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Full-Text Articles in Physics
¹² C(E,E'Pn) Measurements Of Short Range Correlations In The Tensor-To-Scalar Interaction Transition Region, I. Korover, J. R. Pybus, A. Schmidt, F. Hauenstein, M. Duer, L. B. Weinstein, M. J. Amaryan, D. Bullumulla, M. Hattawy, X. Zheng, Et Al., The Clas Collaboration
¹² C(E,E'Pn) Measurements Of Short Range Correlations In The Tensor-To-Scalar Interaction Transition Region, I. Korover, J. R. Pybus, A. Schmidt, F. Hauenstein, M. Duer, L. B. Weinstein, M. J. Amaryan, D. Bullumulla, M. Hattawy, X. Zheng, Et Al., The Clas Collaboration
Physics Faculty Publications
High-momentum configurations of nucleon pairs at short-distance are probed using measurements of the 12C(e,'p) and 12C (e,e'pN) reactions (where N is either n or p), at high Q2 and 𝒙B > 1.1. The data span a missing-momentum range of 300-1000 MeV/c and are predominantly sensitive to the transition region of the strong nuclear interaction from a tensor to scalar interaction. The data are well reproduced by theoretical calculations using the generalized contact formalism with both chiral and phenomenological nucleon-nucleon (NN) interaction models. This agreement suggests that the measured high missing-momentum protons up to 1000 MeV/c predominantly …
First Measurement Of The Helicity Asymmetry E In Ƞ Photoproduction On The Proton, I. Senderovich, B.T. Morrison, M. Dugger, B.G. Ritchie, E. Pasyuk, R. Tucker, J. Brock, C. Carlin, C.D. Keith, D. G. Meekins, Y. Prok
First Measurement Of The Helicity Asymmetry E In Ƞ Photoproduction On The Proton, I. Senderovich, B.T. Morrison, M. Dugger, B.G. Ritchie, E. Pasyuk, R. Tucker, J. Brock, C. Carlin, C.D. Keith, D. G. Meekins, Y. Prok
Physics Faculty Publications
Results are presented for the first measurement of the double-polarization helicity asymmetry E for the ƞ photoproduction reaction ɣp -> ηp. Data were obtained using the FROzen Spin Target (FROST) with the CLAS spectrometer in Hall B at Jefferson Lab, covering a range of center-of-mass energy W from threshold to 2.15 GeV and a large range in center-of-mass polar angle. As an initial application of these data, the results have been incorporated into the Jülich-Bonn model to examine the case for the existence of a narrow N* resonance between 1.66 and 1.70 GeV. The addition of these data to the …
Dielectron Azimuthal Anisotrophy At Mid-Rapidity In Au+Au Collisions At √ˢᶰᶰ = 200 Gev, L. Adamczyk, J. K. Adkins, G. Agakishiev, S. Bültmann, I Koralt, Star Collaboration
Dielectron Azimuthal Anisotrophy At Mid-Rapidity In Au+Au Collisions At √ˢᶰᶰ = 200 Gev, L. Adamczyk, J. K. Adkins, G. Agakishiev, S. Bültmann, I Koralt, Star Collaboration
Physics Faculty Publications
We report on the first measurement of the azimuthal anisotropy v2 of dielectrons (e+e- pairs) at mid-rapidity from √ˢᶰᶰ = 200 GeV Au + Au collisions with the STAR detector at the Relativistic Heavy Ion Collider (RHIC), presented as a function of transverse momentum pT for different invariant-mass regions. In the mass region Mee < 1.1 GeV/c2 the dielectron v2measurements are found to be consistent with expectations from π0, η, ω, and Φ decay contributions. In the mass region 1.1 < Mee < 2.9 GeV/c2, the measured dielectron v2is consistent, within experimental …
Exclusive Πᵒ Electroproduction At W > 2 Gev With Clas, I. Bedlinskiy, K. P. Adhikari, L. El Fassi, A. Klein, S. E. Kuhn, Clas Collaboration
Exclusive Πᵒ Electroproduction At W > 2 Gev With Clas, I. Bedlinskiy, K. P. Adhikari, L. El Fassi, A. Klein, S. E. Kuhn, Clas Collaboration
Physics Faculty Publications
Exclusive neutral-pion electroproduction (ep → e'p'π0 was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections d4σ/dtdQ2dxBdΦπ and structure functions σT+ ϵσL, σTT, and σLT as functions of t were obtained over a wide range of Q2 and xB. The data are compared with Regge and handbag theoretical calculations. Analyses in both frameworks find that a large dominance of transverse processes is necessary to explain the experimental results. For the Regge analysis it is found …
J/Ψ Production At Low Pᵀ In Au + Au And Cu + Cu Collisions At √ˢᴺᴺ = 200 Gev With The Star Detector, L. Adamczyk, J. K. Adkins, G. Agakishiev, S. Bültmann, I. Koralt, Star Collaboration
J/Ψ Production At Low Pᵀ In Au + Au And Cu + Cu Collisions At √ˢᴺᴺ = 200 Gev With The Star Detector, L. Adamczyk, J. K. Adkins, G. Agakishiev, S. Bültmann, I. Koralt, Star Collaboration
Physics Faculty Publications
The J/ψ pT spectrum and nuclear modification factor (RAA) are reported for pT < 5 GeV/c and |y| < 1 from 0% to 60% central Au + Au and Cu + Cu collisions at √ˢᴺᴺ = 200 GeV at STAR. A significant suppression of pT - integrated J/ψ production is observed in central Au + Au events. The Cu + Cu data are consistent with no suppression, although the precision is limited by the available statistics. RAA in Au + Au collisions exhibits a strong suppression at low transverse momentum and gradually increases with pT. The data are compared to high-pT STAR results and previously published BNL Relativistic Heavy Ion Collider results. Comparing with model calculations, it is found that the invariant yields …
Beam Asymmetry Σ For Π+ And Π0 Photoproduction On The Proton For Photon Energies From 1.102 To 1.862 Gev, K. P. Adhikari, D. Adikaram, M. J. Amaryan, C. S. Nepali, Y. Prok, Clas Collaboration
Beam Asymmetry Σ For Π+ And Π0 Photoproduction On The Proton For Photon Energies From 1.102 To 1.862 Gev, K. P. Adhikari, D. Adikaram, M. J. Amaryan, C. S. Nepali, Y. Prok, Clas Collaboration
Physics Faculty Publications
Beam asymmetries for the reactions ˠp -> pπ0 and ˠp -> nπ+have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged, linearly polarized photon beam with energies from 1.102-1.862 GeV. A Fourier moment technique for extracting beam asymmetries from experimental data is described. The results reported here possess greater precision and finer energy resolution than previous measurements. Our data for both pion reactions appear to favor the SAID and Bonn-Gatchina scattering analyses over the older Mainz MAID predictions. After incorporating the present set of beam asymmetries into the world database, exploratory fits made with …
Cross Sections For The Ɣp → K*+Ʌ And Ɣp → K*+Σº Reactions Measured At Clas, K.P. Adhikari, M. J. Amaryan, C. E. Hyde, S. Koirala, M. Mayer, Clas Collaboration
Cross Sections For The Ɣp → K*+Ʌ And Ɣp → K*+Σº Reactions Measured At Clas, K.P. Adhikari, M. J. Amaryan, C. E. Hyde, S. Koirala, M. Mayer, Clas Collaboration
Physics Faculty Publications
The first high-statistics cross sections for the reactions ɣp → K*+Ʌ and ɣp → K*+Σº were measured using the CLAS detector at photon energies between threshold and 3.9 GeV at the Thomas Jefferson National Accelerator Facility. Differential cross sections are presented over the full range of the center-of-mass angles, and then fitted to Legendre polynomials to extract the total cross section. Results for the K*+Ʌ final state are compared with two different calculations in an isobar and a Regge model, respectively. Theoretical calculations significantly underestimate the K*+Ʌ total cross sections between 2.1 and 2.6 GeV, but are in better agreement …