Physical Sciences and Mathematics | Open Access Articles

Exclusive Η Electroproduction At W > 2 Gev With Clas And Transversity Generalized Parton Distributions, I. Bedlinskiy, V. Kubarovsky, P. Stoler, K. P. Adhikari, Z. Akbar, S. Anefalos Pereira, H. Avakian, J. Ball, N. A. Baltzell, M. Battaglieri, C. E. Hyde, M. Khachatryan, S E. Kuhn, Y. Prok, B. Torayev, L. B. Weinstein

Physics Faculty Publications

The cross section of the exclusive η electroproduction reaction ep -> e'p' η was measured at Jefferson Laboratory with a 5.75 GeV electron beam and the CLAS detector. Differential cross sections d⁴σ /dtdQ² dx_Bd φ_η and structure functions σ_U=σ_T + εσ_L, σ_TT, and σ_LT, as functions of t, were obtained over a wide range of Q² and x_B. The η structure functions are compared with those previously measured for π⁰ at the same kinematics. At low t, both π …

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The Heavy Photon Search Beamline And Its Performance, N. Baltzell, H. Egiyan, M. Ehrhart, C. Field, A. Freyberger, F.-X. Girod, M. Holtrop, J. Jaros, G. Kalicy, T. Maruyama, H. Vance

Physics Faculty Publications

The Heavy Photon Search (HPS) is an experiment to search for a hidden sector photon, aka a heavy photon or dark photon, in fixed target electroproduction at the Thomas Jefferson National Accelerator Facility (JLab). The HPS experiment searches for the e⁺e^-decay of the heavy photon with bump hunt and detached vertex strategies using a compact, large acceptance forward spectrometer, consisting of a silicon microstrip detector (SVT) for tracking and vertexing, and a PbWO₄electromagnetic calorimeter for energy measurement and fast triggering. To achieve large acceptance and good vertexing resolution, the first layer of silicon detectors …

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Hom And Impedance Study Of Rf Separators For Lcls-Ii, S. U. De Silva, B.R.P. Gamage, R. G. Olave, J. R. Delayen, G. A. Krafft, T. Satogata

Physics Faculty Publications

The LCLS-II upgrade requires an rf spreader system to guide bunches into a switchyard delivering beam to two undulators and the primary beam dump. The beam pattern therefore needs a 3-way beam spreader. An rf deflecting cavity concept was proposed that includes both superconducting and normal conducting options. We characterize the higher order modes (HOM) of these rf separator cavities and evaluate beam dynamics effects due to potential HOM excitation. This study includes both short term wake and multi-bunch effects.

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Measurement Of The Generalized Form Factors Near Threshold Via ˠ*P→Nπ+ At High Q², Clas Collaboration, K. Park, R. W. Gothe, K. P. Adhikari, D. Adikaram, R. P. Bennett, C. E. Hyde, A. Klein, S. E. Kuhn, H. Seraydaryan

Physics Faculty Publications

We report on the first measurement of the F₂ structure function of the neutron from the semi-inclusive scattering of electrons from deuterium, with low-momentum protons detected in the backward hemisphere. Restricting the momentum of the spectator protons to ≲ 100 MeV/c and their angles to ≳ 100° relative to the momentum transfer allows an interpretation of the process in terms of scattering from nearly on-shell neutrons. The Fⁿ₂ data collected cover the nucleon-resonance and deep-inelastic regions over a wide range of Bjorken x for 0.65 < Q² 2, with uncertainties from nuclear corrections estimated to be less …

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Evidence For The Onset Of Color Transparency In Ρ0 Electroproduction Off Nuclei, L. El Fassi, L. Zana, H. Hafidi, M. Holtrop, B. Mustapha, W. K. Brooks, H. Hakobyan, Z. Zheng, K. P. Adhikari, D. Adikaram, M. J. Amaryan, H. Baghdasaryan, S. Bültmann, G. E. Dodge, C. E. Hyde, A. Klein, S. E. Kuhn, M. Mayer, H. Seraydaryan, L. B. Weinstein

Physics Faculty Publications

We have measured the nuclear transparency of the incoherent diffractive A( e , e ′ ρ⁰ ) process in ¹²C and ⁵⁶Fe targets relative to ²H using a 5 GeV electron beam. The nuclear transparency, the ratio of the produced ρ⁰ ʼs on a nucleus relative to deuterium, which is sensitive to ρA interaction, was studied as function of the coherence length (lc), a lifetime of the hadronic fluctuation of the virtual photon, and the four-momentum transfer squared (Q²). While the transparency for both ¹²C and ⁵⁶Fe …

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Crab Crossing Consideration For Meic, S. Ahmed, Y. Derbenev, Geoffrey A. Krafft, Y. Zhang, Subashini De Silva, Jean R. Delayen, A. Castilla

Physics Faculty Publications

Crab crossing of colliding electron and ion beams is essential for accommodating the high bunch repetition frequency in the conceptual design of MEIC – a high luminosity polarized electron-ion collider at Jefferson Lab. The scheme eliminates parasitic beam-beam interactions and avoids luminosity reduction by restoring head-on collisions at interaction points. In this paper, we report the possible crabbing schemes and requirements for both electron and proton beams.

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Physics Faculty Publications

The Heavy Photon Search Beamline And Its Performance, N. Baltzell, H. Egiyan, M. Ehrhart, C. Field, A. Freyberger, F.-X. Girod, M. Holtrop, J. Jaros, G. Kalicy, T. Maruyama, H. Vance

Physics Faculty Publications

Hom And Impedance Study Of Rf Separators For Lcls-Ii, S. U. De Silva, B.R.P. Gamage, R. G. Olave, J. R. Delayen, G. A. Krafft, T. Satogata

Physics Faculty Publications

Measurement Of The Generalized Form Factors Near Threshold Via ˠ*P→Nπ+ At High Q², Clas Collaboration, K. Park, R. W. Gothe, K. P. Adhikari, D. Adikaram, R. P. Bennett, C. E. Hyde, A. Klein, S. E. Kuhn, H. Seraydaryan

Physics Faculty Publications

Physics Faculty Publications

Crab Crossing Consideration For Meic, S. Ahmed, Y. Derbenev, Geoffrey A. Krafft, Y. Zhang, Subashini De Silva, Jean R. Delayen, A. Castilla

Physics Faculty Publications