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Full-Text Articles in Quantum Physics
Cross Sections And Beam Asymmetries For E ⃗ P → Enπ+ In The Nucleon Resonance Region For 1.7 ⩽ Q2 ⩽ 4.5 Gev2, M. J. Amaryan, H. Bagdasaryan, S. Bültmann, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, A. V. Klimenko, S. E. Kuhn, J. Lachniet, R. A. Niyazov, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., The Clas Collaboration
Cross Sections And Beam Asymmetries For E ⃗ P → Enπ+ In The Nucleon Resonance Region For 1.7 ⩽ Q2 ⩽ 4.5 Gev2, M. J. Amaryan, H. Bagdasaryan, S. Bültmann, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, N. Guler, C. E. Hyde-Wright, N. Kalantarians, A. Klein, A. V. Klimenko, S. E. Kuhn, J. Lachniet, R. A. Niyazov, F. Sabatié, S. Tkachenko, L. B. Weinstein, J. Zhang, Et Al., The Clas Collaboration
Physics Faculty Publications
The exclusive electroproduction process e ⃗ p → e'nπ+ was measured in the range of the photon virtuality Q2 =1.7-4.5 GeV2, and the invariant mass range for the n π+ system of W=1.15-1.7 GeV using the CEBAF Large Acceptance Spectrometer. For the first time, these kinematics are probed in exclusive π+ production from protons with nearly full coverage in the azimuthal and polar angles of the nπ+ center-of-mass system. The nπ+ channel has particular sensitivity to the isospin 1/2 excited nucleon states, and together with the pπ0 final state will serve …
Electroexcitation Of The Roper Resonance For 1.7 < Q² < 4.5gev² In Ep → Enπ+, Clas Collaboration, M. J. Amaryan, M. Bektasoglu, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, G. Gavalian, N. Guler, C. E. Hyde, A. Klein, S. E. Kuhn, L. M. Qin, L. B. Weinstein, J. Yun, J. Zhang
Electroexcitation Of The Roper Resonance For 1.7 < Q² < 4.5gev² In Ep → Enπ+, Clas Collaboration, M. J. Amaryan, M. Bektasoglu, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, T. A. Forest, G. Gavalian, N. Guler, C. E. Hyde, A. Klein, S. E. Kuhn, L. M. Qin, L. B. Weinstein, J. Yun, J. Zhang
Physics Faculty Publications
The helicity amplitudes of the electroexcitation of the Roper resonance are extracted for 1.7 < Q2 < 4.5 GeV2 from recent high precision JLab-CLAS cross section and longitudinally polarized beam asymmetry data for π+ electroproduction on protons at W=1.15-1.69 GeV. The analysis is made using two approaches, dispersion relations and a unitary isobar model, which give consistent Q2 behavior of the helicity amplitudes for the gamma*p -> N (1440)P11 transition. It is found that the transverse helicity amplitude A 1/2, which is large and negative at Q2=0, becomes large and positive at Q2 similar or equal …
Electroproduction Of ɸ(1020) Mesons At 1.4 ≤ Q² ≤ 3.8 Gev² Measured With The Clas Spectrometer, Clas Collaboration, M. J. Amaryan, H. Bagdasaryan, M. Bektasoglu, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, C. E. Hyde-Wright, H. G. Jungst, N. Kalantarians, A. Klien, A. V. Klimenko, S. E. Kuhn, R. A. Niyazov, T. Tkachenko, L. B. Weinstein, J. Zhang
Electroproduction Of ɸ(1020) Mesons At 1.4 ≤ Q² ≤ 3.8 Gev² Measured With The Clas Spectrometer, Clas Collaboration, M. J. Amaryan, H. Bagdasaryan, M. Bektasoglu, S. Bültmann, S. L. Careccia, K. V. Dharmawardane, G. E. Dodge, G. Gavalian, C. E. Hyde-Wright, H. G. Jungst, N. Kalantarians, A. Klien, A. V. Klimenko, S. E. Kuhn, R. A. Niyazov, T. Tkachenko, L. B. Weinstein, J. Zhang
Physics Faculty Publications
Electroproduction of exclusive ϕ vector mesons has been studied with the CLAS detector in the kinematic range 1.4 ⩽ Q2 ⩽ 3.8 GeV2 ,0.0 ⩽ t′ ⩽3.6 GeV2 , and 2.0 ⩽ W ⩽ 3.0 GeV. The scaling exponent for the total cross section as 1/(Q2 +M2ϕ)n was determined to be n = 2.49 ± 0.33. The slope of the four-momentum transfer t′ distribution is bϕ = 0.98 ± 0.17 GeV-2 . Under the assumption of s -channel helicity conservation, we determine the ratio of longitudinal to transverse cross sections …