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Full-Text Articles in Physics
Exclusive 𝝅⁻ Electroproduction Off The Neutron In Deuterium In The Resonance Region, Y. Tian, R. W. Gothe, V. I. Mokeev, G. Hollis, M. J. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, L. Barion, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. Biselli, F. Bossù, S. Boiarinov, M. Bondì, J. Zhang, Et Al., The Clas Collaboration
Exclusive 𝝅⁻ Electroproduction Off The Neutron In Deuterium In The Resonance Region, Y. Tian, R. W. Gothe, V. I. Mokeev, G. Hollis, M. J. Amaryan, W. R. Armstrong, H. Atac, H. Avakian, L. Barion, M. Battaglieri, I. Bedlinskiy, B. Benkel, F. Benmokhtar, A. Bianconi, L. Biondo, A. Biselli, F. Bossù, S. Boiarinov, M. Bondì, J. Zhang, Et Al., The Clas Collaboration
Physics Faculty Publications
New results for the exclusive and quasifree cross sections off neutrons bound in deuterium 𝛾vn(p) → pπ− (p) are presented over a wide final state hadron angle range with a kinematic coverage of the invariant mass (W) up to 1.825 GeV and the four-momentum transfer squared (Q2) from 0.4 to 1.0 GeV2. The exclusive structure functions were extracted and their Legendre moments were obtained. Final-state-interaction contributions have been kinematically separated from the extracted quasifree cross sections off bound neutrons solely based on the analysis of the experimental data. These new results will serve as …
Measuring Recoiling Nucleons From The Nucleus With The Future Electron Ion Collider, Florian Hauenstein, A. Jentsch, J. R. Pybus, A. Kiral, M. D. Baker, Y. Furletova, O. Hen, D. W. Higinbotham, Charles Hyde, V. Morozov, D. Romanov, Lawrence B. Weinstein
Measuring Recoiling Nucleons From The Nucleus With The Future Electron Ion Collider, Florian Hauenstein, A. Jentsch, J. R. Pybus, A. Kiral, M. D. Baker, Y. Furletova, O. Hen, D. W. Higinbotham, Charles Hyde, V. Morozov, D. Romanov, Lawrence B. Weinstein
Physics Faculty Publications
Short range correlated nucleon-nucleon (NN) pairs are an important part of the nuclear ground state. They are typically studied by scattering an electron from one nucleon in the pair and detecting its spectator correlated partner (“spectator-nucleon tagging”). The Electron Ion Collider (EIC) should be able to detect these nucleons, since they are boosted to high momentum in the laboratory frame by the momentum of the ion beam. To determine the feasibility of these studies with the planned EIC detector configuration, we have simulated quasielastic scattering for two electron and ion beam energy configurations: 5 GeV e− and 41 …
Determination Of The Argon Spectral Function From (E, E'P) Data, Jefferson Lab Hall A Collaboration, L. Jiang, A.M. Ankowski, D. Abrams, Florian Hauenstein, Charles Hyde, S. Wood, Z. Ye, J. Zhang, Et Al.
Determination Of The Argon Spectral Function From (E, E'P) Data, Jefferson Lab Hall A Collaboration, L. Jiang, A.M. Ankowski, D. Abrams, Florian Hauenstein, Charles Hyde, S. Wood, Z. Ye, J. Zhang, Et Al.
Physics Faculty Publications
The E12-14-012 experiment, performed in Jefferson Lab Hall A, has measured the (e,e′p) cross section in parallel kinematics using a natural argon target. Here, we report the full results of the analysis of the data set corresponding to beam energy 2.222 GeV, and spanning the missing momentum and missing energy range 15 ≲ pm ≲ 300 MeV /c and 12 ≲ Em ≲ 80 MeV. The reduced cross section, determined as a function of pm and Em with ≈ 4% accuracy, has been fitted using the results of Monte Carlo simulations involving a model spectral function and …
Polarized Structure Function ΣLt' From 𝜋⁰P Electroproduction Data In The Resonance Region At 0.2 Gev² < Q² < 1.0 Gev², E. L. Isupov, V. D. Burkert, A. A. Golubenko, K. Joo, N. S. Markov, V. I. Mokeev, L. C. Smith, N. Zachariou, W. R. Armstrong, H. Atac, Et Al
Polarized Structure Function ΣLt' From 𝜋⁰P Electroproduction Data In The Resonance Region At 0.2 Gev² < Q² < 1.0 Gev², E. L. Isupov, V. D. Burkert, A. A. Golubenko, K. Joo, N. S. Markov, V. I. Mokeev, L. C. Smith, N. Zachariou, W. R. Armstrong, H. Atac, Et Al
Physics Faculty Publications
The first results on the σLT′ structure function in exclusive π0p electroproduction at invariant masses of the final state of 1.5GeV < W < 1.8 GeV and in the range of photon virtualities 0.4 GeV2 < Q2 < 1.0 GeV2 were obtained from data on beam spin asymmetries and differential cross sections measured with the CLAS detector at Jefferson Lab. The Legendre moments determined from the σLT′ structure function have demonstrated sensitivity to the contributions from the nucleon resonances in the second and third resonance regions. These new data on the beam spin asymmetries in π0p electroproduction extend the opportunities for the extraction of the nucleon resonance electro-excitation amplitudes in …
Measurement Of The Nucleon FN₂/FP₂ Structure Function Ratio By The Jefferson Lab Marathon Tritium/Helium-3 Deep Inelastic Scattering Experiment, D. Abrams, H. Albataineh, B. S. Aljawrneh, S. Alsalmi, D. Androic, K. Aniol, W. Armstrong, J. Arrington, H. Atac, T. Averett, C. Ayerbe Gayoso, X. Bai, J. Bane, J. Barcus, A. Beck, V. Bellini, H. Bhatt, D. Bhetuwal, D. Biswas, D. Blyth, W. Boeglin, D. Bulumulla, Et Al.
Measurement Of The Nucleon FN₂/FP₂ Structure Function Ratio By The Jefferson Lab Marathon Tritium/Helium-3 Deep Inelastic Scattering Experiment, D. Abrams, H. Albataineh, B. S. Aljawrneh, S. Alsalmi, D. Androic, K. Aniol, W. Armstrong, J. Arrington, H. Atac, T. Averett, C. Ayerbe Gayoso, X. Bai, J. Bane, J. Barcus, A. Beck, V. Bellini, H. Bhatt, D. Bhetuwal, D. Biswas, D. Blyth, W. Boeglin, D. Bulumulla, Et Al.
Physics Faculty Publications
The ratio of the nucleon F2 structure functions, Fn2/Fp2, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from 3H and 3He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab using two high-resolution spectrometers for electron detection, and a cryogenic target system which included a low-activity tritium cell. The data analysis used a novel technique exploiting the mirror symmetry of the two nuclei, which essentially eliminates many theoretical uncertainties in the extraction of the ratio. The results, which cover the Bjorken …
New Measurements Of The Beam-Normal Single Spin Asymmetry In Elastic Electron Scattering Over A Range Of Spin-0 Nuclei, Prex And Crex Collaborations, D. Adhikari, H. Albataineh, D. Androic, F. Hauenstein, M.N.H. Rashad, W. Zhang, J. Zhang, X. Zheng, Et Al.
New Measurements Of The Beam-Normal Single Spin Asymmetry In Elastic Electron Scattering Over A Range Of Spin-0 Nuclei, Prex And Crex Collaborations, D. Adhikari, H. Albataineh, D. Androic, F. Hauenstein, M.N.H. Rashad, W. Zhang, J. Zhang, X. Zheng, Et Al.
Physics Faculty Publications
We report precision determinations of the beam-normal single spin asymmetries (An) in the elastic scattering of 0.95 and 2.18 GeV electrons off 12C, 40Ca, 48Ca, and 208Pb at very forward angles where the most detailed theoretical calculations have been performed. The first measurements of An for 40Ca and 48Ca are found to be similar to that of 12C, consistent with expectations and thus demonstrating the validity of theoretical calculations for nuclei with Z ≤ 20. We also report An for 208Pb at two …
Reply To "Comment On 'Quasielastic Lepton Scattering And B=Back-To-Back Nucleons In The Short-Time Approximation' ", S. Pastore, J. Carlson, Rocco Schiavilla, J. L. Barrow, S. Gandolfi, R. B. Wiringa
Reply To "Comment On 'Quasielastic Lepton Scattering And B=Back-To-Back Nucleons In The Short-Time Approximation' ", S. Pastore, J. Carlson, Rocco Schiavilla, J. L. Barrow, S. Gandolfi, R. B. Wiringa
Physics Faculty Publications
We briefly review the concept of scaling and how it occurs in quasielastic electron and neutrino scattering from nuclei, and then the particular approach to scaling in the short-time approximation. We show that, whereas two-nucleon currents do significantly enhance the transverse electromagnetic response, they do not spoil scaling, but, in fact, enhance it. We provide scaling results obtained in the short-time approximation that verify this claim. The enhanced scaling, although obtained empirically, is not “accidental”—as claimed in [O. Benhar, Phys. Rev. C 105, 049801 (2022)]—but rather reflects quasielastic kinematics and the dominant role played by pion-exchange interactions and currents …
Inclusive Electron Scattering And The Genie Neutrino Event Generator, A. Papadopoulou, A. Ashkenazi, S. Gardiner, M. Betancourt, S. Dytman, L. B. Weinstein, E. Piasetzky, F. Hauenstein, M. Khachatryan, S. Dolan, G. D. Megias, O. Hen
Inclusive Electron Scattering And The Genie Neutrino Event Generator, A. Papadopoulou, A. Ashkenazi, S. Gardiner, M. Betancourt, S. Dytman, L. B. Weinstein, E. Piasetzky, F. Hauenstein, M. Khachatryan, S. Dolan, G. D. Megias, O. Hen
Physics Faculty Publications
The extraction of neutrino mixing parameters from accelerator-based neutrino-oscillation experiments relies on proper modeling of neutrino-nucleus scattering processes using neutrino interaction event generators. Experimental tests of these generators are difficult due to the broad range of neutrino energies produced in accelerator-based beams and the low statistics of current experiments. Here we overcome these difficulties by exploiting the similarity of neutrino and electron interactions with nuclei to test neutrino event generators using high-precision inclusive electron-scattering data. To this end, we revised the electron-scattering mode of the genie event generator (e-GENIE) to include electron-nucleus bremsstrahlung radiation effects and to use, …
Measurement Of The Ar(E, E' P) And Ti(E, E' P) Cross Sections In Jefferson Lab Hall A, L. Gu, D. Abrams, A.M. Ankowski, L. Jiang, B. Aljawrneh, S. Alsalmi, F. Hauenstein, C. Hyde, Et Al., The Jefferson Lab Hall A. Collaboration
Measurement Of The Ar(E, E' P) And Ti(E, E' P) Cross Sections In Jefferson Lab Hall A, L. Gu, D. Abrams, A.M. Ankowski, L. Jiang, B. Aljawrneh, S. Alsalmi, F. Hauenstein, C. Hyde, Et Al., The Jefferson Lab Hall A. Collaboration
Physics Faculty Publications
The E12-14-012 experiment, performed in Jefferson Lab Hall A, has collected exclusive electron-scattering data (e, e'p) in parallel kinematics using natural argon and natural titanium targets. Here we report the first results of the analysis of the data set corresponding to beam energy 2222 GeV, electron scattering angle 21.5 degrees, and proton emission angle -50°. The differential cross sections, measured with ≈ 4% uncertainty, have been studied as a function of missing energy and missing momentum, and compared to the results of Monte Carlo simulations, obtained from a model based on the distorted-wave impulse approximation.
Probing The Deuteron At Very Large Internal Momenta, C. Yero, D. Abrams, Z Ahmed, F. Hauenstein, S.A. Wood, J. Zhang, Et Al., Hall C. Collaboration
Probing The Deuteron At Very Large Internal Momenta, C. Yero, D. Abrams, Z Ahmed, F. Hauenstein, S.A. Wood, J. Zhang, Et Al., Hall C. Collaboration
Physics Faculty Publications
We measure 2H(e,e′p)n cross sections at 4-momentum transfers of Q2 = 4.5 ± 0.5 (GeV/c)2 over a range of neutron recoil momenta pr, reaching up to ∼1.0 GeV/c. We obtain data at fixed neutron recoil angles θnq = 35°, 45°, and 75° with respect to the 3-momentum transfer →q. The new data agree well with previous data, which reached pr ∼ 500 MeV/c. At θnq = 35° and 45°, final state interactions, meson exchange currents, and isobar currents are suppressed and the plane wave impulse approximation provides the dominant cross section contribution. …
First Measurement Of Direct Photoproduction Of The A2(1320)⁰ Meson On The Proton, K.P. Adhikari, M. J. Amaryan, D. Bullumulla, F. Hauenstein, M. Khachatryan, Y. Prok, Et Al., Clas Collaboration
First Measurement Of Direct Photoproduction Of The A2(1320)⁰ Meson On The Proton, K.P. Adhikari, M. J. Amaryan, D. Bullumulla, F. Hauenstein, M. Khachatryan, Y. Prok, Et Al., Clas Collaboration
Physics Faculty Publications
We present the first measurement of the reaction 𝛾p -> a₂(1320)⁰ p in the photon energy range 3.5-5.5 GeV and four-momentum transfer squared 0.2 < -t < 2.0 GeV2. Data were collected with the CEBAF Large Acceptance Spectrometer detector at the Thomas Jefferson National Accelerator Facility. The a2resonance was detected by measuring the reaction 𝛾p → π0ηp and reconstructing the π0η invariant mass. The most prominent feature of the differential cross section is a dip at -t ≈ 0.55 GeV2. This can be described in the framework of Regge phenomenology, where the exchange degeneracy hypothesis …
First Measurement Of The Ar (E,E')X Cross Section At Jefferson Laboratory, H. Dai, M. Murphy, V. Pandey, D. Abrams, D. Nguyen, B. Aljawrneh, F. Hauenstein, D. W. Higinbotham, Charles Hyde, The Jefferson Lab Hall A Collaboration
First Measurement Of The Ar (E,E')X Cross Section At Jefferson Laboratory, H. Dai, M. Murphy, V. Pandey, D. Abrams, D. Nguyen, B. Aljawrneh, F. Hauenstein, D. W. Higinbotham, Charles Hyde, The Jefferson Lab Hall A Collaboration
Physics Faculty Publications
The success of the ambitious programs of both long- and short-baseline neutrino-oscillation experiments employing liquid-argon time-projection chambers will greatly rely on the precision with which the weak response of the argon nucleus can be estimated. In the E12-14-012 experiment at Jefferson Lab Hall A, we studied the properties of the argon nucleus by scattering a high-quality electron beam off a high-pressure gaseous argon target. Here, we present the measured 40Ar(e,e') double differential cross section at incident electron energy E=2.222 GeV and scattering angle Θ = 15.54°. The data cover a broad range of energy transfers, where quasielastic scattering and …
Measurement Of The Q² Dependence Of The Deuteron Spin Structure Function G1 And Its Moments At Low Q² With Clas, Clas Collaboration, K. P. Adhikari, L. El Fassi, S E. Kuhn, M. J. Amaryan, S. Bültmann, G. Charles, Gail Dodge, N. Guler, C. E. Hyde, A. Klein, D. Payette, J. Poudel, Y. Prok, L. B. Weinstein, J. Zhang, Z. W. Zhao
Measurement Of The Q² Dependence Of The Deuteron Spin Structure Function G1 And Its Moments At Low Q² With Clas, Clas Collaboration, K. P. Adhikari, L. El Fassi, S E. Kuhn, M. J. Amaryan, S. Bültmann, G. Charles, Gail Dodge, N. Guler, C. E. Hyde, A. Klein, D. Payette, J. Poudel, Y. Prok, L. B. Weinstein, J. Zhang, Z. W. Zhao
Physics Faculty Publications
We measured the g1 spin structure function of the deuteron at low Q2, where QCD can be approximated with chiral perturbation theory (χPT). The data cover the resonance region, up to an invariant mass of W ≈ 1.9 GeV. The generalized Gerasimov-Drell-Hearn sum, the moment Γd1 and the spin polarizability γd0 are precisely determined down to a minimum Q2 of 0.02 GeV2 for the first time, about 2.5 times lower than that of previous data. We compare them to several χPT calculations and models. These results are the first in a …
Determination Of The Proton Spin Structure Functions For 0.05 < Q2 <5gev2 Using Clas, R. G. Fersch, N. Guler, P. Bosted, A. Deur, K. Griffioen, C. Keith, S E. Kuhn, R. Minehart, Y. Prok, K. P. Adhikari, S. Bültmann, S. Careccia, Gail Dodge, V. G. Lagerquist, L. B. Weinstein
Determination Of The Proton Spin Structure Functions For 0.05 < Q2 <5gev2 Using Clas, R. G. Fersch, N. Guler, P. Bosted, A. Deur, K. Griffioen, C. Keith, S E. Kuhn, R. Minehart, Y. Prok, K. P. Adhikari, S. Bültmann, S. Careccia, Gail Dodge, V. G. Lagerquist, L. B. Weinstein
Physics Faculty Publications
We present the results of our final analysis of the full data set of gp1 Q2, the spin structure function of the proton, collected using CLAS at Jefferson Laboratory in 2000-2001. Polarized electrons with energies of 1.6, 2.5, 4.2, and 5.7 GeV were scattered from proton targets 15NH3 dynamically polarized along the beam direction) and detected with CLAS. From the measured double spin asymmetries, we extracted virtual photon asymmetries Ap1 and Ap2 and spin structure functions g p1 and gp2 over a wide kinematic range (0.05 GeV …