atomic Physics, Nuclear Experiment (nucl-ex), Nuclear Experiment, 010306 general physics, Electron scattering, Mathematical Physics
Abstract: [Background] The proton charge radius extracted from recent muonic hydrogen Lamb shift measurements is significantly smaller than that extracted from atomic hydrogen and electron scattering measurements. [Purpose] In an attempt to understand the discrepancy, we review high-precision electron scattering results from Mainz, Jefferson Lab, Saskatoon and Stanford. [Method] We make use of stepwise regression techniques using the $F$-test as well as the Akaike information criterion to systematically determine the predictive variables to use for a given set and range of electron scattering data as well as to provide multivariate error estimates. [Results] Starting with the precision, low four-momentum transfer ($Q^2$) data from Mainz (1980) and Saskatoon (1974), we find that a stepwise regression of the Maclaurin series using the $F$-test as well as the Akaike information criterion justify using a linear extrapolation which yields a value for the proton radius that is consistent with the result obtained from muonic hydrogen measurements. Applying the same Maclaurin series and statistical criteria to the 2014 Rosenbluth results on $G_E$ from Mainz, we again find that the stepwise regression tends to favor a radius consistent with the muonic hydrogen radius but produces results that are extremely sensitive to the range of data included in the fit. Making use of the high-$Q^2$ data on $G_E$ to select functions which extrapolate to high $Q^2$, we find that a Pad\'e ($N=M=1$) statistical model works remarkably well, as does a dipole function with a 0.84 fm radius, $G_E(Q^2) = ( 1 + Q^2/0.66\,\mathrm{GeV}^2)^{-2}$. [Conclusions] From this statistical analysis, we conclude that the electron scattering result and the muonic hydrogen result are consistent. It is the atomic hydrogen results that are the outliers., Comment: 10 pages, 7 figures, 7 tables
Published: 2016
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13. High-precision measurement of the proton elastic form factor ratio μpGE/GM at low Q2

Author: F. Itard, P. E. Reimer, T. Holmstrom, William Bertozzi, John Arrington, S. Choi, A. Saha, Kalyan Allada, C. Dutta, Bogdan Wojtsekhowski, S. Strauch, Ronald Ransome, Xin Qian, Ishay Pomerantz, D. G. Meekins, X. Zhan, S. Riordan, R. Shneor, M. H. Shabestari, I. Vilardi, P. Solvignon, R. De Leo, W. U. Boeglin, R. Subedi, D. J. Margaziotis, R. Michaels, R. J. Holt, E. Piasetzky, J. P. Chen, M. Olson, B. Hahn, J. Glister, A. J. Sarty, E. Schulte, Simon Širca, J. Huang, Yujie Qiang, G. M. Huber, F. Garibaldi, K. Chirapatpimol, K. Hafidi, E. Chudakov, Yingxiao Wang, M. Johnson, S. May-Tal Beck, E. Cisbani, J. O. Hansen, Abdurahim Rakhman, Nikolaos Sparveris, Shalev Gilad, E. Fuchey, C. W. de Jager, Z. Ye, B. E. Norum, Y. Zhang, X. Jiang, E. Long, D. S. Armstrong, J. Reinhold, S. Frullani, D. Protopopescu, B. Moffit, A. Shahinyan, Douglas Higinbotham, R. A. Lindgren, J. J. LeRose, Guy Ron, Joseph M. Katich, B. Sawatzky, Vincent Sulkosky, P. Decowski, and Ronald Gilman
Subjects: Physics, Nuclear and High Energy Physics, Recoil, Proton, Hydrogen, chemistry, Charge radius, chemistry.chemical_element, Electron, Atomic physics, Polarization (waves), Exotic atom, Lamb shift
Abstract: We report a new, high-precision measurement of the proton elastic form factor ratio μ p G E / G M for the four-momentum transfer squared Q 2 = 0.3 – 0.7 ( GeV / c ) 2 . The measurement was performed at Jefferson Lab (JLab) in Hall A using recoil polarimetry. With a total uncertainty of approximately 1%, the new data clearly show that the deviation of the ratio μ p G E / G M from unity observed in previous polarization measurements at high Q 2 continues down to the lowest Q 2 value of this measurement. The updated global fit that includes the new results yields an electric (magnetic) form factor roughly 2% smaller (1% larger) than the previous global fit in this Q 2 range. We obtain new extractions of the proton electric and magnetic radii, which are 〈 r E 2 〉 1 / 2 = 0.875 ± 0.010 fm and 〈 r M 2 〉 1 / 2 = 0.867 ± 0.020 fm . The charge radius is consistent with other recent extractions based on the electron–proton interaction, including the atomic hydrogen Lamb shift measurements, which suggests a missing correction in the comparison of measurements of the proton charge radius using electron probes and the recent extraction from the muonic hydrogen Lamb shift.
Published: 2011
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14. Polarization observables in deuteron photodisintegration below 360 MeV

Author: L. Coman, Karl Slifer, M. H. Shabestari, E. Kuchina, J. Dumas, J. Song, R. Michaels, Bogdan Wojtsekhowski, M. Olson, Young Do Oh, Hartmuth Arenhövel, Douglas Higinbotham, T. Holmstrom, M. K. Jones, R. Shneor, B. L. Berman, J. Glister, Arijit Saha, Yannick Rousseau, S. Choi, H. F. Ibrahim, Franco Garibaldi, W. Armstrong, K. Wang, Kalyan Allada, John Arrington, R. Sparks, E. J. Brash, M. Paolone, C. E. Hyde, Guy Ron, Salvatore Frullani, B. E. Norum, E. Chudakov, Hyekoo Kang, J. R. Calarco, H. Yao, P. Solvignon, J. O. Hansen, S. Širca, Ronald Ransome, E. Schulte, Ishay Pomerantz, Yujie Qiang, R. J. Feuerbach, B. Sawatzky, A. Beck, Andrew Puckett, J. Roche, J. P. Chen, Xin Qian, X. Zhu, G. Kumbartzki, R. Subedi, A. P. Freyberger, Byounghoon Lee, B. Craver, D. G. Meekins, C. F. Perdrisat, Kent Paschke, C. W. de Jager, R. Pomatsalyuk, Emily M. McCullough, F. Cusanno, M. Reyhan, Bryan J. Moffit, A. Shahinyan, C. Dutta, M. Potokar, Ronald Gilman, W. U. Boeglin, A. Camsonne, S. Strauch, E. Khrosinkova, M. Meziane, Pete Markowitz, G. M. Urciuoli, F. Benmokhtar, R. A. Lindgren, J. J. LeRose, A. Kelleher, Z. E. Meziani, X. Yan, E. Piasetzky, X. Jiang, S. May-Tal Beck, V. A. Punjabi, M. Schwamb, X. Zhan, Y. Ilieva, and A. J. Sarty
Subjects: Physics, Nuclear and High Energy Physics, Photon, Meson, 010308 nuclear & particles physics, Nuclear Theory, Polarization observables, FOS: Physical sciences, Polarization (waves), 01 natural sciences, Recoil proton, Nuclear physics, Baryon, Deuterium, Photodisintegration, 0103 physical sciences, Nuclear Experiment (nucl-ex), Atomic physics, Nuclear Experiment, 010306 general physics
Abstract: High precision measurements of induced and transferred recoil proton polarization in d(polarized gamma, polarized p})n have been performed for photon energies of 277--357 MeV and theta_cm = 20 degrees -- 120 degrees. The measurements were motivated by a longstanding discrepancy between meson-baryon model calculations and data at higher energies. At the low energies of this experiment, theory continues to fail to reproduce the data, indicating that either something is missing in the calculations and/or there is a problem with the accuracy of the nucleon-nucleon potential being used., Comment: 5 pages, 2 figures
Published: 2011
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15. Measurement of the Target-Normal Single-Spin Asymmetry in Quasielastic Scattering from the ReactionHe3↑(e,e′ )

Author: H. F. Ibrahim, E. Piasetzky, G. D. Cates, Y. Zhang, J. Gomez, Bogdan Wojtsekhowski, S. Frullani, C. Dutta, Chunhui Chen, S. Širca, E. Chudakov, William A. Tobias, R. Subedi, Mustafa Canan, Kalyan Allada, G. Jin, X. Zhan, B. Zhao, S. Golge, R. Michaels, X. Zheng, B. Schoenrock, P. Monaghan, B. D. Anderson, O. Glamazdin, Olfred Hansen, J. R. M. Annand, A. Saha, F. Garibaldi, S. K. Nanda, H. P. Khanal, Yujie Qiang, Andrew Puckett, M. H. Shabestari, Pete Markowitz, H. Kang, C. Ayerbe-Gayoso, Z. Ye, M. Posik, B. E. Norum, W. Luo, Rocco Schiavilla, Diana Parno, X. Deng, P. C. Bradshaw, X. Jiang, B. Sawatzky, Yingxiao Wang, Xin Qian, R. De Leo, G. M. Urciuoli, N. Muangma, T. Holmstrom, L. Y. Zhu, Shalev Gilad, Yiyang Zhang, C. W. de Jager, Haiyan Gao, J. P. Chen, L. El Fassi, W. U. Boeglin, Joseph M. Katich, J. Huang, S. Riordan, E. Long, Douglas Higinbotham, M. K. Jones, X. Qiu, M. Mihovilovič, E. Jensen, J. St. John, B. Moffit, Wolfgang Korsch, W. Tireman, K. Pan, K. Wang, A. Deur, P. M. King, Guy Ron, D. Wang, Ronald Gilman, J. W. Watson, V. A. Punjabi, A. Shahinyan, M. Meziane, A. Camsonne, H.-J. Lu, Vincent Sulkosky, T. Averett, R. A. Lindgren, J. J. LeRose, and D. Flay
Subjects: Physics, Quasielastic scattering, Particle physics, Scattering, media_common.quotation_subject, General Physics and Astronomy, Parton, Polarization (waves), Asymmetry, Nuclear physics, High Energy Physics::Experiment, Neutron, Nuclear Experiment, Nucleon, Lepton, media_common
Abstract: We report the first measurement of the target single-spin asymmetry, A(y), in quasielastic scattering from the inclusive reaction (3)He(↑)(e,e') on a (3)He gas target polarized normal to the lepton scattering plane. Assuming time-reversal invariance, this asymmetry is strictly zero for one-photon exchange. A nonzero A(y) can arise from the interference between the one- and two-photon exchange processes which is sensitive to the details of the substructure of the nucleon. An experiment recently completed at Jefferson Lab yielded asymmetries with high statistical precision at Q(2)=0.13, 0.46, and 0.97 GeV(2). These measurements demonstrate, for the first time, that the (3)He asymmetry is clearly nonzero and negative at the 4σ-9σ level. Using measured proton-to-(3)He cross-section ratios and the effective polarization approximation, neutron asymmetries of -(1-3)% were obtained. The neutron asymmetry at high Q(2) is related to moments of the generalized parton distributions (GPDs). Our measured neutron asymmetry at Q(2)=0.97 GeV(2) agrees well with a prediction based on two-photon exchange using a GPD model and thus provides a new, independent constraint on these distributions.
Published: 2015
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16. Photodisintegration ofLi7with progeny nuclei in excited states

Author: B. E. Norum, Ward Wurtz, S. Stave, S. Kucuker, B. Sawatzky, R. E. Pywell, Musa Ahmed, and H. R. Weller
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, 010308 nuclear & particles physics, Photodisintegration, Excited state, 0103 physical sciences, 010306 general physics, 01 natural sciences
Published: 2015
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17. Double spin asymmetries of inclusive hadron electroproduction from a transversely polarizedHe3target

Author: S. K. Nanda, Yujie Qiang, H. Yao, M. M. Dalton, S. Riordan, Bogdan Wojtsekhowski, S. S. Stepanyan, Mustafa Canan, T. Holmstrom, Wolfgang Korsch, Kalyan Allada, J. C. Cornejo, L. G. Tang, Y. Zhang, D. McNulty, P. A. M. Dolph, T. Averett, Abdurahim Rakhman, M. Huang, Jen-Chieh Peng, X. Zong, S. K. Phillips, B. Sawatzky, X. Li, G. Jin, X. Zheng, C. Dutta, Nilanga Liyanage, Franco Garibaldi, L. Yuan, A. Camsonne, Chunhui Chen, B. Zhao, L. Guo, K. Chirapatpimol, Salvatore Frullani, Y. Li, D. J. Margaziotis, Simon Širca, Young Do Oh, Vincent Sulkosky, E. Long, Mauro Iodice, F. Cusanno, L. Y. Zhu, William A. Tobias, W. Kim, A. Deur, E. Cisbani, A. J. R. Puckett, J. P. Chen, Fatiha Benmokhtar, S. Golge, A. Kelleher, H. J. Lu, A. Shahinyan, R. A. Lindgren, J. J. LeRose, Yong Zhang, I. Vilardi, H. Ding, A. Kolarkar, Vladimir Nelyubin, J. Huang, G. M. Urciuoli, H. F. Ibrahim, E. Schulte, Xiaofeng Zhu, Dipangkar Dutta, R. Michaels, G. D. Cates, X. Zhan, E. Chudakov, M. Osipenko, William Bertozzi, Haiyan Gao, O. Glamazdin, Z. Ye, B. E. Norum, Diana Parno, S. Marrone, Olfred Hansen, J. R. M. Annand, Y. Zhao, David Hamilton, Pete Markowitz, A. Saha, M. H. Shabestari, P. Bosted, Y. X. Ye, R. De Leo, X. Yan, Ronald Ransome, Xin Qian, Yingxiao Wang, P. C. Bradshaw, M. Posik, X. Deng, Zein-Eddine Meziani, L. El Fassi, C. Muñoz Camacho, Shalev Gilad, C. W. de Jager, K. A. Aniol, Wouter Deconinck, R. Subedi, Amrendra Narayan, Joseph M. Katich, D. Gaskell, Ronald Gilman, Douglas Higinbotham, M. K. Jones, B. Moffit, K. Wang, X. Jiang, and W. Chen
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Scattering, Hadron, chemistry.chemical_element, Parton, Horizontal plane, Polarization (waves), Helicity, Nuclear physics, chemistry, Cathode ray, High Energy Physics::Experiment, Nuclear Experiment, Helium
Abstract: We report the measurement of beam-target double-spin asymmetries ALT in the inclusive production of identified hadrons, e +³He↑ → h + X, using a longitudinally polarized 5.9 GeV electron beam and a transversely polarized ³He target. Hadrons (π±, K± and proton) were detected at 16° with an average momentum h>=2.35 GeV/c and a transverse momentum (pT) coverage from 0.60 to 0.68 GeV/c. Asymmetries from the ³He target were observed to be non-zero for π± production when the target was polarized transversely in the horizontal plane. The π⁺ and π⁻ asymmetries have opposite signs, analogous to the behavior of ALT in semi-inclusive deep-inelastic scattering.
Published: 2015
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18. Spectroscopy ofLiΛ9by electroproduction

Author: T. Miyoshi, P. Brindza, V. A. Punjabi, W. U. Boeglin, X. Jiang, Bogdan Wojtsekhowski, L. Lagamba, D. J. Millener, E. Cisbani, L. Coman, V. Sulkosky, Pete Markowitz, H. Ueno, S. Marrone, R. Michaels, V. M. Rodriguez, Jaideep Singh, B. E. Norum, P. E. Reimer, K. Kino, B. Reitz, R. De Leo, Pavlo Baturin, S. K. Nanda, Yujie Qiang, P. Bydžovský, P.Y. Bertin, S. Colilli, C. Munoz Camacho, H. Breuer, Y. Okasyasu, Vladimir Nelyubin, Z. E. Meziani, Salvatore Frullani, M. Lucentini, J. P. Chen, G. de Cataldo, L. J. Kaufman, G. M. Urciuoli, A. Shahinyan, K. A. Aniol, Franco Garibaldi, Joerg Reinhold, C. E. Hyde, F. Cusanno, A. Deur, Simon Širca, B. Kross, Douglas Higinbotham, Kent Paschke, Tohru Suzuki, E. Piasetzky, M. Gricia, Eugenio Nappi, J. Gomez, A. Acha, D. J. Margaziotis, P. E. Ulmer, C. Zorn, Mauro Iodice, C. C. Chang, D. Hayes, H. Benaoum, H. F. Ibrahim, R. A. Lindgren, J. J. LeRose, A. Saha, X. Zheng, R. J. Feuerbach, P. Veneroni, R. Fratoni, P. Ambrozewicz, Seonho Choi, K. I. Blomqvist, E. Chudakov, C. Ferdi, T. Holmstrom, J. O. Hansen, K. McCormick, J. Segal, A. Camsonne, A. J. Sarty, R. Subedi, Maryam Moteabbed, M. Sotona, Olivier Gayou, R. Snyder, C. W. de Jager, Bryan J. Moffit, R. Roche, F. Giuliani, P. Monaghan, B. Craver, C. F. Perdrisat, E. Folts, F. Santavenere, E. Voutier, and P. Solvignon
Subjects: Superconductivity, Physics, Nuclear and High Energy Physics, Nuclear Theory, Order (ring theory), Atomic physics, Nuclear Experiment, Ground state, Hypernucleus, Spectroscopy, Lambda, Energy (signal processing), Spectral line
Abstract: Background: In the absence of accurate data on the free two-body hyperon-nucleon interaction, the spectra of hypernuclei provides information on the details of the effective hyperon-nucleon interaction.Purpose: To obtain a high-resolution binding-energy spectrum for the ${}^{9}\mathrm{Be}(e,{e}^{\ensuremath{'}}{K}^{+})_{\ensuremath{\Lambda}}^{9}\mathrm{Li}$ reaction.Method: Electroproduction of the hypernucleus $_{\ensuremath{\Lambda}}^{9}\mathrm{Li}$ has been studied for the first time with sub-MeV energy resolution in Hall A at Jefferson Lab on a $^{9}\mathrm{Be}$ target. In order to increase the counting rate and to provide unambiguous kaon identification, two superconducting septum magnets and a ring imaging Cherenkov detector were added to the Hall A standard equipment.Results: The cross section to low-lying states of $_{\ensuremath{\Lambda}}^{9}\mathrm{Li}$ is concentrated within 3 MeV of the ground state and can be fit with four peaks. The positions of the doublets agree with theory while a disagreement could exist with respect to the relative strengths of the peaks in the doublets. The $\ensuremath{\Lambda}$ separation energy, ${B}_{\ensuremath{\Lambda}}$, of $8.36\ifmmode\pm\else\textpm\fi{}0.08$ (stat.) $\ifmmode\pm\else\textpm\fi{}0.08$ (syst.) MeV was measured, in agreement with an earlier experiment.
Published: 2015
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19. Precision Measurement of the p(e,e^{'}p)π^{0} Reaction at Threshold

Author: K, Chirapatpimol, M H, Shabestari, R A, Lindgren, L C, Smith, J R M, Annand, D W, Higinbotham, B, Moffit, V, Nelyubin, B E, Norum, K, Allada, K, Aniol, K, Ardashev, D S, Armstrong, R A, Arndt, F, Benmokhtar, A M, Bernstein, W, Bertozzi, W J, Briscoe, L, Bimbot, A, Camsonne, J-P, Chen, S, Choi, E, Chudakov, E, Cisbani, F, Cusanno, M M, Dalton, C, Dutta, K, Egiyan, C, Fernàndez-Ramìrez, R, Feuerbach, K G, Fissum, S, Frullani, F, Garibaldi, O, Gayou, R, Gilman, S, Gilad, J, Goity, J, Gomez, B, Hahn, D, Hamilton, J-O, Hansen, J, Huang, R, Igarashi, D, Ireland, C W, de Jager, X, Jin, X, Jiang, T, Jinasundera, J, Kellie, C E, Keppel, N, Kolb, J, LeRose, N, Liyanage, K, Livingston, D, McNulty, L, Mercado, R, Michaels, M, Mihovilovič, S, Qian, X, Qian, S, Mailyan, V, Mamyan, S, Marrone, P, Monaghan, S, Nanda, C F, Perdrisat, E, Piasetzky, D, Protopopescu, V, Punjabi, Y, Qiang, I A, Rachek, A, Rakhman, S, Riordan, G, Ron, G, Rosner, A, Saha, B, Sawatzky, A, Shahinyan, S, Širca, N, Sparveris, R R, Subedi, R, Suleiman, I, Strakovsky, V, Sulkosky, J, Moinelo, H, Voskanyan, K, Wang, Y, Wang, J, Watson, D, Watts, B, Wojtsekhowski, R L, Workman, H, Yao, X, Zhan, and Y, Zhang
Abstract: New results are reported from a measurement of π^{0} electroproduction near threshold using the p(e,e^{'}p)π^{0} reaction. The experiment was designed to determine precisely the energy dependence of s- and p-wave electromagnetic multipoles as a stringent test of the predictions of chiral perturbation theory (ChPT). The data were taken with an electron beam energy of 1192 MeV using a two-spectrometer setup in Hall A at Jefferson Lab. For the first time, complete coverage of the ϕ_{π}^{*} and θ_{π}^{*} angles in the pπ^{0} center of mass was obtained for invariant energies above threshold from 0.5 up to 15 MeV. The 4-momentum transfer Q^{2} coverage ranges from 0.05 to 0.155 (GeV/c)^{2} in fine steps. A simple phenomenological analysis of our data shows strong disagreement with p-wave predictions from ChPT for Q^{2}0.07 (GeV/c)^{2}, while the s-wave predictions are in reasonable agreement.
Published: 2015

20. Measurement of the Target-Normal Single-Spin Asymmetry in Quasielastic Scattering from the Reaction (3)He(↑)(e,e')

Author: Y-W, Zhang, E, Long, M, Mihovilovič, G, Jin, K, Allada, B, Anderson, J R M, Annand, T, Averett, C, Ayerbe-Gayoso, W, Boeglin, P, Bradshaw, A, Camsonne, M, Canan, G D, Cates, C, Chen, J P, Chen, E, Chudakov, R, De Leo, X, Deng, A, Deur, C, Dutta, L, El Fassi, D, Flay, S, Frullani, F, Garibaldi, H, Gao, S, Gilad, R, Gilman, O, Glamazdin, S, Golge, J, Gomez, O, Hansen, D W, Higinbotham, T, Holmstrom, J, Huang, H, Ibrahim, C W, de Jager, E, Jensen, X, Jiang, J, St John, M, Jones, H, Kang, J, Katich, H P, Khanal, P, King, W, Korsch, J, LeRose, R, Lindgren, H-J, Lu, W, Luo, P, Markowitz, M, Meziane, R, Michaels, B, Moffit, P, Monaghan, N, Muangma, S, Nanda, B E, Norum, K, Pan, D, Parno, E, Piasetzky, M, Posik, V, Punjabi, A J R, Puckett, X, Qian, Y, Qiang, X, Qiu, S, Riordan, G, Ron, A, Saha, B, Sawatzky, R, Schiavilla, B, Schoenrock, M, Shabestari, A, Shahinyan, S, Širca, R, Subedi, V, Sulkosky, W A, Tobias, W, Tireman, G M, Urciuoli, D, Wang, K, Wang, Y, Wang, J, Watson, B, Wojtsekhowski, Z, Ye, X, Zhan, Y, Zhang, X, Zheng, B, Zhao, and L, Zhu
Abstract: We report the first measurement of the target single-spin asymmetry, A(y), in quasielastic scattering from the inclusive reaction (3)He(↑)(e,e') on a (3)He gas target polarized normal to the lepton scattering plane. Assuming time-reversal invariance, this asymmetry is strictly zero for one-photon exchange. A nonzero A(y) can arise from the interference between the one- and two-photon exchange processes which is sensitive to the details of the substructure of the nucleon. An experiment recently completed at Jefferson Lab yielded asymmetries with high statistical precision at Q(2)=0.13, 0.46, and 0.97 GeV(2). These measurements demonstrate, for the first time, that the (3)He asymmetry is clearly nonzero and negative at the 4σ-9σ level. Using measured proton-to-(3)He cross-section ratios and the effective polarization approximation, neutron asymmetries of -(1-3)% were obtained. The neutron asymmetry at high Q(2) is related to moments of the generalized parton distributions (GPDs). Our measured neutron asymmetry at Q(2)=0.97 GeV(2) agrees well with a prediction based on two-photon exchange using a GPD model and thus provides a new, independent constraint on these distributions.
Published: 2015

21. Measurement of Double-Polarization Asymmetries in the QuasielasticHe→3(e→,e′d)Process

Author: P. U. Sauer, M. Viviani, V. A. Punjabi, T. Averett, W. Tireman, P. M. King, Bogdan Wojtsekhowski, Yiyang Zhang, M. H. Shabestari, C. Dutta, William A. Tobias, F. Garibaldi, H. P. Khanal, Joseph M. Katich, A. Shahinyan, Simon Širca, R. Skibiński, Mustafa Canan, H. Kang, Kalyan Allada, B. D. Anderson, M. Mihovilovic, Z. Ye, Douglas Higinbotham, A. Deltuva, A. Deur, M. K. Jones, B. E. Norum, G. D. Cates, X. Deng, E. Jensen, Y. Zhang, Yingxiao Wang, Wolfgang Korsch, K. Pan, X. Jiang, Henryk Witała, L. E. Marcucci, K. Wang, L. Y. Zhu, G. M. Urciuoli, Xin Qian, N. Muangma, Shalev Gilad, C. W. de Jager, J. St. John, S. Riordan, X. Zhan, B. Moffit, A. Kievsky, B. Schoenrock, S. Golge, H. F. Ibrahim, L. El Fassi, W. U. Boeglin, Diana Parno, E. Long, J. Watson, D. Wang, E. Chudakov, Pete Markowitz, Ronald Gilman, R. A. Lindgren, J. J. LeRose, O. Glamazdin, R. De Leo, Olfred Hansen, J. R. M. Annand, G. Jin, J. P. Chen, W. Luo, X. Zheng, Haiyan Gao, B. Zhao, S. K. Nanda, J. Huang, Yujie Qiang, Andrew Puckett, J. Gomez, P. Monaghan, Rocco Schiavilla, D. Flay, B. Sawatzky, M. Meziane, A. Camsonne, T. Holmstrom, H.-J. Lu, Vincent Sulkosky, Jacek Golak, X. Qui, R. Michaels, M. Posik, E. Piasetzky, S. Frullani, R. Subedi, Arijit Saha, Chunhui Chen, and P. C. Bradshaw
Subjects: Nuclear physics, Physics, Scattering, Hadron, General Physics and Astronomy, Electron, Kinematics, Few-body systems, Functional dependency, Polarization (waves), Omega
Abstract: We present a precise measurement of double-polarization asymmetries in the 3He(e,e'd) reaction. This particular process is a uniquely sensitive probe of hadron dynamics in 3He and the structure of the underlying electromagnetic currents. The measurements have been performed in and around quasi-elastic kinematics at Q2=0.25(GeV/c)2 for missing momenta up to 270MeV/c. The asymmetries are in fair agreement with the state-of-the-art calculations in terms of their functional dependencies on pm and omega, but are systematically offset. Beyond the region of the quasi-elastic peak, the discrepancies become even more pronounced. Thus, our measurements have been able to reveal deficiencies in the most sophisticated calculations of the three-body nuclear system, and indicate that further refinement in the treatment of their two- and/or three-body dynamics is required.
Published: 2014
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22. Measurement of 'pretzelosity' asymmetry of charged pion production in semi-inclusive deep inelastic scattering on a polarizedHe3target

Author: Jen-Chieh Peng, M. Osipenko, L. Yuan, K. Chirapatpimol, J. P. Chen, Y. X. Ye, Franco Garibaldi, Simon Širca, Y. Zhang, M. Huang, W. Kim, R. A. Lindgren, J. J. LeRose, J. Huang, G. M. Urciuoli, A. Kolarkar, A. Deur, X. Jiang, A. Saha, I. Vilardi, H. Ding, Salvatore Frullani, D. J. Margaziotis, M. M. Dalton, M. H. Shabestari, J. C. Cornejo, S. Riordan, R. Michaels, Xiaofeng Zhu, Douglas Higinbotham, M. K. Jones, C. Muñoz Camacho, B. Sawatzky, L. G. Tang, B. Zhao, X. Li, X. Zhan, X. Yan, M. Posik, X. Deng, Y. Li, Mauro Iodice, Abdurahim Rakhman, P. C. Bradshaw, William Bertozzi, T. Averett, S. Golge, D. McNulty, A. Camsonne, H. J. Lu, T. Holmstrom, David Hamilton, Pete Markowitz, H. Yao, Diana Parno, L. Guo, K. Wang, X. Zong, Chunhui Chen, Vincent Sulkosky, E. Long, S. Marrone, W. Chen, Z. E. Meziani, R. De Leo, Bogdan Wojtsekhowski, G. D. Cates, Yong Zhang, S. S. Stepanyan, A. Kelleher, B. Moffit, Vladimir Nelyubin, F. Cusanno, Nilanga Liyanage, Amrendra Narayan, Joseph M. Katich, P. Bosted, A. J. R. Puckett, Z. Ye, B. E. Norum, Mustafa Canan, Kalyan Allada, D. Gaskell, A. Shahinyan, Wolfgang Korsch, Fatiha Benmokhtar, E. Cisbani, Ronald Gilman, P. A. M. Dolph, Ronald Ransome, Xin Qian, L. El Fassi, Young Do Oh, C. Dutta, William A. Tobias, Yingxiao Wang, G. Jin, X. Zheng, S. K. Phillips, Shalev Gilad, C. W. de Jager, K. A. Aniol, H. F. Ibrahim, S. K. Nanda, Yujie Qiang, Dipangkar Dutta, Wouter Deconinck, R. Subedi, E. Chudakov, O. Glamazdin, Olfred Hansen, J. R. M. Annand, L. Y. Zhu, Haiyan Gao, and E. Schulte
Subjects: Quark, Physics, Nuclear and High Energy Physics, Particle physics, Scattering, media_common.quotation_subject, Deep inelastic scattering, Asymmetry, Nuclear physics, Pion, Distribution function, Neutron, Nuclear Experiment, Nucleon, media_common
Abstract: An experiment to measure single-spin asymmetries of semi-inclusive production of charged pions in deep-inelastic scattering on a transversely polarized $^{3}\mathrm{He}$ target was performed at Jefferson Laboratory in the kinematic region of $0.16lxl0.35$ and $1.4l{Q}^{2}l2.7$ ${\mathrm{GeV}}^{2}$. Pretzelosity asymmetries on $^{3}\mathrm{He}$, which are expressed as the convolution of the ${h}_{1T}^{\ensuremath{\perp}}$ transverse-momentum-dependent distribution functions and the Collins fragmentation functions in the leading order, were measured for the first time. Under the effective polarization approximation, we extracted the corresponding neutron asymmetries from the measured $^{3}\mathrm{He}$ asymmetries and cross-section ratios between the proton and $^{3}\mathrm{He}$. Our results show that both ${\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$ on $^{3}\mathrm{He}$ and on neutron pretzelosity asymmetries are consistent with zero within experimental uncertainties.
Published: 2014
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23. Measurement of the Target-Normal Single-Spin Asymmetry in Deep-Inelastic Scattering from the Reaction He3↑(e,e′)X

Author: W. Chen, S. Marrone, M. Osipenko, A. Kolarkar, Salvatore Frullani, Nilanga Liyanage, D. J. Margaziotis, E. Cisbani, T. Averett, M. Huang, X. Jiang, L. Guo, E. Long, Y. X. Ye, Wouter Deconinck, G. Jin, Bogdan Wojtsekhowski, H. Yao, X. Zheng, R. Subedi, F. Cusanno, A. Kelleher, S. K. Nanda, Yujie Qiang, William Bertozzi, X. Yan, Ronald Ransome, David Hamilton, Fatiha Benmokhtar, C. Dutta, Pete Markowitz, Xin Qian, M. H. Shabestari, P. A. M. Dolph, L. El Fassi, L. Zhu, R. De Leo, X. Deng, J. C. Cornejo, L. G. Tang, Yingxiao Wang, J. P. Chen, W. Kim, Shalev Gilad, D. McNulty, C. W. de Jager, K. A. Aniol, J. Huang, G. M. Urciuoli, Chunhui Chen, X. Zhan, Diana Parno, S. K. Phillips, X. Li, B. Moffit, Mauro Iodice, Wolfgang Korsch, Franco Garibaldi, S. S. Stepanyan, Simon Širca, Mustafa Canan, Kalyan Allada, Xiaofeng Zhu, A. Shahinyan, M. Posik, X. Zong, A. J. R. Puckett, Y. Li, P. Bosted, Z. E. Meziani, R. A. Lindgren, J. J. LeRose, A. Saha, M. M. Dalton, Jen-Chieh Peng, B. Sawatzky, Young Do Oh, I. Vilardi, H. Ding, P. C. Bradshaw, S. Riordan, L. Yuan, T. Holmstrom, H. F. Ibrahim, K. Chirapatpimol, Dipangkar Dutta, A. Camsonne, E. Chudakov, Vincent Sulkosky, A. Deur, R. Michaels, C. Muñoz Camacho, B. Zhao, Adam M. Tobias, G. D. Cates, Douglas Higinbotham, Yong Zhang, M. K. Jones, E. Schulte, O. Glamazdin, Vladimir Nelyubin, Olfred Hansen, J. R. M. Annand, K. Wang, Abdurahim Rakhman, Y. Zhang, Haiyan Gao, Amrendra Narayan, Joseph M. Katich, D. Gaskell, S. Golge, H. J. Lu, Ronald Gilman, Z. Ye, B. E. Norum, and Y. Zhao
Subjects: Physics, Range (particle radiation), Scattering, media_common.quotation_subject, General Physics and Astronomy, Deep inelastic scattering, Asymmetry, Nuclear physics, Cathode ray, High Energy Physics::Experiment, Born approximation, Nuclear Experiment, media_common, Sign (mathematics), Spin-½
Abstract: We report the first measurement of the target-normal single-spin asymmetry in deep-inelastic scattering from the inclusive reaction ^3He^↑ (e,e′) X on a polarized ^3He gas target. Assuming time-reversal invariance, this asymmetry is strictly zero in the Born approximation but can be nonzero if two-photon-exchange contributions are included. The experiment, conducted at Jefferson Lab using a 5.89 GeV electron beam, covers a range of 1.7 2 GeV, which is nonzero at the 2.89σ level. Our measured asymmetry agrees both in sign and magnitude with a two-photon-exchange model prediction that uses input from the Sivers transverse momentum distribution obtained from semi-inclusive deep-inelastic scattering.
Published: 2014
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24. Precision Measurement of the Neutron Twist-3 Matrix Elementd2n: Probing Color Forces

Author: H. F. Ibrahim, T. Averett, C. E. Hyde, B. Zhao, V. Mamyan, E. Chudakov, Bogdan Wojtsekhowski, F. Cusanno, Fatiha Benmokhtar, Whitney Armstrong, R. Michaels, A. Kolarkar, S. Choi, Y. Zhang, X. Yan, Xin Qian, Mustafa Canan, G. D. Cates, Kalyan Allada, Yiyang Zhang, Amrendra Narayan, Joseph M. Katich, G. B. Franklin, Young Do Oh, W. Troth, A. Saha, N. Muangma, Wouter Deconinck, A. Shahinyan, T. Holmstrom, M. Mihovilovic, M. H. Shabestari, Haiyan Gao, D. Wang, G. Jin, X. Zheng, R. A. Lindgren, L. Guo, J. J. LeRose, R. Subedi, Ronald Gilman, H. Yao, E. Long, S. Golge, M. Posik, X. Deng, Wolfgang Korsch, Douglas Higinbotham, A. Kelleher, M. Friend, S. K. Nanda, Yujie Qiang, X. Jiang, D. Flay, Y. X. Ye, P. Solvignon, D. McNulty, G. Kumbartzki, Nuruzzaman, Z. E. Meziani, Simon Širca, Chunhui Chen, F. Garibaldi, B. Moffit, B. Sawatzky, A. Deur, Yingxiao Wang, O. Glamazdin, Olfred Hansen, A. Camsonne, Z. Ye, B. E. Norum, Vincent Sulkosky, J. Gomez, Shalev Gilad, Jen-Chieh Peng, X. Zhan, L. Yuan, C. W. de Jager, Diana Parno, C. Dutta, William A. Tobias, J. P. Chen, J. Huang, A. Lukhanin, William Bertozzi, L. El Fassi, Nilanga Liyanage, Abdurahim Rakhman, Vladimir Nelyubin, M. M. Dalton, and S. Riordan
Subjects: Physics, Scattering, General Physics and Astronomy, High Energy Physics::Experiment, Neutron, Electron, Lattice QCD, Atomic physics, Spin structure, Deep inelastic scattering, Resonance (particle physics), Beam (structure)
Abstract: Double-spin asymmetries and absolute cross sections were measured at large Bjorken x (0.25≤x≤0.90), in both the deep-inelastic and resonance regions, by scattering longitudinally polarized electrons at beam energies of 4.7 and 5.9 GeV from a transversely and longitudinally polarized ^3He target. In this dedicated experiment, the spin structure function g^3He_2 was determined with precision at large x, and the neutron twist-3 matrix element dn2 was measured at ⟨Q2⟩ of 3.21 and 4.32 GeV^2/c^2, with an absolute precision of about 10^(−5). Our results are found to be in agreement with lattice QCD calculations and resolve the disagreement found with previous data at ⟨Q^2⟩=5 GeV^2/c^2. Combining d^n_2 and a newly extracted twist-4 matrix element f^n_2, the average neutron color electric and magnetic forces were extracted and found to be of opposite sign and about 30 MeV/fm in magnitude.
Published: 2014
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25. Probing the Repulsive Core of the Nucleon-Nucleon Interaction via theHe4(e,e′pN)Triple-Coincidence Reaction

Author: I. Korover, B. Zhao, Chunhui Chen, Karl Slifer, R. Shneor, Whitney Armstrong, Larry Weinstein, Salvatore Frullani, Franco Garibaldi, Wouter Deconinck, D. J. Margaziotis, A. Daniel, Simon Širca, N. Muangma, L. Selvy, J. P. Chen, G. Jin, X. Zheng, Bellini, S. K. Phillips, R. Subedi, E. Long, D. Wang, Ronald Gilman, John Arrington, E. Cisbani, Maxime Defurne, I. Yaron, P. Monaghan, Z. Ahmed, P. E. Reimer, Or Hen, H. Kang, O. Rondon-Aramayo, Bogdan Wojtsekhowski, T. Badman, Douglas Higinbotham, Z. E. Meziani, H. Baghdasaryan, M. Mihovilovič, T. Averett, William Bertozzi, Xin Qian, Marti Jimenez-Arguello A, Ping Zhu, Z. W. Zhao, Z. Ye, B. E. Norum, A. Saha, O. Glamazdin, K. Chirapatpimol, D. G. Meekins, Juliette Mammei, P. Solvignon, Ishay Pomerantz, Yujie Qiang, David Hamilton, Kalyan Allada, W. B. Yan, J. R. M. Annand, Pete Markowitz, M. Posik, Hashemi Shabestari M, D. Anez, K. Pan, X. Bai, Munoz Camacho C, W. U. Boeglin, B. D. Anderson, R. A. Lindgren, J. J. LeRose, Nuruzzaman, E. Piasetzky, H. Albataineh, Fatiha Benmokhtar, Nikolaos Sparveris, J. O. Hansen, Beck S, Yiyang Zhang, M. M. Dalton, N. Fomin, A. Beck, Punjabi, E. Fuchey, D. Gaskell, D. Flay, P. Aguilera, S. Riordan, E. Schulte, de Jager Cw, Paul Gueye, Donal Day, A. Camsonne, M. Huang, S. A. Wood, T. Holmstrom, C. Hanretty, J. Sjoegren, Kalantarians N, A. Kelleher, Abdurahim Rakhman, X. Qiu, R. Michaels, A. Shahinyan, Gu C, S. Iqbal, Guy Ron, J. Bittner, W. Tireman, J. Leckey, De Leo R, Sulkosky, Jie Zhang, R. Zielinski, J. W. Watson, Khandaker M, X. Zhan, M. Friend, Shalev Gilad, and K. A. Aniol
Subjects: Physics, Range (particle radiation), Proton, Nuclear Theory, General Physics and Astronomy, Momentum, Nuclear physics, Isospin, Neutron, Tensor, Atomic physics, Nuclear Experiment, Nucleon, Excitation
Abstract: We studied simultaneously the 4He(e,e'p), 4He(e,e'pp), and 4He(e,e'pn) reactions at Q2=2 [GeV/c]2 and xB >1, for a (e,e'p) missing-momentum range of 400 to 830 MeV/c. The knocked-out proton was detected in coincidence with a proton or neutron recoiling almost back to back to the missing momentum, leaving the residual A=2 system at low excitation energy. These data were used to identify two-nucleon short-range correlated pairs and to deduce their isospin structure as a function of missing momentum in a region where the nucleon-nucleon force is expected to change from predominantly tensor to repulsive. Neutron-proton pairs dominate the high-momentum tail of the nucleon momentum distributions, but their abundance is reduced as the nucleon momentum increases beyond ~500 MeV/c. The extracted fraction of proton-proton pairs is small and almost independent of the missing momentum in the range we studied. Our data are compared with ab-initio calculations of two-nucleon momentum distributions in 4He.
Published: 2014
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26. JLab Measurement of theHe4Charge Form Factor at Large Momentum Transfers

Author: A. Saha, Bogdan Wojtsekhowski, B. Moffit, J. Segal, T. Holmstrom, E. Kuchina, S. Frullani, Douglas Higinbotham, A. J. R. Puckett, Bumsung Lee, H. Yao, F. Garibaldi, R. Subedi, H. J. Lu, G. Lott, M. H. Shabestari, R. Michaels, M. Olson, E. Cisbani, B. Craver, S. Marrone, C. Dutta, A. Kievsky, E. Folts, Pete Markowitz, John Arrington, A. R. Baldwin, B. D. Anderson, R. A. Lindgren, W. M. Zhang, L. Zhu, B. E. Norum, R. Suleiman, A. Shahinyan, J. J. LeRose, J. P. Chen, A. Acha, D. J. Margaziotis, J. Huang, B. Hahn, S. Choi, E. Khrosinkova, P. Solvignon, E. Chudakov, Kalyan Allada, J. O. Hansen, X. Yan, Yingxiao Wang, Ronald Gilman, B. Sawatzky, G. Kumbartzki, G. G. Petratos, G. M. Urciuoli, Z. E. Meziani, A. Camsonne, J. Gomez, Michele Viviani, P. Decowski, X. Zheng, Nikolaos Sparveris, A. Kelleher, Sulkosky, M. Iodice, L. E. Marcucci, X. Jiang, O. Rondon, Xin Qian, D. G. Meekins, and A. T. Katramatou
Subjects: Physics, Elastic scattering, Nuclear reaction, Operator (physics), Nuclear Theory, Momentum transfer, Form factor (quantum field theory), General Physics and Astronomy, Observable, 7. Clean energy, Momentum, Nuclear physics, Nuclear Experiment, Wave function
Abstract: The electromagnetic (EM) form factors of the heliumisotopes are, along with the deuteron and tritium formfactors, the \observables of choice" [1] for testing thenucleon-meson standard model of the nuclear interac-tion and the associated EM current operator [2]. Theyprovide fundamental information on the internal struc-ture and dynamics of the light nuclei as they are, in asimple picture, convolutions of the ground state wavefunction with the EM form factors of the constituentnucleons. The theoretical calculations for these few-body observables are very sensitive to the model used forthe nuclear EM current operator, especially its meson-exchange-current (MEC) contributions. Relativistic cor-rections and possible admixtures of multi-quark states inthe nuclear wave function might also be relevant [2]. Ad-ditionally, at large momentum transfers, these EM formfactors may o er a unique opportunity to uncover a pos-sible transition in the description of elastic electron scat-tering on few-body nuclear systems, from meson-nucleonto quark-gluon degrees of freedom, as predicted by quark-dimensional scaling [3, 4].Experimentally, the few-body form factors are deter-mined from elastic electron-nucleus scattering studies us-ing high intensity beams, high density targets and large
Published: 2014
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27. Measurement of double-polarization asymmetries in the quasielastic he → 3 (e →,e′d) process

Author: M, Mihovilovič, G, Jin, E, Long, Y-W, Zhang, K, Allada, B, Anderson, J R M, Annand, T, Averett, W, Boeglin, P, Bradshaw, A, Camsonne, M, Canan, G D, Cates, C, Chen, J P, Chen, E, Chudakov, R, De Leo, X, Deng, A, Deltuva, A, Deur, C, Dutta, L, El Fassi, D, Flay, S, Frullani, F, Garibaldi, H, Gao, S, Gilad, R, Gilman, O, Glamazdin, J, Golak, S, Golge, J, Gomez, O, Hansen, D W, Higinbotham, T, Holmstrom, J, Huang, H, Ibrahim, C W, de Jager, E, Jensen, X, Jiang, M, Jones, H, Kang, J, Katich, H P, Khanal, A, Kievsky, P, King, W, Korsch, J, LeRose, R, Lindgren, H-J, Lu, W, Luo, L E, Marcucci, P, Markowitz, M, Meziane, R, Michaels, B, Moffit, P, Monaghan, N, Muangma, S, Nanda, B E, Norum, K, Pan, D, Parno, E, Piasetzky, M, Posik, V, Punjabi, A J R, Puckett, X, Qian, Y, Qiang, X, Qui, S, Riordan, A, Saha, P U, Sauer, B, Sawatzky, R, Schiavilla, B, Schoenrock, M, Shabestari, A, Shahinyan, S, Širca, R, Skibiński, J St, John, R, Subedi, V, Sulkosky, W A, Tobias, W, Tireman, G M, Urciuoli, M, Viviani, D, Wang, K, Wang, Y, Wang, J, Watson, B, Wojtsekhowski, H, Witała, Z, Ye, X, Zhan, Y, Zhang, X, Zheng, B, Zhao, and L, Zhu
Subjects: Physics and Astronomy (all)
Abstract: We present a precise measurement of double-polarization asymmetries in the ^{3}He[over →](e[over →],e^{'}d) reaction. This particular process is a uniquely sensitive probe of hadron dynamics in ^{3}He and the structure of the underlying electromagnetic currents. The measurements have been performed in and around quasielastic kinematics at Q^{2}=0.25(GeV/c)^{2} for missing momenta up to 270 MeV/c. The asymmetries are in fair agreement with the state-of-the-art calculations in terms of their functional dependencies on p_{m} and ω, but are systematically offset. Beyond the region of the quasielastic peak, the discrepancies become even more pronounced. Thus, our measurements have been able to reveal deficiencies in the most sophisticated calculations of the three-body nuclear system, and indicate that further refinement in the treatment of their two-and/or three-body dynamics is required.
Published: 2014

28. Recoil detection with a polarized He target

Author: H. de Vries, R. Ent, J. F. J. van den Brand, H. R. Poolman, Th. S. Bauer, D. Boersma, E. Six, P. Heimberg, M.F.M. Steenbakkers, Dominik Szczerba, D. W. Higinbotham, M. Ferro-Luzzi, D. Geurts, Igor Passchier, H. J. Bulten, B. E. Norum, Ricardo Alarcon, L.D. van Buuren, and M. Harvey
Subjects: Physics, Nuclear reaction, Nuclear and High Energy Physics, Luminosity (scattering theory), Physics::Instrumentation and Detectors, Detector, Polarimeter, Nuclear physics, Pion, Recoil, Atomic physics, Nuclear Experiment, Instrumentation, Storage ring, Beam (structure)
Abstract: The ultra-thin gas targets used in storage ring internal target experiments allow low energy, heavy nuclei to emerge from the target region. A detector capable of analyzing these nuclei provides unique access to many nuclear reactions. We report here the first use of such a detector in conjunction with a polarized 3 He internal target and a polarized electron beam. The results of using the detector as a luminosity monitor and as a polarimeter to measure the product of beam and target polarizations are presented. The ability to study coherent pion production via the reactions 3 He → ( e → , e ′ 3 He )π 0 and 3 He → ( e → , e ′ 3 H )π + is shown along with the ability of the detector to unambiguously separate the two- and three-body breakup channels of the reaction 3 He → ( e → , e ′p) .
Published: 2000
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29. The charge form factor of the neutron from

Author: Dominik Szczerba, J. Lang, H. Kolster, Z. L. Zhou, G. J. L. Nooren, I. A. Rachek, M. Ferro-Luzzi, C. W. de Jager, Kun Wang, D. M. Nikolenko, J. F. J. van den Brand, Douglas Higinbotham, Th. S. Bauer, B. E. Norum, Igor Passchier, H. R. Poolman, Ricardo Alarcon, L.D. van Buuren, Sander Klous, H. de Vries, M. C. Simani, H. J. Bulten, D. Boersma, and E. Six
Subjects: Physics, Nuclear and High Energy Physics, Interaction point, 010308 nuclear & particles physics, Electron, Polarization (waves), 7. Clean energy, 01 natural sciences, Deuterium, 0103 physical sciences, Pouch cell, Physics::Accelerator Physics, Neutron, Atomic physics, Nuclear Experiment, 010306 general physics, Beam energy, Electron scattering
Abstract: We report on the first measurement of spin-correlation parameters in quasifree electron scattering from vector-polarized deuterium. Polarized electrons were injected into an electron storage ring at a beam energy of 720 MeV. A Siberian snake was employed to preserve longitudinal polarization at the interaction point. Vector-polarized deuterium was produced by an atomic beam source and injected into an open-ended cylindrical cell, internal to the electron storage ring. The spin correlation parameter $A^V_{ed}$ was measured for the reaction $^2 \vec{\rm H}(\vec e,e^\prime n)p$ at a four-momentum transfer squared of 0.21~(GeV/$c$)$^2$ from which a value for the charge form factor of the neutron was extracted.
Published: 2000
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30. Electron scattering at NIKHEF with polarized beam and targets

Author: Igor Passchier, H. Kolster, R. Ent, J. Lang, D. Boersma, M. C. Simani, Z. L. Zhou, L.D. van Buuren, H. J. Bulten, Th. S. Bauer, B. L. Militsyn, C. W. de Jager, E. Six, B. E. Norum, Ricardo Alarcon, Dominik Szczerba, M.C. Bouwhuis, N. van Bakel, H. R. Poolman, M. Ferro-Luzzi, M. Harvey, J. J. M. Steijger, Sander Klous, D. W. Higinbotham, D. Geurts, J. F. J. van den Brand, T. Botto, P. Heimberg, and H. de Vries
Subjects: Physics, Nuclear and High Energy Physics, Scattering, Nuclear Theory, Particle accelerator, Electron, Mott scattering, law.invention, Nuclear physics, law, Physics::Accelerator Physics, Nucleon, Spin (physics), Electron scattering, Lepton
Abstract: We present the Internal Target Facility of the NIKHEF 900 MeV polarized electron storage ring. We give some results which illustrate the presently unique opportunity offered by this facility to study the spin structure of the nucleon, 2-body and 3-body system by the measurement of spin-dependent electron scattering observables.
Published: 1999
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31. A Compton backscattering polarimeter for measuring longitudinal electron polarization

Author: C. W. de Jager, N. Vodinas, B. E. Norum, N. Papadakis, D. W. Higinbotham, and Igor Passchier
Subjects: Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Polarimetry, FOS: Physical sciences, Electron, 01 natural sciences, High Energy Physics - Experiment, law.invention, High Energy Physics - Experiment (hep-ex), Optics, law, 0103 physical sciences, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Instrumentation, Computer Science::Databases, Physics, 010308 nuclear & particles physics, Scattering, business.industry, Astrophysics::Instrumentation and Methods for Astrophysics, Particle accelerator, Polarimeter, Instrumentation and Detectors (physics.ins-det), Polarization (waves), Cathode ray, Physics::Accelerator Physics, business, Storage ring
Abstract: Compton backscattering polarimetry provides a fast and accurate method to measure the polarization of an electron beam in a storage ring. Since the method is non-destructive, the polarization of the electron beam can be monitored during internal target experiments. For this reason, a Compton polarimeter has been constructed at NIKHEF to measure the polarization of the longitudinally polarized electrons which can be stored in the AmPS ring. The design and results of the polarimeter, the first Compton polarimeter to measure the polarization of a stored longitudinally polarized electron beam directly, are presented in this paper., 20 pages, 10 figures
Published: 1998
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32. Spin effects in medium-energy electron-He-3 scattering

Author: D. Geurts, H. J. Bulten, Igor Passchier, D. Szczerba, D. Boersma, M. Harvey, L.D. van Buuren, J. J. M. Steijger, H. de Vries, M. Van Der Putte, B. E. Norum, Tancredi Botto, Ricardo Alarcon, H. R. Poolman, C. W. de Jager, M. Ferro-Luzzi, P. Heimberg, J. F. J. van den Brand, Th. S. Bauer, E. Six, D. Highinbotham, R. Ent, and (Astro)-Particles Physics
Subjects: Nuclear and High Energy Physics, Hadron, Electron, OBSERVABLES, law.invention, Nuclear physics, law, Neutron, SDG 7 - Affordable and Clean Energy, Wave function, Spin (physics), Instrumentation, Computer Science::Databases, HE-3, Physics, FORM-FACTOR, POLARIZED ELECTRONS, Scattering, Particle accelerator, QUASI-ELASTIC SCATTERING, MODEL, NEUTRON, Atomic physics, Storage ring
Abstract: New physics can be accessed by scattering polarized electrons from a polarized He-3 internal gas target. It is discussed how the asymmetries for the reactions ((e) over right arrow, e''), ((e) over right arrow, e''p) ((e) over right arrow, e''n) ((e) over right arrow, e''d) and ((e) over right arrow, e''pn) may provide precise information on the S'' and the D-wave parts of the He-3 ground-state wave function, the neutron form factors, and the role of spin-dependent reaction mechanism effects. The experiment uses up to 900 MeV (polarized) electrons from the AmPS storage ring in Amsterdam, Netherlands, in combination with large acceptance electron and hadron detectors.
Published: 1998
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33. Gamma-Ray Production in a Storage Ring Free-Electron Laser

Author: M. Emamian, N.G. Gavrilov, H. R. Weller, Karl David Straub, C. R. Howell, R. Sachtschale, S. F. Mikhailov, P. Morcombe, Vladimir Litvinenko, Alexander Skrinsky, Nikolay Vinokurov, Patrick G. O'Shea, N. R. Roberson, Alex H. Lumpkin, N. Hower, John M. J. Madey, G. Swift, S.H. Park, Richard Shane Canon, B. E. Norum, V.M. Popik, G.N. Kulipanov, E. C. Schreiber, Igor Pinayev, P. Wang, B. Burnham, Bingxin Yang, Werner Tornow, M. Spraker, G. Y. Kurkin, M.G. Fedotov, and Ying Wu
Subjects: Photon, Materials science, business.industry, Astrophysics::High Energy Astrophysical Phenomena, Free-electron laser, Gamma ray, Physics::Optics, General Physics and Astronomy, Electron, Laser, law.invention, Optics, law, Optical cavity, Physics::Accelerator Physics, business, Beam (structure), Storage ring
Abstract: A nearly monochromatic beam of 100% linearly polarized g rays has been produced via Compton backscattering inside a free electron laser optical cavity. The beam of 12.2 MeV g rays was obtained by backscattering 379.4 nm free-electron laser photons from 500 MeV electrons circulating in a storage ring. A detailed description of the g-ray beam and the outlook for future improvements are presented. [S0031-9007(97)03322-X]
Published: 1997
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34. Spin asymmetries from16O(γ→,pπ−)nearΔresonance energies

Author: S. Hoblit, O. C. Kistner, A. M. Sandorfi, K. Hicks, B. E. Norum, M. Lucas, L. E. Wright, A. Cichocki, S.T. Thornton, R. A. Lindgren, A. Caracappa, J. Rapaport, C. S. Whisnant, R. M. Sealock, H. Baghaei, Frank X. Lee, L. C. Smith, C. E. Thorn, V. Gladyshev, T. Gresko, M. Khandaker, R. W. Finlay, G. Davenport, and L. Miceli
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Pion, Proton, Momentum transfer, Propagator, Sensitivity (control systems), Nuclear Experiment, Spin-½
Abstract: Spin asymmetries for the ${}^{16}\mathrm{O}(\stackrel{\ensuremath{\rightarrow}}{\ensuremath{\gamma}},p{\ensuremath{\pi}}^{\ensuremath{-}})$ reaction are reported for incident photon energies of 293 $\ifmmode\pm\else\textpm\fi{}$ 20 MeV, proton angles ranging from 28$\ifmmode^\circ\else\textdegree\fi{}$ to 140$\ifmmode^\circ\else\textdegree\fi{}$ (lab), and pion angles of 35$\ifmmode^\circ\else\textdegree\fi{}$ to 115$\ifmmode^\circ\else\textdegree\fi{}$. The data are compared with calculations in a quasifree plane-wave impulse approximation model. This model is in good agreement with the data at small momentum transfer $q$, but does not follow the trend of the data at large $q$. Sensitivity to the $\ensuremath{\Delta}$-nucleus potential and to modification of the $\ensuremath{\Delta}$ lifetime from nuclear medium effects are explored using a simple modification of the $\ensuremath{\Delta}$ propagator in the calculations.
Published: 1997
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35. Electroproduction of neutral pions on the proton

Author: W.J. Kasdorp, Tjeerd Ketel, M. A. van Uden, H. B. van den Brink, B. E. Norum, I. Bobeldijk, H. P. Blok, H. de Vries, G. E. Dodge, C. W. de Jager, M.J.M. van Sambeek, L. Lapikás, G. van der Steenhoven, and (Astro)-Particles Physics
Subjects: Nuclear physics, Nuclear reaction, Physics, Nuclear and High Energy Physics, Pion, Chiral perturbation theory, Hydrogen, chemistry, Cathode ray, chemistry.chemical_element, Electron, Invariant (physics), Coincidence
Abstract: The double-differential coincidence cross section for the reaction 1 H(e,e′π 0 )p has been measured at Q 2 = 0.1 (GeV/ c ) 2 for a range in the invariant energy W of 1 to 14 MeV above threshold in order to determine the s-wave multipoles E 0+ and L 0+ . The experiment was performed with a 525 MeV electron beam of the Amsterdam Pulse Stretcher and a cryogenic hydrogen target. The scattered electron and the recoiling proton were detected in two high-resolution magnetic spectrometers. By using a recent LET prediction for the relevant combinations of p-wave multipoles, values for E 0+ and L 0+ were extracted from the cos ϑ π ∗ and cos φ π ∗ dependent terms in the cross section. The data are compared to calculations from Chiral Perturbation Theory and from several Lagrangian models. All models give a fair to good description of L 0+ . ChPT gives also a good description of E 0+ , but the Lagrangian models tend to underestimate its value. The data for the angle-independent part of the cross section indicate that the value for the 2 M 1+ + M 1− combination of p-wave multipoles is overestimated by a recent ChPT prediction.
Published: 1997
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36. Single Spin Asymmetries of Inclusive Hadrons Produced in Electron Scattering from a Transversely Polarized $^3$He Target

Author: B. Sawatzky, X. Li, M. Posik, A. Camsonne, Xiaofeng Zhu, Mauro Iodice, Nilanga Liyanage, Vincent Sulkosky, Yingxiao Wang, T. Averett, J. P. Chen, Bogdan Wojtsekhowski, X. Zong, J. Huang, G. M. Urciuoli, Ronald Gilman, J. C. Cornejo, X. Yan, A. J. R. Puckett, Shalev Gilad, C. W. de Jager, R. A. Lindgren, J. J. LeRose, E. Cisbani, K. A. Aniol, W. Kim, M. H. Shabestari, Fatiha Benmokhtar, L. G. Tang, I. Vilardi, B. Moffit, A. Tobias, Wouter Deconinck, H. Ding, R. Michaels, Franco Garibaldi, Salvatore Frullani, Simon Širca, William Bertozzi, R. Subedi, F. Cusanno, G. D. Cates, A. Kolarkar, X. Deng, Amrendra Narayan, H. J. Lu, David Hamilton, Pete Markowitz, H. Yao, Joseph M. Katich, D. Gaskell, A. Deur, Haiyan Gao, C. Dutta, Y. Li, P. A. M. Dolph, R. De Leo, T. Holmstrom, D. McNulty, Arijit Saha, G. Jin, X. Zhan, Douglas Higinbotham, M. K. Jones, X. Zheng, O. Glamazdin, Olfred Hansen, J. R. M. Annand, S. Marrone, Chunhui Chen, Jen-Chieh Peng, S. K. Nanda, L. Guo, A. Shahinyan, M. Osipenko, Yujie Qiang, W. Chen, E. Long, L. Y. Zhu, K. Wang, Z. Ye, B. E. Norum, Y. Zhao, L. Yuan, Y. X. Ye, K. Chirapatpimol, Ronald Ransome, Y. Zhang, Diana Parno, Xin Qian, P. C. Bradshaw, A. Kelleher, E. Schulte, P. Bosted, M. Huang, S. Golge, X. Jiang, L. El Fassi, Z. E. Meziani, Wolfgang Korsch, D. J. Margaziotis, Young Do Oh, S. K. Phillips, C. Muñoz Camacho, B. Zhao, H. F. Ibrahim, Dipangkar Dutta, E. Chudakov, S. S. Stepanyan, Mustafa Canan, Kalyan Allada, Abdurahim Rakhman, Yong Zhang, Vladimir Nelyubin, M. M. Dalton, and S. Riordan
Subjects: Physics, Nuclear and High Energy Physics, Range (particle radiation), Proton, media_common.quotation_subject, Nuclear Theory, Hadron, High Energy Physics::Phenomenology, FOS: Physical sciences, Asymmetry, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), Pion, Neutron, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment, Electron scattering, Spin-½, media_common
Abstract: We report the first measurement of target single-spin asymmetries (A$_N$) in the inclusive hadron production reaction, $e~$+$~^3\text{He}^{\uparrow}\rightarrow h+X$, using a transversely polarized $^3$He target. The experiment was conducted at Jefferson Lab in Hall A using a 5.9-GeV electron beam. Three types of hadrons ($\pi^{\pm}$, $\text{K}^{\pm}$ and proton) were detected in the transverse hadron momentum range 0.54 $, Comment: Updated version, submitted to Phys. Rev. C
Published: 2013
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37. The TUNL-FELL inverse Compton γ-ray source as a nuclear physics facility

Author: C. P. Neuman, E. C. Schreiber, T. Scott Carman, Patrick G. O'Shea, N. Russell Roberson, Vladimir Litveninko, H. R. Weller, B. E. Norum, John M. J. Madey, and Carol Y. Scarlett
Subjects: Nuclear physics, Physics, Nuclear and High Energy Physics, Photon, Free-electron laser, Nuclear astrophysics, Physics::Accelerator Physics, Electron, Nucleon, Instrumentation, Collimated light, Beam (structure), Linear particle accelerator
Abstract: A new technique for producing an intense beam of polarized γ-rays is presented. This High-Intensity Gamma-ray Source (HIGS) will utilize the facilities of the new Duke Free Electron Laser Laboratory. This system includes the LINAC injector, the 1.3 GeV electron storage ring, and the OK-4 undulator.It will be shown that it is possible to tune the electron beam in a manner which allows the FEL photons to backscatter from an electron bunch, all within the ring. This leads to an intense beam of almost 100% linearly polarized γ-rays whose energy can be readily tuned from about 5 to greater than 200 MeV. Furthermore, beam energy spreads of less than 1% can be obtained by pure geometrical collimation. Details of the beam properties and background sources will be presented. It will be shown that this is an ideal beam for nuclear physics and nuclear astrophysics studies. One example of this which takes advantage of the flux, energy resolution and polarization of the beam, is the study of Δ 33 excitations in finite nuclei. These intense polarized beams will also make it possible to perform precision measurements of the nucleon polarizabilities. And we will see that studies in the vicinity of the photo-pion production threshold can provide crucial tests of many of the recent predictions (Low Energy Theorems) of Chiral Perturbation Theory. Our final example will show how the very intense beams available at low energies can be used to determine astrophysically important capture cross sections by measurements of the inverse reactions.
Published: 1996
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38. Negative pion photoproduction fromN15in the region of the Δ resonance

Author: W.H.A. Hesselink, Emil Hallin, T. Gresko, Jinsook Kim, J. Shaw, K. Keeter, J.C. Bergstrom, Hyun Tai Chung, J. M. Vogt, D. M. Skopik, B. E. Norum, H. Choi, T.P. Welch, H.S. Kaplan, H.B. van den Brink, J.H. Mitchell, P. Stoler, and T. Kobayashi
Subjects: Nuclear physics, Physics, Scattering cross-section, Nuclear and High Energy Physics, Pion, Impulse (physics), Photon energy, Atomic physics, Wave function, Delta baryon
Abstract: The differential cross section for the reaction {sup 15}N({gamma},{pi}{sup {minus}}){sup 15}O{sub gs} has been measured at a photon energy of 220 MeV. We find a discrepancy between our data and a calculation based on the distorted wave impulse approximation which uses phenomenological 1{ital p}-shell wave functions. A second calculation, in which higher-shell configurations are included in the wave functions, fails to correct the discrepancy and is even more at odds with the data.
Published: 1995
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39. Neutral-Pion Electroproduction on the Proton near Threshold

Author: G. J. L. Nooren, J. Konijn, J. A. Templon, J. J. M. Steijger, E. Jans, Mohsen Harakeh, I. Bobeldijk, Antonio Pellegrino, R.Y. de Vries, Nasser Kalantar-Nayestanaki, H. P. Blok, R. van der Meer, B. E. Norum, Tjeerd Ketel, C. W. de Jager, W.J. Kasdorp, J. A. P. Theunissen, G. van der Steenhoven, H. B. van den Brink, W.H.A. Hesselink, L. Lapikás, C. M. Spaltro, G. E. Dodge, N. de Jonge, H. de Vries, J. J. van Leeuwe, M. A. van Uden, D. G. Ireland, E. Passchier, P.K.A. de Witt Huberts, M.C. Bouwhuis, Other Research IHEF (IoP, FNWI), and Faculty of Science
Subjects: Physics, Particle physics, Chiral perturbation theory, Pion, Proton, Meson, Computer Science::Information Retrieval, Crossing, Hadron, General Physics and Astronomy, Elementary particle, Boson
Abstract: The double-differential coincidence cross section for the reaction {sup 1}H({ital e},{ital e}{prime}{ital p}){pi}{sup 0} has been measured at {ital Q}{sup 2}=0.1(GeV/{ital c}){sup 2} in a range in the invariant mass of 2--14 MeV above threshold. From the angular dependence of the data values of the pion {ital s}-wave multipoles {ital E}{sub 0+} and {ital L}{sub 0+} have been extracted. The results are compared to predictions from chiral perturbation theory and models based on an effective Lagrangian. None of the models is able to describe both the {ital E}{sub 0+} and the {ital L}{sub 0+} multipoles.
Published: 1995
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40. The 13C(γ,π−)13N reaction at Eγ≈ 184 MeV (Tπ ≈ 41 MeV)

Author: H. B. van den Brink, T. Gresko, T. P. Welch, Emil Hallin, T. Kobayashi, W.H.A. Hesselink, B. E. Norum, P. Stoler, Hyun Tai Chung, D. M. Skopik, John C. Mitchell, H. Choi, J. Shaw, J. M. Vogt, and H. P. Blok
Subjects: Nuclear physics, Physics, Nuclear reaction, Nuclear and High Energy Physics, Cross section (physics), Particle physics, Pion, Nuclear Experiment, Differential (mathematics)
Abstract: Differential cross sections for the 13 C( γ , π − ) 13 N reaction at E γ ≈ 184 MeV ( T π ≈ 41 MeV) were measured with the Saskatoon tagged-photon facility and two range-telescope detectors. Data were obtained at pion angles of 45°, 60°, 80° and 100°, with emphasis on the forward angles, where the cross section shows a strong rise. The present data, together with existing ones at larger angles, are compared to several theoretical calculations.
Published: 1995
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41. Inelastic electron scattering fromO18at backward angles

Author: M.M. Niboh, B. E. Norum, D. M. Manley, B. L. Clausen, R. A. Lindgren, R.M. Sellers, B. L. Berman, M. Farkhondeh, and DS Weerasundara
Subjects: Physics, Nuclear reaction, Nuclear and High Energy Physics, Scattering, Momentum transfer, Form factor (quantum field theory), Center (category theory), Inelastic electron scattering, State (functional analysis), Inelastic scattering, Atomic physics
Abstract: Discrete states in $^{18}\mathrm{O}$ up to 25 MeV of excitation were studied by inelastic electron scattering. The measurements were performed at the Bates Linear Accelrator Center at 110\ifmmode^\circ\else\textdegree\fi{} and 140\ifmmode^\circ\else\textdegree\fi{}, and at momentum transfers ranging from about 1.2 to 2.5 ${\mathrm{fm}}^{\mathrm{\ensuremath{-}}1}$. A number of the states discussed here have not been observed previously. Form-factor measuremetns are presented for eight ${4}^{\mathrm{\ensuremath{-}}}$ candidates and for two ${6}^{\mathrm{\ensuremath{-}}}$ candidates. The strongest ${4}^{\mathrm{\ensuremath{-}}}$ state has T=2 and was observed at 22.40 MeV. Good T=2 ${4}^{\mathrm{\ensuremath{-}}}$ candidates were found at 18.68 and 20.36 MeV, and good T=1 ${4}^{\mathrm{\ensuremath{-}}}$ candidates were found at 8.52 and 12.99 MeV; the strongest ${6}^{\mathrm{\ensuremath{-}}}$ candidate was found at 14.17 MeV. Form-factor measurements are also presented for several ${2}^{\mathrm{\ensuremath{-}}}$ candidates. The M2 form factor for the lowest ${2}^{\mathrm{\ensuremath{-}}}$ state at 5.53 MeV is similar in shape to that for the lowest ${2}^{\mathrm{\ensuremath{-}}}$ state in $^{16}\mathrm{O}$, but is weaker in strength. Finally, form-factor measurements are presented for several high-lying normal-parity states, including strong excitations at 9.36, 9.71, 11.67, and 17.02 MeV.
Published: 1995
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42. Beam-Target Double-Spin AsymmetryALTin Charged Pion Production from Deep Inelastic Scattering on a Transversely PolarizedHe3Target at1.4<Q2<2.7 GeV2

Author: Jen-Chieh Peng, Wolfgang Korsch, L. Yuan, L. G. Tang, Nilanga Liyanage, K. Chirapatpimol, S. K. Nanda, Yujie Qiang, A. Shahinyan, Z. E. Meziani, H. J. Lu, X. Yan, Salvatore Frullani, Y. Li, D. J. Margaziotis, E. Cisbani, R. A. Lindgren, J. J. LeRose, A. Deur, L. Guo, E. Long, B. Zhao, X. Zhan, Ronald Gilman, I. Vilardi, H. Ding, Wouter Deconinck, A. Kelleher, G. Jin, R. Subedi, Diana Parno, X. Zheng, Bogdan Wojtsekhowski, Ronald Ransome, P. Bosted, Z. Ye, B. E. Norum, Xin Qian, Y. Zhang, W. Kim, Franco Garibaldi, B. Sawatzky, P. A. M. Dolph, Simon Širca, R. Michaels, J. C. Cornejo, C. Dutta, W. Chen, Douglas Higinbotham, M. K. Jones, B. Moffit, A. Camsonne, F. Cusanno, Vincent Sulkosky, X. Zong, A. J. R. Puckett, L. El Fassi, Xiaofeng Zhu, S. Golge, X. Li, C. Muñoz Camacho, K. Wang, Yingxiao Wang, M. Huang, G. D. Cates, M. Posik, Shalev Gilad, C. W. de Jager, X. Jiang, K. A. Aniol, M. H. Shabestari, M. Osipenko, Mauro Iodice, Y. X. Ye, William Bertozzi, H. F. Ibrahim, S. Marrone, Amrendra Narayan, Joseph M. Katich, D. Gaskell, David Hamilton, Pete Markowitz, Dipangkar Dutta, X. Deng, R. De Leo, J. P. Chen, S. S. Stepanyan, Mustafa Canan, Chen Chen, Kalyan Allada, T. Holmstrom, D. McNulty, E. Chudakov, T. Averett, J. Huang, G. M. Urciuoli, Young Do Oh, A. Tobias, Fatiha Benmokhtar, Abdurahim Rakhman, A. Kolarkar, M. M. Dalton, S. Riordan, A. Saha, Yong Zhang, Vladimir Nelyubin, Haiyan Gao, P. C. Bradshaw, S. K. Phillips, O. Glamazdin, Olfred Hansen, J. R. M. Annand, L. Y. Zhu, E. Schulte, and H. Yao
Subjects: Quark, Physics, Particle physics, 010308 nuclear & particles physics, Scattering, media_common.quotation_subject, General Physics and Astronomy, Parton, Electron, Deep inelastic scattering, 01 natural sciences, Asymmetry, Nuclear physics, Pion, 0103 physical sciences, High Energy Physics::Experiment, Neutron, Nuclear Experiment, 010306 general physics, media_common
Abstract: We report the first measurement of the double-spin asymmetry A_(LT) for charged pion electroproduction in semi-inclusive deep-inelastic electron scattering on a transversely polarized ^3He target. The kinematics focused on the valence quark region, 0.16
Published: 2012
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43. Methods for Optical Calibration of the BigBite Hadron Spectrometer

Author: J. P. Chen, J. Huang, Guy Ron, M. H. Shabestari, Yujie Qiang, S. Riordan, S. Širca, J. W. Watson, B. E. Norum, Douglas Higinbotham, J. R. M. Annand, R.W. Chan, Nilanga Liyanage, David Hamilton, Wolfgang Korsch, R. Michaels, J. O. Hansen, K. Chirapatpimol, T. Averett, A. Shahinyan, G. Rosner, Kalyan Allada, B. Sawatzky, X. Jiang, Y.-W. Zhang, Xin Qian, Shalev Gilad, C. W. de Jager, B. Moffit, B. D. Anderson, P. Monaghan, Vladimir Nelyubin, E. Long, R. A. Lindgren, J. J. LeRose, M. Mihovilovič, G. Jin, A. Camsonne, Vincent Sulkosky, E. Piasetzky, R. Shneor, and R. Subedi
Subjects: Physics, Nuclear and High Energy Physics, Particle physics, Spectrometer, Hadron, Detector, FOS: Physical sciences, Nuclear physics, Particle type, Optical calibration, Singular value decomposition, Nuclear Experiment (nucl-ex), Nuclear Experiment, Instrumentation
Abstract: The techniques for optical calibration of Jefferson Lab's large-acceptance magnetic hadron spectrometer, BigBite, have been examined. The most consistent and stable results were obtained by using a method based on singular value decomposition. In spite of the complexity of the optics, the particles' positions and momenta at the target have been precisely reconstructed from the coordinates measured in the detectors by means of a single back-tracing matrix. The technique is applicable to any similar magnetic spectrometer and any particle type. For 0.55 GeV/c protons, we have established the vertex resolution of 1.2 cm, angular resolutions of 7 mrad and 16 mrad (in-plane and out-of-plane, respectively), and a relative momentum resolution of 1.6%., Comment: 26 pages, 13 figures
Published: 2012
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44. Measurement of the absolute and differential cross sections for7Li(γ,n0)6Li

Author: Ward Wurtz, M. W. Ahmed, S. Stave, S. Kucuker, H. R. Weller, B. Sawatzky, R. E. Pywell, and B. E. Norum
Subjects: Physics, Nuclear and High Energy Physics, Photon, Linear polarization, Photon polarization, Nuclear cross section, Photon energy, Atomic physics, Ground state, Polarization (waves)
Abstract: We have measured the cross section of the photoneutron reaction channel ${}^{7}\text{Li}+\ensuremath{\gamma}{\ensuremath{\rightarrow}}^{6}\text{Li(g.s.)}+n$ where the progeny nucleus is the ground state of ${}^{6}$Li. We obtained the absolute cross section at photon energies 10, 11, 12, 13, 15, 20, 25, 30, and 35 MeV and also the dependence of the cross section on polar angle for all but the highest photon energy. For the energies 10 to 15 MeV we were able to use linearly polarized photons to obtain the dependence of the cross section on the photon polarization.
Published: 2011
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45. Single Spin Asymmetries in Charged Pion Production from Semi-Inclusive Deep Inelastic Scattering on a Transversely PolarizedHe3Target atQ2=1.4–2.7 GeV2

Author: A. Kolarkar, M. Huang, X. Jiang, C. Dutta, M. Osipenko, T. Averett, H. Yao, W. Chen, Abdurahim Rakhman, L. G. Tang, Bogdan Wojtsekhowski, Y. X. Ye, X. Zhan, X. Yan, O. Glamazdin, Olfred Hansen, J. R. M. Annand, Fatiha Benmokhtar, D. McNulty, Arijit Saha, Diana Parno, W. Kim, Nilanga Liyanage, Wouter Deconinck, R. Subedi, D. J. Margaziotis, Salvatore Frullani, Chunhui Chen, P. Bosted, Yingxiao Wang, Yong Zhang, Shalev Gilad, Vladimir Nelyubin, Wolfgang Korsch, M. M. Dalton, Yuxiang Zhao, E. Cisbani, C. W. de Jager, K. A. Aniol, L. Guo, S. Riordan, E. Long, L. Y. Zhu, M. H. Shabestari, A. Kelleher, X. Li, S. K. Phillips, Mauro Iodice, E. Schulte, J. P. Chen, X. Deng, A. Shahinyan, G. Jin, X. Zheng, J. Huang, G. M. Urciuoli, S. K. Nanda, P. A. M. Dolph, Yujie Qiang, J. C. Cornejo, A. Tobias, William Bertozzi, S. Marrone, David Hamilton, Pete Markowitz, R. De Leo, Franco Garibaldi, Simon Širca, Ronald Ransome, S. S. Stepanyan, Xin Qian, Mustafa Canan, Kalyan Allada, B. Moffit, L. El Fassi, Xiaofeng Zhu, Z. E. Meziani, R. A. Lindgren, J. J. LeRose, I. Vilardi, H. Ding, B. Sawatzky, G. D. Cates, A. Camsonne, Vincent Sulkosky, Y. Li, X. Zong, R. Michaels, H. F. Ibrahim, C. Muñoz Camacho, Dipangkar Dutta, B. Zhao, A. J. R. Puckett, Haiyan Gao, E. Chudakov, T. Holmstrom, Young Do Oh, F. Cusanno, Douglas Higinbotham, M. K. Jones, A. Deur, M. Posik, P. C. Bradshaw, K. Wang, H. J. Lu, Jen-Chieh Peng, Ronald Gilman, L. Yuan, K. Chirapatpimol, Z. Ye, B. E. Norum, Y. Zhang, Amrendra Narayan, Joseph M. Katich, D. Gaskell, and S. Golge
Subjects: Physics, Particle physics, Proton, 010308 nuclear & particles physics, Hadron, General Physics and Astronomy, Inelastic scattering, Deep inelastic scattering, 01 natural sciences, Baryon, Nuclear physics, Pion, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment, 010306 general physics, Nucleon, Lepton
Abstract: We report the first measurement of target single spin asymmetries in the semi-inclusive ^3He(e,e^′π^±)X reaction on a transversely polarized target. The experiment, conducted at Jefferson Lab using a 5.9 GeV electron beam, covers a range of 0.16
Published: 2011
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46. Probing Quark-Gluon Interactions with Transverse Polarized Scattering

Author: L. G. Tang, D. McNulty, C. Yan, R. Asaturyan, Y. Prok, D. G. Crabb, P. McKee, L. Gan, J. Roche, Rolf Ent, M. Khandaker, C. Carasco, P. E. Bosted, J. Reinhold, D. G. Meekins, L. Coman, L. Cole, J. A. Dunne, H. Mkrtchyan, Y. Liang, Brian Raue, S. Stepanyan, J. Yun, Dinko Pocanic, W. F. Vulcan, D. Kiselev, K. Normand, R. D. Carlini, Karl Slifer, B. E. Norum, J. P. Chen, Ingo Sick, D. Gaskell, R. A. Lindgren, Andreas Klein, G. Testa, L. Yuan, A. Ahmidouch, M. Elaasar, J. Jourdan, F. R. Wesselmann, M. K. Jones, F. Bloch, B. Hu, I. Niculescu, Geoffrey Smith, Glen A. Warren, A. Aghalaryan, M. Zeier, Rakhsha Nasseripour, L. H. Kramer, O. Rondon, K. Wang, J. Cha, H. C. Fenker, S. Danagoulian, J. Gomez, J. Lichtenstadt, M. E. Christy, N. Savvinov, H. Zhu, Curtis Smith, Donal Day, S. Tajima, C. D. Keith, S. A. Wood, W.U. Boeglin, D. J. Mack, M. L. Seely, B. Sawatzky, C. E. Keppel, and Emil Frlez
Subjects: Physics, Quark, Quantum chromodynamics, Particle physics, Nuclear Theory, High Energy Physics::Phenomenology, Momentum transfer, FOS: Physical sciences, General Physics and Astronomy, Inelastic scattering, Matrix (mathematics), Isospin, High Energy Physics::Experiment, Sum rule in quantum mechanics, Nuclear Experiment (nucl-ex), Twist, Nuclear Experiment
Abstract: We have extracted QCD matrix elements from our data on double polarized inelastic scattering of electrons on nuclei. We find the higher twist matrix element \tilde{d_2}, which arises strictly from quark- gluon interactions, to be unambiguously non zero. The data also reveal an isospin dependence of higher twist effects if we assume that the Burkhardt-Cottingham Sum rule is valid. The fundamental Bjorken sum rule obtained from the a0 matrix element is satisfied at our low momentum transfer., formerly "Nachtmann Moments of the Proton and Deuteron Spin Structure Functions"
Published: 2010
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47. Electroproduction ofπ0on the proton near threshold

Author: B. E. Norum, M. Deady, L. Lapikás, J.C. Bergstrom, C. W. de Jager, H. B. van den Brink, J. Wesseling, H. P. Blok, T.P. Welch, P.H. Karen, E. Jans, H. de Vries, and J. H. Mitchell
Subjects: Nuclear reaction, Physics, Particle physics, Pion, Proton, Meson, Hadron, General Physics and Astronomy, Elementary particle, Atomic physics, Bar (unit), Boson
Abstract: The electroproduction of {pi}{sup 0} on the proton was measured from 0 to 2.5 MeV above threshold for virtual-photon 4-momenta of {minus}0.05 and {minus}0.1 (GeV/{ital c}){sup 2}. The sum of the lowest-order contributing multipoles, {ital a}{sub 0}={vert bar}{ital E}{sub 0+}{vert bar}{sup 2}{minus}{epsilon}{sub {ital L}}{vert bar}{ital L}{sub 0+}{vert bar}{sup 2}, was determined with a precision an order of magnitude better than previously possible. Our results for {ital a}{sub 0} are consistent with present calculations. Our extracted value for {vert bar}{ital L}{sub 0+}{vert bar}{sup 2} at the photon point'' is in agreement with recent predictions.
Published: 1992
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48. High-Resolution Spectroscopy ofNΛ16by Electroproduction

Author: P. E. Ulmer, B. Kross, Maryam Moteabbed, J. Reinhold, R. Roche, Pavlo Baturin, H. Benaoum, H. F. Ibrahim, E. Voutier, Toshinobu Miyoshi, Bogdan Wojtsekhowski, B. Craver, E. Chudakov, P. Ambrozewicz, J. P. Chen, F. Giuliani, P.Y. Bertin, Y. Okasyasu, Olivier Gayou, S. K. Nanda, F. Cusanno, D. Hayes, C. E. Hyde, Yujie Qiang, P. E. Reimer, A. Deur, K. I. Blomqvist, M. Sotona, W. U. Boeglin, T. Holmstrom, G. M. Urciuoli, P. Solvignon, Kent Paschke, Alexandre Camsonne, P. Monaghan, L. J. Kaufman, H. Breuer, C. F. Perdrisat, S. Marrone, Eugenio Nappi, A. Acha, R. Michaels, C. Zorn, K. Kino, D. J. Margaziotis, L. Lagamba, C. Munoz Camacho, Pete Markowitz, E. Folts, A. J. Sarty, S. Frullani, Vladimir Nelyubin, D. J. Millener, A. Saha, M. Gricia, R. De Leo, Brian Raue, Simon Širca, M. Lucentini, F. Garibaldi, Tohru Suzuki, J. Segal, E. Cisbani, Mauro Iodice, P. Bydzovsky, H. Ueno, R. Fratoni, B. Reitz, Douglas Higinbotham, J. Gomez, R. Snyder, X. Jiang, X. Zeng, C. W. de Jager, R. J. Feuerbach, P. Veneroni, E. Piasetzky, C. Ferdi, K. A. Aniol, Bryan J. Moffit, Jaideep Singh, Seonho Choi, K. McCormick, R. Subedi, R. A. Lindgren, J. J. LeRose, V. Sulkosky, L. Coman, J.-O. Hansen, B. E. Norum, C. C. Chang, Z. E. Meziani, P. Brindza, V. A. Punjabi, G. de Cataldo, A. Shahinyan, F. Santavenere, S. Colilli, and V. M. Rodriguez
Subjects: Physics, 010308 nuclear & particles physics, Binding energy, General Physics and Astronomy, Sigma, Halo nucleus, Lambda, Hypernucleus, 01 natural sciences, 0103 physical sciences, Atomic physics, Thin film, 010306 general physics, Spectroscopy, Energy (signal processing)
Abstract: An experimental study of the 16O(e,e'K^+)16N_Lambda reaction has been performed at Jefferson Lab. A thin film of falling water was used as a target. This permitted a simultaneous measurement of the p(e,e'K^+)Lambda,Sigma_0 exclusive reactions and a precise calibration of the energy scale. A ground-state binding energy of 13.76 +/- 0.16 MeV was obtained for 16N_Lambda with better precision than previous measurements on the mirror hypernucleus 16O_Lambda. Precise energies have been determined for peaks arising from a Lambda in s and p orbits coupled to the p_{1/2} and p_{3/2} hole states of the 15N core nucleus.
Published: 2009
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49. Effective interaction forCa40(p,p’) atEp=318 MeV

Author: B. E. Norum, P. Karen, M. A. Khandaker, James J. Kelly, B. S. Flanders, P. Welch, S. Nanda, S. D. Hyman, P. Boberg, Arijit Saha, A. E. Feldman, and H. Seifert
Subjects: Physics, Nuclear reaction, Elastic scattering, Nuclear and High Energy Physics, symbols.namesake, Pauli exclusion principle, Scattering, symbols, Inelastic scattering, Atomic physics, Nuclear matter, Wave function, Excitation
Abstract: Differential cross sections and analyzing powers have been measured for the excitation by 318 MeV protons of states of {sup 40}Ca below 7.2 MeV. The data for those normal-parity excitations for which transition densities are available from electroexcitation measurements are analyzed in terms of medium modifications to the nucleon-nucleon interaction. We find that the empirical effective interaction previously fitted to {sup 16}O({ital p},{ital p}{prime}) data at the same energy predicts {sup 40}Ca({ital p},{ital p}{prime}) very well. Density-dependent modifications of the effective interaction fitted to data for {sup 40}Ca or {sup 16}O, either independently or simultaneously, are virtually identical. The density dependence of the empirical interaction is considerably stronger than that of interactions based upon nonrelativistic nuclear matter theory and persists to lower density. The most significant differences are that the empirical interaction has a stronger repulsive core and that absorption is enhanced at high density, contrary to expectations based upon Pauli blocking. We also find substantial suppression of the spin-orbit interaction at low density and enhancement at high density. Nevertheless, the independence of the effective interaction from the target supports the concept of local nuclear matter density. We also find that optical potentials based upon the empirical effective interaction aremore » very similar to Schroedinger-equivalent potentials based upon a relativistic impulse approximation model, suggesting that the empirical density dependence is similar to the equivalent density dependence that arises from elimination of lower components from Dirac wave functions. Finally, the results are compared with global optical potentials from Dirac phenomenology.« less
Published: 1991
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50. Neutron and proton transition densities fromS32,34(p,p’) atEp=318 MeV. I. Isoscalar densities forS32

Author: P. Karen, James J. Kelly, S. Nanda, H. Seifert, Khandaker, P. Boberg, B. E. Norum, Arijit Saha, B. S. Flanders, S. D. Hyman, A. E. Feldman, and P. Welch
Subjects: Nuclear reaction, Physics, Elastic scattering, Nuclear and High Energy Physics, Proton, Scattering, Isoscalar, Neutron, Position and momentum space, Inelastic scattering, Atomic physics, Neutron density
Abstract: Differential cross sections and analyzing powers for low-lying states of $^{34}\mathrm{S}$ were measured using 318 MeV protons. Neutron transition densities for the ${2}_{1}^{+}$ and ${2}_{2}^{+}$ states were fitted to the data using general expansions which permit evaluation of uncertainties due to statistical and normalization errors, penetrability and distortion, and incompleteness in momentum space. We find that the experimental densities agree well with the shell model for the first ${2}^{+}$ state, but that the neutron density for the second ${2}^{+}$ state is distinctly different in shape. We also find ${\mathit{M}}_{\mathit{n}}$/${\mathit{M}}_{\mathit{p}}$=+0.27(6) for the ${2}_{2}^{+}$ state, in qualitative agreement with electromagnetic results for A=34 but in marked disagreement with the shell-model prediction of ${\mathit{M}}_{\mathit{n}}$/${\mathit{M}}_{\mathit{p}}$=-0.61. A detailed analysis of earlier data for 650 MeV, originally described as qualitatively consistent with the shell model, is also presented and shows that these data are more consistent with the present results. The shape of the isoscalar density for the ${2}_{2}^{+}$ state of $^{34}\mathrm{S}$ cannot be reproduced with the sd shell, supplemented by surface-peaked core polarization, but can be reproduced if an empirical (1f${)}^{2}$ contribution is admitted. Shell-model calculations were performed for other ${2}^{+}$ and ${4}^{+}$ states of $^{34}\mathrm{S}$, but give cross sections well below the (p,p') data for all but the lowest ${2}^{+}$ state. The data for the lowest ${1}^{\mathrm{\ensuremath{-}}}$, ${3}^{\mathrm{\ensuremath{-}}}$, and ${5}^{\mathrm{\ensuremath{-}}}$ states in both $^{34}\mathrm{S}$ and $^{32}\mathrm{S}$ are very similar.
Published: 1991
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