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A Measurement of the Interference Structure Function, R_LT, for the 12C(e,e'p) reaction in the Quasielastic Region

M. Holtrop·D. Jordan·T. McIlvain·R. Alarcon·R. Beck·W. Bertozzi·V. Bhushan·W. Boeglin·J. P. Chen·D. Dale·G. Dodson·S. Dolfini·K. Dow·J. Dzengeleski·M. B. Epstein·M. Farkhondeh·S. Gilad·J. Gorgen·K. Joo·J. Kelsey·W. Kim·R. Laszewski·R. Lourie·J. Mandeville·D. Margaziotis·D. Martinez·R. Miskimen·C. Papanicolas·S. Penn·W. Sapp·A. J. Sarty·D. Tieger·C. Tschalaer·W. Turchinetz·G. Warren·L. Weinstein·S. Williamson
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Abstract

The coincidence cross-section and the interference structure function, R_LT, were measured for the 12C(e,e'p) 11B reaction at quasielastic kinematics and central momentum transfer of q=400 MeV/c. The measurement was at an opening angle of theta_pq=11 degrees, covering a range in missing energy of E_m = 0 to 65 MeV. The R_LT structure function is found to be consistent with zero for E_m > 50 MeV, confirming an earlier study which indicated that R_L vanishes in this region. The integrated strengths of the p- and s-shell are compared with a Distorted Wave Impulse Approximation calculation. The s-shell strength and shape are compared with a Hartree Fock-Random Phase Approximation calculation. The DWIA calculation overestimates the cross sections for p- and s-shell proton knockout as expected, but surprisingly agrees with the extracted R_LT value for both shells. The HF-RPA calculation describes the data more consistently, which may be due to the inclusion of 2-body currents in this calculation.

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M. Holtrop, D. Jordan, T. McIlvain, R. Alarcon, R. Beck, W. Bertozzi, V. Bhushan, W. Boeglin, J. P. Chen, D. Dale, G. Dodson, S. Dolfini, K. Dow, J. Dzengeleski, M. B. Epstein, M. Farkhondeh, S. Gilad, J. Gorgen, K. Joo, J. Kelsey, W. Kim, R. Laszewski, R. Lourie, J. Mandeville, D. Margaziotis, D. Martinez, R. Miskimen, C. Papanicolas, S. Penn, W. Sapp, A. J. Sarty, D. Tieger, C. Tschalaer, W. Turchinetz, G. Warren, L. Weinstein, S. Williamson. 1998-03-25. A Measurement of the Interference Structure Function, R_LT, for the 12C(e,e'p) reaction in the Quasielastic Region. https://doi.org/10.1103/physrevc.58.3205

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